Loading...
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/fs.h>
21#include <linux/compat.h>
22#include <linux/file.h>
23#include <uapi/linux/gpio.h>
24
25#include "gpiolib.h"
26#include "gpiolib-of.h"
27#include "gpiolib-acpi.h"
28#include "gpiolib-cdev.h"
29#include "gpiolib-sysfs.h"
30
31#define CREATE_TRACE_POINTS
32#include <trace/events/gpio.h>
33
34/* Implementation infrastructure for GPIO interfaces.
35 *
36 * The GPIO programming interface allows for inlining speed-critical
37 * get/set operations for common cases, so that access to SOC-integrated
38 * GPIOs can sometimes cost only an instruction or two per bit.
39 */
40
41
42/* When debugging, extend minimal trust to callers and platform code.
43 * Also emit diagnostic messages that may help initial bringup, when
44 * board setup or driver bugs are most common.
45 *
46 * Otherwise, minimize overhead in what may be bitbanging codepaths.
47 */
48#ifdef DEBUG
49#define extra_checks 1
50#else
51#define extra_checks 0
52#endif
53
54/* Device and char device-related information */
55static DEFINE_IDA(gpio_ida);
56static dev_t gpio_devt;
57#define GPIO_DEV_MAX 256 /* 256 GPIO chip devices supported */
58static struct bus_type gpio_bus_type = {
59 .name = "gpio",
60};
61
62/*
63 * Number of GPIOs to use for the fast path in set array
64 */
65#define FASTPATH_NGPIO CONFIG_GPIOLIB_FASTPATH_LIMIT
66
67/* gpio_lock prevents conflicts during gpio_desc[] table updates.
68 * While any GPIO is requested, its gpio_chip is not removable;
69 * each GPIO's "requested" flag serves as a lock and refcount.
70 */
71DEFINE_SPINLOCK(gpio_lock);
72
73static DEFINE_MUTEX(gpio_lookup_lock);
74static LIST_HEAD(gpio_lookup_list);
75LIST_HEAD(gpio_devices);
76
77static DEFINE_MUTEX(gpio_machine_hogs_mutex);
78static LIST_HEAD(gpio_machine_hogs);
79
80static void gpiochip_free_hogs(struct gpio_chip *gc);
81static int gpiochip_add_irqchip(struct gpio_chip *gc,
82 struct lock_class_key *lock_key,
83 struct lock_class_key *request_key);
84static void gpiochip_irqchip_remove(struct gpio_chip *gc);
85static int gpiochip_irqchip_init_hw(struct gpio_chip *gc);
86static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gc);
87static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gc);
88
89static bool gpiolib_initialized;
90
91static inline void desc_set_label(struct gpio_desc *d, const char *label)
92{
93 d->label = label;
94}
95
96/**
97 * gpio_to_desc - Convert a GPIO number to its descriptor
98 * @gpio: global GPIO number
99 *
100 * Returns:
101 * The GPIO descriptor associated with the given GPIO, or %NULL if no GPIO
102 * with the given number exists in the system.
103 */
104struct gpio_desc *gpio_to_desc(unsigned gpio)
105{
106 struct gpio_device *gdev;
107 unsigned long flags;
108
109 spin_lock_irqsave(&gpio_lock, flags);
110
111 list_for_each_entry(gdev, &gpio_devices, list) {
112 if (gdev->base <= gpio &&
113 gdev->base + gdev->ngpio > gpio) {
114 spin_unlock_irqrestore(&gpio_lock, flags);
115 return &gdev->descs[gpio - gdev->base];
116 }
117 }
118
119 spin_unlock_irqrestore(&gpio_lock, flags);
120
121 if (!gpio_is_valid(gpio))
122 WARN(1, "invalid GPIO %d\n", gpio);
123
124 return NULL;
125}
126EXPORT_SYMBOL_GPL(gpio_to_desc);
127
128/**
129 * gpiochip_get_desc - get the GPIO descriptor corresponding to the given
130 * hardware number for this chip
131 * @gc: GPIO chip
132 * @hwnum: hardware number of the GPIO for this chip
133 *
134 * Returns:
135 * A pointer to the GPIO descriptor or ``ERR_PTR(-EINVAL)`` if no GPIO exists
136 * in the given chip for the specified hardware number.
137 */
138struct gpio_desc *gpiochip_get_desc(struct gpio_chip *gc,
139 unsigned int hwnum)
140{
141 struct gpio_device *gdev = gc->gpiodev;
142
143 if (hwnum >= gdev->ngpio)
144 return ERR_PTR(-EINVAL);
145
146 return &gdev->descs[hwnum];
147}
148EXPORT_SYMBOL_GPL(gpiochip_get_desc);
149
150/**
151 * desc_to_gpio - convert a GPIO descriptor to the integer namespace
152 * @desc: GPIO descriptor
153 *
154 * This should disappear in the future but is needed since we still
155 * use GPIO numbers for error messages and sysfs nodes.
156 *
157 * Returns:
158 * The global GPIO number for the GPIO specified by its descriptor.
159 */
160int desc_to_gpio(const struct gpio_desc *desc)
161{
162 return desc->gdev->base + (desc - &desc->gdev->descs[0]);
163}
164EXPORT_SYMBOL_GPL(desc_to_gpio);
165
166
167/**
168 * gpiod_to_chip - Return the GPIO chip to which a GPIO descriptor belongs
169 * @desc: descriptor to return the chip of
170 */
171struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc)
172{
173 if (!desc || !desc->gdev)
174 return NULL;
175 return desc->gdev->chip;
176}
177EXPORT_SYMBOL_GPL(gpiod_to_chip);
178
179/* dynamic allocation of GPIOs, e.g. on a hotplugged device */
180static int gpiochip_find_base(int ngpio)
181{
182 struct gpio_device *gdev;
183 int base = ARCH_NR_GPIOS - ngpio;
184
185 list_for_each_entry_reverse(gdev, &gpio_devices, list) {
186 /* found a free space? */
187 if (gdev->base + gdev->ngpio <= base)
188 break;
189 else
190 /* nope, check the space right before the chip */
191 base = gdev->base - ngpio;
192 }
193
194 if (gpio_is_valid(base)) {
195 pr_debug("%s: found new base at %d\n", __func__, base);
196 return base;
197 } else {
198 pr_err("%s: cannot find free range\n", __func__);
199 return -ENOSPC;
200 }
201}
202
203/**
204 * gpiod_get_direction - return the current direction of a GPIO
205 * @desc: GPIO to get the direction of
206 *
207 * Returns 0 for output, 1 for input, or an error code in case of error.
208 *
209 * This function may sleep if gpiod_cansleep() is true.
210 */
211int gpiod_get_direction(struct gpio_desc *desc)
212{
213 struct gpio_chip *gc;
214 unsigned offset;
215 int ret;
216
217 gc = gpiod_to_chip(desc);
218 offset = gpio_chip_hwgpio(desc);
219
220 /*
221 * Open drain emulation using input mode may incorrectly report
222 * input here, fix that up.
223 */
224 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags) &&
225 test_bit(FLAG_IS_OUT, &desc->flags))
226 return 0;
227
228 if (!gc->get_direction)
229 return -ENOTSUPP;
230
231 ret = gc->get_direction(gc, offset);
232 if (ret < 0)
233 return ret;
234
235 /* GPIOF_DIR_IN or other positive, otherwise GPIOF_DIR_OUT */
236 if (ret > 0)
237 ret = 1;
238
239 assign_bit(FLAG_IS_OUT, &desc->flags, !ret);
240
241 return ret;
242}
243EXPORT_SYMBOL_GPL(gpiod_get_direction);
244
245/*
246 * Add a new chip to the global chips list, keeping the list of chips sorted
247 * by range(means [base, base + ngpio - 1]) order.
248 *
249 * Return -EBUSY if the new chip overlaps with some other chip's integer
250 * space.
251 */
252static int gpiodev_add_to_list(struct gpio_device *gdev)
253{
254 struct gpio_device *prev, *next;
255
256 if (list_empty(&gpio_devices)) {
257 /* initial entry in list */
258 list_add_tail(&gdev->list, &gpio_devices);
259 return 0;
260 }
261
262 next = list_entry(gpio_devices.next, struct gpio_device, list);
263 if (gdev->base + gdev->ngpio <= next->base) {
264 /* add before first entry */
265 list_add(&gdev->list, &gpio_devices);
266 return 0;
267 }
268
269 prev = list_entry(gpio_devices.prev, struct gpio_device, list);
270 if (prev->base + prev->ngpio <= gdev->base) {
271 /* add behind last entry */
272 list_add_tail(&gdev->list, &gpio_devices);
273 return 0;
274 }
275
276 list_for_each_entry_safe(prev, next, &gpio_devices, list) {
277 /* at the end of the list */
278 if (&next->list == &gpio_devices)
279 break;
280
281 /* add between prev and next */
282 if (prev->base + prev->ngpio <= gdev->base
283 && gdev->base + gdev->ngpio <= next->base) {
284 list_add(&gdev->list, &prev->list);
285 return 0;
286 }
287 }
288
289 dev_err(&gdev->dev, "GPIO integer space overlap, cannot add chip\n");
290 return -EBUSY;
291}
292
293/*
294 * Convert a GPIO name to its descriptor
295 * Note that there is no guarantee that GPIO names are globally unique!
296 * Hence this function will return, if it exists, a reference to the first GPIO
297 * line found that matches the given name.
298 */
299static struct gpio_desc *gpio_name_to_desc(const char * const name)
300{
301 struct gpio_device *gdev;
302 unsigned long flags;
303
304 if (!name)
305 return NULL;
306
307 spin_lock_irqsave(&gpio_lock, flags);
308
309 list_for_each_entry(gdev, &gpio_devices, list) {
310 int i;
311
312 for (i = 0; i != gdev->ngpio; ++i) {
313 struct gpio_desc *desc = &gdev->descs[i];
314
315 if (!desc->name)
316 continue;
317
318 if (!strcmp(desc->name, name)) {
319 spin_unlock_irqrestore(&gpio_lock, flags);
320 return desc;
321 }
322 }
323 }
324
325 spin_unlock_irqrestore(&gpio_lock, flags);
326
327 return NULL;
328}
329
330/*
331 * Take the names from gc->names and assign them to their GPIO descriptors.
332 * Warn if a name is already used for a GPIO line on a different GPIO chip.
333 *
334 * Note that:
335 * 1. Non-unique names are still accepted,
336 * 2. Name collisions within the same GPIO chip are not reported.
337 */
338static int gpiochip_set_desc_names(struct gpio_chip *gc)
339{
340 struct gpio_device *gdev = gc->gpiodev;
341 int i;
342
343 if (!gc->names)
344 return 0;
345
346 /* First check all names if they are unique */
347 for (i = 0; i != gc->ngpio; ++i) {
348 struct gpio_desc *gpio;
349
350 gpio = gpio_name_to_desc(gc->names[i]);
351 if (gpio)
352 dev_warn(&gdev->dev,
353 "Detected name collision for GPIO name '%s'\n",
354 gc->names[i]);
355 }
356
357 /* Then add all names to the GPIO descriptors */
358 for (i = 0; i != gc->ngpio; ++i)
359 gdev->descs[i].name = gc->names[i];
360
361 return 0;
362}
363
364static unsigned long *gpiochip_allocate_mask(struct gpio_chip *gc)
365{
366 unsigned long *p;
367
368 p = bitmap_alloc(gc->ngpio, GFP_KERNEL);
369 if (!p)
370 return NULL;
371
372 /* Assume by default all GPIOs are valid */
373 bitmap_fill(p, gc->ngpio);
374
375 return p;
376}
377
378static int gpiochip_alloc_valid_mask(struct gpio_chip *gc)
379{
380 if (!(of_gpio_need_valid_mask(gc) || gc->init_valid_mask))
381 return 0;
382
383 gc->valid_mask = gpiochip_allocate_mask(gc);
384 if (!gc->valid_mask)
385 return -ENOMEM;
386
387 return 0;
388}
389
390static int gpiochip_init_valid_mask(struct gpio_chip *gc)
391{
392 if (gc->init_valid_mask)
393 return gc->init_valid_mask(gc,
394 gc->valid_mask,
395 gc->ngpio);
396
397 return 0;
398}
399
400static void gpiochip_free_valid_mask(struct gpio_chip *gc)
401{
402 bitmap_free(gc->valid_mask);
403 gc->valid_mask = NULL;
404}
405
406static int gpiochip_add_pin_ranges(struct gpio_chip *gc)
407{
408 if (gc->add_pin_ranges)
409 return gc->add_pin_ranges(gc);
410
411 return 0;
412}
413
414bool gpiochip_line_is_valid(const struct gpio_chip *gc,
415 unsigned int offset)
416{
417 /* No mask means all valid */
418 if (likely(!gc->valid_mask))
419 return true;
420 return test_bit(offset, gc->valid_mask);
421}
422EXPORT_SYMBOL_GPL(gpiochip_line_is_valid);
423
424static void gpiodevice_release(struct device *dev)
425{
426 struct gpio_device *gdev = dev_get_drvdata(dev);
427
428 list_del(&gdev->list);
429 ida_simple_remove(&gpio_ida, gdev->id);
430 kfree_const(gdev->label);
431 kfree(gdev->descs);
432 kfree(gdev);
433}
434
435static int gpiochip_setup_dev(struct gpio_device *gdev)
436{
437 int ret;
438
439 ret = gpiolib_cdev_register(gdev, gpio_devt);
440 if (ret)
441 return ret;
442
443 ret = gpiochip_sysfs_register(gdev);
444 if (ret)
445 goto err_remove_device;
446
447 /* From this point, the .release() function cleans up gpio_device */
448 gdev->dev.release = gpiodevice_release;
449 dev_dbg(&gdev->dev, "registered GPIOs %d to %d on %s\n", gdev->base,
450 gdev->base + gdev->ngpio - 1, gdev->chip->label ? : "generic");
451
452 return 0;
453
454err_remove_device:
455 gpiolib_cdev_unregister(gdev);
456 return ret;
457}
458
459static void gpiochip_machine_hog(struct gpio_chip *gc, struct gpiod_hog *hog)
460{
461 struct gpio_desc *desc;
462 int rv;
463
464 desc = gpiochip_get_desc(gc, hog->chip_hwnum);
465 if (IS_ERR(desc)) {
466 chip_err(gc, "%s: unable to get GPIO desc: %ld\n", __func__,
467 PTR_ERR(desc));
468 return;
469 }
470
471 if (test_bit(FLAG_IS_HOGGED, &desc->flags))
472 return;
473
474 rv = gpiod_hog(desc, hog->line_name, hog->lflags, hog->dflags);
475 if (rv)
476 gpiod_err(desc, "%s: unable to hog GPIO line (%s:%u): %d\n",
477 __func__, gc->label, hog->chip_hwnum, rv);
478}
479
480static void machine_gpiochip_add(struct gpio_chip *gc)
481{
482 struct gpiod_hog *hog;
483
484 mutex_lock(&gpio_machine_hogs_mutex);
485
486 list_for_each_entry(hog, &gpio_machine_hogs, list) {
487 if (!strcmp(gc->label, hog->chip_label))
488 gpiochip_machine_hog(gc, hog);
489 }
490
491 mutex_unlock(&gpio_machine_hogs_mutex);
492}
493
494static void gpiochip_setup_devs(void)
495{
496 struct gpio_device *gdev;
497 int ret;
498
499 list_for_each_entry(gdev, &gpio_devices, list) {
500 ret = gpiochip_setup_dev(gdev);
501 if (ret)
502 dev_err(&gdev->dev,
503 "Failed to initialize gpio device (%d)\n", ret);
504 }
505}
506
507int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data,
508 struct lock_class_key *lock_key,
509 struct lock_class_key *request_key)
510{
511 unsigned long flags;
512 int ret = 0;
513 unsigned i;
514 int base = gc->base;
515 struct gpio_device *gdev;
516
517 /*
518 * First: allocate and populate the internal stat container, and
519 * set up the struct device.
520 */
521 gdev = kzalloc(sizeof(*gdev), GFP_KERNEL);
522 if (!gdev)
523 return -ENOMEM;
524 gdev->dev.bus = &gpio_bus_type;
525 gdev->chip = gc;
526 gc->gpiodev = gdev;
527 if (gc->parent) {
528 gdev->dev.parent = gc->parent;
529 gdev->dev.of_node = gc->parent->of_node;
530 }
531
532#ifdef CONFIG_OF_GPIO
533 /* If the gpiochip has an assigned OF node this takes precedence */
534 if (gc->of_node)
535 gdev->dev.of_node = gc->of_node;
536 else
537 gc->of_node = gdev->dev.of_node;
538#endif
539
540 gdev->id = ida_simple_get(&gpio_ida, 0, 0, GFP_KERNEL);
541 if (gdev->id < 0) {
542 ret = gdev->id;
543 goto err_free_gdev;
544 }
545 dev_set_name(&gdev->dev, GPIOCHIP_NAME "%d", gdev->id);
546 device_initialize(&gdev->dev);
547 dev_set_drvdata(&gdev->dev, gdev);
548 if (gc->parent && gc->parent->driver)
549 gdev->owner = gc->parent->driver->owner;
550 else if (gc->owner)
551 /* TODO: remove chip->owner */
552 gdev->owner = gc->owner;
553 else
554 gdev->owner = THIS_MODULE;
555
556 gdev->descs = kcalloc(gc->ngpio, sizeof(gdev->descs[0]), GFP_KERNEL);
557 if (!gdev->descs) {
558 ret = -ENOMEM;
559 goto err_free_ida;
560 }
561
562 if (gc->ngpio == 0) {
563 chip_err(gc, "tried to insert a GPIO chip with zero lines\n");
564 ret = -EINVAL;
565 goto err_free_descs;
566 }
567
568 if (gc->ngpio > FASTPATH_NGPIO)
569 chip_warn(gc, "line cnt %u is greater than fast path cnt %u\n",
570 gc->ngpio, FASTPATH_NGPIO);
571
572 gdev->label = kstrdup_const(gc->label ?: "unknown", GFP_KERNEL);
573 if (!gdev->label) {
574 ret = -ENOMEM;
575 goto err_free_descs;
576 }
577
578 gdev->ngpio = gc->ngpio;
579 gdev->data = data;
580
581 spin_lock_irqsave(&gpio_lock, flags);
582
583 /*
584 * TODO: this allocates a Linux GPIO number base in the global
585 * GPIO numberspace for this chip. In the long run we want to
586 * get *rid* of this numberspace and use only descriptors, but
587 * it may be a pipe dream. It will not happen before we get rid
588 * of the sysfs interface anyways.
589 */
590 if (base < 0) {
591 base = gpiochip_find_base(gc->ngpio);
592 if (base < 0) {
593 ret = base;
594 spin_unlock_irqrestore(&gpio_lock, flags);
595 goto err_free_label;
596 }
597 /*
598 * TODO: it should not be necessary to reflect the assigned
599 * base outside of the GPIO subsystem. Go over drivers and
600 * see if anyone makes use of this, else drop this and assign
601 * a poison instead.
602 */
603 gc->base = base;
604 }
605 gdev->base = base;
606
607 ret = gpiodev_add_to_list(gdev);
608 if (ret) {
609 spin_unlock_irqrestore(&gpio_lock, flags);
610 goto err_free_label;
611 }
612
613 for (i = 0; i < gc->ngpio; i++)
614 gdev->descs[i].gdev = gdev;
615
616 spin_unlock_irqrestore(&gpio_lock, flags);
617
618 BLOCKING_INIT_NOTIFIER_HEAD(&gdev->notifier);
619
620#ifdef CONFIG_PINCTRL
621 INIT_LIST_HEAD(&gdev->pin_ranges);
622#endif
623
624 ret = gpiochip_set_desc_names(gc);
625 if (ret)
626 goto err_remove_from_list;
627
628 ret = gpiochip_alloc_valid_mask(gc);
629 if (ret)
630 goto err_remove_from_list;
631
632 ret = of_gpiochip_add(gc);
633 if (ret)
634 goto err_free_gpiochip_mask;
635
636 ret = gpiochip_init_valid_mask(gc);
637 if (ret)
638 goto err_remove_of_chip;
639
640 for (i = 0; i < gc->ngpio; i++) {
641 struct gpio_desc *desc = &gdev->descs[i];
642
643 if (gc->get_direction && gpiochip_line_is_valid(gc, i)) {
644 assign_bit(FLAG_IS_OUT,
645 &desc->flags, !gc->get_direction(gc, i));
646 } else {
647 assign_bit(FLAG_IS_OUT,
648 &desc->flags, !gc->direction_input);
649 }
650 }
651
652 ret = gpiochip_add_pin_ranges(gc);
653 if (ret)
654 goto err_remove_of_chip;
655
656 acpi_gpiochip_add(gc);
657
658 machine_gpiochip_add(gc);
659
660 ret = gpiochip_irqchip_init_valid_mask(gc);
661 if (ret)
662 goto err_remove_acpi_chip;
663
664 ret = gpiochip_irqchip_init_hw(gc);
665 if (ret)
666 goto err_remove_acpi_chip;
667
668 ret = gpiochip_add_irqchip(gc, lock_key, request_key);
669 if (ret)
670 goto err_remove_irqchip_mask;
671
672 /*
673 * By first adding the chardev, and then adding the device,
674 * we get a device node entry in sysfs under
675 * /sys/bus/gpio/devices/gpiochipN/dev that can be used for
676 * coldplug of device nodes and other udev business.
677 * We can do this only if gpiolib has been initialized.
678 * Otherwise, defer until later.
679 */
680 if (gpiolib_initialized) {
681 ret = gpiochip_setup_dev(gdev);
682 if (ret)
683 goto err_remove_irqchip;
684 }
685 return 0;
686
687err_remove_irqchip:
688 gpiochip_irqchip_remove(gc);
689err_remove_irqchip_mask:
690 gpiochip_irqchip_free_valid_mask(gc);
691err_remove_acpi_chip:
692 acpi_gpiochip_remove(gc);
693err_remove_of_chip:
694 gpiochip_free_hogs(gc);
695 of_gpiochip_remove(gc);
696err_free_gpiochip_mask:
697 gpiochip_remove_pin_ranges(gc);
698 gpiochip_free_valid_mask(gc);
699err_remove_from_list:
700 spin_lock_irqsave(&gpio_lock, flags);
701 list_del(&gdev->list);
702 spin_unlock_irqrestore(&gpio_lock, flags);
703err_free_label:
704 kfree_const(gdev->label);
705err_free_descs:
706 kfree(gdev->descs);
707err_free_ida:
708 ida_simple_remove(&gpio_ida, gdev->id);
709err_free_gdev:
710 /* failures here can mean systems won't boot... */
711 pr_err("%s: GPIOs %d..%d (%s) failed to register, %d\n", __func__,
712 gdev->base, gdev->base + gdev->ngpio - 1,
713 gc->label ? : "generic", ret);
714 kfree(gdev);
715 return ret;
716}
717EXPORT_SYMBOL_GPL(gpiochip_add_data_with_key);
718
719/**
720 * gpiochip_get_data() - get per-subdriver data for the chip
721 * @gc: GPIO chip
722 *
723 * Returns:
724 * The per-subdriver data for the chip.
725 */
726void *gpiochip_get_data(struct gpio_chip *gc)
727{
728 return gc->gpiodev->data;
729}
730EXPORT_SYMBOL_GPL(gpiochip_get_data);
731
732/**
733 * gpiochip_remove() - unregister a gpio_chip
734 * @gc: the chip to unregister
735 *
736 * A gpio_chip with any GPIOs still requested may not be removed.
737 */
738void gpiochip_remove(struct gpio_chip *gc)
739{
740 struct gpio_device *gdev = gc->gpiodev;
741 unsigned long flags;
742 unsigned int i;
743
744 /* FIXME: should the legacy sysfs handling be moved to gpio_device? */
745 gpiochip_sysfs_unregister(gdev);
746 gpiochip_free_hogs(gc);
747 /* Numb the device, cancelling all outstanding operations */
748 gdev->chip = NULL;
749 gpiochip_irqchip_remove(gc);
750 acpi_gpiochip_remove(gc);
751 of_gpiochip_remove(gc);
752 gpiochip_remove_pin_ranges(gc);
753 gpiochip_free_valid_mask(gc);
754 /*
755 * We accept no more calls into the driver from this point, so
756 * NULL the driver data pointer
757 */
758 gdev->data = NULL;
759
760 spin_lock_irqsave(&gpio_lock, flags);
761 for (i = 0; i < gdev->ngpio; i++) {
762 if (gpiochip_is_requested(gc, i))
763 break;
764 }
765 spin_unlock_irqrestore(&gpio_lock, flags);
766
767 if (i != gdev->ngpio)
768 dev_crit(&gdev->dev,
769 "REMOVING GPIOCHIP WITH GPIOS STILL REQUESTED\n");
770
771 /*
772 * The gpiochip side puts its use of the device to rest here:
773 * if there are no userspace clients, the chardev and device will
774 * be removed, else it will be dangling until the last user is
775 * gone.
776 */
777 gpiolib_cdev_unregister(gdev);
778 put_device(&gdev->dev);
779}
780EXPORT_SYMBOL_GPL(gpiochip_remove);
781
782/**
783 * gpiochip_find() - iterator for locating a specific gpio_chip
784 * @data: data to pass to match function
785 * @match: Callback function to check gpio_chip
786 *
787 * Similar to bus_find_device. It returns a reference to a gpio_chip as
788 * determined by a user supplied @match callback. The callback should return
789 * 0 if the device doesn't match and non-zero if it does. If the callback is
790 * non-zero, this function will return to the caller and not iterate over any
791 * more gpio_chips.
792 */
793struct gpio_chip *gpiochip_find(void *data,
794 int (*match)(struct gpio_chip *gc,
795 void *data))
796{
797 struct gpio_device *gdev;
798 struct gpio_chip *gc = NULL;
799 unsigned long flags;
800
801 spin_lock_irqsave(&gpio_lock, flags);
802 list_for_each_entry(gdev, &gpio_devices, list)
803 if (gdev->chip && match(gdev->chip, data)) {
804 gc = gdev->chip;
805 break;
806 }
807
808 spin_unlock_irqrestore(&gpio_lock, flags);
809
810 return gc;
811}
812EXPORT_SYMBOL_GPL(gpiochip_find);
813
814static int gpiochip_match_name(struct gpio_chip *gc, void *data)
815{
816 const char *name = data;
817
818 return !strcmp(gc->label, name);
819}
820
821static struct gpio_chip *find_chip_by_name(const char *name)
822{
823 return gpiochip_find((void *)name, gpiochip_match_name);
824}
825
826#ifdef CONFIG_GPIOLIB_IRQCHIP
827
828/*
829 * The following is irqchip helper code for gpiochips.
830 */
831
832static int gpiochip_irqchip_init_hw(struct gpio_chip *gc)
833{
834 struct gpio_irq_chip *girq = &gc->irq;
835
836 if (!girq->init_hw)
837 return 0;
838
839 return girq->init_hw(gc);
840}
841
842static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gc)
843{
844 struct gpio_irq_chip *girq = &gc->irq;
845
846 if (!girq->init_valid_mask)
847 return 0;
848
849 girq->valid_mask = gpiochip_allocate_mask(gc);
850 if (!girq->valid_mask)
851 return -ENOMEM;
852
853 girq->init_valid_mask(gc, girq->valid_mask, gc->ngpio);
854
855 return 0;
856}
857
858static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gc)
859{
860 bitmap_free(gc->irq.valid_mask);
861 gc->irq.valid_mask = NULL;
862}
863
864bool gpiochip_irqchip_irq_valid(const struct gpio_chip *gc,
865 unsigned int offset)
866{
867 if (!gpiochip_line_is_valid(gc, offset))
868 return false;
869 /* No mask means all valid */
870 if (likely(!gc->irq.valid_mask))
871 return true;
872 return test_bit(offset, gc->irq.valid_mask);
873}
874EXPORT_SYMBOL_GPL(gpiochip_irqchip_irq_valid);
875
876/**
877 * gpiochip_set_cascaded_irqchip() - connects a cascaded irqchip to a gpiochip
878 * @gc: the gpiochip to set the irqchip chain to
879 * @parent_irq: the irq number corresponding to the parent IRQ for this
880 * cascaded irqchip
881 * @parent_handler: the parent interrupt handler for the accumulated IRQ
882 * coming out of the gpiochip. If the interrupt is nested rather than
883 * cascaded, pass NULL in this handler argument
884 */
885static void gpiochip_set_cascaded_irqchip(struct gpio_chip *gc,
886 unsigned int parent_irq,
887 irq_flow_handler_t parent_handler)
888{
889 struct gpio_irq_chip *girq = &gc->irq;
890 struct device *dev = &gc->gpiodev->dev;
891
892 if (!girq->domain) {
893 chip_err(gc, "called %s before setting up irqchip\n",
894 __func__);
895 return;
896 }
897
898 if (parent_handler) {
899 if (gc->can_sleep) {
900 chip_err(gc,
901 "you cannot have chained interrupts on a chip that may sleep\n");
902 return;
903 }
904 girq->parents = devm_kcalloc(dev, 1,
905 sizeof(*girq->parents),
906 GFP_KERNEL);
907 if (!girq->parents) {
908 chip_err(gc, "out of memory allocating parent IRQ\n");
909 return;
910 }
911 girq->parents[0] = parent_irq;
912 girq->num_parents = 1;
913 /*
914 * The parent irqchip is already using the chip_data for this
915 * irqchip, so our callbacks simply use the handler_data.
916 */
917 irq_set_chained_handler_and_data(parent_irq, parent_handler,
918 gc);
919 }
920}
921
922/**
923 * gpiochip_set_nested_irqchip() - connects a nested irqchip to a gpiochip
924 * @gc: the gpiochip to set the irqchip nested handler to
925 * @irqchip: the irqchip to nest to the gpiochip
926 * @parent_irq: the irq number corresponding to the parent IRQ for this
927 * nested irqchip
928 */
929void gpiochip_set_nested_irqchip(struct gpio_chip *gc,
930 struct irq_chip *irqchip,
931 unsigned int parent_irq)
932{
933 gpiochip_set_cascaded_irqchip(gc, parent_irq, NULL);
934}
935EXPORT_SYMBOL_GPL(gpiochip_set_nested_irqchip);
936
937#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
938
939/**
940 * gpiochip_set_hierarchical_irqchip() - connects a hierarchical irqchip
941 * to a gpiochip
942 * @gc: the gpiochip to set the irqchip hierarchical handler to
943 * @irqchip: the irqchip to handle this level of the hierarchy, the interrupt
944 * will then percolate up to the parent
945 */
946static void gpiochip_set_hierarchical_irqchip(struct gpio_chip *gc,
947 struct irq_chip *irqchip)
948{
949 /* DT will deal with mapping each IRQ as we go along */
950 if (is_of_node(gc->irq.fwnode))
951 return;
952
953 /*
954 * This is for legacy and boardfile "irqchip" fwnodes: allocate
955 * irqs upfront instead of dynamically since we don't have the
956 * dynamic type of allocation that hardware description languages
957 * provide. Once all GPIO drivers using board files are gone from
958 * the kernel we can delete this code, but for a transitional period
959 * it is necessary to keep this around.
960 */
961 if (is_fwnode_irqchip(gc->irq.fwnode)) {
962 int i;
963 int ret;
964
965 for (i = 0; i < gc->ngpio; i++) {
966 struct irq_fwspec fwspec;
967 unsigned int parent_hwirq;
968 unsigned int parent_type;
969 struct gpio_irq_chip *girq = &gc->irq;
970
971 /*
972 * We call the child to parent translation function
973 * only to check if the child IRQ is valid or not.
974 * Just pick the rising edge type here as that is what
975 * we likely need to support.
976 */
977 ret = girq->child_to_parent_hwirq(gc, i,
978 IRQ_TYPE_EDGE_RISING,
979 &parent_hwirq,
980 &parent_type);
981 if (ret) {
982 chip_err(gc, "skip set-up on hwirq %d\n",
983 i);
984 continue;
985 }
986
987 fwspec.fwnode = gc->irq.fwnode;
988 /* This is the hwirq for the GPIO line side of things */
989 fwspec.param[0] = girq->child_offset_to_irq(gc, i);
990 /* Just pick something */
991 fwspec.param[1] = IRQ_TYPE_EDGE_RISING;
992 fwspec.param_count = 2;
993 ret = __irq_domain_alloc_irqs(gc->irq.domain,
994 /* just pick something */
995 -1,
996 1,
997 NUMA_NO_NODE,
998 &fwspec,
999 false,
1000 NULL);
1001 if (ret < 0) {
1002 chip_err(gc,
1003 "can not allocate irq for GPIO line %d parent hwirq %d in hierarchy domain: %d\n",
1004 i, parent_hwirq,
1005 ret);
1006 }
1007 }
1008 }
1009
1010 chip_err(gc, "%s unknown fwnode type proceed anyway\n", __func__);
1011
1012 return;
1013}
1014
1015static int gpiochip_hierarchy_irq_domain_translate(struct irq_domain *d,
1016 struct irq_fwspec *fwspec,
1017 unsigned long *hwirq,
1018 unsigned int *type)
1019{
1020 /* We support standard DT translation */
1021 if (is_of_node(fwspec->fwnode) && fwspec->param_count == 2) {
1022 return irq_domain_translate_twocell(d, fwspec, hwirq, type);
1023 }
1024
1025 /* This is for board files and others not using DT */
1026 if (is_fwnode_irqchip(fwspec->fwnode)) {
1027 int ret;
1028
1029 ret = irq_domain_translate_twocell(d, fwspec, hwirq, type);
1030 if (ret)
1031 return ret;
1032 WARN_ON(*type == IRQ_TYPE_NONE);
1033 return 0;
1034 }
1035 return -EINVAL;
1036}
1037
1038static int gpiochip_hierarchy_irq_domain_alloc(struct irq_domain *d,
1039 unsigned int irq,
1040 unsigned int nr_irqs,
1041 void *data)
1042{
1043 struct gpio_chip *gc = d->host_data;
1044 irq_hw_number_t hwirq;
1045 unsigned int type = IRQ_TYPE_NONE;
1046 struct irq_fwspec *fwspec = data;
1047 void *parent_arg;
1048 unsigned int parent_hwirq;
1049 unsigned int parent_type;
1050 struct gpio_irq_chip *girq = &gc->irq;
1051 int ret;
1052
1053 /*
1054 * The nr_irqs parameter is always one except for PCI multi-MSI
1055 * so this should not happen.
1056 */
1057 WARN_ON(nr_irqs != 1);
1058
1059 ret = gc->irq.child_irq_domain_ops.translate(d, fwspec, &hwirq, &type);
1060 if (ret)
1061 return ret;
1062
1063 chip_dbg(gc, "allocate IRQ %d, hwirq %lu\n", irq, hwirq);
1064
1065 ret = girq->child_to_parent_hwirq(gc, hwirq, type,
1066 &parent_hwirq, &parent_type);
1067 if (ret) {
1068 chip_err(gc, "can't look up hwirq %lu\n", hwirq);
1069 return ret;
1070 }
1071 chip_dbg(gc, "found parent hwirq %u\n", parent_hwirq);
1072
1073 /*
1074 * We set handle_bad_irq because the .set_type() should
1075 * always be invoked and set the right type of handler.
1076 */
1077 irq_domain_set_info(d,
1078 irq,
1079 hwirq,
1080 gc->irq.chip,
1081 gc,
1082 girq->handler,
1083 NULL, NULL);
1084 irq_set_probe(irq);
1085
1086 /* This parent only handles asserted level IRQs */
1087 parent_arg = girq->populate_parent_alloc_arg(gc, parent_hwirq, parent_type);
1088 if (!parent_arg)
1089 return -ENOMEM;
1090
1091 chip_dbg(gc, "alloc_irqs_parent for %d parent hwirq %d\n",
1092 irq, parent_hwirq);
1093 irq_set_lockdep_class(irq, gc->irq.lock_key, gc->irq.request_key);
1094 ret = irq_domain_alloc_irqs_parent(d, irq, 1, parent_arg);
1095 /*
1096 * If the parent irqdomain is msi, the interrupts have already
1097 * been allocated, so the EEXIST is good.
1098 */
1099 if (irq_domain_is_msi(d->parent) && (ret == -EEXIST))
1100 ret = 0;
1101 if (ret)
1102 chip_err(gc,
1103 "failed to allocate parent hwirq %d for hwirq %lu\n",
1104 parent_hwirq, hwirq);
1105
1106 kfree(parent_arg);
1107 return ret;
1108}
1109
1110static unsigned int gpiochip_child_offset_to_irq_noop(struct gpio_chip *gc,
1111 unsigned int offset)
1112{
1113 return offset;
1114}
1115
1116static void gpiochip_hierarchy_setup_domain_ops(struct irq_domain_ops *ops)
1117{
1118 ops->activate = gpiochip_irq_domain_activate;
1119 ops->deactivate = gpiochip_irq_domain_deactivate;
1120 ops->alloc = gpiochip_hierarchy_irq_domain_alloc;
1121 ops->free = irq_domain_free_irqs_common;
1122
1123 /*
1124 * We only allow overriding the translate() function for
1125 * hierarchical chips, and this should only be done if the user
1126 * really need something other than 1:1 translation.
1127 */
1128 if (!ops->translate)
1129 ops->translate = gpiochip_hierarchy_irq_domain_translate;
1130}
1131
1132static int gpiochip_hierarchy_add_domain(struct gpio_chip *gc)
1133{
1134 if (!gc->irq.child_to_parent_hwirq ||
1135 !gc->irq.fwnode) {
1136 chip_err(gc, "missing irqdomain vital data\n");
1137 return -EINVAL;
1138 }
1139
1140 if (!gc->irq.child_offset_to_irq)
1141 gc->irq.child_offset_to_irq = gpiochip_child_offset_to_irq_noop;
1142
1143 if (!gc->irq.populate_parent_alloc_arg)
1144 gc->irq.populate_parent_alloc_arg =
1145 gpiochip_populate_parent_fwspec_twocell;
1146
1147 gpiochip_hierarchy_setup_domain_ops(&gc->irq.child_irq_domain_ops);
1148
1149 gc->irq.domain = irq_domain_create_hierarchy(
1150 gc->irq.parent_domain,
1151 0,
1152 gc->ngpio,
1153 gc->irq.fwnode,
1154 &gc->irq.child_irq_domain_ops,
1155 gc);
1156
1157 if (!gc->irq.domain)
1158 return -ENOMEM;
1159
1160 gpiochip_set_hierarchical_irqchip(gc, gc->irq.chip);
1161
1162 return 0;
1163}
1164
1165static bool gpiochip_hierarchy_is_hierarchical(struct gpio_chip *gc)
1166{
1167 return !!gc->irq.parent_domain;
1168}
1169
1170void *gpiochip_populate_parent_fwspec_twocell(struct gpio_chip *gc,
1171 unsigned int parent_hwirq,
1172 unsigned int parent_type)
1173{
1174 struct irq_fwspec *fwspec;
1175
1176 fwspec = kmalloc(sizeof(*fwspec), GFP_KERNEL);
1177 if (!fwspec)
1178 return NULL;
1179
1180 fwspec->fwnode = gc->irq.parent_domain->fwnode;
1181 fwspec->param_count = 2;
1182 fwspec->param[0] = parent_hwirq;
1183 fwspec->param[1] = parent_type;
1184
1185 return fwspec;
1186}
1187EXPORT_SYMBOL_GPL(gpiochip_populate_parent_fwspec_twocell);
1188
1189void *gpiochip_populate_parent_fwspec_fourcell(struct gpio_chip *gc,
1190 unsigned int parent_hwirq,
1191 unsigned int parent_type)
1192{
1193 struct irq_fwspec *fwspec;
1194
1195 fwspec = kmalloc(sizeof(*fwspec), GFP_KERNEL);
1196 if (!fwspec)
1197 return NULL;
1198
1199 fwspec->fwnode = gc->irq.parent_domain->fwnode;
1200 fwspec->param_count = 4;
1201 fwspec->param[0] = 0;
1202 fwspec->param[1] = parent_hwirq;
1203 fwspec->param[2] = 0;
1204 fwspec->param[3] = parent_type;
1205
1206 return fwspec;
1207}
1208EXPORT_SYMBOL_GPL(gpiochip_populate_parent_fwspec_fourcell);
1209
1210#else
1211
1212static int gpiochip_hierarchy_add_domain(struct gpio_chip *gc)
1213{
1214 return -EINVAL;
1215}
1216
1217static bool gpiochip_hierarchy_is_hierarchical(struct gpio_chip *gc)
1218{
1219 return false;
1220}
1221
1222#endif /* CONFIG_IRQ_DOMAIN_HIERARCHY */
1223
1224/**
1225 * gpiochip_irq_map() - maps an IRQ into a GPIO irqchip
1226 * @d: the irqdomain used by this irqchip
1227 * @irq: the global irq number used by this GPIO irqchip irq
1228 * @hwirq: the local IRQ/GPIO line offset on this gpiochip
1229 *
1230 * This function will set up the mapping for a certain IRQ line on a
1231 * gpiochip by assigning the gpiochip as chip data, and using the irqchip
1232 * stored inside the gpiochip.
