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1/*
2 * ACPI helpers for GPIO API
3 *
4 * Copyright (C) 2012, Intel Corporation
5 * Authors: Mathias Nyman <mathias.nyman@linux.intel.com>
6 * Mika Westerberg <mika.westerberg@linux.intel.com>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
11 */
12
13#include <linux/errno.h>
14#include <linux/gpio.h>
15#include <linux/gpio/consumer.h>
16#include <linux/gpio/driver.h>
17#include <linux/gpio/machine.h>
18#include <linux/export.h>
19#include <linux/acpi.h>
20#include <linux/interrupt.h>
21#include <linux/mutex.h>
22#include <linux/pinctrl/pinctrl.h>
23
24#include "gpiolib.h"
25
26struct acpi_gpio_event {
27 struct list_head node;
28 acpi_handle handle;
29 unsigned int pin;
30 unsigned int irq;
31 struct gpio_desc *desc;
32};
33
34struct acpi_gpio_connection {
35 struct list_head node;
36 unsigned int pin;
37 struct gpio_desc *desc;
38};
39
40struct acpi_gpio_chip {
41 /*
42 * ACPICA requires that the first field of the context parameter
43 * passed to acpi_install_address_space_handler() is large enough
44 * to hold struct acpi_connection_info.
45 */
46 struct acpi_connection_info conn_info;
47 struct list_head conns;
48 struct mutex conn_lock;
49 struct gpio_chip *chip;
50 struct list_head events;
51};
52
53static int acpi_gpiochip_find(struct gpio_chip *gc, void *data)
54{
55 if (!gc->parent)
56 return false;
57
58 return ACPI_HANDLE(gc->parent) == data;
59}
60
61#ifdef CONFIG_PINCTRL
62/**
63 * acpi_gpiochip_pin_to_gpio_offset() - translates ACPI GPIO to Linux GPIO
64 * @chip: GPIO chip
65 * @pin: ACPI GPIO pin number from GpioIo/GpioInt resource
66 *
67 * Function takes ACPI GpioIo/GpioInt pin number as a parameter and
68 * translates it to a corresponding offset suitable to be passed to a
69 * GPIO controller driver.
70 *
71 * Typically the returned offset is same as @pin, but if the GPIO
72 * controller uses pin controller and the mapping is not contiguous the
73 * offset might be different.
74 */
75static int acpi_gpiochip_pin_to_gpio_offset(struct gpio_device *gdev, int pin)
76{
77 struct gpio_pin_range *pin_range;
78
79 /* If there are no ranges in this chip, use 1:1 mapping */
80 if (list_empty(&gdev->pin_ranges))
81 return pin;
82
83 list_for_each_entry(pin_range, &gdev->pin_ranges, node) {
84 const struct pinctrl_gpio_range *range = &pin_range->range;
85 int i;
86
87 if (range->pins) {
88 for (i = 0; i < range->npins; i++) {
89 if (range->pins[i] == pin)
90 return range->base + i - gdev->base;
91 }
92 } else {
93 if (pin >= range->pin_base &&
94 pin < range->pin_base + range->npins) {
95 unsigned gpio_base;
96
97 gpio_base = range->base - gdev->base;
98 return gpio_base + pin - range->pin_base;
99 }
100 }
101 }
102
103 return -EINVAL;
104}
105#else
106static inline int acpi_gpiochip_pin_to_gpio_offset(struct gpio_device *gdev,
107 int pin)
108{
109 return pin;
110}
111#endif
112
113/**
114 * acpi_get_gpiod() - Translate ACPI GPIO pin to GPIO descriptor usable with GPIO API
115 * @path: ACPI GPIO controller full path name, (e.g. "\\_SB.GPO1")
116 * @pin: ACPI GPIO pin number (0-based, controller-relative)
117 *
118 * Return: GPIO descriptor to use with Linux generic GPIO API, or ERR_PTR
119 * error value. Specifically returns %-EPROBE_DEFER if the referenced GPIO
120 * controller does not have gpiochip registered at the moment. This is to
121 * support probe deferral.
