1// SPDX-License-Identifier: GPL-2.0
2/*
3 * ACPI helpers for GPIO API
4 *
5 * Copyright (C) 2012, Intel Corporation
6 * Authors: Mathias Nyman <mathias.nyman@linux.intel.com>
7 * Mika Westerberg <mika.westerberg@linux.intel.com>
8 */
9
10#include <linux/errno.h>
11#include <linux/gpio/consumer.h>
12#include <linux/gpio/driver.h>
13#include <linux/gpio/machine.h>
14#include <linux/export.h>
15#include <linux/acpi.h>
16#include <linux/interrupt.h>
17#include <linux/mutex.h>
18#include <linux/pinctrl/pinctrl.h>
19
20#include "gpiolib.h"
21
22/**
23 * struct acpi_gpio_event - ACPI GPIO event handler data
24 *
25 * @node: list-entry of the events list of the struct acpi_gpio_chip
26 * @handle: handle of ACPI method to execute when the IRQ triggers
27 * @handler: irq_handler to pass to request_irq when requesting the IRQ
28 * @pin: GPIO pin number on the gpio_chip
29 * @irq: Linux IRQ number for the event, for request_ / free_irq
30 * @irqflags: flags to pass to request_irq when requesting the IRQ
31 * @irq_is_wake: If the ACPI flags indicate the IRQ is a wakeup source
32 * @irq_requested:True if request_irq has been done
33 * @desc: gpio_desc for the GPIO pin for this event
34 */
35struct acpi_gpio_event {
36 struct list_head node;
37 acpi_handle handle;
38 irq_handler_t handler;
39 unsigned int pin;
40 unsigned int irq;
41 unsigned long irqflags;
42 bool irq_is_wake;
43 bool irq_requested;
44 struct gpio_desc *desc;
45};
46
47struct acpi_gpio_connection {
48 struct list_head node;
49 unsigned int pin;
50 struct gpio_desc *desc;
51};
52
53struct acpi_gpio_chip {
54 /*
55 * ACPICA requires that the first field of the context parameter
56 * passed to acpi_install_address_space_handler() is large enough
57 * to hold struct acpi_connection_info.
58 */
59 struct acpi_connection_info conn_info;
60 struct list_head conns;
61 struct mutex conn_lock;
62 struct gpio_chip *chip;
63 struct list_head events;
64 struct list_head deferred_req_irqs_list_entry;
65};
66
67/*
68 * For gpiochips which call acpi_gpiochip_request_interrupts() before late_init
69 * (so builtin drivers) we register the ACPI GpioInt IRQ handlers from a
70 * late_initcall_sync handler, so that other builtin drivers can register their
71 * OpRegions before the event handlers can run. This list contains gpiochips
72 * for which the acpi_gpiochip_request_irqs() call has been deferred.
73 */
74static DEFINE_MUTEX(acpi_gpio_deferred_req_irqs_lock);
75static LIST_HEAD(acpi_gpio_deferred_req_irqs_list);
76static bool acpi_gpio_deferred_req_irqs_done;
77
78static int acpi_gpiochip_find(struct gpio_chip *gc, void *data)
79{
80 if (!gc->parent)
81 return false;
82
83 return ACPI_HANDLE(gc->parent) == data;
84}
85
86/**
87 * acpi_get_gpiod() - Translate ACPI GPIO pin to GPIO descriptor usable with GPIO API
88 * @path: ACPI GPIO controller full path name, (e.g. "\\_SB.GPO1")
89 * @pin: ACPI GPIO pin number (0-based, controller-relative)
90 *
91 * Return: GPIO descriptor to use with Linux generic GPIO API, or ERR_PTR
92 * error value. Specifically returns %-EPROBE_DEFER if the referenced GPIO
93 * controller does not have gpiochip registered at the moment. This is to
94 * support probe deferral.
95 */
96static struct gpio_desc *acpi_get_gpiod(char *path, int pin)
97{
98 struct gpio_chip *chip;
99 acpi_handle handle;
100 acpi_status status;
101
102 status = acpi_get_handle(NULL, path, &handle);
103 if (ACPI_FAILURE(status))
104 return ERR_PTR(-ENODEV);
105
106 chip = gpiochip_find(handle, acpi_gpiochip_find);
107 if (!chip)
108 return ERR_PTR(-EPROBE_DEFER);
109
110 return gpiochip_get_desc(chip, pin);
111}
112
113static irqreturn_t acpi_gpio_irq_handler(int irq, void *data)
114{
115 struct acpi_gpio_event *event = data;
116
117 acpi_evaluate_object(event->handle, NULL, NULL, NULL);
118
119 return IRQ_HANDLED;
120}
121
122static irqreturn_t acpi_gpio_irq_handler_evt(int irq, void *data)
123{
124 struct acpi_gpio_event *event = data;
125
126 acpi_execute_simple_method(event->handle, NULL, event->pin);
127
128 return IRQ_HANDLED;
129}
130
131static void acpi_gpio_chip_dh(acpi_handle handle, void *data)
132{
133 /* The address of this function is used as a key. */
134}
135
136bool acpi_gpio_get_irq_resource(struct acpi_resource *ares,
137 struct acpi_resource_gpio **agpio)
138{
139 struct acpi_resource_gpio *gpio;
140