1233 */
1234int gpiochip_irq_map(struct irq_domain *d, unsigned int irq,
1235 irq_hw_number_t hwirq)
1236{
1237 struct gpio_chip *gc = d->host_data;
1238 int ret = 0;
1239
1240 if (!gpiochip_irqchip_irq_valid(gc, hwirq))
1241 return -ENXIO;
1242
1243 irq_set_chip_data(irq, gc);
1244 /*
1245 * This lock class tells lockdep that GPIO irqs are in a different
1246 * category than their parents, so it won't report false recursion.
1247 */
1248 irq_set_lockdep_class(irq, gc->irq.lock_key, gc->irq.request_key);
1249 irq_set_chip_and_handler(irq, gc->irq.chip, gc->irq.handler);
1250 /* Chips that use nested thread handlers have them marked */
1251 if (gc->irq.threaded)
1252 irq_set_nested_thread(irq, 1);
1253 irq_set_noprobe(irq);
1254
1255 if (gc->irq.num_parents == 1)
1256 ret = irq_set_parent(irq, gc->irq.parents[0]);
1257 else if (gc->irq.map)
1258 ret = irq_set_parent(irq, gc->irq.map[hwirq]);
1259
1260 if (ret < 0)
1261 return ret;
1262
1263 /*
1264 * No set-up of the hardware will happen if IRQ_TYPE_NONE
1265 * is passed as default type.
1266 */
1267 if (gc->irq.default_type != IRQ_TYPE_NONE)
1268 irq_set_irq_type(irq, gc->irq.default_type);
1269
1270 return 0;
1271}
1272EXPORT_SYMBOL_GPL(gpiochip_irq_map);
1273
1274void gpiochip_irq_unmap(struct irq_domain *d, unsigned int irq)
1275{
1276 struct gpio_chip *gc = d->host_data;
1277
1278 if (gc->irq.threaded)
1279 irq_set_nested_thread(irq, 0);
1280 irq_set_chip_and_handler(irq, NULL, NULL);
1281 irq_set_chip_data(irq, NULL);
1282}
1283EXPORT_SYMBOL_GPL(gpiochip_irq_unmap);
1284
1285static const struct irq_domain_ops gpiochip_domain_ops = {
1286 .map = gpiochip_irq_map,
1287 .unmap = gpiochip_irq_unmap,
1288 /* Virtually all GPIO irqchips are twocell:ed */
1289 .xlate = irq_domain_xlate_twocell,
1290};
1291
1292/*
1293 * TODO: move these activate/deactivate in under the hierarchicial
1294 * irqchip implementation as static once SPMI and SSBI (all external
1295 * users) are phased over.
1296 */
1297/**
1298 * gpiochip_irq_domain_activate() - Lock a GPIO to be used as an IRQ
1299 * @domain: The IRQ domain used by this IRQ chip
1300 * @data: Outermost irq_data associated with the IRQ
1301 * @reserve: If set, only reserve an interrupt vector instead of assigning one
1302 *
1303 * This function is a wrapper that calls gpiochip_lock_as_irq() and is to be
1304 * used as the activate function for the &struct irq_domain_ops. The host_data
1305 * for the IRQ domain must be the &struct gpio_chip.
1306 */
1307int gpiochip_irq_domain_activate(struct irq_domain *domain,
1308 struct irq_data *data, bool reserve)
1309{
1310 struct gpio_chip *gc = domain->host_data;
1311
1312 return gpiochip_lock_as_irq(gc, data->hwirq);
1313}
1314EXPORT_SYMBOL_GPL(gpiochip_irq_domain_activate);
1315
1316/**
1317 * gpiochip_irq_domain_deactivate() - Unlock a GPIO used as an IRQ
1318 * @domain: The IRQ domain used by this IRQ chip
1319 * @data: Outermost irq_data associated with the IRQ
1320 *
1321 * This function is a wrapper that will call gpiochip_unlock_as_irq() and is to
1322 * be used as the deactivate function for the &struct irq_domain_ops. The
1323 * host_data for the IRQ domain must be the &struct gpio_chip.
1324 */
1325void gpiochip_irq_domain_deactivate(struct irq_domain *domain,
1326 struct irq_data *data)
1327{
1328 struct gpio_chip *gc = domain->host_data;
1329
1330 return gpiochip_unlock_as_irq(gc, data->hwirq);
1331}
1332EXPORT_SYMBOL_GPL(gpiochip_irq_domain_deactivate);
1333
1334static int gpiochip_to_irq(struct gpio_chip *gc, unsigned offset)
1335{
1336 struct irq_domain *domain = gc->irq.domain;
1337
1338 if (!gpiochip_irqchip_irq_valid(gc, offset))
1339 return -ENXIO;
1340
1341#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
1342 if (irq_domain_is_hierarchy(domain)) {
1343 struct irq_fwspec spec;
1344
1345 spec.fwnode = domain->fwnode;
1346 spec.param_count = 2;
1347 spec.param[0] = gc->irq.child_offset_to_irq(gc, offset);
1348 spec.param[1] = IRQ_TYPE_NONE;
1349
1350 return irq_create_fwspec_mapping(&spec);
1351 }
1352#endif
1353
1354 return irq_create_mapping(domain, offset);
1355}
1356
1357static int gpiochip_irq_reqres(struct irq_data *d)
1358{
1359 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1360
1361 return gpiochip_reqres_irq(gc, d->hwirq);
1362}
1363
1364static void gpiochip_irq_relres(struct irq_data *d)
1365{
1366 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1367
1368 gpiochip_relres_irq(gc, d->hwirq);
1369}
1370
1371static void gpiochip_irq_mask(struct irq_data *d)
1372{
1373 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1374
1375 if (gc->irq.irq_mask)
1376 gc->irq.irq_mask(d);
1377 gpiochip_disable_irq(gc, d->hwirq);
1378}
1379
1380static void gpiochip_irq_unmask(struct irq_data *d)
1381{
1382 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1383
1384 gpiochip_enable_irq(gc, d->hwirq);
1385 if (gc->irq.irq_unmask)
1386 gc->irq.irq_unmask(d);
1387}
1388
1389static void gpiochip_irq_enable(struct irq_data *d)
1390{
1391 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1392
1393 gpiochip_enable_irq(gc, d->hwirq);
1394 gc->irq.irq_enable(d);
1395}
1396
1397static void gpiochip_irq_disable(struct irq_data *d)
1398{
1399 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1400
1401 gc->irq.irq_disable(d);
1402 gpiochip_disable_irq(gc, d->hwirq);
1403}
1404
1405static void gpiochip_set_irq_hooks(struct gpio_chip *gc)
1406{
1407 struct irq_chip *irqchip = gc->irq.chip;
1408
1409 if (!irqchip->irq_request_resources &&
1410 !irqchip->irq_release_resources) {
1411 irqchip->irq_request_resources = gpiochip_irq_reqres;
1412 irqchip->irq_release_resources = gpiochip_irq_relres;
1413 }
1414 if (WARN_ON(gc->irq.irq_enable))
1415 return;
1416 /* Check if the irqchip already has this hook... */
1417 if (irqchip->irq_enable == gpiochip_irq_enable) {
1418 /*
1419 * ...and if so, give a gentle warning that this is bad
1420 * practice.
1421 */
1422 chip_info(gc,
1423 "detected irqchip that is shared with multiple gpiochips: please fix the driver.\n");
1424 return;
1425 }
1426
1427 if (irqchip->irq_disable) {
1428 gc->irq.irq_disable = irqchip->irq_disable;
1429 irqchip->irq_disable = gpiochip_irq_disable;
1430 } else {
1431 gc->irq.irq_mask = irqchip->irq_mask;
1432 irqchip->irq_mask = gpiochip_irq_mask;
1433 }
1434
1435 if (irqchip->irq_enable) {
1436 gc->irq.irq_enable = irqchip->irq_enable;
1437 irqchip->irq_enable = gpiochip_irq_enable;
1438 } else {
1439 gc->irq.irq_unmask = irqchip->irq_unmask;
1440 irqchip->irq_unmask = gpiochip_irq_unmask;
1441 }
1442}
1443
1444/**
1445 * gpiochip_add_irqchip() - adds an IRQ chip to a GPIO chip
1446 * @gc: the GPIO chip to add the IRQ chip to
1447 * @lock_key: lockdep class for IRQ lock
1448 * @request_key: lockdep class for IRQ request
1449 */
1450static int gpiochip_add_irqchip(struct gpio_chip *gc,
1451 struct lock_class_key *lock_key,
1452 struct lock_class_key *request_key)
1453{
1454 struct irq_chip *irqchip = gc->irq.chip;
1455 const struct irq_domain_ops *ops = NULL;
1456 struct device_node *np;
1457 unsigned int type;
1458 unsigned int i;
1459
1460 if (!irqchip)
1461 return 0;
1462
1463 if (gc->irq.parent_handler && gc->can_sleep) {
1464 chip_err(gc, "you cannot have chained interrupts on a chip that may sleep\n");
1465 return -EINVAL;
1466 }
1467
1468 np = gc->gpiodev->dev.of_node;
1469 type = gc->irq.default_type;
1470
1471 /*
1472 * Specifying a default trigger is a terrible idea if DT or ACPI is
1473 * used to configure the interrupts, as you may end up with
1474 * conflicting triggers. Tell the user, and reset to NONE.
1475 */
1476 if (WARN(np && type != IRQ_TYPE_NONE,
1477 "%s: Ignoring %u default trigger\n", np->full_name, type))
1478 type = IRQ_TYPE_NONE;
1479
1480 if (has_acpi_companion(gc->parent) && type != IRQ_TYPE_NONE) {
1481 acpi_handle_warn(ACPI_HANDLE(gc->parent),
1482 "Ignoring %u default trigger\n", type);
1483 type = IRQ_TYPE_NONE;
1484 }
1485
1486 gc->to_irq = gpiochip_to_irq;
1487 gc->irq.default_type = type;
1488 gc->irq.lock_key = lock_key;
1489 gc->irq.request_key = request_key;
1490
1491 /* If a parent irqdomain is provided, let's build a hierarchy */
1492 if (gpiochip_hierarchy_is_hierarchical(gc)) {
1493 int ret = gpiochip_hierarchy_add_domain(gc);
1494 if (ret)
1495 return ret;
1496 } else {
1497 /* Some drivers provide custom irqdomain ops */
1498 if (gc->irq.domain_ops)
1499 ops = gc->irq.domain_ops;
1500
1501 if (!ops)
1502 ops = &gpiochip_domain_ops;
1503 gc->irq.domain = irq_domain_add_simple(np,
1504 gc->ngpio,
1505 gc->irq.first,
1506 ops, gc);
1507 if (!gc->irq.domain)
1508 return -EINVAL;
1509 }
1510
1511 if (gc->irq.parent_handler) {
1512 void *data = gc->irq.parent_handler_data ?: gc;
1513
1514 for (i = 0; i < gc->irq.num_parents; i++) {
1515 /*
1516 * The parent IRQ chip is already using the chip_data
1517 * for this IRQ chip, so our callbacks simply use the
1518 * handler_data.
1519 */
1520 irq_set_chained_handler_and_data(gc->irq.parents[i],
1521 gc->irq.parent_handler,
1522 data);
1523 }
1524 }
1525
1526 gpiochip_set_irq_hooks(gc);
1527
1528 acpi_gpiochip_request_interrupts(gc);
1529
1530 return 0;
1531}
1532
1533/**
1534 * gpiochip_irqchip_remove() - removes an irqchip added to a gpiochip
1535 * @gc: the gpiochip to remove the irqchip from
1536 *
1537 * This is called only from gpiochip_remove()
1538 */
1539static void gpiochip_irqchip_remove(struct gpio_chip *gc)
1540{
1541 struct irq_chip *irqchip = gc->irq.chip;
1542 unsigned int offset;
1543
1544 acpi_gpiochip_free_interrupts(gc);
1545
1546 if (irqchip && gc->irq.parent_handler) {
1547 struct gpio_irq_chip *irq = &gc->irq;
1548 unsigned int i;
1549
1550 for (i = 0; i < irq->num_parents; i++)
1551 irq_set_chained_handler_and_data(irq->parents[i],
1552 NULL, NULL);
1553 }
1554
1555 /* Remove all IRQ mappings and delete the domain */
1556 if (gc->irq.domain) {
1557 unsigned int irq;
1558
1559 for (offset = 0; offset < gc->ngpio; offset++) {
1560 if (!gpiochip_irqchip_irq_valid(gc, offset))
1561 continue;
1562
1563 irq = irq_find_mapping(gc->irq.domain, offset);
1564 irq_dispose_mapping(irq);
1565 }
1566
1567 irq_domain_remove(gc->irq.domain);
1568 }
1569
1570 if (irqchip) {
1571 if (irqchip->irq_request_resources == gpiochip_irq_reqres) {
1572 irqchip->irq_request_resources = NULL;
1573 irqchip->irq_release_resources = NULL;
1574 }
1575 if (irqchip->irq_enable == gpiochip_irq_enable) {
1576 irqchip->irq_enable = gc->irq.irq_enable;
1577 irqchip->irq_disable = gc->irq.irq_disable;
1578 }
1579 }
1580 gc->irq.irq_enable = NULL;
1581 gc->irq.irq_disable = NULL;
1582 gc->irq.chip = NULL;
1583
1584 gpiochip_irqchip_free_valid_mask(gc);
1585}
1586
1587/**
1588 * gpiochip_irqchip_add_key() - adds an irqchip to a gpiochip
1589 * @gc: the gpiochip to add the irqchip to
1590 * @irqchip: the irqchip to add to the gpiochip
1591 * @first_irq: if not dynamically assigned, the base (first) IRQ to
1592 * allocate gpiochip irqs from
1593 * @handler: the irq handler to use (often a predefined irq core function)
1594 * @type: the default type for IRQs on this irqchip, pass IRQ_TYPE_NONE
1595 * to have the core avoid setting up any default type in the hardware.
1596 * @threaded: whether this irqchip uses a nested thread handler
1597 * @lock_key: lockdep class for IRQ lock
1598 * @request_key: lockdep class for IRQ request
1599 *
1600 * This function closely associates a certain irqchip with a certain
1601 * gpiochip, providing an irq domain to translate the local IRQs to
1602 * global irqs in the gpiolib core, and making sure that the gpiochip
1603 * is passed as chip data to all related functions. Driver callbacks
1604 * need to use gpiochip_get_data() to get their local state containers back
1605 * from the gpiochip passed as chip data. An irqdomain will be stored
1606 * in the gpiochip that shall be used by the driver to handle IRQ number
1607 * translation. The gpiochip will need to be initialized and registered
1608 * before calling this function.
1609 *
1610 * This function will handle two cell:ed simple IRQs and assumes all
1611 * the pins on the gpiochip can generate a unique IRQ. Everything else
1612 * need to be open coded.
1613 */
1614int gpiochip_irqchip_add_key(struct gpio_chip *gc,
1615 struct irq_chip *irqchip,
1616 unsigned int first_irq,
1617 irq_flow_handler_t handler,
1618 unsigned int type,
1619 bool threaded,
1620 struct lock_class_key *lock_key,
1621 struct lock_class_key *request_key)
1622{
1623 struct device_node *of_node;
1624
1625 if (!gc || !irqchip)
1626 return -EINVAL;
1627
1628 if (!gc->parent) {
1629 chip_err(gc, "missing gpiochip .dev parent pointer\n");
1630 return -EINVAL;
1631 }
1632 gc->irq.threaded = threaded;
1633 of_node = gc->parent->of_node;
1634#ifdef CONFIG_OF_GPIO
1635 /*
1636 * If the gpiochip has an assigned OF node this takes precedence
1637 * FIXME: get rid of this and use gc->parent->of_node
1638 * everywhere
1639 */
1640 if (gc->of_node)
1641 of_node = gc->of_node;
1642#endif
1643 /*
1644 * Specifying a default trigger is a terrible idea if DT or ACPI is
1645 * used to configure the interrupts, as you may end-up with
1646 * conflicting triggers. Tell the user, and reset to NONE.
1647 */
1648 if (WARN(of_node && type != IRQ_TYPE_NONE,
1649 "%pOF: Ignoring %d default trigger\n", of_node, type))
1650 type = IRQ_TYPE_NONE;
1651 if (has_acpi_companion(gc->parent) && type != IRQ_TYPE_NONE) {
1652 acpi_handle_warn(ACPI_HANDLE(gc->parent),
1653 "Ignoring %d default trigger\n", type);
1654 type = IRQ_TYPE_NONE;
1655 }
1656
1657 gc->irq.chip = irqchip;
1658 gc->irq.handler = handler;
1659 gc->irq.default_type = type;
1660 gc->to_irq = gpiochip_to_irq;
1661 gc->irq.lock_key = lock_key;
1662 gc->irq.request_key = request_key;
1663 gc->irq.domain = irq_domain_add_simple(of_node,
1664 gc->ngpio, first_irq,
1665 &gpiochip_domain_ops, gc);
1666 if (!gc->irq.domain) {
1667 gc->irq.chip = NULL;
1668 return -EINVAL;
1669 }
1670
1671 gpiochip_set_irq_hooks(gc);
1672
1673 acpi_gpiochip_request_interrupts(gc);
1674
1675 return 0;
1676}
1677EXPORT_SYMBOL_GPL(gpiochip_irqchip_add_key);
1678
1679/**
1680 * gpiochip_irqchip_add_domain() - adds an irqdomain to a gpiochip
1681 * @gc: the gpiochip to add the irqchip to
1682 * @domain: the irqdomain to add to the gpiochip
1683 *
1684 * This function adds an IRQ domain to the gpiochip.
1685 */
1686int gpiochip_irqchip_add_domain(struct gpio_chip *gc,
1687 struct irq_domain *domain)
1688{
1689 if (!domain)
1690 return -EINVAL;
1691
1692 gc->to_irq = gpiochip_to_irq;
1693 gc->irq.domain = domain;
1694
1695 return 0;
1696}
1697EXPORT_SYMBOL_GPL(gpiochip_irqchip_add_domain);
1698
1699#else /* CONFIG_GPIOLIB_IRQCHIP */
1700
1701static inline int gpiochip_add_irqchip(struct gpio_chip *gc,
1702 struct lock_class_key *lock_key,
1703 struct lock_class_key *request_key)
1704{
1705 return 0;
1706}
1707static void gpiochip_irqchip_remove(struct gpio_chip *gc) {}
1708
1709static inline int gpiochip_irqchip_init_hw(struct gpio_chip *gc)
1710{
1711 return 0;
1712}
1713
1714static inline int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gc)
1715{
1716 return 0;
1717}
1718static inline void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gc)
1719{ }
1720
1721#endif /* CONFIG_GPIOLIB_IRQCHIP */
1722
1723/**
1724 * gpiochip_generic_request() - request the gpio function for a pin
1725 * @gc: the gpiochip owning the GPIO
1726 * @offset: the offset of the GPIO to request for GPIO function
1727 */
1728int gpiochip_generic_request(struct gpio_chip *gc, unsigned offset)
1729{
1730#ifdef CONFIG_PINCTRL
1731 if (list_empty(&gc->gpiodev->pin_ranges))
1732 return 0;
1733#endif
1734
1735 return pinctrl_gpio_request(gc->gpiodev->base + offset);
1736}
1737EXPORT_SYMBOL_GPL(gpiochip_generic_request);
1738
1739/**
1740 * gpiochip_generic_free() - free the gpio function from a pin
1741 * @gc: the gpiochip to request the gpio function for
1742 * @offset: the offset of the GPIO to free from GPIO function
1743 */
1744void gpiochip_generic_free(struct gpio_chip *gc, unsigned offset)
1745{
1746 pinctrl_gpio_free(gc->gpiodev->base + offset);
1747}
1748EXPORT_SYMBOL_GPL(gpiochip_generic_free);
1749
1750/**
1751 * gpiochip_generic_config() - apply configuration for a pin
1752 * @gc: the gpiochip owning the GPIO
1753 * @offset: the offset of the GPIO to apply the configuration
1754 * @config: the configuration to be applied
1755 */
1756int gpiochip_generic_config(struct gpio_chip *gc, unsigned offset,
1757 unsigned long config)
1758{
1759 return pinctrl_gpio_set_config(gc->gpiodev->base + offset, config);
1760}
1761EXPORT_SYMBOL_GPL(gpiochip_generic_config);
1762
1763#ifdef CONFIG_PINCTRL
1764
1765/**
1766 * gpiochip_add_pingroup_range() - add a range for GPIO <-> pin mapping
1767 * @gc: the gpiochip to add the range for
1768 * @pctldev: the pin controller to map to
1769 * @gpio_offset: the start offset in the current gpio_chip number space
1770 * @pin_group: name of the pin group inside the pin controller
1771 *
1772 * Calling this function directly from a DeviceTree-supported
1773 * pinctrl driver is DEPRECATED. Please see Section 2.1 of
1774 * Documentation/devicetree/bindings/gpio/gpio.txt on how to
1775 * bind pinctrl and gpio drivers via the "gpio-ranges" property.
1776 */
1777int gpiochip_add_pingroup_range(struct gpio_chip *gc,
1778 struct pinctrl_dev *pctldev,
1779 unsigned int gpio_offset, const char *pin_group)
1780{
1781 struct gpio_pin_range *pin_range;
1782 struct gpio_device *gdev = gc->gpiodev;
1783 int ret;
1784
1785 pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL);
1786 if (!pin_range) {
1787 chip_err(gc, "failed to allocate pin ranges\n");
1788 return -ENOMEM;
1789 }
1790
1791 /* Use local offset as range ID */
1792 pin_range->range.id = gpio_offset;
1793 pin_range->range.gc = gc;
1794 pin_range->range.name = gc->label;
1795 pin_range->range.base = gdev->base + gpio_offset;
1796 pin_range->pctldev = pctldev;
1797
1798 ret = pinctrl_get_group_pins(pctldev, pin_group,
1799 &pin_range->range.pins,
1800 &pin_range->range.npins);
1801 if (ret < 0) {
1802 kfree(pin_range);
1803 return ret;
1804 }
1805
1806 pinctrl_add_gpio_range(pctldev, &pin_range->range);
1807
1808 chip_dbg(gc, "created GPIO range %d->%d ==> %s PINGRP %s\n",
1809 gpio_offset, gpio_offset + pin_range->range.npins - 1,
1810 pinctrl_dev_get_devname(pctldev), pin_group);
1811
1812 list_add_tail(&pin_range->node, &gdev->pin_ranges);
1813
1814 return 0;
1815}
1816EXPORT_SYMBOL_GPL(gpiochip_add_pingroup_range);
1817
1818/**
1819 * gpiochip_add_pin_range() - add a range for GPIO <-> pin mapping
1820 * @gc: the gpiochip to add the range for
1821 * @pinctl_name: the dev_name() of the pin controller to map to
1822 * @gpio_offset: the start offset in the current gpio_chip number space
1823 * @pin_offset: the start offset in the pin controller number space
1824 * @npins: the number of pins from the offset of each pin space (GPIO and
1825 * pin controller) to accumulate in this range
1826 *
1827 * Returns:
1828 * 0 on success, or a negative error-code on failure.
1829 *
1830 * Calling this function directly from a DeviceTree-supported
1831 * pinctrl driver is DEPRECATED. Please see Section 2.1 of
1832 * Documentation/devicetree/bindings/gpio/gpio.txt on how to
1833 * bind pinctrl and gpio drivers via the "gpio-ranges" property.
1834 */
1835int gpiochip_add_pin_range(struct gpio_chip *gc, const char *pinctl_name,
1836 unsigned int gpio_offset, unsigned int pin_offset,
1837 unsigned int npins)
1838{
1839 struct gpio_pin_range *pin_range;
1840 struct gpio_device *gdev = gc->gpiodev;
1841 int ret;
1842
1843 pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL);
1844 if (!pin_range) {
1845 chip_err(gc, "failed to allocate pin ranges\n");
1846 return -ENOMEM;
1847 }
1848
1849 /* Use local offset as range ID */
1850 pin_range->range.id = gpio_offset;
1851 pin_range->range.gc = gc;
1852 pin_range->range.name = gc->label;
1853 pin_range->range.base = gdev->base + gpio_offset;
1854 pin_range->range.pin_base = pin_offset;
1855 pin_range->range.npins = npins;
1856 pin_range->pctldev = pinctrl_find_and_add_gpio_range(pinctl_name,
1857 &pin_range->range);
1858 if (IS_ERR(pin_range->pctldev)) {
1859 ret = PTR_ERR(pin_range->pctldev);
1860 chip_err(gc, "could not create pin range\n");
1861 kfree(pin_range);
1862 return ret;
1863 }
1864 chip_dbg(gc, "created GPIO range %d->%d ==> %s PIN %d->%d\n",
1865 gpio_offset, gpio_offset + npins - 1,
1866 pinctl_name,
1867 pin_offset, pin_offset + npins - 1);
1868
1869 list_add_tail(&pin_range->node, &gdev->pin_ranges);
1870
1871 return 0;
1872}
1873EXPORT_SYMBOL_GPL(gpiochip_add_pin_range);
1874
1875/**
1876 * gpiochip_remove_pin_ranges() - remove all the GPIO <-> pin mappings
1877 * @gc: the chip to remove all the mappings for
1878 */
1879void gpiochip_remove_pin_ranges(struct gpio_chip *gc)
1880{
1881 struct gpio_pin_range *pin_range, *tmp;
1882 struct gpio_device *gdev = gc->gpiodev;
1883
1884 list_for_each_entry_safe(pin_range, tmp, &gdev->pin_ranges, node) {
1885 list_del(&pin_range->node);
1886 pinctrl_remove_gpio_range(pin_range->pctldev,
1887 &pin_range->range);
1888 kfree(pin_range);
1889 }
1890}
1891EXPORT_SYMBOL_GPL(gpiochip_remove_pin_ranges);
1892
1893#endif /* CONFIG_PINCTRL */
1894
1895/* These "optional" allocation calls help prevent drivers from stomping
1896 * on each other, and help provide better diagnostics in debugfs.
1897 * They're called even less than the "set direction" calls.
1898 */
1899static int gpiod_request_commit(struct gpio_desc *desc, const char *label)
1900{
1901 struct gpio_chip *gc = desc->gdev->chip;
1902 int ret;
1903 unsigned long flags;
1904 unsigned offset;
1905
1906 if (label) {
1907 label = kstrdup_const(label, GFP_KERNEL);
1908 if (!label)
1909 return -ENOMEM;
1910 }
1911
1912 spin_lock_irqsave(&gpio_lock, flags);
1913
1914 /* NOTE: gpio_request() can be called in early boot,
1915 * before IRQs are enabled, for non-sleeping (SOC) GPIOs.
1916 */
1917
1918 if (test_and_set_bit(FLAG_REQUESTED, &desc->flags) == 0) {
1919 desc_set_label(desc, label ? : "?");
1920 ret = 0;
1921 } else {
1922 kfree_const(label);
1923 ret = -EBUSY;
1924 goto done;
1925 }
1926
1927 if (gc->request) {
1928 /* gc->request may sleep */
1929 spin_unlock_irqrestore(&gpio_lock, flags);
1930 offset = gpio_chip_hwgpio(desc);
1931 if (gpiochip_line_is_valid(gc, offset))
1932 ret = gc->request(gc, offset);
1933 else
1934 ret = -EINVAL;
1935 spin_lock_irqsave(&gpio_lock, flags);
1936
1937 if (ret < 0) {
1938 desc_set_label(desc, NULL);
1939 kfree_const(label);
1940 clear_bit(FLAG_REQUESTED, &desc->flags);
1941 goto done;
1942 }
1943 }
1944 if (gc->get_direction) {
1945 /* gc->get_direction may sleep */
1946 spin_unlock_irqrestore(&gpio_lock, flags);
1947 gpiod_get_direction(desc);
1948 spin_lock_irqsave(&gpio_lock, flags);
1949 }
1950done:
1951 spin_unlock_irqrestore(&gpio_lock, flags);
1952 return ret;
1953}
1954
1955/*
1956 * This descriptor validation needs to be inserted verbatim into each
1957 * function taking a descriptor, so we need to use a preprocessor
1958 * macro to avoid endless duplication. If the desc is NULL it is an
1959 * optional GPIO and calls should just bail out.
1960 */
1961static int validate_desc(const struct gpio_desc *desc, const char *func)
1962{
1963 if (!desc)
1964 return 0;
1965 if (IS_ERR(desc)) {
1966 pr_warn("%s: invalid GPIO (errorpointer)\n", func);
1967 return PTR_ERR(desc);
1968 }
1969 if (!desc->gdev) {
1970 pr_warn("%s: invalid GPIO (no device)\n", func);
1971 return -EINVAL;
1972 }
1973 if (!desc->gdev->chip) {
1974 dev_warn(&desc->gdev->dev,
1975 "%s: backing chip is gone\n", func);
1976 return 0;
1977 }
1978 return 1;
1979}
1980
1981#define VALIDATE_DESC(desc) do { \
1982 int __valid = validate_desc(desc, __func__); \
1983 if (__valid <= 0) \
1984 return __valid; \
1985 } while (0)
1986
1987#define VALIDATE_DESC_VOID(desc) do { \
1988 int __valid = validate_desc(desc, __func__); \
1989 if (__valid <= 0) \
1990 return; \
1991 } while (0)
1992
1993int gpiod_request(struct gpio_desc *desc, const char *label)
1994{
1995 int ret = -EPROBE_DEFER;
1996 struct gpio_device *gdev;
1997
1998 VALIDATE_DESC(desc);
1999 gdev = desc->gdev;
2000
2001 if (try_module_get(gdev->owner)) {
2002 ret = gpiod_request_commit(desc, label);
2003 if (ret < 0)
2004 module_put(gdev->owner);
2005 else
2006 get_device(&gdev->dev);
2007 }
2008
2009 if (ret)
2010 gpiod_dbg(desc, "%s: status %d\n", __func__, ret);
2011
2012 return ret;
2013}
2014
2015static bool gpiod_free_commit(struct gpio_desc *desc)
2016{
2017 bool ret = false;
2018 unsigned long flags;
2019 struct gpio_chip *gc;
2020
2021 might_sleep();
2022
2023 gpiod_unexport(desc);
2024
2025 spin_lock_irqsave(&gpio_lock, flags);
2026
2027 gc = desc->gdev->chip;
2028 if (gc && test_bit(FLAG_REQUESTED, &desc->flags)) {
2029 if (gc->free) {
2030 spin_unlock_irqrestore(&gpio_lock, flags);
2031 might_sleep_if(gc->can_sleep);
2032 gc->free(gc, gpio_chip_hwgpio(desc));
2033 spin_lock_irqsave(&gpio_lock, flags);
2034 }
2035 kfree_const(desc->label);
2036 desc_set_label(desc, NULL);
2037 clear_bit(FLAG_ACTIVE_LOW, &desc->flags);
2038 clear_bit(FLAG_REQUESTED, &desc->flags);
2039 clear_bit(FLAG_OPEN_DRAIN, &desc->flags);
2040 clear_bit(FLAG_OPEN_SOURCE, &desc->flags);
2041 clear_bit(FLAG_PULL_UP, &desc->flags);
2042 clear_bit(FLAG_PULL_DOWN, &desc->flags);
2043 clear_bit(FLAG_BIAS_DISABLE, &desc->flags);
2044 clear_bit(FLAG_IS_HOGGED, &desc->flags);
2045#ifdef CONFIG_OF_DYNAMIC
2046 desc->hog = NULL;
2047#endif
2048 ret = true;
2049 }
2050
2051 spin_unlock_irqrestore(&gpio_lock, flags);
2052 blocking_notifier_call_chain(&desc->gdev->notifier,
2053 GPIOLINE_CHANGED_RELEASED, desc);
2054
2055 return ret;
2056}
2057
2058void gpiod_free(struct gpio_desc *desc)
2059{
2060 if (desc && desc->gdev && gpiod_free_commit(desc)) {
2061 module_put(desc->gdev->owner);
2062 put_device(&desc->gdev->dev);
2063 } else {
2064 WARN_ON(extra_checks);
2065 }
2066}
2067
2068/**
2069 * gpiochip_is_requested - return string iff signal was requested
2070 * @gc: controller managing the signal
2071 * @offset: of signal within controller's 0..(ngpio - 1) range
2072 *
2073 * Returns NULL if the GPIO is not currently requested, else a string.
2074 * The string returned is the label passed to gpio_request(); if none has been
2075 * passed it is a meaningless, non-NULL constant.
2076 *
2077 * This function is for use by GPIO controller drivers. The label can
2078 * help with diagnostics, and knowing that the signal is used as a GPIO
2079 * can help avoid accidentally multiplexing it to another controller.
2080 */
2081const char *gpiochip_is_requested(struct gpio_chip *gc, unsigned offset)
2082{
2083 struct gpio_desc *desc;
2084
2085 if (offset >= gc->ngpio)
2086 return NULL;
2087
2088 desc = gpiochip_get_desc(gc, offset);
2089 if (IS_ERR(desc))
2090 return NULL;
2091
2092 if (test_bit(FLAG_REQUESTED, &desc->flags) == 0)
2093 return NULL;
2094 return desc->label;
2095}
2096EXPORT_SYMBOL_GPL(gpiochip_is_requested);
2097
2098/**
2099 * gpiochip_request_own_desc - Allow GPIO chip to request its own descriptor
2100 * @gc: GPIO chip
2101 * @hwnum: hardware number of the GPIO for which to request the descriptor
2102 * @label: label for the GPIO
2103 * @lflags: lookup flags for this GPIO or 0 if default, this can be used to
2104 * specify things like line inversion semantics with the machine flags
2105 * such as GPIO_OUT_LOW
2106 * @dflags: descriptor request flags for this GPIO or 0 if default, this
2107 * can be used to specify consumer semantics such as open drain
2108 *
2109 * Function allows GPIO chip drivers to request and use their own GPIO
2110 * descriptors via gpiolib API. Difference to gpiod_request() is that this
2111 * function will not increase reference count of the GPIO chip module. This
2112 * allows the GPIO chip module to be unloaded as needed (we assume that the
2113 * GPIO chip driver handles freeing the GPIOs it has requested).
2114 *
2115 * Returns:
2116 * A pointer to the GPIO descriptor, or an ERR_PTR()-encoded negative error
2117 * code on failure.
2118 */
2119struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *gc,
2120 unsigned int hwnum,
2121 const char *label,
2122 enum gpio_lookup_flags lflags,
2123 enum gpiod_flags dflags)
2124{
2125 struct gpio_desc *desc = gpiochip_get_desc(gc, hwnum);
2126 int ret;
2127
2128 if (IS_ERR(desc)) {
2129 chip_err(gc, "failed to get GPIO descriptor\n");
2130 return desc;
2131 }
2132
2133 ret = gpiod_request_commit(desc, label);
2134 if (ret < 0)
2135 return ERR_PTR(ret);
2136
2137 ret = gpiod_configure_flags(desc, label, lflags, dflags);
2138 if (ret) {
2139 chip_err(gc, "setup of own GPIO %s failed\n", label);
2140 gpiod_free_commit(desc);
2141 return ERR_PTR(ret);
2142 }
2143
2144 return desc;
2145}
2146EXPORT_SYMBOL_GPL(gpiochip_request_own_desc);
2147
2148/**
2149 * gpiochip_free_own_desc - Free GPIO requested by the chip driver
2150 * @desc: GPIO descriptor to free
2151 *
2152 * Function frees the given GPIO requested previously with
2153 * gpiochip_request_own_desc().
2154 */
2155void gpiochip_free_own_desc(struct gpio_desc *desc)
2156{
2157 if (desc)
2158 gpiod_free_commit(desc);
2159}
2160EXPORT_SYMBOL_GPL(gpiochip_free_own_desc);
2161
2162/*
2163 * Drivers MUST set GPIO direction before making get/set calls. In
2164 * some cases this is done in early boot, before IRQs are enabled.
2165 *
2166 * As a rule these aren't called more than once (except for drivers
2167 * using the open-drain emulation idiom) so these are natural places
2168 * to accumulate extra debugging checks. Note that we can't (yet)
2169 * rely on gpio_request() having been called beforehand.
2170 */
2171
2172static int gpio_do_set_config(struct gpio_chip *gc, unsigned int offset,
2173 unsigned long config)
2174{
2175 if (!gc->set_config)
2176 return -ENOTSUPP;
2177
2178 return gc->set_config(gc, offset, config);
2179}
2180
2181static int gpio_set_config(struct gpio_desc *desc, enum pin_config_param mode)
2182{
2183 struct gpio_chip *gc = desc->gdev->chip;
2184 unsigned long config;
2185 unsigned arg;
2186
2187 switch (mode) {
2188 case PIN_CONFIG_BIAS_PULL_DOWN:
2189 case PIN_CONFIG_BIAS_PULL_UP:
2190 arg = 1;
2191 break;
2192
2193 default:
2194 arg = 0;
2195 }
2196
2197 config = PIN_CONF_PACKED(mode, arg);
2198 return gpio_do_set_config(gc, gpio_chip_hwgpio(desc), config);
2199}
2200
2201static int gpio_set_bias(struct gpio_desc *desc)
2202{
2203 int bias = 0;
2204 int ret = 0;
2205
2206 if (test_bit(FLAG_BIAS_DISABLE, &desc->flags))
2207 bias = PIN_CONFIG_BIAS_DISABLE;
2208 else if (test_bit(FLAG_PULL_UP, &desc->flags))
2209 bias = PIN_CONFIG_BIAS_PULL_UP;
2210 else if (test_bit(FLAG_PULL_DOWN, &desc->flags))
2211 bias = PIN_CONFIG_BIAS_PULL_DOWN;
2212
2213 if (bias) {
2214 ret = gpio_set_config(desc, bias);
2215 if (ret != -ENOTSUPP)
2216 return ret;
2217 }
2218 return 0;
2219}
2220
2221/**
2222 * gpiod_direction_input - set the GPIO direction to input
2223 * @desc: GPIO to set to input
2224 *
2225 * Set the direction of the passed GPIO to input, such as gpiod_get_value() can
2226 * be called safely on it.