122 */
123static struct gpio_desc *acpi_get_gpiod(char *path, int pin)
124{
125 struct gpio_chip *chip;
126 acpi_handle handle;
127 acpi_status status;
128 int offset;
129
130 status = acpi_get_handle(NULL, path, &handle);
131 if (ACPI_FAILURE(status))
132 return ERR_PTR(-ENODEV);
133
134 chip = gpiochip_find(handle, acpi_gpiochip_find);
135 if (!chip)
136 return ERR_PTR(-EPROBE_DEFER);
137
138 offset = acpi_gpiochip_pin_to_gpio_offset(chip->gpiodev, pin);
139 if (offset < 0)
140 return ERR_PTR(offset);
141
142 return gpiochip_get_desc(chip, offset);
143}
144
145static irqreturn_t acpi_gpio_irq_handler(int irq, void *data)
146{
147 struct acpi_gpio_event *event = data;
148
149 acpi_evaluate_object(event->handle, NULL, NULL, NULL);
150
151 return IRQ_HANDLED;
152}
153
154static irqreturn_t acpi_gpio_irq_handler_evt(int irq, void *data)
155{
156 struct acpi_gpio_event *event = data;
157
158 acpi_execute_simple_method(event->handle, NULL, event->pin);
159
160 return IRQ_HANDLED;
161}
162
163static void acpi_gpio_chip_dh(acpi_handle handle, void *data)
164{
165 /* The address of this function is used as a key. */
166}
167
168static acpi_status acpi_gpiochip_request_interrupt(struct acpi_resource *ares,
169 void *context)
170{
171 struct acpi_gpio_chip *acpi_gpio = context;
172 struct gpio_chip *chip = acpi_gpio->chip;
173 struct acpi_resource_gpio *agpio;
174 acpi_handle handle, evt_handle;
175 struct acpi_gpio_event *event;
176 irq_handler_t handler = NULL;
177 struct gpio_desc *desc;
178 unsigned long irqflags;
179 int ret, pin, irq;
180
181 if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
182 return AE_OK;
183
184 agpio = &ares->data.gpio;
185 if (agpio->connection_type != ACPI_RESOURCE_GPIO_TYPE_INT)
186 return AE_OK;
187
188 handle = ACPI_HANDLE(chip->parent);
189 pin = agpio->pin_table[0];
190
191 if (pin <= 255) {
192 char ev_name[5];
193 sprintf(ev_name, "_%c%02X",
194 agpio->triggering == ACPI_EDGE_SENSITIVE ? 'E' : 'L',
195 pin);
196 if (ACPI_SUCCESS(acpi_get_handle(handle, ev_name, &evt_handle)))
197 handler = acpi_gpio_irq_handler;
198 }
199 if (!handler) {
200 if (ACPI_SUCCESS(acpi_get_handle(handle, "_EVT", &evt_handle)))
201 handler = acpi_gpio_irq_handler_evt;
202 }
203 if (!handler)
204 return AE_BAD_PARAMETER;
205
206 pin = acpi_gpiochip_pin_to_gpio_offset(chip->gpiodev, pin);
207 if (pin < 0)
208 return AE_BAD_PARAMETER;
209
210 desc = gpiochip_request_own_desc(chip, pin, "ACPI:Event");
211 if (IS_ERR(desc)) {
212 dev_err(chip->parent, "Failed to request GPIO\n");
213 return AE_ERROR;
214 }
215
216 gpiod_direction_input(desc);
217
218 ret = gpiochip_lock_as_irq(chip, pin);
219 if (ret) {
220 dev_err(chip->parent, "Failed to lock GPIO as interrupt\n");
221 goto fail_free_desc;
222 }
223
224 irq = gpiod_to_irq(desc);
225 if (irq < 0) {
226 dev_err(chip->parent, "Failed to translate GPIO to IRQ\n");
227 goto fail_unlock_irq;
228 }
229
230 irqflags = IRQF_ONESHOT;
231 if (agpio->triggering == ACPI_LEVEL_SENSITIVE) {
232 if (agpio->polarity == ACPI_ACTIVE_HIGH)
233 irqflags |= IRQF_TRIGGER_HIGH;
234 else
235 irqflags |= IRQF_TRIGGER_LOW;
236 } else {
237 switch (agpio->polarity) {
238 case ACPI_ACTIVE_HIGH:
239 irqflags |= IRQF_TRIGGER_RISING;
240 break;
241 case ACPI_ACTIVE_LOW:
242 irqflags |= IRQF_TRIGGER_FALLING;
243 break;
244 default:
245 irqflags |= IRQF_TRIGGER_RISING |
246 IRQF_TRIGGER_FALLING;
247 break;
248 }
249 }
250
251 event = kzalloc(sizeof(*event), GFP_KERNEL);
252 if (!event)
253 goto fail_unlock_irq;
254
255 event->handle = evt_handle;
256 event->irq = irq;
257 event->pin = pin;
258 event->desc = desc;
259
260 ret = request_threaded_irq(event->irq, NULL, handler, irqflags,
261 "ACPI:Event", event);
262 if (ret) {
263 dev_err(chip->parent,
264 "Failed to setup interrupt handler for %d\n",
265 event->irq);
266 goto fail_free_event;
267 }
268
269 list_add_tail(&event->node, &acpi_gpio->events);
270 return AE_OK;
271
272fail_free_event:
273 kfree(event);
274fail_unlock_irq:
275 gpiochip_unlock_as_irq(chip, pin);
276fail_free_desc:
277 gpiochip_free_own_desc(desc);
278
279 return AE_ERROR;
280}
281
282/**
283 * acpi_gpiochip_request_interrupts() - Register isr for gpio chip ACPI events
284 * @chip: GPIO chip
285 *
286 * ACPI5 platforms can use GPIO signaled ACPI events. These GPIO interrupts are
287 * handled by ACPI event methods which need to be called from the GPIO
288 * chip's interrupt handler. acpi_gpiochip_request_interrupts finds out which
289 * gpio pins have acpi event methods and assigns interrupt handlers that calls
290 * the acpi event methods for those pins.