141 if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
142 return false;
143
144 gpio = &ares->data.gpio;
145 if (gpio->connection_type != ACPI_RESOURCE_GPIO_TYPE_INT)
146 return false;
147
148 *agpio = gpio;
149 return true;
150}
151EXPORT_SYMBOL_GPL(acpi_gpio_get_irq_resource);
152
153static void acpi_gpiochip_request_irq(struct acpi_gpio_chip *acpi_gpio,
154 struct acpi_gpio_event *event)
155{
156 int ret, value;
157
158 ret = request_threaded_irq(event->irq, NULL, event->handler,
159 event->irqflags, "ACPI:Event", event);
160 if (ret) {
161 dev_err(acpi_gpio->chip->parent,
162 "Failed to setup interrupt handler for %d\n",
163 event->irq);
164 return;
165 }
166
167 if (event->irq_is_wake)
168 enable_irq_wake(event->irq);
169
170 event->irq_requested = true;
171
172 /* Make sure we trigger the initial state of edge-triggered IRQs */
173 value = gpiod_get_raw_value_cansleep(event->desc);
174 if (((event->irqflags & IRQF_TRIGGER_RISING) && value == 1) ||
175 ((event->irqflags & IRQF_TRIGGER_FALLING) && value == 0))
176 event->handler(event->irq, event);
177}
178
179static void acpi_gpiochip_request_irqs(struct acpi_gpio_chip *acpi_gpio)
180{
181 struct acpi_gpio_event *event;
182
183 list_for_each_entry(event, &acpi_gpio->events, node)
184 acpi_gpiochip_request_irq(acpi_gpio, event);
185}
186
187static acpi_status acpi_gpiochip_alloc_event(struct acpi_resource *ares,
188 void *context)
189{
190 struct acpi_gpio_chip *acpi_gpio = context;
191 struct gpio_chip *chip = acpi_gpio->chip;
192 struct acpi_resource_gpio *agpio;
193 acpi_handle handle, evt_handle;
194 struct acpi_gpio_event *event;
195 irq_handler_t handler = NULL;
196 struct gpio_desc *desc;
197 int ret, pin, irq;
198
199 if (!acpi_gpio_get_irq_resource(ares, &agpio))
200 return AE_OK;
201
202 handle = ACPI_HANDLE(chip->parent);
203 pin = agpio->pin_table[0];
204
205 if (pin <= 255) {
206 char ev_name[5];
207 sprintf(ev_name, "_%c%02hhX",
208 agpio->triggering == ACPI_EDGE_SENSITIVE ? 'E' : 'L',
209 pin);
210 if (ACPI_SUCCESS(acpi_get_handle(handle, ev_name, &evt_handle)))
211 handler = acpi_gpio_irq_handler;
212 }
213 if (!handler) {
214 if (ACPI_SUCCESS(acpi_get_handle(handle, "_EVT", &evt_handle)))
215 handler = acpi_gpio_irq_handler_evt;
216 }
217 if (!handler)
218 return AE_OK;
219
220 desc = gpiochip_request_own_desc(chip, pin, "ACPI:Event", 0);
221 if (IS_ERR(desc)) {
222 dev_err(chip->parent, "Failed to request GPIO\n");
223 return AE_ERROR;
224 }
225
226 gpiod_direction_input(desc);
227
228 ret = gpiochip_lock_as_irq(chip, pin);
229 if (ret) {
230 dev_err(chip->parent, "Failed to lock GPIO as interrupt\n");
231 goto fail_free_desc;
232 }
233
234 irq = gpiod_to_irq(desc);
235 if (irq < 0) {
236 dev_err(chip->parent, "Failed to translate GPIO to IRQ\n");
237 goto fail_unlock_irq;
238 }
239
240 event = kzalloc(sizeof(*event), GFP_KERNEL);
241 if (!event)
242 goto fail_unlock_irq;
243
244 event->irqflags = IRQF_ONESHOT;
245 if (agpio->triggering == ACPI_LEVEL_SENSITIVE) {
246 if (agpio->polarity == ACPI_ACTIVE_HIGH)
247 event->irqflags |= IRQF_TRIGGER_HIGH;
248 else
249 event->irqflags |= IRQF_TRIGGER_LOW;
250 } else {
251 switch (agpio->polarity) {
252 case ACPI_ACTIVE_HIGH:
253 event->irqflags |= IRQF_TRIGGER_RISING;
254 break;
255 case ACPI_ACTIVE_LOW:
256 event->irqflags |= IRQF_TRIGGER_FALLING;
257 break;
258 default:
259 event->irqflags |= IRQF_TRIGGER_RISING |
260 IRQF_TRIGGER_FALLING;
261 break;
262 }
263 }
264
265 event->handle = evt_handle;
266 event->handler = handler;
267 event->irq = irq;
268 event->irq_is_wake = agpio->wake_capable == ACPI_WAKE_CAPABLE;
269 event->pin = pin;
270 event->desc = desc;
271
272 list_add_tail(&event->node, &acpi_gpio->events);
273
274 return AE_OK;
275
276fail_unlock_irq:
277 gpiochip_unlock_as_irq(chip, pin);
278fail_free_desc:
279 gpiochip_free_own_desc(desc);
280
281 return AE_ERROR;
282}
283
284/**
285 * acpi_gpiochip_request_interrupts() - Register isr for gpio chip ACPI events
286 * @chip: GPIO chip
287 *
288 * ACPI5 platforms can use GPIO signaled ACPI events. These GPIO interrupts are
289 * handled by ACPI event methods which need to be called from the GPIO
290 * chip's interrupt handler. acpi_gpiochip_request_interrupts finds out which
291 * gpio pins have acpi event methods and assigns interrupt handlers that calls
292 * the acpi event methods for those pins.