2227 *
2228 * Return 0 in case of success, else an error code.
2229 */
2230int gpiod_direction_input(struct gpio_desc *desc)
2231{
2232 struct gpio_chip *gc;
2233 int ret = 0;
2234
2235 VALIDATE_DESC(desc);
2236 gc = desc->gdev->chip;
2237
2238 /*
2239 * It is legal to have no .get() and .direction_input() specified if
2240 * the chip is output-only, but you can't specify .direction_input()
2241 * and not support the .get() operation, that doesn't make sense.
2242 */
2243 if (!gc->get && gc->direction_input) {
2244 gpiod_warn(desc,
2245 "%s: missing get() but have direction_input()\n",
2246 __func__);
2247 return -EIO;
2248 }
2249
2250 /*
2251 * If we have a .direction_input() callback, things are simple,
2252 * just call it. Else we are some input-only chip so try to check the
2253 * direction (if .get_direction() is supported) else we silently
2254 * assume we are in input mode after this.
2255 */
2256 if (gc->direction_input) {
2257 ret = gc->direction_input(gc, gpio_chip_hwgpio(desc));
2258 } else if (gc->get_direction &&
2259 (gc->get_direction(gc, gpio_chip_hwgpio(desc)) != 1)) {
2260 gpiod_warn(desc,
2261 "%s: missing direction_input() operation and line is output\n",
2262 __func__);
2263 return -EIO;
2264 }
2265 if (ret == 0) {
2266 clear_bit(FLAG_IS_OUT, &desc->flags);
2267 ret = gpio_set_bias(desc);
2268 }
2269
2270 trace_gpio_direction(desc_to_gpio(desc), 1, ret);
2271
2272 return ret;
2273}
2274EXPORT_SYMBOL_GPL(gpiod_direction_input);
2275
2276static int gpiod_direction_output_raw_commit(struct gpio_desc *desc, int value)
2277{
2278 struct gpio_chip *gc = desc->gdev->chip;
2279 int val = !!value;
2280 int ret = 0;
2281
2282 /*
2283 * It's OK not to specify .direction_output() if the gpiochip is
2284 * output-only, but if there is then not even a .set() operation it
2285 * is pretty tricky to drive the output line.
2286 */
2287 if (!gc->set && !gc->direction_output) {
2288 gpiod_warn(desc,
2289 "%s: missing set() and direction_output() operations\n",
2290 __func__);
2291 return -EIO;
2292 }
2293
2294 if (gc->direction_output) {
2295 ret = gc->direction_output(gc, gpio_chip_hwgpio(desc), val);
2296 } else {
2297 /* Check that we are in output mode if we can */
2298 if (gc->get_direction &&
2299 gc->get_direction(gc, gpio_chip_hwgpio(desc))) {
2300 gpiod_warn(desc,
2301 "%s: missing direction_output() operation\n",
2302 __func__);
2303 return -EIO;
2304 }
2305 /*
2306 * If we can't actively set the direction, we are some
2307 * output-only chip, so just drive the output as desired.
2308 */
2309 gc->set(gc, gpio_chip_hwgpio(desc), val);
2310 }
2311
2312 if (!ret)
2313 set_bit(FLAG_IS_OUT, &desc->flags);
2314 trace_gpio_value(desc_to_gpio(desc), 0, val);
2315 trace_gpio_direction(desc_to_gpio(desc), 0, ret);
2316 return ret;
2317}
2318
2319/**
2320 * gpiod_direction_output_raw - set the GPIO direction to output
2321 * @desc: GPIO to set to output
2322 * @value: initial output value of the GPIO
2323 *
2324 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
2325 * be called safely on it. The initial value of the output must be specified
2326 * as raw value on the physical line without regard for the ACTIVE_LOW status.
2327 *
2328 * Return 0 in case of success, else an error code.
2329 */
2330int gpiod_direction_output_raw(struct gpio_desc *desc, int value)
2331{
2332 VALIDATE_DESC(desc);
2333 return gpiod_direction_output_raw_commit(desc, value);
2334}
2335EXPORT_SYMBOL_GPL(gpiod_direction_output_raw);
2336
2337/**
2338 * gpiod_direction_output - set the GPIO direction to output
2339 * @desc: GPIO to set to output
2340 * @value: initial output value of the GPIO
2341 *
2342 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
2343 * be called safely on it. The initial value of the output must be specified
2344 * as the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
2345 * account.
2346 *
2347 * Return 0 in case of success, else an error code.
2348 */
2349int gpiod_direction_output(struct gpio_desc *desc, int value)
2350{
2351 int ret;
2352
2353 VALIDATE_DESC(desc);
2354 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
2355 value = !value;
2356 else
2357 value = !!value;
2358
2359 /* GPIOs used for enabled IRQs shall not be set as output */
2360 if (test_bit(FLAG_USED_AS_IRQ, &desc->flags) &&
2361 test_bit(FLAG_IRQ_IS_ENABLED, &desc->flags)) {
2362 gpiod_err(desc,
2363 "%s: tried to set a GPIO tied to an IRQ as output\n",
2364 __func__);
2365 return -EIO;
2366 }
2367
2368 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) {
2369 /* First see if we can enable open drain in hardware */
2370 ret = gpio_set_config(desc, PIN_CONFIG_DRIVE_OPEN_DRAIN);
2371 if (!ret)
2372 goto set_output_value;
2373 /* Emulate open drain by not actively driving the line high */
2374 if (value) {
2375 ret = gpiod_direction_input(desc);
2376 goto set_output_flag;
2377 }
2378 }
2379 else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) {
2380 ret = gpio_set_config(desc, PIN_CONFIG_DRIVE_OPEN_SOURCE);
2381 if (!ret)
2382 goto set_output_value;
2383 /* Emulate open source by not actively driving the line low */
2384 if (!value) {
2385 ret = gpiod_direction_input(desc);
2386 goto set_output_flag;
2387 }
2388 } else {
2389 gpio_set_config(desc, PIN_CONFIG_DRIVE_PUSH_PULL);
2390 }
2391
2392set_output_value:
2393 ret = gpio_set_bias(desc);
2394 if (ret)
2395 return ret;
2396 return gpiod_direction_output_raw_commit(desc, value);
2397
2398set_output_flag:
2399 /*
2400 * When emulating open-source or open-drain functionalities by not
2401 * actively driving the line (setting mode to input) we still need to
2402 * set the IS_OUT flag or otherwise we won't be able to set the line
2403 * value anymore.
2404 */
2405 if (ret == 0)
2406 set_bit(FLAG_IS_OUT, &desc->flags);
2407 return ret;
2408}
2409EXPORT_SYMBOL_GPL(gpiod_direction_output);
2410
2411/**
2412 * gpiod_set_config - sets @config for a GPIO
2413 * @desc: descriptor of the GPIO for which to set the configuration
2414 * @config: Same packed config format as generic pinconf
2415 *
2416 * Returns:
2417 * 0 on success, %-ENOTSUPP if the controller doesn't support setting the
2418 * configuration.
2419 */
2420int gpiod_set_config(struct gpio_desc *desc, unsigned long config)
2421{
2422 struct gpio_chip *gc;
2423
2424 VALIDATE_DESC(desc);
2425 gc = desc->gdev->chip;
2426
2427 return gpio_do_set_config(gc, gpio_chip_hwgpio(desc), config);
2428}
2429EXPORT_SYMBOL_GPL(gpiod_set_config);
2430
2431/**
2432 * gpiod_set_debounce - sets @debounce time for a GPIO
2433 * @desc: descriptor of the GPIO for which to set debounce time
2434 * @debounce: debounce time in microseconds
2435 *
2436 * Returns:
2437 * 0 on success, %-ENOTSUPP if the controller doesn't support setting the
2438 * debounce time.
2439 */
2440int gpiod_set_debounce(struct gpio_desc *desc, unsigned debounce)
2441{
2442 unsigned long config;
2443
2444 config = pinconf_to_config_packed(PIN_CONFIG_INPUT_DEBOUNCE, debounce);
2445 return gpiod_set_config(desc, config);
2446}
2447EXPORT_SYMBOL_GPL(gpiod_set_debounce);
2448
2449/**
2450 * gpiod_set_transitory - Lose or retain GPIO state on suspend or reset
2451 * @desc: descriptor of the GPIO for which to configure persistence
2452 * @transitory: True to lose state on suspend or reset, false for persistence
2453 *
2454 * Returns:
2455 * 0 on success, otherwise a negative error code.
2456 */
2457int gpiod_set_transitory(struct gpio_desc *desc, bool transitory)
2458{
2459 struct gpio_chip *gc;
2460 unsigned long packed;
2461 int gpio;
2462 int rc;
2463
2464 VALIDATE_DESC(desc);
2465 /*
2466 * Handle FLAG_TRANSITORY first, enabling queries to gpiolib for
2467 * persistence state.
2468 */
2469 assign_bit(FLAG_TRANSITORY, &desc->flags, transitory);
2470
2471 /* If the driver supports it, set the persistence state now */
2472 gc = desc->gdev->chip;
2473 if (!gc->set_config)
2474 return 0;
2475
2476 packed = pinconf_to_config_packed(PIN_CONFIG_PERSIST_STATE,
2477 !transitory);
2478 gpio = gpio_chip_hwgpio(desc);
2479 rc = gpio_do_set_config(gc, gpio, packed);
2480 if (rc == -ENOTSUPP) {
2481 dev_dbg(&desc->gdev->dev, "Persistence not supported for GPIO %d\n",
2482 gpio);
2483 return 0;
2484 }
2485
2486 return rc;
2487}
2488EXPORT_SYMBOL_GPL(gpiod_set_transitory);
2489
2490/**
2491 * gpiod_is_active_low - test whether a GPIO is active-low or not
2492 * @desc: the gpio descriptor to test
2493 *
2494 * Returns 1 if the GPIO is active-low, 0 otherwise.
2495 */
2496int gpiod_is_active_low(const struct gpio_desc *desc)
2497{
2498 VALIDATE_DESC(desc);
2499 return test_bit(FLAG_ACTIVE_LOW, &desc->flags);
2500}
2501EXPORT_SYMBOL_GPL(gpiod_is_active_low);
2502
2503/**
2504 * gpiod_toggle_active_low - toggle whether a GPIO is active-low or not
2505 * @desc: the gpio descriptor to change
2506 */
2507void gpiod_toggle_active_low(struct gpio_desc *desc)
2508{
2509 VALIDATE_DESC_VOID(desc);
2510 change_bit(FLAG_ACTIVE_LOW, &desc->flags);
2511}
2512EXPORT_SYMBOL_GPL(gpiod_toggle_active_low);
2513
2514/* I/O calls are only valid after configuration completed; the relevant
2515 * "is this a valid GPIO" error checks should already have been done.
2516 *
2517 * "Get" operations are often inlinable as reading a pin value register,
2518 * and masking the relevant bit in that register.
2519 *
2520 * When "set" operations are inlinable, they involve writing that mask to
2521 * one register to set a low value, or a different register to set it high.
2522 * Otherwise locking is needed, so there may be little value to inlining.
2523 *
2524 *------------------------------------------------------------------------
2525 *
2526 * IMPORTANT!!! The hot paths -- get/set value -- assume that callers
2527 * have requested the GPIO. That can include implicit requesting by
2528 * a direction setting call. Marking a gpio as requested locks its chip
2529 * in memory, guaranteeing that these table lookups need no more locking
2530 * and that gpiochip_remove() will fail.
2531 *
2532 * REVISIT when debugging, consider adding some instrumentation to ensure
2533 * that the GPIO was actually requested.
2534 */
2535
2536static int gpiod_get_raw_value_commit(const struct gpio_desc *desc)
2537{
2538 struct gpio_chip *gc;
2539 int offset;
2540 int value;
2541
2542 gc = desc->gdev->chip;
2543 offset = gpio_chip_hwgpio(desc);
2544 value = gc->get ? gc->get(gc, offset) : -EIO;
2545 value = value < 0 ? value : !!value;
2546 trace_gpio_value(desc_to_gpio(desc), 1, value);
2547 return value;
2548}
2549
2550static int gpio_chip_get_multiple(struct gpio_chip *gc,
2551 unsigned long *mask, unsigned long *bits)
2552{
2553 if (gc->get_multiple) {
2554 return gc->get_multiple(gc, mask, bits);
2555 } else if (gc->get) {
2556 int i, value;
2557
2558 for_each_set_bit(i, mask, gc->ngpio) {
2559 value = gc->get(gc, i);
2560 if (value < 0)
2561 return value;
2562 __assign_bit(i, bits, value);
2563 }
2564 return 0;
2565 }
2566 return -EIO;
2567}
2568
2569int gpiod_get_array_value_complex(bool raw, bool can_sleep,
2570 unsigned int array_size,
2571 struct gpio_desc **desc_array,
2572 struct gpio_array *array_info,
2573 unsigned long *value_bitmap)
2574{
2575 int ret, i = 0;
2576
2577 /*
2578 * Validate array_info against desc_array and its size.
2579 * It should immediately follow desc_array if both
2580 * have been obtained from the same gpiod_get_array() call.
2581 */
2582 if (array_info && array_info->desc == desc_array &&
2583 array_size <= array_info->size &&
2584 (void *)array_info == desc_array + array_info->size) {
2585 if (!can_sleep)
2586 WARN_ON(array_info->chip->can_sleep);
2587
2588 ret = gpio_chip_get_multiple(array_info->chip,
2589 array_info->get_mask,
2590 value_bitmap);
2591 if (ret)
2592 return ret;
2593
2594 if (!raw && !bitmap_empty(array_info->invert_mask, array_size))
2595 bitmap_xor(value_bitmap, value_bitmap,
2596 array_info->invert_mask, array_size);
2597
2598 i = find_first_zero_bit(array_info->get_mask, array_size);
2599 if (i == array_size)
2600 return 0;
2601 } else {
2602 array_info = NULL;
2603 }
2604
2605 while (i < array_size) {
2606 struct gpio_chip *gc = desc_array[i]->gdev->chip;
2607 unsigned long fastpath[2 * BITS_TO_LONGS(FASTPATH_NGPIO)];
2608 unsigned long *mask, *bits;
2609 int first, j, ret;
2610
2611 if (likely(gc->ngpio <= FASTPATH_NGPIO)) {
2612 mask = fastpath;
2613 } else {
2614 mask = kmalloc_array(2 * BITS_TO_LONGS(gc->ngpio),
2615 sizeof(*mask),
2616 can_sleep ? GFP_KERNEL : GFP_ATOMIC);
2617 if (!mask)
2618 return -ENOMEM;
2619 }
2620
2621 bits = mask + BITS_TO_LONGS(gc->ngpio);
2622 bitmap_zero(mask, gc->ngpio);
2623
2624 if (!can_sleep)
2625 WARN_ON(gc->can_sleep);
2626
2627 /* collect all inputs belonging to the same chip */
2628 first = i;
2629 do {
2630 const struct gpio_desc *desc = desc_array[i];
2631 int hwgpio = gpio_chip_hwgpio(desc);
2632
2633 __set_bit(hwgpio, mask);
2634 i++;
2635
2636 if (array_info)
2637 i = find_next_zero_bit(array_info->get_mask,
2638 array_size, i);
2639 } while ((i < array_size) &&
2640 (desc_array[i]->gdev->chip == gc));
2641
2642 ret = gpio_chip_get_multiple(gc, mask, bits);
2643 if (ret) {
2644 if (mask != fastpath)
2645 kfree(mask);
2646 return ret;
2647 }
2648
2649 for (j = first; j < i; ) {
2650 const struct gpio_desc *desc = desc_array[j];
2651 int hwgpio = gpio_chip_hwgpio(desc);
2652 int value = test_bit(hwgpio, bits);
2653
2654 if (!raw && test_bit(FLAG_ACTIVE_LOW, &desc->flags))
2655 value = !value;
2656 __assign_bit(j, value_bitmap, value);
2657 trace_gpio_value(desc_to_gpio(desc), 1, value);
2658 j++;
2659
2660 if (array_info)
2661 j = find_next_zero_bit(array_info->get_mask, i,
2662 j);
2663 }
2664
2665 if (mask != fastpath)
2666 kfree(mask);
2667 }
2668 return 0;
2669}
2670
2671/**
2672 * gpiod_get_raw_value() - return a gpio's raw value
2673 * @desc: gpio whose value will be returned
2674 *
2675 * Return the GPIO's raw value, i.e. the value of the physical line disregarding
2676 * its ACTIVE_LOW status, or negative errno on failure.
2677 *
2678 * This function can be called from contexts where we cannot sleep, and will
2679 * complain if the GPIO chip functions potentially sleep.
2680 */
2681int gpiod_get_raw_value(const struct gpio_desc *desc)
2682{
2683 VALIDATE_DESC(desc);
2684 /* Should be using gpiod_get_raw_value_cansleep() */
2685 WARN_ON(desc->gdev->chip->can_sleep);
2686 return gpiod_get_raw_value_commit(desc);
2687}
2688EXPORT_SYMBOL_GPL(gpiod_get_raw_value);
2689
2690/**
2691 * gpiod_get_value() - return a gpio's value
2692 * @desc: gpio whose value will be returned
2693 *
2694 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
2695 * account, or negative errno on failure.
2696 *
2697 * This function can be called from contexts where we cannot sleep, and will
2698 * complain if the GPIO chip functions potentially sleep.
2699 */
2700int gpiod_get_value(const struct gpio_desc *desc)
2701{
2702 int value;
2703
2704 VALIDATE_DESC(desc);
2705 /* Should be using gpiod_get_value_cansleep() */
2706 WARN_ON(desc->gdev->chip->can_sleep);
2707
2708 value = gpiod_get_raw_value_commit(desc);
2709 if (value < 0)
2710 return value;
2711
2712 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
2713 value = !value;
2714
2715 return value;
2716}
2717EXPORT_SYMBOL_GPL(gpiod_get_value);
2718
2719/**
2720 * gpiod_get_raw_array_value() - read raw values from an array of GPIOs
2721 * @array_size: number of elements in the descriptor array / value bitmap
2722 * @desc_array: array of GPIO descriptors whose values will be read
2723 * @array_info: information on applicability of fast bitmap processing path
2724 * @value_bitmap: bitmap to store the read values
2725 *
2726 * Read the raw values of the GPIOs, i.e. the values of the physical lines
2727 * without regard for their ACTIVE_LOW status. Return 0 in case of success,
2728 * else an error code.
2729 *
2730 * This function can be called from contexts where we cannot sleep,
2731 * and it will complain if the GPIO chip functions potentially sleep.
2732 */
2733int gpiod_get_raw_array_value(unsigned int array_size,
2734 struct gpio_desc **desc_array,
2735 struct gpio_array *array_info,
2736 unsigned long *value_bitmap)
2737{
2738 if (!desc_array)
2739 return -EINVAL;
2740 return gpiod_get_array_value_complex(true, false, array_size,
2741 desc_array, array_info,
2742 value_bitmap);
2743}
2744EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value);
2745
2746/**
2747 * gpiod_get_array_value() - read values from an array of GPIOs
2748 * @array_size: number of elements in the descriptor array / value bitmap
2749 * @desc_array: array of GPIO descriptors whose values will be read
2750 * @array_info: information on applicability of fast bitmap processing path
2751 * @value_bitmap: bitmap to store the read values
2752 *
2753 * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
2754 * into account. Return 0 in case of success, else an error code.
2755 *
2756 * This function can be called from contexts where we cannot sleep,
2757 * and it will complain if the GPIO chip functions potentially sleep.
2758 */
2759int gpiod_get_array_value(unsigned int array_size,
2760 struct gpio_desc **desc_array,
2761 struct gpio_array *array_info,
2762 unsigned long *value_bitmap)
2763{
2764 if (!desc_array)
2765 return -EINVAL;
2766 return gpiod_get_array_value_complex(false, false, array_size,
2767 desc_array, array_info,
2768 value_bitmap);
2769}
2770EXPORT_SYMBOL_GPL(gpiod_get_array_value);
2771
2772/*
2773 * gpio_set_open_drain_value_commit() - Set the open drain gpio's value.
2774 * @desc: gpio descriptor whose state need to be set.
2775 * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
2776 */
2777static void gpio_set_open_drain_value_commit(struct gpio_desc *desc, bool value)
2778{
2779 int ret = 0;
2780 struct gpio_chip *gc = desc->gdev->chip;
2781 int offset = gpio_chip_hwgpio(desc);
2782
2783 if (value) {
2784 ret = gc->direction_input(gc, offset);
2785 } else {
2786 ret = gc->direction_output(gc, offset, 0);
2787 if (!ret)
2788 set_bit(FLAG_IS_OUT, &desc->flags);
2789 }
2790 trace_gpio_direction(desc_to_gpio(desc), value, ret);
2791 if (ret < 0)
2792 gpiod_err(desc,
2793 "%s: Error in set_value for open drain err %d\n",
2794 __func__, ret);
2795}
2796
2797/*
2798 * _gpio_set_open_source_value() - Set the open source gpio's value.
2799 * @desc: gpio descriptor whose state need to be set.
2800 * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
2801 */
2802static void gpio_set_open_source_value_commit(struct gpio_desc *desc, bool value)
2803{
2804 int ret = 0;
2805 struct gpio_chip *gc = desc->gdev->chip;
2806 int offset = gpio_chip_hwgpio(desc);
2807
2808 if (value) {
2809 ret = gc->direction_output(gc, offset, 1);
2810 if (!ret)
2811 set_bit(FLAG_IS_OUT, &desc->flags);
2812 } else {
2813 ret = gc->direction_input(gc, offset);
2814 }
2815 trace_gpio_direction(desc_to_gpio(desc), !value, ret);
2816 if (ret < 0)
2817 gpiod_err(desc,
2818 "%s: Error in set_value for open source err %d\n",
2819 __func__, ret);
2820}
2821
2822static void gpiod_set_raw_value_commit(struct gpio_desc *desc, bool value)
2823{
2824 struct gpio_chip *gc;
2825
2826 gc = desc->gdev->chip;
2827 trace_gpio_value(desc_to_gpio(desc), 0, value);
2828 gc->set(gc, gpio_chip_hwgpio(desc), value);
2829}
2830
2831/*
2832 * set multiple outputs on the same chip;
2833 * use the chip's set_multiple function if available;
2834 * otherwise set the outputs sequentially;
2835 * @chip: the GPIO chip we operate on
2836 * @mask: bit mask array; one bit per output; BITS_PER_LONG bits per word
2837 * defines which outputs are to be changed
2838 * @bits: bit value array; one bit per output; BITS_PER_LONG bits per word
2839 * defines the values the outputs specified by mask are to be set to
2840 */
2841static void gpio_chip_set_multiple(struct gpio_chip *gc,
2842 unsigned long *mask, unsigned long *bits)
2843{
2844 if (gc->set_multiple) {
2845 gc->set_multiple(gc, mask, bits);
2846 } else {
2847 unsigned int i;
2848
2849 /* set outputs if the corresponding mask bit is set */
2850 for_each_set_bit(i, mask, gc->ngpio)
2851 gc->set(gc, i, test_bit(i, bits));
2852 }
2853}
2854
2855int gpiod_set_array_value_complex(bool raw, bool can_sleep,
2856 unsigned int array_size,
2857 struct gpio_desc **desc_array,
2858 struct gpio_array *array_info,
2859 unsigned long *value_bitmap)
2860{
2861 int i = 0;
2862
2863 /*
2864 * Validate array_info against desc_array and its size.
2865 * It should immediately follow desc_array if both
2866 * have been obtained from the same gpiod_get_array() call.
2867 */
2868 if (array_info && array_info->desc == desc_array &&
2869 array_size <= array_info->size &&
2870 (void *)array_info == desc_array + array_info->size) {
2871 if (!can_sleep)
2872 WARN_ON(array_info->chip->can_sleep);
2873
2874 if (!raw && !bitmap_empty(array_info->invert_mask, array_size))
2875 bitmap_xor(value_bitmap, value_bitmap,
2876 array_info->invert_mask, array_size);
2877
2878 gpio_chip_set_multiple(array_info->chip, array_info->set_mask,
2879 value_bitmap);
2880
2881 i = find_first_zero_bit(array_info->set_mask, array_size);
2882 if (i == array_size)
2883 return 0;
2884 } else {
2885 array_info = NULL;
2886 }
2887
2888 while (i < array_size) {
2889 struct gpio_chip *gc = desc_array[i]->gdev->chip;
2890 unsigned long fastpath[2 * BITS_TO_LONGS(FASTPATH_NGPIO)];
2891 unsigned long *mask, *bits;
2892 int count = 0;
2893
2894 if (likely(gc->ngpio <= FASTPATH_NGPIO)) {
2895 mask = fastpath;
2896 } else {
2897 mask = kmalloc_array(2 * BITS_TO_LONGS(gc->ngpio),
2898 sizeof(*mask),
2899 can_sleep ? GFP_KERNEL : GFP_ATOMIC);
2900 if (!mask)
2901 return -ENOMEM;
2902 }
2903
2904 bits = mask + BITS_TO_LONGS(gc->ngpio);
2905 bitmap_zero(mask, gc->ngpio);
2906
2907 if (!can_sleep)
2908 WARN_ON(gc->can_sleep);
2909
2910 do {
2911 struct gpio_desc *desc = desc_array[i];
2912 int hwgpio = gpio_chip_hwgpio(desc);
2913 int value = test_bit(i, value_bitmap);
2914
2915 /*
2916 * Pins applicable for fast input but not for
2917 * fast output processing may have been already
2918 * inverted inside the fast path, skip them.
2919 */
2920 if (!raw && !(array_info &&
2921 test_bit(i, array_info->invert_mask)) &&
2922 test_bit(FLAG_ACTIVE_LOW, &desc->flags))
2923 value = !value;
2924 trace_gpio_value(desc_to_gpio(desc), 0, value);
2925 /*
2926 * collect all normal outputs belonging to the same chip
2927 * open drain and open source outputs are set individually
2928 */
2929 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags) && !raw) {
2930 gpio_set_open_drain_value_commit(desc, value);
2931 } else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags) && !raw) {
2932 gpio_set_open_source_value_commit(desc, value);
2933 } else {
2934 __set_bit(hwgpio, mask);
2935 __assign_bit(hwgpio, bits, value);
2936 count++;
2937 }
2938 i++;
2939
2940 if (array_info)
2941 i = find_next_zero_bit(array_info->set_mask,
2942 array_size, i);
2943 } while ((i < array_size) &&
2944 (desc_array[i]->gdev->chip == gc));
2945 /* push collected bits to outputs */
2946 if (count != 0)
2947 gpio_chip_set_multiple(gc, mask, bits);
2948
2949 if (mask != fastpath)
2950 kfree(mask);
2951 }
2952 return 0;
2953}
2954
2955/**
2956 * gpiod_set_raw_value() - assign a gpio's raw value
2957 * @desc: gpio whose value will be assigned
2958 * @value: value to assign
2959 *
2960 * Set the raw value of the GPIO, i.e. the value of its physical line without
2961 * regard for its ACTIVE_LOW status.
2962 *
2963 * This function can be called from contexts where we cannot sleep, and will
2964 * complain if the GPIO chip functions potentially sleep.
2965 */
2966void gpiod_set_raw_value(struct gpio_desc *desc, int value)
2967{
2968 VALIDATE_DESC_VOID(desc);
2969 /* Should be using gpiod_set_raw_value_cansleep() */
2970 WARN_ON(desc->gdev->chip->can_sleep);
2971 gpiod_set_raw_value_commit(desc, value);
2972}
2973EXPORT_SYMBOL_GPL(gpiod_set_raw_value);
2974
2975/**
2976 * gpiod_set_value_nocheck() - set a GPIO line value without checking
2977 * @desc: the descriptor to set the value on
2978 * @value: value to set
2979 *
2980 * This sets the value of a GPIO line backing a descriptor, applying
2981 * different semantic quirks like active low and open drain/source
2982 * handling.
2983 */
2984static void gpiod_set_value_nocheck(struct gpio_desc *desc, int value)
2985{
2986 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
2987 value = !value;
2988 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags))
2989 gpio_set_open_drain_value_commit(desc, value);
2990 else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags))
2991 gpio_set_open_source_value_commit(desc, value);
2992 else
2993 gpiod_set_raw_value_commit(desc, value);
2994}
2995
2996/**
2997 * gpiod_set_value() - assign a gpio's value
2998 * @desc: gpio whose value will be assigned
2999 * @value: value to assign
3000 *
3001 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW,
3002 * OPEN_DRAIN and OPEN_SOURCE flags into account.
3003 *
3004 * This function can be called from contexts where we cannot sleep, and will
3005 * complain if the GPIO chip functions potentially sleep.
3006 */
3007void gpiod_set_value(struct gpio_desc *desc, int value)
3008{
3009 VALIDATE_DESC_VOID(desc);
3010 /* Should be using gpiod_set_value_cansleep() */
3011 WARN_ON(desc->gdev->chip->can_sleep);
3012 gpiod_set_value_nocheck(desc, value);
3013}
3014EXPORT_SYMBOL_GPL(gpiod_set_value);
3015
3016/**
3017 * gpiod_set_raw_array_value() - assign values to an array of GPIOs
3018 * @array_size: number of elements in the descriptor array / value bitmap
3019 * @desc_array: array of GPIO descriptors whose values will be assigned
3020 * @array_info: information on applicability of fast bitmap processing path
3021 * @value_bitmap: bitmap of values to assign
3022 *
3023 * Set the raw values of the GPIOs, i.e. the values of the physical lines
3024 * without regard for their ACTIVE_LOW status.
3025 *
3026 * This function can be called from contexts where we cannot sleep, and will
3027 * complain if the GPIO chip functions potentially sleep.
3028 */
3029int gpiod_set_raw_array_value(unsigned int array_size,
3030 struct gpio_desc **desc_array,
3031 struct gpio_array *array_info,
3032 unsigned long *value_bitmap)
3033{
3034 if (!desc_array)
3035 return -EINVAL;
3036 return gpiod_set_array_value_complex(true, false, array_size,
3037 desc_array, array_info, value_bitmap);
3038}
3039EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value);
3040
3041/**
3042 * gpiod_set_array_value() - assign values to an array of GPIOs
3043 * @array_size: number of elements in the descriptor array / value bitmap
3044 * @desc_array: array of GPIO descriptors whose values will be assigned
3045 * @array_info: information on applicability of fast bitmap processing path
3046 * @value_bitmap: bitmap of values to assign
3047 *
3048 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3049 * into account.
3050 *
3051 * This function can be called from contexts where we cannot sleep, and will
3052 * complain if the GPIO chip functions potentially sleep.
3053 */
3054int gpiod_set_array_value(unsigned int array_size,
3055 struct gpio_desc **desc_array,
3056 struct gpio_array *array_info,
3057 unsigned long *value_bitmap)
3058{
3059 if (!desc_array)
3060 return -EINVAL;
3061 return gpiod_set_array_value_complex(false, false, array_size,
3062 desc_array, array_info,
3063 value_bitmap);
3064}
3065EXPORT_SYMBOL_GPL(gpiod_set_array_value);
3066
3067/**
3068 * gpiod_cansleep() - report whether gpio value access may sleep
3069 * @desc: gpio to check
3070 *
3071 */
3072int gpiod_cansleep(const struct gpio_desc *desc)
3073{
3074 VALIDATE_DESC(desc);
3075 return desc->gdev->chip->can_sleep;
3076}
3077EXPORT_SYMBOL_GPL(gpiod_cansleep);
3078
3079/**
3080 * gpiod_set_consumer_name() - set the consumer name for the descriptor
3081 * @desc: gpio to set the consumer name on
3082 * @name: the new consumer name
3083 */
3084int gpiod_set_consumer_name(struct gpio_desc *desc, const char *name)
3085{
3086 VALIDATE_DESC(desc);
3087 if (name) {
3088 name = kstrdup_const(name, GFP_KERNEL);
3089 if (!name)
3090 return -ENOMEM;
3091 }
3092
3093 kfree_const(desc->label);
3094 desc_set_label(desc, name);
3095
3096 return 0;
3097}
3098EXPORT_SYMBOL_GPL(gpiod_set_consumer_name);
3099
3100/**
3101 * gpiod_to_irq() - return the IRQ corresponding to a GPIO
3102 * @desc: gpio whose IRQ will be returned (already requested)
3103 *
3104 * Return the IRQ corresponding to the passed GPIO, or an error code in case of
3105 * error.
3106 */
3107int gpiod_to_irq(const struct gpio_desc *desc)
3108{
3109 struct gpio_chip *gc;
3110 int offset;
3111
3112 /*
3113 * Cannot VALIDATE_DESC() here as gpiod_to_irq() consumer semantics
3114 * requires this function to not return zero on an invalid descriptor
3115 * but rather a negative error number.
3116 */
3117 if (!desc || IS_ERR(desc) || !desc->gdev || !desc->gdev->chip)
3118 return -EINVAL;
3119
3120 gc = desc->gdev->chip;
3121 offset = gpio_chip_hwgpio(desc);
3122 if (gc->to_irq) {
3123 int retirq = gc->to_irq(gc, offset);
3124
3125 /* Zero means NO_IRQ */
3126 if (!retirq)
3127 return -ENXIO;
3128
3129 return retirq;
3130 }
3131 return -ENXIO;
3132}
3133EXPORT_SYMBOL_GPL(gpiod_to_irq);
3134
3135/**
3136 * gpiochip_lock_as_irq() - lock a GPIO to be used as IRQ
3137 * @gc: the chip the GPIO to lock belongs to
3138 * @offset: the offset of the GPIO to lock as IRQ
3139 *
3140 * This is used directly by GPIO drivers that want to lock down
3141 * a certain GPIO line to be used for IRQs.
3142 */
3143int gpiochip_lock_as_irq(struct gpio_chip *gc, unsigned int offset)
3144{
3145 struct gpio_desc *desc;
3146
3147 desc = gpiochip_get_desc(gc, offset);
3148 if (IS_ERR(desc))
3149 return PTR_ERR(desc);
3150
3151 /*
3152 * If it's fast: flush the direction setting if something changed
3153 * behind our back
3154 */
3155 if (!gc->can_sleep && gc->get_direction) {
3156 int dir = gpiod_get_direction(desc);
3157
3158 if (dir < 0) {
3159 chip_err(gc, "%s: cannot get GPIO direction\n",
3160 __func__);
3161 return dir;
3162 }
3163 }
3164
3165 /* To be valid for IRQ the line needs to be input or open drain */
3166 if (test_bit(FLAG_IS_OUT, &desc->flags) &&
3167 !test_bit(FLAG_OPEN_DRAIN, &desc->flags)) {
3168 chip_err(gc,
3169 "%s: tried to flag a GPIO set as output for IRQ\n",
3170 __func__);
3171 return -EIO;
3172 }
3173
3174 set_bit(FLAG_USED_AS_IRQ, &desc->flags);
3175 set_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
3176
3177 /*
3178 * If the consumer has not set up a label (such as when the
3179 * IRQ is referenced from .to_irq()) we set up a label here
3180 * so it is clear this is used as an interrupt.
3181 */
3182 if (!desc->label)
3183 desc_set_label(desc, "interrupt");
3184
3185 return 0;
3186}
3187EXPORT_SYMBOL_GPL(gpiochip_lock_as_irq);
3188
3189/**
3190 * gpiochip_unlock_as_irq() - unlock a GPIO used as IRQ
3191 * @gc: the chip the GPIO to lock belongs to
3192 * @offset: the offset of the GPIO to lock as IRQ
3193 *
3194 * This is used directly by GPIO drivers that want to indicate
3195 * that a certain GPIO is no longer used exclusively for IRQ.
3196 */
3197void gpiochip_unlock_as_irq(struct gpio_chip *gc, unsigned int offset)
3198{
3199 struct gpio_desc *desc;
3200
3201 desc = gpiochip_get_desc(gc, offset);
3202 if (IS_ERR(desc))
3203 return;
3204
3205 clear_bit(FLAG_USED_AS_IRQ, &desc->flags);
3206 clear_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
3207
3208 /* If we only had this marking, erase it */
3209 if (desc->label && !strcmp(desc->label, "interrupt"))
3210 desc_set_label(desc, NULL);
3211}
3212EXPORT_SYMBOL_GPL(gpiochip_unlock_as_irq);
3213
3214void gpiochip_disable_irq(struct gpio_chip *gc, unsigned int offset)
3215{
3216 struct gpio_desc *desc = gpiochip_get_desc(gc, offset);
3217
3218 if (!IS_ERR(desc) &&
3219 !WARN_ON(!test_bit(FLAG_USED_AS_IRQ, &desc->flags)))
3220 clear_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
3221}
3222EXPORT_SYMBOL_GPL(gpiochip_disable_irq);
3223
3224void gpiochip_enable_irq(struct gpio_chip *gc, unsigned int offset)
3225{
3226 struct gpio_desc *desc = gpiochip_get_desc(gc, offset);
3227
3228 if (!IS_ERR(desc) &&
3229 !WARN_ON(!test_bit(FLAG_USED_AS_IRQ, &desc->flags))) {
3230 /*
3231 * We must not be output when using IRQ UNLESS we are
3232 * open drain.