291 */
292void acpi_gpiochip_request_interrupts(struct gpio_chip *chip)
293{
294 struct acpi_gpio_chip *acpi_gpio;
295 acpi_handle handle;
296 acpi_status status;
297
298 if (!chip->parent || !chip->to_irq)
299 return;
300
301 handle = ACPI_HANDLE(chip->parent);
302 if (!handle)
303 return;
304
305 status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
306 if (ACPI_FAILURE(status))
307 return;
308
309 acpi_walk_resources(handle, "_AEI",
310 acpi_gpiochip_request_interrupt, acpi_gpio);
311}
312EXPORT_SYMBOL_GPL(acpi_gpiochip_request_interrupts);
313
314/**
315 * acpi_gpiochip_free_interrupts() - Free GPIO ACPI event interrupts.
316 * @chip: GPIO chip
317 *
318 * Free interrupts associated with GPIO ACPI event method for the given
319 * GPIO chip.
320 */
321void acpi_gpiochip_free_interrupts(struct gpio_chip *chip)
322{
323 struct acpi_gpio_chip *acpi_gpio;
324 struct acpi_gpio_event *event, *ep;
325 acpi_handle handle;
326 acpi_status status;
327
328 if (!chip->parent || !chip->to_irq)
329 return;
330
331 handle = ACPI_HANDLE(chip->parent);
332 if (!handle)
333 return;
334
335 status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
336 if (ACPI_FAILURE(status))
337 return;
338
339 list_for_each_entry_safe_reverse(event, ep, &acpi_gpio->events, node) {
340 struct gpio_desc *desc;
341
342 free_irq(event->irq, event);
343 desc = event->desc;
344 if (WARN_ON(IS_ERR(desc)))
345 continue;
346 gpiochip_unlock_as_irq(chip, event->pin);
347 gpiochip_free_own_desc(desc);
348 list_del(&event->node);
349 kfree(event);
350 }
351}
352EXPORT_SYMBOL_GPL(acpi_gpiochip_free_interrupts);
353
354int acpi_dev_add_driver_gpios(struct acpi_device *adev,
355 const struct acpi_gpio_mapping *gpios)
356{
357 if (adev && gpios) {
358 adev->driver_gpios = gpios;
359 return 0;
360 }
361 return -EINVAL;
362}
363EXPORT_SYMBOL_GPL(acpi_dev_add_driver_gpios);
364
365static bool acpi_get_driver_gpio_data(struct acpi_device *adev,
366 const char *name, int index,
367 struct acpi_reference_args *args)
368{
369 const struct acpi_gpio_mapping *gm;
370
371 if (!adev->driver_gpios)
372 return false;
373
374 for (gm = adev->driver_gpios; gm->name; gm++)
375 if (!strcmp(name, gm->name) && gm->data && index < gm->size) {
376 const struct acpi_gpio_params *par = gm->data + index;
377
378 args->adev = adev;
379 args->args[0] = par->crs_entry_index;
380 args->args[1] = par->line_index;
381 args->args[2] = par->active_low;
382 args->nargs = 3;
383 return true;
384 }
385
386 return false;
387}
388
389struct acpi_gpio_lookup {
390 struct acpi_gpio_info info;
391 int index;
392 int pin_index;
393 bool active_low;
394 struct acpi_device *adev;
395 struct gpio_desc *desc;
396 int n;
397};
398
399static int acpi_populate_gpio_lookup(struct acpi_resource *ares, void *data)
400{
401 struct acpi_gpio_lookup *lookup = data;
402
403 if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
404 return 1;
405
406 if (lookup->n++ == lookup->index && !lookup->desc) {
407 const struct acpi_resource_gpio *agpio = &ares->data.gpio;
408 int pin_index = lookup->pin_index;
409
410 if (pin_index >= agpio->pin_table_length)
411 return 1;
412
413 lookup->desc = acpi_get_gpiod(agpio->resource_source.string_ptr,
414 agpio->pin_table[pin_index]);
415 lookup->info.gpioint =
416 agpio->connection_type == ACPI_RESOURCE_GPIO_TYPE_INT;
417
418 /*
419 * ActiveLow is only specified for GpioInt resource. If
420 * GpioIo is used then the only way to set the flag is
421 * to use _DSD "gpios" property.
