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1// SPDX-License-Identifier: GPL-2.0
2
3#include <linux/bitmap.h>
4#include <linux/kernel.h>
5#include <linux/module.h>
6#include <linux/interrupt.h>
7#include <linux/irq.h>
8#include <linux/spinlock.h>
9#include <linux/list.h>
10#include <linux/device.h>
11#include <linux/err.h>
12#include <linux/debugfs.h>
13#include <linux/seq_file.h>
14#include <linux/gpio.h>
15#include <linux/idr.h>
16#include <linux/slab.h>
17#include <linux/acpi.h>
18#include <linux/gpio/driver.h>
19#include <linux/gpio/machine.h>
20#include <linux/pinctrl/consumer.h>
21#include <linux/fs.h>
22#include <linux/compat.h>
23#include <linux/file.h>
24#include <uapi/linux/gpio.h>
25
26#include "gpiolib.h"
27#include "gpiolib-of.h"
28#include "gpiolib-acpi.h"
29#include "gpiolib-swnode.h"
30#include "gpiolib-cdev.h"
31#include "gpiolib-sysfs.h"
32
33#define CREATE_TRACE_POINTS
34#include <trace/events/gpio.h>
35
36/* Implementation infrastructure for GPIO interfaces.
37 *
38 * The GPIO programming interface allows for inlining speed-critical
39 * get/set operations for common cases, so that access to SOC-integrated
40 * GPIOs can sometimes cost only an instruction or two per bit.
41 */
42
43
44/* When debugging, extend minimal trust to callers and platform code.
45 * Also emit diagnostic messages that may help initial bringup, when
46 * board setup or driver bugs are most common.
47 *
48 * Otherwise, minimize overhead in what may be bitbanging codepaths.
49 */
50#ifdef DEBUG
51#define extra_checks 1
52#else
53#define extra_checks 0
54#endif
55
56/* Device and char device-related information */
57static DEFINE_IDA(gpio_ida);
58static dev_t gpio_devt;
59#define GPIO_DEV_MAX 256 /* 256 GPIO chip devices supported */
60static int gpio_bus_match(struct device *dev, struct device_driver *drv);
61static struct bus_type gpio_bus_type = {
62 .name = "gpio",
63 .match = gpio_bus_match,
64};
65
66/*
67 * Number of GPIOs to use for the fast path in set array
68 */
69#define FASTPATH_NGPIO CONFIG_GPIOLIB_FASTPATH_LIMIT
70
71/* gpio_lock prevents conflicts during gpio_desc[] table updates.
72 * While any GPIO is requested, its gpio_chip is not removable;
73 * each GPIO's "requested" flag serves as a lock and refcount.
74 */
75DEFINE_SPINLOCK(gpio_lock);
76
77static DEFINE_MUTEX(gpio_lookup_lock);
78static LIST_HEAD(gpio_lookup_list);
79LIST_HEAD(gpio_devices);
80
81static DEFINE_MUTEX(gpio_machine_hogs_mutex);
82static LIST_HEAD(gpio_machine_hogs);
83
84static void gpiochip_free_hogs(struct gpio_chip *gc);
85static int gpiochip_add_irqchip(struct gpio_chip *gc,
86 struct lock_class_key *lock_key,
87 struct lock_class_key *request_key);
88static void gpiochip_irqchip_remove(struct gpio_chip *gc);
89static int gpiochip_irqchip_init_hw(struct gpio_chip *gc);
90static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gc);
91static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gc);
92
93static bool gpiolib_initialized;
94
95static inline void desc_set_label(struct gpio_desc *d, const char *label)
96{
97 d->label = label;
98}
99
100/**
101 * gpio_to_desc - Convert a GPIO number to its descriptor
102 * @gpio: global GPIO number
103 *
104 * Returns:
105 * The GPIO descriptor associated with the given GPIO, or %NULL if no GPIO
106 * with the given number exists in the system.
107 */
108struct gpio_desc *gpio_to_desc(unsigned gpio)
109{
110 struct gpio_device *gdev;
111 unsigned long flags;
112
113 spin_lock_irqsave(&gpio_lock, flags);
114
115 list_for_each_entry(gdev, &gpio_devices, list) {
116 if (gdev->base <= gpio &&
117 gdev->base + gdev->ngpio > gpio) {
118 spin_unlock_irqrestore(&gpio_lock, flags);
119 return &gdev->descs[gpio - gdev->base];
120 }
121 }
122
123 spin_unlock_irqrestore(&gpio_lock, flags);
124
125 if (!gpio_is_valid(gpio))
126 pr_warn("invalid GPIO %d\n", gpio);
127
128 return NULL;
129}
130EXPORT_SYMBOL_GPL(gpio_to_desc);
131
132/**
133 * gpiochip_get_desc - get the GPIO descriptor corresponding to the given
134 * hardware number for this chip
135 * @gc: GPIO chip
136 * @hwnum: hardware number of the GPIO for this chip
137 *
138 * Returns:
139 * A pointer to the GPIO descriptor or ``ERR_PTR(-EINVAL)`` if no GPIO exists
140 * in the given chip for the specified hardware number.
141 */
142struct gpio_desc *gpiochip_get_desc(struct gpio_chip *gc,
143 unsigned int hwnum)
144{
145 struct gpio_device *gdev = gc->gpiodev;
146
147 if (hwnum >= gdev->ngpio)
148 return ERR_PTR(-EINVAL);
149
150 return &gdev->descs[hwnum];
151}
152EXPORT_SYMBOL_GPL(gpiochip_get_desc);
153
154/**
155 * desc_to_gpio - convert a GPIO descriptor to the integer namespace
156 * @desc: GPIO descriptor
157 *
158 * This should disappear in the future but is needed since we still
159 * use GPIO numbers for error messages and sysfs nodes.
160 *
161 * Returns:
162 * The global GPIO number for the GPIO specified by its descriptor.
163 */
164int desc_to_gpio(const struct gpio_desc *desc)
165{
166 return desc->gdev->base + (desc - &desc->gdev->descs[0]);
167}
168EXPORT_SYMBOL_GPL(desc_to_gpio);
169
170
171/**
172 * gpiod_to_chip - Return the GPIO chip to which a GPIO descriptor belongs
173 * @desc: descriptor to return the chip of
174 */
175struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc)
176{
177 if (!desc || !desc->gdev)
178 return NULL;
179 return desc->gdev->chip;
180}
181EXPORT_SYMBOL_GPL(gpiod_to_chip);
182
183/* dynamic allocation of GPIOs, e.g. on a hotplugged device */
184static int gpiochip_find_base(int ngpio)
185{
186 struct gpio_device *gdev;
187 int base = GPIO_DYNAMIC_BASE;
188
189 list_for_each_entry(gdev, &gpio_devices, list) {
190 /* found a free space? */
191 if (gdev->base >= base + ngpio)
192 break;
193 /* nope, check the space right after the chip */
194 base = gdev->base + gdev->ngpio;
195 }
196
197 if (gpio_is_valid(base)) {
198 pr_debug("%s: found new base at %d\n", __func__, base);
199 return base;
200 } else {
201 pr_err("%s: cannot find free range\n", __func__);
202 return -ENOSPC;
203 }
204}
205
206/**
207 * gpiod_get_direction - return the current direction of a GPIO
208 * @desc: GPIO to get the direction of
209 *
210 * Returns 0 for output, 1 for input, or an error code in case of error.
211 *
212 * This function may sleep if gpiod_cansleep() is true.
213 */
214int gpiod_get_direction(struct gpio_desc *desc)
215{
216 struct gpio_chip *gc;
217 unsigned int offset;
218 int ret;
219
220 gc = gpiod_to_chip(desc);
221 offset = gpio_chip_hwgpio(desc);
222
223 /*
224 * Open drain emulation using input mode may incorrectly report
225 * input here, fix that up.
226 */
227 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags) &&
228 test_bit(FLAG_IS_OUT, &desc->flags))
229 return 0;
230
231 if (!gc->get_direction)
232 return -ENOTSUPP;
233
234 ret = gc->get_direction(gc, offset);
235 if (ret < 0)
236 return ret;
237
238 /* GPIOF_DIR_IN or other positive, otherwise GPIOF_DIR_OUT */
239 if (ret > 0)
240 ret = 1;
241
242 assign_bit(FLAG_IS_OUT, &desc->flags, !ret);
243
244 return ret;
245}
246EXPORT_SYMBOL_GPL(gpiod_get_direction);
247
248/*
249 * Add a new chip to the global chips list, keeping the list of chips sorted
250 * by range(means [base, base + ngpio - 1]) order.
251 *
252 * Return -EBUSY if the new chip overlaps with some other chip's integer
253 * space.
254 */
255static int gpiodev_add_to_list(struct gpio_device *gdev)
256{
257 struct gpio_device *prev, *next;
258
259 if (list_empty(&gpio_devices)) {
260 /* initial entry in list */
261 list_add_tail(&gdev->list, &gpio_devices);
262 return 0;
263 }
264
265 next = list_first_entry(&gpio_devices, struct gpio_device, list);
266 if (gdev->base + gdev->ngpio <= next->base) {
267 /* add before first entry */
268 list_add(&gdev->list, &gpio_devices);
269 return 0;
270 }
271
272 prev = list_last_entry(&gpio_devices, struct gpio_device, list);
273 if (prev->base + prev->ngpio <= gdev->base) {
274 /* add behind last entry */
275 list_add_tail(&gdev->list, &gpio_devices);
276 return 0;
277 }
278
279 list_for_each_entry_safe(prev, next, &gpio_devices, list) {
280 /* at the end of the list */
281 if (&next->list == &gpio_devices)
282 break;
283
284 /* add between prev and next */
285 if (prev->base + prev->ngpio <= gdev->base
286 && gdev->base + gdev->ngpio <= next->base) {
287 list_add(&gdev->list, &prev->list);
288 return 0;
289 }
290 }
291
292 return -EBUSY;
293}
294
295/*
296 * Convert a GPIO name to its descriptor
297 * Note that there is no guarantee that GPIO names are globally unique!
298 * Hence this function will return, if it exists, a reference to the first GPIO
299 * line found that matches the given name.
300 */
301static struct gpio_desc *gpio_name_to_desc(const char * const name)
302{
303 struct gpio_device *gdev;
304 unsigned long flags;
305
306 if (!name)
307 return NULL;
308
309 spin_lock_irqsave(&gpio_lock, flags);
310
311 list_for_each_entry(gdev, &gpio_devices, list) {
312 struct gpio_desc *desc;
313
314 for_each_gpio_desc(gdev->chip, desc) {
315 if (desc->name && !strcmp(desc->name, name)) {
316 spin_unlock_irqrestore(&gpio_lock, flags);
317 return desc;
318 }
319 }
320 }
321
322 spin_unlock_irqrestore(&gpio_lock, flags);
323
324 return NULL;
325}
326
327/*
328 * Take the names from gc->names and assign them to their GPIO descriptors.
329 * Warn if a name is already used for a GPIO line on a different GPIO chip.
330 *
331 * Note that:
332 * 1. Non-unique names are still accepted,
333 * 2. Name collisions within the same GPIO chip are not reported.
334 */
335static int gpiochip_set_desc_names(struct gpio_chip *gc)
336{
337 struct gpio_device *gdev = gc->gpiodev;
338 int i;
339
340 /* First check all names if they are unique */
341 for (i = 0; i != gc->ngpio; ++i) {
342 struct gpio_desc *gpio;
343
344 gpio = gpio_name_to_desc(gc->names[i]);
345 if (gpio)
346 dev_warn(&gdev->dev,
347 "Detected name collision for GPIO name '%s'\n",
348 gc->names[i]);
349 }
350
351 /* Then add all names to the GPIO descriptors */
352 for (i = 0; i != gc->ngpio; ++i)
353 gdev->descs[i].name = gc->names[i];
354
355 return 0;
356}
357
358/*
359 * devprop_gpiochip_set_names - Set GPIO line names using device properties
360 * @chip: GPIO chip whose lines should be named, if possible
361 *
362 * Looks for device property "gpio-line-names" and if it exists assigns
363 * GPIO line names for the chip. The memory allocated for the assigned
364 * names belong to the underlying firmware node and should not be released
365 * by the caller.
366 */
367static int devprop_gpiochip_set_names(struct gpio_chip *chip)
368{
369 struct gpio_device *gdev = chip->gpiodev;
370 struct device *dev = &gdev->dev;
371 const char **names;
372 int ret, i;
373 int count;
374
375 count = device_property_string_array_count(dev, "gpio-line-names");
376 if (count < 0)
377 return 0;
378
379 /*
380 * When offset is set in the driver side we assume the driver internally
381 * is using more than one gpiochip per the same device. We have to stop
382 * setting friendly names if the specified ones with 'gpio-line-names'
383 * are less than the offset in the device itself. This means all the
384 * lines are not present for every single pin within all the internal
385 * gpiochips.
386 */
387 if (count <= chip->offset) {
388 dev_warn(dev, "gpio-line-names too short (length %d), cannot map names for the gpiochip at offset %u\n",
389 count, chip->offset);
390 return 0;
391 }
392
393 names = kcalloc(count, sizeof(*names), GFP_KERNEL);
394 if (!names)
395 return -ENOMEM;
396
397 ret = device_property_read_string_array(dev, "gpio-line-names",
398 names, count);
399 if (ret < 0) {
400 dev_warn(dev, "failed to read GPIO line names\n");
401 kfree(names);
402 return ret;
403 }
404
405 /*
406 * When more that one gpiochip per device is used, 'count' can
407 * contain at most number gpiochips x chip->ngpio. We have to
408 * correctly distribute all defined lines taking into account
409 * chip->offset as starting point from where we will assign
410 * the names to pins from the 'names' array. Since property
411 * 'gpio-line-names' cannot contains gaps, we have to be sure
412 * we only assign those pins that really exists since chip->ngpio
413 * can be different of the chip->offset.
414 */
415 count = (count > chip->offset) ? count - chip->offset : count;
416 if (count > chip->ngpio)
417 count = chip->ngpio;
418
419 for (i = 0; i < count; i++) {
420 /*
421 * Allow overriding "fixed" names provided by the GPIO
422 * provider. The "fixed" names are more often than not
423 * generic and less informative than the names given in
424 * device properties.
425 */
426 if (names[chip->offset + i] && names[chip->offset + i][0])
427 gdev->descs[i].name = names[chip->offset + i];
428 }
429
430 kfree(names);
431
432 return 0;
433}
434
435static unsigned long *gpiochip_allocate_mask(struct gpio_chip *gc)
436{
437 unsigned long *p;
438
439 p = bitmap_alloc(gc->ngpio, GFP_KERNEL);
440 if (!p)
441 return NULL;
442
443 /* Assume by default all GPIOs are valid */
444 bitmap_fill(p, gc->ngpio);
445
446 return p;
447}
448
449static unsigned int gpiochip_count_reserved_ranges(struct gpio_chip *gc)
450{
451 struct device *dev = &gc->gpiodev->dev;
452 int size;
453
454 /* Format is "start, count, ..." */
455 size = device_property_count_u32(dev, "gpio-reserved-ranges");
456 if (size > 0 && size % 2 == 0)
457 return size;
458
459 return 0;
460}
461
462static int gpiochip_alloc_valid_mask(struct gpio_chip *gc)
463{
464 if (!(gpiochip_count_reserved_ranges(gc) || gc->init_valid_mask))
465 return 0;
466
467 gc->valid_mask = gpiochip_allocate_mask(gc);
468 if (!gc->valid_mask)
469 return -ENOMEM;
470
471 return 0;
472}
473
474static int gpiochip_apply_reserved_ranges(struct gpio_chip *gc)
475{
476 struct device *dev = &gc->gpiodev->dev;
477 unsigned int size;
478 u32 *ranges;
479 int ret;
480
481 size = gpiochip_count_reserved_ranges(gc);
482 if (size == 0)
483 return 0;
484
485 ranges = kmalloc_array(size, sizeof(*ranges), GFP_KERNEL);
486 if (!ranges)
487 return -ENOMEM;
488
489 ret = device_property_read_u32_array(dev, "gpio-reserved-ranges",
490 ranges, size);
491 if (ret) {
492 kfree(ranges);
493 return ret;
494 }
495
496 while (size) {
497 u32 count = ranges[--size];
498 u32 start = ranges[--size];
499
500 if (start >= gc->ngpio || start + count > gc->ngpio)
501 continue;
502
503 bitmap_clear(gc->valid_mask, start, count);
504 }
505
506 kfree(ranges);
507 return 0;
508}
509
510static int gpiochip_init_valid_mask(struct gpio_chip *gc)
511{
512 int ret;
513
514 ret = gpiochip_apply_reserved_ranges(gc);
515 if (ret)
516 return ret;
517
518 if (gc->init_valid_mask)
519 return gc->init_valid_mask(gc,
520 gc->valid_mask,
521 gc->ngpio);
522
523 return 0;
524}
525
526static void gpiochip_free_valid_mask(struct gpio_chip *gc)
527{
528 bitmap_free(gc->valid_mask);
529 gc->valid_mask = NULL;
530}
531
532static int gpiochip_add_pin_ranges(struct gpio_chip *gc)
533{
534 if (gc->add_pin_ranges)
535 return gc->add_pin_ranges(gc);
536
537 return 0;
538}
539
540bool gpiochip_line_is_valid(const struct gpio_chip *gc,
541 unsigned int offset)
542{
543 /* No mask means all valid */
544 if (likely(!gc->valid_mask))
545 return true;
546 return test_bit(offset, gc->valid_mask);
547}
548EXPORT_SYMBOL_GPL(gpiochip_line_is_valid);
549
550static void gpiodevice_release(struct device *dev)
551{
552 struct gpio_device *gdev = to_gpio_device(dev);
553 unsigned long flags;
554
555 spin_lock_irqsave(&gpio_lock, flags);
556 list_del(&gdev->list);
557 spin_unlock_irqrestore(&gpio_lock, flags);
558
559 ida_free(&gpio_ida, gdev->id);
560 kfree_const(gdev->label);
561 kfree(gdev->descs);
562 kfree(gdev);
563}
564
565#ifdef CONFIG_GPIO_CDEV
566#define gcdev_register(gdev, devt) gpiolib_cdev_register((gdev), (devt))
567#define gcdev_unregister(gdev) gpiolib_cdev_unregister((gdev))
568#else
569/*
570 * gpiolib_cdev_register() indirectly calls device_add(), which is still
571 * required even when cdev is not selected.
572 */
573#define gcdev_register(gdev, devt) device_add(&(gdev)->dev)
574#define gcdev_unregister(gdev) device_del(&(gdev)->dev)
575#endif
576
577static int gpiochip_setup_dev(struct gpio_device *gdev)
578{
579 int ret;
580
581 ret = gcdev_register(gdev, gpio_devt);
582 if (ret)
583 return ret;
584
585 /* From this point, the .release() function cleans up gpio_device */
586 gdev->dev.release = gpiodevice_release;
587
588 ret = gpiochip_sysfs_register(gdev);
589 if (ret)
590 goto err_remove_device;
591
592 dev_dbg(&gdev->dev, "registered GPIOs %d to %d on %s\n", gdev->base,
593 gdev->base + gdev->ngpio - 1, gdev->chip->label ? : "generic");
594
595 return 0;
596
597err_remove_device:
598 gcdev_unregister(gdev);
599 return ret;
600}
601
602static void gpiochip_machine_hog(struct gpio_chip *gc, struct gpiod_hog *hog)
603{
604 struct gpio_desc *desc;
605 int rv;
606
607 desc = gpiochip_get_desc(gc, hog->chip_hwnum);
608 if (IS_ERR(desc)) {
609 chip_err(gc, "%s: unable to get GPIO desc: %ld\n", __func__,
610 PTR_ERR(desc));
611 return;
612 }
613
614 if (test_bit(FLAG_IS_HOGGED, &desc->flags))
615 return;
616
617 rv = gpiod_hog(desc, hog->line_name, hog->lflags, hog->dflags);
618 if (rv)
619 gpiod_err(desc, "%s: unable to hog GPIO line (%s:%u): %d\n",
620 __func__, gc->label, hog->chip_hwnum, rv);
621}
622
623static void machine_gpiochip_add(struct gpio_chip *gc)
624{
625 struct gpiod_hog *hog;
626
627 mutex_lock(&gpio_machine_hogs_mutex);
628
629 list_for_each_entry(hog, &gpio_machine_hogs, list) {
630 if (!strcmp(gc->label, hog->chip_label))
631 gpiochip_machine_hog(gc, hog);
632 }
633
634 mutex_unlock(&gpio_machine_hogs_mutex);
635}
636
637static void gpiochip_setup_devs(void)
638{
639 struct gpio_device *gdev;
640 int ret;
641
642 list_for_each_entry(gdev, &gpio_devices, list) {
643 ret = gpiochip_setup_dev(gdev);
644 if (ret)
645 dev_err(&gdev->dev,
646 "Failed to initialize gpio device (%d)\n", ret);
647 }
648}
649
650int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data,
651 struct lock_class_key *lock_key,
652 struct lock_class_key *request_key)
653{
654 struct fwnode_handle *fwnode = NULL;
655 struct gpio_device *gdev;
656 unsigned long flags;
657 unsigned int i;
658 u32 ngpios = 0;
659 int base = 0;
660 int ret = 0;
661
662 if (gc->fwnode)
663 fwnode = gc->fwnode;
664 else if (gc->parent)
665 fwnode = dev_fwnode(gc->parent);
666
667 /*
668 * First: allocate and populate the internal stat container, and
669 * set up the struct device.
670 */
671 gdev = kzalloc(sizeof(*gdev), GFP_KERNEL);
672 if (!gdev)
673 return -ENOMEM;
674 gdev->dev.bus = &gpio_bus_type;
675 gdev->dev.parent = gc->parent;
676 gdev->chip = gc;
677 gc->gpiodev = gdev;
678
679 of_gpio_dev_init(gc, gdev);
680 acpi_gpio_dev_init(gc, gdev);
681
682 /*
683 * Assign fwnode depending on the result of the previous calls,
684 * if none of them succeed, assign it to the parent's one.
685 */
686 gc->fwnode = gdev->dev.fwnode = dev_fwnode(&gdev->dev) ?: fwnode;
687
688 gdev->id = ida_alloc(&gpio_ida, GFP_KERNEL);
689 if (gdev->id < 0) {
690 ret = gdev->id;
691 goto err_free_gdev;
692 }
693
694 ret = dev_set_name(&gdev->dev, GPIOCHIP_NAME "%d", gdev->id);
695 if (ret)
696 goto err_free_ida;
697
698 device_initialize(&gdev->dev);
699 if (gc->parent && gc->parent->driver)
700 gdev->owner = gc->parent->driver->owner;
701 else if (gc->owner)
702 /* TODO: remove chip->owner */
703 gdev->owner = gc->owner;
704 else
705 gdev->owner = THIS_MODULE;
706
707 /*
708 * Try the device properties if the driver didn't supply the number
709 * of GPIO lines.
710 */
711 ngpios = gc->ngpio;
712 if (ngpios == 0) {
713 ret = device_property_read_u32(&gdev->dev, "ngpios", &ngpios);
714 if (ret == -ENODATA)
715 /*
716 * -ENODATA means that there is no property found and
717 * we want to issue the error message to the user.
718 * Besides that, we want to return different error code
719 * to state that supplied value is not valid.
720 */
721 ngpios = 0;
722 else if (ret)
723 goto err_free_dev_name;
724
725 gc->ngpio = ngpios;
726 }
727
728 if (gc->ngpio == 0) {
729 chip_err(gc, "tried to insert a GPIO chip with zero lines\n");
730 ret = -EINVAL;
731 goto err_free_dev_name;
732 }
733
734 if (gc->ngpio > FASTPATH_NGPIO)
735 chip_warn(gc, "line cnt %u is greater than fast path cnt %u\n",
736 gc->ngpio, FASTPATH_NGPIO);
737
738 gdev->descs = kcalloc(gc->ngpio, sizeof(*gdev->descs), GFP_KERNEL);
739 if (!gdev->descs) {
740 ret = -ENOMEM;
741 goto err_free_dev_name;
742 }
743
744 gdev->label = kstrdup_const(gc->label ?: "unknown", GFP_KERNEL);
745 if (!gdev->label) {
746 ret = -ENOMEM;
747 goto err_free_descs;
748 }
749
750 gdev->ngpio = gc->ngpio;
751 gdev->data = data;
752
753 spin_lock_irqsave(&gpio_lock, flags);
754
755 /*
756 * TODO: this allocates a Linux GPIO number base in the global
757 * GPIO numberspace for this chip. In the long run we want to
758 * get *rid* of this numberspace and use only descriptors, but
759 * it may be a pipe dream. It will not happen before we get rid
760 * of the sysfs interface anyways.
761 */
762 base = gc->base;
763 if (base < 0) {
764 base = gpiochip_find_base(gc->ngpio);
765 if (base < 0) {
766 spin_unlock_irqrestore(&gpio_lock, flags);
767 ret = base;
768 base = 0;
769 goto err_free_label;
770 }
771 /*
772 * TODO: it should not be necessary to reflect the assigned
773 * base outside of the GPIO subsystem. Go over drivers and
774 * see if anyone makes use of this, else drop this and assign
775 * a poison instead.
776 */
777 gc->base = base;
778 } else {
779 dev_warn(&gdev->dev,
780 "Static allocation of GPIO base is deprecated, use dynamic allocation.\n");
781 }
782 gdev->base = base;
783
784 ret = gpiodev_add_to_list(gdev);
785 if (ret) {
786 spin_unlock_irqrestore(&gpio_lock, flags);
787 chip_err(gc, "GPIO integer space overlap, cannot add chip\n");
788 goto err_free_label;
789 }
790
791 for (i = 0; i < gc->ngpio; i++)
792 gdev->descs[i].gdev = gdev;
793
794 spin_unlock_irqrestore(&gpio_lock, flags);
795
796 BLOCKING_INIT_NOTIFIER_HEAD(&gdev->notifier);
797 init_rwsem(&gdev->sem);
798
799#ifdef CONFIG_PINCTRL
800 INIT_LIST_HEAD(&gdev->pin_ranges);
801#endif
802
803 if (gc->names) {
804 ret = gpiochip_set_desc_names(gc);
805 if (ret)
806 goto err_remove_from_list;
807 }
808 ret = devprop_gpiochip_set_names(gc);
809 if (ret)
810 goto err_remove_from_list;
811
812 ret = gpiochip_alloc_valid_mask(gc);
813 if (ret)
814 goto err_remove_from_list;
815
816 ret = of_gpiochip_add(gc);
817 if (ret)
818 goto err_free_gpiochip_mask;
819
820 ret = gpiochip_init_valid_mask(gc);
821 if (ret)
822 goto err_remove_of_chip;
823
824 for (i = 0; i < gc->ngpio; i++) {
825 struct gpio_desc *desc = &gdev->descs[i];
826
827 if (gc->get_direction && gpiochip_line_is_valid(gc, i)) {
828 assign_bit(FLAG_IS_OUT,
829 &desc->flags, !gc->get_direction(gc, i));
830 } else {
831 assign_bit(FLAG_IS_OUT,
832 &desc->flags, !gc->direction_input);
833 }
834 }
835
836 ret = gpiochip_add_pin_ranges(gc);
837 if (ret)
838 goto err_remove_of_chip;
839
840 acpi_gpiochip_add(gc);
841
842 machine_gpiochip_add(gc);
843
844 ret = gpiochip_irqchip_init_valid_mask(gc);
845 if (ret)
846 goto err_remove_acpi_chip;
847
848 ret = gpiochip_irqchip_init_hw(gc);
849 if (ret)
850 goto err_remove_acpi_chip;
851
852 ret = gpiochip_add_irqchip(gc, lock_key, request_key);
853 if (ret)
854 goto err_remove_irqchip_mask;
855
856 /*
857 * By first adding the chardev, and then adding the device,
858 * we get a device node entry in sysfs under
859 * /sys/bus/gpio/devices/gpiochipN/dev that can be used for
860 * coldplug of device nodes and other udev business.
861 * We can do this only if gpiolib has been initialized.
862 * Otherwise, defer until later.
863 */
864 if (gpiolib_initialized) {
865 ret = gpiochip_setup_dev(gdev);
866 if (ret)
867 goto err_remove_irqchip;
868 }
869 return 0;
870
871err_remove_irqchip:
872 gpiochip_irqchip_remove(gc);
873err_remove_irqchip_mask:
874 gpiochip_irqchip_free_valid_mask(gc);
875err_remove_acpi_chip:
876 acpi_gpiochip_remove(gc);
877err_remove_of_chip:
878 gpiochip_free_hogs(gc);
879 of_gpiochip_remove(gc);
880err_free_gpiochip_mask:
881 gpiochip_remove_pin_ranges(gc);
882 gpiochip_free_valid_mask(gc);
883 if (gdev->dev.release) {
884 /* release() has been registered by gpiochip_setup_dev() */
885 put_device(&gdev->dev);
886 goto err_print_message;
887 }
888err_remove_from_list:
889 spin_lock_irqsave(&gpio_lock, flags);
890 list_del(&gdev->list);
891 spin_unlock_irqrestore(&gpio_lock, flags);
892err_free_label:
893 kfree_const(gdev->label);
894err_free_descs:
895 kfree(gdev->descs);
896err_free_dev_name:
897 kfree(dev_name(&gdev->dev));
898err_free_ida:
899 ida_free(&gpio_ida, gdev->id);
900err_free_gdev:
901 kfree(gdev);
902err_print_message:
903 /* failures here can mean systems won't boot... */
904 if (ret != -EPROBE_DEFER) {
905 pr_err("%s: GPIOs %d..%d (%s) failed to register, %d\n", __func__,
906 base, base + (int)ngpios - 1,
907 gc->label ? : "generic", ret);
908 }
909 return ret;
910}
911EXPORT_SYMBOL_GPL(gpiochip_add_data_with_key);
912
913/**
914 * gpiochip_get_data() - get per-subdriver data for the chip
915 * @gc: GPIO chip
916 *
917 * Returns:
918 * The per-subdriver data for the chip.
919 */
920void *gpiochip_get_data(struct gpio_chip *gc)
921{
922 return gc->gpiodev->data;
923}
924EXPORT_SYMBOL_GPL(gpiochip_get_data);
925
926/**
927 * gpiochip_remove() - unregister a gpio_chip
928 * @gc: the chip to unregister
929 *
930 * A gpio_chip with any GPIOs still requested may not be removed.
931 */
932void gpiochip_remove(struct gpio_chip *gc)
933{
934 struct gpio_device *gdev = gc->gpiodev;
935 unsigned long flags;
936 unsigned int i;
937
938 down_write(&gdev->sem);
939
940 /* FIXME: should the legacy sysfs handling be moved to gpio_device? */
941 gpiochip_sysfs_unregister(gdev);
942 gpiochip_free_hogs(gc);
943 /* Numb the device, cancelling all outstanding operations */
944 gdev->chip = NULL;
945 gpiochip_irqchip_remove(gc);
946 acpi_gpiochip_remove(gc);
947 of_gpiochip_remove(gc);
948 gpiochip_remove_pin_ranges(gc);
949 gpiochip_free_valid_mask(gc);
950 /*
951 * We accept no more calls into the driver from this point, so
952 * NULL the driver data pointer
953 */
954 gdev->data = NULL;
955
956 spin_lock_irqsave(&gpio_lock, flags);
957 for (i = 0; i < gdev->ngpio; i++) {
958 if (gpiochip_is_requested(gc, i))
959 break;
960 }
961 spin_unlock_irqrestore(&gpio_lock, flags);
962
963 if (i != gdev->ngpio)
964 dev_crit(&gdev->dev,
965 "REMOVING GPIOCHIP WITH GPIOS STILL REQUESTED\n");
966
967 /*
968 * The gpiochip side puts its use of the device to rest here:
969 * if there are no userspace clients, the chardev and device will
970 * be removed, else it will be dangling until the last user is
971 * gone.
972 */
973 gcdev_unregister(gdev);
974 up_write(&gdev->sem);
975 put_device(&gdev->dev);
976}
977EXPORT_SYMBOL_GPL(gpiochip_remove);
978
979/**
980 * gpiochip_find() - iterator for locating a specific gpio_chip
981 * @data: data to pass to match function
982 * @match: Callback function to check gpio_chip
983 *
984 * Similar to bus_find_device. It returns a reference to a gpio_chip as
985 * determined by a user supplied @match callback. The callback should return
986 * 0 if the device doesn't match and non-zero if it does. If the callback is
987 * non-zero, this function will return to the caller and not iterate over any
988 * more gpio_chips.
989 */
990struct gpio_chip *gpiochip_find(void *data,
991 int (*match)(struct gpio_chip *gc,
992 void *data))
993{
994 struct gpio_device *gdev;
995 struct gpio_chip *gc = NULL;
996 unsigned long flags;
997
998 spin_lock_irqsave(&gpio_lock, flags);
999 list_for_each_entry(gdev, &gpio_devices, list)
1000 if (gdev->chip && match(gdev->chip, data)) {
1001 gc = gdev->chip;
1002 break;
1003 }
1004
1005 spin_unlock_irqrestore(&gpio_lock, flags);
1006
1007 return gc;
1008}
1009EXPORT_SYMBOL_GPL(gpiochip_find);
1010
1011static int gpiochip_match_name(struct gpio_chip *gc, void *data)
1012{
1013 const char *name = data;
1014
1015 return !strcmp(gc->label, name);
1016}
1017
1018static struct gpio_chip *find_chip_by_name(const char *name)
1019{
1020 return gpiochip_find((void *)name, gpiochip_match_name);
1021}
1022
1023#ifdef CONFIG_GPIOLIB_IRQCHIP
1024
1025/*
1026 * The following is irqchip helper code for gpiochips.
1027 */
1028
1029static int gpiochip_irqchip_init_hw(struct gpio_chip *gc)
1030{
1031 struct gpio_irq_chip *girq = &gc->irq;
1032
1033 if (!girq->init_hw)
1034 return 0;
1035
1036 return girq->init_hw(gc);
1037}
1038
1039static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gc)
1040{
1041 struct gpio_irq_chip *girq = &gc->irq;
1042
1043 if (!girq->init_valid_mask)
1044 return 0;
1045
1046 girq->valid_mask = gpiochip_allocate_mask(gc);
1047 if (!girq->valid_mask)
1048 return -ENOMEM;
1049
1050 girq->init_valid_mask(gc, girq->valid_mask, gc->ngpio);
1051
1052 return 0;
1053}
1054
1055static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gc)
1056{
1057 bitmap_free(gc->irq.valid_mask);
1058 gc->irq.valid_mask = NULL;
1059}
1060
1061bool gpiochip_irqchip_irq_valid(const struct gpio_chip *gc,
1062 unsigned int offset)
1063{
1064 if (!gpiochip_line_is_valid(gc, offset))
1065 return false;
1066 /* No mask means all valid */
1067 if (likely(!gc->irq.valid_mask))
1068 return true;
1069 return test_bit(offset, gc->irq.valid_mask);
1070}
1071EXPORT_SYMBOL_GPL(gpiochip_irqchip_irq_valid);
1072
1073#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
1074
1075/**
1076 * gpiochip_set_hierarchical_irqchip() - connects a hierarchical irqchip
1077 * to a gpiochip
1078 * @gc: the gpiochip to set the irqchip hierarchical handler to
1079 * @irqchip: the irqchip to handle this level of the hierarchy, the interrupt
1080 * will then percolate up to the parent
1081 */
1082static void gpiochip_set_hierarchical_irqchip(struct gpio_chip *gc,
1083 struct irq_chip *irqchip)
1084{
1085 /* DT will deal with mapping each IRQ as we go along */
1086 if (is_of_node(gc->irq.fwnode))
1087 return;
1088
1089 /*
1090 * This is for legacy and boardfile "irqchip" fwnodes: allocate
1091 * irqs upfront instead of dynamically since we don't have the
1092 * dynamic type of allocation that hardware description languages
1093 * provide. Once all GPIO drivers using board files are gone from
1094 * the kernel we can delete this code, but for a transitional period
1095 * it is necessary to keep this around.
1096 */
1097 if (is_fwnode_irqchip(gc->irq.fwnode)) {
1098 int i;
1099 int ret;
1100
1101 for (i = 0; i < gc->ngpio; i++) {
1102 struct irq_fwspec fwspec;
1103 unsigned int parent_hwirq;
1104 unsigned int parent_type;
1105 struct gpio_irq_chip *girq = &gc->irq;
1106
1107 /*
1108 * We call the child to parent translation function
1109 * only to check if the child IRQ is valid or not.
1110 * Just pick the rising edge type here as that is what
1111 * we likely need to support.
1112 */
1113 ret = girq->child_to_parent_hwirq(gc, i,
1114 IRQ_TYPE_EDGE_RISING,
1115 &parent_hwirq,
1116 &parent_type);
1117 if (ret) {
1118 chip_err(gc, "skip set-up on hwirq %d\n",
1119 i);
1120 continue;
1121 }
1122
1123 fwspec.fwnode = gc->irq.fwnode;
1124 /* This is the hwirq for the GPIO line side of things */
1125 fwspec.param[0] = girq->child_offset_to_irq(gc, i);
1126 /* Just pick something */
1127 fwspec.param[1] = IRQ_TYPE_EDGE_RISING;
1128 fwspec.param_count = 2;
1129 ret = __irq_domain_alloc_irqs(gc->irq.domain,
1130 /* just pick something */
1131 -1,
1132 1,
1133 NUMA_NO_NODE,
1134 &fwspec,
1135 false,
1136 NULL);
1137 if (ret < 0) {
1138 chip_err(gc,
1139 "can not allocate irq for GPIO line %d parent hwirq %d in hierarchy domain: %d\n",
1140 i, parent_hwirq,
1141 ret);
1142 }
1143 }
1144 }
1145
1146 chip_err(gc, "%s unknown fwnode type proceed anyway\n", __func__);
1147
1148 return;
1149}
1150
1151static int gpiochip_hierarchy_irq_domain_translate(struct irq_domain *d,
1152 struct irq_fwspec *fwspec,
1153 unsigned long *hwirq,
1154 unsigned int *type)
1155{
1156 /* We support standard DT translation */
1157 if (is_of_node(fwspec->fwnode) && fwspec->param_count == 2) {
1158 return irq_domain_translate_twocell(d, fwspec, hwirq, type);
1159 }
1160
1161 /* This is for board files and others not using DT */
1162 if (is_fwnode_irqchip(fwspec->fwnode)) {
1163 int ret;
1164
1165 ret = irq_domain_translate_twocell(d, fwspec, hwirq, type);
1166 if (ret)
1167 return ret;
1168 WARN_ON(*type == IRQ_TYPE_NONE);
1169 return 0;
1170 }
1171 return -EINVAL;
1172}
1173
1174static int gpiochip_hierarchy_irq_domain_alloc(struct irq_domain *d,
1175 unsigned int irq,
1176 unsigned int nr_irqs,
1177 void *data)
1178{
1179 struct gpio_chip *gc = d->host_data;
1180 irq_hw_number_t hwirq;
1181 unsigned int type = IRQ_TYPE_NONE;
1182 struct irq_fwspec *fwspec = data;
1183 union gpio_irq_fwspec gpio_parent_fwspec = {};
1184 unsigned int parent_hwirq;
1185 unsigned int parent_type;
1186 struct gpio_irq_chip *girq = &gc->irq;
1187 int ret;
1188
1189 /*
1190 * The nr_irqs parameter is always one except for PCI multi-MSI
1191 * so this should not happen.
1192 */
1193 WARN_ON(nr_irqs != 1);
1194
1195 ret = gc->irq.child_irq_domain_ops.translate(d, fwspec, &hwirq, &type);
1196 if (ret)
1197 return ret;
1198
1199 chip_dbg(gc, "allocate IRQ %d, hwirq %lu\n", irq, hwirq);
1200
1201 ret = girq->child_to_parent_hwirq(gc, hwirq, type,
1202 &parent_hwirq, &parent_type);
1203 if (ret) {
1204 chip_err(gc, "can't look up hwirq %lu\n", hwirq);
1205 return ret;
1206 }
1207 chip_dbg(gc, "found parent hwirq %u\n", parent_hwirq);
1208
1209 /*
1210 * We set handle_bad_irq because the .set_type() should
1211 * always be invoked and set the right type of handler.
1212 */
1213 irq_domain_set_info(d,
1214 irq,
1215 hwirq,
1216 gc->irq.chip,
1217 gc,
1218 girq->handler,
1219 NULL, NULL);
1220 irq_set_probe(irq);
1221
1222 /* This parent only handles asserted level IRQs */
1223 ret = girq->populate_parent_alloc_arg(gc, &gpio_parent_fwspec,
1224 parent_hwirq, parent_type);
1225 if (ret)
1226 return ret;
1227
1228 chip_dbg(gc, "alloc_irqs_parent for %d parent hwirq %d\n",
1229 irq, parent_hwirq);
1230 irq_set_lockdep_class(irq, gc->irq.lock_key, gc->irq.request_key);
1231 ret = irq_domain_alloc_irqs_parent(d, irq, 1, &gpio_parent_fwspec);
1232 /*
1233 * If the parent irqdomain is msi, the interrupts have already
1234 * been allocated, so the EEXIST is good.
1235 */
1236 if (irq_domain_is_msi(d->parent) && (ret == -EEXIST))
1237 ret = 0;
1238 if (ret)
1239 chip_err(gc,
1240 "failed to allocate parent hwirq %d for hwirq %lu\n",
1241 parent_hwirq, hwirq);
1242
1243 return ret;
1244}
1245
1246static unsigned int gpiochip_child_offset_to_irq_noop(struct gpio_chip *gc,
1247 unsigned int offset)
1248{
1249 return offset;
1250}
1251
1252static void gpiochip_hierarchy_setup_domain_ops(struct irq_domain_ops *ops)
1253{
1254 ops->activate = gpiochip_irq_domain_activate;
1255 ops->deactivate = gpiochip_irq_domain_deactivate;
1256 ops->alloc = gpiochip_hierarchy_irq_domain_alloc;
1257
1258 /*
1259 * We only allow overriding the translate() and free() functions for
1260 * hierarchical chips, and this should only be done if the user
1261 * really need something other than 1:1 translation for translate()
1262 * callback and free if user wants to free up any resources which
1263 * were allocated during callbacks, for example populate_parent_alloc_arg.