3233 */
3234 WARN_ON(test_bit(FLAG_IS_OUT, &desc->flags) &&
3235 !test_bit(FLAG_OPEN_DRAIN, &desc->flags));
3236 set_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
3237 }
3238}
3239EXPORT_SYMBOL_GPL(gpiochip_enable_irq);
3240
3241bool gpiochip_line_is_irq(struct gpio_chip *gc, unsigned int offset)
3242{
3243 if (offset >= gc->ngpio)
3244 return false;
3245
3246 return test_bit(FLAG_USED_AS_IRQ, &gc->gpiodev->descs[offset].flags);
3247}
3248EXPORT_SYMBOL_GPL(gpiochip_line_is_irq);
3249
3250int gpiochip_reqres_irq(struct gpio_chip *gc, unsigned int offset)
3251{
3252 int ret;
3253
3254 if (!try_module_get(gc->gpiodev->owner))
3255 return -ENODEV;
3256
3257 ret = gpiochip_lock_as_irq(gc, offset);
3258 if (ret) {
3259 chip_err(gc, "unable to lock HW IRQ %u for IRQ\n", offset);
3260 module_put(gc->gpiodev->owner);
3261 return ret;
3262 }
3263 return 0;
3264}
3265EXPORT_SYMBOL_GPL(gpiochip_reqres_irq);
3266
3267void gpiochip_relres_irq(struct gpio_chip *gc, unsigned int offset)
3268{
3269 gpiochip_unlock_as_irq(gc, offset);
3270 module_put(gc->gpiodev->owner);
3271}
3272EXPORT_SYMBOL_GPL(gpiochip_relres_irq);
3273
3274bool gpiochip_line_is_open_drain(struct gpio_chip *gc, unsigned int offset)
3275{
3276 if (offset >= gc->ngpio)
3277 return false;
3278
3279 return test_bit(FLAG_OPEN_DRAIN, &gc->gpiodev->descs[offset].flags);
3280}
3281EXPORT_SYMBOL_GPL(gpiochip_line_is_open_drain);
3282
3283bool gpiochip_line_is_open_source(struct gpio_chip *gc, unsigned int offset)
3284{
3285 if (offset >= gc->ngpio)
3286 return false;
3287
3288 return test_bit(FLAG_OPEN_SOURCE, &gc->gpiodev->descs[offset].flags);
3289}
3290EXPORT_SYMBOL_GPL(gpiochip_line_is_open_source);
3291
3292bool gpiochip_line_is_persistent(struct gpio_chip *gc, unsigned int offset)
3293{
3294 if (offset >= gc->ngpio)
3295 return false;
3296
3297 return !test_bit(FLAG_TRANSITORY, &gc->gpiodev->descs[offset].flags);
3298}
3299EXPORT_SYMBOL_GPL(gpiochip_line_is_persistent);
3300
3301/**
3302 * gpiod_get_raw_value_cansleep() - return a gpio's raw value
3303 * @desc: gpio whose value will be returned
3304 *
3305 * Return the GPIO's raw value, i.e. the value of the physical line disregarding
3306 * its ACTIVE_LOW status, or negative errno on failure.
3307 *
3308 * This function is to be called from contexts that can sleep.
3309 */
3310int gpiod_get_raw_value_cansleep(const struct gpio_desc *desc)
3311{
3312 might_sleep_if(extra_checks);
3313 VALIDATE_DESC(desc);
3314 return gpiod_get_raw_value_commit(desc);
3315}
3316EXPORT_SYMBOL_GPL(gpiod_get_raw_value_cansleep);
3317
3318/**
3319 * gpiod_get_value_cansleep() - return a gpio's value
3320 * @desc: gpio whose value will be returned
3321 *
3322 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
3323 * account, or negative errno on failure.
3324 *
3325 * This function is to be called from contexts that can sleep.
3326 */
3327int gpiod_get_value_cansleep(const struct gpio_desc *desc)
3328{
3329 int value;
3330
3331 might_sleep_if(extra_checks);
3332 VALIDATE_DESC(desc);
3333 value = gpiod_get_raw_value_commit(desc);
3334 if (value < 0)
3335 return value;
3336
3337 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3338 value = !value;
3339
3340 return value;
3341}
3342EXPORT_SYMBOL_GPL(gpiod_get_value_cansleep);
3343
3344/**
3345 * gpiod_get_raw_array_value_cansleep() - read raw values from an array of GPIOs
3346 * @array_size: number of elements in the descriptor array / value bitmap
3347 * @desc_array: array of GPIO descriptors whose values will be read
3348 * @array_info: information on applicability of fast bitmap processing path
3349 * @value_bitmap: bitmap to store the read values
3350 *
3351 * Read the raw values of the GPIOs, i.e. the values of the physical lines
3352 * without regard for their ACTIVE_LOW status. Return 0 in case of success,
3353 * else an error code.
3354 *
3355 * This function is to be called from contexts that can sleep.
3356 */
3357int gpiod_get_raw_array_value_cansleep(unsigned int array_size,
3358 struct gpio_desc **desc_array,
3359 struct gpio_array *array_info,
3360 unsigned long *value_bitmap)
3361{
3362 might_sleep_if(extra_checks);
3363 if (!desc_array)
3364 return -EINVAL;
3365 return gpiod_get_array_value_complex(true, true, array_size,
3366 desc_array, array_info,
3367 value_bitmap);
3368}
3369EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value_cansleep);
3370
3371/**
3372 * gpiod_get_array_value_cansleep() - read values from an array of GPIOs
3373 * @array_size: number of elements in the descriptor array / value bitmap
3374 * @desc_array: array of GPIO descriptors whose values will be read
3375 * @array_info: information on applicability of fast bitmap processing path
3376 * @value_bitmap: bitmap to store the read values
3377 *
3378 * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3379 * into account. Return 0 in case of success, else an error code.
3380 *
3381 * This function is to be called from contexts that can sleep.
3382 */
3383int gpiod_get_array_value_cansleep(unsigned int array_size,
3384 struct gpio_desc **desc_array,
3385 struct gpio_array *array_info,
3386 unsigned long *value_bitmap)
3387{
3388 might_sleep_if(extra_checks);
3389 if (!desc_array)
3390 return -EINVAL;
3391 return gpiod_get_array_value_complex(false, true, array_size,
3392 desc_array, array_info,
3393 value_bitmap);
3394}
3395EXPORT_SYMBOL_GPL(gpiod_get_array_value_cansleep);
3396
3397/**
3398 * gpiod_set_raw_value_cansleep() - assign a gpio's raw value
3399 * @desc: gpio whose value will be assigned
3400 * @value: value to assign
3401 *
3402 * Set the raw value of the GPIO, i.e. the value of its physical line without
3403 * regard for its ACTIVE_LOW status.
3404 *
3405 * This function is to be called from contexts that can sleep.
3406 */
3407void gpiod_set_raw_value_cansleep(struct gpio_desc *desc, int value)
3408{
3409 might_sleep_if(extra_checks);
3410 VALIDATE_DESC_VOID(desc);
3411 gpiod_set_raw_value_commit(desc, value);
3412}
3413EXPORT_SYMBOL_GPL(gpiod_set_raw_value_cansleep);
3414
3415/**
3416 * gpiod_set_value_cansleep() - assign a gpio's value
3417 * @desc: gpio whose value will be assigned
3418 * @value: value to assign
3419 *
3420 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
3421 * account
3422 *
3423 * This function is to be called from contexts that can sleep.
3424 */
3425void gpiod_set_value_cansleep(struct gpio_desc *desc, int value)
3426{
3427 might_sleep_if(extra_checks);
3428 VALIDATE_DESC_VOID(desc);
3429 gpiod_set_value_nocheck(desc, value);
3430}
3431EXPORT_SYMBOL_GPL(gpiod_set_value_cansleep);
3432
3433/**
3434 * gpiod_set_raw_array_value_cansleep() - assign values to an array of GPIOs
3435 * @array_size: number of elements in the descriptor array / value bitmap
3436 * @desc_array: array of GPIO descriptors whose values will be assigned
3437 * @array_info: information on applicability of fast bitmap processing path
3438 * @value_bitmap: bitmap of values to assign
3439 *
3440 * Set the raw values of the GPIOs, i.e. the values of the physical lines
3441 * without regard for their ACTIVE_LOW status.
3442 *
3443 * This function is to be called from contexts that can sleep.
3444 */
3445int gpiod_set_raw_array_value_cansleep(unsigned int array_size,
3446 struct gpio_desc **desc_array,
3447 struct gpio_array *array_info,
3448 unsigned long *value_bitmap)
3449{
3450 might_sleep_if(extra_checks);
3451 if (!desc_array)
3452 return -EINVAL;
3453 return gpiod_set_array_value_complex(true, true, array_size, desc_array,
3454 array_info, value_bitmap);
3455}
3456EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value_cansleep);
3457
3458/**
3459 * gpiod_add_lookup_tables() - register GPIO device consumers
3460 * @tables: list of tables of consumers to register
3461 * @n: number of tables in the list
3462 */
3463void gpiod_add_lookup_tables(struct gpiod_lookup_table **tables, size_t n)
3464{
3465 unsigned int i;
3466
3467 mutex_lock(&gpio_lookup_lock);
3468
3469 for (i = 0; i < n; i++)
3470 list_add_tail(&tables[i]->list, &gpio_lookup_list);
3471
3472 mutex_unlock(&gpio_lookup_lock);
3473}
3474
3475/**
3476 * gpiod_set_array_value_cansleep() - assign values to an array of GPIOs
3477 * @array_size: number of elements in the descriptor array / value bitmap
3478 * @desc_array: array of GPIO descriptors whose values will be assigned
3479 * @array_info: information on applicability of fast bitmap processing path
3480 * @value_bitmap: bitmap of values to assign
3481 *
3482 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3483 * into account.
3484 *
3485 * This function is to be called from contexts that can sleep.
3486 */
3487int gpiod_set_array_value_cansleep(unsigned int array_size,
3488 struct gpio_desc **desc_array,
3489 struct gpio_array *array_info,
3490 unsigned long *value_bitmap)
3491{
3492 might_sleep_if(extra_checks);
3493 if (!desc_array)
3494 return -EINVAL;
3495 return gpiod_set_array_value_complex(false, true, array_size,
3496 desc_array, array_info,
3497 value_bitmap);
3498}
3499EXPORT_SYMBOL_GPL(gpiod_set_array_value_cansleep);
3500
3501/**
3502 * gpiod_add_lookup_table() - register GPIO device consumers
3503 * @table: table of consumers to register
3504 */
3505void gpiod_add_lookup_table(struct gpiod_lookup_table *table)
3506{
3507 mutex_lock(&gpio_lookup_lock);
3508
3509 list_add_tail(&table->list, &gpio_lookup_list);
3510
3511 mutex_unlock(&gpio_lookup_lock);
3512}
3513EXPORT_SYMBOL_GPL(gpiod_add_lookup_table);
3514
3515/**
3516 * gpiod_remove_lookup_table() - unregister GPIO device consumers
3517 * @table: table of consumers to unregister
3518 */
3519void gpiod_remove_lookup_table(struct gpiod_lookup_table *table)
3520{
3521 mutex_lock(&gpio_lookup_lock);
3522
3523 list_del(&table->list);
3524
3525 mutex_unlock(&gpio_lookup_lock);
3526}
3527EXPORT_SYMBOL_GPL(gpiod_remove_lookup_table);
3528
3529/**
3530 * gpiod_add_hogs() - register a set of GPIO hogs from machine code
3531 * @hogs: table of gpio hog entries with a zeroed sentinel at the end
3532 */
3533void gpiod_add_hogs(struct gpiod_hog *hogs)
3534{
3535 struct gpio_chip *gc;
3536 struct gpiod_hog *hog;
3537
3538 mutex_lock(&gpio_machine_hogs_mutex);
3539
3540 for (hog = &hogs[0]; hog->chip_label; hog++) {
3541 list_add_tail(&hog->list, &gpio_machine_hogs);
3542
3543 /*
3544 * The chip may have been registered earlier, so check if it
3545 * exists and, if so, try to hog the line now.
3546 */
3547 gc = find_chip_by_name(hog->chip_label);
3548 if (gc)
3549 gpiochip_machine_hog(gc, hog);
3550 }
3551
3552 mutex_unlock(&gpio_machine_hogs_mutex);
3553}
3554EXPORT_SYMBOL_GPL(gpiod_add_hogs);
3555
3556static struct gpiod_lookup_table *gpiod_find_lookup_table(struct device *dev)
3557{
3558 const char *dev_id = dev ? dev_name(dev) : NULL;
3559 struct gpiod_lookup_table *table;
3560
3561 mutex_lock(&gpio_lookup_lock);
3562
3563 list_for_each_entry(table, &gpio_lookup_list, list) {
3564 if (table->dev_id && dev_id) {
3565 /*
3566 * Valid strings on both ends, must be identical to have
3567 * a match
3568 */
3569 if (!strcmp(table->dev_id, dev_id))
3570 goto found;
3571 } else {
3572 /*
3573 * One of the pointers is NULL, so both must be to have
3574 * a match
3575 */
3576 if (dev_id == table->dev_id)
3577 goto found;
3578 }
3579 }
3580 table = NULL;
3581
3582found:
3583 mutex_unlock(&gpio_lookup_lock);
3584 return table;
3585}
3586
3587static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id,
3588 unsigned int idx, unsigned long *flags)
3589{
3590 struct gpio_desc *desc = ERR_PTR(-ENOENT);
3591 struct gpiod_lookup_table *table;
3592 struct gpiod_lookup *p;
3593
3594 table = gpiod_find_lookup_table(dev);
3595 if (!table)
3596 return desc;
3597
3598 for (p = &table->table[0]; p->key; p++) {
3599 struct gpio_chip *gc;
3600
3601 /* idx must always match exactly */
3602 if (p->idx != idx)
3603 continue;
3604
3605 /* If the lookup entry has a con_id, require exact match */
3606 if (p->con_id && (!con_id || strcmp(p->con_id, con_id)))
3607 continue;
3608
3609 if (p->chip_hwnum == U16_MAX) {
3610 desc = gpio_name_to_desc(p->key);
3611 if (desc) {
3612 *flags = p->flags;
3613 return desc;
3614 }
3615
3616 dev_warn(dev, "cannot find GPIO line %s, deferring\n",
3617 p->key);
3618 return ERR_PTR(-EPROBE_DEFER);
3619 }
3620
3621 gc = find_chip_by_name(p->key);
3622
3623 if (!gc) {
3624 /*
3625 * As the lookup table indicates a chip with
3626 * p->key should exist, assume it may
3627 * still appear later and let the interested
3628 * consumer be probed again or let the Deferred
3629 * Probe infrastructure handle the error.
3630 */
3631 dev_warn(dev, "cannot find GPIO chip %s, deferring\n",
3632 p->key);
3633 return ERR_PTR(-EPROBE_DEFER);
3634 }
3635
3636 if (gc->ngpio <= p->chip_hwnum) {
3637 dev_err(dev,
3638 "requested GPIO %u (%u) is out of range [0..%u] for chip %s\n",
3639 idx, p->chip_hwnum, gc->ngpio - 1,
3640 gc->label);
3641 return ERR_PTR(-EINVAL);
3642 }
3643
3644 desc = gpiochip_get_desc(gc, p->chip_hwnum);
3645 *flags = p->flags;
3646
3647 return desc;
3648 }
3649
3650 return desc;
3651}
3652
3653static int platform_gpio_count(struct device *dev, const char *con_id)
3654{
3655 struct gpiod_lookup_table *table;
3656 struct gpiod_lookup *p;
3657 unsigned int count = 0;
3658
3659 table = gpiod_find_lookup_table(dev);
3660 if (!table)
3661 return -ENOENT;
3662
3663 for (p = &table->table[0]; p->key; p++) {
3664 if ((con_id && p->con_id && !strcmp(con_id, p->con_id)) ||
3665 (!con_id && !p->con_id))
3666 count++;
3667 }
3668 if (!count)
3669 return -ENOENT;
3670
3671 return count;
3672}
3673
3674/**
3675 * fwnode_gpiod_get_index - obtain a GPIO from firmware node
3676 * @fwnode: handle of the firmware node
3677 * @con_id: function within the GPIO consumer
3678 * @index: index of the GPIO to obtain for the consumer
3679 * @flags: GPIO initialization flags
3680 * @label: label to attach to the requested GPIO
3681 *
3682 * This function can be used for drivers that get their configuration
3683 * from opaque firmware.
3684 *
3685 * The function properly finds the corresponding GPIO using whatever is the
3686 * underlying firmware interface and then makes sure that the GPIO
3687 * descriptor is requested before it is returned to the caller.
3688 *
3689 * Returns:
3690 * On successful request the GPIO pin is configured in accordance with
3691 * provided @flags.
3692 *
3693 * In case of error an ERR_PTR() is returned.
3694 */
3695struct gpio_desc *fwnode_gpiod_get_index(struct fwnode_handle *fwnode,
3696 const char *con_id, int index,
3697 enum gpiod_flags flags,
3698 const char *label)
3699{
3700 struct gpio_desc *desc;
3701 char prop_name[32]; /* 32 is max size of property name */
3702 unsigned int i;
3703
3704 for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
3705 if (con_id)
3706 snprintf(prop_name, sizeof(prop_name), "%s-%s",
3707 con_id, gpio_suffixes[i]);
3708 else
3709 snprintf(prop_name, sizeof(prop_name), "%s",
3710 gpio_suffixes[i]);
3711
3712 desc = fwnode_get_named_gpiod(fwnode, prop_name, index, flags,
3713 label);
3714 if (!IS_ERR(desc) || (PTR_ERR(desc) != -ENOENT))
3715 break;
3716 }
3717
3718 return desc;
3719}
3720EXPORT_SYMBOL_GPL(fwnode_gpiod_get_index);
3721
3722/**
3723 * gpiod_count - return the number of GPIOs associated with a device / function
3724 * or -ENOENT if no GPIO has been assigned to the requested function
3725 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3726 * @con_id: function within the GPIO consumer
3727 */
3728int gpiod_count(struct device *dev, const char *con_id)
3729{
3730 int count = -ENOENT;
3731
3732 if (IS_ENABLED(CONFIG_OF) && dev && dev->of_node)
3733 count = of_gpio_get_count(dev, con_id);
3734 else if (IS_ENABLED(CONFIG_ACPI) && dev && ACPI_HANDLE(dev))
3735 count = acpi_gpio_count(dev, con_id);
3736
3737 if (count < 0)
3738 count = platform_gpio_count(dev, con_id);
3739
3740 return count;
3741}
3742EXPORT_SYMBOL_GPL(gpiod_count);
3743
3744/**
3745 * gpiod_get - obtain a GPIO for a given GPIO function
3746 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3747 * @con_id: function within the GPIO consumer
3748 * @flags: optional GPIO initialization flags
3749 *
3750 * Return the GPIO descriptor corresponding to the function con_id of device
3751 * dev, -ENOENT if no GPIO has been assigned to the requested function, or
3752 * another IS_ERR() code if an error occurred while trying to acquire the GPIO.
3753 */
3754struct gpio_desc *__must_check gpiod_get(struct device *dev, const char *con_id,
3755 enum gpiod_flags flags)
3756{
3757 return gpiod_get_index(dev, con_id, 0, flags);
3758}
3759EXPORT_SYMBOL_GPL(gpiod_get);
3760
3761/**
3762 * gpiod_get_optional - obtain an optional GPIO for a given GPIO function
3763 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3764 * @con_id: function within the GPIO consumer
3765 * @flags: optional GPIO initialization flags
3766 *
3767 * This is equivalent to gpiod_get(), except that when no GPIO was assigned to
3768 * the requested function it will return NULL. This is convenient for drivers
3769 * that need to handle optional GPIOs.
3770 */
3771struct gpio_desc *__must_check gpiod_get_optional(struct device *dev,
3772 const char *con_id,
3773 enum gpiod_flags flags)
3774{
3775 return gpiod_get_index_optional(dev, con_id, 0, flags);
3776}
3777EXPORT_SYMBOL_GPL(gpiod_get_optional);
3778
3779
3780/**
3781 * gpiod_configure_flags - helper function to configure a given GPIO
3782 * @desc: gpio whose value will be assigned
3783 * @con_id: function within the GPIO consumer
3784 * @lflags: bitmask of gpio_lookup_flags GPIO_* values - returned from
3785 * of_find_gpio() or of_get_gpio_hog()
3786 * @dflags: gpiod_flags - optional GPIO initialization flags
3787 *
3788 * Return 0 on success, -ENOENT if no GPIO has been assigned to the
3789 * requested function and/or index, or another IS_ERR() code if an error
3790 * occurred while trying to acquire the GPIO.
3791 */
3792int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id,
3793 unsigned long lflags, enum gpiod_flags dflags)
3794{
3795 int ret;
3796
3797 if (lflags & GPIO_ACTIVE_LOW)
3798 set_bit(FLAG_ACTIVE_LOW, &desc->flags);
3799
3800 if (lflags & GPIO_OPEN_DRAIN)
3801 set_bit(FLAG_OPEN_DRAIN, &desc->flags);
3802 else if (dflags & GPIOD_FLAGS_BIT_OPEN_DRAIN) {
3803 /*
3804 * This enforces open drain mode from the consumer side.
3805 * This is necessary for some busses like I2C, but the lookup
3806 * should *REALLY* have specified them as open drain in the
3807 * first place, so print a little warning here.
3808 */
3809 set_bit(FLAG_OPEN_DRAIN, &desc->flags);
3810 gpiod_warn(desc,
3811 "enforced open drain please flag it properly in DT/ACPI DSDT/board file\n");
3812 }
3813
3814 if (lflags & GPIO_OPEN_SOURCE)
3815 set_bit(FLAG_OPEN_SOURCE, &desc->flags);
3816
3817 if ((lflags & GPIO_PULL_UP) && (lflags & GPIO_PULL_DOWN)) {
3818 gpiod_err(desc,
3819 "both pull-up and pull-down enabled, invalid configuration\n");
3820 return -EINVAL;
3821 }
3822
3823 if (lflags & GPIO_PULL_UP)
3824 set_bit(FLAG_PULL_UP, &desc->flags);
3825 else if (lflags & GPIO_PULL_DOWN)
3826 set_bit(FLAG_PULL_DOWN, &desc->flags);
3827
3828 ret = gpiod_set_transitory(desc, (lflags & GPIO_TRANSITORY));
3829 if (ret < 0)
3830 return ret;
3831
3832 /* No particular flag request, return here... */
3833 if (!(dflags & GPIOD_FLAGS_BIT_DIR_SET)) {
3834 gpiod_dbg(desc, "no flags found for %s\n", con_id);
3835 return 0;
3836 }
3837
3838 /* Process flags */
3839 if (dflags & GPIOD_FLAGS_BIT_DIR_OUT)
3840 ret = gpiod_direction_output(desc,
3841 !!(dflags & GPIOD_FLAGS_BIT_DIR_VAL));
3842 else
3843 ret = gpiod_direction_input(desc);
3844
3845 return ret;
3846}
3847
3848/**
3849 * gpiod_get_index - obtain a GPIO from a multi-index GPIO function
3850 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3851 * @con_id: function within the GPIO consumer
3852 * @idx: index of the GPIO to obtain in the consumer
3853 * @flags: optional GPIO initialization flags
3854 *
3855 * This variant of gpiod_get() allows to access GPIOs other than the first
3856 * defined one for functions that define several GPIOs.
3857 *
3858 * Return a valid GPIO descriptor, -ENOENT if no GPIO has been assigned to the
3859 * requested function and/or index, or another IS_ERR() code if an error
3860 * occurred while trying to acquire the GPIO.
3861 */
3862struct gpio_desc *__must_check gpiod_get_index(struct device *dev,
3863 const char *con_id,
3864 unsigned int idx,
3865 enum gpiod_flags flags)
3866{
3867 unsigned long lookupflags = GPIO_LOOKUP_FLAGS_DEFAULT;
3868 struct gpio_desc *desc = NULL;
3869 int ret;
3870 /* Maybe we have a device name, maybe not */
3871 const char *devname = dev ? dev_name(dev) : "?";
3872
3873 dev_dbg(dev, "GPIO lookup for consumer %s\n", con_id);
3874
3875 if (dev) {
3876 /* Using device tree? */
3877 if (IS_ENABLED(CONFIG_OF) && dev->of_node) {
3878 dev_dbg(dev, "using device tree for GPIO lookup\n");
3879 desc = of_find_gpio(dev, con_id, idx, &lookupflags);
3880 } else if (ACPI_COMPANION(dev)) {
3881 dev_dbg(dev, "using ACPI for GPIO lookup\n");
3882 desc = acpi_find_gpio(dev, con_id, idx, &flags, &lookupflags);
3883 }
3884 }
3885
3886 /*
3887 * Either we are not using DT or ACPI, or their lookup did not return
3888 * a result. In that case, use platform lookup as a fallback.
3889 */
3890 if (!desc || desc == ERR_PTR(-ENOENT)) {
3891 dev_dbg(dev, "using lookup tables for GPIO lookup\n");
3892 desc = gpiod_find(dev, con_id, idx, &lookupflags);
3893 }
3894
3895 if (IS_ERR(desc)) {
3896 dev_dbg(dev, "No GPIO consumer %s found\n", con_id);
3897 return desc;
3898 }
3899
3900 /*
3901 * If a connection label was passed use that, else attempt to use
3902 * the device name as label
3903 */
3904 ret = gpiod_request(desc, con_id ? con_id : devname);
3905 if (ret < 0) {
3906 if (ret == -EBUSY && flags & GPIOD_FLAGS_BIT_NONEXCLUSIVE) {
3907 /*
3908 * This happens when there are several consumers for
3909 * the same GPIO line: we just return here without
3910 * further initialization. It is a bit if a hack.
3911 * This is necessary to support fixed regulators.
3912 *
3913 * FIXME: Make this more sane and safe.
3914 */
3915 dev_info(dev, "nonexclusive access to GPIO for %s\n",
3916 con_id ? con_id : devname);
3917 return desc;
3918 } else {
3919 return ERR_PTR(ret);
3920 }
3921 }
3922
3923 ret = gpiod_configure_flags(desc, con_id, lookupflags, flags);
3924 if (ret < 0) {
3925 dev_dbg(dev, "setup of GPIO %s failed\n", con_id);
3926 gpiod_put(desc);
3927 return ERR_PTR(ret);
3928 }
3929
3930 blocking_notifier_call_chain(&desc->gdev->notifier,
3931 GPIOLINE_CHANGED_REQUESTED, desc);
3932
3933 return desc;
3934}
3935EXPORT_SYMBOL_GPL(gpiod_get_index);
3936
3937/**
3938 * fwnode_get_named_gpiod - obtain a GPIO from firmware node
3939 * @fwnode: handle of the firmware node
3940 * @propname: name of the firmware property representing the GPIO
3941 * @index: index of the GPIO to obtain for the consumer
3942 * @dflags: GPIO initialization flags
3943 * @label: label to attach to the requested GPIO
3944 *
3945 * This function can be used for drivers that get their configuration
3946 * from opaque firmware.
3947 *
3948 * The function properly finds the corresponding GPIO using whatever is the
3949 * underlying firmware interface and then makes sure that the GPIO
3950 * descriptor is requested before it is returned to the caller.
3951 *
3952 * Returns:
3953 * On successful request the GPIO pin is configured in accordance with
3954 * provided @dflags.
3955 *
3956 * In case of error an ERR_PTR() is returned.
3957 */
3958struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode,
3959 const char *propname, int index,
3960 enum gpiod_flags dflags,
3961 const char *label)
3962{
3963 unsigned long lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
3964 struct gpio_desc *desc = ERR_PTR(-ENODEV);
3965 int ret;
3966
3967 if (!fwnode)
3968 return ERR_PTR(-EINVAL);
3969
3970 if (is_of_node(fwnode)) {
3971 desc = gpiod_get_from_of_node(to_of_node(fwnode),
3972 propname, index,
3973 dflags,
3974 label);
3975 return desc;
3976 } else if (is_acpi_node(fwnode)) {
3977 struct acpi_gpio_info info;
3978
3979 desc = acpi_node_get_gpiod(fwnode, propname, index, &info);
3980 if (IS_ERR(desc))
3981 return desc;
3982
3983 acpi_gpio_update_gpiod_flags(&dflags, &info);
3984 acpi_gpio_update_gpiod_lookup_flags(&lflags, &info);
3985 }
3986
3987 /* Currently only ACPI takes this path */
3988 ret = gpiod_request(desc, label);
3989 if (ret)
3990 return ERR_PTR(ret);
3991
3992 ret = gpiod_configure_flags(desc, propname, lflags, dflags);
3993 if (ret < 0) {
3994 gpiod_put(desc);
3995 return ERR_PTR(ret);
3996 }
3997
3998 blocking_notifier_call_chain(&desc->gdev->notifier,
3999 GPIOLINE_CHANGED_REQUESTED, desc);
4000
4001 return desc;
4002}
4003EXPORT_SYMBOL_GPL(fwnode_get_named_gpiod);
4004
4005/**
4006 * gpiod_get_index_optional - obtain an optional GPIO from a multi-index GPIO
4007 * function
4008 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4009 * @con_id: function within the GPIO consumer
4010 * @index: index of the GPIO to obtain in the consumer
4011 * @flags: optional GPIO initialization flags
4012 *
4013 * This is equivalent to gpiod_get_index(), except that when no GPIO with the
4014 * specified index was assigned to the requested function it will return NULL.
4015 * This is convenient for drivers that need to handle optional GPIOs.
4016 */
4017struct gpio_desc *__must_check gpiod_get_index_optional(struct device *dev,
4018 const char *con_id,
4019 unsigned int index,
4020 enum gpiod_flags flags)
4021{
4022 struct gpio_desc *desc;
4023
4024 desc = gpiod_get_index(dev, con_id, index, flags);
4025 if (IS_ERR(desc)) {
4026 if (PTR_ERR(desc) == -ENOENT)
4027 return NULL;
4028 }
4029
4030 return desc;
4031}
4032EXPORT_SYMBOL_GPL(gpiod_get_index_optional);
4033
4034/**
4035 * gpiod_hog - Hog the specified GPIO desc given the provided flags
4036 * @desc: gpio whose value will be assigned
4037 * @name: gpio line name
4038 * @lflags: bitmask of gpio_lookup_flags GPIO_* values - returned from
4039 * of_find_gpio() or of_get_gpio_hog()
4040 * @dflags: gpiod_flags - optional GPIO initialization flags
4041 */
4042int gpiod_hog(struct gpio_desc *desc, const char *name,
4043 unsigned long lflags, enum gpiod_flags dflags)
4044{
4045 struct gpio_chip *gc;
4046 struct gpio_desc *local_desc;
4047 int hwnum;
4048 int ret;
4049
4050 gc = gpiod_to_chip(desc);
4051 hwnum = gpio_chip_hwgpio(desc);
4052
4053 local_desc = gpiochip_request_own_desc(gc, hwnum, name,
4054 lflags, dflags);
4055 if (IS_ERR(local_desc)) {
4056 ret = PTR_ERR(local_desc);
4057 pr_err("requesting hog GPIO %s (chip %s, offset %d) failed, %d\n",
4058 name, gc->label, hwnum, ret);
4059 return ret;
4060 }
4061
4062 /* Mark GPIO as hogged so it can be identified and removed later */
4063 set_bit(FLAG_IS_HOGGED, &desc->flags);
4064
4065 gpiod_info(desc, "hogged as %s%s\n",
4066 (dflags & GPIOD_FLAGS_BIT_DIR_OUT) ? "output" : "input",
4067 (dflags & GPIOD_FLAGS_BIT_DIR_OUT) ?
4068 (dflags & GPIOD_FLAGS_BIT_DIR_VAL) ? "/high" : "/low" : "");
4069
4070 return 0;
4071}
4072
4073/**
4074 * gpiochip_free_hogs - Scan gpio-controller chip and release GPIO hog
4075 * @gc: gpio chip to act on
4076 */
4077static void gpiochip_free_hogs(struct gpio_chip *gc)
4078{
4079 int id;
4080
4081 for (id = 0; id < gc->ngpio; id++) {
4082 if (test_bit(FLAG_IS_HOGGED, &gc->gpiodev->descs[id].flags))
4083 gpiochip_free_own_desc(&gc->gpiodev->descs[id]);
4084 }
4085}
4086
4087/**
4088 * gpiod_get_array - obtain multiple GPIOs from a multi-index GPIO function
4089 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4090 * @con_id: function within the GPIO consumer
4091 * @flags: optional GPIO initialization flags
4092 *
4093 * This function acquires all the GPIOs defined under a given function.
4094 *
4095 * Return a struct gpio_descs containing an array of descriptors, -ENOENT if
4096 * no GPIO has been assigned to the requested function, or another IS_ERR()
4097 * code if an error occurred while trying to acquire the GPIOs.
4098 */
4099struct gpio_descs *__must_check gpiod_get_array(struct device *dev,
4100 const char *con_id,
4101 enum gpiod_flags flags)
4102{
4103 struct gpio_desc *desc;
4104 struct gpio_descs *descs;
4105 struct gpio_array *array_info = NULL;
4106 struct gpio_chip *gc;
4107 int count, bitmap_size;
4108
4109 count = gpiod_count(dev, con_id);
4110 if (count < 0)
4111 return ERR_PTR(count);
4112
4113 descs = kzalloc(struct_size(descs, desc, count), GFP_KERNEL);
4114 if (!descs)
4115 return ERR_PTR(-ENOMEM);
4116
4117 for (descs->ndescs = 0; descs->ndescs < count; ) {
4118 desc = gpiod_get_index(dev, con_id, descs->ndescs, flags);
4119 if (IS_ERR(desc)) {
4120 gpiod_put_array(descs);
4121 return ERR_CAST(desc);
4122 }
4123
4124 descs->desc[descs->ndescs] = desc;
4125
4126 gc = gpiod_to_chip(desc);
4127 /*
4128 * If pin hardware number of array member 0 is also 0, select
4129 * its chip as a candidate for fast bitmap processing path.
4130 */
4131 if (descs->ndescs == 0 && gpio_chip_hwgpio(desc) == 0) {
4132 struct gpio_descs *array;
4133
4134 bitmap_size = BITS_TO_LONGS(gc->ngpio > count ?
4135 gc->ngpio : count);
4136
4137 array = kzalloc(struct_size(descs, desc, count) +
4138 struct_size(array_info, invert_mask,
4139 3 * bitmap_size), GFP_KERNEL);
4140 if (!array) {
4141 gpiod_put_array(descs);
4142 return ERR_PTR(-ENOMEM);
4143 }
4144
4145 memcpy(array, descs,
4146 struct_size(descs, desc, descs->ndescs + 1));
4147 kfree(descs);
4148
4149 descs = array;
4150 array_info = (void *)(descs->desc + count);
4151 array_info->get_mask = array_info->invert_mask +
4152 bitmap_size;
4153 array_info->set_mask = array_info->get_mask +
4154 bitmap_size;
4155
4156 array_info->desc = descs->desc;
4157 array_info->size = count;
4158 array_info->chip = gc;
4159 bitmap_set(array_info->get_mask, descs->ndescs,
4160 count - descs->ndescs);
4161 bitmap_set(array_info->set_mask, descs->ndescs,
4162 count - descs->ndescs);
4163 descs->info = array_info;
4164 }
4165 /* Unmark array members which don't belong to the 'fast' chip */
4166 if (array_info && array_info->chip != gc) {
4167 __clear_bit(descs->ndescs, array_info->get_mask);
4168 __clear_bit(descs->ndescs, array_info->set_mask);
4169 }
4170 /*
4171 * Detect array members which belong to the 'fast' chip
4172 * but their pins are not in hardware order.
4173 */
4174 else if (array_info &&
4175 gpio_chip_hwgpio(desc) != descs->ndescs) {
4176 /*
4177 * Don't use fast path if all array members processed so
4178 * far belong to the same chip as this one but its pin
4179 * hardware number is different from its array index.
4180 */
4181 if (bitmap_full(array_info->get_mask, descs->ndescs)) {
4182 array_info = NULL;
4183 } else {
4184 __clear_bit(descs->ndescs,
4185 array_info->get_mask);
4186 __clear_bit(descs->ndescs,
4187 array_info->set_mask);
4188 }
4189 } else if (array_info) {
4190 /* Exclude open drain or open source from fast output */
4191 if (gpiochip_line_is_open_drain(gc, descs->ndescs) ||
4192 gpiochip_line_is_open_source(gc, descs->ndescs))
4193 __clear_bit(descs->ndescs,
4194 array_info->set_mask);
4195 /* Identify 'fast' pins which require invertion */
4196 if (gpiod_is_active_low(desc))
4197 __set_bit(descs->ndescs,
4198 array_info->invert_mask);
4199 }
4200
4201 descs->ndescs++;
4202 }
4203 if (array_info)
4204 dev_dbg(dev,
4205 "GPIO array info: chip=%s, size=%d, get_mask=%lx, set_mask=%lx, invert_mask=%lx\n",
4206 array_info->chip->label, array_info->size,
4207 *array_info->get_mask, *array_info->set_mask,
4208 *array_info->invert_mask);
4209 return descs;
4210}
4211EXPORT_SYMBOL_GPL(gpiod_get_array);
4212
4213/**
4214 * gpiod_get_array_optional - obtain multiple GPIOs from a multi-index GPIO
4215 * function
4216 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4217 * @con_id: function within the GPIO consumer
4218 * @flags: optional GPIO initialization flags
4219 *
4220 * This is equivalent to gpiod_get_array(), except that when no GPIO was
4221 * assigned to the requested function it will return NULL.
4222 */
4223struct gpio_descs *__must_check gpiod_get_array_optional(struct device *dev,
4224 const char *con_id,
4225 enum gpiod_flags flags)
4226{
4227 struct gpio_descs *descs;
4228
4229 descs = gpiod_get_array(dev, con_id, flags);
4230 if (PTR_ERR(descs) == -ENOENT)
4231 return NULL;
4232
4233 return descs;
4234}
4235EXPORT_SYMBOL_GPL(gpiod_get_array_optional);
4236
4237/**
4238 * gpiod_put - dispose of a GPIO descriptor
4239 * @desc: GPIO descriptor to dispose of
4240 *
4241 * No descriptor can be used after gpiod_put() has been called on it.