293 */
294void acpi_gpiochip_request_interrupts(struct gpio_chip *chip)
295{
296 struct acpi_gpio_chip *acpi_gpio;
297 acpi_handle handle;
298 acpi_status status;
299 bool defer;
300
301 if (!chip->parent || !chip->to_irq)
302 return;
303
304 handle = ACPI_HANDLE(chip->parent);
305 if (!handle)
306 return;
307
308 status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
309 if (ACPI_FAILURE(status))
310 return;
311
312 acpi_walk_resources(handle, "_AEI",
313 acpi_gpiochip_alloc_event, acpi_gpio);
314
315 mutex_lock(&acpi_gpio_deferred_req_irqs_lock);
316 defer = !acpi_gpio_deferred_req_irqs_done;
317 if (defer)
318 list_add(&acpi_gpio->deferred_req_irqs_list_entry,
319 &acpi_gpio_deferred_req_irqs_list);
320 mutex_unlock(&acpi_gpio_deferred_req_irqs_lock);
321
322 if (defer)
323 return;
324
325 acpi_gpiochip_request_irqs(acpi_gpio);
326}
327EXPORT_SYMBOL_GPL(acpi_gpiochip_request_interrupts);
328
329/**
330 * acpi_gpiochip_free_interrupts() - Free GPIO ACPI event interrupts.
331 * @chip: GPIO chip
332 *
333 * Free interrupts associated with GPIO ACPI event method for the given
334 * GPIO chip.
335 */
336void acpi_gpiochip_free_interrupts(struct gpio_chip *chip)
337{
338 struct acpi_gpio_chip *acpi_gpio;
339 struct acpi_gpio_event *event, *ep;
340 acpi_handle handle;
341 acpi_status status;
342
343 if (!chip->parent || !chip->to_irq)
344 return;
345
346 handle = ACPI_HANDLE(chip->parent);
347 if (!handle)
348 return;
349
350 status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
351 if (ACPI_FAILURE(status))
352 return;
353
354 mutex_lock(&acpi_gpio_deferred_req_irqs_lock);
355 if (!list_empty(&acpi_gpio->deferred_req_irqs_list_entry))
356 list_del_init(&acpi_gpio->deferred_req_irqs_list_entry);
357 mutex_unlock(&acpi_gpio_deferred_req_irqs_lock);
358
359 list_for_each_entry_safe_reverse(event, ep, &acpi_gpio->events, node) {
360 if (event->irq_requested) {
361 if (event->irq_is_wake)
362 disable_irq_wake(event->irq);
363
364 free_irq(event->irq, event);
365 }
366
367 gpiochip_unlock_as_irq(chip, event->pin);
368 gpiochip_free_own_desc(event->desc);
369 list_del(&event->node);
370 kfree(event);
371 }
372}
373EXPORT_SYMBOL_GPL(acpi_gpiochip_free_interrupts);
374
375int acpi_dev_add_driver_gpios(struct acpi_device *adev,
376 const struct acpi_gpio_mapping *gpios)
377{
378 if (adev && gpios) {
379 adev->driver_gpios = gpios;
380 return 0;
381 }
382 return -EINVAL;
383}
384EXPORT_SYMBOL_GPL(acpi_dev_add_driver_gpios);
385
386static void devm_acpi_dev_release_driver_gpios(struct device *dev, void *res)
387{
388 acpi_dev_remove_driver_gpios(ACPI_COMPANION(dev));
389}
390
391int devm_acpi_dev_add_driver_gpios(struct device *dev,
392 const struct acpi_gpio_mapping *gpios)
393{
394 void *res;
395 int ret;
396
397 res = devres_alloc(devm_acpi_dev_release_driver_gpios, 0, GFP_KERNEL);
398 if (!res)
399 return -ENOMEM;
400
401 ret = acpi_dev_add_driver_gpios(ACPI_COMPANION(dev), gpios);
402 if (ret) {
403 devres_free(res);
404 return ret;
405 }
406 devres_add(dev, res);
407 return 0;
408}
409EXPORT_SYMBOL_GPL(devm_acpi_dev_add_driver_gpios);
410
411void devm_acpi_dev_remove_driver_gpios(struct device *dev)
412{
413 WARN_ON(devres_release(dev, devm_acpi_dev_release_driver_gpios, NULL, NULL));
414}
415EXPORT_SYMBOL_GPL(devm_acpi_dev_remove_driver_gpios);
416
417static bool acpi_get_driver_gpio_data(struct acpi_device *adev,
418 const char *name, int index,
419 struct fwnode_reference_args *args,
420 unsigned int *quirks)
421{
422 const struct acpi_gpio_mapping *gm;
423
424 if (!adev->driver_gpios)
425 return false;
426
427 for (gm = adev->driver_gpios; gm->name; gm++)
428 if (!strcmp(name, gm->name) && gm->data && index < gm->size) {
429 const struct acpi_gpio_params *par = gm->data + index;
430
431 args->fwnode = acpi_fwnode_handle(adev);
432 args->args[0] = par->crs_entry_index;
433 args->args[1] = par->line_index;
434 args->args[2] = par->active_low;
435 args->nargs = 3;
436
437 *quirks = gm->quirks;
438 return true;
439 }
440
441 return false;
442}
443
444static enum gpiod_flags
445acpi_gpio_to_gpiod_flags(const struct acpi_resource_gpio *agpio)
446{
447 bool pull_up = agpio->pin_config == ACPI_PIN_CONFIG_PULLUP;
448
449 switch (agpio->io_restriction) {
450 case ACPI_IO_RESTRICT_INPUT:
451 return GPIOD_IN;
452 case ACPI_IO_RESTRICT_OUTPUT:
453 /*
454 * ACPI GPIO resources don't contain an initial value for the
455 * GPIO. Therefore we deduce that value from the pull field
456 * instead. If the pin is pulled up we assume default to be
457 * high, otherwise low.