1264 */
1265 if (!ops->translate)
1266 ops->translate = gpiochip_hierarchy_irq_domain_translate;
1267 if (!ops->free)
1268 ops->free = irq_domain_free_irqs_common;
1269}
1270
1271static int gpiochip_hierarchy_add_domain(struct gpio_chip *gc)
1272{
1273 if (!gc->irq.child_to_parent_hwirq ||
1274 !gc->irq.fwnode) {
1275 chip_err(gc, "missing irqdomain vital data\n");
1276 return -EINVAL;
1277 }
1278
1279 if (!gc->irq.child_offset_to_irq)
1280 gc->irq.child_offset_to_irq = gpiochip_child_offset_to_irq_noop;
1281
1282 if (!gc->irq.populate_parent_alloc_arg)
1283 gc->irq.populate_parent_alloc_arg =
1284 gpiochip_populate_parent_fwspec_twocell;
1285
1286 gpiochip_hierarchy_setup_domain_ops(&gc->irq.child_irq_domain_ops);
1287
1288 gc->irq.domain = irq_domain_create_hierarchy(
1289 gc->irq.parent_domain,
1290 0,
1291 gc->ngpio,
1292 gc->irq.fwnode,
1293 &gc->irq.child_irq_domain_ops,
1294 gc);
1295
1296 if (!gc->irq.domain)
1297 return -ENOMEM;
1298
1299 gpiochip_set_hierarchical_irqchip(gc, gc->irq.chip);
1300
1301 return 0;
1302}
1303
1304static bool gpiochip_hierarchy_is_hierarchical(struct gpio_chip *gc)
1305{
1306 return !!gc->irq.parent_domain;
1307}
1308
1309int gpiochip_populate_parent_fwspec_twocell(struct gpio_chip *gc,
1310 union gpio_irq_fwspec *gfwspec,
1311 unsigned int parent_hwirq,
1312 unsigned int parent_type)
1313{
1314 struct irq_fwspec *fwspec = &gfwspec->fwspec;
1315
1316 fwspec->fwnode = gc->irq.parent_domain->fwnode;
1317 fwspec->param_count = 2;
1318 fwspec->param[0] = parent_hwirq;
1319 fwspec->param[1] = parent_type;
1320
1321 return 0;
1322}
1323EXPORT_SYMBOL_GPL(gpiochip_populate_parent_fwspec_twocell);
1324
1325int gpiochip_populate_parent_fwspec_fourcell(struct gpio_chip *gc,
1326 union gpio_irq_fwspec *gfwspec,
1327 unsigned int parent_hwirq,
1328 unsigned int parent_type)
1329{
1330 struct irq_fwspec *fwspec = &gfwspec->fwspec;
1331
1332 fwspec->fwnode = gc->irq.parent_domain->fwnode;
1333 fwspec->param_count = 4;
1334 fwspec->param[0] = 0;
1335 fwspec->param[1] = parent_hwirq;
1336 fwspec->param[2] = 0;
1337 fwspec->param[3] = parent_type;
1338
1339 return 0;
1340}
1341EXPORT_SYMBOL_GPL(gpiochip_populate_parent_fwspec_fourcell);
1342
1343#else
1344
1345static int gpiochip_hierarchy_add_domain(struct gpio_chip *gc)
1346{
1347 return -EINVAL;
1348}
1349
1350static bool gpiochip_hierarchy_is_hierarchical(struct gpio_chip *gc)
1351{
1352 return false;
1353}
1354
1355#endif /* CONFIG_IRQ_DOMAIN_HIERARCHY */
1356
1357/**
1358 * gpiochip_irq_map() - maps an IRQ into a GPIO irqchip
1359 * @d: the irqdomain used by this irqchip
1360 * @irq: the global irq number used by this GPIO irqchip irq
1361 * @hwirq: the local IRQ/GPIO line offset on this gpiochip
1362 *
1363 * This function will set up the mapping for a certain IRQ line on a
1364 * gpiochip by assigning the gpiochip as chip data, and using the irqchip
1365 * stored inside the gpiochip.
1366 */
1367int gpiochip_irq_map(struct irq_domain *d, unsigned int irq,
1368 irq_hw_number_t hwirq)
1369{
1370 struct gpio_chip *gc = d->host_data;
1371 int ret = 0;
1372
1373 if (!gpiochip_irqchip_irq_valid(gc, hwirq))
1374 return -ENXIO;
1375
1376 irq_set_chip_data(irq, gc);
1377 /*
1378 * This lock class tells lockdep that GPIO irqs are in a different
1379 * category than their parents, so it won't report false recursion.
1380 */
1381 irq_set_lockdep_class(irq, gc->irq.lock_key, gc->irq.request_key);
1382 irq_set_chip_and_handler(irq, gc->irq.chip, gc->irq.handler);
1383 /* Chips that use nested thread handlers have them marked */
1384 if (gc->irq.threaded)
1385 irq_set_nested_thread(irq, 1);
1386 irq_set_noprobe(irq);
1387
1388 if (gc->irq.num_parents == 1)
1389 ret = irq_set_parent(irq, gc->irq.parents[0]);
1390 else if (gc->irq.map)
1391 ret = irq_set_parent(irq, gc->irq.map[hwirq]);
1392
1393 if (ret < 0)
1394 return ret;
1395
1396 /*
1397 * No set-up of the hardware will happen if IRQ_TYPE_NONE
1398 * is passed as default type.
1399 */
1400 if (gc->irq.default_type != IRQ_TYPE_NONE)
1401 irq_set_irq_type(irq, gc->irq.default_type);
1402
1403 return 0;
1404}
1405EXPORT_SYMBOL_GPL(gpiochip_irq_map);
1406
1407void gpiochip_irq_unmap(struct irq_domain *d, unsigned int irq)
1408{
1409 struct gpio_chip *gc = d->host_data;
1410
1411 if (gc->irq.threaded)
1412 irq_set_nested_thread(irq, 0);
1413 irq_set_chip_and_handler(irq, NULL, NULL);
1414 irq_set_chip_data(irq, NULL);
1415}
1416EXPORT_SYMBOL_GPL(gpiochip_irq_unmap);
1417
1418static const struct irq_domain_ops gpiochip_domain_ops = {
1419 .map = gpiochip_irq_map,
1420 .unmap = gpiochip_irq_unmap,
1421 /* Virtually all GPIO irqchips are twocell:ed */
1422 .xlate = irq_domain_xlate_twocell,
1423};
1424
1425/*
1426 * TODO: move these activate/deactivate in under the hierarchicial
1427 * irqchip implementation as static once SPMI and SSBI (all external
1428 * users) are phased over.
1429 */
1430/**
1431 * gpiochip_irq_domain_activate() - Lock a GPIO to be used as an IRQ
1432 * @domain: The IRQ domain used by this IRQ chip
1433 * @data: Outermost irq_data associated with the IRQ
1434 * @reserve: If set, only reserve an interrupt vector instead of assigning one
1435 *
1436 * This function is a wrapper that calls gpiochip_lock_as_irq() and is to be
1437 * used as the activate function for the &struct irq_domain_ops. The host_data
1438 * for the IRQ domain must be the &struct gpio_chip.
1439 */
1440int gpiochip_irq_domain_activate(struct irq_domain *domain,
1441 struct irq_data *data, bool reserve)
1442{
1443 struct gpio_chip *gc = domain->host_data;
1444
1445 return gpiochip_lock_as_irq(gc, data->hwirq);
1446}
1447EXPORT_SYMBOL_GPL(gpiochip_irq_domain_activate);
1448
1449/**
1450 * gpiochip_irq_domain_deactivate() - Unlock a GPIO used as an IRQ
1451 * @domain: The IRQ domain used by this IRQ chip
1452 * @data: Outermost irq_data associated with the IRQ
1453 *
1454 * This function is a wrapper that will call gpiochip_unlock_as_irq() and is to
1455 * be used as the deactivate function for the &struct irq_domain_ops. The
1456 * host_data for the IRQ domain must be the &struct gpio_chip.
1457 */
1458void gpiochip_irq_domain_deactivate(struct irq_domain *domain,
1459 struct irq_data *data)
1460{
1461 struct gpio_chip *gc = domain->host_data;
1462
1463 return gpiochip_unlock_as_irq(gc, data->hwirq);
1464}
1465EXPORT_SYMBOL_GPL(gpiochip_irq_domain_deactivate);
1466
1467static int gpiochip_to_irq(struct gpio_chip *gc, unsigned int offset)
1468{
1469 struct irq_domain *domain = gc->irq.domain;
1470
1471#ifdef CONFIG_GPIOLIB_IRQCHIP
1472 /*
1473 * Avoid race condition with other code, which tries to lookup
1474 * an IRQ before the irqchip has been properly registered,
1475 * i.e. while gpiochip is still being brought up.
1476 */
1477 if (!gc->irq.initialized)
1478 return -EPROBE_DEFER;
1479#endif
1480
1481 if (!gpiochip_irqchip_irq_valid(gc, offset))
1482 return -ENXIO;
1483
1484#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
1485 if (irq_domain_is_hierarchy(domain)) {
1486 struct irq_fwspec spec;
1487
1488 spec.fwnode = domain->fwnode;
1489 spec.param_count = 2;
1490 spec.param[0] = gc->irq.child_offset_to_irq(gc, offset);
1491 spec.param[1] = IRQ_TYPE_NONE;
1492
1493 return irq_create_fwspec_mapping(&spec);
1494 }
1495#endif
1496
1497 return irq_create_mapping(domain, offset);
1498}
1499
1500int gpiochip_irq_reqres(struct irq_data *d)
1501{
1502 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1503
1504 return gpiochip_reqres_irq(gc, d->hwirq);
1505}
1506EXPORT_SYMBOL(gpiochip_irq_reqres);
1507
1508void gpiochip_irq_relres(struct irq_data *d)
1509{
1510 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1511
1512 gpiochip_relres_irq(gc, d->hwirq);
1513}
1514EXPORT_SYMBOL(gpiochip_irq_relres);
1515
1516static void gpiochip_irq_mask(struct irq_data *d)
1517{
1518 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1519
1520 if (gc->irq.irq_mask)
1521 gc->irq.irq_mask(d);
1522 gpiochip_disable_irq(gc, d->hwirq);
1523}
1524
1525static void gpiochip_irq_unmask(struct irq_data *d)
1526{
1527 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1528
1529 gpiochip_enable_irq(gc, d->hwirq);
1530 if (gc->irq.irq_unmask)
1531 gc->irq.irq_unmask(d);
1532}
1533
1534static void gpiochip_irq_enable(struct irq_data *d)
1535{
1536 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1537
1538 gpiochip_enable_irq(gc, d->hwirq);
1539 gc->irq.irq_enable(d);
1540}
1541
1542static void gpiochip_irq_disable(struct irq_data *d)
1543{
1544 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1545
1546 gc->irq.irq_disable(d);
1547 gpiochip_disable_irq(gc, d->hwirq);
1548}
1549
1550static void gpiochip_set_irq_hooks(struct gpio_chip *gc)
1551{
1552 struct irq_chip *irqchip = gc->irq.chip;
1553
1554 if (irqchip->flags & IRQCHIP_IMMUTABLE)
1555 return;
1556
1557 chip_warn(gc, "not an immutable chip, please consider fixing it!\n");
1558
1559 if (!irqchip->irq_request_resources &&
1560 !irqchip->irq_release_resources) {
1561 irqchip->irq_request_resources = gpiochip_irq_reqres;
1562 irqchip->irq_release_resources = gpiochip_irq_relres;
1563 }
1564 if (WARN_ON(gc->irq.irq_enable))
1565 return;
1566 /* Check if the irqchip already has this hook... */
1567 if (irqchip->irq_enable == gpiochip_irq_enable ||
1568 irqchip->irq_mask == gpiochip_irq_mask) {
1569 /*
1570 * ...and if so, give a gentle warning that this is bad
1571 * practice.
1572 */
1573 chip_info(gc,
1574 "detected irqchip that is shared with multiple gpiochips: please fix the driver.\n");
1575 return;
1576 }
1577
1578 if (irqchip->irq_disable) {
1579 gc->irq.irq_disable = irqchip->irq_disable;
1580 irqchip->irq_disable = gpiochip_irq_disable;
1581 } else {
1582 gc->irq.irq_mask = irqchip->irq_mask;
1583 irqchip->irq_mask = gpiochip_irq_mask;
1584 }
1585
1586 if (irqchip->irq_enable) {
1587 gc->irq.irq_enable = irqchip->irq_enable;
1588 irqchip->irq_enable = gpiochip_irq_enable;
1589 } else {
1590 gc->irq.irq_unmask = irqchip->irq_unmask;
1591 irqchip->irq_unmask = gpiochip_irq_unmask;
1592 }
1593}
1594
1595/**
1596 * gpiochip_add_irqchip() - adds an IRQ chip to a GPIO chip
1597 * @gc: the GPIO chip to add the IRQ chip to
1598 * @lock_key: lockdep class for IRQ lock
1599 * @request_key: lockdep class for IRQ request
1600 */
1601static int gpiochip_add_irqchip(struct gpio_chip *gc,
1602 struct lock_class_key *lock_key,
1603 struct lock_class_key *request_key)
1604{
1605 struct fwnode_handle *fwnode = dev_fwnode(&gc->gpiodev->dev);
1606 struct irq_chip *irqchip = gc->irq.chip;
1607 unsigned int type;
1608 unsigned int i;
1609
1610 if (!irqchip)
1611 return 0;
1612
1613 if (gc->irq.parent_handler && gc->can_sleep) {
1614 chip_err(gc, "you cannot have chained interrupts on a chip that may sleep\n");
1615 return -EINVAL;
1616 }
1617
1618 type = gc->irq.default_type;
1619
1620 /*
1621 * Specifying a default trigger is a terrible idea if DT or ACPI is
1622 * used to configure the interrupts, as you may end up with
1623 * conflicting triggers. Tell the user, and reset to NONE.
1624 */
1625 if (WARN(fwnode && type != IRQ_TYPE_NONE,
1626 "%pfw: Ignoring %u default trigger\n", fwnode, type))
1627 type = IRQ_TYPE_NONE;
1628
1629 if (gc->to_irq)
1630 chip_warn(gc, "to_irq is redefined in %s and you shouldn't rely on it\n", __func__);
1631
1632 gc->to_irq = gpiochip_to_irq;
1633 gc->irq.default_type = type;
1634 gc->irq.lock_key = lock_key;
1635 gc->irq.request_key = request_key;
1636
1637 /* If a parent irqdomain is provided, let's build a hierarchy */
1638 if (gpiochip_hierarchy_is_hierarchical(gc)) {
1639 int ret = gpiochip_hierarchy_add_domain(gc);
1640 if (ret)
1641 return ret;
1642 } else {
1643 /* Some drivers provide custom irqdomain ops */
1644 gc->irq.domain = irq_domain_create_simple(fwnode,
1645 gc->ngpio,
1646 gc->irq.first,
1647 gc->irq.domain_ops ?: &gpiochip_domain_ops,
1648 gc);
1649 if (!gc->irq.domain)
1650 return -EINVAL;
1651 }
1652
1653 if (gc->irq.parent_handler) {
1654 for (i = 0; i < gc->irq.num_parents; i++) {
1655 void *data;
1656
1657 if (gc->irq.per_parent_data)
1658 data = gc->irq.parent_handler_data_array[i];
1659 else
1660 data = gc->irq.parent_handler_data ?: gc;
1661
1662 /*
1663 * The parent IRQ chip is already using the chip_data
1664 * for this IRQ chip, so our callbacks simply use the
1665 * handler_data.
1666 */
1667 irq_set_chained_handler_and_data(gc->irq.parents[i],
1668 gc->irq.parent_handler,
1669 data);
1670 }
1671 }
1672
1673 gpiochip_set_irq_hooks(gc);
1674
1675 /*
1676 * Using barrier() here to prevent compiler from reordering
1677 * gc->irq.initialized before initialization of above
1678 * GPIO chip irq members.
1679 */
1680 barrier();
1681
1682 gc->irq.initialized = true;
1683
1684 acpi_gpiochip_request_interrupts(gc);
1685
1686 return 0;
1687}
1688
1689/**
1690 * gpiochip_irqchip_remove() - removes an irqchip added to a gpiochip
1691 * @gc: the gpiochip to remove the irqchip from
1692 *
1693 * This is called only from gpiochip_remove()
1694 */
1695static void gpiochip_irqchip_remove(struct gpio_chip *gc)
1696{
1697 struct irq_chip *irqchip = gc->irq.chip;
1698 unsigned int offset;
1699
1700 acpi_gpiochip_free_interrupts(gc);
1701
1702 if (irqchip && gc->irq.parent_handler) {
1703 struct gpio_irq_chip *irq = &gc->irq;
1704 unsigned int i;
1705
1706 for (i = 0; i < irq->num_parents; i++)
1707 irq_set_chained_handler_and_data(irq->parents[i],
1708 NULL, NULL);
1709 }
1710
1711 /* Remove all IRQ mappings and delete the domain */
1712 if (gc->irq.domain) {
1713 unsigned int irq;
1714
1715 for (offset = 0; offset < gc->ngpio; offset++) {
1716 if (!gpiochip_irqchip_irq_valid(gc, offset))
1717 continue;
1718
1719 irq = irq_find_mapping(gc->irq.domain, offset);
1720 irq_dispose_mapping(irq);
1721 }
1722
1723 irq_domain_remove(gc->irq.domain);
1724 }
1725
1726 if (irqchip && !(irqchip->flags & IRQCHIP_IMMUTABLE)) {
1727 if (irqchip->irq_request_resources == gpiochip_irq_reqres) {
1728 irqchip->irq_request_resources = NULL;
1729 irqchip->irq_release_resources = NULL;
1730 }
1731 if (irqchip->irq_enable == gpiochip_irq_enable) {
1732 irqchip->irq_enable = gc->irq.irq_enable;
1733 irqchip->irq_disable = gc->irq.irq_disable;
1734 }
1735 }
1736 gc->irq.irq_enable = NULL;
1737 gc->irq.irq_disable = NULL;
1738 gc->irq.chip = NULL;
1739
1740 gpiochip_irqchip_free_valid_mask(gc);
1741}
1742
1743/**
1744 * gpiochip_irqchip_add_domain() - adds an irqdomain to a gpiochip
1745 * @gc: the gpiochip to add the irqchip to
1746 * @domain: the irqdomain to add to the gpiochip
1747 *
1748 * This function adds an IRQ domain to the gpiochip.
1749 */
1750int gpiochip_irqchip_add_domain(struct gpio_chip *gc,
1751 struct irq_domain *domain)
1752{
1753 if (!domain)
1754 return -EINVAL;
1755
1756 gc->to_irq = gpiochip_to_irq;
1757 gc->irq.domain = domain;
1758
1759 return 0;
1760}
1761EXPORT_SYMBOL_GPL(gpiochip_irqchip_add_domain);
1762
1763#else /* CONFIG_GPIOLIB_IRQCHIP */
1764
1765static inline int gpiochip_add_irqchip(struct gpio_chip *gc,
1766 struct lock_class_key *lock_key,
1767 struct lock_class_key *request_key)
1768{
1769 return 0;
1770}
1771static void gpiochip_irqchip_remove(struct gpio_chip *gc) {}
1772
1773static inline int gpiochip_irqchip_init_hw(struct gpio_chip *gc)
1774{
1775 return 0;
1776}
1777
1778static inline int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gc)
1779{
1780 return 0;
1781}
1782static inline void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gc)
1783{ }
1784
1785#endif /* CONFIG_GPIOLIB_IRQCHIP */
1786
1787/**
1788 * gpiochip_generic_request() - request the gpio function for a pin
1789 * @gc: the gpiochip owning the GPIO
1790 * @offset: the offset of the GPIO to request for GPIO function
1791 */
1792int gpiochip_generic_request(struct gpio_chip *gc, unsigned int offset)
1793{
1794#ifdef CONFIG_PINCTRL
1795 if (list_empty(&gc->gpiodev->pin_ranges))
1796 return 0;
1797#endif
1798
1799 return pinctrl_gpio_request(gc->gpiodev->base + offset);
1800}
1801EXPORT_SYMBOL_GPL(gpiochip_generic_request);
1802
1803/**
1804 * gpiochip_generic_free() - free the gpio function from a pin
1805 * @gc: the gpiochip to request the gpio function for
1806 * @offset: the offset of the GPIO to free from GPIO function
1807 */
1808void gpiochip_generic_free(struct gpio_chip *gc, unsigned int offset)
1809{
1810#ifdef CONFIG_PINCTRL
1811 if (list_empty(&gc->gpiodev->pin_ranges))
1812 return;
1813#endif
1814
1815 pinctrl_gpio_free(gc->gpiodev->base + offset);
1816}
1817EXPORT_SYMBOL_GPL(gpiochip_generic_free);
1818
1819/**
1820 * gpiochip_generic_config() - apply configuration for a pin
1821 * @gc: the gpiochip owning the GPIO
1822 * @offset: the offset of the GPIO to apply the configuration
1823 * @config: the configuration to be applied
1824 */
1825int gpiochip_generic_config(struct gpio_chip *gc, unsigned int offset,
1826 unsigned long config)
1827{
1828 return pinctrl_gpio_set_config(gc->gpiodev->base + offset, config);
1829}
1830EXPORT_SYMBOL_GPL(gpiochip_generic_config);
1831
1832#ifdef CONFIG_PINCTRL
1833
1834/**
1835 * gpiochip_add_pingroup_range() - add a range for GPIO <-> pin mapping
1836 * @gc: the gpiochip to add the range for
1837 * @pctldev: the pin controller to map to
1838 * @gpio_offset: the start offset in the current gpio_chip number space
1839 * @pin_group: name of the pin group inside the pin controller
1840 *
1841 * Calling this function directly from a DeviceTree-supported
1842 * pinctrl driver is DEPRECATED. Please see Section 2.1 of
1843 * Documentation/devicetree/bindings/gpio/gpio.txt on how to
1844 * bind pinctrl and gpio drivers via the "gpio-ranges" property.
1845 */
1846int gpiochip_add_pingroup_range(struct gpio_chip *gc,
1847 struct pinctrl_dev *pctldev,
1848 unsigned int gpio_offset, const char *pin_group)
1849{
1850 struct gpio_pin_range *pin_range;
1851 struct gpio_device *gdev = gc->gpiodev;
1852 int ret;
1853
1854 pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL);
1855 if (!pin_range) {
1856 chip_err(gc, "failed to allocate pin ranges\n");
1857 return -ENOMEM;
1858 }
1859
1860 /* Use local offset as range ID */
1861 pin_range->range.id = gpio_offset;
1862 pin_range->range.gc = gc;
1863 pin_range->range.name = gc->label;
1864 pin_range->range.base = gdev->base + gpio_offset;
1865 pin_range->pctldev = pctldev;
1866
1867 ret = pinctrl_get_group_pins(pctldev, pin_group,
1868 &pin_range->range.pins,
1869 &pin_range->range.npins);
1870 if (ret < 0) {
1871 kfree(pin_range);
1872 return ret;
1873 }
1874
1875 pinctrl_add_gpio_range(pctldev, &pin_range->range);
1876
1877 chip_dbg(gc, "created GPIO range %d->%d ==> %s PINGRP %s\n",
1878 gpio_offset, gpio_offset + pin_range->range.npins - 1,
1879 pinctrl_dev_get_devname(pctldev), pin_group);
1880
1881 list_add_tail(&pin_range->node, &gdev->pin_ranges);
1882
1883 return 0;
1884}
1885EXPORT_SYMBOL_GPL(gpiochip_add_pingroup_range);
1886
1887/**
1888 * gpiochip_add_pin_range() - add a range for GPIO <-> pin mapping
1889 * @gc: the gpiochip to add the range for
1890 * @pinctl_name: the dev_name() of the pin controller to map to
1891 * @gpio_offset: the start offset in the current gpio_chip number space
1892 * @pin_offset: the start offset in the pin controller number space
1893 * @npins: the number of pins from the offset of each pin space (GPIO and
1894 * pin controller) to accumulate in this range
1895 *
1896 * Returns:
1897 * 0 on success, or a negative error-code on failure.
1898 *
1899 * Calling this function directly from a DeviceTree-supported
1900 * pinctrl driver is DEPRECATED. Please see Section 2.1 of
1901 * Documentation/devicetree/bindings/gpio/gpio.txt on how to
1902 * bind pinctrl and gpio drivers via the "gpio-ranges" property.
1903 */
1904int gpiochip_add_pin_range(struct gpio_chip *gc, const char *pinctl_name,
1905 unsigned int gpio_offset, unsigned int pin_offset,
1906 unsigned int npins)
1907{
1908 struct gpio_pin_range *pin_range;
1909 struct gpio_device *gdev = gc->gpiodev;
1910 int ret;
1911
1912 pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL);
1913 if (!pin_range) {
1914 chip_err(gc, "failed to allocate pin ranges\n");
1915 return -ENOMEM;
1916 }
1917
1918 /* Use local offset as range ID */
1919 pin_range->range.id = gpio_offset;
1920 pin_range->range.gc = gc;
1921 pin_range->range.name = gc->label;
1922 pin_range->range.base = gdev->base + gpio_offset;
1923 pin_range->range.pin_base = pin_offset;
1924 pin_range->range.npins = npins;
1925 pin_range->pctldev = pinctrl_find_and_add_gpio_range(pinctl_name,
1926 &pin_range->range);
1927 if (IS_ERR(pin_range->pctldev)) {
1928 ret = PTR_ERR(pin_range->pctldev);
1929 chip_err(gc, "could not create pin range\n");
1930 kfree(pin_range);
1931 return ret;
1932 }
1933 chip_dbg(gc, "created GPIO range %d->%d ==> %s PIN %d->%d\n",
1934 gpio_offset, gpio_offset + npins - 1,
1935 pinctl_name,
1936 pin_offset, pin_offset + npins - 1);
1937
1938 list_add_tail(&pin_range->node, &gdev->pin_ranges);
1939
1940 return 0;
1941}
1942EXPORT_SYMBOL_GPL(gpiochip_add_pin_range);
1943
1944/**
1945 * gpiochip_remove_pin_ranges() - remove all the GPIO <-> pin mappings
1946 * @gc: the chip to remove all the mappings for
1947 */
1948void gpiochip_remove_pin_ranges(struct gpio_chip *gc)
1949{
1950 struct gpio_pin_range *pin_range, *tmp;
1951 struct gpio_device *gdev = gc->gpiodev;
1952
1953 list_for_each_entry_safe(pin_range, tmp, &gdev->pin_ranges, node) {
1954 list_del(&pin_range->node);
1955 pinctrl_remove_gpio_range(pin_range->pctldev,
1956 &pin_range->range);
1957 kfree(pin_range);
1958 }
1959}
1960EXPORT_SYMBOL_GPL(gpiochip_remove_pin_ranges);
1961
1962#endif /* CONFIG_PINCTRL */
1963
1964/* These "optional" allocation calls help prevent drivers from stomping
1965 * on each other, and help provide better diagnostics in debugfs.
1966 * They're called even less than the "set direction" calls.
1967 */
1968static int gpiod_request_commit(struct gpio_desc *desc, const char *label)
1969{
1970 struct gpio_chip *gc = desc->gdev->chip;
1971 int ret;
1972 unsigned long flags;
1973 unsigned offset;
1974
1975 if (label) {
1976 label = kstrdup_const(label, GFP_KERNEL);
1977 if (!label)
1978 return -ENOMEM;
1979 }
1980
1981 spin_lock_irqsave(&gpio_lock, flags);
1982
1983 /* NOTE: gpio_request() can be called in early boot,
1984 * before IRQs are enabled, for non-sleeping (SOC) GPIOs.
1985 */
1986
1987 if (test_and_set_bit(FLAG_REQUESTED, &desc->flags) == 0) {
1988 desc_set_label(desc, label ? : "?");
1989 } else {
1990 ret = -EBUSY;
1991 goto out_free_unlock;
1992 }
1993
1994 if (gc->request) {
1995 /* gc->request may sleep */
1996 spin_unlock_irqrestore(&gpio_lock, flags);
1997 offset = gpio_chip_hwgpio(desc);
1998 if (gpiochip_line_is_valid(gc, offset))
1999 ret = gc->request(gc, offset);
2000 else
2001 ret = -EINVAL;
2002 spin_lock_irqsave(&gpio_lock, flags);
2003
2004 if (ret) {
2005 desc_set_label(desc, NULL);
2006 clear_bit(FLAG_REQUESTED, &desc->flags);
2007 goto out_free_unlock;
2008 }
2009 }
2010 if (gc->get_direction) {
2011 /* gc->get_direction may sleep */
2012 spin_unlock_irqrestore(&gpio_lock, flags);
2013 gpiod_get_direction(desc);
2014 spin_lock_irqsave(&gpio_lock, flags);
2015 }
2016 spin_unlock_irqrestore(&gpio_lock, flags);
2017 return 0;
2018
2019out_free_unlock:
2020 spin_unlock_irqrestore(&gpio_lock, flags);
2021 kfree_const(label);
2022 return ret;
2023}
2024
2025/*
2026 * This descriptor validation needs to be inserted verbatim into each
2027 * function taking a descriptor, so we need to use a preprocessor
2028 * macro to avoid endless duplication. If the desc is NULL it is an
2029 * optional GPIO and calls should just bail out.
2030 */
2031static int validate_desc(const struct gpio_desc *desc, const char *func)
2032{
2033 if (!desc)
2034 return 0;
2035 if (IS_ERR(desc)) {
2036 pr_warn("%s: invalid GPIO (errorpointer)\n", func);
2037 return PTR_ERR(desc);
2038 }
2039 if (!desc->gdev) {
2040 pr_warn("%s: invalid GPIO (no device)\n", func);
2041 return -EINVAL;
2042 }
2043 if (!desc->gdev->chip) {
2044 dev_warn(&desc->gdev->dev,
2045 "%s: backing chip is gone\n", func);
2046 return 0;
2047 }
2048 return 1;
2049}
2050
2051#define VALIDATE_DESC(desc) do { \
2052 int __valid = validate_desc(desc, __func__); \
2053 if (__valid <= 0) \
2054 return __valid; \
2055 } while (0)
2056
2057#define VALIDATE_DESC_VOID(desc) do { \
2058 int __valid = validate_desc(desc, __func__); \
2059 if (__valid <= 0) \
2060 return; \
2061 } while (0)
2062
2063int gpiod_request(struct gpio_desc *desc, const char *label)
2064{
2065 int ret = -EPROBE_DEFER;
2066 struct gpio_device *gdev;
2067
2068 VALIDATE_DESC(desc);
2069 gdev = desc->gdev;
2070
2071 if (try_module_get(gdev->owner)) {
2072 ret = gpiod_request_commit(desc, label);
2073 if (ret)
2074 module_put(gdev->owner);
2075 else
2076 get_device(&gdev->dev);
2077 }
2078
2079 if (ret)
2080 gpiod_dbg(desc, "%s: status %d\n", __func__, ret);
2081
2082 return ret;
2083}
2084
2085static bool gpiod_free_commit(struct gpio_desc *desc)
2086{
2087 bool ret = false;
2088 unsigned long flags;
2089 struct gpio_chip *gc;
2090
2091 might_sleep();
2092
2093 gpiod_unexport(desc);
2094
2095 spin_lock_irqsave(&gpio_lock, flags);
2096
2097 gc = desc->gdev->chip;
2098 if (gc && test_bit(FLAG_REQUESTED, &desc->flags)) {
2099 if (gc->free) {
2100 spin_unlock_irqrestore(&gpio_lock, flags);
2101 might_sleep_if(gc->can_sleep);
2102 gc->free(gc, gpio_chip_hwgpio(desc));
2103 spin_lock_irqsave(&gpio_lock, flags);
2104 }
2105 kfree_const(desc->label);
2106 desc_set_label(desc, NULL);
2107 clear_bit(FLAG_ACTIVE_LOW, &desc->flags);
2108 clear_bit(FLAG_REQUESTED, &desc->flags);
2109 clear_bit(FLAG_OPEN_DRAIN, &desc->flags);
2110 clear_bit(FLAG_OPEN_SOURCE, &desc->flags);
2111 clear_bit(FLAG_PULL_UP, &desc->flags);
2112 clear_bit(FLAG_PULL_DOWN, &desc->flags);
2113 clear_bit(FLAG_BIAS_DISABLE, &desc->flags);
2114 clear_bit(FLAG_EDGE_RISING, &desc->flags);
2115 clear_bit(FLAG_EDGE_FALLING, &desc->flags);
2116 clear_bit(FLAG_IS_HOGGED, &desc->flags);
2117#ifdef CONFIG_OF_DYNAMIC
2118 desc->hog = NULL;
2119#endif
2120#ifdef CONFIG_GPIO_CDEV
2121 WRITE_ONCE(desc->debounce_period_us, 0);
2122#endif
2123 ret = true;
2124 }
2125
2126 spin_unlock_irqrestore(&gpio_lock, flags);
2127 blocking_notifier_call_chain(&desc->gdev->notifier,
2128 GPIOLINE_CHANGED_RELEASED, desc);
2129
2130 return ret;
2131}
2132
2133void gpiod_free(struct gpio_desc *desc)
2134{
2135 if (desc && desc->gdev && gpiod_free_commit(desc)) {
2136 module_put(desc->gdev->owner);
2137 put_device(&desc->gdev->dev);
2138 } else {
2139 WARN_ON(extra_checks);
2140 }
2141}
2142
2143/**
2144 * gpiochip_is_requested - return string iff signal was requested
2145 * @gc: controller managing the signal
2146 * @offset: of signal within controller's 0..(ngpio - 1) range
2147 *
2148 * Returns NULL if the GPIO is not currently requested, else a string.
2149 * The string returned is the label passed to gpio_request(); if none has been
2150 * passed it is a meaningless, non-NULL constant.
2151 *
2152 * This function is for use by GPIO controller drivers. The label can
2153 * help with diagnostics, and knowing that the signal is used as a GPIO
2154 * can help avoid accidentally multiplexing it to another controller.
2155 */
2156const char *gpiochip_is_requested(struct gpio_chip *gc, unsigned int offset)
2157{
2158 struct gpio_desc *desc;
2159
2160 desc = gpiochip_get_desc(gc, offset);
2161 if (IS_ERR(desc))
2162 return NULL;
2163
2164 if (test_bit(FLAG_REQUESTED, &desc->flags) == 0)
2165 return NULL;
2166 return desc->label;
2167}
2168EXPORT_SYMBOL_GPL(gpiochip_is_requested);
2169
2170/**
2171 * gpiochip_request_own_desc - Allow GPIO chip to request its own descriptor
2172 * @gc: GPIO chip
2173 * @hwnum: hardware number of the GPIO for which to request the descriptor
2174 * @label: label for the GPIO
2175 * @lflags: lookup flags for this GPIO or 0 if default, this can be used to
2176 * specify things like line inversion semantics with the machine flags
2177 * such as GPIO_OUT_LOW
2178 * @dflags: descriptor request flags for this GPIO or 0 if default, this
2179 * can be used to specify consumer semantics such as open drain
2180 *
2181 * Function allows GPIO chip drivers to request and use their own GPIO
2182 * descriptors via gpiolib API. Difference to gpiod_request() is that this
2183 * function will not increase reference count of the GPIO chip module. This
2184 * allows the GPIO chip module to be unloaded as needed (we assume that the
2185 * GPIO chip driver handles freeing the GPIOs it has requested).
2186 *
2187 * Returns:
2188 * A pointer to the GPIO descriptor, or an ERR_PTR()-encoded negative error
2189 * code on failure.
2190 */
2191struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *gc,
2192 unsigned int hwnum,
2193 const char *label,
2194 enum gpio_lookup_flags lflags,
2195 enum gpiod_flags dflags)
2196{
2197 struct gpio_desc *desc = gpiochip_get_desc(gc, hwnum);
2198 int ret;
2199
2200 if (IS_ERR(desc)) {
2201 chip_err(gc, "failed to get GPIO descriptor\n");
2202 return desc;
2203 }
2204
2205 ret = gpiod_request_commit(desc, label);
2206 if (ret < 0)
2207 return ERR_PTR(ret);
2208
2209 ret = gpiod_configure_flags(desc, label, lflags, dflags);
2210 if (ret) {
2211 chip_err(gc, "setup of own GPIO %s failed\n", label);
2212 gpiod_free_commit(desc);
2213 return ERR_PTR(ret);
2214 }
2215
2216 return desc;
2217}
2218EXPORT_SYMBOL_GPL(gpiochip_request_own_desc);
2219
2220/**
2221 * gpiochip_free_own_desc - Free GPIO requested by the chip driver
2222 * @desc: GPIO descriptor to free
2223 *
2224 * Function frees the given GPIO requested previously with
2225 * gpiochip_request_own_desc().
2226 */
2227void gpiochip_free_own_desc(struct gpio_desc *desc)
2228{
2229 if (desc)
2230 gpiod_free_commit(desc);
2231}
2232EXPORT_SYMBOL_GPL(gpiochip_free_own_desc);
2233
2234/*
2235 * Drivers MUST set GPIO direction before making get/set calls. In
2236 * some cases this is done in early boot, before IRQs are enabled.
2237 *
2238 * As a rule these aren't called more than once (except for drivers
2239 * using the open-drain emulation idiom) so these are natural places
2240 * to accumulate extra debugging checks. Note that we can't (yet)
2241 * rely on gpio_request() having been called beforehand.
2242 */
2243
2244static int gpio_do_set_config(struct gpio_chip *gc, unsigned int offset,
2245 unsigned long config)
2246{
2247 if (!gc->set_config)
2248 return -ENOTSUPP;
2249
2250 return gc->set_config(gc, offset, config);
2251}
2252
2253static int gpio_set_config_with_argument(struct gpio_desc *desc,
2254 enum pin_config_param mode,
2255 u32 argument)
2256{
2257 struct gpio_chip *gc = desc->gdev->chip;
2258 unsigned long config;
2259
2260 config = pinconf_to_config_packed(mode, argument);
2261 return gpio_do_set_config(gc, gpio_chip_hwgpio(desc), config);
2262}
2263
2264static int gpio_set_config_with_argument_optional(struct gpio_desc *desc,
2265 enum pin_config_param mode,
2266 u32 argument)
2267{
2268 struct device *dev = &desc->gdev->dev;
2269 int gpio = gpio_chip_hwgpio(desc);
2270 int ret;
2271
2272 ret = gpio_set_config_with_argument(desc, mode, argument);
2273 if (ret != -ENOTSUPP)
2274 return ret;
2275
2276 switch (mode) {
2277 case PIN_CONFIG_PERSIST_STATE:
2278 dev_dbg(dev, "Persistence not supported for GPIO %d\n", gpio);
2279 break;
2280 default:
2281 break;
2282 }
2283
2284 return 0;
2285}
2286
2287static int gpio_set_config(struct gpio_desc *desc, enum pin_config_param mode)
2288{
2289 return gpio_set_config_with_argument(desc, mode, 0);
2290}
2291
2292static int gpio_set_bias(struct gpio_desc *desc)
2293{
2294 enum pin_config_param bias;
2295 unsigned int arg;
2296
2297 if (test_bit(FLAG_BIAS_DISABLE, &desc->flags))
2298 bias = PIN_CONFIG_BIAS_DISABLE;
2299 else if (test_bit(FLAG_PULL_UP, &desc->flags))
2300 bias = PIN_CONFIG_BIAS_PULL_UP;
2301 else if (test_bit(FLAG_PULL_DOWN, &desc->flags))
2302 bias = PIN_CONFIG_BIAS_PULL_DOWN;
2303 else
2304 return 0;
2305
2306 switch (bias) {
2307 case PIN_CONFIG_BIAS_PULL_DOWN:
2308 case PIN_CONFIG_BIAS_PULL_UP:
2309 arg = 1;
2310 break;
2311
2312 default:
2313 arg = 0;
2314 break;
2315 }
2316
2317 return gpio_set_config_with_argument_optional(desc, bias, arg);
2318}
2319
2320/**
2321 * gpio_set_debounce_timeout() - Set debounce timeout
2322 * @desc: GPIO descriptor to set the debounce timeout
2323 * @debounce: Debounce timeout in microseconds
2324 *
2325 * The function calls the certain GPIO driver to set debounce timeout
2326 * in the hardware.
2327 *
2328 * Returns 0 on success, or negative error code otherwise.
2329 */
2330int gpio_set_debounce_timeout(struct gpio_desc *desc, unsigned int debounce)
2331{
2332 return gpio_set_config_with_argument_optional(desc,
2333 PIN_CONFIG_INPUT_DEBOUNCE,
2334 debounce);
2335}
2336
2337/**
2338 * gpiod_direction_input - set the GPIO direction to input
2339 * @desc: GPIO to set to input
2340 *
2341 * Set the direction of the passed GPIO to input, such as gpiod_get_value() can
2342 * be called safely on it.
2343 *
2344 * Return 0 in case of success, else an error code.
2345 */
2346int gpiod_direction_input(struct gpio_desc *desc)
2347{
2348 struct gpio_chip *gc;
2349 int ret = 0;
2350
2351 VALIDATE_DESC(desc);
2352 gc = desc->gdev->chip;
2353
2354 /*
2355 * It is legal to have no .get() and .direction_input() specified if
2356 * the chip is output-only, but you can't specify .direction_input()
2357 * and not support the .get() operation, that doesn't make sense.
2358 */
2359 if (!gc->get && gc->direction_input) {
2360 gpiod_warn(desc,
2361 "%s: missing get() but have direction_input()\n",
2362 __func__);
2363 return -EIO;
2364 }
2365
2366 /*
2367 * If we have a .direction_input() callback, things are simple,
2368 * just call it. Else we are some input-only chip so try to check the
2369 * direction (if .get_direction() is supported) else we silently
2370 * assume we are in input mode after this.
2371 */
2372 if (gc->direction_input) {
2373 ret = gc->direction_input(gc, gpio_chip_hwgpio(desc));
2374 } else if (gc->get_direction &&
2375 (gc->get_direction(gc, gpio_chip_hwgpio(desc)) != 1)) {
2376 gpiod_warn(desc,
2377 "%s: missing direction_input() operation and line is output\n",
2378 __func__);
2379 return -EIO;
2380 }
2381 if (ret == 0) {
2382 clear_bit(FLAG_IS_OUT, &desc->flags);
2383 ret = gpio_set_bias(desc);
2384 }
2385
2386 trace_gpio_direction(desc_to_gpio(desc), 1, ret);
2387
2388 return ret;
2389}
2390EXPORT_SYMBOL_GPL(gpiod_direction_input);
2391
2392static int gpiod_direction_output_raw_commit(struct gpio_desc *desc, int value)
2393{
2394 struct gpio_chip *gc = desc->gdev->chip;
2395 int val = !!value;
2396 int ret = 0;
2397
2398 /*
2399 * It's OK not to specify .direction_output() if the gpiochip is
2400 * output-only, but if there is then not even a .set() operation it
2401 * is pretty tricky to drive the output line.
2402 */
2403 if (!gc->set && !gc->direction_output) {
2404 gpiod_warn(desc,
2405 "%s: missing set() and direction_output() operations\n",
2406 __func__);
2407 return -EIO;
2408 }
2409
2410 if (gc->direction_output) {
2411 ret = gc->direction_output(gc, gpio_chip_hwgpio(desc), val);
2412 } else {
2413 /* Check that we are in output mode if we can */
2414 if (gc->get_direction &&
2415 gc->get_direction(gc, gpio_chip_hwgpio(desc))) {
2416 gpiod_warn(desc,
2417 "%s: missing direction_output() operation\n",
2418 __func__);
2419 return -EIO;
2420 }
2421 /*
2422 * If we can't actively set the direction, we are some
2423 * output-only chip, so just drive the output as desired.
2424 */
2425 gc->set(gc, gpio_chip_hwgpio(desc), val);
2426 }
2427
2428 if (!ret)
2429 set_bit(FLAG_IS_OUT, &desc->flags);
2430 trace_gpio_value(desc_to_gpio(desc), 0, val);
2431 trace_gpio_direction(desc_to_gpio(desc), 0, ret);
2432 return ret;
2433}
2434
2435/**
2436 * gpiod_direction_output_raw - set the GPIO direction to output
2437 * @desc: GPIO to set to output
2438 * @value: initial output value of the GPIO
2439 *
2440 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
2441 * be called safely on it. The initial value of the output must be specified
2442 * as raw value on the physical line without regard for the ACTIVE_LOW status.
2443 *
2444 * Return 0 in case of success, else an error code.
2445 */
2446int gpiod_direction_output_raw(struct gpio_desc *desc, int value)
2447{
2448 VALIDATE_DESC(desc);
2449 return gpiod_direction_output_raw_commit(desc, value);
2450}
2451EXPORT_SYMBOL_GPL(gpiod_direction_output_raw);
2452
2453/**
2454 * gpiod_direction_output - set the GPIO direction to output
2455 * @desc: GPIO to set to output
2456 * @value: initial output value of the GPIO
2457 *
2458 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
2459 * be called safely on it. The initial value of the output must be specified
2460 * as the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
2461 * account.
2462 *
2463 * Return 0 in case of success, else an error code.
2464 */
2465int gpiod_direction_output(struct gpio_desc *desc, int value)
2466{
2467 int ret;
2468
2469 VALIDATE_DESC(desc);
2470 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
2471 value = !value;
2472 else
2473 value = !!value;
2474
2475 /* GPIOs used for enabled IRQs shall not be set as output */
2476 if (test_bit(FLAG_USED_AS_IRQ, &desc->flags) &&
2477 test_bit(FLAG_IRQ_IS_ENABLED, &desc->flags)) {
2478 gpiod_err(desc,
2479 "%s: tried to set a GPIO tied to an IRQ as output\n",
2480 __func__);
2481 return -EIO;
2482 }
2483
2484 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) {
2485 /* First see if we can enable open drain in hardware */
2486 ret = gpio_set_config(desc, PIN_CONFIG_DRIVE_OPEN_DRAIN);
2487 if (!ret)
2488 goto set_output_value;
2489 /* Emulate open drain by not actively driving the line high */
2490 if (value) {
2491 ret = gpiod_direction_input(desc);
2492 goto set_output_flag;
2493 }
2494 } else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) {
2495 ret = gpio_set_config(desc, PIN_CONFIG_DRIVE_OPEN_SOURCE);
2496 if (!ret)
2497 goto set_output_value;
2498 /* Emulate open source by not actively driving the line low */
2499 if (!value) {
2500 ret = gpiod_direction_input(desc);
2501 goto set_output_flag;
2502 }
2503 } else {
2504 gpio_set_config(desc, PIN_CONFIG_DRIVE_PUSH_PULL);
2505 }
2506
2507set_output_value:
2508 ret = gpio_set_bias(desc);
2509 if (ret)
2510 return ret;
2511 return gpiod_direction_output_raw_commit(desc, value);
2512
2513set_output_flag:
2514 /*
2515 * When emulating open-source or open-drain functionalities by not
2516 * actively driving the line (setting mode to input) we still need to
2517 * set the IS_OUT flag or otherwise we won't be able to set the line
2518 * value anymore.