4242 */
4243void gpiod_put(struct gpio_desc *desc)
4244{
4245 if (desc)
4246 gpiod_free(desc);
4247}
4248EXPORT_SYMBOL_GPL(gpiod_put);
4249
4250/**
4251 * gpiod_put_array - dispose of multiple GPIO descriptors
4252 * @descs: struct gpio_descs containing an array of descriptors
4253 */
4254void gpiod_put_array(struct gpio_descs *descs)
4255{
4256 unsigned int i;
4257
4258 for (i = 0; i < descs->ndescs; i++)
4259 gpiod_put(descs->desc[i]);
4260
4261 kfree(descs);
4262}
4263EXPORT_SYMBOL_GPL(gpiod_put_array);
4264
4265static int __init gpiolib_dev_init(void)
4266{
4267 int ret;
4268
4269 /* Register GPIO sysfs bus */
4270 ret = bus_register(&gpio_bus_type);
4271 if (ret < 0) {
4272 pr_err("gpiolib: could not register GPIO bus type\n");
4273 return ret;
4274 }
4275
4276 ret = alloc_chrdev_region(&gpio_devt, 0, GPIO_DEV_MAX, GPIOCHIP_NAME);
4277 if (ret < 0) {
4278 pr_err("gpiolib: failed to allocate char dev region\n");
4279 bus_unregister(&gpio_bus_type);
4280 return ret;
4281 }
4282
4283 gpiolib_initialized = true;
4284 gpiochip_setup_devs();
4285
4286#if IS_ENABLED(CONFIG_OF_DYNAMIC) && IS_ENABLED(CONFIG_OF_GPIO)
4287 WARN_ON(of_reconfig_notifier_register(&gpio_of_notifier));
4288#endif /* CONFIG_OF_DYNAMIC && CONFIG_OF_GPIO */
4289
4290 return ret;
4291}
4292core_initcall(gpiolib_dev_init);
4293
4294#ifdef CONFIG_DEBUG_FS
4295
4296static void gpiolib_dbg_show(struct seq_file *s, struct gpio_device *gdev)
4297{
4298 unsigned i;
4299 struct gpio_chip *gc = gdev->chip;
4300 unsigned gpio = gdev->base;
4301 struct gpio_desc *gdesc = &gdev->descs[0];
4302 bool is_out;
4303 bool is_irq;
4304 bool active_low;
4305
4306 for (i = 0; i < gdev->ngpio; i++, gpio++, gdesc++) {
4307 if (!test_bit(FLAG_REQUESTED, &gdesc->flags)) {
4308 if (gdesc->name) {
4309 seq_printf(s, " gpio-%-3d (%-20.20s)\n",
4310 gpio, gdesc->name);
4311 }
4312 continue;
4313 }
4314
4315 gpiod_get_direction(gdesc);
4316 is_out = test_bit(FLAG_IS_OUT, &gdesc->flags);
4317 is_irq = test_bit(FLAG_USED_AS_IRQ, &gdesc->flags);
4318 active_low = test_bit(FLAG_ACTIVE_LOW, &gdesc->flags);
4319 seq_printf(s, " gpio-%-3d (%-20.20s|%-20.20s) %s %s %s%s",
4320 gpio, gdesc->name ? gdesc->name : "", gdesc->label,
4321 is_out ? "out" : "in ",
4322 gc->get ? (gc->get(gc, i) ? "hi" : "lo") : "? ",
4323 is_irq ? "IRQ " : "",
4324 active_low ? "ACTIVE LOW" : "");
4325 seq_printf(s, "\n");
4326 }
4327}
4328
4329static void *gpiolib_seq_start(struct seq_file *s, loff_t *pos)
4330{
4331 unsigned long flags;
4332 struct gpio_device *gdev = NULL;
4333 loff_t index = *pos;
4334
4335 s->private = "";
4336
4337 spin_lock_irqsave(&gpio_lock, flags);
4338 list_for_each_entry(gdev, &gpio_devices, list)
4339 if (index-- == 0) {
4340 spin_unlock_irqrestore(&gpio_lock, flags);
4341 return gdev;
4342 }
4343 spin_unlock_irqrestore(&gpio_lock, flags);
4344
4345 return NULL;
4346}
4347
4348static void *gpiolib_seq_next(struct seq_file *s, void *v, loff_t *pos)
4349{
4350 unsigned long flags;
4351 struct gpio_device *gdev = v;
4352 void *ret = NULL;
4353
4354 spin_lock_irqsave(&gpio_lock, flags);
4355 if (list_is_last(&gdev->list, &gpio_devices))
4356 ret = NULL;
4357 else
4358 ret = list_entry(gdev->list.next, struct gpio_device, list);
4359 spin_unlock_irqrestore(&gpio_lock, flags);
4360
4361 s->private = "\n";
4362 ++*pos;
4363
4364 return ret;
4365}
4366
4367static void gpiolib_seq_stop(struct seq_file *s, void *v)
4368{
4369}
4370
4371static int gpiolib_seq_show(struct seq_file *s, void *v)
4372{
4373 struct gpio_device *gdev = v;
4374 struct gpio_chip *gc = gdev->chip;
4375 struct device *parent;
4376
4377 if (!gc) {
4378 seq_printf(s, "%s%s: (dangling chip)", (char *)s->private,
4379 dev_name(&gdev->dev));
4380 return 0;
4381 }
4382
4383 seq_printf(s, "%s%s: GPIOs %d-%d", (char *)s->private,
4384 dev_name(&gdev->dev),
4385 gdev->base, gdev->base + gdev->ngpio - 1);
4386 parent = gc->parent;
4387 if (parent)
4388 seq_printf(s, ", parent: %s/%s",
4389 parent->bus ? parent->bus->name : "no-bus",
4390 dev_name(parent));
4391 if (gc->label)
4392 seq_printf(s, ", %s", gc->label);
4393 if (gc->can_sleep)
4394 seq_printf(s, ", can sleep");
4395 seq_printf(s, ":\n");
4396
4397 if (gc->dbg_show)
4398 gc->dbg_show(s, gc);
4399 else
4400 gpiolib_dbg_show(s, gdev);
4401
4402 return 0;
4403}
4404
4405static const struct seq_operations gpiolib_seq_ops = {
4406 .start = gpiolib_seq_start,
4407 .next = gpiolib_seq_next,
4408 .stop = gpiolib_seq_stop,
4409 .show = gpiolib_seq_show,
4410};
4411
4412static int gpiolib_open(struct inode *inode, struct file *file)
4413{
4414 return seq_open(file, &gpiolib_seq_ops);
4415}
4416
4417static const struct file_operations gpiolib_operations = {
4418 .owner = THIS_MODULE,
4419 .open = gpiolib_open,
4420 .read = seq_read,
4421 .llseek = seq_lseek,
4422 .release = seq_release,
4423};
4424
4425static int __init gpiolib_debugfs_init(void)
4426{
4427 /* /sys/kernel/debug/gpio */
4428 debugfs_create_file("gpio", S_IFREG | S_IRUGO, NULL, NULL,
4429 &gpiolib_operations);
4430 return 0;
4431}
4432subsys_initcall(gpiolib_debugfs_init);
4433
4434#endif /* DEBUG_FS */
1#include <linux/bitmap.h>
2#include <linux/kernel.h>
3#include <linux/module.h>
4#include <linux/interrupt.h>
5#include <linux/irq.h>
6#include <linux/spinlock.h>
7#include <linux/list.h>
8#include <linux/device.h>
9#include <linux/err.h>
10#include <linux/debugfs.h>
11#include <linux/seq_file.h>
12#include <linux/gpio.h>
13#include <linux/of_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
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 struct bus_type gpio_bus_type = {
61 .name = "gpio",
62};
63
64/* gpio_lock prevents conflicts during gpio_desc[] table updates.
65 * While any GPIO is requested, its gpio_chip is not removable;
66 * each GPIO's "requested" flag serves as a lock and refcount.
67 */
68DEFINE_SPINLOCK(gpio_lock);
69
70static DEFINE_MUTEX(gpio_lookup_lock);
71static LIST_HEAD(gpio_lookup_list);
72LIST_HEAD(gpio_devices);
73
74static void gpiochip_free_hogs(struct gpio_chip *chip);
75static int gpiochip_add_irqchip(struct gpio_chip *gpiochip,
76 struct lock_class_key *lock_key,
77 struct lock_class_key *request_key);
78static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip);
79static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gpiochip);
80static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gpiochip);
81
82static bool gpiolib_initialized;
83
84static inline void desc_set_label(struct gpio_desc *d, const char *label)
85{
86 d->label = label;
87}
88
89/**
90 * gpio_to_desc - Convert a GPIO number to its descriptor
91 * @gpio: global GPIO number
92 *
93 * Returns:
94 * The GPIO descriptor associated with the given GPIO, or %NULL if no GPIO
95 * with the given number exists in the system.
96 */
97struct gpio_desc *gpio_to_desc(unsigned gpio)
98{
99 struct gpio_device *gdev;
100 unsigned long flags;
101
102 spin_lock_irqsave(&gpio_lock, flags);
103
104 list_for_each_entry(gdev, &gpio_devices, list) {
105 if (gdev->base <= gpio &&
106 gdev->base + gdev->ngpio > gpio) {
107 spin_unlock_irqrestore(&gpio_lock, flags);
108 return &gdev->descs[gpio - gdev->base];
109 }
110 }
111
112 spin_unlock_irqrestore(&gpio_lock, flags);
113
114 if (!gpio_is_valid(gpio))
115 WARN(1, "invalid GPIO %d\n", gpio);
116
117 return NULL;
118}
119EXPORT_SYMBOL_GPL(gpio_to_desc);
120
121/**
122 * gpiochip_get_desc - get the GPIO descriptor corresponding to the given
123 * hardware number for this chip
124 * @chip: GPIO chip
125 * @hwnum: hardware number of the GPIO for this chip
126 *
127 * Returns:
128 * A pointer to the GPIO descriptor or %ERR_PTR(-EINVAL) if no GPIO exists
129 * in the given chip for the specified hardware number.
130 */
131struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip,
132 u16 hwnum)
133{
134 struct gpio_device *gdev = chip->gpiodev;
135
136 if (hwnum >= gdev->ngpio)
137 return ERR_PTR(-EINVAL);
138
139 return &gdev->descs[hwnum];
140}
141
142/**
143 * desc_to_gpio - convert a GPIO descriptor to the integer namespace
144 * @desc: GPIO descriptor
145 *
146 * This should disappear in the future but is needed since we still
147 * use GPIO numbers for error messages and sysfs nodes.
148 *
149 * Returns:
150 * The global GPIO number for the GPIO specified by its descriptor.
151 */
152int desc_to_gpio(const struct gpio_desc *desc)
153{
154 return desc->gdev->base + (desc - &desc->gdev->descs[0]);
155}
156EXPORT_SYMBOL_GPL(desc_to_gpio);
157
158
159/**
160 * gpiod_to_chip - Return the GPIO chip to which a GPIO descriptor belongs
161 * @desc: descriptor to return the chip of
162 */
163struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc)
164{
165 if (!desc || !desc->gdev)
166 return NULL;
167 return desc->gdev->chip;
168}
169EXPORT_SYMBOL_GPL(gpiod_to_chip);
170
171/* dynamic allocation of GPIOs, e.g. on a hotplugged device */
172static int gpiochip_find_base(int ngpio)
173{
174 struct gpio_device *gdev;
175 int base = ARCH_NR_GPIOS - ngpio;
176
177 list_for_each_entry_reverse(gdev, &gpio_devices, list) {
178 /* found a free space? */
179 if (gdev->base + gdev->ngpio <= base)
180 break;
181 else
182 /* nope, check the space right before the chip */
183 base = gdev->base - ngpio;
184 }
185
186 if (gpio_is_valid(base)) {
187 pr_debug("%s: found new base at %d\n", __func__, base);
188 return base;
189 } else {
190 pr_err("%s: cannot find free range\n", __func__);
191 return -ENOSPC;
192 }
193}
194
195/**
196 * gpiod_get_direction - return the current direction of a GPIO
197 * @desc: GPIO to get the direction of
198 *
199 * Returns 0 for output, 1 for input, or an error code in case of error.
200 *
201 * This function may sleep if gpiod_cansleep() is true.
202 */
203int gpiod_get_direction(struct gpio_desc *desc)
204{
205 struct gpio_chip *chip;
206 unsigned offset;
207 int status = -EINVAL;
208
209 chip = gpiod_to_chip(desc);
210 offset = gpio_chip_hwgpio(desc);
211
212 if (!chip->get_direction)
213 return status;
214
215 status = chip->get_direction(chip, offset);
216 if (status > 0) {
217 /* GPIOF_DIR_IN, or other positive */
218 status = 1;
219 clear_bit(FLAG_IS_OUT, &desc->flags);
220 }
221 if (status == 0) {
222 /* GPIOF_DIR_OUT */
223 set_bit(FLAG_IS_OUT, &desc->flags);
224 }
225 return status;
226}
227EXPORT_SYMBOL_GPL(gpiod_get_direction);
228
229/*
230 * Add a new chip to the global chips list, keeping the list of chips sorted
231 * by range(means [base, base + ngpio - 1]) order.
232 *
233 * Return -EBUSY if the new chip overlaps with some other chip's integer
234 * space.
235 */
236static int gpiodev_add_to_list(struct gpio_device *gdev)
237{
238 struct gpio_device *prev, *next;
239
240 if (list_empty(&gpio_devices)) {
241 /* initial entry in list */
242 list_add_tail(&gdev->list, &gpio_devices);
243 return 0;
244 }
245
246 next = list_entry(gpio_devices.next, struct gpio_device, list);
247 if (gdev->base + gdev->ngpio <= next->base) {
248 /* add before first entry */
249 list_add(&gdev->list, &gpio_devices);
250 return 0;
251 }
252
253 prev = list_entry(gpio_devices.prev, struct gpio_device, list);
254 if (prev->base + prev->ngpio <= gdev->base) {
255 /* add behind last entry */
256 list_add_tail(&gdev->list, &gpio_devices);
257 return 0;
258 }
259
260 list_for_each_entry_safe(prev, next, &gpio_devices, list) {
261 /* at the end of the list */
262 if (&next->list == &gpio_devices)
263 break;
264
265 /* add between prev and next */
266 if (prev->base + prev->ngpio <= gdev->base
267 && gdev->base + gdev->ngpio <= next->base) {
268 list_add(&gdev->list, &prev->list);
269 return 0;
270 }
271 }
272
273 dev_err(&gdev->dev, "GPIO integer space overlap, cannot add chip\n");
274 return -EBUSY;
275}
276
277/*
278 * Convert a GPIO name to its descriptor
279 */
280static struct gpio_desc *gpio_name_to_desc(const char * const name)
281{
282 struct gpio_device *gdev;
283 unsigned long flags;
284
285 spin_lock_irqsave(&gpio_lock, flags);
286
287 list_for_each_entry(gdev, &gpio_devices, list) {
288 int i;
289
290 for (i = 0; i != gdev->ngpio; ++i) {
291 struct gpio_desc *desc = &gdev->descs[i];
292
293 if (!desc->name || !name)
294 continue;
295
296 if (!strcmp(desc->name, name)) {
297 spin_unlock_irqrestore(&gpio_lock, flags);
298 return desc;
299 }
300 }
301 }
302
303 spin_unlock_irqrestore(&gpio_lock, flags);
304
305 return NULL;
306}
307
308/*
309 * Takes the names from gc->names and checks if they are all unique. If they
310 * are, they are assigned to their gpio descriptors.
311 *
312 * Warning if one of the names is already used for a different GPIO.
313 */
314static int gpiochip_set_desc_names(struct gpio_chip *gc)
315{
316 struct gpio_device *gdev = gc->gpiodev;
317 int i;
318
319 if (!gc->names)
320 return 0;
321
322 /* First check all names if they are unique */
323 for (i = 0; i != gc->ngpio; ++i) {
324 struct gpio_desc *gpio;
325
326 gpio = gpio_name_to_desc(gc->names[i]);
327 if (gpio)
328 dev_warn(&gdev->dev,
329 "Detected name collision for GPIO name '%s'\n",
330 gc->names[i]);
331 }
332
333 /* Then add all names to the GPIO descriptors */
334 for (i = 0; i != gc->ngpio; ++i)
335 gdev->descs[i].name = gc->names[i];
336
337 return 0;
338}
339
340static unsigned long *gpiochip_allocate_mask(struct gpio_chip *chip)
341{
342 unsigned long *p;
343
344 p = kmalloc_array(BITS_TO_LONGS(chip->ngpio), sizeof(*p), GFP_KERNEL);
345 if (!p)
346 return NULL;
347
348 /* Assume by default all GPIOs are valid */
349 bitmap_fill(p, chip->ngpio);
350
351 return p;
352}
353
354static int gpiochip_init_valid_mask(struct gpio_chip *gpiochip)
355{
356#ifdef CONFIG_OF_GPIO
357 int size;
358 struct device_node *np = gpiochip->of_node;
359
360 size = of_property_count_u32_elems(np, "gpio-reserved-ranges");
361 if (size > 0 && size % 2 == 0)
362 gpiochip->need_valid_mask = true;
363#endif
364
365 if (!gpiochip->need_valid_mask)
366 return 0;
367
368 gpiochip->valid_mask = gpiochip_allocate_mask(gpiochip);
369 if (!gpiochip->valid_mask)
370 return -ENOMEM;
371
372 return 0;
373}
374
375static void gpiochip_free_valid_mask(struct gpio_chip *gpiochip)
376{
377 kfree(gpiochip->valid_mask);
378 gpiochip->valid_mask = NULL;
379}
380
381bool gpiochip_line_is_valid(const struct gpio_chip *gpiochip,
382 unsigned int offset)
383{
384 /* No mask means all valid */
385 if (likely(!gpiochip->valid_mask))
386 return true;
387 return test_bit(offset, gpiochip->valid_mask);
388}
389EXPORT_SYMBOL_GPL(gpiochip_line_is_valid);
390
391/*
392 * GPIO line handle management
393 */
394
395/**
396 * struct linehandle_state - contains the state of a userspace handle
397 * @gdev: the GPIO device the handle pertains to
398 * @label: consumer label used to tag descriptors
399 * @descs: the GPIO descriptors held by this handle
400 * @numdescs: the number of descriptors held in the descs array
401 */
402struct linehandle_state {
403 struct gpio_device *gdev;
404 const char *label;
405 struct gpio_desc *descs[GPIOHANDLES_MAX];
406 u32 numdescs;
407};
408
409#define GPIOHANDLE_REQUEST_VALID_FLAGS \
410 (GPIOHANDLE_REQUEST_INPUT | \
411 GPIOHANDLE_REQUEST_OUTPUT | \
412 GPIOHANDLE_REQUEST_ACTIVE_LOW | \
413 GPIOHANDLE_REQUEST_OPEN_DRAIN | \
414 GPIOHANDLE_REQUEST_OPEN_SOURCE)
415
416static long linehandle_ioctl(struct file *filep, unsigned int cmd,
417 unsigned long arg)
418{
419 struct linehandle_state *lh = filep->private_data;
420 void __user *ip = (void __user *)arg;
421 struct gpiohandle_data ghd;
422 int vals[GPIOHANDLES_MAX];
423 int i;
424
425 if (cmd == GPIOHANDLE_GET_LINE_VALUES_IOCTL) {
426 /* TODO: check if descriptors are really input */
427 int ret = gpiod_get_array_value_complex(false,
428 true,
429 lh->numdescs,
430 lh->descs,
431 vals);
432 if (ret)
433 return ret;
434
435 memset(&ghd, 0, sizeof(ghd));
436 for (i = 0; i < lh->numdescs; i++)
437 ghd.values[i] = vals[i];
438
439 if (copy_to_user(ip, &ghd, sizeof(ghd)))
440 return -EFAULT;
441
442 return 0;
443 } else if (cmd == GPIOHANDLE_SET_LINE_VALUES_IOCTL) {
444 /* TODO: check if descriptors are really output */
445 if (copy_from_user(&ghd, ip, sizeof(ghd)))
446 return -EFAULT;
447
448 /* Clamp all values to [0,1] */
449 for (i = 0; i < lh->numdescs; i++)
450 vals[i] = !!ghd.values[i];
451
452 /* Reuse the array setting function */
453 gpiod_set_array_value_complex(false,
454 true,
455 lh->numdescs,
456 lh->descs,
457 vals);
458 return 0;
459 }
460 return -EINVAL;
461}
462
463#ifdef CONFIG_COMPAT
464static long linehandle_ioctl_compat(struct file *filep, unsigned int cmd,
465 unsigned long arg)
466{
467 return linehandle_ioctl(filep, cmd, (unsigned long)compat_ptr(arg));
468}
469#endif
470
471static int linehandle_release(struct inode *inode, struct file *filep)
472{
473 struct linehandle_state *lh = filep->private_data;
474 struct gpio_device *gdev = lh->gdev;
475 int i;
476
477 for (i = 0; i < lh->numdescs; i++)
478 gpiod_free(lh->descs[i]);
479 kfree(lh->label);
480 kfree(lh);
481 put_device(&gdev->dev);
482 return 0;
483}
484
485static const struct file_operations linehandle_fileops = {
486 .release = linehandle_release,
487 .owner = THIS_MODULE,
488 .llseek = noop_llseek,
489 .unlocked_ioctl = linehandle_ioctl,
490#ifdef CONFIG_COMPAT
491 .compat_ioctl = linehandle_ioctl_compat,
492#endif
493};
494
495static int linehandle_create(struct gpio_device *gdev, void __user *ip)
496{
497 struct gpiohandle_request handlereq;
498 struct linehandle_state *lh;
499 struct file *file;
500 int fd, i, count = 0, ret;
501 u32 lflags;
502
503 if (copy_from_user(&handlereq, ip, sizeof(handlereq)))
504 return -EFAULT;
505 if ((handlereq.lines == 0) || (handlereq.lines > GPIOHANDLES_MAX))
506 return -EINVAL;
507
508 lflags = handlereq.flags;
509
510 /* Return an error if an unknown flag is set */
511 if (lflags & ~GPIOHANDLE_REQUEST_VALID_FLAGS)
512 return -EINVAL;
513
514 /*
515 * Do not allow OPEN_SOURCE & OPEN_DRAIN flags in a single request. If
516 * the hardware actually supports enabling both at the same time the
517 * electrical result would be disastrous.
518 */
519 if ((lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN) &&
520 (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE))
521 return -EINVAL;
522
523 /* OPEN_DRAIN and OPEN_SOURCE flags only make sense for output mode. */
524 if (!(lflags & GPIOHANDLE_REQUEST_OUTPUT) &&
525 ((lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN) ||
526 (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE)))
527 return -EINVAL;
528
529 lh = kzalloc(sizeof(*lh), GFP_KERNEL);
530 if (!lh)
531 return -ENOMEM;
532 lh->gdev = gdev;
533 get_device(&gdev->dev);
534
535 /* Make sure this is terminated */
536 handlereq.consumer_label[sizeof(handlereq.consumer_label)-1] = '\0';
537 if (strlen(handlereq.consumer_label)) {
538 lh->label = kstrdup(handlereq.consumer_label,
539 GFP_KERNEL);
540 if (!lh->label) {
541 ret = -ENOMEM;
542 goto out_free_lh;
543 }
544 }
545
546 /* Request each GPIO */
547 for (i = 0; i < handlereq.lines; i++) {
548 u32 offset = handlereq.lineoffsets[i];
549 struct gpio_desc *desc;
550
551 if (offset >= gdev->ngpio) {
552 ret = -EINVAL;
553 goto out_free_descs;
554 }
555
556 desc = &gdev->descs[offset];
557 ret = gpiod_request(desc, lh->label);
558 if (ret)
559 goto out_free_descs;
560 lh->descs[i] = desc;
561 count = i;
562
563 if (lflags & GPIOHANDLE_REQUEST_ACTIVE_LOW)
564 set_bit(FLAG_ACTIVE_LOW, &desc->flags);
565 if (lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN)
566 set_bit(FLAG_OPEN_DRAIN, &desc->flags);
567 if (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE)
568 set_bit(FLAG_OPEN_SOURCE, &desc->flags);
569
570 ret = gpiod_set_transitory(desc, false);
571 if (ret < 0)
572 goto out_free_descs;
573
574 /*
575 * Lines have to be requested explicitly for input
576 * or output, else the line will be treated "as is".
577 */
578 if (lflags & GPIOHANDLE_REQUEST_OUTPUT) {
579 int val = !!handlereq.default_values[i];
580
581 ret = gpiod_direction_output(desc, val);
582 if (ret)
583 goto out_free_descs;
584 } else if (lflags & GPIOHANDLE_REQUEST_INPUT) {
585 ret = gpiod_direction_input(desc);
586 if (ret)
587 goto out_free_descs;
588 }
589 dev_dbg(&gdev->dev, "registered chardev handle for line %d\n",
590 offset);
591 }
592 /* Let i point at the last handle */
593 i--;
594 lh->numdescs = handlereq.lines;
595
596 fd = get_unused_fd_flags(O_RDONLY | O_CLOEXEC);
597 if (fd < 0) {
598 ret = fd;
599 goto out_free_descs;
600 }
601
602 file = anon_inode_getfile("gpio-linehandle",
603 &linehandle_fileops,
604 lh,
605 O_RDONLY | O_CLOEXEC);
606 if (IS_ERR(file)) {
607 ret = PTR_ERR(file);
608 goto out_put_unused_fd;
609 }
610
611 handlereq.fd = fd;
612 if (copy_to_user(ip, &handlereq, sizeof(handlereq))) {
613 /*
614 * fput() will trigger the release() callback, so do not go onto
615 * the regular error cleanup path here.
616 */
617 fput(file);
618 put_unused_fd(fd);
619 return -EFAULT;
620 }
621
622 fd_install(fd, file);
623
624 dev_dbg(&gdev->dev, "registered chardev handle for %d lines\n",
625 lh->numdescs);
626
627 return 0;
628
629out_put_unused_fd:
630 put_unused_fd(fd);
631out_free_descs:
632 for (i = 0; i < count; i++)
633 gpiod_free(lh->descs[i]);
634 kfree(lh->label);
635out_free_lh:
636 kfree(lh);
637 put_device(&gdev->dev);
638 return ret;
639}
640
641/*
642 * GPIO line event management
643 */
644
645/**
646 * struct lineevent_state - contains the state of a userspace event
647 * @gdev: the GPIO device the event pertains to
648 * @label: consumer label used to tag descriptors
649 * @desc: the GPIO descriptor held by this event
650 * @eflags: the event flags this line was requested with
651 * @irq: the interrupt that trigger in response to events on this GPIO
652 * @wait: wait queue that handles blocking reads of events
653 * @events: KFIFO for the GPIO events
654 * @read_lock: mutex lock to protect reads from colliding with adding
655 * new events to the FIFO
656 * @timestamp: cache for the timestamp storing it between hardirq
657 * and IRQ thread, used to bring the timestamp close to the actual
658 * event
659 */
660struct lineevent_state {
661 struct gpio_device *gdev;
662 const char *label;
663 struct gpio_desc *desc;
664 u32 eflags;
665 int irq;
666 wait_queue_head_t wait;
667 DECLARE_KFIFO(events, struct gpioevent_data, 16);
668 struct mutex read_lock;
669 u64 timestamp;
670};
671
672#define GPIOEVENT_REQUEST_VALID_FLAGS \
673 (GPIOEVENT_REQUEST_RISING_EDGE | \
674 GPIOEVENT_REQUEST_FALLING_EDGE)
675
676static __poll_t lineevent_poll(struct file *filep,
677 struct poll_table_struct *wait)
678{
679 struct lineevent_state *le = filep->private_data;
680 __poll_t events = 0;
681
682 poll_wait(filep, &le->wait, wait);
683
684 if (!kfifo_is_empty(&le->events))
685 events = EPOLLIN | EPOLLRDNORM;
686
687 return events;
688}
689
690
691static ssize_t lineevent_read(struct file *filep,
692 char __user *buf,
693 size_t count,
694 loff_t *f_ps)
695{
696 struct lineevent_state *le = filep->private_data;
697 unsigned int copied;
698 int ret;
699
700 if (count < sizeof(struct gpioevent_data))
701 return -EINVAL;
702
703 do {
704 if (kfifo_is_empty(&le->events)) {
705 if (filep->f_flags & O_NONBLOCK)
706 return -EAGAIN;
707
708 ret = wait_event_interruptible(le->wait,
709 !kfifo_is_empty(&le->events));
710 if (ret)
711 return ret;
712 }
713
714 if (mutex_lock_interruptible(&le->read_lock))
715 return -ERESTARTSYS;
716 ret = kfifo_to_user(&le->events, buf, count, &copied);
717 mutex_unlock(&le->read_lock);
718
719 if (ret)
720 return ret;
721
722 /*
723 * If we couldn't read anything from the fifo (a different
724 * thread might have been faster) we either return -EAGAIN if
725 * the file descriptor is non-blocking, otherwise we go back to
726 * sleep and wait for more data to arrive.
727 */
728 if (copied == 0 && (filep->f_flags & O_NONBLOCK))
729 return -EAGAIN;
730
731 } while (copied == 0);
732
733 return copied;
734}
735
736static int lineevent_release(struct inode *inode, struct file *filep)
737{
738 struct lineevent_state *le = filep->private_data;
739 struct gpio_device *gdev = le->gdev;
740
741 free_irq(le->irq, le);
742 gpiod_free(le->desc);
743 kfree(le->label);
744 kfree(le);
745 put_device(&gdev->dev);
746 return 0;
747}
748
749static long lineevent_ioctl(struct file *filep, unsigned int cmd,
750 unsigned long arg)
751{
752 struct lineevent_state *le = filep->private_data;
753 void __user *ip = (void __user *)arg;
754 struct gpiohandle_data ghd;
755
756 /*
757 * We can get the value for an event line but not set it,
758 * because it is input by definition.
759 */
760 if (cmd == GPIOHANDLE_GET_LINE_VALUES_IOCTL) {
761 int val;
762
763 memset(&ghd, 0, sizeof(ghd));
764
765 val = gpiod_get_value_cansleep(le->desc);
766 if (val < 0)
767 return val;
768 ghd.values[0] = val;
769
770 if (copy_to_user(ip, &ghd, sizeof(ghd)))
771 return -EFAULT;
772
773 return 0;
774 }
775 return -EINVAL;
776}
777
778#ifdef CONFIG_COMPAT
779static long lineevent_ioctl_compat(struct file *filep, unsigned int cmd,
780 unsigned long arg)
781{
782 return lineevent_ioctl(filep, cmd, (unsigned long)compat_ptr(arg));
783}
784#endif
785
786static const struct file_operations lineevent_fileops = {
787 .release = lineevent_release,
788 .read = lineevent_read,
789 .poll = lineevent_poll,
790 .owner = THIS_MODULE,
791 .llseek = noop_llseek,
792 .unlocked_ioctl = lineevent_ioctl,
793#ifdef CONFIG_COMPAT
794 .compat_ioctl = lineevent_ioctl_compat,
795#endif
796};
797
798static irqreturn_t lineevent_irq_thread(int irq, void *p)
799{
800 struct lineevent_state *le = p;
801 struct gpioevent_data ge;
802 int ret, level;
803
804 /* Do not leak kernel stack to userspace */
805 memset(&ge, 0, sizeof(ge));
806
807 ge.timestamp = le->timestamp;
808 level = gpiod_get_value_cansleep(le->desc);
809
810 if (le->eflags & GPIOEVENT_REQUEST_RISING_EDGE
811 && le->eflags & GPIOEVENT_REQUEST_FALLING_EDGE) {
812 if (level)
813 /* Emit low-to-high event */
814 ge.id = GPIOEVENT_EVENT_RISING_EDGE;
815 else
816 /* Emit high-to-low event */
817 ge.id = GPIOEVENT_EVENT_FALLING_EDGE;
818 } else if (le->eflags & GPIOEVENT_REQUEST_RISING_EDGE && level) {
819 /* Emit low-to-high event */
820 ge.id = GPIOEVENT_EVENT_RISING_EDGE;
821 } else if (le->eflags & GPIOEVENT_REQUEST_FALLING_EDGE && !level) {
822 /* Emit high-to-low event */
823 ge.id = GPIOEVENT_EVENT_FALLING_EDGE;
824 } else {
825 return IRQ_NONE;
826 }
827
828 ret = kfifo_put(&le->events, ge);
829 if (ret != 0)
830 wake_up_poll(&le->wait, EPOLLIN);
831
832 return IRQ_HANDLED;
833}
834
835static irqreturn_t lineevent_irq_handler(int irq, void *p)
836{
837 struct lineevent_state *le = p;
838
839 /*
840 * Just store the timestamp in hardirq context so we get it as
841 * close in time as possible to the actual event.
842 */
843 le->timestamp = ktime_get_real_ns();
844
845 return IRQ_WAKE_THREAD;
846}
847
848static int lineevent_create(struct gpio_device *gdev, void __user *ip)
849{
850 struct gpioevent_request eventreq;
851 struct lineevent_state *le;
852 struct gpio_desc *desc;
853 struct file *file;
854 u32 offset;
855 u32 lflags;
856 u32 eflags;
857 int fd;
858 int ret;
859 int irqflags = 0;
860
861 if (copy_from_user(&eventreq, ip, sizeof(eventreq)))
862 return -EFAULT;
863
864 le = kzalloc(sizeof(*le), GFP_KERNEL);
865 if (!le)
866 return -ENOMEM;
867 le->gdev = gdev;
868 get_device(&gdev->dev);
869
870 /* Make sure this is terminated */
871 eventreq.consumer_label[sizeof(eventreq.consumer_label)-1] = '\0';
872 if (strlen(eventreq.consumer_label)) {
873 le->label = kstrdup(eventreq.consumer_label,
874 GFP_KERNEL);
875 if (!le->label) {
876 ret = -ENOMEM;
877 goto out_free_le;
878 }
879 }
880
881 offset = eventreq.lineoffset;
882 lflags = eventreq.handleflags;
883 eflags = eventreq.eventflags;
884
885 if (offset >= gdev->ngpio) {
886 ret = -EINVAL;
887 goto out_free_label;
888 }
889
890 /* Return an error if a unknown flag is set */
891 if ((lflags & ~GPIOHANDLE_REQUEST_VALID_FLAGS) ||
892 (eflags & ~GPIOEVENT_REQUEST_VALID_FLAGS)) {
893 ret = -EINVAL;
894 goto out_free_label;
895 }
896
897 /* This is just wrong: we don't look for events on output lines */
898 if (lflags & GPIOHANDLE_REQUEST_OUTPUT) {
899 ret = -EINVAL;
900 goto out_free_label;
901 }
902
903 desc = &gdev->descs[offset];
904 ret = gpiod_request(desc, le->label);
905 if (ret)
906 goto out_free_label;
907 le->desc = desc;
908 le->eflags = eflags;
909
910 if (lflags & GPIOHANDLE_REQUEST_ACTIVE_LOW)
911 set_bit(FLAG_ACTIVE_LOW, &desc->flags);
912 if (lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN)
913 set_bit(FLAG_OPEN_DRAIN, &desc->flags);
914 if (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE)
915 set_bit(FLAG_OPEN_SOURCE, &desc->flags);
916
917 ret = gpiod_direction_input(desc);
918 if (ret)
919 goto out_free_desc;
920
921 le->irq = gpiod_to_irq(desc);
922 if (le->irq <= 0) {
923 ret = -ENODEV;
924 goto out_free_desc;
925 }
926
927 if (eflags & GPIOEVENT_REQUEST_RISING_EDGE)
928 irqflags |= IRQF_TRIGGER_RISING;
929 if (eflags & GPIOEVENT_REQUEST_FALLING_EDGE)
930 irqflags |= IRQF_TRIGGER_FALLING;
931 irqflags |= IRQF_ONESHOT;
932 irqflags |= IRQF_SHARED;
933
934 INIT_KFIFO(le->events);
935 init_waitqueue_head(&le->wait);
936 mutex_init(&le->read_lock);
937
938 /* Request a thread to read the events */
939 ret = request_threaded_irq(le->irq,
940 lineevent_irq_handler,
941 lineevent_irq_thread,
942 irqflags,
943 le->label,
944 le);
945 if (ret)
946 goto out_free_desc;
947
948 fd = get_unused_fd_flags(O_RDONLY | O_CLOEXEC);
949 if (fd < 0) {
950 ret = fd;
951 goto out_free_irq;
952 }
953
954 file = anon_inode_getfile("gpio-event",
955 &lineevent_fileops,
956 le,
957 O_RDONLY | O_CLOEXEC);
958 if (IS_ERR(file)) {
959 ret = PTR_ERR(file);
960 goto out_put_unused_fd;
961 }
962
963 eventreq.fd = fd;
964 if (copy_to_user(ip, &eventreq, sizeof(eventreq))) {
965 /*
966 * fput() will trigger the release() callback, so do not go onto
967 * the regular error cleanup path here.
968 */
969 fput(file);
970 put_unused_fd(fd);
971 return -EFAULT;
972 }
973
974 fd_install(fd, file);
975
976 return 0;
977
978out_put_unused_fd:
979 put_unused_fd(fd);
980out_free_irq:
981 free_irq(le->irq, le);
982out_free_desc:
983 gpiod_free(le->desc);
984out_free_label:
985 kfree(le->label);
986out_free_le:
987 kfree(le);
988 put_device(&gdev->dev);
989 return ret;
990}
991
992/*
993 * gpio_ioctl() - ioctl handler for the GPIO chardev
994 */
995static long gpio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
996{
997 struct gpio_device *gdev = filp->private_data;
998 struct gpio_chip *chip = gdev->chip;
999 void __user *ip = (void __user *)arg;
1000
1001 /* We fail any subsequent ioctl():s when the chip is gone */
1002 if (!chip)
1003 return -ENODEV;
1004
1005 /* Fill in the struct and pass to userspace */
1006 if (cmd == GPIO_GET_CHIPINFO_IOCTL) {
1007 struct gpiochip_info chipinfo;
1008
1009 memset(&chipinfo, 0, sizeof(chipinfo));
1010
1011 strncpy(chipinfo.name, dev_name(&gdev->dev),
1012 sizeof(chipinfo.name));
1013 chipinfo.name[sizeof(chipinfo.name)-1] = '\0';
1014 strncpy(chipinfo.label, gdev->label,
1015 sizeof(chipinfo.label));
1016 chipinfo.label[sizeof(chipinfo.label)-1] = '\0';
1017 chipinfo.lines = gdev->ngpio;
1018 if (copy_to_user(ip, &chipinfo, sizeof(chipinfo)))
1019 return -EFAULT;
1020 return 0;
1021 } else if (cmd == GPIO_GET_LINEINFO_IOCTL) {
1022 struct gpioline_info lineinfo;
1023 struct gpio_desc *desc;
1024
1025 if (copy_from_user(&lineinfo, ip, sizeof(lineinfo)))
1026 return -EFAULT;
1027 if (lineinfo.line_offset >= gdev->ngpio)
1028 return -EINVAL;
1029
1030 desc = &gdev->descs[lineinfo.line_offset];
1031 if (desc->name) {
1032 strncpy(lineinfo.name, desc->name,
1033 sizeof(lineinfo.name));
1034 lineinfo.name[sizeof(lineinfo.name)-1] = '\0';
1035 } else {
1036 lineinfo.name[0] = '\0';
1037 }
1038 if (desc->label) {
1039 strncpy(lineinfo.consumer, desc->label,
1040 sizeof(lineinfo.consumer));
1041 lineinfo.consumer[sizeof(lineinfo.consumer)-1] = '\0';
1042 } else {
1043 lineinfo.consumer[0] = '\0';
1044 }
1045
1046 /*
1047 * Userspace only need to know that the kernel is using
1048 * this GPIO so it can't use it.