422 * Note: we expect here:
423 * - ACPI_ACTIVE_LOW == GPIO_ACTIVE_LOW
424 * - ACPI_ACTIVE_HIGH == GPIO_ACTIVE_HIGH
425 */
426 if (lookup->info.gpioint) {
427 lookup->info.polarity = agpio->polarity;
428 lookup->info.triggering = agpio->triggering;
429 }
430
431 }
432
433 return 1;
434}
435
436static int acpi_gpio_resource_lookup(struct acpi_gpio_lookup *lookup,
437 struct acpi_gpio_info *info)
438{
439 struct list_head res_list;
440 int ret;
441
442 INIT_LIST_HEAD(&res_list);
443
444 ret = acpi_dev_get_resources(lookup->adev, &res_list,
445 acpi_populate_gpio_lookup,
446 lookup);
447 if (ret < 0)
448 return ret;
449
450 acpi_dev_free_resource_list(&res_list);
451
452 if (!lookup->desc)
453 return -ENOENT;
454
455 if (info) {
456 *info = lookup->info;
457 if (lookup->active_low)
458 info->polarity = lookup->active_low;
459 }
460 return 0;
461}
462
463static int acpi_gpio_property_lookup(struct fwnode_handle *fwnode,
464 const char *propname, int index,
465 struct acpi_gpio_lookup *lookup)
466{
467 struct acpi_reference_args args;
468 int ret;
469
470 memset(&args, 0, sizeof(args));
471 ret = __acpi_node_get_property_reference(fwnode, propname, index, 3,
472 &args);
473 if (ret) {
474 struct acpi_device *adev = to_acpi_device_node(fwnode);
475
476 if (!adev)
477 return ret;
478
479 if (!acpi_get_driver_gpio_data(adev, propname, index, &args))
480 return ret;
481 }
482 /*
483 * The property was found and resolved, so need to lookup the GPIO based
484 * on returned args.
485 */
486 lookup->adev = args.adev;
487 if (args.nargs != 3)
488 return -EPROTO;
489
490 lookup->index = args.args[0];
491 lookup->pin_index = args.args[1];
492 lookup->active_low = !!args.args[2];
493
494 return 0;
495}
496
497/**
498 * acpi_get_gpiod_by_index() - get a GPIO descriptor from device resources
499 * @adev: pointer to a ACPI device to get GPIO from
500 * @propname: Property name of the GPIO (optional)
501 * @index: index of GpioIo/GpioInt resource (starting from %0)
502 * @info: info pointer to fill in (optional)
503 *
504 * Function goes through ACPI resources for @adev and based on @index looks
505 * up a GpioIo/GpioInt resource, translates it to the Linux GPIO descriptor,
506 * and returns it. @index matches GpioIo/GpioInt resources only so if there
507 * are total %3 GPIO resources, the index goes from %0 to %2.
508 *
509 * If @propname is specified the GPIO is looked using device property. In
510 * that case @index is used to select the GPIO entry in the property value
511 * (in case of multiple).
512 *
513 * If the GPIO cannot be translated or there is an error an ERR_PTR is
514 * returned.
515 *
516 * Note: if the GPIO resource has multiple entries in the pin list, this
517 * function only returns the first.
518 */
519static struct gpio_desc *acpi_get_gpiod_by_index(struct acpi_device *adev,
520 const char *propname, int index,
521 struct acpi_gpio_info *info)
522{
523 struct acpi_gpio_lookup lookup;
524 int ret;
525
526 if (!adev)
527 return ERR_PTR(-ENODEV);
528
529 memset(&lookup, 0, sizeof(lookup));
530 lookup.index = index;
531
532 if (propname) {
533 dev_dbg(&adev->dev, "GPIO: looking up %s\n", propname);
534
535 ret = acpi_gpio_property_lookup(acpi_fwnode_handle(adev),
536 propname, index, &lookup);
537 if (ret)
538 return ERR_PTR(ret);
539
540 dev_dbg(&adev->dev, "GPIO: _DSD returned %s %d %d %u\n",
541 dev_name(&lookup.adev->dev), lookup.index,
542 lookup.pin_index, lookup.active_low);
543 } else {
544 dev_dbg(&adev->dev, "GPIO: looking up %d in _CRS\n", index);
545 lookup.adev = adev;
546 }
547
548 ret = acpi_gpio_resource_lookup(&lookup, info);
549 return ret ? ERR_PTR(ret) : lookup.desc;
550}
551
552struct gpio_desc *acpi_find_gpio(struct device *dev,
553 const char *con_id,
554 unsigned int idx,
555 enum gpiod_flags flags,
556 enum gpio_lookup_flags *lookupflags)
557{
558 struct acpi_device *adev = ACPI_COMPANION(dev);
559 struct acpi_gpio_info info;
560 struct gpio_desc *desc;
561 char propname[32];
562 int i;
563
564 /* Try first from _DSD */
565 for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
566 if (con_id && strcmp(con_id, "gpios")) {