458 */
459 return pull_up ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW;
460 default:
461 /*
462 * Assume that the BIOS has configured the direction and pull
463 * accordingly.
464 */
465 return GPIOD_ASIS;
466 }
467}
468
469static int
470__acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags, enum gpiod_flags update)
471{
472 const enum gpiod_flags mask =
473 GPIOD_FLAGS_BIT_DIR_SET | GPIOD_FLAGS_BIT_DIR_OUT |
474 GPIOD_FLAGS_BIT_DIR_VAL;
475 int ret = 0;
476
477 /*
478 * Check if the BIOS has IoRestriction with explicitly set direction
479 * and update @flags accordingly. Otherwise use whatever caller asked
480 * for.
481 */
482 if (update & GPIOD_FLAGS_BIT_DIR_SET) {
483 enum gpiod_flags diff = *flags ^ update;
484
485 /*
486 * Check if caller supplied incompatible GPIO initialization
487 * flags.
488 *
489 * Return %-EINVAL to notify that firmware has different
490 * settings and we are going to use them.
491 */
492 if (((*flags & GPIOD_FLAGS_BIT_DIR_SET) && (diff & GPIOD_FLAGS_BIT_DIR_OUT)) ||
493 ((*flags & GPIOD_FLAGS_BIT_DIR_OUT) && (diff & GPIOD_FLAGS_BIT_DIR_VAL)))
494 ret = -EINVAL;
495 *flags = (*flags & ~mask) | (update & mask);
496 }
497 return ret;
498}
499
500int
501acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags, struct acpi_gpio_info *info)
502{
503 struct device *dev = &info->adev->dev;
504 enum gpiod_flags old = *flags;
505 int ret;
506
507 ret = __acpi_gpio_update_gpiod_flags(&old, info->flags);
508 if (info->quirks & ACPI_GPIO_QUIRK_NO_IO_RESTRICTION) {
509 if (ret)
510 dev_warn(dev, FW_BUG "GPIO not in correct mode, fixing\n");
511 } else {
512 if (ret)
513 dev_dbg(dev, "Override GPIO initialization flags\n");
514 *flags = old;
515 }
516
517 return ret;
518}
519
520struct acpi_gpio_lookup {
521 struct acpi_gpio_info info;
522 int index;
523 int pin_index;
524 bool active_low;
525 struct gpio_desc *desc;
526 int n;
527};
528
529static int acpi_populate_gpio_lookup(struct acpi_resource *ares, void *data)
530{
531 struct acpi_gpio_lookup *lookup = data;
532
533 if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
534 return 1;
535
536 if (!lookup->desc) {
537 const struct acpi_resource_gpio *agpio = &ares->data.gpio;
538 bool gpioint = agpio->connection_type == ACPI_RESOURCE_GPIO_TYPE_INT;
539 int pin_index;
540
541 if (lookup->info.quirks & ACPI_GPIO_QUIRK_ONLY_GPIOIO && gpioint)
542 lookup->index++;
543
544 if (lookup->n++ != lookup->index)
545 return 1;
546
547 pin_index = lookup->pin_index;
548 if (pin_index >= agpio->pin_table_length)
549 return 1;
550
551 lookup->desc = acpi_get_gpiod(agpio->resource_source.string_ptr,
552 agpio->pin_table[pin_index]);
553 lookup->info.gpioint = gpioint;
554
555 /*
556 * Polarity and triggering are only specified for GpioInt
557 * resource.
558 * Note: we expect here:
559 * - ACPI_ACTIVE_LOW == GPIO_ACTIVE_LOW
560 * - ACPI_ACTIVE_HIGH == GPIO_ACTIVE_HIGH
561 */
562 if (lookup->info.gpioint) {
563 lookup->info.flags = GPIOD_IN;
564 lookup->info.polarity = agpio->polarity;
565 lookup->info.triggering = agpio->triggering;
566 } else {
567 lookup->info.flags = acpi_gpio_to_gpiod_flags(agpio);
568 lookup->info.polarity = lookup->active_low;
569 }
570 }
571
572 return 1;
573}
574
575static int acpi_gpio_resource_lookup(struct acpi_gpio_lookup *lookup,
576 struct acpi_gpio_info *info)
577{
578 struct acpi_device *adev = lookup->info.adev;
579 struct list_head res_list;
580 int ret;
581
582 INIT_LIST_HEAD(&res_list);
583
584 ret = acpi_dev_get_resources(adev, &res_list,
585 acpi_populate_gpio_lookup,
586 lookup);
587 if (ret < 0)
588 return ret;
589
590 acpi_dev_free_resource_list(&res_list);
591
592 if (!lookup->desc)
593 return -ENOENT;
594
595 if (info)
596 *info = lookup->info;
597 return 0;
598}
599
600static int acpi_gpio_property_lookup(struct fwnode_handle *fwnode,
601 const char *propname, int index,
602 struct acpi_gpio_lookup *lookup)
603{
604 struct fwnode_reference_args args;
605 unsigned int quirks = 0;
606 int ret;
607
608 memset(&args, 0, sizeof(args));
609 ret = __acpi_node_get_property_reference(fwnode, propname, index, 3,
610 &args);
611 if (ret) {
612 struct acpi_device *adev = to_acpi_device_node(fwnode);
613
614 if (!adev)
615 return ret;
616
617 if (!acpi_get_driver_gpio_data(adev, propname, index, &args,
618 &quirks))
619 return ret;
620 }
621 /*
622 * The property was found and resolved, so need to lookup the GPIO based
623 * on returned args.