1049 */
1050 lineinfo.flags = 0;
1051 if (test_bit(FLAG_REQUESTED, &desc->flags) ||
1052 test_bit(FLAG_IS_HOGGED, &desc->flags) ||
1053 test_bit(FLAG_USED_AS_IRQ, &desc->flags) ||
1054 test_bit(FLAG_EXPORT, &desc->flags) ||
1055 test_bit(FLAG_SYSFS, &desc->flags))
1056 lineinfo.flags |= GPIOLINE_FLAG_KERNEL;
1057 if (test_bit(FLAG_IS_OUT, &desc->flags))
1058 lineinfo.flags |= GPIOLINE_FLAG_IS_OUT;
1059 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
1060 lineinfo.flags |= GPIOLINE_FLAG_ACTIVE_LOW;
1061 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags))
1062 lineinfo.flags |= GPIOLINE_FLAG_OPEN_DRAIN;
1063 if (test_bit(FLAG_OPEN_SOURCE, &desc->flags))
1064 lineinfo.flags |= GPIOLINE_FLAG_OPEN_SOURCE;
1065
1066 if (copy_to_user(ip, &lineinfo, sizeof(lineinfo)))
1067 return -EFAULT;
1068 return 0;
1069 } else if (cmd == GPIO_GET_LINEHANDLE_IOCTL) {
1070 return linehandle_create(gdev, ip);
1071 } else if (cmd == GPIO_GET_LINEEVENT_IOCTL) {
1072 return lineevent_create(gdev, ip);
1073 }
1074 return -EINVAL;
1075}
1076
1077#ifdef CONFIG_COMPAT
1078static long gpio_ioctl_compat(struct file *filp, unsigned int cmd,
1079 unsigned long arg)
1080{
1081 return gpio_ioctl(filp, cmd, (unsigned long)compat_ptr(arg));
1082}
1083#endif
1084
1085/**
1086 * gpio_chrdev_open() - open the chardev for ioctl operations
1087 * @inode: inode for this chardev
1088 * @filp: file struct for storing private data
1089 * Returns 0 on success
1090 */
1091static int gpio_chrdev_open(struct inode *inode, struct file *filp)
1092{
1093 struct gpio_device *gdev = container_of(inode->i_cdev,
1094 struct gpio_device, chrdev);
1095
1096 /* Fail on open if the backing gpiochip is gone */
1097 if (!gdev->chip)
1098 return -ENODEV;
1099 get_device(&gdev->dev);
1100 filp->private_data = gdev;
1101
1102 return nonseekable_open(inode, filp);
1103}
1104
1105/**
1106 * gpio_chrdev_release() - close chardev after ioctl operations
1107 * @inode: inode for this chardev
1108 * @filp: file struct for storing private data
1109 * Returns 0 on success
1110 */
1111static int gpio_chrdev_release(struct inode *inode, struct file *filp)
1112{
1113 struct gpio_device *gdev = container_of(inode->i_cdev,
1114 struct gpio_device, chrdev);
1115
1116 put_device(&gdev->dev);
1117 return 0;
1118}
1119
1120
1121static const struct file_operations gpio_fileops = {
1122 .release = gpio_chrdev_release,
1123 .open = gpio_chrdev_open,
1124 .owner = THIS_MODULE,
1125 .llseek = no_llseek,
1126 .unlocked_ioctl = gpio_ioctl,
1127#ifdef CONFIG_COMPAT
1128 .compat_ioctl = gpio_ioctl_compat,
1129#endif
1130};
1131
1132static void gpiodevice_release(struct device *dev)
1133{
1134 struct gpio_device *gdev = dev_get_drvdata(dev);
1135
1136 list_del(&gdev->list);
1137 ida_simple_remove(&gpio_ida, gdev->id);
1138 kfree_const(gdev->label);
1139 kfree(gdev->descs);
1140 kfree(gdev);
1141}
1142
1143static int gpiochip_setup_dev(struct gpio_device *gdev)
1144{
1145 int status;
1146
1147 cdev_init(&gdev->chrdev, &gpio_fileops);
1148 gdev->chrdev.owner = THIS_MODULE;
1149 gdev->dev.devt = MKDEV(MAJOR(gpio_devt), gdev->id);
1150
1151 status = cdev_device_add(&gdev->chrdev, &gdev->dev);
1152 if (status)
1153 return status;
1154
1155 chip_dbg(gdev->chip, "added GPIO chardev (%d:%d)\n",
1156 MAJOR(gpio_devt), gdev->id);
1157
1158 status = gpiochip_sysfs_register(gdev);
1159 if (status)
1160 goto err_remove_device;
1161
1162 /* From this point, the .release() function cleans up gpio_device */
1163 gdev->dev.release = gpiodevice_release;
1164 pr_debug("%s: registered GPIOs %d to %d on device: %s (%s)\n",
1165 __func__, gdev->base, gdev->base + gdev->ngpio - 1,
1166 dev_name(&gdev->dev), gdev->chip->label ? : "generic");
1167
1168 return 0;
1169
1170err_remove_device:
1171 cdev_device_del(&gdev->chrdev, &gdev->dev);
1172 return status;
1173}
1174
1175static void gpiochip_setup_devs(void)
1176{
1177 struct gpio_device *gdev;
1178 int err;
1179
1180 list_for_each_entry(gdev, &gpio_devices, list) {
1181 err = gpiochip_setup_dev(gdev);
1182 if (err)
1183 pr_err("%s: Failed to initialize gpio device (%d)\n",
1184 dev_name(&gdev->dev), err);
1185 }
1186}
1187
1188int gpiochip_add_data_with_key(struct gpio_chip *chip, void *data,
1189 struct lock_class_key *lock_key,
1190 struct lock_class_key *request_key)
1191{
1192 unsigned long flags;
1193 int status = 0;
1194 unsigned i;
1195 int base = chip->base;
1196 struct gpio_device *gdev;
1197
1198 /*
1199 * First: allocate and populate the internal stat container, and
1200 * set up the struct device.
1201 */
1202 gdev = kzalloc(sizeof(*gdev), GFP_KERNEL);
1203 if (!gdev)
1204 return -ENOMEM;
1205 gdev->dev.bus = &gpio_bus_type;
1206 gdev->chip = chip;
1207 chip->gpiodev = gdev;
1208 if (chip->parent) {
1209 gdev->dev.parent = chip->parent;
1210 gdev->dev.of_node = chip->parent->of_node;
1211 }
1212
1213#ifdef CONFIG_OF_GPIO
1214 /* If the gpiochip has an assigned OF node this takes precedence */
1215 if (chip->of_node)
1216 gdev->dev.of_node = chip->of_node;
1217#endif
1218
1219 gdev->id = ida_simple_get(&gpio_ida, 0, 0, GFP_KERNEL);
1220 if (gdev->id < 0) {
1221 status = gdev->id;
1222 goto err_free_gdev;
1223 }
1224 dev_set_name(&gdev->dev, "gpiochip%d", gdev->id);
1225 device_initialize(&gdev->dev);
1226 dev_set_drvdata(&gdev->dev, gdev);
1227 if (chip->parent && chip->parent->driver)
1228 gdev->owner = chip->parent->driver->owner;
1229 else if (chip->owner)
1230 /* TODO: remove chip->owner */
1231 gdev->owner = chip->owner;
1232 else
1233 gdev->owner = THIS_MODULE;
1234
1235 gdev->descs = kcalloc(chip->ngpio, sizeof(gdev->descs[0]), GFP_KERNEL);
1236 if (!gdev->descs) {
1237 status = -ENOMEM;
1238 goto err_free_gdev;
1239 }
1240
1241 if (chip->ngpio == 0) {
1242 chip_err(chip, "tried to insert a GPIO chip with zero lines\n");
1243 status = -EINVAL;
1244 goto err_free_descs;
1245 }
1246
1247 gdev->label = kstrdup_const(chip->label ?: "unknown", GFP_KERNEL);
1248 if (!gdev->label) {
1249 status = -ENOMEM;
1250 goto err_free_descs;
1251 }
1252
1253 gdev->ngpio = chip->ngpio;
1254 gdev->data = data;
1255
1256 spin_lock_irqsave(&gpio_lock, flags);
1257
1258 /*
1259 * TODO: this allocates a Linux GPIO number base in the global
1260 * GPIO numberspace for this chip. In the long run we want to
1261 * get *rid* of this numberspace and use only descriptors, but
1262 * it may be a pipe dream. It will not happen before we get rid
1263 * of the sysfs interface anyways.
1264 */
1265 if (base < 0) {
1266 base = gpiochip_find_base(chip->ngpio);
1267 if (base < 0) {
1268 status = base;
1269 spin_unlock_irqrestore(&gpio_lock, flags);
1270 goto err_free_label;
1271 }
1272 /*
1273 * TODO: it should not be necessary to reflect the assigned
1274 * base outside of the GPIO subsystem. Go over drivers and
1275 * see if anyone makes use of this, else drop this and assign
1276 * a poison instead.
1277 */
1278 chip->base = base;
1279 }
1280 gdev->base = base;
1281
1282 status = gpiodev_add_to_list(gdev);
1283 if (status) {
1284 spin_unlock_irqrestore(&gpio_lock, flags);
1285 goto err_free_label;
1286 }
1287
1288 spin_unlock_irqrestore(&gpio_lock, flags);
1289
1290 for (i = 0; i < chip->ngpio; i++) {
1291 struct gpio_desc *desc = &gdev->descs[i];
1292
1293 desc->gdev = gdev;
1294
1295 /* REVISIT: most hardware initializes GPIOs as inputs (often
1296 * with pullups enabled) so power usage is minimized. Linux
1297 * code should set the gpio direction first thing; but until
1298 * it does, and in case chip->get_direction is not set, we may
1299 * expose the wrong direction in sysfs.
1300 */
1301 desc->flags = !chip->direction_input ? (1 << FLAG_IS_OUT) : 0;
1302 }
1303
1304#ifdef CONFIG_PINCTRL
1305 INIT_LIST_HEAD(&gdev->pin_ranges);
1306#endif
1307
1308 status = gpiochip_set_desc_names(chip);
1309 if (status)
1310 goto err_remove_from_list;
1311
1312 status = gpiochip_irqchip_init_valid_mask(chip);
1313 if (status)
1314 goto err_remove_from_list;
1315
1316 status = gpiochip_init_valid_mask(chip);
1317 if (status)
1318 goto err_remove_irqchip_mask;
1319
1320 status = gpiochip_add_irqchip(chip, lock_key, request_key);
1321 if (status)
1322 goto err_remove_chip;
1323
1324 status = of_gpiochip_add(chip);
1325 if (status)
1326 goto err_remove_chip;
1327
1328 acpi_gpiochip_add(chip);
1329
1330 /*
1331 * By first adding the chardev, and then adding the device,
1332 * we get a device node entry in sysfs under
1333 * /sys/bus/gpio/devices/gpiochipN/dev that can be used for
1334 * coldplug of device nodes and other udev business.
1335 * We can do this only if gpiolib has been initialized.
1336 * Otherwise, defer until later.
1337 */
1338 if (gpiolib_initialized) {
1339 status = gpiochip_setup_dev(gdev);
1340 if (status)
1341 goto err_remove_chip;
1342 }
1343 return 0;
1344
1345err_remove_chip:
1346 acpi_gpiochip_remove(chip);
1347 gpiochip_free_hogs(chip);
1348 of_gpiochip_remove(chip);
1349 gpiochip_free_valid_mask(chip);
1350err_remove_irqchip_mask:
1351 gpiochip_irqchip_free_valid_mask(chip);
1352err_remove_from_list:
1353 spin_lock_irqsave(&gpio_lock, flags);
1354 list_del(&gdev->list);
1355 spin_unlock_irqrestore(&gpio_lock, flags);
1356err_free_label:
1357 kfree_const(gdev->label);
1358err_free_descs:
1359 kfree(gdev->descs);
1360err_free_gdev:
1361 ida_simple_remove(&gpio_ida, gdev->id);
1362 /* failures here can mean systems won't boot... */
1363 pr_err("%s: GPIOs %d..%d (%s) failed to register\n", __func__,
1364 gdev->base, gdev->base + gdev->ngpio - 1,
1365 chip->label ? : "generic");
1366 kfree(gdev);
1367 return status;
1368}
1369EXPORT_SYMBOL_GPL(gpiochip_add_data_with_key);
1370
1371/**
1372 * gpiochip_get_data() - get per-subdriver data for the chip
1373 * @chip: GPIO chip
1374 *
1375 * Returns:
1376 * The per-subdriver data for the chip.
1377 */
1378void *gpiochip_get_data(struct gpio_chip *chip)
1379{
1380 return chip->gpiodev->data;
1381}
1382EXPORT_SYMBOL_GPL(gpiochip_get_data);
1383
1384/**
1385 * gpiochip_remove() - unregister a gpio_chip
1386 * @chip: the chip to unregister
1387 *
1388 * A gpio_chip with any GPIOs still requested may not be removed.
1389 */
1390void gpiochip_remove(struct gpio_chip *chip)
1391{
1392 struct gpio_device *gdev = chip->gpiodev;
1393 struct gpio_desc *desc;
1394 unsigned long flags;
1395 unsigned i;
1396 bool requested = false;
1397
1398 /* FIXME: should the legacy sysfs handling be moved to gpio_device? */
1399 gpiochip_sysfs_unregister(gdev);
1400 gpiochip_free_hogs(chip);
1401 /* Numb the device, cancelling all outstanding operations */
1402 gdev->chip = NULL;
1403 gpiochip_irqchip_remove(chip);
1404 acpi_gpiochip_remove(chip);
1405 gpiochip_remove_pin_ranges(chip);
1406 of_gpiochip_remove(chip);
1407 gpiochip_free_valid_mask(chip);
1408 /*
1409 * We accept no more calls into the driver from this point, so
1410 * NULL the driver data pointer
1411 */
1412 gdev->data = NULL;
1413
1414 spin_lock_irqsave(&gpio_lock, flags);
1415 for (i = 0; i < gdev->ngpio; i++) {
1416 desc = &gdev->descs[i];
1417 if (test_bit(FLAG_REQUESTED, &desc->flags))
1418 requested = true;
1419 }
1420 spin_unlock_irqrestore(&gpio_lock, flags);
1421
1422 if (requested)
1423 dev_crit(&gdev->dev,
1424 "REMOVING GPIOCHIP WITH GPIOS STILL REQUESTED\n");
1425
1426 /*
1427 * The gpiochip side puts its use of the device to rest here:
1428 * if there are no userspace clients, the chardev and device will
1429 * be removed, else it will be dangling until the last user is
1430 * gone.
1431 */
1432 cdev_device_del(&gdev->chrdev, &gdev->dev);
1433 put_device(&gdev->dev);
1434}
1435EXPORT_SYMBOL_GPL(gpiochip_remove);
1436
1437static void devm_gpio_chip_release(struct device *dev, void *res)
1438{
1439 struct gpio_chip *chip = *(struct gpio_chip **)res;
1440
1441 gpiochip_remove(chip);
1442}
1443
1444static int devm_gpio_chip_match(struct device *dev, void *res, void *data)
1445
1446{
1447 struct gpio_chip **r = res;
1448
1449 if (!r || !*r) {
1450 WARN_ON(!r || !*r);
1451 return 0;
1452 }
1453
1454 return *r == data;
1455}
1456
1457/**
1458 * devm_gpiochip_add_data() - Resource manager gpiochip_add_data()
1459 * @dev: the device pointer on which irq_chip belongs to.
1460 * @chip: the chip to register, with chip->base initialized
1461 * @data: driver-private data associated with this chip
1462 *
1463 * Context: potentially before irqs will work
1464 *
1465 * The gpio chip automatically be released when the device is unbound.
1466 *
1467 * Returns:
1468 * A negative errno if the chip can't be registered, such as because the
1469 * chip->base is invalid or already associated with a different chip.
1470 * Otherwise it returns zero as a success code.
1471 */
1472int devm_gpiochip_add_data(struct device *dev, struct gpio_chip *chip,
1473 void *data)
1474{
1475 struct gpio_chip **ptr;
1476 int ret;
1477
1478 ptr = devres_alloc(devm_gpio_chip_release, sizeof(*ptr),
1479 GFP_KERNEL);
1480 if (!ptr)
1481 return -ENOMEM;
1482
1483 ret = gpiochip_add_data(chip, data);
1484 if (ret < 0) {
1485 devres_free(ptr);
1486 return ret;
1487 }
1488
1489 *ptr = chip;
1490 devres_add(dev, ptr);
1491
1492 return 0;
1493}
1494EXPORT_SYMBOL_GPL(devm_gpiochip_add_data);
1495
1496/**
1497 * devm_gpiochip_remove() - Resource manager of gpiochip_remove()
1498 * @dev: device for which which resource was allocated
1499 * @chip: the chip to remove
1500 *
1501 * A gpio_chip with any GPIOs still requested may not be removed.
1502 */
1503void devm_gpiochip_remove(struct device *dev, struct gpio_chip *chip)
1504{
1505 int ret;
1506
1507 ret = devres_release(dev, devm_gpio_chip_release,
1508 devm_gpio_chip_match, chip);
1509 WARN_ON(ret);
1510}
1511EXPORT_SYMBOL_GPL(devm_gpiochip_remove);
1512
1513/**
1514 * gpiochip_find() - iterator for locating a specific gpio_chip
1515 * @data: data to pass to match function
1516 * @match: Callback function to check gpio_chip
1517 *
1518 * Similar to bus_find_device. It returns a reference to a gpio_chip as
1519 * determined by a user supplied @match callback. The callback should return
1520 * 0 if the device doesn't match and non-zero if it does. If the callback is
1521 * non-zero, this function will return to the caller and not iterate over any
1522 * more gpio_chips.
1523 */
1524struct gpio_chip *gpiochip_find(void *data,
1525 int (*match)(struct gpio_chip *chip,
1526 void *data))
1527{
1528 struct gpio_device *gdev;
1529 struct gpio_chip *chip = NULL;
1530 unsigned long flags;
1531
1532 spin_lock_irqsave(&gpio_lock, flags);
1533 list_for_each_entry(gdev, &gpio_devices, list)
1534 if (gdev->chip && match(gdev->chip, data)) {
1535 chip = gdev->chip;
1536 break;
1537 }
1538
1539 spin_unlock_irqrestore(&gpio_lock, flags);
1540
1541 return chip;
1542}
1543EXPORT_SYMBOL_GPL(gpiochip_find);
1544
1545static int gpiochip_match_name(struct gpio_chip *chip, void *data)
1546{
1547 const char *name = data;
1548
1549 return !strcmp(chip->label, name);
1550}
1551
1552static struct gpio_chip *find_chip_by_name(const char *name)
1553{
1554 return gpiochip_find((void *)name, gpiochip_match_name);
1555}
1556
1557#ifdef CONFIG_GPIOLIB_IRQCHIP
1558
1559/*
1560 * The following is irqchip helper code for gpiochips.
1561 */
1562
1563static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gpiochip)
1564{
1565 if (!gpiochip->irq.need_valid_mask)
1566 return 0;
1567
1568 gpiochip->irq.valid_mask = gpiochip_allocate_mask(gpiochip);
1569 if (!gpiochip->irq.valid_mask)
1570 return -ENOMEM;
1571
1572 return 0;
1573}
1574
1575static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gpiochip)
1576{
1577 kfree(gpiochip->irq.valid_mask);
1578 gpiochip->irq.valid_mask = NULL;
1579}
1580
1581bool gpiochip_irqchip_irq_valid(const struct gpio_chip *gpiochip,
1582 unsigned int offset)
1583{
1584 if (!gpiochip_line_is_valid(gpiochip, offset))
1585 return false;
1586 /* No mask means all valid */
1587 if (likely(!gpiochip->irq.valid_mask))
1588 return true;
1589 return test_bit(offset, gpiochip->irq.valid_mask);
1590}
1591EXPORT_SYMBOL_GPL(gpiochip_irqchip_irq_valid);
1592
1593/**
1594 * gpiochip_set_cascaded_irqchip() - connects a cascaded irqchip to a gpiochip
1595 * @gpiochip: the gpiochip to set the irqchip chain to
1596 * @irqchip: the irqchip to chain to the gpiochip
1597 * @parent_irq: the irq number corresponding to the parent IRQ for this
1598 * chained irqchip
1599 * @parent_handler: the parent interrupt handler for the accumulated IRQ
1600 * coming out of the gpiochip. If the interrupt is nested rather than
1601 * cascaded, pass NULL in this handler argument
1602 */
1603static void gpiochip_set_cascaded_irqchip(struct gpio_chip *gpiochip,
1604 struct irq_chip *irqchip,
1605 unsigned int parent_irq,
1606 irq_flow_handler_t parent_handler)
1607{
1608 unsigned int offset;
1609
1610 if (!gpiochip->irq.domain) {
1611 chip_err(gpiochip, "called %s before setting up irqchip\n",
1612 __func__);
1613 return;
1614 }
1615
1616 if (parent_handler) {
1617 if (gpiochip->can_sleep) {
1618 chip_err(gpiochip,
1619 "you cannot have chained interrupts on a "
1620 "chip that may sleep\n");
1621 return;
1622 }
1623 /*
1624 * The parent irqchip is already using the chip_data for this
1625 * irqchip, so our callbacks simply use the handler_data.
1626 */
1627 irq_set_chained_handler_and_data(parent_irq, parent_handler,
1628 gpiochip);
1629
1630 gpiochip->irq.parents = &parent_irq;
1631 gpiochip->irq.num_parents = 1;
1632 }
1633
1634 /* Set the parent IRQ for all affected IRQs */
1635 for (offset = 0; offset < gpiochip->ngpio; offset++) {
1636 if (!gpiochip_irqchip_irq_valid(gpiochip, offset))
1637 continue;
1638 irq_set_parent(irq_find_mapping(gpiochip->irq.domain, offset),
1639 parent_irq);
1640 }
1641}
1642
1643/**
1644 * gpiochip_set_chained_irqchip() - connects a chained irqchip to a gpiochip
1645 * @gpiochip: the gpiochip to set the irqchip chain to
1646 * @irqchip: the irqchip to chain to the gpiochip
1647 * @parent_irq: the irq number corresponding to the parent IRQ for this
1648 * chained irqchip
1649 * @parent_handler: the parent interrupt handler for the accumulated IRQ
1650 * coming out of the gpiochip. If the interrupt is nested rather than
1651 * cascaded, pass NULL in this handler argument
1652 */
1653void gpiochip_set_chained_irqchip(struct gpio_chip *gpiochip,
1654 struct irq_chip *irqchip,
1655 unsigned int parent_irq,
1656 irq_flow_handler_t parent_handler)
1657{
1658 if (gpiochip->irq.threaded) {
1659 chip_err(gpiochip, "tried to chain a threaded gpiochip\n");
1660 return;
1661 }
1662
1663 gpiochip_set_cascaded_irqchip(gpiochip, irqchip, parent_irq,
1664 parent_handler);
1665}
1666EXPORT_SYMBOL_GPL(gpiochip_set_chained_irqchip);
1667
1668/**
1669 * gpiochip_set_nested_irqchip() - connects a nested irqchip to a gpiochip
1670 * @gpiochip: the gpiochip to set the irqchip nested handler to
1671 * @irqchip: the irqchip to nest to the gpiochip
1672 * @parent_irq: the irq number corresponding to the parent IRQ for this
1673 * nested irqchip
1674 */
1675void gpiochip_set_nested_irqchip(struct gpio_chip *gpiochip,
1676 struct irq_chip *irqchip,
1677 unsigned int parent_irq)
1678{
1679 gpiochip_set_cascaded_irqchip(gpiochip, irqchip, parent_irq,
1680 NULL);
1681}
1682EXPORT_SYMBOL_GPL(gpiochip_set_nested_irqchip);
1683
1684/**
1685 * gpiochip_irq_map() - maps an IRQ into a GPIO irqchip
1686 * @d: the irqdomain used by this irqchip
1687 * @irq: the global irq number used by this GPIO irqchip irq
1688 * @hwirq: the local IRQ/GPIO line offset on this gpiochip
1689 *
1690 * This function will set up the mapping for a certain IRQ line on a
1691 * gpiochip by assigning the gpiochip as chip data, and using the irqchip
1692 * stored inside the gpiochip.
1693 */
1694int gpiochip_irq_map(struct irq_domain *d, unsigned int irq,
1695 irq_hw_number_t hwirq)
1696{
1697 struct gpio_chip *chip = d->host_data;
1698 int err = 0;
1699
1700 if (!gpiochip_irqchip_irq_valid(chip, hwirq))
1701 return -ENXIO;
1702
1703 irq_set_chip_data(irq, chip);
1704 /*
1705 * This lock class tells lockdep that GPIO irqs are in a different
1706 * category than their parents, so it won't report false recursion.
1707 */
1708 irq_set_lockdep_class(irq, chip->irq.lock_key, chip->irq.request_key);
1709 irq_set_chip_and_handler(irq, chip->irq.chip, chip->irq.handler);
1710 /* Chips that use nested thread handlers have them marked */
1711 if (chip->irq.threaded)
1712 irq_set_nested_thread(irq, 1);
1713 irq_set_noprobe(irq);
1714
1715 if (chip->irq.num_parents == 1)
1716 err = irq_set_parent(irq, chip->irq.parents[0]);
1717 else if (chip->irq.map)
1718 err = irq_set_parent(irq, chip->irq.map[hwirq]);
1719
1720 if (err < 0)
1721 return err;
1722
1723 /*
1724 * No set-up of the hardware will happen if IRQ_TYPE_NONE
1725 * is passed as default type.
1726 */
1727 if (chip->irq.default_type != IRQ_TYPE_NONE)
1728 irq_set_irq_type(irq, chip->irq.default_type);
1729
1730 return 0;
1731}
1732EXPORT_SYMBOL_GPL(gpiochip_irq_map);
1733
1734void gpiochip_irq_unmap(struct irq_domain *d, unsigned int irq)
1735{
1736 struct gpio_chip *chip = d->host_data;
1737
1738 if (chip->irq.threaded)
1739 irq_set_nested_thread(irq, 0);
1740 irq_set_chip_and_handler(irq, NULL, NULL);
1741 irq_set_chip_data(irq, NULL);
1742}
1743EXPORT_SYMBOL_GPL(gpiochip_irq_unmap);
1744
1745static const struct irq_domain_ops gpiochip_domain_ops = {
1746 .map = gpiochip_irq_map,
1747 .unmap = gpiochip_irq_unmap,
1748 /* Virtually all GPIO irqchips are twocell:ed */
1749 .xlate = irq_domain_xlate_twocell,
1750};
1751
1752static int gpiochip_irq_reqres(struct irq_data *d)
1753{
1754 struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
1755
1756 if (!try_module_get(chip->gpiodev->owner))
1757 return -ENODEV;
1758
1759 if (gpiochip_lock_as_irq(chip, d->hwirq)) {
1760 chip_err(chip,
1761 "unable to lock HW IRQ %lu for IRQ\n",
1762 d->hwirq);
1763 module_put(chip->gpiodev->owner);
1764 return -EINVAL;
1765 }
1766 return 0;
1767}
1768
1769static void gpiochip_irq_relres(struct irq_data *d)
1770{
1771 struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
1772
1773 gpiochip_unlock_as_irq(chip, d->hwirq);
1774 module_put(chip->gpiodev->owner);
1775}
1776
1777static int gpiochip_to_irq(struct gpio_chip *chip, unsigned offset)
1778{
1779 if (!gpiochip_irqchip_irq_valid(chip, offset))
1780 return -ENXIO;
1781
1782 return irq_create_mapping(chip->irq.domain, offset);
1783}
1784
1785/**
1786 * gpiochip_add_irqchip() - adds an IRQ chip to a GPIO chip
1787 * @gpiochip: the GPIO chip to add the IRQ chip to
1788 * @lock_key: lockdep class for IRQ lock
1789 * @request_key: lockdep class for IRQ request
1790 */
1791static int gpiochip_add_irqchip(struct gpio_chip *gpiochip,
1792 struct lock_class_key *lock_key,
1793 struct lock_class_key *request_key)
1794{
1795 struct irq_chip *irqchip = gpiochip->irq.chip;
1796 const struct irq_domain_ops *ops;
1797 struct device_node *np;
1798 unsigned int type;
1799 unsigned int i;
1800
1801 if (!irqchip)
1802 return 0;
1803
1804 if (gpiochip->irq.parent_handler && gpiochip->can_sleep) {
1805 chip_err(gpiochip, "you cannot have chained interrupts on a "
1806 "chip that may sleep\n");
1807 return -EINVAL;
1808 }
1809
1810 np = gpiochip->gpiodev->dev.of_node;
1811 type = gpiochip->irq.default_type;
1812
1813 /*
1814 * Specifying a default trigger is a terrible idea if DT or ACPI is
1815 * used to configure the interrupts, as you may end up with
1816 * conflicting triggers. Tell the user, and reset to NONE.
1817 */
1818 if (WARN(np && type != IRQ_TYPE_NONE,
1819 "%s: Ignoring %u default trigger\n", np->full_name, type))
1820 type = IRQ_TYPE_NONE;
1821
1822 if (has_acpi_companion(gpiochip->parent) && type != IRQ_TYPE_NONE) {
1823 acpi_handle_warn(ACPI_HANDLE(gpiochip->parent),
1824 "Ignoring %u default trigger\n", type);
1825 type = IRQ_TYPE_NONE;
1826 }
1827
1828 gpiochip->to_irq = gpiochip_to_irq;
1829 gpiochip->irq.default_type = type;
1830 gpiochip->irq.lock_key = lock_key;
1831 gpiochip->irq.request_key = request_key;
1832
1833 if (gpiochip->irq.domain_ops)
1834 ops = gpiochip->irq.domain_ops;
1835 else
1836 ops = &gpiochip_domain_ops;
1837
1838 gpiochip->irq.domain = irq_domain_add_simple(np, gpiochip->ngpio,
1839 gpiochip->irq.first,
1840 ops, gpiochip);
1841 if (!gpiochip->irq.domain)
1842 return -EINVAL;
1843
1844 /*
1845 * It is possible for a driver to override this, but only if the
1846 * alternative functions are both implemented.
1847 */
1848 if (!irqchip->irq_request_resources &&
1849 !irqchip->irq_release_resources) {
1850 irqchip->irq_request_resources = gpiochip_irq_reqres;
1851 irqchip->irq_release_resources = gpiochip_irq_relres;
1852 }
1853
1854 if (gpiochip->irq.parent_handler) {
1855 void *data = gpiochip->irq.parent_handler_data ?: gpiochip;
1856
1857 for (i = 0; i < gpiochip->irq.num_parents; i++) {
1858 /*
1859 * The parent IRQ chip is already using the chip_data
1860 * for this IRQ chip, so our callbacks simply use the
1861 * handler_data.
1862 */
1863 irq_set_chained_handler_and_data(gpiochip->irq.parents[i],
1864 gpiochip->irq.parent_handler,
1865 data);
1866 }
1867 }
1868
1869 acpi_gpiochip_request_interrupts(gpiochip);
1870
1871 return 0;
1872}
1873
1874/**
1875 * gpiochip_irqchip_remove() - removes an irqchip added to a gpiochip
1876 * @gpiochip: the gpiochip to remove the irqchip from
1877 *
1878 * This is called only from gpiochip_remove()
1879 */
1880static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip)
1881{
1882 unsigned int offset;
1883
1884 acpi_gpiochip_free_interrupts(gpiochip);
1885
1886 if (gpiochip->irq.chip && gpiochip->irq.parent_handler) {
1887 struct gpio_irq_chip *irq = &gpiochip->irq;
1888 unsigned int i;
1889
1890 for (i = 0; i < irq->num_parents; i++)
1891 irq_set_chained_handler_and_data(irq->parents[i],
1892 NULL, NULL);
1893 }
1894
1895 /* Remove all IRQ mappings and delete the domain */
1896 if (gpiochip->irq.domain) {
1897 unsigned int irq;
1898
1899 for (offset = 0; offset < gpiochip->ngpio; offset++) {
1900 if (!gpiochip_irqchip_irq_valid(gpiochip, offset))
1901 continue;
1902
1903 irq = irq_find_mapping(gpiochip->irq.domain, offset);
1904 irq_dispose_mapping(irq);
1905 }
1906
1907 irq_domain_remove(gpiochip->irq.domain);
1908 }
1909
1910 if (gpiochip->irq.chip) {
1911 gpiochip->irq.chip->irq_request_resources = NULL;
1912 gpiochip->irq.chip->irq_release_resources = NULL;
1913 gpiochip->irq.chip = NULL;
1914 }
1915
1916 gpiochip_irqchip_free_valid_mask(gpiochip);
1917}
1918
1919/**
1920 * gpiochip_irqchip_add_key() - adds an irqchip to a gpiochip
1921 * @gpiochip: the gpiochip to add the irqchip to
1922 * @irqchip: the irqchip to add to the gpiochip
1923 * @first_irq: if not dynamically assigned, the base (first) IRQ to
1924 * allocate gpiochip irqs from
1925 * @handler: the irq handler to use (often a predefined irq core function)
1926 * @type: the default type for IRQs on this irqchip, pass IRQ_TYPE_NONE
1927 * to have the core avoid setting up any default type in the hardware.
1928 * @threaded: whether this irqchip uses a nested thread handler
1929 * @lock_key: lockdep class for IRQ lock
1930 * @request_key: lockdep class for IRQ request
1931 *
1932 * This function closely associates a certain irqchip with a certain
1933 * gpiochip, providing an irq domain to translate the local IRQs to
1934 * global irqs in the gpiolib core, and making sure that the gpiochip
1935 * is passed as chip data to all related functions. Driver callbacks
1936 * need to use gpiochip_get_data() to get their local state containers back
1937 * from the gpiochip passed as chip data. An irqdomain will be stored
1938 * in the gpiochip that shall be used by the driver to handle IRQ number
1939 * translation. The gpiochip will need to be initialized and registered
1940 * before calling this function.
1941 *
1942 * This function will handle two cell:ed simple IRQs and assumes all
1943 * the pins on the gpiochip can generate a unique IRQ. Everything else
1944 * need to be open coded.
1945 */
1946int gpiochip_irqchip_add_key(struct gpio_chip *gpiochip,
1947 struct irq_chip *irqchip,
1948 unsigned int first_irq,
1949 irq_flow_handler_t handler,
1950 unsigned int type,
1951 bool threaded,
1952 struct lock_class_key *lock_key,
1953 struct lock_class_key *request_key)
1954{
1955 struct device_node *of_node;
1956
1957 if (!gpiochip || !irqchip)
1958 return -EINVAL;
1959
1960 if (!gpiochip->parent) {
1961 pr_err("missing gpiochip .dev parent pointer\n");
1962 return -EINVAL;
1963 }
1964 gpiochip->irq.threaded = threaded;
1965 of_node = gpiochip->parent->of_node;
1966#ifdef CONFIG_OF_GPIO
1967 /*
1968 * If the gpiochip has an assigned OF node this takes precedence
1969 * FIXME: get rid of this and use gpiochip->parent->of_node
1970 * everywhere
1971 */
1972 if (gpiochip->of_node)
1973 of_node = gpiochip->of_node;
1974#endif
1975 /*
1976 * Specifying a default trigger is a terrible idea if DT or ACPI is
1977 * used to configure the interrupts, as you may end-up with
1978 * conflicting triggers. Tell the user, and reset to NONE.
1979 */
1980 if (WARN(of_node && type != IRQ_TYPE_NONE,
1981 "%pOF: Ignoring %d default trigger\n", of_node, type))
1982 type = IRQ_TYPE_NONE;
1983 if (has_acpi_companion(gpiochip->parent) && type != IRQ_TYPE_NONE) {
1984 acpi_handle_warn(ACPI_HANDLE(gpiochip->parent),
1985 "Ignoring %d default trigger\n", type);
1986 type = IRQ_TYPE_NONE;
1987 }
1988
1989 gpiochip->irq.chip = irqchip;
1990 gpiochip->irq.handler = handler;
1991 gpiochip->irq.default_type = type;
1992 gpiochip->to_irq = gpiochip_to_irq;
1993 gpiochip->irq.lock_key = lock_key;
1994 gpiochip->irq.request_key = request_key;
1995 gpiochip->irq.domain = irq_domain_add_simple(of_node,
1996 gpiochip->ngpio, first_irq,
1997 &gpiochip_domain_ops, gpiochip);
1998 if (!gpiochip->irq.domain) {
1999 gpiochip->irq.chip = NULL;
2000 return -EINVAL;
2001 }
2002
2003 /*
2004 * It is possible for a driver to override this, but only if the
2005 * alternative functions are both implemented.
2006 */
2007 if (!irqchip->irq_request_resources &&
2008 !irqchip->irq_release_resources) {
2009 irqchip->irq_request_resources = gpiochip_irq_reqres;
2010 irqchip->irq_release_resources = gpiochip_irq_relres;
2011 }
2012
2013 acpi_gpiochip_request_interrupts(gpiochip);
2014
2015 return 0;
2016}
2017EXPORT_SYMBOL_GPL(gpiochip_irqchip_add_key);
2018
2019#else /* CONFIG_GPIOLIB_IRQCHIP */
2020
2021static inline int gpiochip_add_irqchip(struct gpio_chip *gpiochip,
2022 struct lock_class_key *lock_key,
2023 struct lock_class_key *request_key)
2024{
2025 return 0;
2026}
2027
2028static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip) {}
2029static inline int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gpiochip)
2030{
2031 return 0;
2032}
2033static inline void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gpiochip)
2034{ }
2035
2036#endif /* CONFIG_GPIOLIB_IRQCHIP */
2037
2038/**
2039 * gpiochip_generic_request() - request the gpio function for a pin
2040 * @chip: the gpiochip owning the GPIO
2041 * @offset: the offset of the GPIO to request for GPIO function
2042 */
2043int gpiochip_generic_request(struct gpio_chip *chip, unsigned offset)
2044{
2045 return pinctrl_gpio_request(chip->gpiodev->base + offset);
2046}
2047EXPORT_SYMBOL_GPL(gpiochip_generic_request);
2048
2049/**
2050 * gpiochip_generic_free() - free the gpio function from a pin
2051 * @chip: the gpiochip to request the gpio function for
2052 * @offset: the offset of the GPIO to free from GPIO function
2053 */
2054void gpiochip_generic_free(struct gpio_chip *chip, unsigned offset)
2055{
2056 pinctrl_gpio_free(chip->gpiodev->base + offset);
2057}
2058EXPORT_SYMBOL_GPL(gpiochip_generic_free);
2059
2060/**
2061 * gpiochip_generic_config() - apply configuration for a pin
2062 * @chip: the gpiochip owning the GPIO
2063 * @offset: the offset of the GPIO to apply the configuration
2064 * @config: the configuration to be applied
2065 */
2066int gpiochip_generic_config(struct gpio_chip *chip, unsigned offset,
2067 unsigned long config)
2068{
2069 return pinctrl_gpio_set_config(chip->gpiodev->base + offset, config);
2070}
2071EXPORT_SYMBOL_GPL(gpiochip_generic_config);
2072
2073#ifdef CONFIG_PINCTRL
2074
2075/**
2076 * gpiochip_add_pingroup_range() - add a range for GPIO <-> pin mapping
2077 * @chip: the gpiochip to add the range for
2078 * @pctldev: the pin controller to map to
2079 * @gpio_offset: the start offset in the current gpio_chip number space
2080 * @pin_group: name of the pin group inside the pin controller
2081 */
2082int gpiochip_add_pingroup_range(struct gpio_chip *chip,
2083 struct pinctrl_dev *pctldev,
2084 unsigned int gpio_offset, const char *pin_group)
2085{
2086 struct gpio_pin_range *pin_range;
2087 struct gpio_device *gdev = chip->gpiodev;
2088 int ret;
2089
2090 pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL);
2091 if (!pin_range) {
2092 chip_err(chip, "failed to allocate pin ranges\n");
2093 return -ENOMEM;
2094 }
2095
2096 /* Use local offset as range ID */
2097 pin_range->range.id = gpio_offset;
2098 pin_range->range.gc = chip;
2099 pin_range->range.name = chip->label;
2100 pin_range->range.base = gdev->base + gpio_offset;
2101 pin_range->pctldev = pctldev;
2102
2103 ret = pinctrl_get_group_pins(pctldev, pin_group,
2104 &pin_range->range.pins,
2105 &pin_range->range.npins);
2106 if (ret < 0) {
2107 kfree(pin_range);
2108 return ret;
2109 }
2110
2111 pinctrl_add_gpio_range(pctldev, &pin_range->range);
2112
2113 chip_dbg(chip, "created GPIO range %d->%d ==> %s PINGRP %s\n",
2114 gpio_offset, gpio_offset + pin_range->range.npins - 1,
2115 pinctrl_dev_get_devname(pctldev), pin_group);
2116
2117 list_add_tail(&pin_range->node, &gdev->pin_ranges);
2118
2119 return 0;
2120}
2121EXPORT_SYMBOL_GPL(gpiochip_add_pingroup_range);
2122
2123/**
2124 * gpiochip_add_pin_range() - add a range for GPIO <-> pin mapping
2125 * @chip: the gpiochip to add the range for
2126 * @pinctl_name: the dev_name() of the pin controller to map to
2127 * @gpio_offset: the start offset in the current gpio_chip number space
2128 * @pin_offset: the start offset in the pin controller number space
2129 * @npins: the number of pins from the offset of each pin space (GPIO and
2130 * pin controller) to accumulate in this range
2131 *
2132 * Returns:
2133 * 0 on success, or a negative error-code on failure.