567 snprintf(propname, sizeof(propname), "%s-%s",
568 con_id, gpio_suffixes[i]);
569 } else {
570 snprintf(propname, sizeof(propname), "%s",
571 gpio_suffixes[i]);
572 }
573
574 desc = acpi_get_gpiod_by_index(adev, propname, idx, &info);
575 if (!IS_ERR(desc))
576 break;
577 if (PTR_ERR(desc) == -EPROBE_DEFER)
578 return ERR_CAST(desc);
579 }
580
581 /* Then from plain _CRS GPIOs */
582 if (IS_ERR(desc)) {
583 if (!acpi_can_fallback_to_crs(adev, con_id))
584 return ERR_PTR(-ENOENT);
585
586 desc = acpi_get_gpiod_by_index(adev, NULL, idx, &info);
587 if (IS_ERR(desc))
588 return desc;
589
590 if ((flags == GPIOD_OUT_LOW || flags == GPIOD_OUT_HIGH) &&
591 info.gpioint) {
592 dev_dbg(dev, "refusing GpioInt() entry when doing GPIOD_OUT_* lookup\n");
593 return ERR_PTR(-ENOENT);
594 }
595 }
596
597 if (info.polarity == GPIO_ACTIVE_LOW)
598 *lookupflags |= GPIO_ACTIVE_LOW;
599
600 return desc;
601}
602
603/**
604 * acpi_node_get_gpiod() - get a GPIO descriptor from ACPI resources
605 * @fwnode: pointer to an ACPI firmware node to get the GPIO information from
606 * @propname: Property name of the GPIO
607 * @index: index of GpioIo/GpioInt resource (starting from %0)
608 * @info: info pointer to fill in (optional)
609 *
610 * If @fwnode is an ACPI device object, call %acpi_get_gpiod_by_index() for it.
611 * Otherwise (ie. it is a data-only non-device object), use the property-based
612 * GPIO lookup to get to the GPIO resource with the relevant information and use
613 * that to obtain the GPIO descriptor to return.
614 */
615struct gpio_desc *acpi_node_get_gpiod(struct fwnode_handle *fwnode,
616 const char *propname, int index,
617 struct acpi_gpio_info *info)
618{
619 struct acpi_gpio_lookup lookup;
620 struct acpi_device *adev;
621 int ret;
622
623 adev = to_acpi_device_node(fwnode);
624 if (adev)
625 return acpi_get_gpiod_by_index(adev, propname, index, info);
626
627 if (!is_acpi_data_node(fwnode))
628 return ERR_PTR(-ENODEV);
629
630 if (!propname)
631 return ERR_PTR(-EINVAL);
632
633 memset(&lookup, 0, sizeof(lookup));
634 lookup.index = index;
635
636 ret = acpi_gpio_property_lookup(fwnode, propname, index, &lookup);
637 if (ret)
638 return ERR_PTR(ret);
639
640 ret = acpi_gpio_resource_lookup(&lookup, info);
641 return ret ? ERR_PTR(ret) : lookup.desc;
642}
643
644/**
645 * acpi_dev_gpio_irq_get() - Find GpioInt and translate it to Linux IRQ number
646 * @adev: pointer to a ACPI device to get IRQ from
647 * @index: index of GpioInt resource (starting from %0)
648 *
649 * If the device has one or more GpioInt resources, this function can be
650 * used to translate from the GPIO offset in the resource to the Linux IRQ
651 * number.
652 *
653 * Return: Linux IRQ number (>%0) on success, negative errno on failure.
654 */
655int acpi_dev_gpio_irq_get(struct acpi_device *adev, int index)
656{
657 int idx, i;
658 unsigned int irq_flags;
659 int ret = -ENOENT;
660
661 for (i = 0, idx = 0; idx <= index; i++) {
662 struct acpi_gpio_info info;
663 struct gpio_desc *desc;
664
665 desc = acpi_get_gpiod_by_index(adev, NULL, i, &info);
666 if (IS_ERR(desc)) {
667 ret = PTR_ERR(desc);
668 break;
669 }
670 if (info.gpioint && idx++ == index) {
671 int irq = gpiod_to_irq(desc);
672
673 if (irq < 0)
674 return irq;
675
676 irq_flags = acpi_dev_get_irq_type(info.triggering,
677 info.polarity);
678
679 /* Set type if specified and different than the current one */
680 if (irq_flags != IRQ_TYPE_NONE &&
681 irq_flags != irq_get_trigger_type(irq))
682 irq_set_irq_type(irq, irq_flags);
683
684 return irq;
685 }
686
687 }
688 return ret;
689}
690EXPORT_SYMBOL_GPL(acpi_dev_gpio_irq_get);
691
692static acpi_status
693acpi_gpio_adr_space_handler(u32 function, acpi_physical_address address,
694 u32 bits, u64 *value, void *handler_context,
695 void *region_context)
696{
697 struct acpi_gpio_chip *achip = region_context;
698 struct gpio_chip *chip = achip->chip;
699 struct acpi_resource_gpio *agpio;
700 struct acpi_resource *ares;
701 int pin_index = (int)address;
702 acpi_status status;
703 bool pull_up;
704 int length;
705 int i;
706
707 status = acpi_buffer_to_resource(achip->conn_info.connection,