2519 */
2520 if (ret == 0)
2521 set_bit(FLAG_IS_OUT, &desc->flags);
2522 return ret;
2523}
2524EXPORT_SYMBOL_GPL(gpiod_direction_output);
2525
2526/**
2527 * gpiod_enable_hw_timestamp_ns - Enable hardware timestamp in nanoseconds.
2528 *
2529 * @desc: GPIO to enable.
2530 * @flags: Flags related to GPIO edge.
2531 *
2532 * Return 0 in case of success, else negative error code.
2533 */
2534int gpiod_enable_hw_timestamp_ns(struct gpio_desc *desc, unsigned long flags)
2535{
2536 int ret = 0;
2537 struct gpio_chip *gc;
2538
2539 VALIDATE_DESC(desc);
2540
2541 gc = desc->gdev->chip;
2542 if (!gc->en_hw_timestamp) {
2543 gpiod_warn(desc, "%s: hw ts not supported\n", __func__);
2544 return -ENOTSUPP;
2545 }
2546
2547 ret = gc->en_hw_timestamp(gc, gpio_chip_hwgpio(desc), flags);
2548 if (ret)
2549 gpiod_warn(desc, "%s: hw ts request failed\n", __func__);
2550
2551 return ret;
2552}
2553EXPORT_SYMBOL_GPL(gpiod_enable_hw_timestamp_ns);
2554
2555/**
2556 * gpiod_disable_hw_timestamp_ns - Disable hardware timestamp.
2557 *
2558 * @desc: GPIO to disable.
2559 * @flags: Flags related to GPIO edge, same value as used during enable call.
2560 *
2561 * Return 0 in case of success, else negative error code.
2562 */
2563int gpiod_disable_hw_timestamp_ns(struct gpio_desc *desc, unsigned long flags)
2564{
2565 int ret = 0;
2566 struct gpio_chip *gc;
2567
2568 VALIDATE_DESC(desc);
2569
2570 gc = desc->gdev->chip;
2571 if (!gc->dis_hw_timestamp) {
2572 gpiod_warn(desc, "%s: hw ts not supported\n", __func__);
2573 return -ENOTSUPP;
2574 }
2575
2576 ret = gc->dis_hw_timestamp(gc, gpio_chip_hwgpio(desc), flags);
2577 if (ret)
2578 gpiod_warn(desc, "%s: hw ts release failed\n", __func__);
2579
2580 return ret;
2581}
2582EXPORT_SYMBOL_GPL(gpiod_disable_hw_timestamp_ns);
2583
2584/**
2585 * gpiod_set_config - sets @config for a GPIO
2586 * @desc: descriptor of the GPIO for which to set the configuration
2587 * @config: Same packed config format as generic pinconf
2588 *
2589 * Returns:
2590 * 0 on success, %-ENOTSUPP if the controller doesn't support setting the
2591 * configuration.
2592 */
2593int gpiod_set_config(struct gpio_desc *desc, unsigned long config)
2594{
2595 struct gpio_chip *gc;
2596
2597 VALIDATE_DESC(desc);
2598 gc = desc->gdev->chip;
2599
2600 return gpio_do_set_config(gc, gpio_chip_hwgpio(desc), config);
2601}
2602EXPORT_SYMBOL_GPL(gpiod_set_config);
2603
2604/**
2605 * gpiod_set_debounce - sets @debounce time for a GPIO
2606 * @desc: descriptor of the GPIO for which to set debounce time
2607 * @debounce: debounce time in microseconds
2608 *
2609 * Returns:
2610 * 0 on success, %-ENOTSUPP if the controller doesn't support setting the
2611 * debounce time.
2612 */
2613int gpiod_set_debounce(struct gpio_desc *desc, unsigned int debounce)
2614{
2615 unsigned long config;
2616
2617 config = pinconf_to_config_packed(PIN_CONFIG_INPUT_DEBOUNCE, debounce);
2618 return gpiod_set_config(desc, config);
2619}
2620EXPORT_SYMBOL_GPL(gpiod_set_debounce);
2621
2622/**
2623 * gpiod_set_transitory - Lose or retain GPIO state on suspend or reset
2624 * @desc: descriptor of the GPIO for which to configure persistence
2625 * @transitory: True to lose state on suspend or reset, false for persistence
2626 *
2627 * Returns:
2628 * 0 on success, otherwise a negative error code.
2629 */
2630int gpiod_set_transitory(struct gpio_desc *desc, bool transitory)
2631{
2632 VALIDATE_DESC(desc);
2633 /*
2634 * Handle FLAG_TRANSITORY first, enabling queries to gpiolib for
2635 * persistence state.
2636 */
2637 assign_bit(FLAG_TRANSITORY, &desc->flags, transitory);
2638
2639 /* If the driver supports it, set the persistence state now */
2640 return gpio_set_config_with_argument_optional(desc,
2641 PIN_CONFIG_PERSIST_STATE,
2642 !transitory);
2643}
2644EXPORT_SYMBOL_GPL(gpiod_set_transitory);
2645
2646/**
2647 * gpiod_is_active_low - test whether a GPIO is active-low or not
2648 * @desc: the gpio descriptor to test
2649 *
2650 * Returns 1 if the GPIO is active-low, 0 otherwise.
2651 */
2652int gpiod_is_active_low(const struct gpio_desc *desc)
2653{
2654 VALIDATE_DESC(desc);
2655 return test_bit(FLAG_ACTIVE_LOW, &desc->flags);
2656}
2657EXPORT_SYMBOL_GPL(gpiod_is_active_low);
2658
2659/**
2660 * gpiod_toggle_active_low - toggle whether a GPIO is active-low or not
2661 * @desc: the gpio descriptor to change
2662 */
2663void gpiod_toggle_active_low(struct gpio_desc *desc)
2664{
2665 VALIDATE_DESC_VOID(desc);
2666 change_bit(FLAG_ACTIVE_LOW, &desc->flags);
2667}
2668EXPORT_SYMBOL_GPL(gpiod_toggle_active_low);
2669
2670static int gpio_chip_get_value(struct gpio_chip *gc, const struct gpio_desc *desc)
2671{
2672 return gc->get ? gc->get(gc, gpio_chip_hwgpio(desc)) : -EIO;
2673}
2674
2675/* I/O calls are only valid after configuration completed; the relevant
2676 * "is this a valid GPIO" error checks should already have been done.
2677 *
2678 * "Get" operations are often inlinable as reading a pin value register,
2679 * and masking the relevant bit in that register.
2680 *
2681 * When "set" operations are inlinable, they involve writing that mask to
2682 * one register to set a low value, or a different register to set it high.
2683 * Otherwise locking is needed, so there may be little value to inlining.
2684 *
2685 *------------------------------------------------------------------------
2686 *
2687 * IMPORTANT!!! The hot paths -- get/set value -- assume that callers
2688 * have requested the GPIO. That can include implicit requesting by
2689 * a direction setting call. Marking a gpio as requested locks its chip
2690 * in memory, guaranteeing that these table lookups need no more locking
2691 * and that gpiochip_remove() will fail.
2692 *
2693 * REVISIT when debugging, consider adding some instrumentation to ensure
2694 * that the GPIO was actually requested.
2695 */
2696
2697static int gpiod_get_raw_value_commit(const struct gpio_desc *desc)
2698{
2699 struct gpio_chip *gc;
2700 int value;
2701
2702 gc = desc->gdev->chip;
2703 value = gpio_chip_get_value(gc, desc);
2704 value = value < 0 ? value : !!value;
2705 trace_gpio_value(desc_to_gpio(desc), 1, value);
2706 return value;
2707}
2708
2709static int gpio_chip_get_multiple(struct gpio_chip *gc,
2710 unsigned long *mask, unsigned long *bits)
2711{
2712 if (gc->get_multiple)
2713 return gc->get_multiple(gc, mask, bits);
2714 if (gc->get) {
2715 int i, value;
2716
2717 for_each_set_bit(i, mask, gc->ngpio) {
2718 value = gc->get(gc, i);
2719 if (value < 0)
2720 return value;
2721 __assign_bit(i, bits, value);
2722 }
2723 return 0;
2724 }
2725 return -EIO;
2726}
2727
2728int gpiod_get_array_value_complex(bool raw, bool can_sleep,
2729 unsigned int array_size,
2730 struct gpio_desc **desc_array,
2731 struct gpio_array *array_info,
2732 unsigned long *value_bitmap)
2733{
2734 int ret, i = 0;
2735
2736 /*
2737 * Validate array_info against desc_array and its size.
2738 * It should immediately follow desc_array if both
2739 * have been obtained from the same gpiod_get_array() call.
2740 */
2741 if (array_info && array_info->desc == desc_array &&
2742 array_size <= array_info->size &&
2743 (void *)array_info == desc_array + array_info->size) {
2744 if (!can_sleep)
2745 WARN_ON(array_info->chip->can_sleep);
2746
2747 ret = gpio_chip_get_multiple(array_info->chip,
2748 array_info->get_mask,
2749 value_bitmap);
2750 if (ret)
2751 return ret;
2752
2753 if (!raw && !bitmap_empty(array_info->invert_mask, array_size))
2754 bitmap_xor(value_bitmap, value_bitmap,
2755 array_info->invert_mask, array_size);
2756
2757 i = find_first_zero_bit(array_info->get_mask, array_size);
2758 if (i == array_size)
2759 return 0;
2760 } else {
2761 array_info = NULL;
2762 }
2763
2764 while (i < array_size) {
2765 struct gpio_chip *gc = desc_array[i]->gdev->chip;
2766 DECLARE_BITMAP(fastpath_mask, FASTPATH_NGPIO);
2767 DECLARE_BITMAP(fastpath_bits, FASTPATH_NGPIO);
2768 unsigned long *mask, *bits;
2769 int first, j;
2770
2771 if (likely(gc->ngpio <= FASTPATH_NGPIO)) {
2772 mask = fastpath_mask;
2773 bits = fastpath_bits;
2774 } else {
2775 gfp_t flags = can_sleep ? GFP_KERNEL : GFP_ATOMIC;
2776
2777 mask = bitmap_alloc(gc->ngpio, flags);
2778 if (!mask)
2779 return -ENOMEM;
2780
2781 bits = bitmap_alloc(gc->ngpio, flags);
2782 if (!bits) {
2783 bitmap_free(mask);
2784 return -ENOMEM;
2785 }
2786 }
2787
2788 bitmap_zero(mask, gc->ngpio);
2789
2790 if (!can_sleep)
2791 WARN_ON(gc->can_sleep);
2792
2793 /* collect all inputs belonging to the same chip */
2794 first = i;
2795 do {
2796 const struct gpio_desc *desc = desc_array[i];
2797 int hwgpio = gpio_chip_hwgpio(desc);
2798
2799 __set_bit(hwgpio, mask);
2800 i++;
2801
2802 if (array_info)
2803 i = find_next_zero_bit(array_info->get_mask,
2804 array_size, i);
2805 } while ((i < array_size) &&
2806 (desc_array[i]->gdev->chip == gc));
2807
2808 ret = gpio_chip_get_multiple(gc, mask, bits);
2809 if (ret) {
2810 if (mask != fastpath_mask)
2811 bitmap_free(mask);
2812 if (bits != fastpath_bits)
2813 bitmap_free(bits);
2814 return ret;
2815 }
2816
2817 for (j = first; j < i; ) {
2818 const struct gpio_desc *desc = desc_array[j];
2819 int hwgpio = gpio_chip_hwgpio(desc);
2820 int value = test_bit(hwgpio, bits);
2821
2822 if (!raw && test_bit(FLAG_ACTIVE_LOW, &desc->flags))
2823 value = !value;
2824 __assign_bit(j, value_bitmap, value);
2825 trace_gpio_value(desc_to_gpio(desc), 1, value);
2826 j++;
2827
2828 if (array_info)
2829 j = find_next_zero_bit(array_info->get_mask, i,
2830 j);
2831 }
2832
2833 if (mask != fastpath_mask)
2834 bitmap_free(mask);
2835 if (bits != fastpath_bits)
2836 bitmap_free(bits);
2837 }
2838 return 0;
2839}
2840
2841/**
2842 * gpiod_get_raw_value() - return a gpio's raw value
2843 * @desc: gpio whose value will be returned
2844 *
2845 * Return the GPIO's raw value, i.e. the value of the physical line disregarding
2846 * its ACTIVE_LOW status, or negative errno on failure.
2847 *
2848 * This function can be called from contexts where we cannot sleep, and will
2849 * complain if the GPIO chip functions potentially sleep.
2850 */
2851int gpiod_get_raw_value(const struct gpio_desc *desc)
2852{
2853 VALIDATE_DESC(desc);
2854 /* Should be using gpiod_get_raw_value_cansleep() */
2855 WARN_ON(desc->gdev->chip->can_sleep);
2856 return gpiod_get_raw_value_commit(desc);
2857}
2858EXPORT_SYMBOL_GPL(gpiod_get_raw_value);
2859
2860/**
2861 * gpiod_get_value() - return a gpio's value
2862 * @desc: gpio whose value will be returned
2863 *
2864 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
2865 * account, or negative errno on failure.
2866 *
2867 * This function can be called from contexts where we cannot sleep, and will
2868 * complain if the GPIO chip functions potentially sleep.
2869 */
2870int gpiod_get_value(const struct gpio_desc *desc)
2871{
2872 int value;
2873
2874 VALIDATE_DESC(desc);
2875 /* Should be using gpiod_get_value_cansleep() */
2876 WARN_ON(desc->gdev->chip->can_sleep);
2877
2878 value = gpiod_get_raw_value_commit(desc);
2879 if (value < 0)
2880 return value;
2881
2882 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
2883 value = !value;
2884
2885 return value;
2886}
2887EXPORT_SYMBOL_GPL(gpiod_get_value);
2888
2889/**
2890 * gpiod_get_raw_array_value() - read raw values from an array of GPIOs
2891 * @array_size: number of elements in the descriptor array / value bitmap
2892 * @desc_array: array of GPIO descriptors whose values will be read
2893 * @array_info: information on applicability of fast bitmap processing path
2894 * @value_bitmap: bitmap to store the read values
2895 *
2896 * Read the raw values of the GPIOs, i.e. the values of the physical lines
2897 * without regard for their ACTIVE_LOW status. Return 0 in case of success,
2898 * else an error code.
2899 *
2900 * This function can be called from contexts where we cannot sleep,
2901 * and it will complain if the GPIO chip functions potentially sleep.
2902 */
2903int gpiod_get_raw_array_value(unsigned int array_size,
2904 struct gpio_desc **desc_array,
2905 struct gpio_array *array_info,
2906 unsigned long *value_bitmap)
2907{
2908 if (!desc_array)
2909 return -EINVAL;
2910 return gpiod_get_array_value_complex(true, false, array_size,
2911 desc_array, array_info,
2912 value_bitmap);
2913}
2914EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value);
2915
2916/**
2917 * gpiod_get_array_value() - read values from an array of GPIOs
2918 * @array_size: number of elements in the descriptor array / value bitmap
2919 * @desc_array: array of GPIO descriptors whose values will be read
2920 * @array_info: information on applicability of fast bitmap processing path
2921 * @value_bitmap: bitmap to store the read values
2922 *
2923 * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
2924 * into account. Return 0 in case of success, else an error code.
2925 *
2926 * This function can be called from contexts where we cannot sleep,
2927 * and it will complain if the GPIO chip functions potentially sleep.
2928 */
2929int gpiod_get_array_value(unsigned int array_size,
2930 struct gpio_desc **desc_array,
2931 struct gpio_array *array_info,
2932 unsigned long *value_bitmap)
2933{
2934 if (!desc_array)
2935 return -EINVAL;
2936 return gpiod_get_array_value_complex(false, false, array_size,
2937 desc_array, array_info,
2938 value_bitmap);
2939}
2940EXPORT_SYMBOL_GPL(gpiod_get_array_value);
2941
2942/*
2943 * gpio_set_open_drain_value_commit() - Set the open drain gpio's value.
2944 * @desc: gpio descriptor whose state need to be set.
2945 * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
2946 */
2947static void gpio_set_open_drain_value_commit(struct gpio_desc *desc, bool value)
2948{
2949 int ret = 0;
2950 struct gpio_chip *gc = desc->gdev->chip;
2951 int offset = gpio_chip_hwgpio(desc);
2952
2953 if (value) {
2954 ret = gc->direction_input(gc, offset);
2955 } else {
2956 ret = gc->direction_output(gc, offset, 0);
2957 if (!ret)
2958 set_bit(FLAG_IS_OUT, &desc->flags);
2959 }
2960 trace_gpio_direction(desc_to_gpio(desc), value, ret);
2961 if (ret < 0)
2962 gpiod_err(desc,
2963 "%s: Error in set_value for open drain err %d\n",
2964 __func__, ret);
2965}
2966
2967/*
2968 * _gpio_set_open_source_value() - Set the open source gpio's value.
2969 * @desc: gpio descriptor whose state need to be set.
2970 * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
2971 */
2972static void gpio_set_open_source_value_commit(struct gpio_desc *desc, bool value)
2973{
2974 int ret = 0;
2975 struct gpio_chip *gc = desc->gdev->chip;
2976 int offset = gpio_chip_hwgpio(desc);
2977
2978 if (value) {
2979 ret = gc->direction_output(gc, offset, 1);
2980 if (!ret)
2981 set_bit(FLAG_IS_OUT, &desc->flags);
2982 } else {
2983 ret = gc->direction_input(gc, offset);
2984 }
2985 trace_gpio_direction(desc_to_gpio(desc), !value, ret);
2986 if (ret < 0)
2987 gpiod_err(desc,
2988 "%s: Error in set_value for open source err %d\n",
2989 __func__, ret);
2990}
2991
2992static void gpiod_set_raw_value_commit(struct gpio_desc *desc, bool value)
2993{
2994 struct gpio_chip *gc;
2995
2996 gc = desc->gdev->chip;
2997 trace_gpio_value(desc_to_gpio(desc), 0, value);
2998 gc->set(gc, gpio_chip_hwgpio(desc), value);
2999}
3000
3001/*
3002 * set multiple outputs on the same chip;
3003 * use the chip's set_multiple function if available;
3004 * otherwise set the outputs sequentially;
3005 * @chip: the GPIO chip we operate on
3006 * @mask: bit mask array; one bit per output; BITS_PER_LONG bits per word
3007 * defines which outputs are to be changed
3008 * @bits: bit value array; one bit per output; BITS_PER_LONG bits per word
3009 * defines the values the outputs specified by mask are to be set to
3010 */
3011static void gpio_chip_set_multiple(struct gpio_chip *gc,
3012 unsigned long *mask, unsigned long *bits)
3013{
3014 if (gc->set_multiple) {
3015 gc->set_multiple(gc, mask, bits);
3016 } else {
3017 unsigned int i;
3018
3019 /* set outputs if the corresponding mask bit is set */
3020 for_each_set_bit(i, mask, gc->ngpio)
3021 gc->set(gc, i, test_bit(i, bits));
3022 }
3023}
3024
3025int gpiod_set_array_value_complex(bool raw, bool can_sleep,
3026 unsigned int array_size,
3027 struct gpio_desc **desc_array,
3028 struct gpio_array *array_info,
3029 unsigned long *value_bitmap)
3030{
3031 int i = 0;
3032
3033 /*
3034 * Validate array_info against desc_array and its size.
3035 * It should immediately follow desc_array if both
3036 * have been obtained from the same gpiod_get_array() call.
3037 */
3038 if (array_info && array_info->desc == desc_array &&
3039 array_size <= array_info->size &&
3040 (void *)array_info == desc_array + array_info->size) {
3041 if (!can_sleep)
3042 WARN_ON(array_info->chip->can_sleep);
3043
3044 if (!raw && !bitmap_empty(array_info->invert_mask, array_size))
3045 bitmap_xor(value_bitmap, value_bitmap,
3046 array_info->invert_mask, array_size);
3047
3048 gpio_chip_set_multiple(array_info->chip, array_info->set_mask,
3049 value_bitmap);
3050
3051 i = find_first_zero_bit(array_info->set_mask, array_size);
3052 if (i == array_size)
3053 return 0;
3054 } else {
3055 array_info = NULL;
3056 }
3057
3058 while (i < array_size) {
3059 struct gpio_chip *gc = desc_array[i]->gdev->chip;
3060 DECLARE_BITMAP(fastpath_mask, FASTPATH_NGPIO);
3061 DECLARE_BITMAP(fastpath_bits, FASTPATH_NGPIO);
3062 unsigned long *mask, *bits;
3063 int count = 0;
3064
3065 if (likely(gc->ngpio <= FASTPATH_NGPIO)) {
3066 mask = fastpath_mask;
3067 bits = fastpath_bits;
3068 } else {
3069 gfp_t flags = can_sleep ? GFP_KERNEL : GFP_ATOMIC;
3070
3071 mask = bitmap_alloc(gc->ngpio, flags);
3072 if (!mask)
3073 return -ENOMEM;
3074
3075 bits = bitmap_alloc(gc->ngpio, flags);
3076 if (!bits) {
3077 bitmap_free(mask);
3078 return -ENOMEM;
3079 }
3080 }
3081
3082 bitmap_zero(mask, gc->ngpio);
3083
3084 if (!can_sleep)
3085 WARN_ON(gc->can_sleep);
3086
3087 do {
3088 struct gpio_desc *desc = desc_array[i];
3089 int hwgpio = gpio_chip_hwgpio(desc);
3090 int value = test_bit(i, value_bitmap);
3091
3092 /*
3093 * Pins applicable for fast input but not for
3094 * fast output processing may have been already
3095 * inverted inside the fast path, skip them.
3096 */
3097 if (!raw && !(array_info &&
3098 test_bit(i, array_info->invert_mask)) &&
3099 test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3100 value = !value;
3101 trace_gpio_value(desc_to_gpio(desc), 0, value);
3102 /*
3103 * collect all normal outputs belonging to the same chip
3104 * open drain and open source outputs are set individually
3105 */
3106 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags) && !raw) {
3107 gpio_set_open_drain_value_commit(desc, value);
3108 } else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags) && !raw) {
3109 gpio_set_open_source_value_commit(desc, value);
3110 } else {
3111 __set_bit(hwgpio, mask);
3112 __assign_bit(hwgpio, bits, value);
3113 count++;
3114 }
3115 i++;
3116
3117 if (array_info)
3118 i = find_next_zero_bit(array_info->set_mask,
3119 array_size, i);
3120 } while ((i < array_size) &&
3121 (desc_array[i]->gdev->chip == gc));
3122 /* push collected bits to outputs */
3123 if (count != 0)
3124 gpio_chip_set_multiple(gc, mask, bits);
3125
3126 if (mask != fastpath_mask)
3127 bitmap_free(mask);
3128 if (bits != fastpath_bits)
3129 bitmap_free(bits);
3130 }
3131 return 0;
3132}
3133
3134/**
3135 * gpiod_set_raw_value() - assign a gpio's raw value
3136 * @desc: gpio whose value will be assigned
3137 * @value: value to assign
3138 *
3139 * Set the raw value of the GPIO, i.e. the value of its physical line without
3140 * regard for its ACTIVE_LOW status.
3141 *
3142 * This function can be called from contexts where we cannot sleep, and will
3143 * complain if the GPIO chip functions potentially sleep.
3144 */
3145void gpiod_set_raw_value(struct gpio_desc *desc, int value)
3146{
3147 VALIDATE_DESC_VOID(desc);
3148 /* Should be using gpiod_set_raw_value_cansleep() */
3149 WARN_ON(desc->gdev->chip->can_sleep);
3150 gpiod_set_raw_value_commit(desc, value);
3151}
3152EXPORT_SYMBOL_GPL(gpiod_set_raw_value);
3153
3154/**
3155 * gpiod_set_value_nocheck() - set a GPIO line value without checking
3156 * @desc: the descriptor to set the value on
3157 * @value: value to set
3158 *
3159 * This sets the value of a GPIO line backing a descriptor, applying
3160 * different semantic quirks like active low and open drain/source
3161 * handling.
3162 */
3163static void gpiod_set_value_nocheck(struct gpio_desc *desc, int value)
3164{
3165 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3166 value = !value;
3167 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags))
3168 gpio_set_open_drain_value_commit(desc, value);
3169 else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags))
3170 gpio_set_open_source_value_commit(desc, value);
3171 else
3172 gpiod_set_raw_value_commit(desc, value);
3173}
3174
3175/**
3176 * gpiod_set_value() - assign a gpio's value
3177 * @desc: gpio whose value will be assigned
3178 * @value: value to assign
3179 *
3180 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW,
3181 * OPEN_DRAIN and OPEN_SOURCE flags into account.
3182 *
3183 * This function can be called from contexts where we cannot sleep, and will
3184 * complain if the GPIO chip functions potentially sleep.
3185 */
3186void gpiod_set_value(struct gpio_desc *desc, int value)
3187{
3188 VALIDATE_DESC_VOID(desc);
3189 /* Should be using gpiod_set_value_cansleep() */
3190 WARN_ON(desc->gdev->chip->can_sleep);
3191 gpiod_set_value_nocheck(desc, value);
3192}
3193EXPORT_SYMBOL_GPL(gpiod_set_value);
3194
3195/**
3196 * gpiod_set_raw_array_value() - assign values to an array of GPIOs
3197 * @array_size: number of elements in the descriptor array / value bitmap
3198 * @desc_array: array of GPIO descriptors whose values will be assigned
3199 * @array_info: information on applicability of fast bitmap processing path
3200 * @value_bitmap: bitmap of values to assign
3201 *
3202 * Set the raw values of the GPIOs, i.e. the values of the physical lines
3203 * without regard for their ACTIVE_LOW status.
3204 *
3205 * This function can be called from contexts where we cannot sleep, and will
3206 * complain if the GPIO chip functions potentially sleep.
3207 */
3208int gpiod_set_raw_array_value(unsigned int array_size,
3209 struct gpio_desc **desc_array,
3210 struct gpio_array *array_info,
3211 unsigned long *value_bitmap)
3212{
3213 if (!desc_array)
3214 return -EINVAL;
3215 return gpiod_set_array_value_complex(true, false, array_size,
3216 desc_array, array_info, value_bitmap);
3217}
3218EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value);
3219
3220/**
3221 * gpiod_set_array_value() - assign values to an array of GPIOs
3222 * @array_size: number of elements in the descriptor array / value bitmap
3223 * @desc_array: array of GPIO descriptors whose values will be assigned
3224 * @array_info: information on applicability of fast bitmap processing path
3225 * @value_bitmap: bitmap of values to assign
3226 *
3227 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3228 * into account.
3229 *
3230 * This function can be called from contexts where we cannot sleep, and will
3231 * complain if the GPIO chip functions potentially sleep.
3232 */
3233int gpiod_set_array_value(unsigned int array_size,
3234 struct gpio_desc **desc_array,
3235 struct gpio_array *array_info,
3236 unsigned long *value_bitmap)
3237{
3238 if (!desc_array)
3239 return -EINVAL;
3240 return gpiod_set_array_value_complex(false, false, array_size,
3241 desc_array, array_info,
3242 value_bitmap);
3243}
3244EXPORT_SYMBOL_GPL(gpiod_set_array_value);
3245
3246/**
3247 * gpiod_cansleep() - report whether gpio value access may sleep
3248 * @desc: gpio to check
3249 *
3250 */
3251int gpiod_cansleep(const struct gpio_desc *desc)
3252{
3253 VALIDATE_DESC(desc);
3254 return desc->gdev->chip->can_sleep;
3255}
3256EXPORT_SYMBOL_GPL(gpiod_cansleep);
3257
3258/**
3259 * gpiod_set_consumer_name() - set the consumer name for the descriptor
3260 * @desc: gpio to set the consumer name on
3261 * @name: the new consumer name
3262 */
3263int gpiod_set_consumer_name(struct gpio_desc *desc, const char *name)
3264{
3265 VALIDATE_DESC(desc);
3266 if (name) {
3267 name = kstrdup_const(name, GFP_KERNEL);
3268 if (!name)
3269 return -ENOMEM;
3270 }
3271
3272 kfree_const(desc->label);
3273 desc_set_label(desc, name);
3274
3275 return 0;
3276}
3277EXPORT_SYMBOL_GPL(gpiod_set_consumer_name);
3278
3279/**
3280 * gpiod_to_irq() - return the IRQ corresponding to a GPIO
3281 * @desc: gpio whose IRQ will be returned (already requested)
3282 *
3283 * Return the IRQ corresponding to the passed GPIO, or an error code in case of
3284 * error.
3285 */
3286int gpiod_to_irq(const struct gpio_desc *desc)
3287{
3288 struct gpio_chip *gc;
3289 int offset;
3290
3291 /*
3292 * Cannot VALIDATE_DESC() here as gpiod_to_irq() consumer semantics
3293 * requires this function to not return zero on an invalid descriptor
3294 * but rather a negative error number.
3295 */
3296 if (!desc || IS_ERR(desc) || !desc->gdev || !desc->gdev->chip)
3297 return -EINVAL;
3298
3299 gc = desc->gdev->chip;
3300 offset = gpio_chip_hwgpio(desc);
3301 if (gc->to_irq) {
3302 int retirq = gc->to_irq(gc, offset);
3303
3304 /* Zero means NO_IRQ */
3305 if (!retirq)
3306 return -ENXIO;
3307
3308 return retirq;
3309 }
3310#ifdef CONFIG_GPIOLIB_IRQCHIP
3311 if (gc->irq.chip) {
3312 /*
3313 * Avoid race condition with other code, which tries to lookup
3314 * an IRQ before the irqchip has been properly registered,
3315 * i.e. while gpiochip is still being brought up.
3316 */
3317 return -EPROBE_DEFER;
3318 }
3319#endif
3320 return -ENXIO;
3321}
3322EXPORT_SYMBOL_GPL(gpiod_to_irq);
3323
3324/**
3325 * gpiochip_lock_as_irq() - lock a GPIO to be used as IRQ
3326 * @gc: the chip the GPIO to lock belongs to
3327 * @offset: the offset of the GPIO to lock as IRQ
3328 *
3329 * This is used directly by GPIO drivers that want to lock down
3330 * a certain GPIO line to be used for IRQs.
3331 */
3332int gpiochip_lock_as_irq(struct gpio_chip *gc, unsigned int offset)
3333{
3334 struct gpio_desc *desc;
3335
3336 desc = gpiochip_get_desc(gc, offset);
3337 if (IS_ERR(desc))
3338 return PTR_ERR(desc);
3339
3340 /*
3341 * If it's fast: flush the direction setting if something changed
3342 * behind our back
3343 */
3344 if (!gc->can_sleep && gc->get_direction) {
3345 int dir = gpiod_get_direction(desc);
3346
3347 if (dir < 0) {
3348 chip_err(gc, "%s: cannot get GPIO direction\n",
3349 __func__);
3350 return dir;
3351 }
3352 }
3353
3354 /* To be valid for IRQ the line needs to be input or open drain */
3355 if (test_bit(FLAG_IS_OUT, &desc->flags) &&
3356 !test_bit(FLAG_OPEN_DRAIN, &desc->flags)) {
3357 chip_err(gc,
3358 "%s: tried to flag a GPIO set as output for IRQ\n",
3359 __func__);
3360 return -EIO;
3361 }
3362
3363 set_bit(FLAG_USED_AS_IRQ, &desc->flags);
3364 set_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
3365
3366 /*
3367 * If the consumer has not set up a label (such as when the
3368 * IRQ is referenced from .to_irq()) we set up a label here
3369 * so it is clear this is used as an interrupt.
3370 */
3371 if (!desc->label)
3372 desc_set_label(desc, "interrupt");
3373
3374 return 0;
3375}
3376EXPORT_SYMBOL_GPL(gpiochip_lock_as_irq);
3377
3378/**
3379 * gpiochip_unlock_as_irq() - unlock a GPIO used as IRQ
3380 * @gc: the chip the GPIO to lock belongs to
3381 * @offset: the offset of the GPIO to lock as IRQ
3382 *
3383 * This is used directly by GPIO drivers that want to indicate
3384 * that a certain GPIO is no longer used exclusively for IRQ.
3385 */
3386void gpiochip_unlock_as_irq(struct gpio_chip *gc, unsigned int offset)
3387{
3388 struct gpio_desc *desc;
3389
3390 desc = gpiochip_get_desc(gc, offset);
3391 if (IS_ERR(desc))
3392 return;
3393
3394 clear_bit(FLAG_USED_AS_IRQ, &desc->flags);
3395 clear_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
3396
3397 /* If we only had this marking, erase it */
3398 if (desc->label && !strcmp(desc->label, "interrupt"))
3399 desc_set_label(desc, NULL);
3400}
3401EXPORT_SYMBOL_GPL(gpiochip_unlock_as_irq);
3402
3403void gpiochip_disable_irq(struct gpio_chip *gc, unsigned int offset)
3404{
3405 struct gpio_desc *desc = gpiochip_get_desc(gc, offset);
3406
3407 if (!IS_ERR(desc) &&
3408 !WARN_ON(!test_bit(FLAG_USED_AS_IRQ, &desc->flags)))
3409 clear_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
3410}
3411EXPORT_SYMBOL_GPL(gpiochip_disable_irq);
3412
3413void gpiochip_enable_irq(struct gpio_chip *gc, unsigned int offset)
3414{
3415 struct gpio_desc *desc = gpiochip_get_desc(gc, offset);
3416
3417 if (!IS_ERR(desc) &&
3418 !WARN_ON(!test_bit(FLAG_USED_AS_IRQ, &desc->flags))) {
3419 /*
3420 * We must not be output when using IRQ UNLESS we are
3421 * open drain.
3422 */
3423 WARN_ON(test_bit(FLAG_IS_OUT, &desc->flags) &&
3424 !test_bit(FLAG_OPEN_DRAIN, &desc->flags));
3425 set_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
3426 }
3427}
3428EXPORT_SYMBOL_GPL(gpiochip_enable_irq);
3429
3430bool gpiochip_line_is_irq(struct gpio_chip *gc, unsigned int offset)
3431{
3432 if (offset >= gc->ngpio)
3433 return false;
3434
3435 return test_bit(FLAG_USED_AS_IRQ, &gc->gpiodev->descs[offset].flags);
3436}
3437EXPORT_SYMBOL_GPL(gpiochip_line_is_irq);
3438
3439int gpiochip_reqres_irq(struct gpio_chip *gc, unsigned int offset)
3440{
3441 int ret;
3442
3443 if (!try_module_get(gc->gpiodev->owner))
3444 return -ENODEV;
3445
3446 ret = gpiochip_lock_as_irq(gc, offset);
3447 if (ret) {
3448 chip_err(gc, "unable to lock HW IRQ %u for IRQ\n", offset);
3449 module_put(gc->gpiodev->owner);
3450 return ret;
3451 }
3452 return 0;
3453}
3454EXPORT_SYMBOL_GPL(gpiochip_reqres_irq);
3455
3456void gpiochip_relres_irq(struct gpio_chip *gc, unsigned int offset)
3457{
3458 gpiochip_unlock_as_irq(gc, offset);
3459 module_put(gc->gpiodev->owner);
3460}
3461EXPORT_SYMBOL_GPL(gpiochip_relres_irq);
3462
3463bool gpiochip_line_is_open_drain(struct gpio_chip *gc, unsigned int offset)
3464{
3465 if (offset >= gc->ngpio)
3466 return false;
3467
3468 return test_bit(FLAG_OPEN_DRAIN, &gc->gpiodev->descs[offset].flags);
3469}
3470EXPORT_SYMBOL_GPL(gpiochip_line_is_open_drain);
3471
3472bool gpiochip_line_is_open_source(struct gpio_chip *gc, unsigned int offset)
3473{
3474 if (offset >= gc->ngpio)
3475 return false;
3476
3477 return test_bit(FLAG_OPEN_SOURCE, &gc->gpiodev->descs[offset].flags);
3478}
3479EXPORT_SYMBOL_GPL(gpiochip_line_is_open_source);
3480
3481bool gpiochip_line_is_persistent(struct gpio_chip *gc, unsigned int offset)
3482{
3483 if (offset >= gc->ngpio)
3484 return false;
3485
3486 return !test_bit(FLAG_TRANSITORY, &gc->gpiodev->descs[offset].flags);
3487}
3488EXPORT_SYMBOL_GPL(gpiochip_line_is_persistent);
3489
3490/**
3491 * gpiod_get_raw_value_cansleep() - return a gpio's raw value
3492 * @desc: gpio whose value will be returned
3493 *
3494 * Return the GPIO's raw value, i.e. the value of the physical line disregarding
3495 * its ACTIVE_LOW status, or negative errno on failure.
3496 *
3497 * This function is to be called from contexts that can sleep.
3498 */
3499int gpiod_get_raw_value_cansleep(const struct gpio_desc *desc)
3500{
3501 might_sleep_if(extra_checks);
3502 VALIDATE_DESC(desc);
3503 return gpiod_get_raw_value_commit(desc);
3504}
3505EXPORT_SYMBOL_GPL(gpiod_get_raw_value_cansleep);
3506
3507/**
3508 * gpiod_get_value_cansleep() - return a gpio's value
3509 * @desc: gpio whose value will be returned
3510 *
3511 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
3512 * account, or negative errno on failure.
3513 *
3514 * This function is to be called from contexts that can sleep.
3515 */
3516int gpiod_get_value_cansleep(const struct gpio_desc *desc)
3517{
3518 int value;
3519
3520 might_sleep_if(extra_checks);
3521 VALIDATE_DESC(desc);
3522 value = gpiod_get_raw_value_commit(desc);
3523 if (value < 0)
3524 return value;
3525
3526 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3527 value = !value;
3528
3529 return value;
3530}
3531EXPORT_SYMBOL_GPL(gpiod_get_value_cansleep);
3532
3533/**
3534 * gpiod_get_raw_array_value_cansleep() - read raw values from an array of GPIOs
3535 * @array_size: number of elements in the descriptor array / value bitmap
3536 * @desc_array: array of GPIO descriptors whose values will be read
3537 * @array_info: information on applicability of fast bitmap processing path
3538 * @value_bitmap: bitmap to store the read values
3539 *
3540 * Read the raw values of the GPIOs, i.e. the values of the physical lines
3541 * without regard for their ACTIVE_LOW status. Return 0 in case of success,
3542 * else an error code.
3543 *
3544 * This function is to be called from contexts that can sleep.
3545 */
3546int gpiod_get_raw_array_value_cansleep(unsigned int array_size,
3547 struct gpio_desc **desc_array,
3548 struct gpio_array *array_info,
3549 unsigned long *value_bitmap)
3550{
3551 might_sleep_if(extra_checks);
3552 if (!desc_array)
3553 return -EINVAL;
3554 return gpiod_get_array_value_complex(true, true, array_size,
3555 desc_array, array_info,
3556 value_bitmap);
3557}
3558EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value_cansleep);
3559
3560/**
3561 * gpiod_get_array_value_cansleep() - read values from an array of GPIOs
3562 * @array_size: number of elements in the descriptor array / value bitmap
3563 * @desc_array: array of GPIO descriptors whose values will be read
3564 * @array_info: information on applicability of fast bitmap processing path
3565 * @value_bitmap: bitmap to store the read values
3566 *
3567 * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3568 * into account. Return 0 in case of success, else an error code.
3569 *
3570 * This function is to be called from contexts that can sleep.
3571 */
3572int gpiod_get_array_value_cansleep(unsigned int array_size,
3573 struct gpio_desc **desc_array,
3574 struct gpio_array *array_info,
3575 unsigned long *value_bitmap)
3576{
3577 might_sleep_if(extra_checks);
3578 if (!desc_array)
3579 return -EINVAL;
3580 return gpiod_get_array_value_complex(false, true, array_size,
3581 desc_array, array_info,
3582 value_bitmap);
3583}
3584EXPORT_SYMBOL_GPL(gpiod_get_array_value_cansleep);
3585
3586/**
3587 * gpiod_set_raw_value_cansleep() - assign a gpio's raw value
3588 * @desc: gpio whose value will be assigned
3589 * @value: value to assign
3590 *
3591 * Set the raw value of the GPIO, i.e. the value of its physical line without
3592 * regard for its ACTIVE_LOW status.
3593 *
3594 * This function is to be called from contexts that can sleep.
3595 */
3596void gpiod_set_raw_value_cansleep(struct gpio_desc *desc, int value)
3597{
3598 might_sleep_if(extra_checks);
3599 VALIDATE_DESC_VOID(desc);
3600 gpiod_set_raw_value_commit(desc, value);
3601}
3602EXPORT_SYMBOL_GPL(gpiod_set_raw_value_cansleep);
3603
3604/**
3605 * gpiod_set_value_cansleep() - assign a gpio's value
3606 * @desc: gpio whose value will be assigned
3607 * @value: value to assign
3608 *
3609 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
3610 * account
3611 *
3612 * This function is to be called from contexts that can sleep.
3613 */
3614void gpiod_set_value_cansleep(struct gpio_desc *desc, int value)
3615{
3616 might_sleep_if(extra_checks);
3617 VALIDATE_DESC_VOID(desc);
3618 gpiod_set_value_nocheck(desc, value);
3619}
3620EXPORT_SYMBOL_GPL(gpiod_set_value_cansleep);
3621
3622/**
3623 * gpiod_set_raw_array_value_cansleep() - assign values to an array of GPIOs
3624 * @array_size: number of elements in the descriptor array / value bitmap
3625 * @desc_array: array of GPIO descriptors whose values will be assigned
3626 * @array_info: information on applicability of fast bitmap processing path
3627 * @value_bitmap: bitmap of values to assign
3628 *
3629 * Set the raw values of the GPIOs, i.e. the values of the physical lines
3630 * without regard for their ACTIVE_LOW status.
3631 *
3632 * This function is to be called from contexts that can sleep.
3633 */
3634int gpiod_set_raw_array_value_cansleep(unsigned int array_size,
3635 struct gpio_desc **desc_array,
3636 struct gpio_array *array_info,
3637 unsigned long *value_bitmap)
3638{
3639 might_sleep_if(extra_checks);
3640 if (!desc_array)
3641 return -EINVAL;
3642 return gpiod_set_array_value_complex(true, true, array_size, desc_array,
3643 array_info, value_bitmap);
3644}
3645EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value_cansleep);
3646
3647/**
3648 * gpiod_add_lookup_tables() - register GPIO device consumers
3649 * @tables: list of tables of consumers to register
3650 * @n: number of tables in the list
3651 */
3652void gpiod_add_lookup_tables(struct gpiod_lookup_table **tables, size_t n)
3653{
3654 unsigned int i;
3655
3656 mutex_lock(&gpio_lookup_lock);
3657
3658 for (i = 0; i < n; i++)
3659 list_add_tail(&tables[i]->list, &gpio_lookup_list);
3660
3661 mutex_unlock(&gpio_lookup_lock);
3662}
3663
3664/**
3665 * gpiod_set_array_value_cansleep() - assign values to an array of GPIOs
3666 * @array_size: number of elements in the descriptor array / value bitmap
3667 * @desc_array: array of GPIO descriptors whose values will be assigned
3668 * @array_info: information on applicability of fast bitmap processing path
3669 * @value_bitmap: bitmap of values to assign
3670 *
3671 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3672 * into account.
3673 *
3674 * This function is to be called from contexts that can sleep.