2134 */
2135int gpiochip_add_pin_range(struct gpio_chip *chip, const char *pinctl_name,
2136 unsigned int gpio_offset, unsigned int pin_offset,
2137 unsigned int npins)
2138{
2139 struct gpio_pin_range *pin_range;
2140 struct gpio_device *gdev = chip->gpiodev;
2141 int ret;
2142
2143 pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL);
2144 if (!pin_range) {
2145 chip_err(chip, "failed to allocate pin ranges\n");
2146 return -ENOMEM;
2147 }
2148
2149 /* Use local offset as range ID */
2150 pin_range->range.id = gpio_offset;
2151 pin_range->range.gc = chip;
2152 pin_range->range.name = chip->label;
2153 pin_range->range.base = gdev->base + gpio_offset;
2154 pin_range->range.pin_base = pin_offset;
2155 pin_range->range.npins = npins;
2156 pin_range->pctldev = pinctrl_find_and_add_gpio_range(pinctl_name,
2157 &pin_range->range);
2158 if (IS_ERR(pin_range->pctldev)) {
2159 ret = PTR_ERR(pin_range->pctldev);
2160 chip_err(chip, "could not create pin range\n");
2161 kfree(pin_range);
2162 return ret;
2163 }
2164 chip_dbg(chip, "created GPIO range %d->%d ==> %s PIN %d->%d\n",
2165 gpio_offset, gpio_offset + npins - 1,
2166 pinctl_name,
2167 pin_offset, pin_offset + npins - 1);
2168
2169 list_add_tail(&pin_range->node, &gdev->pin_ranges);
2170
2171 return 0;
2172}
2173EXPORT_SYMBOL_GPL(gpiochip_add_pin_range);
2174
2175/**
2176 * gpiochip_remove_pin_ranges() - remove all the GPIO <-> pin mappings
2177 * @chip: the chip to remove all the mappings for
2178 */
2179void gpiochip_remove_pin_ranges(struct gpio_chip *chip)
2180{
2181 struct gpio_pin_range *pin_range, *tmp;
2182 struct gpio_device *gdev = chip->gpiodev;
2183
2184 list_for_each_entry_safe(pin_range, tmp, &gdev->pin_ranges, node) {
2185 list_del(&pin_range->node);
2186 pinctrl_remove_gpio_range(pin_range->pctldev,
2187 &pin_range->range);
2188 kfree(pin_range);
2189 }
2190}
2191EXPORT_SYMBOL_GPL(gpiochip_remove_pin_ranges);
2192
2193#endif /* CONFIG_PINCTRL */
2194
2195/* These "optional" allocation calls help prevent drivers from stomping
2196 * on each other, and help provide better diagnostics in debugfs.
2197 * They're called even less than the "set direction" calls.
2198 */
2199static int gpiod_request_commit(struct gpio_desc *desc, const char *label)
2200{
2201 struct gpio_chip *chip = desc->gdev->chip;
2202 int status;
2203 unsigned long flags;
2204
2205 spin_lock_irqsave(&gpio_lock, flags);
2206
2207 /* NOTE: gpio_request() can be called in early boot,
2208 * before IRQs are enabled, for non-sleeping (SOC) GPIOs.
2209 */
2210
2211 if (test_and_set_bit(FLAG_REQUESTED, &desc->flags) == 0) {
2212 desc_set_label(desc, label ? : "?");
2213 status = 0;
2214 } else {
2215 status = -EBUSY;
2216 goto done;
2217 }
2218
2219 if (chip->request) {
2220 /* chip->request may sleep */
2221 spin_unlock_irqrestore(&gpio_lock, flags);
2222 status = chip->request(chip, gpio_chip_hwgpio(desc));
2223 spin_lock_irqsave(&gpio_lock, flags);
2224
2225 if (status < 0) {
2226 desc_set_label(desc, NULL);
2227 clear_bit(FLAG_REQUESTED, &desc->flags);
2228 goto done;
2229 }
2230 }
2231 if (chip->get_direction) {
2232 /* chip->get_direction may sleep */
2233 spin_unlock_irqrestore(&gpio_lock, flags);
2234 gpiod_get_direction(desc);
2235 spin_lock_irqsave(&gpio_lock, flags);
2236 }
2237done:
2238 spin_unlock_irqrestore(&gpio_lock, flags);
2239 return status;
2240}
2241
2242/*
2243 * This descriptor validation needs to be inserted verbatim into each
2244 * function taking a descriptor, so we need to use a preprocessor
2245 * macro to avoid endless duplication. If the desc is NULL it is an
2246 * optional GPIO and calls should just bail out.
2247 */
2248static int validate_desc(const struct gpio_desc *desc, const char *func)
2249{
2250 if (!desc)
2251 return 0;
2252 if (IS_ERR(desc)) {
2253 pr_warn("%s: invalid GPIO (errorpointer)\n", func);
2254 return PTR_ERR(desc);
2255 }
2256 if (!desc->gdev) {
2257 pr_warn("%s: invalid GPIO (no device)\n", func);
2258 return -EINVAL;
2259 }
2260 if (!desc->gdev->chip) {
2261 dev_warn(&desc->gdev->dev,
2262 "%s: backing chip is gone\n", func);
2263 return 0;
2264 }
2265 return 1;
2266}
2267
2268#define VALIDATE_DESC(desc) do { \
2269 int __valid = validate_desc(desc, __func__); \
2270 if (__valid <= 0) \
2271 return __valid; \
2272 } while (0)
2273
2274#define VALIDATE_DESC_VOID(desc) do { \
2275 int __valid = validate_desc(desc, __func__); \
2276 if (__valid <= 0) \
2277 return; \
2278 } while (0)
2279
2280int gpiod_request(struct gpio_desc *desc, const char *label)
2281{
2282 int status = -EPROBE_DEFER;
2283 struct gpio_device *gdev;
2284
2285 VALIDATE_DESC(desc);
2286 gdev = desc->gdev;
2287
2288 if (try_module_get(gdev->owner)) {
2289 status = gpiod_request_commit(desc, label);
2290 if (status < 0)
2291 module_put(gdev->owner);
2292 else
2293 get_device(&gdev->dev);
2294 }
2295
2296 if (status)
2297 gpiod_dbg(desc, "%s: status %d\n", __func__, status);
2298
2299 return status;
2300}
2301
2302static bool gpiod_free_commit(struct gpio_desc *desc)
2303{
2304 bool ret = false;
2305 unsigned long flags;
2306 struct gpio_chip *chip;
2307
2308 might_sleep();
2309
2310 gpiod_unexport(desc);
2311
2312 spin_lock_irqsave(&gpio_lock, flags);
2313
2314 chip = desc->gdev->chip;
2315 if (chip && test_bit(FLAG_REQUESTED, &desc->flags)) {
2316 if (chip->free) {
2317 spin_unlock_irqrestore(&gpio_lock, flags);
2318 might_sleep_if(chip->can_sleep);
2319 chip->free(chip, gpio_chip_hwgpio(desc));
2320 spin_lock_irqsave(&gpio_lock, flags);
2321 }
2322 desc_set_label(desc, NULL);
2323 clear_bit(FLAG_ACTIVE_LOW, &desc->flags);
2324 clear_bit(FLAG_REQUESTED, &desc->flags);
2325 clear_bit(FLAG_OPEN_DRAIN, &desc->flags);
2326 clear_bit(FLAG_OPEN_SOURCE, &desc->flags);
2327 clear_bit(FLAG_IS_HOGGED, &desc->flags);
2328 ret = true;
2329 }
2330
2331 spin_unlock_irqrestore(&gpio_lock, flags);
2332 return ret;
2333}
2334
2335void gpiod_free(struct gpio_desc *desc)
2336{
2337 if (desc && desc->gdev && gpiod_free_commit(desc)) {
2338 module_put(desc->gdev->owner);
2339 put_device(&desc->gdev->dev);
2340 } else {
2341 WARN_ON(extra_checks);
2342 }
2343}
2344
2345/**
2346 * gpiochip_is_requested - return string iff signal was requested
2347 * @chip: controller managing the signal
2348 * @offset: of signal within controller's 0..(ngpio - 1) range
2349 *
2350 * Returns NULL if the GPIO is not currently requested, else a string.
2351 * The string returned is the label passed to gpio_request(); if none has been
2352 * passed it is a meaningless, non-NULL constant.
2353 *
2354 * This function is for use by GPIO controller drivers. The label can
2355 * help with diagnostics, and knowing that the signal is used as a GPIO
2356 * can help avoid accidentally multiplexing it to another controller.
2357 */
2358const char *gpiochip_is_requested(struct gpio_chip *chip, unsigned offset)
2359{
2360 struct gpio_desc *desc;
2361
2362 if (offset >= chip->ngpio)
2363 return NULL;
2364
2365 desc = &chip->gpiodev->descs[offset];
2366
2367 if (test_bit(FLAG_REQUESTED, &desc->flags) == 0)
2368 return NULL;
2369 return desc->label;
2370}
2371EXPORT_SYMBOL_GPL(gpiochip_is_requested);
2372
2373/**
2374 * gpiochip_request_own_desc - Allow GPIO chip to request its own descriptor
2375 * @chip: GPIO chip
2376 * @hwnum: hardware number of the GPIO for which to request the descriptor
2377 * @label: label for the GPIO
2378 *
2379 * Function allows GPIO chip drivers to request and use their own GPIO
2380 * descriptors via gpiolib API. Difference to gpiod_request() is that this
2381 * function will not increase reference count of the GPIO chip module. This
2382 * allows the GPIO chip module to be unloaded as needed (we assume that the
2383 * GPIO chip driver handles freeing the GPIOs it has requested).
2384 *
2385 * Returns:
2386 * A pointer to the GPIO descriptor, or an ERR_PTR()-encoded negative error
2387 * code on failure.
2388 */
2389struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *chip, u16 hwnum,
2390 const char *label)
2391{
2392 struct gpio_desc *desc = gpiochip_get_desc(chip, hwnum);
2393 int err;
2394
2395 if (IS_ERR(desc)) {
2396 chip_err(chip, "failed to get GPIO descriptor\n");
2397 return desc;
2398 }
2399
2400 err = gpiod_request_commit(desc, label);
2401 if (err < 0)
2402 return ERR_PTR(err);
2403
2404 return desc;
2405}
2406EXPORT_SYMBOL_GPL(gpiochip_request_own_desc);
2407
2408/**
2409 * gpiochip_free_own_desc - Free GPIO requested by the chip driver
2410 * @desc: GPIO descriptor to free
2411 *
2412 * Function frees the given GPIO requested previously with
2413 * gpiochip_request_own_desc().
2414 */
2415void gpiochip_free_own_desc(struct gpio_desc *desc)
2416{
2417 if (desc)
2418 gpiod_free_commit(desc);
2419}
2420EXPORT_SYMBOL_GPL(gpiochip_free_own_desc);
2421
2422/*
2423 * Drivers MUST set GPIO direction before making get/set calls. In
2424 * some cases this is done in early boot, before IRQs are enabled.
2425 *
2426 * As a rule these aren't called more than once (except for drivers
2427 * using the open-drain emulation idiom) so these are natural places
2428 * to accumulate extra debugging checks. Note that we can't (yet)
2429 * rely on gpio_request() having been called beforehand.
2430 */
2431
2432/**
2433 * gpiod_direction_input - set the GPIO direction to input
2434 * @desc: GPIO to set to input
2435 *
2436 * Set the direction of the passed GPIO to input, such as gpiod_get_value() can
2437 * be called safely on it.
2438 *
2439 * Return 0 in case of success, else an error code.
2440 */
2441int gpiod_direction_input(struct gpio_desc *desc)
2442{
2443 struct gpio_chip *chip;
2444 int status = -EINVAL;
2445
2446 VALIDATE_DESC(desc);
2447 chip = desc->gdev->chip;
2448
2449 if (!chip->get || !chip->direction_input) {
2450 gpiod_warn(desc,
2451 "%s: missing get() or direction_input() operations\n",
2452 __func__);
2453 return -EIO;
2454 }
2455
2456 status = chip->direction_input(chip, gpio_chip_hwgpio(desc));
2457 if (status == 0)
2458 clear_bit(FLAG_IS_OUT, &desc->flags);
2459
2460 trace_gpio_direction(desc_to_gpio(desc), 1, status);
2461
2462 return status;
2463}
2464EXPORT_SYMBOL_GPL(gpiod_direction_input);
2465
2466static int gpio_set_drive_single_ended(struct gpio_chip *gc, unsigned offset,
2467 enum pin_config_param mode)
2468{
2469 unsigned long config = { PIN_CONF_PACKED(mode, 0) };
2470
2471 return gc->set_config ? gc->set_config(gc, offset, config) : -ENOTSUPP;
2472}
2473
2474static int gpiod_direction_output_raw_commit(struct gpio_desc *desc, int value)
2475{
2476 struct gpio_chip *gc = desc->gdev->chip;
2477 int val = !!value;
2478 int ret;
2479
2480 if (!gc->set || !gc->direction_output) {
2481 gpiod_warn(desc,
2482 "%s: missing set() or direction_output() operations\n",
2483 __func__);
2484 return -EIO;
2485 }
2486
2487 ret = gc->direction_output(gc, gpio_chip_hwgpio(desc), val);
2488 if (!ret)
2489 set_bit(FLAG_IS_OUT, &desc->flags);
2490 trace_gpio_value(desc_to_gpio(desc), 0, val);
2491 trace_gpio_direction(desc_to_gpio(desc), 0, ret);
2492 return ret;
2493}
2494
2495/**
2496 * gpiod_direction_output_raw - set the GPIO direction to output
2497 * @desc: GPIO to set to output
2498 * @value: initial output value of the GPIO
2499 *
2500 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
2501 * be called safely on it. The initial value of the output must be specified
2502 * as raw value on the physical line without regard for the ACTIVE_LOW status.
2503 *
2504 * Return 0 in case of success, else an error code.
2505 */
2506int gpiod_direction_output_raw(struct gpio_desc *desc, int value)
2507{
2508 VALIDATE_DESC(desc);
2509 return gpiod_direction_output_raw_commit(desc, value);
2510}
2511EXPORT_SYMBOL_GPL(gpiod_direction_output_raw);
2512
2513/**
2514 * gpiod_direction_output - set the GPIO direction to output
2515 * @desc: GPIO to set to output
2516 * @value: initial output value of the GPIO
2517 *
2518 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
2519 * be called safely on it. The initial value of the output must be specified
2520 * as the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
2521 * account.
2522 *
2523 * Return 0 in case of success, else an error code.
2524 */
2525int gpiod_direction_output(struct gpio_desc *desc, int value)
2526{
2527 struct gpio_chip *gc;
2528 int ret;
2529
2530 VALIDATE_DESC(desc);
2531 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
2532 value = !value;
2533 else
2534 value = !!value;
2535
2536 /* GPIOs used for IRQs shall not be set as output */
2537 if (test_bit(FLAG_USED_AS_IRQ, &desc->flags)) {
2538 gpiod_err(desc,
2539 "%s: tried to set a GPIO tied to an IRQ as output\n",
2540 __func__);
2541 return -EIO;
2542 }
2543
2544 gc = desc->gdev->chip;
2545 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) {
2546 /* First see if we can enable open drain in hardware */
2547 ret = gpio_set_drive_single_ended(gc, gpio_chip_hwgpio(desc),
2548 PIN_CONFIG_DRIVE_OPEN_DRAIN);
2549 if (!ret)
2550 goto set_output_value;
2551 /* Emulate open drain by not actively driving the line high */
2552 if (value)
2553 return gpiod_direction_input(desc);
2554 }
2555 else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) {
2556 ret = gpio_set_drive_single_ended(gc, gpio_chip_hwgpio(desc),
2557 PIN_CONFIG_DRIVE_OPEN_SOURCE);
2558 if (!ret)
2559 goto set_output_value;
2560 /* Emulate open source by not actively driving the line low */
2561 if (!value)
2562 return gpiod_direction_input(desc);
2563 } else {
2564 gpio_set_drive_single_ended(gc, gpio_chip_hwgpio(desc),
2565 PIN_CONFIG_DRIVE_PUSH_PULL);
2566 }
2567
2568set_output_value:
2569 return gpiod_direction_output_raw_commit(desc, value);
2570}
2571EXPORT_SYMBOL_GPL(gpiod_direction_output);
2572
2573/**
2574 * gpiod_set_debounce - sets @debounce time for a GPIO
2575 * @desc: descriptor of the GPIO for which to set debounce time
2576 * @debounce: debounce time in microseconds
2577 *
2578 * Returns:
2579 * 0 on success, %-ENOTSUPP if the controller doesn't support setting the
2580 * debounce time.
2581 */
2582int gpiod_set_debounce(struct gpio_desc *desc, unsigned debounce)
2583{
2584 struct gpio_chip *chip;
2585 unsigned long config;
2586
2587 VALIDATE_DESC(desc);
2588 chip = desc->gdev->chip;
2589 if (!chip->set || !chip->set_config) {
2590 gpiod_dbg(desc,
2591 "%s: missing set() or set_config() operations\n",
2592 __func__);
2593 return -ENOTSUPP;
2594 }
2595
2596 config = pinconf_to_config_packed(PIN_CONFIG_INPUT_DEBOUNCE, debounce);
2597 return chip->set_config(chip, gpio_chip_hwgpio(desc), config);
2598}
2599EXPORT_SYMBOL_GPL(gpiod_set_debounce);
2600
2601/**
2602 * gpiod_set_transitory - Lose or retain GPIO state on suspend or reset
2603 * @desc: descriptor of the GPIO for which to configure persistence
2604 * @transitory: True to lose state on suspend or reset, false for persistence
2605 *
2606 * Returns:
2607 * 0 on success, otherwise a negative error code.
2608 */
2609int gpiod_set_transitory(struct gpio_desc *desc, bool transitory)
2610{
2611 struct gpio_chip *chip;
2612 unsigned long packed;
2613 int gpio;
2614 int rc;
2615
2616 VALIDATE_DESC(desc);
2617 /*
2618 * Handle FLAG_TRANSITORY first, enabling queries to gpiolib for
2619 * persistence state.
2620 */
2621 if (transitory)
2622 set_bit(FLAG_TRANSITORY, &desc->flags);
2623 else
2624 clear_bit(FLAG_TRANSITORY, &desc->flags);
2625
2626 /* If the driver supports it, set the persistence state now */
2627 chip = desc->gdev->chip;
2628 if (!chip->set_config)
2629 return 0;
2630
2631 packed = pinconf_to_config_packed(PIN_CONFIG_PERSIST_STATE,
2632 !transitory);
2633 gpio = gpio_chip_hwgpio(desc);
2634 rc = chip->set_config(chip, gpio, packed);
2635 if (rc == -ENOTSUPP) {
2636 dev_dbg(&desc->gdev->dev, "Persistence not supported for GPIO %d\n",
2637 gpio);
2638 return 0;
2639 }
2640
2641 return rc;
2642}
2643EXPORT_SYMBOL_GPL(gpiod_set_transitory);
2644
2645/**
2646 * gpiod_is_active_low - test whether a GPIO is active-low or not
2647 * @desc: the gpio descriptor to test
2648 *
2649 * Returns 1 if the GPIO is active-low, 0 otherwise.
2650 */
2651int gpiod_is_active_low(const struct gpio_desc *desc)
2652{
2653 VALIDATE_DESC(desc);
2654 return test_bit(FLAG_ACTIVE_LOW, &desc->flags);
2655}
2656EXPORT_SYMBOL_GPL(gpiod_is_active_low);
2657
2658/* I/O calls are only valid after configuration completed; the relevant
2659 * "is this a valid GPIO" error checks should already have been done.
2660 *
2661 * "Get" operations are often inlinable as reading a pin value register,
2662 * and masking the relevant bit in that register.
2663 *
2664 * When "set" operations are inlinable, they involve writing that mask to
2665 * one register to set a low value, or a different register to set it high.
2666 * Otherwise locking is needed, so there may be little value to inlining.
2667 *
2668 *------------------------------------------------------------------------
2669 *
2670 * IMPORTANT!!! The hot paths -- get/set value -- assume that callers
2671 * have requested the GPIO. That can include implicit requesting by
2672 * a direction setting call. Marking a gpio as requested locks its chip
2673 * in memory, guaranteeing that these table lookups need no more locking
2674 * and that gpiochip_remove() will fail.
2675 *
2676 * REVISIT when debugging, consider adding some instrumentation to ensure
2677 * that the GPIO was actually requested.
2678 */
2679
2680static int gpiod_get_raw_value_commit(const struct gpio_desc *desc)
2681{
2682 struct gpio_chip *chip;
2683 int offset;
2684 int value;
2685
2686 chip = desc->gdev->chip;
2687 offset = gpio_chip_hwgpio(desc);
2688 value = chip->get ? chip->get(chip, offset) : -EIO;
2689 value = value < 0 ? value : !!value;
2690 trace_gpio_value(desc_to_gpio(desc), 1, value);
2691 return value;
2692}
2693
2694static int gpio_chip_get_multiple(struct gpio_chip *chip,
2695 unsigned long *mask, unsigned long *bits)
2696{
2697 if (chip->get_multiple) {
2698 return chip->get_multiple(chip, mask, bits);
2699 } else if (chip->get) {
2700 int i, value;
2701
2702 for_each_set_bit(i, mask, chip->ngpio) {
2703 value = chip->get(chip, i);
2704 if (value < 0)
2705 return value;
2706 __assign_bit(i, bits, value);
2707 }
2708 return 0;
2709 }
2710 return -EIO;
2711}
2712
2713int gpiod_get_array_value_complex(bool raw, bool can_sleep,
2714 unsigned int array_size,
2715 struct gpio_desc **desc_array,
2716 int *value_array)
2717{
2718 int i = 0;
2719
2720 while (i < array_size) {
2721 struct gpio_chip *chip = desc_array[i]->gdev->chip;
2722 unsigned long mask[BITS_TO_LONGS(chip->ngpio)];
2723 unsigned long bits[BITS_TO_LONGS(chip->ngpio)];
2724 int first, j, ret;
2725
2726 if (!can_sleep)
2727 WARN_ON(chip->can_sleep);
2728
2729 /* collect all inputs belonging to the same chip */
2730 first = i;
2731 memset(mask, 0, sizeof(mask));
2732 do {
2733 const struct gpio_desc *desc = desc_array[i];
2734 int hwgpio = gpio_chip_hwgpio(desc);
2735
2736 __set_bit(hwgpio, mask);
2737 i++;
2738 } while ((i < array_size) &&
2739 (desc_array[i]->gdev->chip == chip));
2740
2741 ret = gpio_chip_get_multiple(chip, mask, bits);
2742 if (ret)
2743 return ret;
2744
2745 for (j = first; j < i; j++) {
2746 const struct gpio_desc *desc = desc_array[j];
2747 int hwgpio = gpio_chip_hwgpio(desc);
2748 int value = test_bit(hwgpio, bits);
2749
2750 if (!raw && test_bit(FLAG_ACTIVE_LOW, &desc->flags))
2751 value = !value;
2752 value_array[j] = value;
2753 trace_gpio_value(desc_to_gpio(desc), 1, value);
2754 }
2755 }
2756 return 0;
2757}
2758
2759/**
2760 * gpiod_get_raw_value() - return a gpio's raw value
2761 * @desc: gpio whose value will be returned
2762 *
2763 * Return the GPIO's raw value, i.e. the value of the physical line disregarding
2764 * its ACTIVE_LOW status, or negative errno on failure.
2765 *
2766 * This function should be called from contexts where we cannot sleep, and will
2767 * complain if the GPIO chip functions potentially sleep.
2768 */
2769int gpiod_get_raw_value(const struct gpio_desc *desc)
2770{
2771 VALIDATE_DESC(desc);
2772 /* Should be using gpio_get_value_cansleep() */
2773 WARN_ON(desc->gdev->chip->can_sleep);
2774 return gpiod_get_raw_value_commit(desc);
2775}
2776EXPORT_SYMBOL_GPL(gpiod_get_raw_value);
2777
2778/**
2779 * gpiod_get_value() - return a gpio's value
2780 * @desc: gpio whose value will be returned
2781 *
2782 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
2783 * account, or negative errno on failure.
2784 *
2785 * This function should be called from contexts where we cannot sleep, and will
2786 * complain if the GPIO chip functions potentially sleep.
2787 */
2788int gpiod_get_value(const struct gpio_desc *desc)
2789{
2790 int value;
2791
2792 VALIDATE_DESC(desc);
2793 /* Should be using gpio_get_value_cansleep() */
2794 WARN_ON(desc->gdev->chip->can_sleep);
2795
2796 value = gpiod_get_raw_value_commit(desc);
2797 if (value < 0)
2798 return value;
2799
2800 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
2801 value = !value;
2802
2803 return value;
2804}
2805EXPORT_SYMBOL_GPL(gpiod_get_value);
2806
2807/**
2808 * gpiod_get_raw_array_value() - read raw values from an array of GPIOs
2809 * @array_size: number of elements in the descriptor / value arrays
2810 * @desc_array: array of GPIO descriptors whose values will be read
2811 * @value_array: array to store the read values
2812 *
2813 * Read the raw values of the GPIOs, i.e. the values of the physical lines
2814 * without regard for their ACTIVE_LOW status. Return 0 in case of success,
2815 * else an error code.
2816 *
2817 * This function should be called from contexts where we cannot sleep,
2818 * and it will complain if the GPIO chip functions potentially sleep.
2819 */
2820int gpiod_get_raw_array_value(unsigned int array_size,
2821 struct gpio_desc **desc_array, int *value_array)
2822{
2823 if (!desc_array)
2824 return -EINVAL;
2825 return gpiod_get_array_value_complex(true, false, array_size,
2826 desc_array, value_array);
2827}
2828EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value);
2829
2830/**
2831 * gpiod_get_array_value() - read values from an array of GPIOs
2832 * @array_size: number of elements in the descriptor / value arrays
2833 * @desc_array: array of GPIO descriptors whose values will be read
2834 * @value_array: array to store the read values
2835 *
2836 * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
2837 * into account. Return 0 in case of success, else an error code.
2838 *
2839 * This function should be called from contexts where we cannot sleep,
2840 * and it will complain if the GPIO chip functions potentially sleep.
2841 */
2842int gpiod_get_array_value(unsigned int array_size,
2843 struct gpio_desc **desc_array, int *value_array)
2844{
2845 if (!desc_array)
2846 return -EINVAL;
2847 return gpiod_get_array_value_complex(false, false, array_size,
2848 desc_array, value_array);
2849}
2850EXPORT_SYMBOL_GPL(gpiod_get_array_value);
2851
2852/*
2853 * gpio_set_open_drain_value_commit() - Set the open drain gpio's value.
2854 * @desc: gpio descriptor whose state need to be set.
2855 * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
2856 */
2857static void gpio_set_open_drain_value_commit(struct gpio_desc *desc, bool value)
2858{
2859 int err = 0;
2860 struct gpio_chip *chip = desc->gdev->chip;
2861 int offset = gpio_chip_hwgpio(desc);
2862
2863 if (value) {
2864 err = chip->direction_input(chip, offset);
2865 if (!err)
2866 clear_bit(FLAG_IS_OUT, &desc->flags);
2867 } else {
2868 err = chip->direction_output(chip, offset, 0);
2869 if (!err)
2870 set_bit(FLAG_IS_OUT, &desc->flags);
2871 }
2872 trace_gpio_direction(desc_to_gpio(desc), value, err);
2873 if (err < 0)
2874 gpiod_err(desc,
2875 "%s: Error in set_value for open drain err %d\n",
2876 __func__, err);
2877}
2878
2879/*
2880 * _gpio_set_open_source_value() - Set the open source gpio's value.
2881 * @desc: gpio descriptor whose state need to be set.
2882 * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
2883 */
2884static void gpio_set_open_source_value_commit(struct gpio_desc *desc, bool value)
2885{
2886 int err = 0;
2887 struct gpio_chip *chip = desc->gdev->chip;
2888 int offset = gpio_chip_hwgpio(desc);
2889
2890 if (value) {
2891 err = chip->direction_output(chip, offset, 1);
2892 if (!err)
2893 set_bit(FLAG_IS_OUT, &desc->flags);
2894 } else {
2895 err = chip->direction_input(chip, offset);
2896 if (!err)
2897 clear_bit(FLAG_IS_OUT, &desc->flags);
2898 }
2899 trace_gpio_direction(desc_to_gpio(desc), !value, err);
2900 if (err < 0)
2901 gpiod_err(desc,
2902 "%s: Error in set_value for open source err %d\n",
2903 __func__, err);
2904}
2905
2906static void gpiod_set_raw_value_commit(struct gpio_desc *desc, bool value)
2907{
2908 struct gpio_chip *chip;
2909
2910 chip = desc->gdev->chip;
2911 trace_gpio_value(desc_to_gpio(desc), 0, value);
2912 chip->set(chip, gpio_chip_hwgpio(desc), value);
2913}
2914
2915/*
2916 * set multiple outputs on the same chip;
2917 * use the chip's set_multiple function if available;
2918 * otherwise set the outputs sequentially;
2919 * @mask: bit mask array; one bit per output; BITS_PER_LONG bits per word
2920 * defines which outputs are to be changed
2921 * @bits: bit value array; one bit per output; BITS_PER_LONG bits per word
2922 * defines the values the outputs specified by mask are to be set to
2923 */
2924static void gpio_chip_set_multiple(struct gpio_chip *chip,
2925 unsigned long *mask, unsigned long *bits)
2926{
2927 if (chip->set_multiple) {
2928 chip->set_multiple(chip, mask, bits);
2929 } else {
2930 unsigned int i;
2931
2932 /* set outputs if the corresponding mask bit is set */
2933 for_each_set_bit(i, mask, chip->ngpio)
2934 chip->set(chip, i, test_bit(i, bits));
2935 }
2936}
2937
2938void gpiod_set_array_value_complex(bool raw, bool can_sleep,
2939 unsigned int array_size,
2940 struct gpio_desc **desc_array,
2941 int *value_array)
2942{
2943 int i = 0;
2944
2945 while (i < array_size) {
2946 struct gpio_chip *chip = desc_array[i]->gdev->chip;
2947 unsigned long mask[BITS_TO_LONGS(chip->ngpio)];
2948 unsigned long bits[BITS_TO_LONGS(chip->ngpio)];
2949 int count = 0;
2950
2951 if (!can_sleep)
2952 WARN_ON(chip->can_sleep);
2953
2954 memset(mask, 0, sizeof(mask));
2955 do {
2956 struct gpio_desc *desc = desc_array[i];
2957 int hwgpio = gpio_chip_hwgpio(desc);
2958 int value = value_array[i];
2959
2960 if (!raw && test_bit(FLAG_ACTIVE_LOW, &desc->flags))
2961 value = !value;
2962 trace_gpio_value(desc_to_gpio(desc), 0, value);
2963 /*
2964 * collect all normal outputs belonging to the same chip
2965 * open drain and open source outputs are set individually
2966 */
2967 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags) && !raw) {
2968 gpio_set_open_drain_value_commit(desc, value);
2969 } else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags) && !raw) {
2970 gpio_set_open_source_value_commit(desc, value);
2971 } else {
2972 __set_bit(hwgpio, mask);
2973 if (value)
2974 __set_bit(hwgpio, bits);
2975 else
2976 __clear_bit(hwgpio, bits);
2977 count++;
2978 }
2979 i++;
2980 } while ((i < array_size) &&
2981 (desc_array[i]->gdev->chip == chip));
2982 /* push collected bits to outputs */
2983 if (count != 0)
2984 gpio_chip_set_multiple(chip, mask, bits);
2985 }
2986}
2987
2988/**
2989 * gpiod_set_raw_value() - assign a gpio's raw value
2990 * @desc: gpio whose value will be assigned
2991 * @value: value to assign
2992 *
2993 * Set the raw value of the GPIO, i.e. the value of its physical line without
2994 * regard for its ACTIVE_LOW status.
2995 *
2996 * This function should be called from contexts where we cannot sleep, and will
2997 * complain if the GPIO chip functions potentially sleep.
2998 */
2999void gpiod_set_raw_value(struct gpio_desc *desc, int value)
3000{
3001 VALIDATE_DESC_VOID(desc);
3002 /* Should be using gpiod_set_value_cansleep() */
3003 WARN_ON(desc->gdev->chip->can_sleep);
3004 gpiod_set_raw_value_commit(desc, value);
3005}
3006EXPORT_SYMBOL_GPL(gpiod_set_raw_value);
3007
3008/**
3009 * gpiod_set_value_nocheck() - set a GPIO line value without checking
3010 * @desc: the descriptor to set the value on
3011 * @value: value to set
3012 *
3013 * This sets the value of a GPIO line backing a descriptor, applying
3014 * different semantic quirks like active low and open drain/source
3015 * handling.
3016 */
3017static void gpiod_set_value_nocheck(struct gpio_desc *desc, int value)
3018{
3019 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3020 value = !value;
3021 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags))
3022 gpio_set_open_drain_value_commit(desc, value);
3023 else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags))
3024 gpio_set_open_source_value_commit(desc, value);
3025 else
3026 gpiod_set_raw_value_commit(desc, value);
3027}
3028
3029/**
3030 * gpiod_set_value() - assign a gpio's value
3031 * @desc: gpio whose value will be assigned
3032 * @value: value to assign
3033 *
3034 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW,
3035 * OPEN_DRAIN and OPEN_SOURCE flags into account.
3036 *
3037 * This function should be called from contexts where we cannot sleep, and will
3038 * complain if the GPIO chip functions potentially sleep.
3039 */
3040void gpiod_set_value(struct gpio_desc *desc, int value)
3041{
3042 VALIDATE_DESC_VOID(desc);
3043 WARN_ON(desc->gdev->chip->can_sleep);
3044 gpiod_set_value_nocheck(desc, value);
3045}
3046EXPORT_SYMBOL_GPL(gpiod_set_value);
3047
3048/**
3049 * gpiod_set_raw_array_value() - assign values to an array of GPIOs
3050 * @array_size: number of elements in the descriptor / value arrays
3051 * @desc_array: array of GPIO descriptors whose values will be assigned
3052 * @value_array: array of values to assign
3053 *
3054 * Set the raw values of the GPIOs, i.e. the values of the physical lines
3055 * without regard for their ACTIVE_LOW status.
3056 *
3057 * This function should be called from contexts where we cannot sleep, and will
3058 * complain if the GPIO chip functions potentially sleep.
3059 */
3060void gpiod_set_raw_array_value(unsigned int array_size,
3061 struct gpio_desc **desc_array, int *value_array)
3062{
3063 if (!desc_array)
3064 return;
3065 gpiod_set_array_value_complex(true, false, array_size, desc_array,
3066 value_array);
3067}
3068EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value);
3069
3070/**
3071 * gpiod_set_array_value() - assign values to an array of GPIOs
3072 * @array_size: number of elements in the descriptor / value arrays
3073 * @desc_array: array of GPIO descriptors whose values will be assigned
3074 * @value_array: array of values to assign
3075 *
3076 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3077 * into account.
3078 *
3079 * This function should be called from contexts where we cannot sleep, and will
3080 * complain if the GPIO chip functions potentially sleep.
3081 */
3082void gpiod_set_array_value(unsigned int array_size,
3083 struct gpio_desc **desc_array, int *value_array)
3084{
3085 if (!desc_array)
3086 return;
3087 gpiod_set_array_value_complex(false, false, array_size, desc_array,
3088 value_array);
3089}
3090EXPORT_SYMBOL_GPL(gpiod_set_array_value);
3091
3092/**
3093 * gpiod_cansleep() - report whether gpio value access may sleep
3094 * @desc: gpio to check
3095 *
3096 */
3097int gpiod_cansleep(const struct gpio_desc *desc)
3098{
3099 VALIDATE_DESC(desc);
3100 return desc->gdev->chip->can_sleep;
3101}
3102EXPORT_SYMBOL_GPL(gpiod_cansleep);
3103
3104/**
3105 * gpiod_to_irq() - return the IRQ corresponding to a GPIO
3106 * @desc: gpio whose IRQ will be returned (already requested)
3107 *
3108 * Return the IRQ corresponding to the passed GPIO, or an error code in case of
3109 * error.
3110 */
3111int gpiod_to_irq(const struct gpio_desc *desc)
3112{
3113 struct gpio_chip *chip;
3114 int offset;
3115
3116 /*
3117 * Cannot VALIDATE_DESC() here as gpiod_to_irq() consumer semantics
3118 * requires this function to not return zero on an invalid descriptor
3119 * but rather a negative error number.
3120 */
3121 if (!desc || IS_ERR(desc) || !desc->gdev || !desc->gdev->chip)
3122 return -EINVAL;
3123
3124 chip = desc->gdev->chip;
3125 offset = gpio_chip_hwgpio(desc);
3126 if (chip->to_irq) {
3127 int retirq = chip->to_irq(chip, offset);
3128
3129 /* Zero means NO_IRQ */
3130 if (!retirq)
3131 return -ENXIO;
3132
3133 return retirq;
3134 }
3135 return -ENXIO;
3136}
3137EXPORT_SYMBOL_GPL(gpiod_to_irq);
3138
3139/**
3140 * gpiochip_lock_as_irq() - lock a GPIO to be used as IRQ
3141 * @chip: the chip the GPIO to lock belongs to
3142 * @offset: the offset of the GPIO to lock as IRQ
3143 *
3144 * This is used directly by GPIO drivers that want to lock down
3145 * a certain GPIO line to be used for IRQs.
3146 */
3147int gpiochip_lock_as_irq(struct gpio_chip *chip, unsigned int offset)
3148{
3149 struct gpio_desc *desc;
3150
3151 desc = gpiochip_get_desc(chip, offset);
3152 if (IS_ERR(desc))
3153 return PTR_ERR(desc);
3154
3155 /*
3156 * If it's fast: flush the direction setting if something changed
3157 * behind our back
3158 */
3159 if (!chip->can_sleep && chip->get_direction) {
3160 int dir = chip->get_direction(chip, offset);
3161
3162 if (dir)
3163 clear_bit(FLAG_IS_OUT, &desc->flags);
3164 else
3165 set_bit(FLAG_IS_OUT, &desc->flags);
3166 }
3167
3168 if (test_bit(FLAG_IS_OUT, &desc->flags)) {
3169 chip_err(chip,
3170 "%s: tried to flag a GPIO set as output for IRQ\n",
3171 __func__);
3172 return -EIO;
3173 }
3174
3175 set_bit(FLAG_USED_AS_IRQ, &desc->flags);
3176
3177 /*
3178 * If the consumer has not set up a label (such as when the
3179 * IRQ is referenced from .to_irq()) we set up a label here
3180 * so it is clear this is used as an interrupt.