624 */
625 if (!to_acpi_device_node(args.fwnode))
626 return -EINVAL;
627 if (args.nargs != 3)
628 return -EPROTO;
629
630 lookup->index = args.args[0];
631 lookup->pin_index = args.args[1];
632 lookup->active_low = !!args.args[2];
633
634 lookup->info.adev = to_acpi_device_node(args.fwnode);
635 lookup->info.quirks = quirks;
636
637 return 0;
638}
639
640/**
641 * acpi_get_gpiod_by_index() - get a GPIO descriptor from device resources
642 * @adev: pointer to a ACPI device to get GPIO from
643 * @propname: Property name of the GPIO (optional)
644 * @index: index of GpioIo/GpioInt resource (starting from %0)
645 * @info: info pointer to fill in (optional)
646 *
647 * Function goes through ACPI resources for @adev and based on @index looks
648 * up a GpioIo/GpioInt resource, translates it to the Linux GPIO descriptor,
649 * and returns it. @index matches GpioIo/GpioInt resources only so if there
650 * are total %3 GPIO resources, the index goes from %0 to %2.
651 *
652 * If @propname is specified the GPIO is looked using device property. In
653 * that case @index is used to select the GPIO entry in the property value
654 * (in case of multiple).
655 *
656 * If the GPIO cannot be translated or there is an error an ERR_PTR is
657 * returned.
658 *
659 * Note: if the GPIO resource has multiple entries in the pin list, this
660 * function only returns the first.
661 */
662static struct gpio_desc *acpi_get_gpiod_by_index(struct acpi_device *adev,
663 const char *propname, int index,
664 struct acpi_gpio_info *info)
665{
666 struct acpi_gpio_lookup lookup;
667 int ret;
668
669 if (!adev)
670 return ERR_PTR(-ENODEV);
671
672 memset(&lookup, 0, sizeof(lookup));
673 lookup.index = index;
674
675 if (propname) {
676 dev_dbg(&adev->dev, "GPIO: looking up %s\n", propname);
677
678 ret = acpi_gpio_property_lookup(acpi_fwnode_handle(adev),
679 propname, index, &lookup);
680 if (ret)
681 return ERR_PTR(ret);
682
683 dev_dbg(&adev->dev, "GPIO: _DSD returned %s %d %d %u\n",
684 dev_name(&lookup.info.adev->dev), lookup.index,
685 lookup.pin_index, lookup.active_low);
686 } else {
687 dev_dbg(&adev->dev, "GPIO: looking up %d in _CRS\n", index);
688 lookup.info.adev = adev;
689 }
690
691 ret = acpi_gpio_resource_lookup(&lookup, info);
692 return ret ? ERR_PTR(ret) : lookup.desc;
693}
694
695struct gpio_desc *acpi_find_gpio(struct device *dev,
696 const char *con_id,
697 unsigned int idx,
698 enum gpiod_flags *dflags,
699 enum gpio_lookup_flags *lookupflags)
700{
701 struct acpi_device *adev = ACPI_COMPANION(dev);
702 struct acpi_gpio_info info;
703 struct gpio_desc *desc;
704 char propname[32];
705 int i;
706
707 /* Try first from _DSD */
708 for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
709 if (con_id) {
710 snprintf(propname, sizeof(propname), "%s-%s",
711 con_id, gpio_suffixes[i]);
712 } else {
713 snprintf(propname, sizeof(propname), "%s",
714 gpio_suffixes[i]);
715 }
716
717 desc = acpi_get_gpiod_by_index(adev, propname, idx, &info);
718 if (!IS_ERR(desc))
719 break;
720 if (PTR_ERR(desc) == -EPROBE_DEFER)
721 return ERR_CAST(desc);
722 }
723
724 /* Then from plain _CRS GPIOs */
725 if (IS_ERR(desc)) {
726 if (!acpi_can_fallback_to_crs(adev, con_id))
727 return ERR_PTR(-ENOENT);
728
729 desc = acpi_get_gpiod_by_index(adev, NULL, idx, &info);
730 if (IS_ERR(desc))
731 return desc;
732 }
733
734 if (info.gpioint &&
735 (*dflags == GPIOD_OUT_LOW || *dflags == GPIOD_OUT_HIGH)) {
736 dev_dbg(dev, "refusing GpioInt() entry when doing GPIOD_OUT_* lookup\n");
737 return ERR_PTR(-ENOENT);
738 }
739
740 if (info.polarity == GPIO_ACTIVE_LOW)
741 *lookupflags |= GPIO_ACTIVE_LOW;
742
743 acpi_gpio_update_gpiod_flags(dflags, &info);
744 return desc;
745}
746
747/**
748 * acpi_node_get_gpiod() - get a GPIO descriptor from ACPI resources
749 * @fwnode: pointer to an ACPI firmware node to get the GPIO information from
750 * @propname: Property name of the GPIO
751 * @index: index of GpioIo/GpioInt resource (starting from %0)
752 * @info: info pointer to fill in (optional)
753 *
754 * If @fwnode is an ACPI device object, call %acpi_get_gpiod_by_index() for it.
755 * Otherwise (ie. it is a data-only non-device object), use the property-based
756 * GPIO lookup to get to the GPIO resource with the relevant information and use
757 * that to obtain the GPIO descriptor to return.