708 achip->conn_info.length, &ares);
709 if (ACPI_FAILURE(status))
710 return status;
711
712 if (WARN_ON(ares->type != ACPI_RESOURCE_TYPE_GPIO)) {
713 ACPI_FREE(ares);
714 return AE_BAD_PARAMETER;
715 }
716
717 agpio = &ares->data.gpio;
718 pull_up = agpio->pin_config == ACPI_PIN_CONFIG_PULLUP;
719
720 if (WARN_ON(agpio->io_restriction == ACPI_IO_RESTRICT_INPUT &&
721 function == ACPI_WRITE)) {
722 ACPI_FREE(ares);
723 return AE_BAD_PARAMETER;
724 }
725
726 length = min(agpio->pin_table_length, (u16)(pin_index + bits));
727 for (i = pin_index; i < length; ++i) {
728 int pin = agpio->pin_table[i];
729 struct acpi_gpio_connection *conn;
730 struct gpio_desc *desc;
731 bool found;
732
733 pin = acpi_gpiochip_pin_to_gpio_offset(chip->gpiodev, pin);
734 if (pin < 0) {
735 status = AE_BAD_PARAMETER;
736 goto out;
737 }
738
739 mutex_lock(&achip->conn_lock);
740
741 found = false;
742 list_for_each_entry(conn, &achip->conns, node) {
743 if (conn->pin == pin) {
744 found = true;
745 desc = conn->desc;
746 break;
747 }
748 }
749
750 /*
751 * The same GPIO can be shared between operation region and
752 * event but only if the access here is ACPI_READ. In that
753 * case we "borrow" the event GPIO instead.
754 */
755 if (!found && agpio->sharable == ACPI_SHARED &&
756 function == ACPI_READ) {
757 struct acpi_gpio_event *event;
758
759 list_for_each_entry(event, &achip->events, node) {
760 if (event->pin == pin) {
761 desc = event->desc;
762 found = true;
763 break;
764 }
765 }
766 }
767
768 if (!found) {
769 desc = gpiochip_request_own_desc(chip, pin,
770 "ACPI:OpRegion");
771 if (IS_ERR(desc)) {
772 status = AE_ERROR;
773 mutex_unlock(&achip->conn_lock);
774 goto out;
775 }
776
777 switch (agpio->io_restriction) {
778 case ACPI_IO_RESTRICT_INPUT:
779 gpiod_direction_input(desc);
780 break;
781 case ACPI_IO_RESTRICT_OUTPUT:
782 /*
783 * ACPI GPIO resources don't contain an
784 * initial value for the GPIO. Therefore we
785 * deduce that value from the pull field
786 * instead. If the pin is pulled up we
787 * assume default to be high, otherwise
788 * low.
789 */
790 gpiod_direction_output(desc, pull_up);
791 break;
792 default:
793 /*
794 * Assume that the BIOS has configured the
795 * direction and pull accordingly.
796 */
797 break;
798 }
799
800 conn = kzalloc(sizeof(*conn), GFP_KERNEL);
801 if (!conn) {
802 status = AE_NO_MEMORY;
803 gpiochip_free_own_desc(desc);
804 mutex_unlock(&achip->conn_lock);
805 goto out;
806 }
807
808 conn->pin = pin;
809 conn->desc = desc;
810 list_add_tail(&conn->node, &achip->conns);
811 }
812
813 mutex_unlock(&achip->conn_lock);
814
815 if (function == ACPI_WRITE)
816 gpiod_set_raw_value_cansleep(desc,
817 !!((1 << i) & *value));
818 else
819 *value |= (u64)gpiod_get_raw_value_cansleep(desc) << i;
820 }
821
822out:
823 ACPI_FREE(ares);
824 return status;
825}
826
827static void acpi_gpiochip_request_regions(struct acpi_gpio_chip *achip)
828{
829 struct gpio_chip *chip = achip->chip;
830 acpi_handle handle = ACPI_HANDLE(chip->parent);
831 acpi_status status;
832
833 INIT_LIST_HEAD(&achip->conns);
834 mutex_init(&achip->conn_lock);
835 status = acpi_install_address_space_handler(handle, ACPI_ADR_SPACE_GPIO,
836 acpi_gpio_adr_space_handler,
837 NULL, achip);
838 if (ACPI_FAILURE(status))
839 dev_err(chip->parent,
840 "Failed to install GPIO OpRegion handler\n");
841}
842
843static void acpi_gpiochip_free_regions(struct acpi_gpio_chip *achip)
844{
845 struct gpio_chip *chip = achip->chip;
846 acpi_handle handle = ACPI_HANDLE(chip->parent);
847 struct acpi_gpio_connection *conn, *tmp;
848 acpi_status status;
849
850 status = acpi_remove_address_space_handler(handle, ACPI_ADR_SPACE_GPIO,
851 acpi_gpio_adr_space_handler);
852 if (ACPI_FAILURE(status)) {
853 dev_err(chip->parent,
854 "Failed to remove GPIO OpRegion handler\n");
855 return;
856 }
857
858 list_for_each_entry_safe_reverse(conn, tmp, &achip->conns, node) {
859 gpiochip_free_own_desc(conn->desc);
860 list_del(&conn->node);
861 kfree(conn);
862 }
863}
864
865static struct gpio_desc *acpi_gpiochip_parse_own_gpio(
866 struct acpi_gpio_chip *achip, struct fwnode_handle *fwnode,