3675 */
3676int gpiod_set_array_value_cansleep(unsigned int array_size,
3677 struct gpio_desc **desc_array,
3678 struct gpio_array *array_info,
3679 unsigned long *value_bitmap)
3680{
3681 might_sleep_if(extra_checks);
3682 if (!desc_array)
3683 return -EINVAL;
3684 return gpiod_set_array_value_complex(false, true, array_size,
3685 desc_array, array_info,
3686 value_bitmap);
3687}
3688EXPORT_SYMBOL_GPL(gpiod_set_array_value_cansleep);
3689
3690/**
3691 * gpiod_add_lookup_table() - register GPIO device consumers
3692 * @table: table of consumers to register
3693 */
3694void gpiod_add_lookup_table(struct gpiod_lookup_table *table)
3695{
3696 gpiod_add_lookup_tables(&table, 1);
3697}
3698EXPORT_SYMBOL_GPL(gpiod_add_lookup_table);
3699
3700/**
3701 * gpiod_remove_lookup_table() - unregister GPIO device consumers
3702 * @table: table of consumers to unregister
3703 */
3704void gpiod_remove_lookup_table(struct gpiod_lookup_table *table)
3705{
3706 /* Nothing to remove */
3707 if (!table)
3708 return;
3709
3710 mutex_lock(&gpio_lookup_lock);
3711
3712 list_del(&table->list);
3713
3714 mutex_unlock(&gpio_lookup_lock);
3715}
3716EXPORT_SYMBOL_GPL(gpiod_remove_lookup_table);
3717
3718/**
3719 * gpiod_add_hogs() - register a set of GPIO hogs from machine code
3720 * @hogs: table of gpio hog entries with a zeroed sentinel at the end
3721 */
3722void gpiod_add_hogs(struct gpiod_hog *hogs)
3723{
3724 struct gpio_chip *gc;
3725 struct gpiod_hog *hog;
3726
3727 mutex_lock(&gpio_machine_hogs_mutex);
3728
3729 for (hog = &hogs[0]; hog->chip_label; hog++) {
3730 list_add_tail(&hog->list, &gpio_machine_hogs);
3731
3732 /*
3733 * The chip may have been registered earlier, so check if it
3734 * exists and, if so, try to hog the line now.
3735 */
3736 gc = find_chip_by_name(hog->chip_label);
3737 if (gc)
3738 gpiochip_machine_hog(gc, hog);
3739 }
3740
3741 mutex_unlock(&gpio_machine_hogs_mutex);
3742}
3743EXPORT_SYMBOL_GPL(gpiod_add_hogs);
3744
3745void gpiod_remove_hogs(struct gpiod_hog *hogs)
3746{
3747 struct gpiod_hog *hog;
3748
3749 mutex_lock(&gpio_machine_hogs_mutex);
3750 for (hog = &hogs[0]; hog->chip_label; hog++)
3751 list_del(&hog->list);
3752 mutex_unlock(&gpio_machine_hogs_mutex);
3753}
3754EXPORT_SYMBOL_GPL(gpiod_remove_hogs);
3755
3756static struct gpiod_lookup_table *gpiod_find_lookup_table(struct device *dev)
3757{
3758 const char *dev_id = dev ? dev_name(dev) : NULL;
3759 struct gpiod_lookup_table *table;
3760
3761 mutex_lock(&gpio_lookup_lock);
3762
3763 list_for_each_entry(table, &gpio_lookup_list, list) {
3764 if (table->dev_id && dev_id) {
3765 /*
3766 * Valid strings on both ends, must be identical to have
3767 * a match
3768 */
3769 if (!strcmp(table->dev_id, dev_id))
3770 goto found;
3771 } else {
3772 /*
3773 * One of the pointers is NULL, so both must be to have
3774 * a match
3775 */
3776 if (dev_id == table->dev_id)
3777 goto found;
3778 }
3779 }
3780 table = NULL;
3781
3782found:
3783 mutex_unlock(&gpio_lookup_lock);
3784 return table;
3785}
3786
3787static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id,
3788 unsigned int idx, unsigned long *flags)
3789{
3790 struct gpio_desc *desc = ERR_PTR(-ENOENT);
3791 struct gpiod_lookup_table *table;
3792 struct gpiod_lookup *p;
3793
3794 table = gpiod_find_lookup_table(dev);
3795 if (!table)
3796 return desc;
3797
3798 for (p = &table->table[0]; p->key; p++) {
3799 struct gpio_chip *gc;
3800
3801 /* idx must always match exactly */
3802 if (p->idx != idx)
3803 continue;
3804
3805 /* If the lookup entry has a con_id, require exact match */
3806 if (p->con_id && (!con_id || strcmp(p->con_id, con_id)))
3807 continue;
3808
3809 if (p->chip_hwnum == U16_MAX) {
3810 desc = gpio_name_to_desc(p->key);
3811 if (desc) {
3812 *flags = p->flags;
3813 return desc;
3814 }
3815
3816 dev_warn(dev, "cannot find GPIO line %s, deferring\n",
3817 p->key);
3818 return ERR_PTR(-EPROBE_DEFER);
3819 }
3820
3821 gc = find_chip_by_name(p->key);
3822
3823 if (!gc) {
3824 /*
3825 * As the lookup table indicates a chip with
3826 * p->key should exist, assume it may
3827 * still appear later and let the interested
3828 * consumer be probed again or let the Deferred
3829 * Probe infrastructure handle the error.
3830 */
3831 dev_warn(dev, "cannot find GPIO chip %s, deferring\n",
3832 p->key);
3833 return ERR_PTR(-EPROBE_DEFER);
3834 }
3835
3836 if (gc->ngpio <= p->chip_hwnum) {
3837 dev_err(dev,
3838 "requested GPIO %u (%u) is out of range [0..%u] for chip %s\n",
3839 idx, p->chip_hwnum, gc->ngpio - 1,
3840 gc->label);
3841 return ERR_PTR(-EINVAL);
3842 }
3843
3844 desc = gpiochip_get_desc(gc, p->chip_hwnum);
3845 *flags = p->flags;
3846
3847 return desc;
3848 }
3849
3850 return desc;
3851}
3852
3853static int platform_gpio_count(struct device *dev, const char *con_id)
3854{
3855 struct gpiod_lookup_table *table;
3856 struct gpiod_lookup *p;
3857 unsigned int count = 0;
3858
3859 table = gpiod_find_lookup_table(dev);
3860 if (!table)
3861 return -ENOENT;
3862
3863 for (p = &table->table[0]; p->key; p++) {
3864 if ((con_id && p->con_id && !strcmp(con_id, p->con_id)) ||
3865 (!con_id && !p->con_id))
3866 count++;
3867 }
3868 if (!count)
3869 return -ENOENT;
3870
3871 return count;
3872}
3873
3874static struct gpio_desc *gpiod_find_by_fwnode(struct fwnode_handle *fwnode,
3875 struct device *consumer,
3876 const char *con_id,
3877 unsigned int idx,
3878 enum gpiod_flags *flags,
3879 unsigned long *lookupflags)
3880{
3881 struct gpio_desc *desc = ERR_PTR(-ENOENT);
3882
3883 if (is_of_node(fwnode)) {
3884 dev_dbg(consumer, "using DT '%pfw' for '%s' GPIO lookup\n",
3885 fwnode, con_id);
3886 desc = of_find_gpio(to_of_node(fwnode), con_id, idx, lookupflags);
3887 } else if (is_acpi_node(fwnode)) {
3888 dev_dbg(consumer, "using ACPI '%pfw' for '%s' GPIO lookup\n",
3889 fwnode, con_id);
3890 desc = acpi_find_gpio(fwnode, con_id, idx, flags, lookupflags);
3891 } else if (is_software_node(fwnode)) {
3892 dev_dbg(consumer, "using swnode '%pfw' for '%s' GPIO lookup\n",
3893 fwnode, con_id);
3894 desc = swnode_find_gpio(fwnode, con_id, idx, lookupflags);
3895 }
3896
3897 return desc;
3898}
3899
3900static struct gpio_desc *gpiod_find_and_request(struct device *consumer,
3901 struct fwnode_handle *fwnode,
3902 const char *con_id,
3903 unsigned int idx,
3904 enum gpiod_flags flags,
3905 const char *label,
3906 bool platform_lookup_allowed)
3907{
3908 unsigned long lookupflags = GPIO_LOOKUP_FLAGS_DEFAULT;
3909 struct gpio_desc *desc = ERR_PTR(-ENOENT);
3910 int ret;
3911
3912 if (!IS_ERR_OR_NULL(fwnode))
3913 desc = gpiod_find_by_fwnode(fwnode, consumer, con_id, idx,
3914 &flags, &lookupflags);
3915
3916 if (gpiod_not_found(desc) && platform_lookup_allowed) {
3917 /*
3918 * Either we are not using DT or ACPI, or their lookup did not
3919 * return a result. In that case, use platform lookup as a
3920 * fallback.
3921 */
3922 dev_dbg(consumer, "using lookup tables for GPIO lookup\n");
3923 desc = gpiod_find(consumer, con_id, idx, &lookupflags);
3924 }
3925
3926 if (IS_ERR(desc)) {
3927 dev_dbg(consumer, "No GPIO consumer %s found\n", con_id);
3928 return desc;
3929 }
3930
3931 /*
3932 * If a connection label was passed use that, else attempt to use
3933 * the device name as label
3934 */
3935 ret = gpiod_request(desc, label);
3936 if (ret) {
3937 if (!(ret == -EBUSY && flags & GPIOD_FLAGS_BIT_NONEXCLUSIVE))
3938 return ERR_PTR(ret);
3939
3940 /*
3941 * This happens when there are several consumers for
3942 * the same GPIO line: we just return here without
3943 * further initialization. It is a bit of a hack.
3944 * This is necessary to support fixed regulators.
3945 *
3946 * FIXME: Make this more sane and safe.
3947 */
3948 dev_info(consumer,
3949 "nonexclusive access to GPIO for %s\n", con_id);
3950 return desc;
3951 }
3952
3953 ret = gpiod_configure_flags(desc, con_id, lookupflags, flags);
3954 if (ret < 0) {
3955 dev_dbg(consumer, "setup of GPIO %s failed\n", con_id);
3956 gpiod_put(desc);
3957 return ERR_PTR(ret);
3958 }
3959
3960 blocking_notifier_call_chain(&desc->gdev->notifier,
3961 GPIOLINE_CHANGED_REQUESTED, desc);
3962
3963 return desc;
3964}
3965
3966/**
3967 * fwnode_gpiod_get_index - obtain a GPIO from firmware node
3968 * @fwnode: handle of the firmware node
3969 * @con_id: function within the GPIO consumer
3970 * @index: index of the GPIO to obtain for the consumer
3971 * @flags: GPIO initialization flags
3972 * @label: label to attach to the requested GPIO
3973 *
3974 * This function can be used for drivers that get their configuration
3975 * from opaque firmware.
3976 *
3977 * The function properly finds the corresponding GPIO using whatever is the
3978 * underlying firmware interface and then makes sure that the GPIO
3979 * descriptor is requested before it is returned to the caller.
3980 *
3981 * Returns:
3982 * On successful request the GPIO pin is configured in accordance with
3983 * provided @flags.
3984 *
3985 * In case of error an ERR_PTR() is returned.
3986 */
3987struct gpio_desc *fwnode_gpiod_get_index(struct fwnode_handle *fwnode,
3988 const char *con_id,
3989 int index,
3990 enum gpiod_flags flags,
3991 const char *label)
3992{
3993 return gpiod_find_and_request(NULL, fwnode, con_id, index, flags, label, false);
3994}
3995EXPORT_SYMBOL_GPL(fwnode_gpiod_get_index);
3996
3997/**
3998 * gpiod_count - return the number of GPIOs associated with a device / function
3999 * or -ENOENT if no GPIO has been assigned to the requested function
4000 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4001 * @con_id: function within the GPIO consumer
4002 */
4003int gpiod_count(struct device *dev, const char *con_id)
4004{
4005 const struct fwnode_handle *fwnode = dev ? dev_fwnode(dev) : NULL;
4006 int count = -ENOENT;
4007
4008 if (is_of_node(fwnode))
4009 count = of_gpio_get_count(dev, con_id);
4010 else if (is_acpi_node(fwnode))
4011 count = acpi_gpio_count(dev, con_id);
4012 else if (is_software_node(fwnode))
4013 count = swnode_gpio_count(fwnode, con_id);
4014
4015 if (count < 0)
4016 count = platform_gpio_count(dev, con_id);
4017
4018 return count;
4019}
4020EXPORT_SYMBOL_GPL(gpiod_count);
4021
4022/**
4023 * gpiod_get - obtain a GPIO for a given GPIO function
4024 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4025 * @con_id: function within the GPIO consumer
4026 * @flags: optional GPIO initialization flags
4027 *
4028 * Return the GPIO descriptor corresponding to the function con_id of device
4029 * dev, -ENOENT if no GPIO has been assigned to the requested function, or
4030 * another IS_ERR() code if an error occurred while trying to acquire the GPIO.
4031 */
4032struct gpio_desc *__must_check gpiod_get(struct device *dev, const char *con_id,
4033 enum gpiod_flags flags)
4034{
4035 return gpiod_get_index(dev, con_id, 0, flags);
4036}
4037EXPORT_SYMBOL_GPL(gpiod_get);
4038
4039/**
4040 * gpiod_get_optional - obtain an optional GPIO for a given GPIO function
4041 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4042 * @con_id: function within the GPIO consumer
4043 * @flags: optional GPIO initialization flags
4044 *
4045 * This is equivalent to gpiod_get(), except that when no GPIO was assigned to
4046 * the requested function it will return NULL. This is convenient for drivers
4047 * that need to handle optional GPIOs.
4048 */
4049struct gpio_desc *__must_check gpiod_get_optional(struct device *dev,
4050 const char *con_id,
4051 enum gpiod_flags flags)
4052{
4053 return gpiod_get_index_optional(dev, con_id, 0, flags);
4054}
4055EXPORT_SYMBOL_GPL(gpiod_get_optional);
4056
4057
4058/**
4059 * gpiod_configure_flags - helper function to configure a given GPIO
4060 * @desc: gpio whose value will be assigned
4061 * @con_id: function within the GPIO consumer
4062 * @lflags: bitmask of gpio_lookup_flags GPIO_* values - returned from
4063 * of_find_gpio() or of_get_gpio_hog()
4064 * @dflags: gpiod_flags - optional GPIO initialization flags
4065 *
4066 * Return 0 on success, -ENOENT if no GPIO has been assigned to the
4067 * requested function and/or index, or another IS_ERR() code if an error
4068 * occurred while trying to acquire the GPIO.
4069 */
4070int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id,
4071 unsigned long lflags, enum gpiod_flags dflags)
4072{
4073 int ret;
4074
4075 if (lflags & GPIO_ACTIVE_LOW)
4076 set_bit(FLAG_ACTIVE_LOW, &desc->flags);
4077
4078 if (lflags & GPIO_OPEN_DRAIN)
4079 set_bit(FLAG_OPEN_DRAIN, &desc->flags);
4080 else if (dflags & GPIOD_FLAGS_BIT_OPEN_DRAIN) {
4081 /*
4082 * This enforces open drain mode from the consumer side.
4083 * This is necessary for some busses like I2C, but the lookup
4084 * should *REALLY* have specified them as open drain in the
4085 * first place, so print a little warning here.
4086 */
4087 set_bit(FLAG_OPEN_DRAIN, &desc->flags);
4088 gpiod_warn(desc,
4089 "enforced open drain please flag it properly in DT/ACPI DSDT/board file\n");
4090 }
4091
4092 if (lflags & GPIO_OPEN_SOURCE)
4093 set_bit(FLAG_OPEN_SOURCE, &desc->flags);
4094
4095 if (((lflags & GPIO_PULL_UP) && (lflags & GPIO_PULL_DOWN)) ||
4096 ((lflags & GPIO_PULL_UP) && (lflags & GPIO_PULL_DISABLE)) ||
4097 ((lflags & GPIO_PULL_DOWN) && (lflags & GPIO_PULL_DISABLE))) {
4098 gpiod_err(desc,
4099 "multiple pull-up, pull-down or pull-disable enabled, invalid configuration\n");
4100 return -EINVAL;
4101 }
4102
4103 if (lflags & GPIO_PULL_UP)
4104 set_bit(FLAG_PULL_UP, &desc->flags);
4105 else if (lflags & GPIO_PULL_DOWN)
4106 set_bit(FLAG_PULL_DOWN, &desc->flags);
4107 else if (lflags & GPIO_PULL_DISABLE)
4108 set_bit(FLAG_BIAS_DISABLE, &desc->flags);
4109
4110 ret = gpiod_set_transitory(desc, (lflags & GPIO_TRANSITORY));
4111 if (ret < 0)
4112 return ret;
4113
4114 /* No particular flag request, return here... */
4115 if (!(dflags & GPIOD_FLAGS_BIT_DIR_SET)) {
4116 gpiod_dbg(desc, "no flags found for %s\n", con_id);
4117 return 0;
4118 }
4119
4120 /* Process flags */
4121 if (dflags & GPIOD_FLAGS_BIT_DIR_OUT)
4122 ret = gpiod_direction_output(desc,
4123 !!(dflags & GPIOD_FLAGS_BIT_DIR_VAL));
4124 else
4125 ret = gpiod_direction_input(desc);
4126
4127 return ret;
4128}
4129
4130/**
4131 * gpiod_get_index - obtain a GPIO from a multi-index GPIO function
4132 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4133 * @con_id: function within the GPIO consumer
4134 * @idx: index of the GPIO to obtain in the consumer
4135 * @flags: optional GPIO initialization flags
4136 *
4137 * This variant of gpiod_get() allows to access GPIOs other than the first
4138 * defined one for functions that define several GPIOs.
4139 *
4140 * Return a valid GPIO descriptor, -ENOENT if no GPIO has been assigned to the
4141 * requested function and/or index, or another IS_ERR() code if an error
4142 * occurred while trying to acquire the GPIO.
4143 */
4144struct gpio_desc *__must_check gpiod_get_index(struct device *dev,
4145 const char *con_id,
4146 unsigned int idx,
4147 enum gpiod_flags flags)
4148{
4149 struct fwnode_handle *fwnode = dev ? dev_fwnode(dev) : NULL;
4150 const char *devname = dev ? dev_name(dev) : "?";
4151 const char *label = con_id ?: devname;
4152
4153 return gpiod_find_and_request(dev, fwnode, con_id, idx, flags, label, true);
4154}
4155EXPORT_SYMBOL_GPL(gpiod_get_index);
4156
4157/**
4158 * gpiod_get_index_optional - obtain an optional GPIO from a multi-index GPIO
4159 * function
4160 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4161 * @con_id: function within the GPIO consumer
4162 * @index: index of the GPIO to obtain in the consumer
4163 * @flags: optional GPIO initialization flags
4164 *
4165 * This is equivalent to gpiod_get_index(), except that when no GPIO with the
4166 * specified index was assigned to the requested function it will return NULL.
4167 * This is convenient for drivers that need to handle optional GPIOs.
4168 */
4169struct gpio_desc *__must_check gpiod_get_index_optional(struct device *dev,
4170 const char *con_id,
4171 unsigned int index,
4172 enum gpiod_flags flags)
4173{
4174 struct gpio_desc *desc;
4175
4176 desc = gpiod_get_index(dev, con_id, index, flags);
4177 if (gpiod_not_found(desc))
4178 return NULL;
4179
4180 return desc;
4181}
4182EXPORT_SYMBOL_GPL(gpiod_get_index_optional);
4183
4184/**
4185 * gpiod_hog - Hog the specified GPIO desc given the provided flags
4186 * @desc: gpio whose value will be assigned
4187 * @name: gpio line name
4188 * @lflags: bitmask of gpio_lookup_flags GPIO_* values - returned from
4189 * of_find_gpio() or of_get_gpio_hog()
4190 * @dflags: gpiod_flags - optional GPIO initialization flags
4191 */
4192int gpiod_hog(struct gpio_desc *desc, const char *name,
4193 unsigned long lflags, enum gpiod_flags dflags)
4194{
4195 struct gpio_chip *gc;
4196 struct gpio_desc *local_desc;
4197 int hwnum;
4198 int ret;
4199
4200 gc = gpiod_to_chip(desc);
4201 hwnum = gpio_chip_hwgpio(desc);
4202
4203 local_desc = gpiochip_request_own_desc(gc, hwnum, name,
4204 lflags, dflags);
4205 if (IS_ERR(local_desc)) {
4206 ret = PTR_ERR(local_desc);
4207 pr_err("requesting hog GPIO %s (chip %s, offset %d) failed, %d\n",
4208 name, gc->label, hwnum, ret);
4209 return ret;
4210 }
4211
4212 /* Mark GPIO as hogged so it can be identified and removed later */
4213 set_bit(FLAG_IS_HOGGED, &desc->flags);
4214
4215 gpiod_info(desc, "hogged as %s%s\n",
4216 (dflags & GPIOD_FLAGS_BIT_DIR_OUT) ? "output" : "input",
4217 (dflags & GPIOD_FLAGS_BIT_DIR_OUT) ?
4218 (dflags & GPIOD_FLAGS_BIT_DIR_VAL) ? "/high" : "/low" : "");
4219
4220 return 0;
4221}
4222
4223/**
4224 * gpiochip_free_hogs - Scan gpio-controller chip and release GPIO hog
4225 * @gc: gpio chip to act on
4226 */
4227static void gpiochip_free_hogs(struct gpio_chip *gc)
4228{
4229 struct gpio_desc *desc;
4230
4231 for_each_gpio_desc_with_flag(gc, desc, FLAG_IS_HOGGED)
4232 gpiochip_free_own_desc(desc);
4233}
4234
4235/**
4236 * gpiod_get_array - obtain multiple GPIOs from a multi-index GPIO function
4237 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4238 * @con_id: function within the GPIO consumer
4239 * @flags: optional GPIO initialization flags
4240 *
4241 * This function acquires all the GPIOs defined under a given function.
4242 *
4243 * Return a struct gpio_descs containing an array of descriptors, -ENOENT if
4244 * no GPIO has been assigned to the requested function, or another IS_ERR()
4245 * code if an error occurred while trying to acquire the GPIOs.
4246 */
4247struct gpio_descs *__must_check gpiod_get_array(struct device *dev,
4248 const char *con_id,
4249 enum gpiod_flags flags)
4250{
4251 struct gpio_desc *desc;
4252 struct gpio_descs *descs;
4253 struct gpio_array *array_info = NULL;
4254 struct gpio_chip *gc;
4255 int count, bitmap_size;
4256
4257 count = gpiod_count(dev, con_id);
4258 if (count < 0)
4259 return ERR_PTR(count);
4260
4261 descs = kzalloc(struct_size(descs, desc, count), GFP_KERNEL);
4262 if (!descs)
4263 return ERR_PTR(-ENOMEM);
4264
4265 for (descs->ndescs = 0; descs->ndescs < count; ) {
4266 desc = gpiod_get_index(dev, con_id, descs->ndescs, flags);
4267 if (IS_ERR(desc)) {
4268 gpiod_put_array(descs);
4269 return ERR_CAST(desc);
4270 }
4271
4272 descs->desc[descs->ndescs] = desc;
4273
4274 gc = gpiod_to_chip(desc);
4275 /*
4276 * If pin hardware number of array member 0 is also 0, select
4277 * its chip as a candidate for fast bitmap processing path.
4278 */
4279 if (descs->ndescs == 0 && gpio_chip_hwgpio(desc) == 0) {
4280 struct gpio_descs *array;
4281
4282 bitmap_size = BITS_TO_LONGS(gc->ngpio > count ?
4283 gc->ngpio : count);
4284
4285 array = kzalloc(struct_size(descs, desc, count) +
4286 struct_size(array_info, invert_mask,
4287 3 * bitmap_size), GFP_KERNEL);
4288 if (!array) {
4289 gpiod_put_array(descs);
4290 return ERR_PTR(-ENOMEM);
4291 }
4292
4293 memcpy(array, descs,
4294 struct_size(descs, desc, descs->ndescs + 1));
4295 kfree(descs);
4296
4297 descs = array;
4298 array_info = (void *)(descs->desc + count);
4299 array_info->get_mask = array_info->invert_mask +
4300 bitmap_size;
4301 array_info->set_mask = array_info->get_mask +
4302 bitmap_size;
4303
4304 array_info->desc = descs->desc;
4305 array_info->size = count;
4306 array_info->chip = gc;
4307 bitmap_set(array_info->get_mask, descs->ndescs,
4308 count - descs->ndescs);
4309 bitmap_set(array_info->set_mask, descs->ndescs,
4310 count - descs->ndescs);
4311 descs->info = array_info;
4312 }
4313 /* Unmark array members which don't belong to the 'fast' chip */
4314 if (array_info && array_info->chip != gc) {
4315 __clear_bit(descs->ndescs, array_info->get_mask);
4316 __clear_bit(descs->ndescs, array_info->set_mask);
4317 }
4318 /*
4319 * Detect array members which belong to the 'fast' chip
4320 * but their pins are not in hardware order.
4321 */
4322 else if (array_info &&
4323 gpio_chip_hwgpio(desc) != descs->ndescs) {
4324 /*
4325 * Don't use fast path if all array members processed so
4326 * far belong to the same chip as this one but its pin
4327 * hardware number is different from its array index.
4328 */
4329 if (bitmap_full(array_info->get_mask, descs->ndescs)) {
4330 array_info = NULL;
4331 } else {
4332 __clear_bit(descs->ndescs,
4333 array_info->get_mask);
4334 __clear_bit(descs->ndescs,
4335 array_info->set_mask);
4336 }
4337 } else if (array_info) {
4338 /* Exclude open drain or open source from fast output */
4339 if (gpiochip_line_is_open_drain(gc, descs->ndescs) ||
4340 gpiochip_line_is_open_source(gc, descs->ndescs))
4341 __clear_bit(descs->ndescs,
4342 array_info->set_mask);
4343 /* Identify 'fast' pins which require invertion */
4344 if (gpiod_is_active_low(desc))
4345 __set_bit(descs->ndescs,
4346 array_info->invert_mask);
4347 }
4348
4349 descs->ndescs++;
4350 }
4351 if (array_info)
4352 dev_dbg(dev,
4353 "GPIO array info: chip=%s, size=%d, get_mask=%lx, set_mask=%lx, invert_mask=%lx\n",
4354 array_info->chip->label, array_info->size,
4355 *array_info->get_mask, *array_info->set_mask,
4356 *array_info->invert_mask);
4357 return descs;
4358}
4359EXPORT_SYMBOL_GPL(gpiod_get_array);
4360
4361/**
4362 * gpiod_get_array_optional - obtain multiple GPIOs from a multi-index GPIO
4363 * function
4364 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4365 * @con_id: function within the GPIO consumer
4366 * @flags: optional GPIO initialization flags
4367 *
4368 * This is equivalent to gpiod_get_array(), except that when no GPIO was
4369 * assigned to the requested function it will return NULL.
4370 */
4371struct gpio_descs *__must_check gpiod_get_array_optional(struct device *dev,
4372 const char *con_id,
4373 enum gpiod_flags flags)
4374{
4375 struct gpio_descs *descs;
4376
4377 descs = gpiod_get_array(dev, con_id, flags);
4378 if (gpiod_not_found(descs))
4379 return NULL;
4380
4381 return descs;
4382}
4383EXPORT_SYMBOL_GPL(gpiod_get_array_optional);
4384
4385/**
4386 * gpiod_put - dispose of a GPIO descriptor
4387 * @desc: GPIO descriptor to dispose of
4388 *
4389 * No descriptor can be used after gpiod_put() has been called on it.
4390 */
4391void gpiod_put(struct gpio_desc *desc)
4392{
4393 if (desc)
4394 gpiod_free(desc);
4395}
4396EXPORT_SYMBOL_GPL(gpiod_put);
4397
4398/**
4399 * gpiod_put_array - dispose of multiple GPIO descriptors
4400 * @descs: struct gpio_descs containing an array of descriptors
4401 */
4402void gpiod_put_array(struct gpio_descs *descs)
4403{
4404 unsigned int i;
4405
4406 for (i = 0; i < descs->ndescs; i++)
4407 gpiod_put(descs->desc[i]);
4408
4409 kfree(descs);
4410}
4411EXPORT_SYMBOL_GPL(gpiod_put_array);
4412
4413
4414static int gpio_bus_match(struct device *dev, struct device_driver *drv)
4415{
4416 struct fwnode_handle *fwnode = dev_fwnode(dev);
4417
4418 /*
4419 * Only match if the fwnode doesn't already have a proper struct device
4420 * created for it.
4421 */
4422 if (fwnode && fwnode->dev != dev)
4423 return 0;
4424 return 1;
4425}
4426
4427static int gpio_stub_drv_probe(struct device *dev)
4428{
4429 /*
4430 * The DT node of some GPIO chips have a "compatible" property, but
4431 * never have a struct device added and probed by a driver to register
4432 * the GPIO chip with gpiolib. In such cases, fw_devlink=on will cause
4433 * the consumers of the GPIO chip to get probe deferred forever because
4434 * they will be waiting for a device associated with the GPIO chip
4435 * firmware node to get added and bound to a driver.
4436 *
4437 * To allow these consumers to probe, we associate the struct
4438 * gpio_device of the GPIO chip with the firmware node and then simply
4439 * bind it to this stub driver.
4440 */
4441 return 0;
4442}
4443
4444static struct device_driver gpio_stub_drv = {
4445 .name = "gpio_stub_drv",
4446 .bus = &gpio_bus_type,
4447 .probe = gpio_stub_drv_probe,
4448};
4449
4450static int __init gpiolib_dev_init(void)
4451{
4452 int ret;
4453
4454 /* Register GPIO sysfs bus */
4455 ret = bus_register(&gpio_bus_type);
4456 if (ret < 0) {
4457 pr_err("gpiolib: could not register GPIO bus type\n");
4458 return ret;
4459 }
4460
4461 ret = driver_register(&gpio_stub_drv);
4462 if (ret < 0) {
4463 pr_err("gpiolib: could not register GPIO stub driver\n");
4464 bus_unregister(&gpio_bus_type);
4465 return ret;
4466 }
4467
4468 ret = alloc_chrdev_region(&gpio_devt, 0, GPIO_DEV_MAX, GPIOCHIP_NAME);
4469 if (ret < 0) {
4470 pr_err("gpiolib: failed to allocate char dev region\n");
4471 driver_unregister(&gpio_stub_drv);
4472 bus_unregister(&gpio_bus_type);
4473 return ret;
4474 }
4475
4476 gpiolib_initialized = true;
4477 gpiochip_setup_devs();
4478
4479#if IS_ENABLED(CONFIG_OF_DYNAMIC) && IS_ENABLED(CONFIG_OF_GPIO)
4480 WARN_ON(of_reconfig_notifier_register(&gpio_of_notifier));
4481#endif /* CONFIG_OF_DYNAMIC && CONFIG_OF_GPIO */
4482
4483 return ret;
4484}
4485core_initcall(gpiolib_dev_init);
4486
4487#ifdef CONFIG_DEBUG_FS
4488
4489static void gpiolib_dbg_show(struct seq_file *s, struct gpio_device *gdev)
4490{
4491 struct gpio_chip *gc = gdev->chip;
4492 struct gpio_desc *desc;
4493 unsigned gpio = gdev->base;
4494 int value;
4495 bool is_out;
4496 bool is_irq;
4497 bool active_low;
4498
4499 for_each_gpio_desc(gc, desc) {
4500 if (test_bit(FLAG_REQUESTED, &desc->flags)) {
4501 gpiod_get_direction(desc);
4502 is_out = test_bit(FLAG_IS_OUT, &desc->flags);
4503 value = gpio_chip_get_value(gc, desc);
4504 is_irq = test_bit(FLAG_USED_AS_IRQ, &desc->flags);
4505 active_low = test_bit(FLAG_ACTIVE_LOW, &desc->flags);
4506 seq_printf(s, " gpio-%-3d (%-20.20s|%-20.20s) %s %s %s%s\n",
4507 gpio, desc->name ?: "", desc->label,
4508 is_out ? "out" : "in ",
4509 value >= 0 ? (value ? "hi" : "lo") : "? ",
4510 is_irq ? "IRQ " : "",
4511 active_low ? "ACTIVE LOW" : "");
4512 } else if (desc->name) {
4513 seq_printf(s, " gpio-%-3d (%-20.20s)\n", gpio, desc->name);
4514 }
4515
4516 gpio++;
4517 }
4518}
4519
4520static void *gpiolib_seq_start(struct seq_file *s, loff_t *pos)
4521{
4522 unsigned long flags;
4523 struct gpio_device *gdev = NULL;
4524 loff_t index = *pos;
4525
4526 s->private = "";
4527
4528 spin_lock_irqsave(&gpio_lock, flags);
4529 list_for_each_entry(gdev, &gpio_devices, list)
4530 if (index-- == 0) {
4531 spin_unlock_irqrestore(&gpio_lock, flags);
4532 return gdev;
4533 }
4534 spin_unlock_irqrestore(&gpio_lock, flags);
4535
4536 return NULL;
4537}
4538
4539static void *gpiolib_seq_next(struct seq_file *s, void *v, loff_t *pos)
4540{
4541 unsigned long flags;
4542 struct gpio_device *gdev = v;
4543 void *ret = NULL;
4544
4545 spin_lock_irqsave(&gpio_lock, flags);
4546 if (list_is_last(&gdev->list, &gpio_devices))
4547 ret = NULL;
4548 else
4549 ret = list_first_entry(&gdev->list, struct gpio_device, list);
4550 spin_unlock_irqrestore(&gpio_lock, flags);
4551
4552 s->private = "\n";
4553 ++*pos;
4554
4555 return ret;
4556}
4557
4558static void gpiolib_seq_stop(struct seq_file *s, void *v)
4559{
4560}
4561
4562static int gpiolib_seq_show(struct seq_file *s, void *v)
4563{
4564 struct gpio_device *gdev = v;
4565 struct gpio_chip *gc = gdev->chip;
4566 struct device *parent;
4567
4568 if (!gc) {
4569 seq_printf(s, "%s%s: (dangling chip)", (char *)s->private,
4570 dev_name(&gdev->dev));
4571 return 0;
4572 }
4573
4574 seq_printf(s, "%s%s: GPIOs %d-%d", (char *)s->private,
4575 dev_name(&gdev->dev),
4576 gdev->base, gdev->base + gdev->ngpio - 1);
4577 parent = gc->parent;
4578 if (parent)
4579 seq_printf(s, ", parent: %s/%s",
4580 parent->bus ? parent->bus->name : "no-bus",
4581 dev_name(parent));
4582 if (gc->label)
4583 seq_printf(s, ", %s", gc->label);
4584 if (gc->can_sleep)
4585 seq_printf(s, ", can sleep");
4586 seq_printf(s, ":\n");
4587
4588 if (gc->dbg_show)
4589 gc->dbg_show(s, gc);
4590 else
4591 gpiolib_dbg_show(s, gdev);
4592
4593 return 0;
4594}
4595
4596static const struct seq_operations gpiolib_sops = {
4597 .start = gpiolib_seq_start,
4598 .next = gpiolib_seq_next,
4599 .stop = gpiolib_seq_stop,
4600 .show = gpiolib_seq_show,
4601};
4602DEFINE_SEQ_ATTRIBUTE(gpiolib);
4603
4604static int __init gpiolib_debugfs_init(void)
4605{
4606 /* /sys/kernel/debug/gpio */
4607 debugfs_create_file("gpio", 0444, NULL, NULL, &gpiolib_fops);
4608 return 0;
4609}
4610subsys_initcall(gpiolib_debugfs_init);
4611
4612#endif /* DEBUG_FS */
1// SPDX-License-Identifier: GPL-2.0
2#include <linux/bitmap.h>
3#include <linux/kernel.h>
4#include <linux/module.h>
5#include <linux/interrupt.h>
6#include <linux/irq.h>
7#include <linux/spinlock.h>
8#include <linux/list.h>
9#include <linux/device.h>
10#include <linux/err.h>
11#include <linux/debugfs.h>
12#include <linux/seq_file.h>
13#include <linux/gpio.h>
14#include <linux/idr.h>
15#include <linux/slab.h>
16#include <linux/acpi.h>
17#include <linux/gpio/driver.h>
18#include <linux/gpio/machine.h>
19#include <linux/pinctrl/consumer.h>
20#include <linux/cdev.h>
21#include <linux/fs.h>
22#include <linux/uaccess.h>
23#include <linux/compat.h>
24#include <linux/anon_inodes.h>
25#include <linux/file.h>
26#include <linux/kfifo.h>
27#include <linux/poll.h>
28#include <linux/timekeeping.h>
29#include <uapi/linux/gpio.h>
30
31#include "gpiolib.h"
32#include "gpiolib-of.h"
33#include "gpiolib-acpi.h"
34
35#define CREATE_TRACE_POINTS
36#include <trace/events/gpio.h>
37
38/* Implementation infrastructure for GPIO interfaces.
39 *
40 * The GPIO programming interface allows for inlining speed-critical
41 * get/set operations for common cases, so that access to SOC-integrated
42 * GPIOs can sometimes cost only an instruction or two per bit.
43 */
44
45
46/* When debugging, extend minimal trust to callers and platform code.
47 * Also emit diagnostic messages that may help initial bringup, when
48 * board setup or driver bugs are most common.
49 *
50 * Otherwise, minimize overhead in what may be bitbanging codepaths.
51 */
52#ifdef DEBUG
53#define extra_checks 1
54#else
55#define extra_checks 0
56#endif
57
58/* Device and char device-related information */
59static DEFINE_IDA(gpio_ida);
60static dev_t gpio_devt;
61#define GPIO_DEV_MAX 256 /* 256 GPIO chip devices supported */
62static struct bus_type gpio_bus_type = {
63 .name = "gpio",
64};
65
66/*
67 * Number of GPIOs to use for the fast path in set array
68 */
69#define FASTPATH_NGPIO CONFIG_GPIOLIB_FASTPATH_LIMIT
70
71/* gpio_lock prevents conflicts during gpio_desc[] table updates.
72 * While any GPIO is requested, its gpio_chip is not removable;
73 * each GPIO's "requested" flag serves as a lock and refcount.
74 */
75DEFINE_SPINLOCK(gpio_lock);
76
77static DEFINE_MUTEX(gpio_lookup_lock);
78static LIST_HEAD(gpio_lookup_list);
79LIST_HEAD(gpio_devices);
80
81static DEFINE_MUTEX(gpio_machine_hogs_mutex);
82static LIST_HEAD(gpio_machine_hogs);
83
84static void gpiochip_free_hogs(struct gpio_chip *chip);
85static int gpiochip_add_irqchip(struct gpio_chip *gpiochip,
86 struct lock_class_key *lock_key,
87 struct lock_class_key *request_key);
88static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip);
89static int gpiochip_irqchip_init_hw(struct gpio_chip *gpiochip);
90static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gpiochip);
91static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gpiochip);
92
93static bool gpiolib_initialized;
94
95static inline void desc_set_label(struct gpio_desc *d, const char *label)
96{
97 d->label = label;
98}
99
100/**
101 * gpio_to_desc - Convert a GPIO number to its descriptor
102 * @gpio: global GPIO number
103 *
104 * Returns:
105 * The GPIO descriptor associated with the given GPIO, or %NULL if no GPIO
106 * with the given number exists in the system.
107 */
108struct gpio_desc *gpio_to_desc(unsigned gpio)
109{
110 struct gpio_device *gdev;
111 unsigned long flags;
112
113 spin_lock_irqsave(&gpio_lock, flags);
114
115 list_for_each_entry(gdev, &gpio_devices, list) {
116 if (gdev->base <= gpio &&
117 gdev->base + gdev->ngpio > gpio) {
118 spin_unlock_irqrestore(&gpio_lock, flags);
119 return &gdev->descs[gpio - gdev->base];
120 }
121 }
122
123 spin_unlock_irqrestore(&gpio_lock, flags);
124
125 if (!gpio_is_valid(gpio))
126 WARN(1, "invalid GPIO %d\n", gpio);
127
128 return NULL;
129}
130EXPORT_SYMBOL_GPL(gpio_to_desc);
131
132/**
133 * gpiochip_get_desc - get the GPIO descriptor corresponding to the given
134 * hardware number for this chip
135 * @chip: GPIO chip
136 * @hwnum: hardware number of the GPIO for this chip
137 *
138 * Returns:
139 * A pointer to the GPIO descriptor or %ERR_PTR(-EINVAL) if no GPIO exists
140 * in the given chip for the specified hardware number.
141 */
142struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip,
143 u16 hwnum)
144{
145 struct gpio_device *gdev = chip->gpiodev;
146
147 if (hwnum >= gdev->ngpio)
148 return ERR_PTR(-EINVAL);
149
150 return &gdev->descs[hwnum];
151}
152
153/**
154 * desc_to_gpio - convert a GPIO descriptor to the integer namespace
155 * @desc: GPIO descriptor
156 *
157 * This should disappear in the future but is needed since we still
158 * use GPIO numbers for error messages and sysfs nodes.
159 *
160 * Returns:
161 * The global GPIO number for the GPIO specified by its descriptor.
162 */
163int desc_to_gpio(const struct gpio_desc *desc)
164{
165 return desc->gdev->base + (desc - &desc->gdev->descs[0]);
166}
167EXPORT_SYMBOL_GPL(desc_to_gpio);
168
169
170/**
171 * gpiod_to_chip - Return the GPIO chip to which a GPIO descriptor belongs
172 * @desc: descriptor to return the chip of
173 */
174struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc)
175{
176 if (!desc || !desc->gdev)
177 return NULL;
178 return desc->gdev->chip;
179}
180EXPORT_SYMBOL_GPL(gpiod_to_chip);
181
182/* dynamic allocation of GPIOs, e.g. on a hotplugged device */
183static int gpiochip_find_base(int ngpio)
184{
185 struct gpio_device *gdev;
186 int base = ARCH_NR_GPIOS - ngpio;
187
188 list_for_each_entry_reverse(gdev, &gpio_devices, list) {
189 /* found a free space? */
190 if (gdev->base + gdev->ngpio <= base)
191 break;
192 else
193 /* nope, check the space right before the chip */
194 base = gdev->base - ngpio;
195 }
196
197 if (gpio_is_valid(base)) {
198 pr_debug("%s: found new base at %d\n", __func__, base);
199 return base;
200 } else {
201 pr_err("%s: cannot find free range\n", __func__);
202 return -ENOSPC;
203 }
204}
205
206/**
207 * gpiod_get_direction - return the current direction of a GPIO
208 * @desc: GPIO to get the direction of
209 *
210 * Returns 0 for output, 1 for input, or an error code in case of error.
211 *
212 * This function may sleep if gpiod_cansleep() is true.
213 */
214int gpiod_get_direction(struct gpio_desc *desc)
215{
216 struct gpio_chip *chip;
217 unsigned offset;
218 int ret;
219
220 chip = gpiod_to_chip(desc);
221 offset = gpio_chip_hwgpio(desc);
222
223 if (!chip->get_direction)
224 return -ENOTSUPP;
225
226 ret = chip->get_direction(chip, offset);
227 if (ret > 0) {
228 /* GPIOF_DIR_IN, or other positive */
229 ret = 1;
230 clear_bit(FLAG_IS_OUT, &desc->flags);
231 }
232 if (ret == 0) {
233 /* GPIOF_DIR_OUT */
234 set_bit(FLAG_IS_OUT, &desc->flags);
235 }
236 return ret;
237}
238EXPORT_SYMBOL_GPL(gpiod_get_direction);
239
240/*
241 * Add a new chip to the global chips list, keeping the list of chips sorted
242 * by range(means [base, base + ngpio - 1]) order.
243 *
244 * Return -EBUSY if the new chip overlaps with some other chip's integer
245 * space.