3181 */
3182 if (!desc->label)
3183 desc_set_label(desc, "interrupt");
3184
3185 return 0;
3186}
3187EXPORT_SYMBOL_GPL(gpiochip_lock_as_irq);
3188
3189/**
3190 * gpiochip_unlock_as_irq() - unlock a GPIO used as IRQ
3191 * @chip: the chip the GPIO to lock belongs to
3192 * @offset: the offset of the GPIO to lock as IRQ
3193 *
3194 * This is used directly by GPIO drivers that want to indicate
3195 * that a certain GPIO is no longer used exclusively for IRQ.
3196 */
3197void gpiochip_unlock_as_irq(struct gpio_chip *chip, unsigned int offset)
3198{
3199 struct gpio_desc *desc;
3200
3201 desc = gpiochip_get_desc(chip, offset);
3202 if (IS_ERR(desc))
3203 return;
3204
3205 clear_bit(FLAG_USED_AS_IRQ, &desc->flags);
3206
3207 /* If we only had this marking, erase it */
3208 if (desc->label && !strcmp(desc->label, "interrupt"))
3209 desc_set_label(desc, NULL);
3210}
3211EXPORT_SYMBOL_GPL(gpiochip_unlock_as_irq);
3212
3213bool gpiochip_line_is_irq(struct gpio_chip *chip, unsigned int offset)
3214{
3215 if (offset >= chip->ngpio)
3216 return false;
3217
3218 return test_bit(FLAG_USED_AS_IRQ, &chip->gpiodev->descs[offset].flags);
3219}
3220EXPORT_SYMBOL_GPL(gpiochip_line_is_irq);
3221
3222bool gpiochip_line_is_open_drain(struct gpio_chip *chip, unsigned int offset)
3223{
3224 if (offset >= chip->ngpio)
3225 return false;
3226
3227 return test_bit(FLAG_OPEN_DRAIN, &chip->gpiodev->descs[offset].flags);
3228}
3229EXPORT_SYMBOL_GPL(gpiochip_line_is_open_drain);
3230
3231bool gpiochip_line_is_open_source(struct gpio_chip *chip, unsigned int offset)
3232{
3233 if (offset >= chip->ngpio)
3234 return false;
3235
3236 return test_bit(FLAG_OPEN_SOURCE, &chip->gpiodev->descs[offset].flags);
3237}
3238EXPORT_SYMBOL_GPL(gpiochip_line_is_open_source);
3239
3240bool gpiochip_line_is_persistent(struct gpio_chip *chip, unsigned int offset)
3241{
3242 if (offset >= chip->ngpio)
3243 return false;
3244
3245 return !test_bit(FLAG_TRANSITORY, &chip->gpiodev->descs[offset].flags);
3246}
3247EXPORT_SYMBOL_GPL(gpiochip_line_is_persistent);
3248
3249/**
3250 * gpiod_get_raw_value_cansleep() - return a gpio's raw value
3251 * @desc: gpio whose value will be returned
3252 *
3253 * Return the GPIO's raw value, i.e. the value of the physical line disregarding
3254 * its ACTIVE_LOW status, or negative errno on failure.
3255 *
3256 * This function is to be called from contexts that can sleep.
3257 */
3258int gpiod_get_raw_value_cansleep(const struct gpio_desc *desc)
3259{
3260 might_sleep_if(extra_checks);
3261 VALIDATE_DESC(desc);
3262 return gpiod_get_raw_value_commit(desc);
3263}
3264EXPORT_SYMBOL_GPL(gpiod_get_raw_value_cansleep);
3265
3266/**
3267 * gpiod_get_value_cansleep() - return a gpio's value
3268 * @desc: gpio whose value will be returned
3269 *
3270 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
3271 * account, or negative errno on failure.
3272 *
3273 * This function is to be called from contexts that can sleep.
3274 */
3275int gpiod_get_value_cansleep(const struct gpio_desc *desc)
3276{
3277 int value;
3278
3279 might_sleep_if(extra_checks);
3280 VALIDATE_DESC(desc);
3281 value = gpiod_get_raw_value_commit(desc);
3282 if (value < 0)
3283 return value;
3284
3285 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3286 value = !value;
3287
3288 return value;
3289}
3290EXPORT_SYMBOL_GPL(gpiod_get_value_cansleep);
3291
3292/**
3293 * gpiod_get_raw_array_value_cansleep() - read raw values from an array of GPIOs
3294 * @array_size: number of elements in the descriptor / value arrays
3295 * @desc_array: array of GPIO descriptors whose values will be read
3296 * @value_array: array to store the read values
3297 *
3298 * Read the raw values of the GPIOs, i.e. the values of the physical lines
3299 * without regard for their ACTIVE_LOW status. Return 0 in case of success,
3300 * else an error code.
3301 *
3302 * This function is to be called from contexts that can sleep.
3303 */
3304int gpiod_get_raw_array_value_cansleep(unsigned int array_size,
3305 struct gpio_desc **desc_array,
3306 int *value_array)
3307{
3308 might_sleep_if(extra_checks);
3309 if (!desc_array)
3310 return -EINVAL;
3311 return gpiod_get_array_value_complex(true, true, array_size,
3312 desc_array, value_array);
3313}
3314EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value_cansleep);
3315
3316/**
3317 * gpiod_get_array_value_cansleep() - read values from an array of GPIOs
3318 * @array_size: number of elements in the descriptor / value arrays
3319 * @desc_array: array of GPIO descriptors whose values will be read
3320 * @value_array: array to store the read values
3321 *
3322 * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3323 * into account. Return 0 in case of success, else an error code.
3324 *
3325 * This function is to be called from contexts that can sleep.
3326 */
3327int gpiod_get_array_value_cansleep(unsigned int array_size,
3328 struct gpio_desc **desc_array,
3329 int *value_array)
3330{
3331 might_sleep_if(extra_checks);
3332 if (!desc_array)
3333 return -EINVAL;
3334 return gpiod_get_array_value_complex(false, true, array_size,
3335 desc_array, value_array);
3336}
3337EXPORT_SYMBOL_GPL(gpiod_get_array_value_cansleep);
3338
3339/**
3340 * gpiod_set_raw_value_cansleep() - assign a gpio's raw value
3341 * @desc: gpio whose value will be assigned
3342 * @value: value to assign
3343 *
3344 * Set the raw value of the GPIO, i.e. the value of its physical line without
3345 * regard for its ACTIVE_LOW status.
3346 *
3347 * This function is to be called from contexts that can sleep.
3348 */
3349void gpiod_set_raw_value_cansleep(struct gpio_desc *desc, int value)
3350{
3351 might_sleep_if(extra_checks);
3352 VALIDATE_DESC_VOID(desc);
3353 gpiod_set_raw_value_commit(desc, value);
3354}
3355EXPORT_SYMBOL_GPL(gpiod_set_raw_value_cansleep);
3356
3357/**
3358 * gpiod_set_value_cansleep() - assign a gpio's value
3359 * @desc: gpio whose value will be assigned
3360 * @value: value to assign
3361 *
3362 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
3363 * account
3364 *
3365 * This function is to be called from contexts that can sleep.
3366 */
3367void gpiod_set_value_cansleep(struct gpio_desc *desc, int value)
3368{
3369 might_sleep_if(extra_checks);
3370 VALIDATE_DESC_VOID(desc);
3371 gpiod_set_value_nocheck(desc, value);
3372}
3373EXPORT_SYMBOL_GPL(gpiod_set_value_cansleep);
3374
3375/**
3376 * gpiod_set_raw_array_value_cansleep() - assign values to an array of GPIOs
3377 * @array_size: number of elements in the descriptor / value arrays
3378 * @desc_array: array of GPIO descriptors whose values will be assigned
3379 * @value_array: array of values to assign
3380 *
3381 * Set the raw values of the GPIOs, i.e. the values of the physical lines
3382 * without regard for their ACTIVE_LOW status.
3383 *
3384 * This function is to be called from contexts that can sleep.
3385 */
3386void gpiod_set_raw_array_value_cansleep(unsigned int array_size,
3387 struct gpio_desc **desc_array,
3388 int *value_array)
3389{
3390 might_sleep_if(extra_checks);
3391 if (!desc_array)
3392 return;
3393 gpiod_set_array_value_complex(true, true, array_size, desc_array,
3394 value_array);
3395}
3396EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value_cansleep);
3397
3398/**
3399 * gpiod_add_lookup_tables() - register GPIO device consumers
3400 * @tables: list of tables of consumers to register
3401 * @n: number of tables in the list
3402 */
3403void gpiod_add_lookup_tables(struct gpiod_lookup_table **tables, size_t n)
3404{
3405 unsigned int i;
3406
3407 mutex_lock(&gpio_lookup_lock);
3408
3409 for (i = 0; i < n; i++)
3410 list_add_tail(&tables[i]->list, &gpio_lookup_list);
3411
3412 mutex_unlock(&gpio_lookup_lock);
3413}
3414
3415/**
3416 * gpiod_set_array_value_cansleep() - assign values to an array of GPIOs
3417 * @array_size: number of elements in the descriptor / value arrays
3418 * @desc_array: array of GPIO descriptors whose values will be assigned
3419 * @value_array: array of values to assign
3420 *
3421 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3422 * into account.
3423 *
3424 * This function is to be called from contexts that can sleep.
3425 */
3426void gpiod_set_array_value_cansleep(unsigned int array_size,
3427 struct gpio_desc **desc_array,
3428 int *value_array)
3429{
3430 might_sleep_if(extra_checks);
3431 if (!desc_array)
3432 return;
3433 gpiod_set_array_value_complex(false, true, array_size, desc_array,
3434 value_array);
3435}
3436EXPORT_SYMBOL_GPL(gpiod_set_array_value_cansleep);
3437
3438/**
3439 * gpiod_add_lookup_table() - register GPIO device consumers
3440 * @table: table of consumers to register
3441 */
3442void gpiod_add_lookup_table(struct gpiod_lookup_table *table)
3443{
3444 mutex_lock(&gpio_lookup_lock);
3445
3446 list_add_tail(&table->list, &gpio_lookup_list);
3447
3448 mutex_unlock(&gpio_lookup_lock);
3449}
3450EXPORT_SYMBOL_GPL(gpiod_add_lookup_table);
3451
3452/**
3453 * gpiod_remove_lookup_table() - unregister GPIO device consumers
3454 * @table: table of consumers to unregister
3455 */
3456void gpiod_remove_lookup_table(struct gpiod_lookup_table *table)
3457{
3458 mutex_lock(&gpio_lookup_lock);
3459
3460 list_del(&table->list);
3461
3462 mutex_unlock(&gpio_lookup_lock);
3463}
3464EXPORT_SYMBOL_GPL(gpiod_remove_lookup_table);
3465
3466static struct gpiod_lookup_table *gpiod_find_lookup_table(struct device *dev)
3467{
3468 const char *dev_id = dev ? dev_name(dev) : NULL;
3469 struct gpiod_lookup_table *table;
3470
3471 mutex_lock(&gpio_lookup_lock);
3472
3473 list_for_each_entry(table, &gpio_lookup_list, list) {
3474 if (table->dev_id && dev_id) {
3475 /*
3476 * Valid strings on both ends, must be identical to have
3477 * a match
3478 */
3479 if (!strcmp(table->dev_id, dev_id))
3480 goto found;
3481 } else {
3482 /*
3483 * One of the pointers is NULL, so both must be to have
3484 * a match
3485 */
3486 if (dev_id == table->dev_id)
3487 goto found;
3488 }
3489 }
3490 table = NULL;
3491
3492found:
3493 mutex_unlock(&gpio_lookup_lock);
3494 return table;
3495}
3496
3497static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id,
3498 unsigned int idx,
3499 enum gpio_lookup_flags *flags)
3500{
3501 struct gpio_desc *desc = ERR_PTR(-ENOENT);
3502 struct gpiod_lookup_table *table;
3503 struct gpiod_lookup *p;
3504
3505 table = gpiod_find_lookup_table(dev);
3506 if (!table)
3507 return desc;
3508
3509 for (p = &table->table[0]; p->chip_label; p++) {
3510 struct gpio_chip *chip;
3511
3512 /* idx must always match exactly */
3513 if (p->idx != idx)
3514 continue;
3515
3516 /* If the lookup entry has a con_id, require exact match */
3517 if (p->con_id && (!con_id || strcmp(p->con_id, con_id)))
3518 continue;
3519
3520 chip = find_chip_by_name(p->chip_label);
3521
3522 if (!chip) {
3523 dev_err(dev, "cannot find GPIO chip %s\n",
3524 p->chip_label);
3525 return ERR_PTR(-ENODEV);
3526 }
3527
3528 if (chip->ngpio <= p->chip_hwnum) {
3529 dev_err(dev,
3530 "requested GPIO %d is out of range [0..%d] for chip %s\n",
3531 idx, chip->ngpio, chip->label);
3532 return ERR_PTR(-EINVAL);
3533 }
3534
3535 desc = gpiochip_get_desc(chip, p->chip_hwnum);
3536 *flags = p->flags;
3537
3538 return desc;
3539 }
3540
3541 return desc;
3542}
3543
3544static int dt_gpio_count(struct device *dev, const char *con_id)
3545{
3546 int ret;
3547 char propname[32];
3548 unsigned int i;
3549
3550 for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
3551 if (con_id)
3552 snprintf(propname, sizeof(propname), "%s-%s",
3553 con_id, gpio_suffixes[i]);
3554 else
3555 snprintf(propname, sizeof(propname), "%s",
3556 gpio_suffixes[i]);
3557
3558 ret = of_gpio_named_count(dev->of_node, propname);
3559 if (ret > 0)
3560 break;
3561 }
3562 return ret ? ret : -ENOENT;
3563}
3564
3565static int platform_gpio_count(struct device *dev, const char *con_id)
3566{
3567 struct gpiod_lookup_table *table;
3568 struct gpiod_lookup *p;
3569 unsigned int count = 0;
3570
3571 table = gpiod_find_lookup_table(dev);
3572 if (!table)
3573 return -ENOENT;
3574
3575 for (p = &table->table[0]; p->chip_label; p++) {
3576 if ((con_id && p->con_id && !strcmp(con_id, p->con_id)) ||
3577 (!con_id && !p->con_id))
3578 count++;
3579 }
3580 if (!count)
3581 return -ENOENT;
3582
3583 return count;
3584}
3585
3586/**
3587 * gpiod_count - return the number of GPIOs associated with a device / function
3588 * or -ENOENT if no GPIO has been assigned to the requested function
3589 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3590 * @con_id: function within the GPIO consumer
3591 */
3592int gpiod_count(struct device *dev, const char *con_id)
3593{
3594 int count = -ENOENT;
3595
3596 if (IS_ENABLED(CONFIG_OF) && dev && dev->of_node)
3597 count = dt_gpio_count(dev, con_id);
3598 else if (IS_ENABLED(CONFIG_ACPI) && dev && ACPI_HANDLE(dev))
3599 count = acpi_gpio_count(dev, con_id);
3600
3601 if (count < 0)
3602 count = platform_gpio_count(dev, con_id);
3603
3604 return count;
3605}
3606EXPORT_SYMBOL_GPL(gpiod_count);
3607
3608/**
3609 * gpiod_get - obtain a GPIO for a given GPIO function
3610 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3611 * @con_id: function within the GPIO consumer
3612 * @flags: optional GPIO initialization flags
3613 *
3614 * Return the GPIO descriptor corresponding to the function con_id of device
3615 * dev, -ENOENT if no GPIO has been assigned to the requested function, or
3616 * another IS_ERR() code if an error occurred while trying to acquire the GPIO.
3617 */
3618struct gpio_desc *__must_check gpiod_get(struct device *dev, const char *con_id,
3619 enum gpiod_flags flags)
3620{
3621 return gpiod_get_index(dev, con_id, 0, flags);
3622}
3623EXPORT_SYMBOL_GPL(gpiod_get);
3624
3625/**
3626 * gpiod_get_optional - obtain an optional GPIO for a given GPIO function
3627 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3628 * @con_id: function within the GPIO consumer
3629 * @flags: optional GPIO initialization flags
3630 *
3631 * This is equivalent to gpiod_get(), except that when no GPIO was assigned to
3632 * the requested function it will return NULL. This is convenient for drivers
3633 * that need to handle optional GPIOs.
3634 */
3635struct gpio_desc *__must_check gpiod_get_optional(struct device *dev,
3636 const char *con_id,
3637 enum gpiod_flags flags)
3638{
3639 return gpiod_get_index_optional(dev, con_id, 0, flags);
3640}
3641EXPORT_SYMBOL_GPL(gpiod_get_optional);
3642
3643
3644/**
3645 * gpiod_configure_flags - helper function to configure a given GPIO
3646 * @desc: gpio whose value will be assigned
3647 * @con_id: function within the GPIO consumer
3648 * @lflags: gpio_lookup_flags - returned from of_find_gpio() or
3649 * of_get_gpio_hog()
3650 * @dflags: gpiod_flags - optional GPIO initialization flags
3651 *
3652 * Return 0 on success, -ENOENT if no GPIO has been assigned to the
3653 * requested function and/or index, or another IS_ERR() code if an error
3654 * occurred while trying to acquire the GPIO.
3655 */
3656int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id,
3657 unsigned long lflags, enum gpiod_flags dflags)
3658{
3659 int status;
3660
3661 if (lflags & GPIO_ACTIVE_LOW)
3662 set_bit(FLAG_ACTIVE_LOW, &desc->flags);
3663
3664 if (lflags & GPIO_OPEN_DRAIN)
3665 set_bit(FLAG_OPEN_DRAIN, &desc->flags);
3666 else if (dflags & GPIOD_FLAGS_BIT_OPEN_DRAIN) {
3667 /*
3668 * This enforces open drain mode from the consumer side.
3669 * This is necessary for some busses like I2C, but the lookup
3670 * should *REALLY* have specified them as open drain in the
3671 * first place, so print a little warning here.
3672 */
3673 set_bit(FLAG_OPEN_DRAIN, &desc->flags);
3674 gpiod_warn(desc,
3675 "enforced open drain please flag it properly in DT/ACPI DSDT/board file\n");
3676 }
3677
3678 if (lflags & GPIO_OPEN_SOURCE)
3679 set_bit(FLAG_OPEN_SOURCE, &desc->flags);
3680
3681 status = gpiod_set_transitory(desc, (lflags & GPIO_TRANSITORY));
3682 if (status < 0)
3683 return status;
3684
3685 /* No particular flag request, return here... */
3686 if (!(dflags & GPIOD_FLAGS_BIT_DIR_SET)) {
3687 pr_debug("no flags found for %s\n", con_id);
3688 return 0;
3689 }
3690
3691 /* Process flags */
3692 if (dflags & GPIOD_FLAGS_BIT_DIR_OUT)
3693 status = gpiod_direction_output(desc,
3694 !!(dflags & GPIOD_FLAGS_BIT_DIR_VAL));
3695 else
3696 status = gpiod_direction_input(desc);
3697
3698 return status;
3699}
3700
3701/**
3702 * gpiod_get_index - obtain a GPIO from a multi-index GPIO function
3703 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3704 * @con_id: function within the GPIO consumer
3705 * @idx: index of the GPIO to obtain in the consumer
3706 * @flags: optional GPIO initialization flags
3707 *
3708 * This variant of gpiod_get() allows to access GPIOs other than the first
3709 * defined one for functions that define several GPIOs.
3710 *
3711 * Return a valid GPIO descriptor, -ENOENT if no GPIO has been assigned to the
3712 * requested function and/or index, or another IS_ERR() code if an error
3713 * occurred while trying to acquire the GPIO.
3714 */
3715struct gpio_desc *__must_check gpiod_get_index(struct device *dev,
3716 const char *con_id,
3717 unsigned int idx,
3718 enum gpiod_flags flags)
3719{
3720 struct gpio_desc *desc = NULL;
3721 int status;
3722 enum gpio_lookup_flags lookupflags = 0;
3723 /* Maybe we have a device name, maybe not */
3724 const char *devname = dev ? dev_name(dev) : "?";
3725
3726 dev_dbg(dev, "GPIO lookup for consumer %s\n", con_id);
3727
3728 if (dev) {
3729 /* Using device tree? */
3730 if (IS_ENABLED(CONFIG_OF) && dev->of_node) {
3731 dev_dbg(dev, "using device tree for GPIO lookup\n");
3732 desc = of_find_gpio(dev, con_id, idx, &lookupflags);
3733 } else if (ACPI_COMPANION(dev)) {
3734 dev_dbg(dev, "using ACPI for GPIO lookup\n");
3735 desc = acpi_find_gpio(dev, con_id, idx, &flags, &lookupflags);
3736 }
3737 }
3738
3739 /*
3740 * Either we are not using DT or ACPI, or their lookup did not return
3741 * a result. In that case, use platform lookup as a fallback.
3742 */
3743 if (!desc || desc == ERR_PTR(-ENOENT)) {
3744 dev_dbg(dev, "using lookup tables for GPIO lookup\n");
3745 desc = gpiod_find(dev, con_id, idx, &lookupflags);
3746 }
3747
3748 if (IS_ERR(desc)) {
3749 dev_dbg(dev, "No GPIO consumer %s found\n", con_id);
3750 return desc;
3751 }
3752
3753 /*
3754 * If a connection label was passed use that, else attempt to use
3755 * the device name as label
3756 */
3757 status = gpiod_request(desc, con_id ? con_id : devname);
3758 if (status < 0)
3759 return ERR_PTR(status);
3760
3761 status = gpiod_configure_flags(desc, con_id, lookupflags, flags);
3762 if (status < 0) {
3763 dev_dbg(dev, "setup of GPIO %s failed\n", con_id);
3764 gpiod_put(desc);
3765 return ERR_PTR(status);
3766 }
3767
3768 return desc;
3769}
3770EXPORT_SYMBOL_GPL(gpiod_get_index);
3771
3772/**
3773 * gpiod_get_from_of_node() - obtain a GPIO from an OF node
3774 * @node: handle of the OF node
3775 * @propname: name of the DT property representing the GPIO
3776 * @index: index of the GPIO to obtain for the consumer
3777 * @dflags: GPIO initialization flags
3778 * @label: label to attach to the requested GPIO
3779 *
3780 * Returns:
3781 * On successful request the GPIO pin is configured in accordance with
3782 * provided @dflags. If the node does not have the requested GPIO
3783 * property, NULL is returned.
3784 *
3785 * In case of error an ERR_PTR() is returned.
3786 */
3787struct gpio_desc *gpiod_get_from_of_node(struct device_node *node,
3788 const char *propname, int index,
3789 enum gpiod_flags dflags,
3790 const char *label)
3791{
3792 struct gpio_desc *desc;
3793 unsigned long lflags = 0;
3794 enum of_gpio_flags flags;
3795 bool active_low = false;
3796 bool single_ended = false;
3797 bool open_drain = false;
3798 bool transitory = false;
3799 int ret;
3800
3801 desc = of_get_named_gpiod_flags(node, propname,
3802 index, &flags);
3803
3804 if (!desc || IS_ERR(desc)) {
3805 /* If it is not there, just return NULL */
3806 if (PTR_ERR(desc) == -ENOENT)
3807 return NULL;
3808 return desc;
3809 }
3810
3811 active_low = flags & OF_GPIO_ACTIVE_LOW;
3812 single_ended = flags & OF_GPIO_SINGLE_ENDED;
3813 open_drain = flags & OF_GPIO_OPEN_DRAIN;
3814 transitory = flags & OF_GPIO_TRANSITORY;
3815
3816 ret = gpiod_request(desc, label);
3817 if (ret)
3818 return ERR_PTR(ret);
3819
3820 if (active_low)
3821 lflags |= GPIO_ACTIVE_LOW;
3822
3823 if (single_ended) {
3824 if (open_drain)
3825 lflags |= GPIO_OPEN_DRAIN;
3826 else
3827 lflags |= GPIO_OPEN_SOURCE;
3828 }
3829
3830 if (transitory)
3831 lflags |= GPIO_TRANSITORY;
3832
3833 ret = gpiod_configure_flags(desc, propname, lflags, dflags);
3834 if (ret < 0) {
3835 gpiod_put(desc);
3836 return ERR_PTR(ret);
3837 }
3838
3839 return desc;
3840}
3841EXPORT_SYMBOL(gpiod_get_from_of_node);
3842
3843/**
3844 * fwnode_get_named_gpiod - obtain a GPIO from firmware node
3845 * @fwnode: handle of the firmware node
3846 * @propname: name of the firmware property representing the GPIO
3847 * @index: index of the GPIO to obtain for the consumer
3848 * @dflags: GPIO initialization flags
3849 * @label: label to attach to the requested GPIO
3850 *
3851 * This function can be used for drivers that get their configuration
3852 * from opaque firmware.
3853 *
3854 * The function properly finds the corresponding GPIO using whatever is the
3855 * underlying firmware interface and then makes sure that the GPIO
3856 * descriptor is requested before it is returned to the caller.
3857 *
3858 * Returns:
3859 * On successful request the GPIO pin is configured in accordance with
3860 * provided @dflags.
3861 *
3862 * In case of error an ERR_PTR() is returned.
3863 */
3864struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode,
3865 const char *propname, int index,
3866 enum gpiod_flags dflags,
3867 const char *label)
3868{
3869 struct gpio_desc *desc = ERR_PTR(-ENODEV);
3870 unsigned long lflags = 0;
3871 int ret;
3872
3873 if (!fwnode)
3874 return ERR_PTR(-EINVAL);
3875
3876 if (is_of_node(fwnode)) {
3877 desc = gpiod_get_from_of_node(to_of_node(fwnode),
3878 propname, index,
3879 dflags,
3880 label);
3881 return desc;
3882 } else if (is_acpi_node(fwnode)) {
3883 struct acpi_gpio_info info;
3884
3885 desc = acpi_node_get_gpiod(fwnode, propname, index, &info);
3886 if (IS_ERR(desc))
3887 return desc;
3888
3889 acpi_gpio_update_gpiod_flags(&dflags, &info);
3890
3891 if (info.polarity == GPIO_ACTIVE_LOW)
3892 lflags |= GPIO_ACTIVE_LOW;
3893 }
3894
3895 /* Currently only ACPI takes this path */
3896 ret = gpiod_request(desc, label);
3897 if (ret)
3898 return ERR_PTR(ret);
3899
3900 ret = gpiod_configure_flags(desc, propname, lflags, dflags);
3901 if (ret < 0) {
3902 gpiod_put(desc);
3903 return ERR_PTR(ret);
3904 }
3905
3906 return desc;
3907}
3908EXPORT_SYMBOL_GPL(fwnode_get_named_gpiod);
3909
3910/**
3911 * gpiod_get_index_optional - obtain an optional GPIO from a multi-index GPIO
3912 * function
3913 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3914 * @con_id: function within the GPIO consumer
3915 * @index: index of the GPIO to obtain in the consumer
3916 * @flags: optional GPIO initialization flags
3917 *
3918 * This is equivalent to gpiod_get_index(), except that when no GPIO with the
3919 * specified index was assigned to the requested function it will return NULL.
3920 * This is convenient for drivers that need to handle optional GPIOs.
3921 */
3922struct gpio_desc *__must_check gpiod_get_index_optional(struct device *dev,
3923 const char *con_id,
3924 unsigned int index,
3925 enum gpiod_flags flags)
3926{
3927 struct gpio_desc *desc;
3928
3929 desc = gpiod_get_index(dev, con_id, index, flags);
3930 if (IS_ERR(desc)) {
3931 if (PTR_ERR(desc) == -ENOENT)
3932 return NULL;
3933 }
3934
3935 return desc;
3936}
3937EXPORT_SYMBOL_GPL(gpiod_get_index_optional);
3938
3939/**
3940 * gpiod_hog - Hog the specified GPIO desc given the provided flags
3941 * @desc: gpio whose value will be assigned
3942 * @name: gpio line name
3943 * @lflags: gpio_lookup_flags - returned from of_find_gpio() or
3944 * of_get_gpio_hog()
3945 * @dflags: gpiod_flags - optional GPIO initialization flags
3946 */
3947int gpiod_hog(struct gpio_desc *desc, const char *name,
3948 unsigned long lflags, enum gpiod_flags dflags)
3949{
3950 struct gpio_chip *chip;
3951 struct gpio_desc *local_desc;
3952 int hwnum;
3953 int status;
3954
3955 chip = gpiod_to_chip(desc);
3956 hwnum = gpio_chip_hwgpio(desc);
3957
3958 local_desc = gpiochip_request_own_desc(chip, hwnum, name);
3959 if (IS_ERR(local_desc)) {
3960 status = PTR_ERR(local_desc);
3961 pr_err("requesting hog GPIO %s (chip %s, offset %d) failed, %d\n",
3962 name, chip->label, hwnum, status);
3963 return status;
3964 }
3965
3966 status = gpiod_configure_flags(desc, name, lflags, dflags);
3967 if (status < 0) {
3968 pr_err("setup of hog GPIO %s (chip %s, offset %d) failed, %d\n",
3969 name, chip->label, hwnum, status);
3970 gpiochip_free_own_desc(desc);
3971 return status;
3972 }
3973
3974 /* Mark GPIO as hogged so it can be identified and removed later */
3975 set_bit(FLAG_IS_HOGGED, &desc->flags);
3976
3977 pr_info("GPIO line %d (%s) hogged as %s%s\n",
3978 desc_to_gpio(desc), name,
3979 (dflags&GPIOD_FLAGS_BIT_DIR_OUT) ? "output" : "input",
3980 (dflags&GPIOD_FLAGS_BIT_DIR_OUT) ?
3981 (dflags&GPIOD_FLAGS_BIT_DIR_VAL) ? "/high" : "/low":"");
3982
3983 return 0;
3984}
3985
3986/**
3987 * gpiochip_free_hogs - Scan gpio-controller chip and release GPIO hog
3988 * @chip: gpio chip to act on
3989 *
3990 * This is only used by of_gpiochip_remove to free hogged gpios
3991 */
3992static void gpiochip_free_hogs(struct gpio_chip *chip)
3993{
3994 int id;
3995
3996 for (id = 0; id < chip->ngpio; id++) {
3997 if (test_bit(FLAG_IS_HOGGED, &chip->gpiodev->descs[id].flags))
3998 gpiochip_free_own_desc(&chip->gpiodev->descs[id]);
3999 }
4000}
4001
4002/**
4003 * gpiod_get_array - obtain multiple GPIOs from a multi-index GPIO function
4004 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4005 * @con_id: function within the GPIO consumer
4006 * @flags: optional GPIO initialization flags
4007 *
4008 * This function acquires all the GPIOs defined under a given function.
4009 *
4010 * Return a struct gpio_descs containing an array of descriptors, -ENOENT if
4011 * no GPIO has been assigned to the requested function, or another IS_ERR()
4012 * code if an error occurred while trying to acquire the GPIOs.
4013 */
4014struct gpio_descs *__must_check gpiod_get_array(struct device *dev,
4015 const char *con_id,
4016 enum gpiod_flags flags)
4017{
4018 struct gpio_desc *desc;
4019 struct gpio_descs *descs;
4020 int count;
4021
4022 count = gpiod_count(dev, con_id);
4023 if (count < 0)
4024 return ERR_PTR(count);
4025
4026 descs = kzalloc(sizeof(*descs) + sizeof(descs->desc[0]) * count,
4027 GFP_KERNEL);
4028 if (!descs)
4029 return ERR_PTR(-ENOMEM);
4030
4031 for (descs->ndescs = 0; descs->ndescs < count; ) {
4032 desc = gpiod_get_index(dev, con_id, descs->ndescs, flags);
4033 if (IS_ERR(desc)) {
4034 gpiod_put_array(descs);
4035 return ERR_CAST(desc);
4036 }
4037 descs->desc[descs->ndescs] = desc;
4038 descs->ndescs++;
4039 }
4040 return descs;
4041}
4042EXPORT_SYMBOL_GPL(gpiod_get_array);
4043
4044/**
4045 * gpiod_get_array_optional - obtain multiple GPIOs from a multi-index GPIO
4046 * function
4047 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4048 * @con_id: function within the GPIO consumer
4049 * @flags: optional GPIO initialization flags
4050 *
4051 * This is equivalent to gpiod_get_array(), except that when no GPIO was
4052 * assigned to the requested function it will return NULL.
4053 */
4054struct gpio_descs *__must_check gpiod_get_array_optional(struct device *dev,
4055 const char *con_id,
4056 enum gpiod_flags flags)
4057{
4058 struct gpio_descs *descs;
4059
4060 descs = gpiod_get_array(dev, con_id, flags);
4061 if (IS_ERR(descs) && (PTR_ERR(descs) == -ENOENT))
4062 return NULL;
4063
4064 return descs;
4065}
4066EXPORT_SYMBOL_GPL(gpiod_get_array_optional);
4067
4068/**
4069 * gpiod_put - dispose of a GPIO descriptor
4070 * @desc: GPIO descriptor to dispose of
4071 *
4072 * No descriptor can be used after gpiod_put() has been called on it.
4073 */
4074void gpiod_put(struct gpio_desc *desc)
4075{
4076 gpiod_free(desc);
4077}
4078EXPORT_SYMBOL_GPL(gpiod_put);
4079
4080/**
4081 * gpiod_put_array - dispose of multiple GPIO descriptors
4082 * @descs: struct gpio_descs containing an array of descriptors
4083 */
4084void gpiod_put_array(struct gpio_descs *descs)
4085{
4086 unsigned int i;
4087
4088 for (i = 0; i < descs->ndescs; i++)
4089 gpiod_put(descs->desc[i]);
4090
4091 kfree(descs);
4092}
4093EXPORT_SYMBOL_GPL(gpiod_put_array);
4094
4095static int __init gpiolib_dev_init(void)
4096{
4097 int ret;
4098
4099 /* Register GPIO sysfs bus */
4100 ret = bus_register(&gpio_bus_type);
4101 if (ret < 0) {
4102 pr_err("gpiolib: could not register GPIO bus type\n");
4103 return ret;
4104 }
4105
4106 ret = alloc_chrdev_region(&gpio_devt, 0, GPIO_DEV_MAX, "gpiochip");
4107 if (ret < 0) {
4108 pr_err("gpiolib: failed to allocate char dev region\n");
4109 bus_unregister(&gpio_bus_type);
4110 } else {
4111 gpiolib_initialized = true;
4112 gpiochip_setup_devs();
4113 }
4114 return ret;
4115}
4116core_initcall(gpiolib_dev_init);
4117
4118#ifdef CONFIG_DEBUG_FS
4119
4120static void gpiolib_dbg_show(struct seq_file *s, struct gpio_device *gdev)
4121{
4122 unsigned i;
4123 struct gpio_chip *chip = gdev->chip;
4124 unsigned gpio = gdev->base;
4125 struct gpio_desc *gdesc = &gdev->descs[0];
4126 int is_out;
4127 int is_irq;
4128
4129 for (i = 0; i < gdev->ngpio; i++, gpio++, gdesc++) {
4130 if (!test_bit(FLAG_REQUESTED, &gdesc->flags)) {
4131 if (gdesc->name) {
4132 seq_printf(s, " gpio-%-3d (%-20.20s)\n",
4133 gpio, gdesc->name);
4134 }
4135 continue;
4136 }
4137
4138 gpiod_get_direction(gdesc);
4139 is_out = test_bit(FLAG_IS_OUT, &gdesc->flags);
4140 is_irq = test_bit(FLAG_USED_AS_IRQ, &gdesc->flags);
4141 seq_printf(s, " gpio-%-3d (%-20.20s|%-20.20s) %s %s %s",
4142 gpio, gdesc->name ? gdesc->name : "", gdesc->label,
4143 is_out ? "out" : "in ",
4144 chip->get
4145 ? (chip->get(chip, i) ? "hi" : "lo")
4146 : "? ",
4147 is_irq ? "IRQ" : " ");
4148 seq_printf(s, "\n");
4149 }
4150}
4151
4152static void *gpiolib_seq_start(struct seq_file *s, loff_t *pos)
4153{
4154 unsigned long flags;
4155 struct gpio_device *gdev = NULL;
4156 loff_t index = *pos;
4157
4158 s->private = "";
4159
4160 spin_lock_irqsave(&gpio_lock, flags);
4161 list_for_each_entry(gdev, &gpio_devices, list)
4162 if (index-- == 0) {
4163 spin_unlock_irqrestore(&gpio_lock, flags);
4164 return gdev;
4165 }
4166 spin_unlock_irqrestore(&gpio_lock, flags);
4167
4168 return NULL;
4169}
4170
4171static void *gpiolib_seq_next(struct seq_file *s, void *v, loff_t *pos)
4172{
4173 unsigned long flags;
4174 struct gpio_device *gdev = v;
4175 void *ret = NULL;
4176
4177 spin_lock_irqsave(&gpio_lock, flags);
4178 if (list_is_last(&gdev->list, &gpio_devices))
4179 ret = NULL;
4180 else
4181 ret = list_entry(gdev->list.next, struct gpio_device, list);
4182 spin_unlock_irqrestore(&gpio_lock, flags);
4183
4184 s->private = "\n";
4185 ++*pos;
4186
4187 return ret;
4188}
4189
4190static void gpiolib_seq_stop(struct seq_file *s, void *v)
4191{
4192}
4193
4194static int gpiolib_seq_show(struct seq_file *s, void *v)
4195{
4196 struct gpio_device *gdev = v;
4197 struct gpio_chip *chip = gdev->chip;
4198 struct device *parent;
4199
4200 if (!chip) {
4201 seq_printf(s, "%s%s: (dangling chip)", (char *)s->private,
4202 dev_name(&gdev->dev));
4203 return 0;
4204 }
4205
4206 seq_printf(s, "%s%s: GPIOs %d-%d", (char *)s->private,
4207 dev_name(&gdev->dev),
4208 gdev->base, gdev->base + gdev->ngpio - 1);
4209 parent = chip->parent;
4210 if (parent)
4211 seq_printf(s, ", parent: %s/%s",
4212 parent->bus ? parent->bus->name : "no-bus",
4213 dev_name(parent));
4214 if (chip->label)
4215 seq_printf(s, ", %s", chip->label);
4216 if (chip->can_sleep)
4217 seq_printf(s, ", can sleep");
4218 seq_printf(s, ":\n");
4219
4220 if (chip->dbg_show)
4221 chip->dbg_show(s, chip);
4222 else
4223 gpiolib_dbg_show(s, gdev);
4224
4225 return 0;
4226}
4227
4228static const struct seq_operations gpiolib_seq_ops = {
4229 .start = gpiolib_seq_start,
4230 .next = gpiolib_seq_next,
4231 .stop = gpiolib_seq_stop,
4232 .show = gpiolib_seq_show,
4233};
4234
4235static int gpiolib_open(struct inode *inode, struct file *file)
4236{
4237 return seq_open(file, &gpiolib_seq_ops);
4238}
4239
4240static const struct file_operations gpiolib_operations = {
4241 .owner = THIS_MODULE,
4242 .open = gpiolib_open,
4243 .read = seq_read,
4244 .llseek = seq_lseek,
4245 .release = seq_release,
4246};
4247
4248static int __init gpiolib_debugfs_init(void)
4249{
4250 /* /sys/kernel/debug/gpio */
4251 (void) debugfs_create_file("gpio", S_IFREG | S_IRUGO,
4252 NULL, NULL, &gpiolib_operations);
4253 return 0;
4254}
4255subsys_initcall(gpiolib_debugfs_init);
4256
4257#endif /* DEBUG_FS */