758 */
759struct gpio_desc *acpi_node_get_gpiod(struct fwnode_handle *fwnode,
760 const char *propname, int index,
761 struct acpi_gpio_info *info)
762{
763 struct acpi_gpio_lookup lookup;
764 struct acpi_device *adev;
765 int ret;
766
767 adev = to_acpi_device_node(fwnode);
768 if (adev)
769 return acpi_get_gpiod_by_index(adev, propname, index, info);
770
771 if (!is_acpi_data_node(fwnode))
772 return ERR_PTR(-ENODEV);
773
774 if (!propname)
775 return ERR_PTR(-EINVAL);
776
777 memset(&lookup, 0, sizeof(lookup));
778 lookup.index = index;
779
780 ret = acpi_gpio_property_lookup(fwnode, propname, index, &lookup);
781 if (ret)
782 return ERR_PTR(ret);
783
784 ret = acpi_gpio_resource_lookup(&lookup, info);
785 return ret ? ERR_PTR(ret) : lookup.desc;
786}
787
788/**
789 * acpi_dev_gpio_irq_get() - Find GpioInt and translate it to Linux IRQ number
790 * @adev: pointer to a ACPI device to get IRQ from
791 * @index: index of GpioInt resource (starting from %0)
792 *
793 * If the device has one or more GpioInt resources, this function can be
794 * used to translate from the GPIO offset in the resource to the Linux IRQ
795 * number.
796 *
797 * The function is idempotent, though each time it runs it will configure GPIO
798 * pin direction according to the flags in GpioInt resource.
799 *
800 * Return: Linux IRQ number (> %0) on success, negative errno on failure.
801 */
802int acpi_dev_gpio_irq_get(struct acpi_device *adev, int index)
803{
804 int idx, i;
805 unsigned int irq_flags;
806 int ret;
807
808 for (i = 0, idx = 0; idx <= index; i++) {
809 struct acpi_gpio_info info;
810 struct gpio_desc *desc;
811
812 desc = acpi_get_gpiod_by_index(adev, NULL, i, &info);
813
814 /* Ignore -EPROBE_DEFER, it only matters if idx matches */
815 if (IS_ERR(desc) && PTR_ERR(desc) != -EPROBE_DEFER)
816 return PTR_ERR(desc);
817
818 if (info.gpioint && idx++ == index) {
819 char label[32];
820 int irq;
821
822 if (IS_ERR(desc))
823 return PTR_ERR(desc);
824
825 irq = gpiod_to_irq(desc);
826 if (irq < 0)
827 return irq;
828
829 snprintf(label, sizeof(label), "GpioInt() %d", index);
830 ret = gpiod_configure_flags(desc, label, 0, info.flags);
831 if (ret < 0)
832 return ret;
833
834 irq_flags = acpi_dev_get_irq_type(info.triggering,
835 info.polarity);
836
837 /* Set type if specified and different than the current one */
838 if (irq_flags != IRQ_TYPE_NONE &&
839 irq_flags != irq_get_trigger_type(irq))
840 irq_set_irq_type(irq, irq_flags);
841
842 return irq;
843 }
844
845 }
846 return -ENOENT;
847}
848EXPORT_SYMBOL_GPL(acpi_dev_gpio_irq_get);
849
850static acpi_status
851acpi_gpio_adr_space_handler(u32 function, acpi_physical_address address,
852 u32 bits, u64 *value, void *handler_context,
853 void *region_context)
854{
855 struct acpi_gpio_chip *achip = region_context;
856 struct gpio_chip *chip = achip->chip;
857 struct acpi_resource_gpio *agpio;
858 struct acpi_resource *ares;
859 int pin_index = (int)address;
860 acpi_status status;
861 int length;
862 int i;
863
864 status = acpi_buffer_to_resource(achip->conn_info.connection,
865 achip->conn_info.length, &ares);
866 if (ACPI_FAILURE(status))
867 return status;
868
869 if (WARN_ON(ares->type != ACPI_RESOURCE_TYPE_GPIO)) {
870 ACPI_FREE(ares);
871 return AE_BAD_PARAMETER;
872 }
873
874 agpio = &ares->data.gpio;
875
876 if (WARN_ON(agpio->io_restriction == ACPI_IO_RESTRICT_INPUT &&
877 function == ACPI_WRITE)) {
878 ACPI_FREE(ares);
879 return AE_BAD_PARAMETER;
880 }
881
882 length = min(agpio->pin_table_length, (u16)(pin_index + bits));
883 for (i = pin_index; i < length; ++i) {
884 int pin = agpio->pin_table[i];
885 struct acpi_gpio_connection *conn;
886 struct gpio_desc *desc;
887 bool found;
888
889 mutex_lock(&achip->conn_lock);
890
891 found = false;
892 list_for_each_entry(conn, &achip->conns, node) {
893 if (conn->pin == pin) {
894 found = true;
895 desc = conn->desc;
896 break;
897 }
898 }
899
900 /*
901 * The same GPIO can be shared between operation region and
902 * event but only if the access here is ACPI_READ. In that
903 * case we "borrow" the event GPIO instead.