246 */
247static int gpiodev_add_to_list(struct gpio_device *gdev)
248{
249 struct gpio_device *prev, *next;
250
251 if (list_empty(&gpio_devices)) {
252 /* initial entry in list */
253 list_add_tail(&gdev->list, &gpio_devices);
254 return 0;
255 }
256
257 next = list_entry(gpio_devices.next, struct gpio_device, list);
258 if (gdev->base + gdev->ngpio <= next->base) {
259 /* add before first entry */
260 list_add(&gdev->list, &gpio_devices);
261 return 0;
262 }
263
264 prev = list_entry(gpio_devices.prev, struct gpio_device, list);
265 if (prev->base + prev->ngpio <= gdev->base) {
266 /* add behind last entry */
267 list_add_tail(&gdev->list, &gpio_devices);
268 return 0;
269 }
270
271 list_for_each_entry_safe(prev, next, &gpio_devices, list) {
272 /* at the end of the list */
273 if (&next->list == &gpio_devices)
274 break;
275
276 /* add between prev and next */
277 if (prev->base + prev->ngpio <= gdev->base
278 && gdev->base + gdev->ngpio <= next->base) {
279 list_add(&gdev->list, &prev->list);
280 return 0;
281 }
282 }
283
284 dev_err(&gdev->dev, "GPIO integer space overlap, cannot add chip\n");
285 return -EBUSY;
286}
287
288/*
289 * Convert a GPIO name to its descriptor
290 */
291static struct gpio_desc *gpio_name_to_desc(const char * const name)
292{
293 struct gpio_device *gdev;
294 unsigned long flags;
295
296 spin_lock_irqsave(&gpio_lock, flags);
297
298 list_for_each_entry(gdev, &gpio_devices, list) {
299 int i;
300
301 for (i = 0; i != gdev->ngpio; ++i) {
302 struct gpio_desc *desc = &gdev->descs[i];
303
304 if (!desc->name || !name)
305 continue;
306
307 if (!strcmp(desc->name, name)) {
308 spin_unlock_irqrestore(&gpio_lock, flags);
309 return desc;
310 }
311 }
312 }
313
314 spin_unlock_irqrestore(&gpio_lock, flags);
315
316 return NULL;
317}
318
319/*
320 * Takes the names from gc->names and checks if they are all unique. If they
321 * are, they are assigned to their gpio descriptors.
322 *
323 * Warning if one of the names is already used for a different GPIO.
324 */
325static int gpiochip_set_desc_names(struct gpio_chip *gc)
326{
327 struct gpio_device *gdev = gc->gpiodev;
328 int i;
329
330 if (!gc->names)
331 return 0;
332
333 /* First check all names if they are unique */
334 for (i = 0; i != gc->ngpio; ++i) {
335 struct gpio_desc *gpio;
336
337 gpio = gpio_name_to_desc(gc->names[i]);
338 if (gpio)
339 dev_warn(&gdev->dev,
340 "Detected name collision for GPIO name '%s'\n",
341 gc->names[i]);
342 }
343
344 /* Then add all names to the GPIO descriptors */
345 for (i = 0; i != gc->ngpio; ++i)
346 gdev->descs[i].name = gc->names[i];
347
348 return 0;
349}
350
351static unsigned long *gpiochip_allocate_mask(struct gpio_chip *chip)
352{
353 unsigned long *p;
354
355 p = bitmap_alloc(chip->ngpio, GFP_KERNEL);
356 if (!p)
357 return NULL;
358
359 /* Assume by default all GPIOs are valid */
360 bitmap_fill(p, chip->ngpio);
361
362 return p;
363}
364
365static int gpiochip_alloc_valid_mask(struct gpio_chip *gc)
366{
367 if (!(of_gpio_need_valid_mask(gc) || gc->init_valid_mask))
368 return 0;
369
370 gc->valid_mask = gpiochip_allocate_mask(gc);
371 if (!gc->valid_mask)
372 return -ENOMEM;
373
374 return 0;
375}
376
377static int gpiochip_init_valid_mask(struct gpio_chip *gc)
378{
379 if (gc->init_valid_mask)
380 return gc->init_valid_mask(gc,
381 gc->valid_mask,
382 gc->ngpio);
383
384 return 0;
385}
386
387static void gpiochip_free_valid_mask(struct gpio_chip *gpiochip)
388{
389 bitmap_free(gpiochip->valid_mask);
390 gpiochip->valid_mask = NULL;
391}
392
393bool gpiochip_line_is_valid(const struct gpio_chip *gpiochip,
394 unsigned int offset)
395{
396 /* No mask means all valid */
397 if (likely(!gpiochip->valid_mask))
398 return true;
399 return test_bit(offset, gpiochip->valid_mask);
400}
401EXPORT_SYMBOL_GPL(gpiochip_line_is_valid);
402
403/*
404 * GPIO line handle management
405 */
406
407/**
408 * struct linehandle_state - contains the state of a userspace handle
409 * @gdev: the GPIO device the handle pertains to
410 * @label: consumer label used to tag descriptors
411 * @descs: the GPIO descriptors held by this handle
412 * @numdescs: the number of descriptors held in the descs array
413 */
414struct linehandle_state {
415 struct gpio_device *gdev;
416 const char *label;
417 struct gpio_desc *descs[GPIOHANDLES_MAX];
418 u32 numdescs;
419};
420
421#define GPIOHANDLE_REQUEST_VALID_FLAGS \
422 (GPIOHANDLE_REQUEST_INPUT | \
423 GPIOHANDLE_REQUEST_OUTPUT | \
424 GPIOHANDLE_REQUEST_ACTIVE_LOW | \
425 GPIOHANDLE_REQUEST_OPEN_DRAIN | \
426 GPIOHANDLE_REQUEST_OPEN_SOURCE)
427
428static long linehandle_ioctl(struct file *filep, unsigned int cmd,
429 unsigned long arg)
430{
431 struct linehandle_state *lh = filep->private_data;
432 void __user *ip = (void __user *)arg;
433 struct gpiohandle_data ghd;
434 DECLARE_BITMAP(vals, GPIOHANDLES_MAX);
435 int i;
436
437 if (cmd == GPIOHANDLE_GET_LINE_VALUES_IOCTL) {
438 /* NOTE: It's ok to read values of output lines. */
439 int ret = gpiod_get_array_value_complex(false,
440 true,
441 lh->numdescs,
442 lh->descs,
443 NULL,
444 vals);
445 if (ret)
446 return ret;
447
448 memset(&ghd, 0, sizeof(ghd));
449 for (i = 0; i < lh->numdescs; i++)
450 ghd.values[i] = test_bit(i, vals);
451
452 if (copy_to_user(ip, &ghd, sizeof(ghd)))
453 return -EFAULT;
454
455 return 0;
456 } else if (cmd == GPIOHANDLE_SET_LINE_VALUES_IOCTL) {
457 /*
458 * All line descriptors were created at once with the same
459 * flags so just check if the first one is really output.
460 */
461 if (!test_bit(FLAG_IS_OUT, &lh->descs[0]->flags))
462 return -EPERM;
463
464 if (copy_from_user(&ghd, ip, sizeof(ghd)))
465 return -EFAULT;
466
467 /* Clamp all values to [0,1] */
468 for (i = 0; i < lh->numdescs; i++)
469 __assign_bit(i, vals, ghd.values[i]);
470
471 /* Reuse the array setting function */
472 return gpiod_set_array_value_complex(false,
473 true,
474 lh->numdescs,
475 lh->descs,
476 NULL,
477 vals);
478 }
479 return -EINVAL;
480}
481
482#ifdef CONFIG_COMPAT
483static long linehandle_ioctl_compat(struct file *filep, unsigned int cmd,
484 unsigned long arg)
485{
486 return linehandle_ioctl(filep, cmd, (unsigned long)compat_ptr(arg));
487}
488#endif
489
490static int linehandle_release(struct inode *inode, struct file *filep)
491{
492 struct linehandle_state *lh = filep->private_data;
493 struct gpio_device *gdev = lh->gdev;
494 int i;
495
496 for (i = 0; i < lh->numdescs; i++)
497 gpiod_free(lh->descs[i]);
498 kfree(lh->label);
499 kfree(lh);
500 put_device(&gdev->dev);
501 return 0;
502}
503
504static const struct file_operations linehandle_fileops = {
505 .release = linehandle_release,
506 .owner = THIS_MODULE,
507 .llseek = noop_llseek,
508 .unlocked_ioctl = linehandle_ioctl,
509#ifdef CONFIG_COMPAT
510 .compat_ioctl = linehandle_ioctl_compat,
511#endif
512};
513
514static int linehandle_create(struct gpio_device *gdev, void __user *ip)
515{
516 struct gpiohandle_request handlereq;
517 struct linehandle_state *lh;
518 struct file *file;
519 int fd, i, count = 0, ret;
520 u32 lflags;
521
522 if (copy_from_user(&handlereq, ip, sizeof(handlereq)))
523 return -EFAULT;
524 if ((handlereq.lines == 0) || (handlereq.lines > GPIOHANDLES_MAX))
525 return -EINVAL;
526
527 lflags = handlereq.flags;
528
529 /* Return an error if an unknown flag is set */
530 if (lflags & ~GPIOHANDLE_REQUEST_VALID_FLAGS)
531 return -EINVAL;
532
533 /*
534 * Do not allow both INPUT & OUTPUT flags to be set as they are
535 * contradictory.
536 */
537 if ((lflags & GPIOHANDLE_REQUEST_INPUT) &&
538 (lflags & GPIOHANDLE_REQUEST_OUTPUT))
539 return -EINVAL;
540
541 /*
542 * Do not allow OPEN_SOURCE & OPEN_DRAIN flags in a single request. If
543 * the hardware actually supports enabling both at the same time the
544 * electrical result would be disastrous.
545 */
546 if ((lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN) &&
547 (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE))
548 return -EINVAL;
549
550 /* OPEN_DRAIN and OPEN_SOURCE flags only make sense for output mode. */
551 if (!(lflags & GPIOHANDLE_REQUEST_OUTPUT) &&
552 ((lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN) ||
553 (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE)))
554 return -EINVAL;
555
556 lh = kzalloc(sizeof(*lh), GFP_KERNEL);
557 if (!lh)
558 return -ENOMEM;
559 lh->gdev = gdev;
560 get_device(&gdev->dev);
561
562 /* Make sure this is terminated */
563 handlereq.consumer_label[sizeof(handlereq.consumer_label)-1] = '\0';
564 if (strlen(handlereq.consumer_label)) {
565 lh->label = kstrdup(handlereq.consumer_label,
566 GFP_KERNEL);
567 if (!lh->label) {
568 ret = -ENOMEM;
569 goto out_free_lh;
570 }
571 }
572
573 /* Request each GPIO */
574 for (i = 0; i < handlereq.lines; i++) {
575 u32 offset = handlereq.lineoffsets[i];
576 struct gpio_desc *desc;
577
578 if (offset >= gdev->ngpio) {
579 ret = -EINVAL;
580 goto out_free_descs;
581 }
582
583 desc = &gdev->descs[offset];
584 ret = gpiod_request(desc, lh->label);
585 if (ret)
586 goto out_free_descs;
587 lh->descs[i] = desc;
588 count = i + 1;
589
590 if (lflags & GPIOHANDLE_REQUEST_ACTIVE_LOW)
591 set_bit(FLAG_ACTIVE_LOW, &desc->flags);
592 if (lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN)
593 set_bit(FLAG_OPEN_DRAIN, &desc->flags);
594 if (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE)
595 set_bit(FLAG_OPEN_SOURCE, &desc->flags);
596
597 ret = gpiod_set_transitory(desc, false);
598 if (ret < 0)
599 goto out_free_descs;
600
601 /*
602 * Lines have to be requested explicitly for input
603 * or output, else the line will be treated "as is".
604 */
605 if (lflags & GPIOHANDLE_REQUEST_OUTPUT) {
606 int val = !!handlereq.default_values[i];
607
608 ret = gpiod_direction_output(desc, val);
609 if (ret)
610 goto out_free_descs;
611 } else if (lflags & GPIOHANDLE_REQUEST_INPUT) {
612 ret = gpiod_direction_input(desc);
613 if (ret)
614 goto out_free_descs;
615 }
616 dev_dbg(&gdev->dev, "registered chardev handle for line %d\n",
617 offset);
618 }
619 /* Let i point at the last handle */
620 i--;
621 lh->numdescs = handlereq.lines;
622
623 fd = get_unused_fd_flags(O_RDONLY | O_CLOEXEC);
624 if (fd < 0) {
625 ret = fd;
626 goto out_free_descs;
627 }
628
629 file = anon_inode_getfile("gpio-linehandle",
630 &linehandle_fileops,
631 lh,
632 O_RDONLY | O_CLOEXEC);
633 if (IS_ERR(file)) {
634 ret = PTR_ERR(file);
635 goto out_put_unused_fd;
636 }
637
638 handlereq.fd = fd;
639 if (copy_to_user(ip, &handlereq, sizeof(handlereq))) {
640 /*
641 * fput() will trigger the release() callback, so do not go onto
642 * the regular error cleanup path here.
643 */
644 fput(file);
645 put_unused_fd(fd);
646 return -EFAULT;
647 }
648
649 fd_install(fd, file);
650
651 dev_dbg(&gdev->dev, "registered chardev handle for %d lines\n",
652 lh->numdescs);
653
654 return 0;
655
656out_put_unused_fd:
657 put_unused_fd(fd);
658out_free_descs:
659 for (i = 0; i < count; i++)
660 gpiod_free(lh->descs[i]);
661 kfree(lh->label);
662out_free_lh:
663 kfree(lh);
664 put_device(&gdev->dev);
665 return ret;
666}
667
668/*
669 * GPIO line event management
670 */
671
672/**
673 * struct lineevent_state - contains the state of a userspace event
674 * @gdev: the GPIO device the event pertains to
675 * @label: consumer label used to tag descriptors
676 * @desc: the GPIO descriptor held by this event
677 * @eflags: the event flags this line was requested with
678 * @irq: the interrupt that trigger in response to events on this GPIO
679 * @wait: wait queue that handles blocking reads of events
680 * @events: KFIFO for the GPIO events
681 * @read_lock: mutex lock to protect reads from colliding with adding
682 * new events to the FIFO
683 * @timestamp: cache for the timestamp storing it between hardirq
684 * and IRQ thread, used to bring the timestamp close to the actual
685 * event
686 */
687struct lineevent_state {
688 struct gpio_device *gdev;
689 const char *label;
690 struct gpio_desc *desc;
691 u32 eflags;
692 int irq;
693 wait_queue_head_t wait;
694 DECLARE_KFIFO(events, struct gpioevent_data, 16);
695 struct mutex read_lock;
696 u64 timestamp;
697};
698
699#define GPIOEVENT_REQUEST_VALID_FLAGS \
700 (GPIOEVENT_REQUEST_RISING_EDGE | \
701 GPIOEVENT_REQUEST_FALLING_EDGE)
702
703static __poll_t lineevent_poll(struct file *filep,
704 struct poll_table_struct *wait)
705{
706 struct lineevent_state *le = filep->private_data;
707 __poll_t events = 0;
708
709 poll_wait(filep, &le->wait, wait);
710
711 if (!kfifo_is_empty(&le->events))
712 events = EPOLLIN | EPOLLRDNORM;
713
714 return events;
715}
716
717
718static ssize_t lineevent_read(struct file *filep,
719 char __user *buf,
720 size_t count,
721 loff_t *f_ps)
722{
723 struct lineevent_state *le = filep->private_data;
724 unsigned int copied;
725 int ret;
726
727 if (count < sizeof(struct gpioevent_data))
728 return -EINVAL;
729
730 do {
731 if (kfifo_is_empty(&le->events)) {
732 if (filep->f_flags & O_NONBLOCK)
733 return -EAGAIN;
734
735 ret = wait_event_interruptible(le->wait,
736 !kfifo_is_empty(&le->events));
737 if (ret)
738 return ret;
739 }
740
741 if (mutex_lock_interruptible(&le->read_lock))
742 return -ERESTARTSYS;
743 ret = kfifo_to_user(&le->events, buf, count, &copied);
744 mutex_unlock(&le->read_lock);
745
746 if (ret)
747 return ret;
748
749 /*
750 * If we couldn't read anything from the fifo (a different
751 * thread might have been faster) we either return -EAGAIN if
752 * the file descriptor is non-blocking, otherwise we go back to
753 * sleep and wait for more data to arrive.
754 */
755 if (copied == 0 && (filep->f_flags & O_NONBLOCK))
756 return -EAGAIN;
757
758 } while (copied == 0);
759
760 return copied;
761}
762
763static int lineevent_release(struct inode *inode, struct file *filep)
764{
765 struct lineevent_state *le = filep->private_data;
766 struct gpio_device *gdev = le->gdev;
767
768 free_irq(le->irq, le);
769 gpiod_free(le->desc);
770 kfree(le->label);
771 kfree(le);
772 put_device(&gdev->dev);
773 return 0;
774}
775
776static long lineevent_ioctl(struct file *filep, unsigned int cmd,
777 unsigned long arg)
778{
779 struct lineevent_state *le = filep->private_data;
780 void __user *ip = (void __user *)arg;
781 struct gpiohandle_data ghd;
782
783 /*
784 * We can get the value for an event line but not set it,
785 * because it is input by definition.
786 */
787 if (cmd == GPIOHANDLE_GET_LINE_VALUES_IOCTL) {
788 int val;
789
790 memset(&ghd, 0, sizeof(ghd));
791
792 val = gpiod_get_value_cansleep(le->desc);
793 if (val < 0)
794 return val;
795 ghd.values[0] = val;
796
797 if (copy_to_user(ip, &ghd, sizeof(ghd)))
798 return -EFAULT;
799
800 return 0;
801 }
802 return -EINVAL;
803}
804
805#ifdef CONFIG_COMPAT
806static long lineevent_ioctl_compat(struct file *filep, unsigned int cmd,
807 unsigned long arg)
808{
809 return lineevent_ioctl(filep, cmd, (unsigned long)compat_ptr(arg));
810}
811#endif
812
813static const struct file_operations lineevent_fileops = {
814 .release = lineevent_release,
815 .read = lineevent_read,
816 .poll = lineevent_poll,
817 .owner = THIS_MODULE,
818 .llseek = noop_llseek,
819 .unlocked_ioctl = lineevent_ioctl,
820#ifdef CONFIG_COMPAT
821 .compat_ioctl = lineevent_ioctl_compat,
822#endif
823};
824
825static irqreturn_t lineevent_irq_thread(int irq, void *p)
826{
827 struct lineevent_state *le = p;
828 struct gpioevent_data ge;
829 int ret;
830
831 /* Do not leak kernel stack to userspace */
832 memset(&ge, 0, sizeof(ge));
833
834 /*
835 * We may be running from a nested threaded interrupt in which case
836 * we didn't get the timestamp from lineevent_irq_handler().
837 */
838 if (!le->timestamp)
839 ge.timestamp = ktime_get_real_ns();
840 else
841 ge.timestamp = le->timestamp;
842
843 if (le->eflags & GPIOEVENT_REQUEST_RISING_EDGE
844 && le->eflags & GPIOEVENT_REQUEST_FALLING_EDGE) {
845 int level = gpiod_get_value_cansleep(le->desc);
846 if (level)
847 /* Emit low-to-high event */
848 ge.id = GPIOEVENT_EVENT_RISING_EDGE;
849 else
850 /* Emit high-to-low event */
851 ge.id = GPIOEVENT_EVENT_FALLING_EDGE;
852 } else if (le->eflags & GPIOEVENT_REQUEST_RISING_EDGE) {
853 /* Emit low-to-high event */
854 ge.id = GPIOEVENT_EVENT_RISING_EDGE;
855 } else if (le->eflags & GPIOEVENT_REQUEST_FALLING_EDGE) {
856 /* Emit high-to-low event */
857 ge.id = GPIOEVENT_EVENT_FALLING_EDGE;
858 } else {
859 return IRQ_NONE;
860 }
861
862 ret = kfifo_put(&le->events, ge);
863 if (ret)
864 wake_up_poll(&le->wait, EPOLLIN);
865
866 return IRQ_HANDLED;
867}
868
869static irqreturn_t lineevent_irq_handler(int irq, void *p)
870{
871 struct lineevent_state *le = p;
872
873 /*
874 * Just store the timestamp in hardirq context so we get it as
875 * close in time as possible to the actual event.
876 */
877 le->timestamp = ktime_get_real_ns();
878
879 return IRQ_WAKE_THREAD;
880}
881
882static int lineevent_create(struct gpio_device *gdev, void __user *ip)
883{
884 struct gpioevent_request eventreq;
885 struct lineevent_state *le;
886 struct gpio_desc *desc;
887 struct file *file;
888 u32 offset;
889 u32 lflags;
890 u32 eflags;
891 int fd;
892 int ret;
893 int irqflags = 0;
894
895 if (copy_from_user(&eventreq, ip, sizeof(eventreq)))
896 return -EFAULT;
897
898 le = kzalloc(sizeof(*le), GFP_KERNEL);
899 if (!le)
900 return -ENOMEM;
901 le->gdev = gdev;
902 get_device(&gdev->dev);
903
904 /* Make sure this is terminated */
905 eventreq.consumer_label[sizeof(eventreq.consumer_label)-1] = '\0';
906 if (strlen(eventreq.consumer_label)) {
907 le->label = kstrdup(eventreq.consumer_label,
908 GFP_KERNEL);
909 if (!le->label) {
910 ret = -ENOMEM;
911 goto out_free_le;
912 }
913 }
914
915 offset = eventreq.lineoffset;
916 lflags = eventreq.handleflags;
917 eflags = eventreq.eventflags;
918
919 if (offset >= gdev->ngpio) {
920 ret = -EINVAL;
921 goto out_free_label;
922 }
923
924 /* Return an error if a unknown flag is set */
925 if ((lflags & ~GPIOHANDLE_REQUEST_VALID_FLAGS) ||
926 (eflags & ~GPIOEVENT_REQUEST_VALID_FLAGS)) {
927 ret = -EINVAL;
928 goto out_free_label;
929 }
930
931 /* This is just wrong: we don't look for events on output lines */
932 if ((lflags & GPIOHANDLE_REQUEST_OUTPUT) ||
933 (lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN) ||
934 (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE)) {
935 ret = -EINVAL;
936 goto out_free_label;
937 }
938
939 desc = &gdev->descs[offset];
940 ret = gpiod_request(desc, le->label);
941 if (ret)
942 goto out_free_label;
943 le->desc = desc;
944 le->eflags = eflags;
945
946 if (lflags & GPIOHANDLE_REQUEST_ACTIVE_LOW)
947 set_bit(FLAG_ACTIVE_LOW, &desc->flags);
948
949 ret = gpiod_direction_input(desc);
950 if (ret)
951 goto out_free_desc;
952
953 le->irq = gpiod_to_irq(desc);
954 if (le->irq <= 0) {
955 ret = -ENODEV;
956 goto out_free_desc;
957 }
958
959 if (eflags & GPIOEVENT_REQUEST_RISING_EDGE)
960 irqflags |= test_bit(FLAG_ACTIVE_LOW, &desc->flags) ?
961 IRQF_TRIGGER_FALLING : IRQF_TRIGGER_RISING;
962 if (eflags & GPIOEVENT_REQUEST_FALLING_EDGE)
963 irqflags |= test_bit(FLAG_ACTIVE_LOW, &desc->flags) ?
964 IRQF_TRIGGER_RISING : IRQF_TRIGGER_FALLING;
965 irqflags |= IRQF_ONESHOT;
966
967 INIT_KFIFO(le->events);
968 init_waitqueue_head(&le->wait);
969 mutex_init(&le->read_lock);
970
971 /* Request a thread to read the events */
972 ret = request_threaded_irq(le->irq,
973 lineevent_irq_handler,
974 lineevent_irq_thread,
975 irqflags,
976 le->label,
977 le);
978 if (ret)
979 goto out_free_desc;
980
981 fd = get_unused_fd_flags(O_RDONLY | O_CLOEXEC);
982 if (fd < 0) {
983 ret = fd;
984 goto out_free_irq;
985 }
986
987 file = anon_inode_getfile("gpio-event",
988 &lineevent_fileops,
989 le,
990 O_RDONLY | O_CLOEXEC);
991 if (IS_ERR(file)) {
992 ret = PTR_ERR(file);
993 goto out_put_unused_fd;
994 }
995
996 eventreq.fd = fd;
997 if (copy_to_user(ip, &eventreq, sizeof(eventreq))) {
998 /*
999 * fput() will trigger the release() callback, so do not go onto
1000 * the regular error cleanup path here.
1001 */
1002 fput(file);
1003 put_unused_fd(fd);
1004 return -EFAULT;
1005 }
1006
1007 fd_install(fd, file);
1008
1009 return 0;
1010
1011out_put_unused_fd:
1012 put_unused_fd(fd);
1013out_free_irq:
1014 free_irq(le->irq, le);
1015out_free_desc:
1016 gpiod_free(le->desc);
1017out_free_label:
1018 kfree(le->label);
1019out_free_le:
1020 kfree(le);
1021 put_device(&gdev->dev);
1022 return ret;
1023}
1024
1025/*
1026 * gpio_ioctl() - ioctl handler for the GPIO chardev
1027 */
1028static long gpio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
1029{
1030 struct gpio_device *gdev = filp->private_data;
1031 struct gpio_chip *chip = gdev->chip;
1032 void __user *ip = (void __user *)arg;
1033
1034 /* We fail any subsequent ioctl():s when the chip is gone */
1035 if (!chip)
1036 return -ENODEV;
1037
1038 /* Fill in the struct and pass to userspace */
1039 if (cmd == GPIO_GET_CHIPINFO_IOCTL) {
1040 struct gpiochip_info chipinfo;
1041
1042 memset(&chipinfo, 0, sizeof(chipinfo));
1043
1044 strncpy(chipinfo.name, dev_name(&gdev->dev),
1045 sizeof(chipinfo.name));
1046 chipinfo.name[sizeof(chipinfo.name)-1] = '\0';
1047 strncpy(chipinfo.label, gdev->label,
1048 sizeof(chipinfo.label));
1049 chipinfo.label[sizeof(chipinfo.label)-1] = '\0';
1050 chipinfo.lines = gdev->ngpio;
1051 if (copy_to_user(ip, &chipinfo, sizeof(chipinfo)))
1052 return -EFAULT;
1053 return 0;
1054 } else if (cmd == GPIO_GET_LINEINFO_IOCTL) {
1055 struct gpioline_info lineinfo;
1056 struct gpio_desc *desc;
1057
1058 if (copy_from_user(&lineinfo, ip, sizeof(lineinfo)))
1059 return -EFAULT;
1060 if (lineinfo.line_offset >= gdev->ngpio)
1061 return -EINVAL;
1062
1063 desc = &gdev->descs[lineinfo.line_offset];
1064 if (desc->name) {
1065 strncpy(lineinfo.name, desc->name,
1066 sizeof(lineinfo.name));
1067 lineinfo.name[sizeof(lineinfo.name)-1] = '\0';
1068 } else {
1069 lineinfo.name[0] = '\0';
1070 }
1071 if (desc->label) {
1072 strncpy(lineinfo.consumer, desc->label,
1073 sizeof(lineinfo.consumer));
1074 lineinfo.consumer[sizeof(lineinfo.consumer)-1] = '\0';
1075 } else {
1076 lineinfo.consumer[0] = '\0';
1077 }
1078
1079 /*
1080 * Userspace only need to know that the kernel is using
1081 * this GPIO so it can't use it.
1082 */
1083 lineinfo.flags = 0;
1084 if (test_bit(FLAG_REQUESTED, &desc->flags) ||
1085 test_bit(FLAG_IS_HOGGED, &desc->flags) ||
1086 test_bit(FLAG_USED_AS_IRQ, &desc->flags) ||
1087 test_bit(FLAG_EXPORT, &desc->flags) ||
1088 test_bit(FLAG_SYSFS, &desc->flags) ||
1089 !pinctrl_gpio_can_use_line(chip->base + lineinfo.line_offset))
1090 lineinfo.flags |= GPIOLINE_FLAG_KERNEL;
1091 if (test_bit(FLAG_IS_OUT, &desc->flags))
1092 lineinfo.flags |= GPIOLINE_FLAG_IS_OUT;
1093 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
1094 lineinfo.flags |= GPIOLINE_FLAG_ACTIVE_LOW;
1095 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags))
1096 lineinfo.flags |= (GPIOLINE_FLAG_OPEN_DRAIN |
1097 GPIOLINE_FLAG_IS_OUT);
1098 if (test_bit(FLAG_OPEN_SOURCE, &desc->flags))
1099 lineinfo.flags |= (GPIOLINE_FLAG_OPEN_SOURCE |
1100 GPIOLINE_FLAG_IS_OUT);
1101
1102 if (copy_to_user(ip, &lineinfo, sizeof(lineinfo)))
1103 return -EFAULT;
1104 return 0;
1105 } else if (cmd == GPIO_GET_LINEHANDLE_IOCTL) {
1106 return linehandle_create(gdev, ip);
1107 } else if (cmd == GPIO_GET_LINEEVENT_IOCTL) {
1108 return lineevent_create(gdev, ip);
1109 }
1110 return -EINVAL;
1111}
1112
1113#ifdef CONFIG_COMPAT
1114static long gpio_ioctl_compat(struct file *filp, unsigned int cmd,
1115 unsigned long arg)
1116{
1117 return gpio_ioctl(filp, cmd, (unsigned long)compat_ptr(arg));
1118}
1119#endif
1120
1121/**
1122 * gpio_chrdev_open() - open the chardev for ioctl operations
1123 * @inode: inode for this chardev
1124 * @filp: file struct for storing private data
1125 * Returns 0 on success
1126 */
1127static int gpio_chrdev_open(struct inode *inode, struct file *filp)
1128{
1129 struct gpio_device *gdev = container_of(inode->i_cdev,
1130 struct gpio_device, chrdev);
1131
1132 /* Fail on open if the backing gpiochip is gone */
1133 if (!gdev->chip)
1134 return -ENODEV;
1135 get_device(&gdev->dev);
1136 filp->private_data = gdev;
1137
1138 return nonseekable_open(inode, filp);
1139}
1140
1141/**
1142 * gpio_chrdev_release() - close chardev after ioctl operations
1143 * @inode: inode for this chardev
1144 * @filp: file struct for storing private data
1145 * Returns 0 on success
1146 */
1147static int gpio_chrdev_release(struct inode *inode, struct file *filp)
1148{
1149 struct gpio_device *gdev = container_of(inode->i_cdev,
1150 struct gpio_device, chrdev);
1151
1152 put_device(&gdev->dev);
1153 return 0;
1154}
1155
1156
1157static const struct file_operations gpio_fileops = {
1158 .release = gpio_chrdev_release,
1159 .open = gpio_chrdev_open,
1160 .owner = THIS_MODULE,
1161 .llseek = no_llseek,
1162 .unlocked_ioctl = gpio_ioctl,
1163#ifdef CONFIG_COMPAT
1164 .compat_ioctl = gpio_ioctl_compat,
1165#endif
1166};
1167
1168static void gpiodevice_release(struct device *dev)
1169{
1170 struct gpio_device *gdev = dev_get_drvdata(dev);
1171
1172 list_del(&gdev->list);
1173 ida_simple_remove(&gpio_ida, gdev->id);
1174 kfree_const(gdev->label);
1175 kfree(gdev->descs);
1176 kfree(gdev);
1177}
1178
1179static int gpiochip_setup_dev(struct gpio_device *gdev)
1180{
1181 int ret;
1182
1183 cdev_init(&gdev->chrdev, &gpio_fileops);
1184 gdev->chrdev.owner = THIS_MODULE;
1185 gdev->dev.devt = MKDEV(MAJOR(gpio_devt), gdev->id);
1186
1187 ret = cdev_device_add(&gdev->chrdev, &gdev->dev);
1188 if (ret)
1189 return ret;
1190
1191 chip_dbg(gdev->chip, "added GPIO chardev (%d:%d)\n",
1192 MAJOR(gpio_devt), gdev->id);
1193
1194 ret = gpiochip_sysfs_register(gdev);
1195 if (ret)
1196 goto err_remove_device;
1197
1198 /* From this point, the .release() function cleans up gpio_device */
1199 gdev->dev.release = gpiodevice_release;
1200 pr_debug("%s: registered GPIOs %d to %d on device: %s (%s)\n",
1201 __func__, gdev->base, gdev->base + gdev->ngpio - 1,
1202 dev_name(&gdev->dev), gdev->chip->label ? : "generic");
1203
1204 return 0;
1205
1206err_remove_device:
1207 cdev_device_del(&gdev->chrdev, &gdev->dev);
1208 return ret;
1209}
1210
1211static void gpiochip_machine_hog(struct gpio_chip *chip, struct gpiod_hog *hog)
1212{
1213 struct gpio_desc *desc;
1214 int rv;
1215
1216 desc = gpiochip_get_desc(chip, hog->chip_hwnum);
1217 if (IS_ERR(desc)) {
1218 pr_err("%s: unable to get GPIO desc: %ld\n",
1219 __func__, PTR_ERR(desc));
1220 return;
1221 }
1222
1223 if (test_bit(FLAG_IS_HOGGED, &desc->flags))
1224 return;
1225
1226 rv = gpiod_hog(desc, hog->line_name, hog->lflags, hog->dflags);
1227 if (rv)
1228 pr_err("%s: unable to hog GPIO line (%s:%u): %d\n",
1229 __func__, chip->label, hog->chip_hwnum, rv);
1230}
1231
1232static void machine_gpiochip_add(struct gpio_chip *chip)
1233{
1234 struct gpiod_hog *hog;
1235
1236 mutex_lock(&gpio_machine_hogs_mutex);
1237
1238 list_for_each_entry(hog, &gpio_machine_hogs, list) {
1239 if (!strcmp(chip->label, hog->chip_label))
1240 gpiochip_machine_hog(chip, hog);
1241 }
1242
1243 mutex_unlock(&gpio_machine_hogs_mutex);
1244}
1245
1246static void gpiochip_setup_devs(void)
1247{
1248 struct gpio_device *gdev;
1249 int ret;
1250
1251 list_for_each_entry(gdev, &gpio_devices, list) {
1252 ret = gpiochip_setup_dev(gdev);
1253 if (ret)
1254 pr_err("%s: Failed to initialize gpio device (%d)\n",
1255 dev_name(&gdev->dev), ret);
1256 }
1257}
1258
1259int gpiochip_add_data_with_key(struct gpio_chip *chip, void *data,
1260 struct lock_class_key *lock_key,
1261 struct lock_class_key *request_key)
1262{
1263 unsigned long flags;
1264 int ret = 0;
1265 unsigned i;
1266 int base = chip->base;
1267 struct gpio_device *gdev;
1268
1269 /*
1270 * First: allocate and populate the internal stat container, and
1271 * set up the struct device.
1272 */
1273 gdev = kzalloc(sizeof(*gdev), GFP_KERNEL);
1274 if (!gdev)
1275 return -ENOMEM;
1276 gdev->dev.bus = &gpio_bus_type;
1277 gdev->chip = chip;
1278 chip->gpiodev = gdev;
1279 if (chip->parent) {
1280 gdev->dev.parent = chip->parent;
1281 gdev->dev.of_node = chip->parent->of_node;
1282 }
1283
1284#ifdef CONFIG_OF_GPIO
1285 /* If the gpiochip has an assigned OF node this takes precedence */
1286 if (chip->of_node)
1287 gdev->dev.of_node = chip->of_node;
1288 else
1289 chip->of_node = gdev->dev.of_node;
1290#endif
1291
1292 gdev->id = ida_simple_get(&gpio_ida, 0, 0, GFP_KERNEL);
1293 if (gdev->id < 0) {
1294 ret = gdev->id;
1295 goto err_free_gdev;
1296 }
1297 dev_set_name(&gdev->dev, "gpiochip%d", gdev->id);
1298 device_initialize(&gdev->dev);
1299 dev_set_drvdata(&gdev->dev, gdev);
1300 if (chip->parent && chip->parent->driver)
1301 gdev->owner = chip->parent->driver->owner;
1302 else if (chip->owner)
1303 /* TODO: remove chip->owner */
1304 gdev->owner = chip->owner;
1305 else
1306 gdev->owner = THIS_MODULE;
1307
1308 gdev->descs = kcalloc(chip->ngpio, sizeof(gdev->descs[0]), GFP_KERNEL);
1309 if (!gdev->descs) {
1310 ret = -ENOMEM;
1311 goto err_free_ida;
1312 }
1313
1314 if (chip->ngpio == 0) {
1315 chip_err(chip, "tried to insert a GPIO chip with zero lines\n");
1316 ret = -EINVAL;
1317 goto err_free_descs;
1318 }
1319
1320 if (chip->ngpio > FASTPATH_NGPIO)
1321 chip_warn(chip, "line cnt %u is greater than fast path cnt %u\n",
1322 chip->ngpio, FASTPATH_NGPIO);
1323
1324 gdev->label = kstrdup_const(chip->label ?: "unknown", GFP_KERNEL);
1325 if (!gdev->label) {
1326 ret = -ENOMEM;
1327 goto err_free_descs;
1328 }
1329
1330 gdev->ngpio = chip->ngpio;
1331 gdev->data = data;
1332
1333 spin_lock_irqsave(&gpio_lock, flags);
1334
1335 /*
1336 * TODO: this allocates a Linux GPIO number base in the global
1337 * GPIO numberspace for this chip. In the long run we want to
1338 * get *rid* of this numberspace and use only descriptors, but
1339 * it may be a pipe dream. It will not happen before we get rid
1340 * of the sysfs interface anyways.
1341 */
1342 if (base < 0) {
1343 base = gpiochip_find_base(chip->ngpio);
1344 if (base < 0) {
1345 ret = base;
1346 spin_unlock_irqrestore(&gpio_lock, flags);
1347 goto err_free_label;
1348 }
1349 /*
1350 * TODO: it should not be necessary to reflect the assigned
1351 * base outside of the GPIO subsystem. Go over drivers and
1352 * see if anyone makes use of this, else drop this and assign
1353 * a poison instead.
1354 */
1355 chip->base = base;
1356 }
1357 gdev->base = base;
1358
1359 ret = gpiodev_add_to_list(gdev);
1360 if (ret) {
1361 spin_unlock_irqrestore(&gpio_lock, flags);
1362 goto err_free_label;
1363 }
1364
1365 spin_unlock_irqrestore(&gpio_lock, flags);
1366
1367 for (i = 0; i < chip->ngpio; i++)
1368 gdev->descs[i].gdev = gdev;
1369
1370#ifdef CONFIG_PINCTRL
1371 INIT_LIST_HEAD(&gdev->pin_ranges);
1372#endif
1373
1374 ret = gpiochip_set_desc_names(chip);
1375 if (ret)
1376 goto err_remove_from_list;
1377
1378 ret = gpiochip_alloc_valid_mask(chip);
1379 if (ret)
1380 goto err_remove_from_list;
1381
1382 ret = of_gpiochip_add(chip);
1383 if (ret)
1384 goto err_free_gpiochip_mask;
1385
1386 ret = gpiochip_init_valid_mask(chip);
1387 if (ret)
1388 goto err_remove_of_chip;
1389
1390 for (i = 0; i < chip->ngpio; i++) {
1391 struct gpio_desc *desc = &gdev->descs[i];
1392
1393 if (chip->get_direction && gpiochip_line_is_valid(chip, i)) {
1394 if (!chip->get_direction(chip, i))
1395 set_bit(FLAG_IS_OUT, &desc->flags);
1396 else
1397 clear_bit(FLAG_IS_OUT, &desc->flags);
1398 } else {
1399 if (!chip->direction_input)
1400 set_bit(FLAG_IS_OUT, &desc->flags);
1401 else
1402 clear_bit(FLAG_IS_OUT, &desc->flags);
1403 }
1404 }
1405
1406 acpi_gpiochip_add(chip);
1407
1408 machine_gpiochip_add(chip);
1409
1410 ret = gpiochip_irqchip_init_hw(chip);
1411 if (ret)
1412 goto err_remove_acpi_chip;
1413
1414 ret = gpiochip_irqchip_init_valid_mask(chip);
1415 if (ret)
1416 goto err_remove_acpi_chip;
1417
1418 ret = gpiochip_add_irqchip(chip, lock_key, request_key);
1419 if (ret)
1420 goto err_remove_irqchip_mask;
1421
1422 /*
1423 * By first adding the chardev, and then adding the device,
1424 * we get a device node entry in sysfs under
1425 * /sys/bus/gpio/devices/gpiochipN/dev that can be used for
1426 * coldplug of device nodes and other udev business.
1427 * We can do this only if gpiolib has been initialized.
1428 * Otherwise, defer until later.
1429 */
1430 if (gpiolib_initialized) {
1431 ret = gpiochip_setup_dev(gdev);
1432 if (ret)
1433 goto err_remove_irqchip;
1434 }
1435 return 0;
1436
1437err_remove_irqchip:
1438 gpiochip_irqchip_remove(chip);
1439err_remove_irqchip_mask:
1440 gpiochip_irqchip_free_valid_mask(chip);
1441err_remove_acpi_chip:
1442 acpi_gpiochip_remove(chip);
1443err_remove_of_chip:
1444 gpiochip_free_hogs(chip);
1445 of_gpiochip_remove(chip);
1446err_free_gpiochip_mask:
1447 gpiochip_free_valid_mask(chip);
1448err_remove_from_list:
1449 spin_lock_irqsave(&gpio_lock, flags);
1450 list_del(&gdev->list);
1451 spin_unlock_irqrestore(&gpio_lock, flags);
1452err_free_label:
1453 kfree_const(gdev->label);
1454err_free_descs:
1455 kfree(gdev->descs);
1456err_free_ida:
1457 ida_simple_remove(&gpio_ida, gdev->id);
1458err_free_gdev:
1459 /* failures here can mean systems won't boot... */
1460 pr_err("%s: GPIOs %d..%d (%s) failed to register, %d\n", __func__,
1461 gdev->base, gdev->base + gdev->ngpio - 1,
1462 chip->label ? : "generic", ret);
1463 kfree(gdev);
1464 return ret;
1465}
1466EXPORT_SYMBOL_GPL(gpiochip_add_data_with_key);
1467
1468/**
1469 * gpiochip_get_data() - get per-subdriver data for the chip
1470 * @chip: GPIO chip
1471 *
1472 * Returns:
1473 * The per-subdriver data for the chip.
1474 */
1475void *gpiochip_get_data(struct gpio_chip *chip)
1476{
1477 return chip->gpiodev->data;
1478}
1479EXPORT_SYMBOL_GPL(gpiochip_get_data);
1480
1481/**
1482 * gpiochip_remove() - unregister a gpio_chip
1483 * @chip: the chip to unregister
1484 *
1485 * A gpio_chip with any GPIOs still requested may not be removed.
1486 */
1487void gpiochip_remove(struct gpio_chip *chip)
1488{
1489 struct gpio_device *gdev = chip->gpiodev;
1490 struct gpio_desc *desc;
1491 unsigned long flags;
1492 unsigned i;
1493 bool requested = false;
1494
1495 /* FIXME: should the legacy sysfs handling be moved to gpio_device? */
1496 gpiochip_sysfs_unregister(gdev);
1497 gpiochip_free_hogs(chip);
1498 /* Numb the device, cancelling all outstanding operations */
1499 gdev->chip = NULL;
1500 gpiochip_irqchip_remove(chip);
1501 acpi_gpiochip_remove(chip);
1502 gpiochip_remove_pin_ranges(chip);
1503 of_gpiochip_remove(chip);
1504 gpiochip_free_valid_mask(chip);
1505 /*
1506 * We accept no more calls into the driver from this point, so
1507 * NULL the driver data pointer
1508 */
1509 gdev->data = NULL;
1510
1511 spin_lock_irqsave(&gpio_lock, flags);
1512 for (i = 0; i < gdev->ngpio; i++) {
1513 desc = &gdev->descs[i];
1514 if (test_bit(FLAG_REQUESTED, &desc->flags))
1515 requested = true;
1516 }
1517 spin_unlock_irqrestore(&gpio_lock, flags);
1518
1519 if (requested)
1520 dev_crit(&gdev->dev,
1521 "REMOVING GPIOCHIP WITH GPIOS STILL REQUESTED\n");
1522
1523 /*
1524 * The gpiochip side puts its use of the device to rest here:
1525 * if there are no userspace clients, the chardev and device will
1526 * be removed, else it will be dangling until the last user is
1527 * gone.