867 const char **name, unsigned int *lflags, unsigned int *dflags)
868{
869 struct gpio_chip *chip = achip->chip;
870 struct gpio_desc *desc;
871 u32 gpios[2];
872 int ret;
873
874 *lflags = 0;
875 *dflags = 0;
876 *name = NULL;
877
878 ret = fwnode_property_read_u32_array(fwnode, "gpios", gpios,
879 ARRAY_SIZE(gpios));
880 if (ret < 0)
881 return ERR_PTR(ret);
882
883 ret = acpi_gpiochip_pin_to_gpio_offset(chip->gpiodev, gpios[0]);
884 if (ret < 0)
885 return ERR_PTR(ret);
886
887 desc = gpiochip_get_desc(chip, ret);
888 if (IS_ERR(desc))
889 return desc;
890
891 if (gpios[1])
892 *lflags |= GPIO_ACTIVE_LOW;
893
894 if (fwnode_property_present(fwnode, "input"))
895 *dflags |= GPIOD_IN;
896 else if (fwnode_property_present(fwnode, "output-low"))
897 *dflags |= GPIOD_OUT_LOW;
898 else if (fwnode_property_present(fwnode, "output-high"))
899 *dflags |= GPIOD_OUT_HIGH;
900 else
901 return ERR_PTR(-EINVAL);
902
903 fwnode_property_read_string(fwnode, "line-name", name);
904
905 return desc;
906}
907
908static void acpi_gpiochip_scan_gpios(struct acpi_gpio_chip *achip)
909{
910 struct gpio_chip *chip = achip->chip;
911 struct fwnode_handle *fwnode;
912
913 device_for_each_child_node(chip->parent, fwnode) {
914 unsigned int lflags, dflags;
915 struct gpio_desc *desc;
916 const char *name;
917 int ret;
918
919 if (!fwnode_property_present(fwnode, "gpio-hog"))
920 continue;
921
922 desc = acpi_gpiochip_parse_own_gpio(achip, fwnode, &name,
923 &lflags, &dflags);
924 if (IS_ERR(desc))
925 continue;
926
927 ret = gpiod_hog(desc, name, lflags, dflags);
928 if (ret) {
929 dev_err(chip->parent, "Failed to hog GPIO\n");
930 fwnode_handle_put(fwnode);
931 return;
932 }
933 }
934}
935
936void acpi_gpiochip_add(struct gpio_chip *chip)
937{
938 struct acpi_gpio_chip *acpi_gpio;
939 acpi_handle handle;
940 acpi_status status;
941
942 if (!chip || !chip->parent)
943 return;
944
945 handle = ACPI_HANDLE(chip->parent);
946 if (!handle)
947 return;
948
949 acpi_gpio = kzalloc(sizeof(*acpi_gpio), GFP_KERNEL);
950 if (!acpi_gpio) {
951 dev_err(chip->parent,
952 "Failed to allocate memory for ACPI GPIO chip\n");
953 return;
954 }
955
956 acpi_gpio->chip = chip;
957 INIT_LIST_HEAD(&acpi_gpio->events);
958
959 status = acpi_attach_data(handle, acpi_gpio_chip_dh, acpi_gpio);
960 if (ACPI_FAILURE(status)) {
961 dev_err(chip->parent, "Failed to attach ACPI GPIO chip\n");
962 kfree(acpi_gpio);
963 return;
964 }
965
966 if (!chip->names)
967 devprop_gpiochip_set_names(chip);
968
969 acpi_gpiochip_request_regions(acpi_gpio);
970 acpi_gpiochip_scan_gpios(acpi_gpio);
971 acpi_walk_dep_device_list(handle);
972}
973
974void acpi_gpiochip_remove(struct gpio_chip *chip)
975{
976 struct acpi_gpio_chip *acpi_gpio;
977 acpi_handle handle;
978 acpi_status status;
979
980 if (!chip || !chip->parent)
981 return;
982
983 handle = ACPI_HANDLE(chip->parent);
984 if (!handle)
985 return;
986
987 status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
988 if (ACPI_FAILURE(status)) {
989 dev_warn(chip->parent, "Failed to retrieve ACPI GPIO chip\n");
990 return;
991 }
992
993 acpi_gpiochip_free_regions(acpi_gpio);
994
995 acpi_detach_data(handle, acpi_gpio_chip_dh);
996 kfree(acpi_gpio);
997}
998
999static int acpi_gpio_package_count(const union acpi_object *obj)
1000{
1001 const union acpi_object *element = obj->package.elements;
1002 const union acpi_object *end = element + obj->package.count;
1003 unsigned int count = 0;
1004
1005 while (element < end) {
1006 switch (element->type) {
1007 case ACPI_TYPE_LOCAL_REFERENCE:
1008 element += 3;
1009 /* Fallthrough */
1010 case ACPI_TYPE_INTEGER:
1011 element++;
1012 count++;
1013 break;
1014
1015 default:
1016 return -EPROTO;
1017 }
1018 }
1019
1020 return count;
1021}
1022
1023static int acpi_find_gpio_count(struct acpi_resource *ares, void *data)
1024{
1025 unsigned int *count = data;
1026
1027 if (ares->type == ACPI_RESOURCE_TYPE_GPIO)
1028 *count += ares->data.gpio.pin_table_length;
1029
1030 return 1;
1031}
1032
1033/**
1034 * acpi_gpio_count - return the number of GPIOs associated with a
1035 * device / function or -ENOENT if no GPIO has been
1036 * assigned to the requested function.