904 */
905 if (!found && agpio->shareable == ACPI_SHARED &&
906 function == ACPI_READ) {
907 struct acpi_gpio_event *event;
908
909 list_for_each_entry(event, &achip->events, node) {
910 if (event->pin == pin) {
911 desc = event->desc;
912 found = true;
913 break;
914 }
915 }
916 }
917
918 if (!found) {
919 enum gpiod_flags flags = acpi_gpio_to_gpiod_flags(agpio);
920 const char *label = "ACPI:OpRegion";
921
922 desc = gpiochip_request_own_desc(chip, pin, label,
923 flags);
924 if (IS_ERR(desc)) {
925 status = AE_ERROR;
926 mutex_unlock(&achip->conn_lock);
927 goto out;
928 }
929
930 conn = kzalloc(sizeof(*conn), GFP_KERNEL);
931 if (!conn) {
932 status = AE_NO_MEMORY;
933 gpiochip_free_own_desc(desc);
934 mutex_unlock(&achip->conn_lock);
935 goto out;
936 }
937
938 conn->pin = pin;
939 conn->desc = desc;
940 list_add_tail(&conn->node, &achip->conns);
941 }
942
943 mutex_unlock(&achip->conn_lock);
944
945 if (function == ACPI_WRITE)
946 gpiod_set_raw_value_cansleep(desc,
947 !!((1 << i) & *value));
948 else
949 *value |= (u64)gpiod_get_raw_value_cansleep(desc) << i;
950 }
951
952out:
953 ACPI_FREE(ares);
954 return status;
955}
956
957static void acpi_gpiochip_request_regions(struct acpi_gpio_chip *achip)
958{
959 struct gpio_chip *chip = achip->chip;
960 acpi_handle handle = ACPI_HANDLE(chip->parent);
961 acpi_status status;
962
963 INIT_LIST_HEAD(&achip->conns);
964 mutex_init(&achip->conn_lock);
965 status = acpi_install_address_space_handler(handle, ACPI_ADR_SPACE_GPIO,
966 acpi_gpio_adr_space_handler,
967 NULL, achip);
968 if (ACPI_FAILURE(status))
969 dev_err(chip->parent,
970 "Failed to install GPIO OpRegion handler\n");
971}
972
973static void acpi_gpiochip_free_regions(struct acpi_gpio_chip *achip)
974{
975 struct gpio_chip *chip = achip->chip;
976 acpi_handle handle = ACPI_HANDLE(chip->parent);
977 struct acpi_gpio_connection *conn, *tmp;
978 acpi_status status;
979
980 status = acpi_remove_address_space_handler(handle, ACPI_ADR_SPACE_GPIO,
981 acpi_gpio_adr_space_handler);
982 if (ACPI_FAILURE(status)) {
983 dev_err(chip->parent,
984 "Failed to remove GPIO OpRegion handler\n");
985 return;
986 }
987
988 list_for_each_entry_safe_reverse(conn, tmp, &achip->conns, node) {
989 gpiochip_free_own_desc(conn->desc);
990 list_del(&conn->node);
991 kfree(conn);
992 }
993}
994
995static struct gpio_desc *acpi_gpiochip_parse_own_gpio(
996 struct acpi_gpio_chip *achip, struct fwnode_handle *fwnode,
997 const char **name, unsigned int *lflags, unsigned int *dflags)
998{
999 struct gpio_chip *chip = achip->chip;
1000 struct gpio_desc *desc;
1001 u32 gpios[2];
1002 int ret;
1003
1004 *lflags = 0;
1005 *dflags = 0;
1006 *name = NULL;
1007
1008 ret = fwnode_property_read_u32_array(fwnode, "gpios", gpios,
1009 ARRAY_SIZE(gpios));
1010 if (ret < 0)
1011 return ERR_PTR(ret);
1012
1013 desc = gpiochip_get_desc(chip, gpios[0]);
1014 if (IS_ERR(desc))
1015 return desc;
1016
1017 if (gpios[1])
1018 *lflags |= GPIO_ACTIVE_LOW;
1019
1020 if (fwnode_property_present(fwnode, "input"))
1021 *dflags |= GPIOD_IN;
1022 else if (fwnode_property_present(fwnode, "output-low"))
1023 *dflags |= GPIOD_OUT_LOW;
1024 else if (fwnode_property_present(fwnode, "output-high"))
1025 *dflags |= GPIOD_OUT_HIGH;
1026 else
1027 return ERR_PTR(-EINVAL);
1028
1029 fwnode_property_read_string(fwnode, "line-name", name);
1030
1031 return desc;
1032}
1033
1034static void acpi_gpiochip_scan_gpios(struct acpi_gpio_chip *achip)
1035{
1036 struct gpio_chip *chip = achip->chip;
1037 struct fwnode_handle *fwnode;
1038
1039 device_for_each_child_node(chip->parent, fwnode) {
1040 unsigned int lflags, dflags;
1041 struct gpio_desc *desc;
1042 const char *name;
1043 int ret;
1044
1045 if (!fwnode_property_present(fwnode, "gpio-hog"))
1046 continue;
1047
1048 desc = acpi_gpiochip_parse_own_gpio(achip, fwnode, &name,
1049 &lflags, &dflags);
1050 if (IS_ERR(desc))
1051 continue;
1052
1053 ret = gpiod_hog(desc, name, lflags, dflags);
1054 if (ret) {
1055 dev_err(chip->parent, "Failed to hog GPIO\n");
1056 fwnode_handle_put(fwnode);
1057 return;
1058 }
1059 }
1060}
1061
1062void acpi_gpiochip_add(struct gpio_chip *chip)
1063{
1064 struct acpi_gpio_chip *acpi_gpio;
1065 acpi_handle handle;
1066 acpi_status status;
1067
1068 if (!chip || !chip->parent)
1069 return;
1070
1071 handle = ACPI_HANDLE(chip->parent);
1072 if (!handle)
1073 return;
1074
1075 acpi_gpio = kzalloc(sizeof(*acpi_gpio), GFP_KERNEL);
1076 if (!acpi_gpio) {
1077 dev_err(chip->parent,
1078 "Failed to allocate memory for ACPI GPIO chip\n");
1079 return;
1080 }
1081
1082 acpi_gpio->chip = chip;
1083 INIT_LIST_HEAD(&acpi_gpio->events);