1528 */
1529 cdev_device_del(&gdev->chrdev, &gdev->dev);
1530 put_device(&gdev->dev);
1531}
1532EXPORT_SYMBOL_GPL(gpiochip_remove);
1533
1534static void devm_gpio_chip_release(struct device *dev, void *res)
1535{
1536 struct gpio_chip *chip = *(struct gpio_chip **)res;
1537
1538 gpiochip_remove(chip);
1539}
1540
1541/**
1542 * devm_gpiochip_add_data() - Resource manager gpiochip_add_data()
1543 * @dev: pointer to the device that gpio_chip belongs to.
1544 * @chip: the chip to register, with chip->base initialized
1545 * @data: driver-private data associated with this chip
1546 *
1547 * Context: potentially before irqs will work
1548 *
1549 * The gpio chip automatically be released when the device is unbound.
1550 *
1551 * Returns:
1552 * A negative errno if the chip can't be registered, such as because the
1553 * chip->base is invalid or already associated with a different chip.
1554 * Otherwise it returns zero as a success code.
1555 */
1556int devm_gpiochip_add_data(struct device *dev, struct gpio_chip *chip,
1557 void *data)
1558{
1559 struct gpio_chip **ptr;
1560 int ret;
1561
1562 ptr = devres_alloc(devm_gpio_chip_release, sizeof(*ptr),
1563 GFP_KERNEL);
1564 if (!ptr)
1565 return -ENOMEM;
1566
1567 ret = gpiochip_add_data(chip, data);
1568 if (ret < 0) {
1569 devres_free(ptr);
1570 return ret;
1571 }
1572
1573 *ptr = chip;
1574 devres_add(dev, ptr);
1575
1576 return 0;
1577}
1578EXPORT_SYMBOL_GPL(devm_gpiochip_add_data);
1579
1580/**
1581 * gpiochip_find() - iterator for locating a specific gpio_chip
1582 * @data: data to pass to match function
1583 * @match: Callback function to check gpio_chip
1584 *
1585 * Similar to bus_find_device. It returns a reference to a gpio_chip as
1586 * determined by a user supplied @match callback. The callback should return
1587 * 0 if the device doesn't match and non-zero if it does. If the callback is
1588 * non-zero, this function will return to the caller and not iterate over any
1589 * more gpio_chips.
1590 */
1591struct gpio_chip *gpiochip_find(void *data,
1592 int (*match)(struct gpio_chip *chip,
1593 void *data))
1594{
1595 struct gpio_device *gdev;
1596 struct gpio_chip *chip = NULL;
1597 unsigned long flags;
1598
1599 spin_lock_irqsave(&gpio_lock, flags);
1600 list_for_each_entry(gdev, &gpio_devices, list)
1601 if (gdev->chip && match(gdev->chip, data)) {
1602 chip = gdev->chip;
1603 break;
1604 }
1605
1606 spin_unlock_irqrestore(&gpio_lock, flags);
1607
1608 return chip;
1609}
1610EXPORT_SYMBOL_GPL(gpiochip_find);
1611
1612static int gpiochip_match_name(struct gpio_chip *chip, void *data)
1613{
1614 const char *name = data;
1615
1616 return !strcmp(chip->label, name);
1617}
1618
1619static struct gpio_chip *find_chip_by_name(const char *name)
1620{
1621 return gpiochip_find((void *)name, gpiochip_match_name);
1622}
1623
1624#ifdef CONFIG_GPIOLIB_IRQCHIP
1625
1626/*
1627 * The following is irqchip helper code for gpiochips.
1628 */
1629
1630static int gpiochip_irqchip_init_hw(struct gpio_chip *gc)
1631{
1632 struct gpio_irq_chip *girq = &gc->irq;
1633
1634 if (!girq->init_hw)
1635 return 0;
1636
1637 return girq->init_hw(gc);
1638}
1639
1640static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gc)
1641{
1642 struct gpio_irq_chip *girq = &gc->irq;
1643
1644 if (!girq->init_valid_mask)
1645 return 0;
1646
1647 girq->valid_mask = gpiochip_allocate_mask(gc);
1648 if (!girq->valid_mask)
1649 return -ENOMEM;
1650
1651 girq->init_valid_mask(gc, girq->valid_mask, gc->ngpio);
1652
1653 return 0;
1654}
1655
1656static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gpiochip)
1657{
1658 bitmap_free(gpiochip->irq.valid_mask);
1659 gpiochip->irq.valid_mask = NULL;
1660}
1661
1662bool gpiochip_irqchip_irq_valid(const struct gpio_chip *gpiochip,
1663 unsigned int offset)
1664{
1665 if (!gpiochip_line_is_valid(gpiochip, offset))
1666 return false;
1667 /* No mask means all valid */
1668 if (likely(!gpiochip->irq.valid_mask))
1669 return true;
1670 return test_bit(offset, gpiochip->irq.valid_mask);
1671}
1672EXPORT_SYMBOL_GPL(gpiochip_irqchip_irq_valid);
1673
1674/**
1675 * gpiochip_set_cascaded_irqchip() - connects a cascaded irqchip to a gpiochip
1676 * @gc: the gpiochip to set the irqchip chain to
1677 * @parent_irq: the irq number corresponding to the parent IRQ for this
1678 * chained irqchip
1679 * @parent_handler: the parent interrupt handler for the accumulated IRQ
1680 * coming out of the gpiochip. If the interrupt is nested rather than
1681 * cascaded, pass NULL in this handler argument
1682 */
1683static void gpiochip_set_cascaded_irqchip(struct gpio_chip *gc,
1684 unsigned int parent_irq,
1685 irq_flow_handler_t parent_handler)
1686{
1687 struct gpio_irq_chip *girq = &gc->irq;
1688 struct device *dev = &gc->gpiodev->dev;
1689
1690 if (!girq->domain) {
1691 chip_err(gc, "called %s before setting up irqchip\n",
1692 __func__);
1693 return;
1694 }
1695
1696 if (parent_handler) {
1697 if (gc->can_sleep) {
1698 chip_err(gc,
1699 "you cannot have chained interrupts on a chip that may sleep\n");
1700 return;
1701 }
1702 girq->parents = devm_kcalloc(dev, 1,
1703 sizeof(*girq->parents),
1704 GFP_KERNEL);
1705 if (!girq->parents) {
1706 chip_err(gc, "out of memory allocating parent IRQ\n");
1707 return;
1708 }
1709 girq->parents[0] = parent_irq;
1710 girq->num_parents = 1;
1711 /*
1712 * The parent irqchip is already using the chip_data for this
1713 * irqchip, so our callbacks simply use the handler_data.
1714 */
1715 irq_set_chained_handler_and_data(parent_irq, parent_handler,
1716 gc);
1717 }
1718}
1719
1720/**
1721 * gpiochip_set_chained_irqchip() - connects a chained irqchip to a gpiochip
1722 * @gpiochip: the gpiochip to set the irqchip chain to
1723 * @irqchip: the irqchip to chain to the gpiochip
1724 * @parent_irq: the irq number corresponding to the parent IRQ for this
1725 * chained irqchip
1726 * @parent_handler: the parent interrupt handler for the accumulated IRQ
1727 * coming out of the gpiochip.
1728 */
1729void gpiochip_set_chained_irqchip(struct gpio_chip *gpiochip,
1730 struct irq_chip *irqchip,
1731 unsigned int parent_irq,
1732 irq_flow_handler_t parent_handler)
1733{
1734 if (gpiochip->irq.threaded) {
1735 chip_err(gpiochip, "tried to chain a threaded gpiochip\n");
1736 return;
1737 }
1738
1739 gpiochip_set_cascaded_irqchip(gpiochip, parent_irq, parent_handler);
1740}
1741EXPORT_SYMBOL_GPL(gpiochip_set_chained_irqchip);
1742
1743/**
1744 * gpiochip_set_nested_irqchip() - connects a nested irqchip to a gpiochip
1745 * @gpiochip: the gpiochip to set the irqchip nested handler to
1746 * @irqchip: the irqchip to nest to the gpiochip
1747 * @parent_irq: the irq number corresponding to the parent IRQ for this
1748 * nested irqchip
1749 */
1750void gpiochip_set_nested_irqchip(struct gpio_chip *gpiochip,
1751 struct irq_chip *irqchip,
1752 unsigned int parent_irq)
1753{
1754 gpiochip_set_cascaded_irqchip(gpiochip, parent_irq, NULL);
1755}
1756EXPORT_SYMBOL_GPL(gpiochip_set_nested_irqchip);
1757
1758#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
1759
1760/**
1761 * gpiochip_set_hierarchical_irqchip() - connects a hierarchical irqchip
1762 * to a gpiochip
1763 * @gc: the gpiochip to set the irqchip hierarchical handler to
1764 * @irqchip: the irqchip to handle this level of the hierarchy, the interrupt
1765 * will then percolate up to the parent
1766 */
1767static void gpiochip_set_hierarchical_irqchip(struct gpio_chip *gc,
1768 struct irq_chip *irqchip)
1769{
1770 /* DT will deal with mapping each IRQ as we go along */
1771 if (is_of_node(gc->irq.fwnode))
1772 return;
1773
1774 /*
1775 * This is for legacy and boardfile "irqchip" fwnodes: allocate
1776 * irqs upfront instead of dynamically since we don't have the
1777 * dynamic type of allocation that hardware description languages
1778 * provide. Once all GPIO drivers using board files are gone from
1779 * the kernel we can delete this code, but for a transitional period
1780 * it is necessary to keep this around.
1781 */
1782 if (is_fwnode_irqchip(gc->irq.fwnode)) {
1783 int i;
1784 int ret;
1785
1786 for (i = 0; i < gc->ngpio; i++) {
1787 struct irq_fwspec fwspec;
1788 unsigned int parent_hwirq;
1789 unsigned int parent_type;
1790 struct gpio_irq_chip *girq = &gc->irq;
1791
1792 /*
1793 * We call the child to parent translation function
1794 * only to check if the child IRQ is valid or not.
1795 * Just pick the rising edge type here as that is what
1796 * we likely need to support.
1797 */
1798 ret = girq->child_to_parent_hwirq(gc, i,
1799 IRQ_TYPE_EDGE_RISING,
1800 &parent_hwirq,
1801 &parent_type);
1802 if (ret) {
1803 chip_err(gc, "skip set-up on hwirq %d\n",
1804 i);
1805 continue;
1806 }
1807
1808 fwspec.fwnode = gc->irq.fwnode;
1809 /* This is the hwirq for the GPIO line side of things */
1810 fwspec.param[0] = girq->child_offset_to_irq(gc, i);
1811 /* Just pick something */
1812 fwspec.param[1] = IRQ_TYPE_EDGE_RISING;
1813 fwspec.param_count = 2;
1814 ret = __irq_domain_alloc_irqs(gc->irq.domain,
1815 /* just pick something */
1816 -1,
1817 1,
1818 NUMA_NO_NODE,
1819 &fwspec,
1820 false,
1821 NULL);
1822 if (ret < 0) {
1823 chip_err(gc,
1824 "can not allocate irq for GPIO line %d parent hwirq %d in hierarchy domain: %d\n",
1825 i, parent_hwirq,
1826 ret);
1827 }
1828 }
1829 }
1830
1831 chip_err(gc, "%s unknown fwnode type proceed anyway\n", __func__);
1832
1833 return;
1834}
1835
1836static int gpiochip_hierarchy_irq_domain_translate(struct irq_domain *d,
1837 struct irq_fwspec *fwspec,
1838 unsigned long *hwirq,
1839 unsigned int *type)
1840{
1841 /* We support standard DT translation */
1842 if (is_of_node(fwspec->fwnode) && fwspec->param_count == 2) {
1843 return irq_domain_translate_twocell(d, fwspec, hwirq, type);
1844 }
1845
1846 /* This is for board files and others not using DT */
1847 if (is_fwnode_irqchip(fwspec->fwnode)) {
1848 int ret;
1849
1850 ret = irq_domain_translate_twocell(d, fwspec, hwirq, type);
1851 if (ret)
1852 return ret;
1853 WARN_ON(*type == IRQ_TYPE_NONE);
1854 return 0;
1855 }
1856 return -EINVAL;
1857}
1858
1859static int gpiochip_hierarchy_irq_domain_alloc(struct irq_domain *d,
1860 unsigned int irq,
1861 unsigned int nr_irqs,
1862 void *data)
1863{
1864 struct gpio_chip *gc = d->host_data;
1865 irq_hw_number_t hwirq;
1866 unsigned int type = IRQ_TYPE_NONE;
1867 struct irq_fwspec *fwspec = data;
1868 struct irq_fwspec parent_fwspec;
1869 unsigned int parent_hwirq;
1870 unsigned int parent_type;
1871 struct gpio_irq_chip *girq = &gc->irq;
1872 int ret;
1873
1874 /*
1875 * The nr_irqs parameter is always one except for PCI multi-MSI
1876 * so this should not happen.
1877 */
1878 WARN_ON(nr_irqs != 1);
1879
1880 ret = gc->irq.child_irq_domain_ops.translate(d, fwspec, &hwirq, &type);
1881 if (ret)
1882 return ret;
1883
1884 chip_info(gc, "allocate IRQ %d, hwirq %lu\n", irq, hwirq);
1885
1886 ret = girq->child_to_parent_hwirq(gc, hwirq, type,
1887 &parent_hwirq, &parent_type);
1888 if (ret) {
1889 chip_err(gc, "can't look up hwirq %lu\n", hwirq);
1890 return ret;
1891 }
1892 chip_info(gc, "found parent hwirq %u\n", parent_hwirq);
1893
1894 /*
1895 * We set handle_bad_irq because the .set_type() should
1896 * always be invoked and set the right type of handler.
1897 */
1898 irq_domain_set_info(d,
1899 irq,
1900 hwirq,
1901 gc->irq.chip,
1902 gc,
1903 girq->handler,
1904 NULL, NULL);
1905 irq_set_probe(irq);
1906
1907 /*
1908 * Create a IRQ fwspec to send up to the parent irqdomain:
1909 * specify the hwirq we address on the parent and tie it
1910 * all together up the chain.
1911 */
1912 parent_fwspec.fwnode = d->parent->fwnode;
1913 /* This parent only handles asserted level IRQs */
1914 girq->populate_parent_fwspec(gc, &parent_fwspec, parent_hwirq,
1915 parent_type);
1916 chip_info(gc, "alloc_irqs_parent for %d parent hwirq %d\n",
1917 irq, parent_hwirq);
1918 ret = irq_domain_alloc_irqs_parent(d, irq, 1, &parent_fwspec);
1919 if (ret)
1920 chip_err(gc,
1921 "failed to allocate parent hwirq %d for hwirq %lu\n",
1922 parent_hwirq, hwirq);
1923
1924 return ret;
1925}
1926
1927static unsigned int gpiochip_child_offset_to_irq_noop(struct gpio_chip *chip,
1928 unsigned int offset)
1929{
1930 return offset;
1931}
1932
1933static void gpiochip_hierarchy_setup_domain_ops(struct irq_domain_ops *ops)
1934{
1935 ops->activate = gpiochip_irq_domain_activate;
1936 ops->deactivate = gpiochip_irq_domain_deactivate;
1937 ops->alloc = gpiochip_hierarchy_irq_domain_alloc;
1938 ops->free = irq_domain_free_irqs_common;
1939
1940 /*
1941 * We only allow overriding the translate() function for
1942 * hierarchical chips, and this should only be done if the user
1943 * really need something other than 1:1 translation.
1944 */
1945 if (!ops->translate)
1946 ops->translate = gpiochip_hierarchy_irq_domain_translate;
1947}
1948
1949static int gpiochip_hierarchy_add_domain(struct gpio_chip *gc)
1950{
1951 if (!gc->irq.child_to_parent_hwirq ||
1952 !gc->irq.fwnode) {
1953 chip_err(gc, "missing irqdomain vital data\n");
1954 return -EINVAL;
1955 }
1956
1957 if (!gc->irq.child_offset_to_irq)
1958 gc->irq.child_offset_to_irq = gpiochip_child_offset_to_irq_noop;
1959
1960 if (!gc->irq.populate_parent_fwspec)
1961 gc->irq.populate_parent_fwspec =
1962 gpiochip_populate_parent_fwspec_twocell;
1963
1964 gpiochip_hierarchy_setup_domain_ops(&gc->irq.child_irq_domain_ops);
1965
1966 gc->irq.domain = irq_domain_create_hierarchy(
1967 gc->irq.parent_domain,
1968 0,
1969 gc->ngpio,
1970 gc->irq.fwnode,
1971 &gc->irq.child_irq_domain_ops,
1972 gc);
1973
1974 if (!gc->irq.domain)
1975 return -ENOMEM;
1976
1977 gpiochip_set_hierarchical_irqchip(gc, gc->irq.chip);
1978
1979 return 0;
1980}
1981
1982static bool gpiochip_hierarchy_is_hierarchical(struct gpio_chip *gc)
1983{
1984 return !!gc->irq.parent_domain;
1985}
1986
1987void gpiochip_populate_parent_fwspec_twocell(struct gpio_chip *chip,
1988 struct irq_fwspec *fwspec,
1989 unsigned int parent_hwirq,
1990 unsigned int parent_type)
1991{
1992 fwspec->param_count = 2;
1993 fwspec->param[0] = parent_hwirq;
1994 fwspec->param[1] = parent_type;
1995}
1996EXPORT_SYMBOL_GPL(gpiochip_populate_parent_fwspec_twocell);
1997
1998void gpiochip_populate_parent_fwspec_fourcell(struct gpio_chip *chip,
1999 struct irq_fwspec *fwspec,
2000 unsigned int parent_hwirq,
2001 unsigned int parent_type)
2002{
2003 fwspec->param_count = 4;
2004 fwspec->param[0] = 0;
2005 fwspec->param[1] = parent_hwirq;
2006 fwspec->param[2] = 0;
2007 fwspec->param[3] = parent_type;
2008}
2009EXPORT_SYMBOL_GPL(gpiochip_populate_parent_fwspec_fourcell);
2010
2011#else
2012
2013static int gpiochip_hierarchy_add_domain(struct gpio_chip *gc)
2014{
2015 return -EINVAL;
2016}
2017
2018static bool gpiochip_hierarchy_is_hierarchical(struct gpio_chip *gc)
2019{
2020 return false;
2021}
2022
2023#endif /* CONFIG_IRQ_DOMAIN_HIERARCHY */
2024
2025/**
2026 * gpiochip_irq_map() - maps an IRQ into a GPIO irqchip
2027 * @d: the irqdomain used by this irqchip
2028 * @irq: the global irq number used by this GPIO irqchip irq
2029 * @hwirq: the local IRQ/GPIO line offset on this gpiochip
2030 *
2031 * This function will set up the mapping for a certain IRQ line on a
2032 * gpiochip by assigning the gpiochip as chip data, and using the irqchip
2033 * stored inside the gpiochip.
2034 */
2035int gpiochip_irq_map(struct irq_domain *d, unsigned int irq,
2036 irq_hw_number_t hwirq)
2037{
2038 struct gpio_chip *chip = d->host_data;
2039 int ret = 0;
2040
2041 if (!gpiochip_irqchip_irq_valid(chip, hwirq))
2042 return -ENXIO;
2043
2044 irq_set_chip_data(irq, chip);
2045 /*
2046 * This lock class tells lockdep that GPIO irqs are in a different
2047 * category than their parents, so it won't report false recursion.
2048 */
2049 irq_set_lockdep_class(irq, chip->irq.lock_key, chip->irq.request_key);
2050 irq_set_chip_and_handler(irq, chip->irq.chip, chip->irq.handler);
2051 /* Chips that use nested thread handlers have them marked */
2052 if (chip->irq.threaded)
2053 irq_set_nested_thread(irq, 1);
2054 irq_set_noprobe(irq);
2055
2056 if (chip->irq.num_parents == 1)
2057 ret = irq_set_parent(irq, chip->irq.parents[0]);
2058 else if (chip->irq.map)
2059 ret = irq_set_parent(irq, chip->irq.map[hwirq]);
2060
2061 if (ret < 0)
2062 return ret;
2063
2064 /*
2065 * No set-up of the hardware will happen if IRQ_TYPE_NONE
2066 * is passed as default type.
2067 */
2068 if (chip->irq.default_type != IRQ_TYPE_NONE)
2069 irq_set_irq_type(irq, chip->irq.default_type);
2070
2071 return 0;
2072}
2073EXPORT_SYMBOL_GPL(gpiochip_irq_map);
2074
2075void gpiochip_irq_unmap(struct irq_domain *d, unsigned int irq)
2076{
2077 struct gpio_chip *chip = d->host_data;
2078
2079 if (chip->irq.threaded)
2080 irq_set_nested_thread(irq, 0);
2081 irq_set_chip_and_handler(irq, NULL, NULL);
2082 irq_set_chip_data(irq, NULL);
2083}
2084EXPORT_SYMBOL_GPL(gpiochip_irq_unmap);
2085
2086static const struct irq_domain_ops gpiochip_domain_ops = {
2087 .map = gpiochip_irq_map,
2088 .unmap = gpiochip_irq_unmap,
2089 /* Virtually all GPIO irqchips are twocell:ed */
2090 .xlate = irq_domain_xlate_twocell,
2091};
2092
2093/*
2094 * TODO: move these activate/deactivate in under the hierarchicial
2095 * irqchip implementation as static once SPMI and SSBI (all external
2096 * users) are phased over.
2097 */
2098/**
2099 * gpiochip_irq_domain_activate() - Lock a GPIO to be used as an IRQ
2100 * @domain: The IRQ domain used by this IRQ chip
2101 * @data: Outermost irq_data associated with the IRQ
2102 * @reserve: If set, only reserve an interrupt vector instead of assigning one
2103 *
2104 * This function is a wrapper that calls gpiochip_lock_as_irq() and is to be
2105 * used as the activate function for the &struct irq_domain_ops. The host_data
2106 * for the IRQ domain must be the &struct gpio_chip.
2107 */
2108int gpiochip_irq_domain_activate(struct irq_domain *domain,
2109 struct irq_data *data, bool reserve)
2110{
2111 struct gpio_chip *chip = domain->host_data;
2112
2113 return gpiochip_lock_as_irq(chip, data->hwirq);
2114}
2115EXPORT_SYMBOL_GPL(gpiochip_irq_domain_activate);
2116
2117/**
2118 * gpiochip_irq_domain_deactivate() - Unlock a GPIO used as an IRQ
2119 * @domain: The IRQ domain used by this IRQ chip
2120 * @data: Outermost irq_data associated with the IRQ
2121 *
2122 * This function is a wrapper that will call gpiochip_unlock_as_irq() and is to
2123 * be used as the deactivate function for the &struct irq_domain_ops. The
2124 * host_data for the IRQ domain must be the &struct gpio_chip.
2125 */
2126void gpiochip_irq_domain_deactivate(struct irq_domain *domain,
2127 struct irq_data *data)
2128{
2129 struct gpio_chip *chip = domain->host_data;
2130
2131 return gpiochip_unlock_as_irq(chip, data->hwirq);
2132}
2133EXPORT_SYMBOL_GPL(gpiochip_irq_domain_deactivate);
2134
2135static int gpiochip_to_irq(struct gpio_chip *chip, unsigned offset)
2136{
2137 struct irq_domain *domain = chip->irq.domain;
2138
2139 if (!gpiochip_irqchip_irq_valid(chip, offset))
2140 return -ENXIO;
2141
2142#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
2143 if (irq_domain_is_hierarchy(domain)) {
2144 struct irq_fwspec spec;
2145
2146 spec.fwnode = domain->fwnode;
2147 spec.param_count = 2;
2148 spec.param[0] = chip->irq.child_offset_to_irq(chip, offset);
2149 spec.param[1] = IRQ_TYPE_NONE;
2150
2151 return irq_create_fwspec_mapping(&spec);
2152 }
2153#endif
2154
2155 return irq_create_mapping(domain, offset);
2156}
2157
2158static int gpiochip_irq_reqres(struct irq_data *d)
2159{
2160 struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
2161
2162 return gpiochip_reqres_irq(chip, d->hwirq);
2163}
2164
2165static void gpiochip_irq_relres(struct irq_data *d)
2166{
2167 struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
2168
2169 gpiochip_relres_irq(chip, d->hwirq);
2170}
2171
2172static void gpiochip_irq_enable(struct irq_data *d)
2173{
2174 struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
2175
2176 gpiochip_enable_irq(chip, d->hwirq);
2177 if (chip->irq.irq_enable)
2178 chip->irq.irq_enable(d);
2179 else
2180 chip->irq.chip->irq_unmask(d);
2181}
2182
2183static void gpiochip_irq_disable(struct irq_data *d)
2184{
2185 struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
2186
2187 if (chip->irq.irq_disable)
2188 chip->irq.irq_disable(d);
2189 else
2190 chip->irq.chip->irq_mask(d);
2191 gpiochip_disable_irq(chip, d->hwirq);
2192}
2193
2194static void gpiochip_set_irq_hooks(struct gpio_chip *gpiochip)
2195{
2196 struct irq_chip *irqchip = gpiochip->irq.chip;
2197
2198 if (!irqchip->irq_request_resources &&
2199 !irqchip->irq_release_resources) {
2200 irqchip->irq_request_resources = gpiochip_irq_reqres;
2201 irqchip->irq_release_resources = gpiochip_irq_relres;
2202 }
2203 if (WARN_ON(gpiochip->irq.irq_enable))
2204 return;
2205 /* Check if the irqchip already has this hook... */
2206 if (irqchip->irq_enable == gpiochip_irq_enable) {
2207 /*
2208 * ...and if so, give a gentle warning that this is bad
2209 * practice.
2210 */
2211 chip_info(gpiochip,
2212 "detected irqchip that is shared with multiple gpiochips: please fix the driver.\n");
2213 return;
2214 }
2215 gpiochip->irq.irq_enable = irqchip->irq_enable;
2216 gpiochip->irq.irq_disable = irqchip->irq_disable;
2217 irqchip->irq_enable = gpiochip_irq_enable;
2218 irqchip->irq_disable = gpiochip_irq_disable;
2219}
2220
2221/**
2222 * gpiochip_add_irqchip() - adds an IRQ chip to a GPIO chip
2223 * @gpiochip: the GPIO chip to add the IRQ chip to
2224 * @lock_key: lockdep class for IRQ lock
2225 * @request_key: lockdep class for IRQ request
2226 */
2227static int gpiochip_add_irqchip(struct gpio_chip *gpiochip,
2228 struct lock_class_key *lock_key,
2229 struct lock_class_key *request_key)
2230{
2231 struct irq_chip *irqchip = gpiochip->irq.chip;
2232 const struct irq_domain_ops *ops = NULL;
2233 struct device_node *np;
2234 unsigned int type;
2235 unsigned int i;
2236
2237 if (!irqchip)
2238 return 0;
2239
2240 if (gpiochip->irq.parent_handler && gpiochip->can_sleep) {
2241 chip_err(gpiochip, "you cannot have chained interrupts on a chip that may sleep\n");
2242 return -EINVAL;
2243 }
2244
2245 np = gpiochip->gpiodev->dev.of_node;
2246 type = gpiochip->irq.default_type;
2247
2248 /*
2249 * Specifying a default trigger is a terrible idea if DT or ACPI is
2250 * used to configure the interrupts, as you may end up with
2251 * conflicting triggers. Tell the user, and reset to NONE.
2252 */
2253 if (WARN(np && type != IRQ_TYPE_NONE,
2254 "%s: Ignoring %u default trigger\n", np->full_name, type))
2255 type = IRQ_TYPE_NONE;
2256
2257 if (has_acpi_companion(gpiochip->parent) && type != IRQ_TYPE_NONE) {
2258 acpi_handle_warn(ACPI_HANDLE(gpiochip->parent),
2259 "Ignoring %u default trigger\n", type);
2260 type = IRQ_TYPE_NONE;
2261 }
2262
2263 gpiochip->to_irq = gpiochip_to_irq;
2264 gpiochip->irq.default_type = type;
2265 gpiochip->irq.lock_key = lock_key;
2266 gpiochip->irq.request_key = request_key;
2267
2268 /* If a parent irqdomain is provided, let's build a hierarchy */
2269 if (gpiochip_hierarchy_is_hierarchical(gpiochip)) {
2270 int ret = gpiochip_hierarchy_add_domain(gpiochip);
2271 if (ret)
2272 return ret;
2273 } else {
2274 /* Some drivers provide custom irqdomain ops */
2275 if (gpiochip->irq.domain_ops)
2276 ops = gpiochip->irq.domain_ops;
2277
2278 if (!ops)
2279 ops = &gpiochip_domain_ops;
2280 gpiochip->irq.domain = irq_domain_add_simple(np,
2281 gpiochip->ngpio,
2282 gpiochip->irq.first,
2283 ops, gpiochip);
2284 if (!gpiochip->irq.domain)
2285 return -EINVAL;
2286 }
2287
2288 if (gpiochip->irq.parent_handler) {
2289 void *data = gpiochip->irq.parent_handler_data ?: gpiochip;
2290
2291 for (i = 0; i < gpiochip->irq.num_parents; i++) {
2292 /*
2293 * The parent IRQ chip is already using the chip_data
2294 * for this IRQ chip, so our callbacks simply use the
2295 * handler_data.
2296 */
2297 irq_set_chained_handler_and_data(gpiochip->irq.parents[i],
2298 gpiochip->irq.parent_handler,
2299 data);
2300 }
2301 }
2302
2303 gpiochip_set_irq_hooks(gpiochip);
2304
2305 acpi_gpiochip_request_interrupts(gpiochip);
2306
2307 return 0;
2308}
2309
2310/**
2311 * gpiochip_irqchip_remove() - removes an irqchip added to a gpiochip
2312 * @gpiochip: the gpiochip to remove the irqchip from
2313 *
2314 * This is called only from gpiochip_remove()
2315 */
2316static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip)
2317{
2318 struct irq_chip *irqchip = gpiochip->irq.chip;
2319 unsigned int offset;
2320
2321 acpi_gpiochip_free_interrupts(gpiochip);
2322
2323 if (irqchip && gpiochip->irq.parent_handler) {
2324 struct gpio_irq_chip *irq = &gpiochip->irq;
2325 unsigned int i;
2326
2327 for (i = 0; i < irq->num_parents; i++)
2328 irq_set_chained_handler_and_data(irq->parents[i],
2329 NULL, NULL);
2330 }
2331
2332 /* Remove all IRQ mappings and delete the domain */
2333 if (gpiochip->irq.domain) {
2334 unsigned int irq;
2335
2336 for (offset = 0; offset < gpiochip->ngpio; offset++) {
2337 if (!gpiochip_irqchip_irq_valid(gpiochip, offset))
2338 continue;
2339
2340 irq = irq_find_mapping(gpiochip->irq.domain, offset);
2341 irq_dispose_mapping(irq);
2342 }
2343
2344 irq_domain_remove(gpiochip->irq.domain);
2345 }
2346
2347 if (irqchip) {
2348 if (irqchip->irq_request_resources == gpiochip_irq_reqres) {
2349 irqchip->irq_request_resources = NULL;
2350 irqchip->irq_release_resources = NULL;
2351 }
2352 if (irqchip->irq_enable == gpiochip_irq_enable) {
2353 irqchip->irq_enable = gpiochip->irq.irq_enable;
2354 irqchip->irq_disable = gpiochip->irq.irq_disable;
2355 }
2356 }
2357 gpiochip->irq.irq_enable = NULL;
2358 gpiochip->irq.irq_disable = NULL;
2359 gpiochip->irq.chip = NULL;
2360
2361 gpiochip_irqchip_free_valid_mask(gpiochip);
2362}
2363
2364/**
2365 * gpiochip_irqchip_add_key() - adds an irqchip to a gpiochip
2366 * @gpiochip: the gpiochip to add the irqchip to
2367 * @irqchip: the irqchip to add to the gpiochip
2368 * @first_irq: if not dynamically assigned, the base (first) IRQ to
2369 * allocate gpiochip irqs from
2370 * @handler: the irq handler to use (often a predefined irq core function)
2371 * @type: the default type for IRQs on this irqchip, pass IRQ_TYPE_NONE
2372 * to have the core avoid setting up any default type in the hardware.
2373 * @threaded: whether this irqchip uses a nested thread handler
2374 * @lock_key: lockdep class for IRQ lock
2375 * @request_key: lockdep class for IRQ request
2376 *
2377 * This function closely associates a certain irqchip with a certain
2378 * gpiochip, providing an irq domain to translate the local IRQs to
2379 * global irqs in the gpiolib core, and making sure that the gpiochip
2380 * is passed as chip data to all related functions. Driver callbacks
2381 * need to use gpiochip_get_data() to get their local state containers back
2382 * from the gpiochip passed as chip data. An irqdomain will be stored
2383 * in the gpiochip that shall be used by the driver to handle IRQ number
2384 * translation. The gpiochip will need to be initialized and registered
2385 * before calling this function.
2386 *
2387 * This function will handle two cell:ed simple IRQs and assumes all
2388 * the pins on the gpiochip can generate a unique IRQ. Everything else
2389 * need to be open coded.
2390 */
2391int gpiochip_irqchip_add_key(struct gpio_chip *gpiochip,
2392 struct irq_chip *irqchip,
2393 unsigned int first_irq,
2394 irq_flow_handler_t handler,
2395 unsigned int type,
2396 bool threaded,
2397 struct lock_class_key *lock_key,
2398 struct lock_class_key *request_key)
2399{
2400 struct device_node *of_node;
2401
2402 if (!gpiochip || !irqchip)
2403 return -EINVAL;
2404
2405 if (!gpiochip->parent) {
2406 pr_err("missing gpiochip .dev parent pointer\n");
2407 return -EINVAL;
2408 }
2409 gpiochip->irq.threaded = threaded;
2410 of_node = gpiochip->parent->of_node;
2411#ifdef CONFIG_OF_GPIO
2412 /*
2413 * If the gpiochip has an assigned OF node this takes precedence
2414 * FIXME: get rid of this and use gpiochip->parent->of_node
2415 * everywhere
2416 */
2417 if (gpiochip->of_node)
2418 of_node = gpiochip->of_node;
2419#endif
2420 /*
2421 * Specifying a default trigger is a terrible idea if DT or ACPI is
2422 * used to configure the interrupts, as you may end-up with
2423 * conflicting triggers. Tell the user, and reset to NONE.
2424 */
2425 if (WARN(of_node && type != IRQ_TYPE_NONE,
2426 "%pOF: Ignoring %d default trigger\n", of_node, type))
2427 type = IRQ_TYPE_NONE;
2428 if (has_acpi_companion(gpiochip->parent) && type != IRQ_TYPE_NONE) {
2429 acpi_handle_warn(ACPI_HANDLE(gpiochip->parent),
2430 "Ignoring %d default trigger\n", type);
2431 type = IRQ_TYPE_NONE;
2432 }
2433
2434 gpiochip->irq.chip = irqchip;
2435 gpiochip->irq.handler = handler;
2436 gpiochip->irq.default_type = type;
2437 gpiochip->to_irq = gpiochip_to_irq;
2438 gpiochip->irq.lock_key = lock_key;
2439 gpiochip->irq.request_key = request_key;
2440 gpiochip->irq.domain = irq_domain_add_simple(of_node,
2441 gpiochip->ngpio, first_irq,
2442 &gpiochip_domain_ops, gpiochip);
2443 if (!gpiochip->irq.domain) {
2444 gpiochip->irq.chip = NULL;
2445 return -EINVAL;
2446 }
2447
2448 gpiochip_set_irq_hooks(gpiochip);
2449
2450 acpi_gpiochip_request_interrupts(gpiochip);
2451
2452 return 0;
2453}
2454EXPORT_SYMBOL_GPL(gpiochip_irqchip_add_key);
2455
2456#else /* CONFIG_GPIOLIB_IRQCHIP */
2457
2458static inline int gpiochip_add_irqchip(struct gpio_chip *gpiochip,
2459 struct lock_class_key *lock_key,
2460 struct lock_class_key *request_key)
2461{
2462 return 0;
2463}
2464static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip) {}
2465
2466static inline int gpiochip_irqchip_init_hw(struct gpio_chip *gpiochip)
2467{
2468 return 0;
2469}
2470
2471static inline int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gpiochip)
2472{
2473 return 0;
2474}
2475static inline void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gpiochip)
2476{ }
2477
2478#endif /* CONFIG_GPIOLIB_IRQCHIP */
2479
2480/**
2481 * gpiochip_generic_request() - request the gpio function for a pin
2482 * @chip: the gpiochip owning the GPIO
2483 * @offset: the offset of the GPIO to request for GPIO function
2484 */
2485int gpiochip_generic_request(struct gpio_chip *chip, unsigned offset)
2486{
2487 return pinctrl_gpio_request(chip->gpiodev->base + offset);
2488}
2489EXPORT_SYMBOL_GPL(gpiochip_generic_request);
2490
2491/**
2492 * gpiochip_generic_free() - free the gpio function from a pin
2493 * @chip: the gpiochip to request the gpio function for
2494 * @offset: the offset of the GPIO to free from GPIO function
2495 */
2496void gpiochip_generic_free(struct gpio_chip *chip, unsigned offset)
2497{
2498 pinctrl_gpio_free(chip->gpiodev->base + offset);
2499}
2500EXPORT_SYMBOL_GPL(gpiochip_generic_free);
2501
2502/**
2503 * gpiochip_generic_config() - apply configuration for a pin
2504 * @chip: the gpiochip owning the GPIO
2505 * @offset: the offset of the GPIO to apply the configuration
2506 * @config: the configuration to be applied
2507 */
2508int gpiochip_generic_config(struct gpio_chip *chip, unsigned offset,
2509 unsigned long config)
2510{
2511 return pinctrl_gpio_set_config(chip->gpiodev->base + offset, config);
2512}
2513EXPORT_SYMBOL_GPL(gpiochip_generic_config);
2514
2515#ifdef CONFIG_PINCTRL
2516
2517/**
2518 * gpiochip_add_pingroup_range() - add a range for GPIO <-> pin mapping
2519 * @chip: the gpiochip to add the range for
2520 * @pctldev: the pin controller to map to
2521 * @gpio_offset: the start offset in the current gpio_chip number space
2522 * @pin_group: name of the pin group inside the pin controller
2523 *
2524 * Calling this function directly from a DeviceTree-supported
2525 * pinctrl driver is DEPRECATED. Please see Section 2.1 of
2526 * Documentation/devicetree/bindings/gpio/gpio.txt on how to
2527 * bind pinctrl and gpio drivers via the "gpio-ranges" property.
2528 */
2529int gpiochip_add_pingroup_range(struct gpio_chip *chip,
2530 struct pinctrl_dev *pctldev,
2531 unsigned int gpio_offset, const char *pin_group)
2532{
2533 struct gpio_pin_range *pin_range;
2534 struct gpio_device *gdev = chip->gpiodev;
2535 int ret;
2536
2537 pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL);
2538 if (!pin_range) {
2539 chip_err(chip, "failed to allocate pin ranges\n");
2540 return -ENOMEM;
2541 }
2542
2543 /* Use local offset as range ID */
2544 pin_range->range.id = gpio_offset;
2545 pin_range->range.gc = chip;
2546 pin_range->range.name = chip->label;
2547 pin_range->range.base = gdev->base + gpio_offset;
2548 pin_range->pctldev = pctldev;
2549
2550 ret = pinctrl_get_group_pins(pctldev, pin_group,
2551 &pin_range->range.pins,
2552 &pin_range->range.npins);
2553 if (ret < 0) {
2554 kfree(pin_range);
2555 return ret;
2556 }
2557
2558 pinctrl_add_gpio_range(pctldev, &pin_range->range);
2559
2560 chip_dbg(chip, "created GPIO range %d->%d ==> %s PINGRP %s\n",
2561 gpio_offset, gpio_offset + pin_range->range.npins - 1,
2562 pinctrl_dev_get_devname(pctldev), pin_group);
2563
2564 list_add_tail(&pin_range->node, &gdev->pin_ranges);
2565
2566 return 0;
2567}
2568EXPORT_SYMBOL_GPL(gpiochip_add_pingroup_range);
2569
2570/**
2571 * gpiochip_add_pin_range() - add a range for GPIO <-> pin mapping
2572 * @chip: the gpiochip to add the range for
2573 * @pinctl_name: the dev_name() of the pin controller to map to
2574 * @gpio_offset: the start offset in the current gpio_chip number space
2575 * @pin_offset: the start offset in the pin controller number space
2576 * @npins: the number of pins from the offset of each pin space (GPIO and
2577 * pin controller) to accumulate in this range
2578 *
2579 * Returns:
2580 * 0 on success, or a negative error-code on failure.
2581 *
2582 * Calling this function directly from a DeviceTree-supported
2583 * pinctrl driver is DEPRECATED. Please see Section 2.1 of
2584 * Documentation/devicetree/bindings/gpio/gpio.txt on how to
2585 * bind pinctrl and gpio drivers via the "gpio-ranges" property.
2586 */
2587int gpiochip_add_pin_range(struct gpio_chip *chip, const char *pinctl_name,
2588 unsigned int gpio_offset, unsigned int pin_offset,
2589 unsigned int npins)
2590{
2591 struct gpio_pin_range *pin_range;
2592 struct gpio_device *gdev = chip->gpiodev;
2593 int ret;
2594
2595 pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL);
2596 if (!pin_range) {
2597 chip_err(chip, "failed to allocate pin ranges\n");
2598 return -ENOMEM;
2599 }
2600
2601 /* Use local offset as range ID */
2602 pin_range->range.id = gpio_offset;
2603 pin_range->range.gc = chip;
2604 pin_range->range.name = chip->label;
2605 pin_range->range.base = gdev->base + gpio_offset;
2606 pin_range->range.pin_base = pin_offset;
2607 pin_range->range.npins = npins;
2608 pin_range->pctldev = pinctrl_find_and_add_gpio_range(pinctl_name,
2609 &pin_range->range);
2610 if (IS_ERR(pin_range->pctldev)) {
2611 ret = PTR_ERR(pin_range->pctldev);
2612 chip_err(chip, "could not create pin range\n");
2613 kfree(pin_range);
2614 return ret;
2615 }
2616 chip_dbg(chip, "created GPIO range %d->%d ==> %s PIN %d->%d\n",
2617 gpio_offset, gpio_offset + npins - 1,
2618 pinctl_name,
2619 pin_offset, pin_offset + npins - 1);
2620
2621 list_add_tail(&pin_range->node, &gdev->pin_ranges);
2622
2623 return 0;
2624}
2625EXPORT_SYMBOL_GPL(gpiochip_add_pin_range);
2626
2627/**
2628 * gpiochip_remove_pin_ranges() - remove all the GPIO <-> pin mappings
2629 * @chip: the chip to remove all the mappings for
2630 */
2631void gpiochip_remove_pin_ranges(struct gpio_chip *chip)
2632{
2633 struct gpio_pin_range *pin_range, *tmp;
2634 struct gpio_device *gdev = chip->gpiodev;
2635
2636 list_for_each_entry_safe(pin_range, tmp, &gdev->pin_ranges, node) {
2637 list_del(&pin_range->node);
2638 pinctrl_remove_gpio_range(pin_range->pctldev,
2639 &pin_range->range);
2640 kfree(pin_range);
2641 }
2642}
2643EXPORT_SYMBOL_GPL(gpiochip_remove_pin_ranges);
2644
2645#endif /* CONFIG_PINCTRL */
2646
2647/* These "optional" allocation calls help prevent drivers from stomping
2648 * on each other, and help provide better diagnostics in debugfs.
2649 * They're called even less than the "set direction" calls.
2650 */
2651static int gpiod_request_commit(struct gpio_desc *desc, const char *label)
2652{
2653 struct gpio_chip *chip = desc->gdev->chip;
2654 int ret;
2655 unsigned long flags;
2656 unsigned offset;
2657
2658 if (label) {
2659 label = kstrdup_const(label, GFP_KERNEL);
2660 if (!label)
2661 return -ENOMEM;
2662 }
2663
2664 spin_lock_irqsave(&gpio_lock, flags);
2665
2666 /* NOTE: gpio_request() can be called in early boot,
2667 * before IRQs are enabled, for non-sleeping (SOC) GPIOs.