1037 * @dev: GPIO consumer, can be NULL for system-global GPIOs
1038 * @con_id: function within the GPIO consumer
1039 */
1040int acpi_gpio_count(struct device *dev, const char *con_id)
1041{
1042 struct acpi_device *adev = ACPI_COMPANION(dev);
1043 const union acpi_object *obj;
1044 const struct acpi_gpio_mapping *gm;
1045 int count = -ENOENT;
1046 int ret;
1047 char propname[32];
1048 unsigned int i;
1049
1050 /* Try first from _DSD */
1051 for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
1052 if (con_id && strcmp(con_id, "gpios"))
1053 snprintf(propname, sizeof(propname), "%s-%s",
1054 con_id, gpio_suffixes[i]);
1055 else
1056 snprintf(propname, sizeof(propname), "%s",
1057 gpio_suffixes[i]);
1058
1059 ret = acpi_dev_get_property(adev, propname, ACPI_TYPE_ANY,
1060 &obj);
1061 if (ret == 0) {
1062 if (obj->type == ACPI_TYPE_LOCAL_REFERENCE)
1063 count = 1;
1064 else if (obj->type == ACPI_TYPE_PACKAGE)
1065 count = acpi_gpio_package_count(obj);
1066 } else if (adev->driver_gpios) {
1067 for (gm = adev->driver_gpios; gm->name; gm++)
1068 if (strcmp(propname, gm->name) == 0) {
1069 count = gm->size;
1070 break;
1071 }
1072 }
1073 if (count >= 0)
1074 break;
1075 }
1076
1077 /* Then from plain _CRS GPIOs */
1078 if (count < 0) {
1079 struct list_head resource_list;
1080 unsigned int crs_count = 0;
1081
1082 INIT_LIST_HEAD(&resource_list);
1083 acpi_dev_get_resources(adev, &resource_list,
1084 acpi_find_gpio_count, &crs_count);
1085 acpi_dev_free_resource_list(&resource_list);
1086 if (crs_count > 0)
1087 count = crs_count;
1088 }
1089 return count;
1090}
1091
1092struct acpi_crs_lookup {
1093 struct list_head node;
1094 struct acpi_device *adev;
1095 const char *con_id;
1096};
1097
1098static DEFINE_MUTEX(acpi_crs_lookup_lock);
1099static LIST_HEAD(acpi_crs_lookup_list);
1100
1101bool acpi_can_fallback_to_crs(struct acpi_device *adev, const char *con_id)
1102{
1103 struct acpi_crs_lookup *l, *lookup = NULL;
1104
1105 /* Never allow fallback if the device has properties */
1106 if (adev->data.properties || adev->driver_gpios)
1107 return false;
1108
1109 mutex_lock(&acpi_crs_lookup_lock);
1110
1111 list_for_each_entry(l, &acpi_crs_lookup_list, node) {
1112 if (l->adev == adev) {
1113 lookup = l;
1114 break;
1115 }
1116 }
1117
1118 if (!lookup) {
1119 lookup = kmalloc(sizeof(*lookup), GFP_KERNEL);
1120 if (lookup) {
1121 lookup->adev = adev;
1122 lookup->con_id = kstrdup(con_id, GFP_KERNEL);
1123 list_add_tail(&lookup->node, &acpi_crs_lookup_list);
1124 }
1125 }
1126
1127 mutex_unlock(&acpi_crs_lookup_lock);
1128
1129 return lookup &&
1130 ((!lookup->con_id && !con_id) ||
1131 (lookup->con_id && con_id &&
1132 strcmp(lookup->con_id, con_id) == 0));
1133}