1084 INIT_LIST_HEAD(&acpi_gpio->deferred_req_irqs_list_entry);
1085
1086 status = acpi_attach_data(handle, acpi_gpio_chip_dh, acpi_gpio);
1087 if (ACPI_FAILURE(status)) {
1088 dev_err(chip->parent, "Failed to attach ACPI GPIO chip\n");
1089 kfree(acpi_gpio);
1090 return;
1091 }
1092
1093 if (!chip->names)
1094 devprop_gpiochip_set_names(chip, dev_fwnode(chip->parent));
1095
1096 acpi_gpiochip_request_regions(acpi_gpio);
1097 acpi_gpiochip_scan_gpios(acpi_gpio);
1098 acpi_walk_dep_device_list(handle);
1099}
1100
1101void acpi_gpiochip_remove(struct gpio_chip *chip)
1102{
1103 struct acpi_gpio_chip *acpi_gpio;
1104 acpi_handle handle;
1105 acpi_status status;
1106
1107 if (!chip || !chip->parent)
1108 return;
1109
1110 handle = ACPI_HANDLE(chip->parent);
1111 if (!handle)
1112 return;
1113
1114 status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
1115 if (ACPI_FAILURE(status)) {
1116 dev_warn(chip->parent, "Failed to retrieve ACPI GPIO chip\n");
1117 return;
1118 }
1119
1120 acpi_gpiochip_free_regions(acpi_gpio);
1121
1122 acpi_detach_data(handle, acpi_gpio_chip_dh);
1123 kfree(acpi_gpio);
1124}
1125
1126static int acpi_gpio_package_count(const union acpi_object *obj)
1127{
1128 const union acpi_object *element = obj->package.elements;
1129 const union acpi_object *end = element + obj->package.count;
1130 unsigned int count = 0;
1131
1132 while (element < end) {
1133 switch (element->type) {
1134 case ACPI_TYPE_LOCAL_REFERENCE:
1135 element += 3;
1136 /* Fallthrough */
1137 case ACPI_TYPE_INTEGER:
1138 element++;
1139 count++;
1140 break;
1141
1142 default:
1143 return -EPROTO;
1144 }
1145 }
1146
1147 return count;
1148}
1149
1150static int acpi_find_gpio_count(struct acpi_resource *ares, void *data)
1151{
1152 unsigned int *count = data;
1153
1154 if (ares->type == ACPI_RESOURCE_TYPE_GPIO)
1155 *count += ares->data.gpio.pin_table_length;
1156
1157 return 1;
1158}
1159
1160/**
1161 * acpi_gpio_count - return the number of GPIOs associated with a
1162 * device / function or -ENOENT if no GPIO has been
1163 * assigned to the requested function.
1164 * @dev: GPIO consumer, can be NULL for system-global GPIOs
1165 * @con_id: function within the GPIO consumer
1166 */
1167int acpi_gpio_count(struct device *dev, const char *con_id)
1168{
1169 struct acpi_device *adev = ACPI_COMPANION(dev);
1170 const union acpi_object *obj;
1171 const struct acpi_gpio_mapping *gm;
1172 int count = -ENOENT;
1173 int ret;
1174 char propname[32];
1175 unsigned int i;
1176
1177 /* Try first from _DSD */
1178 for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
1179 if (con_id)
1180 snprintf(propname, sizeof(propname), "%s-%s",
1181 con_id, gpio_suffixes[i]);
1182 else
1183 snprintf(propname, sizeof(propname), "%s",
1184 gpio_suffixes[i]);
1185
1186 ret = acpi_dev_get_property(adev, propname, ACPI_TYPE_ANY,
1187 &obj);
1188 if (ret == 0) {
1189 if (obj->type == ACPI_TYPE_LOCAL_REFERENCE)
1190 count = 1;
1191 else if (obj->type == ACPI_TYPE_PACKAGE)
1192 count = acpi_gpio_package_count(obj);
1193 } else if (adev->driver_gpios) {
1194 for (gm = adev->driver_gpios; gm->name; gm++)
1195 if (strcmp(propname, gm->name) == 0) {
1196 count = gm->size;
1197 break;
1198 }
1199 }
1200 if (count > 0)
1201 break;
1202 }
1203
1204 /* Then from plain _CRS GPIOs */
1205 if (count < 0) {
1206 struct list_head resource_list;
1207 unsigned int crs_count = 0;
1208
1209 if (!acpi_can_fallback_to_crs(adev, con_id))
1210 return count;
1211
1212 INIT_LIST_HEAD(&resource_list);
1213 acpi_dev_get_resources(adev, &resource_list,
1214 acpi_find_gpio_count, &crs_count);
1215 acpi_dev_free_resource_list(&resource_list);
1216 if (crs_count > 0)
1217 count = crs_count;
1218 }
1219 return count ? count : -ENOENT;
1220}
1221
1222bool acpi_can_fallback_to_crs(struct acpi_device *adev, const char *con_id)
1223{
1224 /* Never allow fallback if the device has properties */
1225 if (acpi_dev_has_props(adev) || adev->driver_gpios)
1226 return false;
1227
1228 return con_id == NULL;
1229}
1230
1231/* Run deferred acpi_gpiochip_request_irqs() */
1232static int acpi_gpio_handle_deferred_request_irqs(void)
1233{
1234 struct acpi_gpio_chip *acpi_gpio, *tmp;
1235
1236 mutex_lock(&acpi_gpio_deferred_req_irqs_lock);
1237 list_for_each_entry_safe(acpi_gpio, tmp,
1238 &acpi_gpio_deferred_req_irqs_list,
1239 deferred_req_irqs_list_entry)
1240 acpi_gpiochip_request_irqs(acpi_gpio);
1241
1242 acpi_gpio_deferred_req_irqs_done = true;
1243 mutex_unlock(&acpi_gpio_deferred_req_irqs_lock);
1244
1245 return 0;
1246}
1247/* We must use _sync so that this runs after the first deferred_probe run */
1248late_initcall_sync(acpi_gpio_handle_deferred_request_irqs);
1249