2668 */
2669
2670 if (test_and_set_bit(FLAG_REQUESTED, &desc->flags) == 0) {
2671 desc_set_label(desc, label ? : "?");
2672 ret = 0;
2673 } else {
2674 kfree_const(label);
2675 ret = -EBUSY;
2676 goto done;
2677 }
2678
2679 if (chip->request) {
2680 /* chip->request may sleep */
2681 spin_unlock_irqrestore(&gpio_lock, flags);
2682 offset = gpio_chip_hwgpio(desc);
2683 if (gpiochip_line_is_valid(chip, offset))
2684 ret = chip->request(chip, offset);
2685 else
2686 ret = -EINVAL;
2687 spin_lock_irqsave(&gpio_lock, flags);
2688
2689 if (ret < 0) {
2690 desc_set_label(desc, NULL);
2691 kfree_const(label);
2692 clear_bit(FLAG_REQUESTED, &desc->flags);
2693 goto done;
2694 }
2695 }
2696 if (chip->get_direction) {
2697 /* chip->get_direction may sleep */
2698 spin_unlock_irqrestore(&gpio_lock, flags);
2699 gpiod_get_direction(desc);
2700 spin_lock_irqsave(&gpio_lock, flags);
2701 }
2702done:
2703 spin_unlock_irqrestore(&gpio_lock, flags);
2704 return ret;
2705}
2706
2707/*
2708 * This descriptor validation needs to be inserted verbatim into each
2709 * function taking a descriptor, so we need to use a preprocessor
2710 * macro to avoid endless duplication. If the desc is NULL it is an
2711 * optional GPIO and calls should just bail out.
2712 */
2713static int validate_desc(const struct gpio_desc *desc, const char *func)
2714{
2715 if (!desc)
2716 return 0;
2717 if (IS_ERR(desc)) {
2718 pr_warn("%s: invalid GPIO (errorpointer)\n", func);
2719 return PTR_ERR(desc);
2720 }
2721 if (!desc->gdev) {
2722 pr_warn("%s: invalid GPIO (no device)\n", func);
2723 return -EINVAL;
2724 }
2725 if (!desc->gdev->chip) {
2726 dev_warn(&desc->gdev->dev,
2727 "%s: backing chip is gone\n", func);
2728 return 0;
2729 }
2730 return 1;
2731}
2732
2733#define VALIDATE_DESC(desc) do { \
2734 int __valid = validate_desc(desc, __func__); \
2735 if (__valid <= 0) \
2736 return __valid; \
2737 } while (0)
2738
2739#define VALIDATE_DESC_VOID(desc) do { \
2740 int __valid = validate_desc(desc, __func__); \
2741 if (__valid <= 0) \
2742 return; \
2743 } while (0)
2744
2745int gpiod_request(struct gpio_desc *desc, const char *label)
2746{
2747 int ret = -EPROBE_DEFER;
2748 struct gpio_device *gdev;
2749
2750 VALIDATE_DESC(desc);
2751 gdev = desc->gdev;
2752
2753 if (try_module_get(gdev->owner)) {
2754 ret = gpiod_request_commit(desc, label);
2755 if (ret < 0)
2756 module_put(gdev->owner);
2757 else
2758 get_device(&gdev->dev);
2759 }
2760
2761 if (ret)
2762 gpiod_dbg(desc, "%s: status %d\n", __func__, ret);
2763
2764 return ret;
2765}
2766
2767static bool gpiod_free_commit(struct gpio_desc *desc)
2768{
2769 bool ret = false;
2770 unsigned long flags;
2771 struct gpio_chip *chip;
2772
2773 might_sleep();
2774
2775 gpiod_unexport(desc);
2776
2777 spin_lock_irqsave(&gpio_lock, flags);
2778
2779 chip = desc->gdev->chip;
2780 if (chip && test_bit(FLAG_REQUESTED, &desc->flags)) {
2781 if (chip->free) {
2782 spin_unlock_irqrestore(&gpio_lock, flags);
2783 might_sleep_if(chip->can_sleep);
2784 chip->free(chip, gpio_chip_hwgpio(desc));
2785 spin_lock_irqsave(&gpio_lock, flags);
2786 }
2787 kfree_const(desc->label);
2788 desc_set_label(desc, NULL);
2789 clear_bit(FLAG_ACTIVE_LOW, &desc->flags);
2790 clear_bit(FLAG_REQUESTED, &desc->flags);
2791 clear_bit(FLAG_OPEN_DRAIN, &desc->flags);
2792 clear_bit(FLAG_OPEN_SOURCE, &desc->flags);
2793 clear_bit(FLAG_IS_HOGGED, &desc->flags);
2794 ret = true;
2795 }
2796
2797 spin_unlock_irqrestore(&gpio_lock, flags);
2798 return ret;
2799}
2800
2801void gpiod_free(struct gpio_desc *desc)
2802{
2803 if (desc && desc->gdev && gpiod_free_commit(desc)) {
2804 module_put(desc->gdev->owner);
2805 put_device(&desc->gdev->dev);
2806 } else {
2807 WARN_ON(extra_checks);
2808 }
2809}
2810
2811/**
2812 * gpiochip_is_requested - return string iff signal was requested
2813 * @chip: controller managing the signal
2814 * @offset: of signal within controller's 0..(ngpio - 1) range
2815 *
2816 * Returns NULL if the GPIO is not currently requested, else a string.
2817 * The string returned is the label passed to gpio_request(); if none has been
2818 * passed it is a meaningless, non-NULL constant.
2819 *
2820 * This function is for use by GPIO controller drivers. The label can
2821 * help with diagnostics, and knowing that the signal is used as a GPIO
2822 * can help avoid accidentally multiplexing it to another controller.
2823 */
2824const char *gpiochip_is_requested(struct gpio_chip *chip, unsigned offset)
2825{
2826 struct gpio_desc *desc;
2827
2828 if (offset >= chip->ngpio)
2829 return NULL;
2830
2831 desc = &chip->gpiodev->descs[offset];
2832
2833 if (test_bit(FLAG_REQUESTED, &desc->flags) == 0)
2834 return NULL;
2835 return desc->label;
2836}
2837EXPORT_SYMBOL_GPL(gpiochip_is_requested);
2838
2839/**
2840 * gpiochip_request_own_desc - Allow GPIO chip to request its own descriptor
2841 * @chip: GPIO chip
2842 * @hwnum: hardware number of the GPIO for which to request the descriptor
2843 * @label: label for the GPIO
2844 * @lflags: lookup flags for this GPIO or 0 if default, this can be used to
2845 * specify things like line inversion semantics with the machine flags
2846 * such as GPIO_OUT_LOW
2847 * @dflags: descriptor request flags for this GPIO or 0 if default, this
2848 * can be used to specify consumer semantics such as open drain
2849 *
2850 * Function allows GPIO chip drivers to request and use their own GPIO
2851 * descriptors via gpiolib API. Difference to gpiod_request() is that this
2852 * function will not increase reference count of the GPIO chip module. This
2853 * allows the GPIO chip module to be unloaded as needed (we assume that the
2854 * GPIO chip driver handles freeing the GPIOs it has requested).
2855 *
2856 * Returns:
2857 * A pointer to the GPIO descriptor, or an ERR_PTR()-encoded negative error
2858 * code on failure.
2859 */
2860struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *chip, u16 hwnum,
2861 const char *label,
2862 enum gpio_lookup_flags lflags,
2863 enum gpiod_flags dflags)
2864{
2865 struct gpio_desc *desc = gpiochip_get_desc(chip, hwnum);
2866 int ret;
2867
2868 if (IS_ERR(desc)) {
2869 chip_err(chip, "failed to get GPIO descriptor\n");
2870 return desc;
2871 }
2872
2873 ret = gpiod_request_commit(desc, label);
2874 if (ret < 0)
2875 return ERR_PTR(ret);
2876
2877 ret = gpiod_configure_flags(desc, label, lflags, dflags);
2878 if (ret) {
2879 chip_err(chip, "setup of own GPIO %s failed\n", label);
2880 gpiod_free_commit(desc);
2881 return ERR_PTR(ret);
2882 }
2883
2884 return desc;
2885}
2886EXPORT_SYMBOL_GPL(gpiochip_request_own_desc);
2887
2888/**
2889 * gpiochip_free_own_desc - Free GPIO requested by the chip driver
2890 * @desc: GPIO descriptor to free
2891 *
2892 * Function frees the given GPIO requested previously with
2893 * gpiochip_request_own_desc().
2894 */
2895void gpiochip_free_own_desc(struct gpio_desc *desc)
2896{
2897 if (desc)
2898 gpiod_free_commit(desc);
2899}
2900EXPORT_SYMBOL_GPL(gpiochip_free_own_desc);
2901
2902/*
2903 * Drivers MUST set GPIO direction before making get/set calls. In
2904 * some cases this is done in early boot, before IRQs are enabled.
2905 *
2906 * As a rule these aren't called more than once (except for drivers
2907 * using the open-drain emulation idiom) so these are natural places
2908 * to accumulate extra debugging checks. Note that we can't (yet)
2909 * rely on gpio_request() having been called beforehand.
2910 */
2911
2912static int gpio_set_config(struct gpio_chip *gc, unsigned offset,
2913 enum pin_config_param mode)
2914{
2915 unsigned long config;
2916 unsigned arg;
2917
2918 switch (mode) {
2919 case PIN_CONFIG_BIAS_PULL_DOWN:
2920 case PIN_CONFIG_BIAS_PULL_UP:
2921 arg = 1;
2922 break;
2923
2924 default:
2925 arg = 0;
2926 }
2927
2928 config = PIN_CONF_PACKED(mode, arg);
2929 return gc->set_config ? gc->set_config(gc, offset, config) : -ENOTSUPP;
2930}
2931
2932/**
2933 * gpiod_direction_input - set the GPIO direction to input
2934 * @desc: GPIO to set to input
2935 *
2936 * Set the direction of the passed GPIO to input, such as gpiod_get_value() can
2937 * be called safely on it.
2938 *
2939 * Return 0 in case of success, else an error code.
2940 */
2941int gpiod_direction_input(struct gpio_desc *desc)
2942{
2943 struct gpio_chip *chip;
2944 int ret = 0;
2945
2946 VALIDATE_DESC(desc);
2947 chip = desc->gdev->chip;
2948
2949 /*
2950 * It is legal to have no .get() and .direction_input() specified if
2951 * the chip is output-only, but you can't specify .direction_input()
2952 * and not support the .get() operation, that doesn't make sense.
2953 */
2954 if (!chip->get && chip->direction_input) {
2955 gpiod_warn(desc,
2956 "%s: missing get() but have direction_input()\n",
2957 __func__);
2958 return -EIO;
2959 }
2960
2961 /*
2962 * If we have a .direction_input() callback, things are simple,
2963 * just call it. Else we are some input-only chip so try to check the
2964 * direction (if .get_direction() is supported) else we silently
2965 * assume we are in input mode after this.
2966 */
2967 if (chip->direction_input) {
2968 ret = chip->direction_input(chip, gpio_chip_hwgpio(desc));
2969 } else if (chip->get_direction &&
2970 (chip->get_direction(chip, gpio_chip_hwgpio(desc)) != 1)) {
2971 gpiod_warn(desc,
2972 "%s: missing direction_input() operation and line is output\n",
2973 __func__);
2974 return -EIO;
2975 }
2976 if (ret == 0)
2977 clear_bit(FLAG_IS_OUT, &desc->flags);
2978
2979 if (test_bit(FLAG_PULL_UP, &desc->flags))
2980 gpio_set_config(chip, gpio_chip_hwgpio(desc),
2981 PIN_CONFIG_BIAS_PULL_UP);
2982 else if (test_bit(FLAG_PULL_DOWN, &desc->flags))
2983 gpio_set_config(chip, gpio_chip_hwgpio(desc),
2984 PIN_CONFIG_BIAS_PULL_DOWN);
2985
2986 trace_gpio_direction(desc_to_gpio(desc), 1, ret);
2987
2988 return ret;
2989}
2990EXPORT_SYMBOL_GPL(gpiod_direction_input);
2991
2992static int gpiod_direction_output_raw_commit(struct gpio_desc *desc, int value)
2993{
2994 struct gpio_chip *gc = desc->gdev->chip;
2995 int val = !!value;
2996 int ret = 0;
2997
2998 /*
2999 * It's OK not to specify .direction_output() if the gpiochip is
3000 * output-only, but if there is then not even a .set() operation it
3001 * is pretty tricky to drive the output line.
3002 */
3003 if (!gc->set && !gc->direction_output) {
3004 gpiod_warn(desc,
3005 "%s: missing set() and direction_output() operations\n",
3006 __func__);
3007 return -EIO;
3008 }
3009
3010 if (gc->direction_output) {
3011 ret = gc->direction_output(gc, gpio_chip_hwgpio(desc), val);
3012 } else {
3013 /* Check that we are in output mode if we can */
3014 if (gc->get_direction &&
3015 gc->get_direction(gc, gpio_chip_hwgpio(desc))) {
3016 gpiod_warn(desc,
3017 "%s: missing direction_output() operation\n",
3018 __func__);
3019 return -EIO;
3020 }
3021 /*
3022 * If we can't actively set the direction, we are some
3023 * output-only chip, so just drive the output as desired.
3024 */
3025 gc->set(gc, gpio_chip_hwgpio(desc), val);
3026 }
3027
3028 if (!ret)
3029 set_bit(FLAG_IS_OUT, &desc->flags);
3030 trace_gpio_value(desc_to_gpio(desc), 0, val);
3031 trace_gpio_direction(desc_to_gpio(desc), 0, ret);
3032 return ret;
3033}
3034
3035/**
3036 * gpiod_direction_output_raw - set the GPIO direction to output
3037 * @desc: GPIO to set to output
3038 * @value: initial output value of the GPIO
3039 *
3040 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
3041 * be called safely on it. The initial value of the output must be specified
3042 * as raw value on the physical line without regard for the ACTIVE_LOW status.
3043 *
3044 * Return 0 in case of success, else an error code.
3045 */
3046int gpiod_direction_output_raw(struct gpio_desc *desc, int value)
3047{
3048 VALIDATE_DESC(desc);
3049 return gpiod_direction_output_raw_commit(desc, value);
3050}
3051EXPORT_SYMBOL_GPL(gpiod_direction_output_raw);
3052
3053/**
3054 * gpiod_direction_output - set the GPIO direction to output
3055 * @desc: GPIO to set to output
3056 * @value: initial output value of the GPIO
3057 *
3058 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
3059 * be called safely on it. The initial value of the output must be specified
3060 * as the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
3061 * account.
3062 *
3063 * Return 0 in case of success, else an error code.
3064 */
3065int gpiod_direction_output(struct gpio_desc *desc, int value)
3066{
3067 struct gpio_chip *gc;
3068 int ret;
3069
3070 VALIDATE_DESC(desc);
3071 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3072 value = !value;
3073 else
3074 value = !!value;
3075
3076 /* GPIOs used for enabled IRQs shall not be set as output */
3077 if (test_bit(FLAG_USED_AS_IRQ, &desc->flags) &&
3078 test_bit(FLAG_IRQ_IS_ENABLED, &desc->flags)) {
3079 gpiod_err(desc,
3080 "%s: tried to set a GPIO tied to an IRQ as output\n",
3081 __func__);
3082 return -EIO;
3083 }
3084
3085 gc = desc->gdev->chip;
3086 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) {
3087 /* First see if we can enable open drain in hardware */
3088 ret = gpio_set_config(gc, gpio_chip_hwgpio(desc),
3089 PIN_CONFIG_DRIVE_OPEN_DRAIN);
3090 if (!ret)
3091 goto set_output_value;
3092 /* Emulate open drain by not actively driving the line high */
3093 if (value) {
3094 ret = gpiod_direction_input(desc);
3095 goto set_output_flag;
3096 }
3097 }
3098 else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) {
3099 ret = gpio_set_config(gc, gpio_chip_hwgpio(desc),
3100 PIN_CONFIG_DRIVE_OPEN_SOURCE);
3101 if (!ret)
3102 goto set_output_value;
3103 /* Emulate open source by not actively driving the line low */
3104 if (!value) {
3105 ret = gpiod_direction_input(desc);
3106 goto set_output_flag;
3107 }
3108 } else {
3109 gpio_set_config(gc, gpio_chip_hwgpio(desc),
3110 PIN_CONFIG_DRIVE_PUSH_PULL);
3111 }
3112
3113set_output_value:
3114 return gpiod_direction_output_raw_commit(desc, value);
3115
3116set_output_flag:
3117 /*
3118 * When emulating open-source or open-drain functionalities by not
3119 * actively driving the line (setting mode to input) we still need to
3120 * set the IS_OUT flag or otherwise we won't be able to set the line
3121 * value anymore.
3122 */
3123 if (ret == 0)
3124 set_bit(FLAG_IS_OUT, &desc->flags);
3125 return ret;
3126}
3127EXPORT_SYMBOL_GPL(gpiod_direction_output);
3128
3129/**
3130 * gpiod_set_debounce - sets @debounce time for a GPIO
3131 * @desc: descriptor of the GPIO for which to set debounce time
3132 * @debounce: debounce time in microseconds
3133 *
3134 * Returns:
3135 * 0 on success, %-ENOTSUPP if the controller doesn't support setting the
3136 * debounce time.
3137 */
3138int gpiod_set_debounce(struct gpio_desc *desc, unsigned debounce)
3139{
3140 struct gpio_chip *chip;
3141 unsigned long config;
3142
3143 VALIDATE_DESC(desc);
3144 chip = desc->gdev->chip;
3145 if (!chip->set || !chip->set_config) {
3146 gpiod_dbg(desc,
3147 "%s: missing set() or set_config() operations\n",
3148 __func__);
3149 return -ENOTSUPP;
3150 }
3151
3152 config = pinconf_to_config_packed(PIN_CONFIG_INPUT_DEBOUNCE, debounce);
3153 return chip->set_config(chip, gpio_chip_hwgpio(desc), config);
3154}
3155EXPORT_SYMBOL_GPL(gpiod_set_debounce);
3156
3157/**
3158 * gpiod_set_transitory - Lose or retain GPIO state on suspend or reset
3159 * @desc: descriptor of the GPIO for which to configure persistence
3160 * @transitory: True to lose state on suspend or reset, false for persistence
3161 *
3162 * Returns:
3163 * 0 on success, otherwise a negative error code.
3164 */
3165int gpiod_set_transitory(struct gpio_desc *desc, bool transitory)
3166{
3167 struct gpio_chip *chip;
3168 unsigned long packed;
3169 int gpio;
3170 int rc;
3171
3172 VALIDATE_DESC(desc);
3173 /*
3174 * Handle FLAG_TRANSITORY first, enabling queries to gpiolib for
3175 * persistence state.
3176 */
3177 if (transitory)
3178 set_bit(FLAG_TRANSITORY, &desc->flags);
3179 else
3180 clear_bit(FLAG_TRANSITORY, &desc->flags);
3181
3182 /* If the driver supports it, set the persistence state now */
3183 chip = desc->gdev->chip;
3184 if (!chip->set_config)
3185 return 0;
3186
3187 packed = pinconf_to_config_packed(PIN_CONFIG_PERSIST_STATE,
3188 !transitory);
3189 gpio = gpio_chip_hwgpio(desc);
3190 rc = chip->set_config(chip, gpio, packed);
3191 if (rc == -ENOTSUPP) {
3192 dev_dbg(&desc->gdev->dev, "Persistence not supported for GPIO %d\n",
3193 gpio);
3194 return 0;
3195 }
3196
3197 return rc;
3198}
3199EXPORT_SYMBOL_GPL(gpiod_set_transitory);
3200
3201/**
3202 * gpiod_is_active_low - test whether a GPIO is active-low or not
3203 * @desc: the gpio descriptor to test
3204 *
3205 * Returns 1 if the GPIO is active-low, 0 otherwise.
3206 */
3207int gpiod_is_active_low(const struct gpio_desc *desc)
3208{
3209 VALIDATE_DESC(desc);
3210 return test_bit(FLAG_ACTIVE_LOW, &desc->flags);
3211}
3212EXPORT_SYMBOL_GPL(gpiod_is_active_low);
3213
3214/* I/O calls are only valid after configuration completed; the relevant
3215 * "is this a valid GPIO" error checks should already have been done.
3216 *
3217 * "Get" operations are often inlinable as reading a pin value register,
3218 * and masking the relevant bit in that register.
3219 *
3220 * When "set" operations are inlinable, they involve writing that mask to
3221 * one register to set a low value, or a different register to set it high.
3222 * Otherwise locking is needed, so there may be little value to inlining.
3223 *
3224 *------------------------------------------------------------------------
3225 *
3226 * IMPORTANT!!! The hot paths -- get/set value -- assume that callers
3227 * have requested the GPIO. That can include implicit requesting by
3228 * a direction setting call. Marking a gpio as requested locks its chip
3229 * in memory, guaranteeing that these table lookups need no more locking
3230 * and that gpiochip_remove() will fail.
3231 *
3232 * REVISIT when debugging, consider adding some instrumentation to ensure
3233 * that the GPIO was actually requested.
3234 */
3235
3236static int gpiod_get_raw_value_commit(const struct gpio_desc *desc)
3237{
3238 struct gpio_chip *chip;
3239 int offset;
3240 int value;
3241
3242 chip = desc->gdev->chip;
3243 offset = gpio_chip_hwgpio(desc);
3244 value = chip->get ? chip->get(chip, offset) : -EIO;
3245 value = value < 0 ? value : !!value;
3246 trace_gpio_value(desc_to_gpio(desc), 1, value);
3247 return value;
3248}
3249
3250static int gpio_chip_get_multiple(struct gpio_chip *chip,
3251 unsigned long *mask, unsigned long *bits)
3252{
3253 if (chip->get_multiple) {
3254 return chip->get_multiple(chip, mask, bits);
3255 } else if (chip->get) {
3256 int i, value;
3257
3258 for_each_set_bit(i, mask, chip->ngpio) {
3259 value = chip->get(chip, i);
3260 if (value < 0)
3261 return value;
3262 __assign_bit(i, bits, value);
3263 }
3264 return 0;
3265 }
3266 return -EIO;
3267}
3268
3269int gpiod_get_array_value_complex(bool raw, bool can_sleep,
3270 unsigned int array_size,
3271 struct gpio_desc **desc_array,
3272 struct gpio_array *array_info,
3273 unsigned long *value_bitmap)
3274{
3275 int ret, i = 0;
3276
3277 /*
3278 * Validate array_info against desc_array and its size.
3279 * It should immediately follow desc_array if both
3280 * have been obtained from the same gpiod_get_array() call.
3281 */
3282 if (array_info && array_info->desc == desc_array &&
3283 array_size <= array_info->size &&
3284 (void *)array_info == desc_array + array_info->size) {
3285 if (!can_sleep)
3286 WARN_ON(array_info->chip->can_sleep);
3287
3288 ret = gpio_chip_get_multiple(array_info->chip,
3289 array_info->get_mask,
3290 value_bitmap);
3291 if (ret)
3292 return ret;
3293
3294 if (!raw && !bitmap_empty(array_info->invert_mask, array_size))
3295 bitmap_xor(value_bitmap, value_bitmap,
3296 array_info->invert_mask, array_size);
3297
3298 if (bitmap_full(array_info->get_mask, array_size))
3299 return 0;
3300
3301 i = find_first_zero_bit(array_info->get_mask, array_size);
3302 } else {
3303 array_info = NULL;
3304 }
3305
3306 while (i < array_size) {
3307 struct gpio_chip *chip = desc_array[i]->gdev->chip;
3308 unsigned long fastpath[2 * BITS_TO_LONGS(FASTPATH_NGPIO)];
3309 unsigned long *mask, *bits;
3310 int first, j, ret;
3311
3312 if (likely(chip->ngpio <= FASTPATH_NGPIO)) {
3313 mask = fastpath;
3314 } else {
3315 mask = kmalloc_array(2 * BITS_TO_LONGS(chip->ngpio),
3316 sizeof(*mask),
3317 can_sleep ? GFP_KERNEL : GFP_ATOMIC);
3318 if (!mask)
3319 return -ENOMEM;
3320 }
3321
3322 bits = mask + BITS_TO_LONGS(chip->ngpio);
3323 bitmap_zero(mask, chip->ngpio);
3324
3325 if (!can_sleep)
3326 WARN_ON(chip->can_sleep);
3327
3328 /* collect all inputs belonging to the same chip */
3329 first = i;
3330 do {
3331 const struct gpio_desc *desc = desc_array[i];
3332 int hwgpio = gpio_chip_hwgpio(desc);
3333
3334 __set_bit(hwgpio, mask);
3335 i++;
3336
3337 if (array_info)
3338 i = find_next_zero_bit(array_info->get_mask,
3339 array_size, i);
3340 } while ((i < array_size) &&
3341 (desc_array[i]->gdev->chip == chip));
3342
3343 ret = gpio_chip_get_multiple(chip, mask, bits);
3344 if (ret) {
3345 if (mask != fastpath)
3346 kfree(mask);
3347 return ret;
3348 }
3349
3350 for (j = first; j < i; ) {
3351 const struct gpio_desc *desc = desc_array[j];
3352 int hwgpio = gpio_chip_hwgpio(desc);
3353 int value = test_bit(hwgpio, bits);
3354
3355 if (!raw && test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3356 value = !value;
3357 __assign_bit(j, value_bitmap, value);
3358 trace_gpio_value(desc_to_gpio(desc), 1, value);
3359 j++;
3360
3361 if (array_info)
3362 j = find_next_zero_bit(array_info->get_mask, i,
3363 j);
3364 }
3365
3366 if (mask != fastpath)
3367 kfree(mask);
3368 }
3369 return 0;
3370}
3371
3372/**
3373 * gpiod_get_raw_value() - return a gpio's raw value
3374 * @desc: gpio whose value will be returned
3375 *
3376 * Return the GPIO's raw value, i.e. the value of the physical line disregarding
3377 * its ACTIVE_LOW status, or negative errno on failure.
3378 *
3379 * This function can be called from contexts where we cannot sleep, and will
3380 * complain if the GPIO chip functions potentially sleep.
3381 */
3382int gpiod_get_raw_value(const struct gpio_desc *desc)
3383{
3384 VALIDATE_DESC(desc);
3385 /* Should be using gpiod_get_raw_value_cansleep() */
3386 WARN_ON(desc->gdev->chip->can_sleep);
3387 return gpiod_get_raw_value_commit(desc);
3388}
3389EXPORT_SYMBOL_GPL(gpiod_get_raw_value);
3390
3391/**
3392 * gpiod_get_value() - return a gpio's value
3393 * @desc: gpio whose value will be returned
3394 *
3395 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
3396 * account, or negative errno on failure.
3397 *
3398 * This function can be called from contexts where we cannot sleep, and will
3399 * complain if the GPIO chip functions potentially sleep.
3400 */
3401int gpiod_get_value(const struct gpio_desc *desc)
3402{
3403 int value;
3404
3405 VALIDATE_DESC(desc);
3406 /* Should be using gpiod_get_value_cansleep() */
3407 WARN_ON(desc->gdev->chip->can_sleep);
3408
3409 value = gpiod_get_raw_value_commit(desc);
3410 if (value < 0)
3411 return value;
3412
3413 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3414 value = !value;
3415
3416 return value;
3417}
3418EXPORT_SYMBOL_GPL(gpiod_get_value);
3419
3420/**
3421 * gpiod_get_raw_array_value() - read raw values from an array of GPIOs
3422 * @array_size: number of elements in the descriptor array / value bitmap
3423 * @desc_array: array of GPIO descriptors whose values will be read
3424 * @array_info: information on applicability of fast bitmap processing path
3425 * @value_bitmap: bitmap to store the read values
3426 *
3427 * Read the raw values of the GPIOs, i.e. the values of the physical lines
3428 * without regard for their ACTIVE_LOW status. Return 0 in case of success,
3429 * else an error code.
3430 *
3431 * This function can be called from contexts where we cannot sleep,
3432 * and it will complain if the GPIO chip functions potentially sleep.
3433 */
3434int gpiod_get_raw_array_value(unsigned int array_size,
3435 struct gpio_desc **desc_array,
3436 struct gpio_array *array_info,
3437 unsigned long *value_bitmap)
3438{
3439 if (!desc_array)
3440 return -EINVAL;
3441 return gpiod_get_array_value_complex(true, false, array_size,
3442 desc_array, array_info,
3443 value_bitmap);
3444}
3445EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value);
3446
3447/**
3448 * gpiod_get_array_value() - read values from an array of GPIOs
3449 * @array_size: number of elements in the descriptor array / value bitmap
3450 * @desc_array: array of GPIO descriptors whose values will be read
3451 * @array_info: information on applicability of fast bitmap processing path
3452 * @value_bitmap: bitmap to store the read values
3453 *
3454 * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3455 * into account. Return 0 in case of success, else an error code.
3456 *
3457 * This function can be called from contexts where we cannot sleep,
3458 * and it will complain if the GPIO chip functions potentially sleep.
3459 */
3460int gpiod_get_array_value(unsigned int array_size,
3461 struct gpio_desc **desc_array,
3462 struct gpio_array *array_info,
3463 unsigned long *value_bitmap)
3464{
3465 if (!desc_array)
3466 return -EINVAL;
3467 return gpiod_get_array_value_complex(false, false, array_size,
3468 desc_array, array_info,
3469 value_bitmap);
3470}
3471EXPORT_SYMBOL_GPL(gpiod_get_array_value);
3472
3473/*
3474 * gpio_set_open_drain_value_commit() - Set the open drain gpio's value.
3475 * @desc: gpio descriptor whose state need to be set.
3476 * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
3477 */
3478static void gpio_set_open_drain_value_commit(struct gpio_desc *desc, bool value)
3479{
3480 int ret = 0;
3481 struct gpio_chip *chip = desc->gdev->chip;
3482 int offset = gpio_chip_hwgpio(desc);
3483
3484 if (value) {
3485 ret = chip->direction_input(chip, offset);
3486 } else {
3487 ret = chip->direction_output(chip, offset, 0);
3488 if (!ret)
3489 set_bit(FLAG_IS_OUT, &desc->flags);
3490 }
3491 trace_gpio_direction(desc_to_gpio(desc), value, ret);
3492 if (ret < 0)
3493 gpiod_err(desc,
3494 "%s: Error in set_value for open drain err %d\n",
3495 __func__, ret);
3496}
3497
3498/*
3499 * _gpio_set_open_source_value() - Set the open source gpio's value.
3500 * @desc: gpio descriptor whose state need to be set.
3501 * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
3502 */
3503static void gpio_set_open_source_value_commit(struct gpio_desc *desc, bool value)
3504{
3505 int ret = 0;
3506 struct gpio_chip *chip = desc->gdev->chip;
3507 int offset = gpio_chip_hwgpio(desc);
3508
3509 if (value) {
3510 ret = chip->direction_output(chip, offset, 1);
3511 if (!ret)
3512 set_bit(FLAG_IS_OUT, &desc->flags);
3513 } else {
3514 ret = chip->direction_input(chip, offset);
3515 }
3516 trace_gpio_direction(desc_to_gpio(desc), !value, ret);
3517 if (ret < 0)
3518 gpiod_err(desc,
3519 "%s: Error in set_value for open source err %d\n",
3520 __func__, ret);
3521}
3522
3523static void gpiod_set_raw_value_commit(struct gpio_desc *desc, bool value)
3524{
3525 struct gpio_chip *chip;
3526
3527 chip = desc->gdev->chip;
3528 trace_gpio_value(desc_to_gpio(desc), 0, value);
3529 chip->set(chip, gpio_chip_hwgpio(desc), value);
3530}
3531
3532/*
3533 * set multiple outputs on the same chip;
3534 * use the chip's set_multiple function if available;
3535 * otherwise set the outputs sequentially;
3536 * @mask: bit mask array; one bit per output; BITS_PER_LONG bits per word
3537 * defines which outputs are to be changed
3538 * @bits: bit value array; one bit per output; BITS_PER_LONG bits per word
3539 * defines the values the outputs specified by mask are to be set to
3540 */
3541static void gpio_chip_set_multiple(struct gpio_chip *chip,
3542 unsigned long *mask, unsigned long *bits)
3543{
3544 if (chip->set_multiple) {
3545 chip->set_multiple(chip, mask, bits);
3546 } else {
3547 unsigned int i;
3548
3549 /* set outputs if the corresponding mask bit is set */
3550 for_each_set_bit(i, mask, chip->ngpio)
3551 chip->set(chip, i, test_bit(i, bits));
3552 }
3553}
3554
3555int gpiod_set_array_value_complex(bool raw, bool can_sleep,
3556 unsigned int array_size,
3557 struct gpio_desc **desc_array,
3558 struct gpio_array *array_info,
3559 unsigned long *value_bitmap)
3560{
3561 int i = 0;
3562
3563 /*
3564 * Validate array_info against desc_array and its size.
3565 * It should immediately follow desc_array if both
3566 * have been obtained from the same gpiod_get_array() call.
3567 */
3568 if (array_info && array_info->desc == desc_array &&
3569 array_size <= array_info->size &&
3570 (void *)array_info == desc_array + array_info->size) {
3571 if (!can_sleep)
3572 WARN_ON(array_info->chip->can_sleep);
3573
3574 if (!raw && !bitmap_empty(array_info->invert_mask, array_size))
3575 bitmap_xor(value_bitmap, value_bitmap,
3576 array_info->invert_mask, array_size);
3577
3578 gpio_chip_set_multiple(array_info->chip, array_info->set_mask,
3579 value_bitmap);
3580
3581 if (bitmap_full(array_info->set_mask, array_size))
3582 return 0;
3583
3584 i = find_first_zero_bit(array_info->set_mask, array_size);
3585 } else {
3586 array_info = NULL;
3587 }
3588
3589 while (i < array_size) {
3590 struct gpio_chip *chip = desc_array[i]->gdev->chip;
3591 unsigned long fastpath[2 * BITS_TO_LONGS(FASTPATH_NGPIO)];
3592 unsigned long *mask, *bits;
3593 int count = 0;
3594
3595 if (likely(chip->ngpio <= FASTPATH_NGPIO)) {
3596 mask = fastpath;
3597 } else {
3598 mask = kmalloc_array(2 * BITS_TO_LONGS(chip->ngpio),
3599 sizeof(*mask),
3600 can_sleep ? GFP_KERNEL : GFP_ATOMIC);
3601 if (!mask)
3602 return -ENOMEM;
3603 }
3604
3605 bits = mask + BITS_TO_LONGS(chip->ngpio);
3606 bitmap_zero(mask, chip->ngpio);
3607
3608 if (!can_sleep)
3609 WARN_ON(chip->can_sleep);
3610
3611 do {
3612 struct gpio_desc *desc = desc_array[i];
3613 int hwgpio = gpio_chip_hwgpio(desc);
3614 int value = test_bit(i, value_bitmap);
3615
3616 /*
3617 * Pins applicable for fast input but not for
3618 * fast output processing may have been already
3619 * inverted inside the fast path, skip them.
3620 */
3621 if (!raw && !(array_info &&
3622 test_bit(i, array_info->invert_mask)) &&
3623 test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3624 value = !value;
3625 trace_gpio_value(desc_to_gpio(desc), 0, value);
3626 /*
3627 * collect all normal outputs belonging to the same chip
3628 * open drain and open source outputs are set individually
3629 */
3630 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags) && !raw) {
3631 gpio_set_open_drain_value_commit(desc, value);
3632 } else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags) && !raw) {
3633 gpio_set_open_source_value_commit(desc, value);
3634 } else {
3635 __set_bit(hwgpio, mask);
3636 if (value)
3637 __set_bit(hwgpio, bits);
3638 else
3639 __clear_bit(hwgpio, bits);
3640 count++;
3641 }
3642 i++;
3643
3644 if (array_info)
3645 i = find_next_zero_bit(array_info->set_mask,
3646 array_size, i);
3647 } while ((i < array_size) &&
3648 (desc_array[i]->gdev->chip == chip));
3649 /* push collected bits to outputs */
3650 if (count != 0)
3651 gpio_chip_set_multiple(chip, mask, bits);
3652
3653 if (mask != fastpath)
3654 kfree(mask);
3655 }
3656 return 0;
3657}
3658
3659/**
3660 * gpiod_set_raw_value() - assign a gpio's raw value
3661 * @desc: gpio whose value will be assigned
3662 * @value: value to assign
3663 *
3664 * Set the raw value of the GPIO, i.e. the value of its physical line without
3665 * regard for its ACTIVE_LOW status.
3666 *
3667 * This function can be called from contexts where we cannot sleep, and will
3668 * complain if the GPIO chip functions potentially sleep.
3669 */
3670void gpiod_set_raw_value(struct gpio_desc *desc, int value)
3671{
3672 VALIDATE_DESC_VOID(desc);
3673 /* Should be using gpiod_set_raw_value_cansleep() */
3674 WARN_ON(desc->gdev->chip->can_sleep);
3675 gpiod_set_raw_value_commit(desc, value);
3676}
3677EXPORT_SYMBOL_GPL(gpiod_set_raw_value);
3678
3679/**
3680 * gpiod_set_value_nocheck() - set a GPIO line value without checking
3681 * @desc: the descriptor to set the value on
3682 * @value: value to set
3683 *
3684 * This sets the value of a GPIO line backing a descriptor, applying
3685 * different semantic quirks like active low and open drain/source
3686 * handling.
3687 */
3688static void gpiod_set_value_nocheck(struct gpio_desc *desc, int value)
3689{
3690 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3691 value = !value;
3692 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags))
3693 gpio_set_open_drain_value_commit(desc, value);
3694 else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags))
3695 gpio_set_open_source_value_commit(desc, value);
3696 else
3697 gpiod_set_raw_value_commit(desc, value);
3698}
3699
3700/**
3701 * gpiod_set_value() - assign a gpio's value
3702 * @desc: gpio whose value will be assigned
3703 * @value: value to assign
3704 *
3705 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW,
3706 * OPEN_DRAIN and OPEN_SOURCE flags into account.
3707 *
3708 * This function can be called from contexts where we cannot sleep, and will
3709 * complain if the GPIO chip functions potentially sleep.
3710 */
3711void gpiod_set_value(struct gpio_desc *desc, int value)
3712{
3713 VALIDATE_DESC_VOID(desc);
3714 /* Should be using gpiod_set_value_cansleep() */
3715 WARN_ON(desc->gdev->chip->can_sleep);
3716 gpiod_set_value_nocheck(desc, value);
3717}
3718EXPORT_SYMBOL_GPL(gpiod_set_value);
3719
3720/**
3721 * gpiod_set_raw_array_value() - assign values to an array of GPIOs
3722 * @array_size: number of elements in the descriptor array / value bitmap
3723 * @desc_array: array of GPIO descriptors whose values will be assigned
3724 * @array_info: information on applicability of fast bitmap processing path
3725 * @value_bitmap: bitmap of values to assign
3726 *
3727 * Set the raw values of the GPIOs, i.e. the values of the physical lines
3728 * without regard for their ACTIVE_LOW status.
3729 *
3730 * This function can be called from contexts where we cannot sleep, and will
3731 * complain if the GPIO chip functions potentially sleep.
3732 */
3733int gpiod_set_raw_array_value(unsigned int array_size,
3734 struct gpio_desc **desc_array,
3735 struct gpio_array *array_info,
3736 unsigned long *value_bitmap)
3737{
3738 if (!desc_array)
3739 return -EINVAL;
3740 return gpiod_set_array_value_complex(true, false, array_size,
3741 desc_array, array_info, value_bitmap);
3742}
3743EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value);
3744
3745/**
3746 * gpiod_set_array_value() - assign values to an array of GPIOs
3747 * @array_size: number of elements in the descriptor array / value bitmap
3748 * @desc_array: array of GPIO descriptors whose values will be assigned
3749 * @array_info: information on applicability of fast bitmap processing path
3750 * @value_bitmap: bitmap of values to assign
3751 *
3752 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3753 * into account.
3754 *
3755 * This function can be called from contexts where we cannot sleep, and will
3756 * complain if the GPIO chip functions potentially sleep.
3757 */
3758int gpiod_set_array_value(unsigned int array_size,
3759 struct gpio_desc **desc_array,
3760 struct gpio_array *array_info,
3761 unsigned long *value_bitmap)
3762{
3763 if (!desc_array)
3764 return -EINVAL;
3765 return gpiod_set_array_value_complex(false, false, array_size,
3766 desc_array, array_info,
3767 value_bitmap);
3768}
3769EXPORT_SYMBOL_GPL(gpiod_set_array_value);
3770
3771/**
3772 * gpiod_cansleep() - report whether gpio value access may sleep
3773 * @desc: gpio to check
3774 *
3775 */
3776int gpiod_cansleep(const struct gpio_desc *desc)
3777{
3778 VALIDATE_DESC(desc);
3779 return desc->gdev->chip->can_sleep;
3780}
3781EXPORT_SYMBOL_GPL(gpiod_cansleep);
3782
3783/**
3784 * gpiod_set_consumer_name() - set the consumer name for the descriptor
3785 * @desc: gpio to set the consumer name on
3786 * @name: the new consumer name
3787 */
3788int gpiod_set_consumer_name(struct gpio_desc *desc, const char *name)
3789{
3790 VALIDATE_DESC(desc);
3791 if (name) {
3792 name = kstrdup_const(name, GFP_KERNEL);
3793 if (!name)
3794 return -ENOMEM;
3795 }
3796
3797 kfree_const(desc->label);
3798 desc_set_label(desc, name);
3799
3800 return 0;
3801}
3802EXPORT_SYMBOL_GPL(gpiod_set_consumer_name);
3803
3804/**
3805 * gpiod_to_irq() - return the IRQ corresponding to a GPIO
3806 * @desc: gpio whose IRQ will be returned (already requested)
3807 *
3808 * Return the IRQ corresponding to the passed GPIO, or an error code in case of
3809 * error.
3810 */
3811int gpiod_to_irq(const struct gpio_desc *desc)
3812{
3813 struct gpio_chip *chip;
3814 int offset;
3815
3816 /*
3817 * Cannot VALIDATE_DESC() here as gpiod_to_irq() consumer semantics
3818 * requires this function to not return zero on an invalid descriptor
3819 * but rather a negative error number.
3820 */
3821 if (!desc || IS_ERR(desc) || !desc->gdev || !desc->gdev->chip)
3822 return -EINVAL;
3823
3824 chip = desc->gdev->chip;
3825 offset = gpio_chip_hwgpio(desc);
3826 if (chip->to_irq) {
3827 int retirq = chip->to_irq(chip, offset);
3828
3829 /* Zero means NO_IRQ */
3830 if (!retirq)
3831 return -ENXIO;
3832
3833 return retirq;
3834 }
3835 return -ENXIO;
3836}
3837EXPORT_SYMBOL_GPL(gpiod_to_irq);
3838
3839/**
3840 * gpiochip_lock_as_irq() - lock a GPIO to be used as IRQ
3841 * @chip: the chip the GPIO to lock belongs to
3842 * @offset: the offset of the GPIO to lock as IRQ
3843 *
3844 * This is used directly by GPIO drivers that want to lock down
3845 * a certain GPIO line to be used for IRQs.
3846 */
3847int gpiochip_lock_as_irq(struct gpio_chip *chip, unsigned int offset)
3848{
3849 struct gpio_desc *desc;
3850
3851 desc = gpiochip_get_desc(chip, offset);
3852 if (IS_ERR(desc))
3853 return PTR_ERR(desc);
3854
3855 /*
3856 * If it's fast: flush the direction setting if something changed
3857 * behind our back
3858 */
3859 if (!chip->can_sleep && chip->get_direction) {
3860 int dir = gpiod_get_direction(desc);
3861
3862 if (dir < 0) {
3863 chip_err(chip, "%s: cannot get GPIO direction\n",
3864 __func__);
3865 return dir;
3866 }
3867 }
3868
3869 if (test_bit(FLAG_IS_OUT, &desc->flags)) {
3870 chip_err(chip,
3871 "%s: tried to flag a GPIO set as output for IRQ\n",
3872 __func__);
3873 return -EIO;
3874 }
3875
3876 set_bit(FLAG_USED_AS_IRQ, &desc->flags);
3877 set_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
3878
3879 /*
3880 * If the consumer has not set up a label (such as when the
3881 * IRQ is referenced from .to_irq()) we set up a label here
3882 * so it is clear this is used as an interrupt.
3883 */
3884 if (!desc->label)
3885 desc_set_label(desc, "interrupt");
3886
3887 return 0;
3888}
3889EXPORT_SYMBOL_GPL(gpiochip_lock_as_irq);
3890
3891/**
3892 * gpiochip_unlock_as_irq() - unlock a GPIO used as IRQ
3893 * @chip: the chip the GPIO to lock belongs to
3894 * @offset: the offset of the GPIO to lock as IRQ
3895 *
3896 * This is used directly by GPIO drivers that want to indicate
3897 * that a certain GPIO is no longer used exclusively for IRQ.
3898 */
3899void gpiochip_unlock_as_irq(struct gpio_chip *chip, unsigned int offset)
3900{
3901 struct gpio_desc *desc;
3902
3903 desc = gpiochip_get_desc(chip, offset);
3904 if (IS_ERR(desc))
3905 return;
3906
3907 clear_bit(FLAG_USED_AS_IRQ, &desc->flags);
3908 clear_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
3909
3910 /* If we only had this marking, erase it */
3911 if (desc->label && !strcmp(desc->label, "interrupt"))
3912 desc_set_label(desc, NULL);
3913}
3914EXPORT_SYMBOL_GPL(gpiochip_unlock_as_irq);
3915
3916void gpiochip_disable_irq(struct gpio_chip *chip, unsigned int offset)
3917{
3918 struct gpio_desc *desc = gpiochip_get_desc(chip, offset);
3919
3920 if (!IS_ERR(desc) &&
3921 !WARN_ON(!test_bit(FLAG_USED_AS_IRQ, &desc->flags)))
3922 clear_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
3923}
3924EXPORT_SYMBOL_GPL(gpiochip_disable_irq);
3925
3926void gpiochip_enable_irq(struct gpio_chip *chip, unsigned int offset)
3927{
3928 struct gpio_desc *desc = gpiochip_get_desc(chip, offset);
3929
3930 if (!IS_ERR(desc) &&
3931 !WARN_ON(!test_bit(FLAG_USED_AS_IRQ, &desc->flags))) {
3932 WARN_ON(test_bit(FLAG_IS_OUT, &desc->flags));
3933 set_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
3934 }
3935}
3936EXPORT_SYMBOL_GPL(gpiochip_enable_irq);
3937
3938bool gpiochip_line_is_irq(struct gpio_chip *chip, unsigned int offset)
3939{
3940 if (offset >= chip->ngpio)
3941 return false;
3942
3943 return test_bit(FLAG_USED_AS_IRQ, &chip->gpiodev->descs[offset].flags);
3944}
3945EXPORT_SYMBOL_GPL(gpiochip_line_is_irq);
3946
3947int gpiochip_reqres_irq(struct gpio_chip *chip, unsigned int offset)
3948{
3949 int ret;
3950
3951 if (!try_module_get(chip->gpiodev->owner))
3952 return -ENODEV;
3953
3954 ret = gpiochip_lock_as_irq(chip, offset);
3955 if (ret) {
3956 chip_err(chip, "unable to lock HW IRQ %u for IRQ\n", offset);
3957 module_put(chip->gpiodev->owner);
3958 return ret;
3959 }
3960 return 0;
3961}
3962EXPORT_SYMBOL_GPL(gpiochip_reqres_irq);
3963
3964void gpiochip_relres_irq(struct gpio_chip *chip, unsigned int offset)
3965{
3966 gpiochip_unlock_as_irq(chip, offset);
3967 module_put(chip->gpiodev->owner);
3968}
3969EXPORT_SYMBOL_GPL(gpiochip_relres_irq);
3970
3971bool gpiochip_line_is_open_drain(struct gpio_chip *chip, unsigned int offset)
3972{
3973 if (offset >= chip->ngpio)
3974 return false;
3975
3976 return test_bit(FLAG_OPEN_DRAIN, &chip->gpiodev->descs[offset].flags);
3977}
3978EXPORT_SYMBOL_GPL(gpiochip_line_is_open_drain);
3979
3980bool gpiochip_line_is_open_source(struct gpio_chip *chip, unsigned int offset)
3981{
3982 if (offset >= chip->ngpio)
3983 return false;
3984
3985 return test_bit(FLAG_OPEN_SOURCE, &chip->gpiodev->descs[offset].flags);
3986}
3987EXPORT_SYMBOL_GPL(gpiochip_line_is_open_source);
3988
3989bool gpiochip_line_is_persistent(struct gpio_chip *chip, unsigned int offset)
3990{
3991 if (offset >= chip->ngpio)
3992 return false;
3993
3994 return !test_bit(FLAG_TRANSITORY, &chip->gpiodev->descs[offset].flags);
3995}
3996EXPORT_SYMBOL_GPL(gpiochip_line_is_persistent);
3997
3998/**
3999 * gpiod_get_raw_value_cansleep() - return a gpio's raw value
4000 * @desc: gpio whose value will be returned
4001 *
4002 * Return the GPIO's raw value, i.e. the value of the physical line disregarding
4003 * its ACTIVE_LOW status, or negative errno on failure.
4004 *
4005 * This function is to be called from contexts that can sleep.
4006 */
4007int gpiod_get_raw_value_cansleep(const struct gpio_desc *desc)
4008{
4009 might_sleep_if(extra_checks);
4010 VALIDATE_DESC(desc);
4011 return gpiod_get_raw_value_commit(desc);
4012}
4013EXPORT_SYMBOL_GPL(gpiod_get_raw_value_cansleep);
4014
4015/**
4016 * gpiod_get_value_cansleep() - return a gpio's value
4017 * @desc: gpio whose value will be returned
4018 *
4019 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
4020 * account, or negative errno on failure.
4021 *
4022 * This function is to be called from contexts that can sleep.
4023 */
4024int gpiod_get_value_cansleep(const struct gpio_desc *desc)
4025{
4026 int value;
4027
4028 might_sleep_if(extra_checks);
4029 VALIDATE_DESC(desc);
4030 value = gpiod_get_raw_value_commit(desc);
4031 if (value < 0)
4032 return value;
4033
4034 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
4035 value = !value;
4036
4037 return value;
4038}
4039EXPORT_SYMBOL_GPL(gpiod_get_value_cansleep);
4040
4041/**
4042 * gpiod_get_raw_array_value_cansleep() - read raw values from an array of GPIOs
4043 * @array_size: number of elements in the descriptor array / value bitmap
4044 * @desc_array: array of GPIO descriptors whose values will be read
4045 * @array_info: information on applicability of fast bitmap processing path
4046 * @value_bitmap: bitmap to store the read values
4047 *
4048 * Read the raw values of the GPIOs, i.e. the values of the physical lines
4049 * without regard for their ACTIVE_LOW status. Return 0 in case of success,
4050 * else an error code.
4051 *
4052 * This function is to be called from contexts that can sleep.
4053 */
4054int gpiod_get_raw_array_value_cansleep(unsigned int array_size,
4055 struct gpio_desc **desc_array,
4056 struct gpio_array *array_info,
4057 unsigned long *value_bitmap)
4058{
4059 might_sleep_if(extra_checks);
4060 if (!desc_array)
4061 return -EINVAL;
4062 return gpiod_get_array_value_complex(true, true, array_size,
4063 desc_array, array_info,
4064 value_bitmap);
4065}
4066EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value_cansleep);
4067
4068/**
4069 * gpiod_get_array_value_cansleep() - read values from an array of GPIOs
4070 * @array_size: number of elements in the descriptor array / value bitmap
4071 * @desc_array: array of GPIO descriptors whose values will be read
4072 * @array_info: information on applicability of fast bitmap processing path
4073 * @value_bitmap: bitmap to store the read values
4074 *
4075 * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
4076 * into account. Return 0 in case of success, else an error code.
4077 *
4078 * This function is to be called from contexts that can sleep.
4079 */
4080int gpiod_get_array_value_cansleep(unsigned int array_size,
4081 struct gpio_desc **desc_array,
4082 struct gpio_array *array_info,
4083 unsigned long *value_bitmap)
4084{
4085 might_sleep_if(extra_checks);
4086 if (!desc_array)
4087 return -EINVAL;
4088 return gpiod_get_array_value_complex(false, true, array_size,
4089 desc_array, array_info,
4090 value_bitmap);
4091}
4092EXPORT_SYMBOL_GPL(gpiod_get_array_value_cansleep);
4093
4094/**
4095 * gpiod_set_raw_value_cansleep() - assign a gpio's raw value
4096 * @desc: gpio whose value will be assigned
4097 * @value: value to assign
4098 *
4099 * Set the raw value of the GPIO, i.e. the value of its physical line without
4100 * regard for its ACTIVE_LOW status.
4101 *
4102 * This function is to be called from contexts that can sleep.
4103 */
4104void gpiod_set_raw_value_cansleep(struct gpio_desc *desc, int value)
4105{
4106 might_sleep_if(extra_checks);
4107 VALIDATE_DESC_VOID(desc);
4108 gpiod_set_raw_value_commit(desc, value);
4109}
4110EXPORT_SYMBOL_GPL(gpiod_set_raw_value_cansleep);
4111
4112/**
4113 * gpiod_set_value_cansleep() - assign a gpio's value
4114 * @desc: gpio whose value will be assigned
4115 * @value: value to assign
4116 *
4117 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
4118 * account
4119 *
4120 * This function is to be called from contexts that can sleep.
4121 */
4122void gpiod_set_value_cansleep(struct gpio_desc *desc, int value)
4123{
4124 might_sleep_if(extra_checks);
4125 VALIDATE_DESC_VOID(desc);
4126 gpiod_set_value_nocheck(desc, value);
4127}
4128EXPORT_SYMBOL_GPL(gpiod_set_value_cansleep);
4129
4130/**
4131 * gpiod_set_raw_array_value_cansleep() - assign values to an array of GPIOs
4132 * @array_size: number of elements in the descriptor array / value bitmap
4133 * @desc_array: array of GPIO descriptors whose values will be assigned
4134 * @array_info: information on applicability of fast bitmap processing path
4135 * @value_bitmap: bitmap of values to assign
4136 *
4137 * Set the raw values of the GPIOs, i.e. the values of the physical lines
4138 * without regard for their ACTIVE_LOW status.
4139 *
4140 * This function is to be called from contexts that can sleep.
4141 */
4142int gpiod_set_raw_array_value_cansleep(unsigned int array_size,
4143 struct gpio_desc **desc_array,
4144 struct gpio_array *array_info,
4145 unsigned long *value_bitmap)
4146{
4147 might_sleep_if(extra_checks);
4148 if (!desc_array)
4149 return -EINVAL;
4150 return gpiod_set_array_value_complex(true, true, array_size, desc_array,
4151 array_info, value_bitmap);
4152}
4153EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value_cansleep);
4154
4155/**
4156 * gpiod_add_lookup_tables() - register GPIO device consumers
4157 * @tables: list of tables of consumers to register
4158 * @n: number of tables in the list
4159 */
4160void gpiod_add_lookup_tables(struct gpiod_lookup_table **tables, size_t n)
4161{
4162 unsigned int i;
4163
4164 mutex_lock(&gpio_lookup_lock);
4165
4166 for (i = 0; i < n; i++)
4167 list_add_tail(&tables[i]->list, &gpio_lookup_list);
4168
4169 mutex_unlock(&gpio_lookup_lock);
4170}
4171
4172/**
4173 * gpiod_set_array_value_cansleep() - assign values to an array of GPIOs
4174 * @array_size: number of elements in the descriptor array / value bitmap
4175 * @desc_array: array of GPIO descriptors whose values will be assigned
4176 * @array_info: information on applicability of fast bitmap processing path
4177 * @value_bitmap: bitmap of values to assign
4178 *
4179 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
4180 * into account.
4181 *
4182 * This function is to be called from contexts that can sleep.
4183 */
4184int gpiod_set_array_value_cansleep(unsigned int array_size,
4185 struct gpio_desc **desc_array,
4186 struct gpio_array *array_info,
4187 unsigned long *value_bitmap)
4188{
4189 might_sleep_if(extra_checks);
4190 if (!desc_array)
4191 return -EINVAL;
4192 return gpiod_set_array_value_complex(false, true, array_size,
4193 desc_array, array_info,
4194 value_bitmap);
4195}
4196EXPORT_SYMBOL_GPL(gpiod_set_array_value_cansleep);
4197
4198/**
4199 * gpiod_add_lookup_table() - register GPIO device consumers
4200 * @table: table of consumers to register
4201 */
4202void gpiod_add_lookup_table(struct gpiod_lookup_table *table)
4203{
4204 mutex_lock(&gpio_lookup_lock);
4205
4206 list_add_tail(&table->list, &gpio_lookup_list);
4207
4208 mutex_unlock(&gpio_lookup_lock);
4209}
4210EXPORT_SYMBOL_GPL(gpiod_add_lookup_table);
4211
4212/**
4213 * gpiod_remove_lookup_table() - unregister GPIO device consumers
4214 * @table: table of consumers to unregister
4215 */
4216void gpiod_remove_lookup_table(struct gpiod_lookup_table *table)
4217{
4218 mutex_lock(&gpio_lookup_lock);
4219
4220 list_del(&table->list);
4221
4222 mutex_unlock(&gpio_lookup_lock);
4223}
4224EXPORT_SYMBOL_GPL(gpiod_remove_lookup_table);
4225
4226/**
4227 * gpiod_add_hogs() - register a set of GPIO hogs from machine code
4228 * @hogs: table of gpio hog entries with a zeroed sentinel at the end
4229 */
4230void gpiod_add_hogs(struct gpiod_hog *hogs)
4231{
4232 struct gpio_chip *chip;
4233 struct gpiod_hog *hog;
4234
4235 mutex_lock(&gpio_machine_hogs_mutex);
4236
4237 for (hog = &hogs[0]; hog->chip_label; hog++) {
4238 list_add_tail(&hog->list, &gpio_machine_hogs);
4239
4240 /*
4241 * The chip may have been registered earlier, so check if it
4242 * exists and, if so, try to hog the line now.
4243 */
4244 chip = find_chip_by_name(hog->chip_label);
4245 if (chip)
4246 gpiochip_machine_hog(chip, hog);
4247 }
4248
4249 mutex_unlock(&gpio_machine_hogs_mutex);
4250}
4251EXPORT_SYMBOL_GPL(gpiod_add_hogs);
4252
4253static struct gpiod_lookup_table *gpiod_find_lookup_table(struct device *dev)
4254{
4255 const char *dev_id = dev ? dev_name(dev) : NULL;
4256 struct gpiod_lookup_table *table;
4257
4258 mutex_lock(&gpio_lookup_lock);
4259
4260 list_for_each_entry(table, &gpio_lookup_list, list) {
4261 if (table->dev_id && dev_id) {
4262 /*
4263 * Valid strings on both ends, must be identical to have
4264 * a match
4265 */
4266 if (!strcmp(table->dev_id, dev_id))
4267 goto found;
4268 } else {
4269 /*
4270 * One of the pointers is NULL, so both must be to have
4271 * a match
4272 */
4273 if (dev_id == table->dev_id)
4274 goto found;
4275 }
4276 }
4277 table = NULL;
4278
4279found:
4280 mutex_unlock(&gpio_lookup_lock);
4281 return table;
4282}
4283
4284static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id,
4285 unsigned int idx, unsigned long *flags)
4286{
4287 struct gpio_desc *desc = ERR_PTR(-ENOENT);
4288 struct gpiod_lookup_table *table;
4289 struct gpiod_lookup *p;
4290
4291 table = gpiod_find_lookup_table(dev);
4292 if (!table)
4293 return desc;
4294
4295 for (p = &table->table[0]; p->chip_label; p++) {
4296 struct gpio_chip *chip;
4297
4298 /* idx must always match exactly */
4299 if (p->idx != idx)
4300 continue;
4301
4302 /* If the lookup entry has a con_id, require exact match */
4303 if (p->con_id && (!con_id || strcmp(p->con_id, con_id)))
4304 continue;
4305
4306 chip = find_chip_by_name(p->chip_label);
4307
4308 if (!chip) {
4309 /*
4310 * As the lookup table indicates a chip with
4311 * p->chip_label should exist, assume it may
4312 * still appear later and let the interested
4313 * consumer be probed again or let the Deferred
4314 * Probe infrastructure handle the error.
4315 */
4316 dev_warn(dev, "cannot find GPIO chip %s, deferring\n",
4317 p->chip_label);
4318 return ERR_PTR(-EPROBE_DEFER);
4319 }
4320
4321 if (chip->ngpio <= p->chip_hwnum) {
4322 dev_err(dev,
4323 "requested GPIO %d is out of range [0..%d] for chip %s\n",
4324 idx, chip->ngpio, chip->label);
4325 return ERR_PTR(-EINVAL);
4326 }
4327
4328 desc = gpiochip_get_desc(chip, p->chip_hwnum);
4329 *flags = p->flags;
4330
4331 return desc;
4332 }
4333
4334 return desc;
4335}
4336
4337static int platform_gpio_count(struct device *dev, const char *con_id)
4338{
4339 struct gpiod_lookup_table *table;
4340 struct gpiod_lookup *p;
4341 unsigned int count = 0;
4342
4343 table = gpiod_find_lookup_table(dev);
4344 if (!table)
4345 return -ENOENT;
4346
4347 for (p = &table->table[0]; p->chip_label; p++) {
4348 if ((con_id && p->con_id && !strcmp(con_id, p->con_id)) ||
4349 (!con_id && !p->con_id))
4350 count++;
4351 }
4352 if (!count)
4353 return -ENOENT;
4354
4355 return count;
4356}
4357
4358/**
4359 * gpiod_count - return the number of GPIOs associated with a device / function
4360 * or -ENOENT if no GPIO has been assigned to the requested function
4361 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4362 * @con_id: function within the GPIO consumer
4363 */
4364int gpiod_count(struct device *dev, const char *con_id)
4365{
4366 int count = -ENOENT;
4367
4368 if (IS_ENABLED(CONFIG_OF) && dev && dev->of_node)
4369 count = of_gpio_get_count(dev, con_id);
4370 else if (IS_ENABLED(CONFIG_ACPI) && dev && ACPI_HANDLE(dev))
4371 count = acpi_gpio_count(dev, con_id);
4372
4373 if (count < 0)
4374 count = platform_gpio_count(dev, con_id);
4375
4376 return count;
4377}
4378EXPORT_SYMBOL_GPL(gpiod_count);
4379
4380/**
4381 * gpiod_get - obtain a GPIO for a given GPIO function
4382 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4383 * @con_id: function within the GPIO consumer
4384 * @flags: optional GPIO initialization flags
4385 *
4386 * Return the GPIO descriptor corresponding to the function con_id of device
4387 * dev, -ENOENT if no GPIO has been assigned to the requested function, or
4388 * another IS_ERR() code if an error occurred while trying to acquire the GPIO.
4389 */
4390struct gpio_desc *__must_check gpiod_get(struct device *dev, const char *con_id,
4391 enum gpiod_flags flags)
4392{
4393 return gpiod_get_index(dev, con_id, 0, flags);
4394}
4395EXPORT_SYMBOL_GPL(gpiod_get);
4396
4397/**
4398 * gpiod_get_optional - obtain an optional GPIO for a given GPIO function
4399 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4400 * @con_id: function within the GPIO consumer
4401 * @flags: optional GPIO initialization flags
4402 *
4403 * This is equivalent to gpiod_get(), except that when no GPIO was assigned to
4404 * the requested function it will return NULL. This is convenient for drivers
4405 * that need to handle optional GPIOs.
4406 */
4407struct gpio_desc *__must_check gpiod_get_optional(struct device *dev,
4408 const char *con_id,
4409 enum gpiod_flags flags)
4410{
4411 return gpiod_get_index_optional(dev, con_id, 0, flags);
4412}
4413EXPORT_SYMBOL_GPL(gpiod_get_optional);
4414
4415
4416/**
4417 * gpiod_configure_flags - helper function to configure a given GPIO
4418 * @desc: gpio whose value will be assigned
4419 * @con_id: function within the GPIO consumer
4420 * @lflags: bitmask of gpio_lookup_flags GPIO_* values - returned from
4421 * of_find_gpio() or of_get_gpio_hog()
4422 * @dflags: gpiod_flags - optional GPIO initialization flags
4423 *
4424 * Return 0 on success, -ENOENT if no GPIO has been assigned to the
4425 * requested function and/or index, or another IS_ERR() code if an error
4426 * occurred while trying to acquire the GPIO.
4427 */
4428int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id,
4429 unsigned long lflags, enum gpiod_flags dflags)
4430{
4431 int ret;
4432
4433 if (lflags & GPIO_ACTIVE_LOW)
4434 set_bit(FLAG_ACTIVE_LOW, &desc->flags);
4435
4436 if (lflags & GPIO_OPEN_DRAIN)
4437 set_bit(FLAG_OPEN_DRAIN, &desc->flags);
4438 else if (dflags & GPIOD_FLAGS_BIT_OPEN_DRAIN) {
4439 /*
4440 * This enforces open drain mode from the consumer side.
4441 * This is necessary for some busses like I2C, but the lookup
4442 * should *REALLY* have specified them as open drain in the
4443 * first place, so print a little warning here.
4444 */
4445 set_bit(FLAG_OPEN_DRAIN, &desc->flags);
4446 gpiod_warn(desc,
4447 "enforced open drain please flag it properly in DT/ACPI DSDT/board file\n");
4448 }
4449
4450 if (lflags & GPIO_OPEN_SOURCE)
4451 set_bit(FLAG_OPEN_SOURCE, &desc->flags);
4452
4453 if ((lflags & GPIO_PULL_UP) && (lflags & GPIO_PULL_DOWN)) {
4454 gpiod_err(desc,
4455 "both pull-up and pull-down enabled, invalid configuration\n");
4456 return -EINVAL;
4457 }
4458
4459 if (lflags & GPIO_PULL_UP)
4460 set_bit(FLAG_PULL_UP, &desc->flags);
4461 else if (lflags & GPIO_PULL_DOWN)
4462 set_bit(FLAG_PULL_DOWN, &desc->flags);
4463
4464 ret = gpiod_set_transitory(desc, (lflags & GPIO_TRANSITORY));
4465 if (ret < 0)
4466 return ret;
4467
4468 /* No particular flag request, return here... */
4469 if (!(dflags & GPIOD_FLAGS_BIT_DIR_SET)) {
4470 pr_debug("no flags found for %s\n", con_id);
4471 return 0;
4472 }
4473
4474 /* Process flags */
4475 if (dflags & GPIOD_FLAGS_BIT_DIR_OUT)
4476 ret = gpiod_direction_output(desc,
4477 !!(dflags & GPIOD_FLAGS_BIT_DIR_VAL));
4478 else
4479 ret = gpiod_direction_input(desc);
4480
4481 return ret;
4482}
4483
4484/**
4485 * gpiod_get_index - obtain a GPIO from a multi-index GPIO function
4486 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4487 * @con_id: function within the GPIO consumer
4488 * @idx: index of the GPIO to obtain in the consumer
4489 * @flags: optional GPIO initialization flags
4490 *
4491 * This variant of gpiod_get() allows to access GPIOs other than the first
4492 * defined one for functions that define several GPIOs.
4493 *
4494 * Return a valid GPIO descriptor, -ENOENT if no GPIO has been assigned to the
4495 * requested function and/or index, or another IS_ERR() code if an error
4496 * occurred while trying to acquire the GPIO.
4497 */
4498struct gpio_desc *__must_check gpiod_get_index(struct device *dev,
4499 const char *con_id,
4500 unsigned int idx,
4501 enum gpiod_flags flags)
4502{
4503 unsigned long lookupflags = GPIO_LOOKUP_FLAGS_DEFAULT;
4504 struct gpio_desc *desc = NULL;
4505 int ret;
4506 /* Maybe we have a device name, maybe not */
4507 const char *devname = dev ? dev_name(dev) : "?";
4508
4509 dev_dbg(dev, "GPIO lookup for consumer %s\n", con_id);
4510
4511 if (dev) {
4512 /* Using device tree? */
4513 if (IS_ENABLED(CONFIG_OF) && dev->of_node) {
4514 dev_dbg(dev, "using device tree for GPIO lookup\n");
4515 desc = of_find_gpio(dev, con_id, idx, &lookupflags);
4516 } else if (ACPI_COMPANION(dev)) {
4517 dev_dbg(dev, "using ACPI for GPIO lookup\n");
4518 desc = acpi_find_gpio(dev, con_id, idx, &flags, &lookupflags);
4519 }
4520 }
4521
4522 /*
4523 * Either we are not using DT or ACPI, or their lookup did not return
4524 * a result. In that case, use platform lookup as a fallback.
4525 */
4526 if (!desc || desc == ERR_PTR(-ENOENT)) {
4527 dev_dbg(dev, "using lookup tables for GPIO lookup\n");
4528 desc = gpiod_find(dev, con_id, idx, &lookupflags);
4529 }
4530
4531 if (IS_ERR(desc)) {
4532 dev_dbg(dev, "No GPIO consumer %s found\n", con_id);
4533 return desc;
4534 }
4535
4536 /*
4537 * If a connection label was passed use that, else attempt to use
4538 * the device name as label
4539 */
4540 ret = gpiod_request(desc, con_id ? con_id : devname);
4541 if (ret < 0) {
4542 if (ret == -EBUSY && flags & GPIOD_FLAGS_BIT_NONEXCLUSIVE) {
4543 /*
4544 * This happens when there are several consumers for
4545 * the same GPIO line: we just return here without
4546 * further initialization. It is a bit if a hack.
4547 * This is necessary to support fixed regulators.
4548 *
4549 * FIXME: Make this more sane and safe.
4550 */
4551 dev_info(dev, "nonexclusive access to GPIO for %s\n",
4552 con_id ? con_id : devname);
4553 return desc;
4554 } else {
4555 return ERR_PTR(ret);
4556 }
4557 }
4558
4559 ret = gpiod_configure_flags(desc, con_id, lookupflags, flags);
4560 if (ret < 0) {
4561 dev_dbg(dev, "setup of GPIO %s failed\n", con_id);
4562 gpiod_put(desc);
4563 return ERR_PTR(ret);
4564 }
4565
4566 return desc;
4567}
4568EXPORT_SYMBOL_GPL(gpiod_get_index);
4569
4570/**
4571 * fwnode_get_named_gpiod - obtain a GPIO from firmware node
4572 * @fwnode: handle of the firmware node
4573 * @propname: name of the firmware property representing the GPIO
4574 * @index: index of the GPIO to obtain for the consumer
4575 * @dflags: GPIO initialization flags
4576 * @label: label to attach to the requested GPIO
4577 *
4578 * This function can be used for drivers that get their configuration
4579 * from opaque firmware.
4580 *
4581 * The function properly finds the corresponding GPIO using whatever is the
4582 * underlying firmware interface and then makes sure that the GPIO
4583 * descriptor is requested before it is returned to the caller.
4584 *
4585 * Returns:
4586 * On successful request the GPIO pin is configured in accordance with
4587 * provided @dflags.
4588 *
4589 * In case of error an ERR_PTR() is returned.
4590 */
4591struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode,
4592 const char *propname, int index,
4593 enum gpiod_flags dflags,
4594 const char *label)
4595{
4596 unsigned long lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
4597 struct gpio_desc *desc = ERR_PTR(-ENODEV);
4598 int ret;
4599
4600 if (!fwnode)
4601 return ERR_PTR(-EINVAL);
4602
4603 if (is_of_node(fwnode)) {
4604 desc = gpiod_get_from_of_node(to_of_node(fwnode),
4605 propname, index,
4606 dflags,
4607 label);
4608 return desc;
4609 } else if (is_acpi_node(fwnode)) {
4610 struct acpi_gpio_info info;
4611
4612 desc = acpi_node_get_gpiod(fwnode, propname, index, &info);
4613 if (IS_ERR(desc))
4614 return desc;
4615
4616 acpi_gpio_update_gpiod_flags(&dflags, &info);
4617 acpi_gpio_update_gpiod_lookup_flags(&lflags, &info);
4618 }
4619
4620 /* Currently only ACPI takes this path */
4621 ret = gpiod_request(desc, label);
4622 if (ret)
4623 return ERR_PTR(ret);
4624
4625 ret = gpiod_configure_flags(desc, propname, lflags, dflags);
4626 if (ret < 0) {
4627 gpiod_put(desc);
4628 return ERR_PTR(ret);
4629 }
4630
4631 return desc;
4632}
4633EXPORT_SYMBOL_GPL(fwnode_get_named_gpiod);
4634
4635/**
4636 * gpiod_get_index_optional - obtain an optional GPIO from a multi-index GPIO
4637 * function
4638 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4639 * @con_id: function within the GPIO consumer
4640 * @index: index of the GPIO to obtain in the consumer
4641 * @flags: optional GPIO initialization flags
4642 *
4643 * This is equivalent to gpiod_get_index(), except that when no GPIO with the
4644 * specified index was assigned to the requested function it will return NULL.
4645 * This is convenient for drivers that need to handle optional GPIOs.
4646 */
4647struct gpio_desc *__must_check gpiod_get_index_optional(struct device *dev,
4648 const char *con_id,
4649 unsigned int index,
4650 enum gpiod_flags flags)
4651{
4652 struct gpio_desc *desc;
4653
4654 desc = gpiod_get_index(dev, con_id, index, flags);
4655 if (IS_ERR(desc)) {
4656 if (PTR_ERR(desc) == -ENOENT)
4657 return NULL;
4658 }
4659
4660 return desc;
4661}
4662EXPORT_SYMBOL_GPL(gpiod_get_index_optional);
4663
4664/**
4665 * gpiod_hog - Hog the specified GPIO desc given the provided flags
4666 * @desc: gpio whose value will be assigned
4667 * @name: gpio line name
4668 * @lflags: bitmask of gpio_lookup_flags GPIO_* values - returned from
4669 * of_find_gpio() or of_get_gpio_hog()
4670 * @dflags: gpiod_flags - optional GPIO initialization flags
4671 */
4672int gpiod_hog(struct gpio_desc *desc, const char *name,
4673 unsigned long lflags, enum gpiod_flags dflags)
4674{
4675 struct gpio_chip *chip;
4676 struct gpio_desc *local_desc;
4677 int hwnum;
4678 int ret;
4679
4680 chip = gpiod_to_chip(desc);
4681 hwnum = gpio_chip_hwgpio(desc);
4682
4683 local_desc = gpiochip_request_own_desc(chip, hwnum, name,
4684 lflags, dflags);
4685 if (IS_ERR(local_desc)) {
4686 ret = PTR_ERR(local_desc);
4687 pr_err("requesting hog GPIO %s (chip %s, offset %d) failed, %d\n",
4688 name, chip->label, hwnum, ret);
4689 return ret;
4690 }
4691
4692 /* Mark GPIO as hogged so it can be identified and removed later */
4693 set_bit(FLAG_IS_HOGGED, &desc->flags);
4694
4695 pr_info("GPIO line %d (%s) hogged as %s%s\n",
4696 desc_to_gpio(desc), name,
4697 (dflags&GPIOD_FLAGS_BIT_DIR_OUT) ? "output" : "input",
4698 (dflags&GPIOD_FLAGS_BIT_DIR_OUT) ?
4699 (dflags&GPIOD_FLAGS_BIT_DIR_VAL) ? "/high" : "/low":"");
4700
4701 return 0;
4702}
4703
4704/**
4705 * gpiochip_free_hogs - Scan gpio-controller chip and release GPIO hog
4706 * @chip: gpio chip to act on
4707 */
4708static void gpiochip_free_hogs(struct gpio_chip *chip)
4709{
4710 int id;
4711
4712 for (id = 0; id < chip->ngpio; id++) {
4713 if (test_bit(FLAG_IS_HOGGED, &chip->gpiodev->descs[id].flags))
4714 gpiochip_free_own_desc(&chip->gpiodev->descs[id]);
4715 }
4716}
4717
4718/**
4719 * gpiod_get_array - obtain multiple GPIOs from a multi-index GPIO function
4720 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4721 * @con_id: function within the GPIO consumer
4722 * @flags: optional GPIO initialization flags
4723 *
4724 * This function acquires all the GPIOs defined under a given function.
4725 *
4726 * Return a struct gpio_descs containing an array of descriptors, -ENOENT if
4727 * no GPIO has been assigned to the requested function, or another IS_ERR()
4728 * code if an error occurred while trying to acquire the GPIOs.
4729 */
4730struct gpio_descs *__must_check gpiod_get_array(struct device *dev,
4731 const char *con_id,
4732 enum gpiod_flags flags)
4733{
4734 struct gpio_desc *desc;
4735 struct gpio_descs *descs;
4736 struct gpio_array *array_info = NULL;
4737 struct gpio_chip *chip;
4738 int count, bitmap_size;
4739
4740 count = gpiod_count(dev, con_id);
4741 if (count < 0)
4742 return ERR_PTR(count);
4743
4744 descs = kzalloc(struct_size(descs, desc, count), GFP_KERNEL);
4745 if (!descs)
4746 return ERR_PTR(-ENOMEM);
4747
4748 for (descs->ndescs = 0; descs->ndescs < count; ) {
4749 desc = gpiod_get_index(dev, con_id, descs->ndescs, flags);
4750 if (IS_ERR(desc)) {
4751 gpiod_put_array(descs);
4752 return ERR_CAST(desc);
4753 }
4754
4755 descs->desc[descs->ndescs] = desc;
4756
4757 chip = gpiod_to_chip(desc);
4758 /*
4759 * If pin hardware number of array member 0 is also 0, select
4760 * its chip as a candidate for fast bitmap processing path.
4761 */
4762 if (descs->ndescs == 0 && gpio_chip_hwgpio(desc) == 0) {
4763 struct gpio_descs *array;
4764
4765 bitmap_size = BITS_TO_LONGS(chip->ngpio > count ?
4766 chip->ngpio : count);
4767
4768 array = kzalloc(struct_size(descs, desc, count) +
4769 struct_size(array_info, invert_mask,
4770 3 * bitmap_size), GFP_KERNEL);
4771 if (!array) {
4772 gpiod_put_array(descs);
4773 return ERR_PTR(-ENOMEM);
4774 }
4775
4776 memcpy(array, descs,
4777 struct_size(descs, desc, descs->ndescs + 1));
4778 kfree(descs);
4779
4780 descs = array;
4781 array_info = (void *)(descs->desc + count);
4782 array_info->get_mask = array_info->invert_mask +
4783 bitmap_size;
4784 array_info->set_mask = array_info->get_mask +
4785 bitmap_size;
4786
4787 array_info->desc = descs->desc;
4788 array_info->size = count;
4789 array_info->chip = chip;
4790 bitmap_set(array_info->get_mask, descs->ndescs,
4791 count - descs->ndescs);
4792 bitmap_set(array_info->set_mask, descs->ndescs,
4793 count - descs->ndescs);
4794 descs->info = array_info;
4795 }
4796 /* Unmark array members which don't belong to the 'fast' chip */
4797 if (array_info && array_info->chip != chip) {
4798 __clear_bit(descs->ndescs, array_info->get_mask);
4799 __clear_bit(descs->ndescs, array_info->set_mask);
4800 }
4801 /*
4802 * Detect array members which belong to the 'fast' chip
4803 * but their pins are not in hardware order.
4804 */
4805 else if (array_info &&
4806 gpio_chip_hwgpio(desc) != descs->ndescs) {
4807 /*
4808 * Don't use fast path if all array members processed so
4809 * far belong to the same chip as this one but its pin
4810 * hardware number is different from its array index.
4811 */
4812 if (bitmap_full(array_info->get_mask, descs->ndescs)) {
4813 array_info = NULL;
4814 } else {
4815 __clear_bit(descs->ndescs,
4816 array_info->get_mask);
4817 __clear_bit(descs->ndescs,
4818 array_info->set_mask);
4819 }
4820 } else if (array_info) {
4821 /* Exclude open drain or open source from fast output */
4822 if (gpiochip_line_is_open_drain(chip, descs->ndescs) ||
4823 gpiochip_line_is_open_source(chip, descs->ndescs))
4824 __clear_bit(descs->ndescs,
4825 array_info->set_mask);
4826 /* Identify 'fast' pins which require invertion */
4827 if (gpiod_is_active_low(desc))
4828 __set_bit(descs->ndescs,
4829 array_info->invert_mask);
4830 }
4831
4832 descs->ndescs++;
4833 }
4834 if (array_info)
4835 dev_dbg(dev,
4836 "GPIO array info: chip=%s, size=%d, get_mask=%lx, set_mask=%lx, invert_mask=%lx\n",
4837 array_info->chip->label, array_info->size,
4838 *array_info->get_mask, *array_info->set_mask,
4839 *array_info->invert_mask);
4840 return descs;
4841}
4842EXPORT_SYMBOL_GPL(gpiod_get_array);
4843
4844/**
4845 * gpiod_get_array_optional - obtain multiple GPIOs from a multi-index GPIO
4846 * function
4847 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4848 * @con_id: function within the GPIO consumer
4849 * @flags: optional GPIO initialization flags
4850 *
4851 * This is equivalent to gpiod_get_array(), except that when no GPIO was
4852 * assigned to the requested function it will return NULL.
4853 */
4854struct gpio_descs *__must_check gpiod_get_array_optional(struct device *dev,
4855 const char *con_id,
4856 enum gpiod_flags flags)
4857{
4858 struct gpio_descs *descs;
4859
4860 descs = gpiod_get_array(dev, con_id, flags);
4861 if (IS_ERR(descs) && (PTR_ERR(descs) == -ENOENT))
4862 return NULL;
4863
4864 return descs;
4865}
4866EXPORT_SYMBOL_GPL(gpiod_get_array_optional);
4867
4868/**
4869 * gpiod_put - dispose of a GPIO descriptor
4870 * @desc: GPIO descriptor to dispose of
4871 *
4872 * No descriptor can be used after gpiod_put() has been called on it.
4873 */
4874void gpiod_put(struct gpio_desc *desc)
4875{
4876 if (desc)
4877 gpiod_free(desc);
4878}
4879EXPORT_SYMBOL_GPL(gpiod_put);
4880
4881/**
4882 * gpiod_put_array - dispose of multiple GPIO descriptors
4883 * @descs: struct gpio_descs containing an array of descriptors
4884 */
4885void gpiod_put_array(struct gpio_descs *descs)
4886{
4887 unsigned int i;
4888
4889 for (i = 0; i < descs->ndescs; i++)
4890 gpiod_put(descs->desc[i]);
4891
4892 kfree(descs);
4893}
4894EXPORT_SYMBOL_GPL(gpiod_put_array);
4895
4896static int __init gpiolib_dev_init(void)
4897{
4898 int ret;
4899
4900 /* Register GPIO sysfs bus */
4901 ret = bus_register(&gpio_bus_type);
4902 if (ret < 0) {
4903 pr_err("gpiolib: could not register GPIO bus type\n");
4904 return ret;
4905 }
4906
4907 ret = alloc_chrdev_region(&gpio_devt, 0, GPIO_DEV_MAX, "gpiochip");
4908 if (ret < 0) {
4909 pr_err("gpiolib: failed to allocate char dev region\n");
4910 bus_unregister(&gpio_bus_type);
4911 } else {
4912 gpiolib_initialized = true;
4913 gpiochip_setup_devs();
4914 }
4915 return ret;
4916}
4917core_initcall(gpiolib_dev_init);
4918
4919#ifdef CONFIG_DEBUG_FS
4920
4921static void gpiolib_dbg_show(struct seq_file *s, struct gpio_device *gdev)
4922{
4923 unsigned i;
4924 struct gpio_chip *chip = gdev->chip;
4925 unsigned gpio = gdev->base;
4926 struct gpio_desc *gdesc = &gdev->descs[0];
4927 bool is_out;
4928 bool is_irq;
4929 bool active_low;
4930
4931 for (i = 0; i < gdev->ngpio; i++, gpio++, gdesc++) {
4932 if (!test_bit(FLAG_REQUESTED, &gdesc->flags)) {
4933 if (gdesc->name) {
4934 seq_printf(s, " gpio-%-3d (%-20.20s)\n",
4935 gpio, gdesc->name);
4936 }
4937 continue;
4938 }
4939
4940 gpiod_get_direction(gdesc);
4941 is_out = test_bit(FLAG_IS_OUT, &gdesc->flags);
4942 is_irq = test_bit(FLAG_USED_AS_IRQ, &gdesc->flags);
4943 active_low = test_bit(FLAG_ACTIVE_LOW, &gdesc->flags);
4944 seq_printf(s, " gpio-%-3d (%-20.20s|%-20.20s) %s %s %s%s",
4945 gpio, gdesc->name ? gdesc->name : "", gdesc->label,
4946 is_out ? "out" : "in ",
4947 chip->get ? (chip->get(chip, i) ? "hi" : "lo") : "? ",
4948 is_irq ? "IRQ " : "",
4949 active_low ? "ACTIVE LOW" : "");
4950 seq_printf(s, "\n");
4951 }
4952}
4953
4954static void *gpiolib_seq_start(struct seq_file *s, loff_t *pos)
4955{
4956 unsigned long flags;
4957 struct gpio_device *gdev = NULL;
4958 loff_t index = *pos;
4959
4960 s->private = "";
4961
4962 spin_lock_irqsave(&gpio_lock, flags);
4963 list_for_each_entry(gdev, &gpio_devices, list)
4964 if (index-- == 0) {
4965 spin_unlock_irqrestore(&gpio_lock, flags);
4966 return gdev;
4967 }
4968 spin_unlock_irqrestore(&gpio_lock, flags);
4969
4970 return NULL;
4971}
4972
4973static void *gpiolib_seq_next(struct seq_file *s, void *v, loff_t *pos)
4974{
4975 unsigned long flags;
4976 struct gpio_device *gdev = v;
4977 void *ret = NULL;
4978
4979 spin_lock_irqsave(&gpio_lock, flags);
4980 if (list_is_last(&gdev->list, &gpio_devices))
4981 ret = NULL;
4982 else
4983 ret = list_entry(gdev->list.next, struct gpio_device, list);
4984 spin_unlock_irqrestore(&gpio_lock, flags);
4985
4986 s->private = "\n";
4987 ++*pos;
4988
4989 return ret;
4990}
4991
4992static void gpiolib_seq_stop(struct seq_file *s, void *v)
4993{
4994}
4995
4996static int gpiolib_seq_show(struct seq_file *s, void *v)
4997{
4998 struct gpio_device *gdev = v;
4999 struct gpio_chip *chip = gdev->chip;
5000 struct device *parent;
5001
5002 if (!chip) {
5003 seq_printf(s, "%s%s: (dangling chip)", (char *)s->private,
5004 dev_name(&gdev->dev));
5005 return 0;
5006 }
5007
5008 seq_printf(s, "%s%s: GPIOs %d-%d", (char *)s->private,
5009 dev_name(&gdev->dev),
5010 gdev->base, gdev->base + gdev->ngpio - 1);
5011 parent = chip->parent;
5012 if (parent)
5013 seq_printf(s, ", parent: %s/%s",
5014 parent->bus ? parent->bus->name : "no-bus",
5015 dev_name(parent));
5016 if (chip->label)
5017 seq_printf(s, ", %s", chip->label);
5018 if (chip->can_sleep)
5019 seq_printf(s, ", can sleep");
5020 seq_printf(s, ":\n");
5021
5022 if (chip->dbg_show)
5023 chip->dbg_show(s, chip);
5024 else
5025 gpiolib_dbg_show(s, gdev);
5026
5027 return 0;
5028}
5029
5030static const struct seq_operations gpiolib_seq_ops = {
5031 .start = gpiolib_seq_start,
5032 .next = gpiolib_seq_next,
5033 .stop = gpiolib_seq_stop,
5034 .show = gpiolib_seq_show,
5035};
5036
5037static int gpiolib_open(struct inode *inode, struct file *file)
5038{
5039 return seq_open(file, &gpiolib_seq_ops);
5040}
5041
5042static const struct file_operations gpiolib_operations = {
5043 .owner = THIS_MODULE,
5044 .open = gpiolib_open,
5045 .read = seq_read,
5046 .llseek = seq_lseek,
5047 .release = seq_release,
5048};
5049
5050static int __init gpiolib_debugfs_init(void)
5051{
5052 /* /sys/kernel/debug/gpio */
5053 debugfs_create_file("gpio", S_IFREG | S_IRUGO, NULL, NULL,
5054 &gpiolib_operations);
5055 return 0;
5056}
5057subsys_initcall(gpiolib_debugfs_init);
5058
5059#endif /* DEBUG_FS */