1 // SPDX-License-Identifier: GPL-2.0
3 * ACPI helpers for GPIO API
5 * Copyright (C) 2012, Intel Corporation
6 * Authors: Mathias Nyman <mathias.nyman@linux.intel.com>
7 * Mika Westerberg <mika.westerberg@linux.intel.com>
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>
23 * struct acpi_gpio_event - ACPI GPIO event handler data
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 * @is_requested: True if request_irq has been done
33 * @desc: gpio_desc for the GPIO pin for this event
35 struct acpi_gpio_event {
36 struct list_head node;
38 irq_handler_t handler;
41 unsigned long irqflags;
44 struct gpio_desc *desc;
47 struct acpi_gpio_connection {
48 struct list_head node;
50 struct gpio_desc *desc;
53 struct acpi_gpio_chip {
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.
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;
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.
74 static DEFINE_MUTEX(acpi_gpio_deferred_req_irqs_lock);
75 static LIST_HEAD(acpi_gpio_deferred_req_irqs_list);
76 static bool acpi_gpio_deferred_req_irqs_done;
78 static int acpi_gpiochip_find(struct gpio_chip *gc, void *data)
83 return ACPI_HANDLE(gc->parent) == data;
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)
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.
96 static struct gpio_desc *acpi_get_gpiod(char *path, int pin)
98 struct gpio_chip *chip;
102 status = acpi_get_handle(NULL, path, &handle);
103 if (ACPI_FAILURE(status))
104 return ERR_PTR(-ENODEV);
106 chip = gpiochip_find(handle, acpi_gpiochip_find);
108 return ERR_PTR(-EPROBE_DEFER);
110 return gpiochip_get_desc(chip, pin);
113 static irqreturn_t acpi_gpio_irq_handler(int irq, void *data)
115 struct acpi_gpio_event *event = data;
117 acpi_evaluate_object(event->handle, NULL, NULL, NULL);
122 static irqreturn_t acpi_gpio_irq_handler_evt(int irq, void *data)
124 struct acpi_gpio_event *event = data;
126 acpi_execute_simple_method(event->handle, NULL, event->pin);
131 static void acpi_gpio_chip_dh(acpi_handle handle, void *data)
133 /* The address of this function is used as a key. */
136 bool acpi_gpio_get_irq_resource(struct acpi_resource *ares,
137 struct acpi_resource_gpio **agpio)
139 struct acpi_resource_gpio *gpio;
141 if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
144 gpio = &ares->data.gpio;
145 if (gpio->connection_type != ACPI_RESOURCE_GPIO_TYPE_INT)
151 EXPORT_SYMBOL_GPL(acpi_gpio_get_irq_resource);
153 static void acpi_gpiochip_request_irq(struct acpi_gpio_chip *acpi_gpio,
154 struct acpi_gpio_event *event)
158 ret = request_threaded_irq(event->irq, NULL, event->handler,
159 event->irqflags, "ACPI:Event", event);
161 dev_err(acpi_gpio->chip->parent,
162 "Failed to setup interrupt handler for %d\n",
167 if (event->irq_is_wake)
168 enable_irq_wake(event->irq);
170 event->irq_requested = true;
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);
179 static void acpi_gpiochip_request_irqs(struct acpi_gpio_chip *acpi_gpio)
181 struct acpi_gpio_event *event;
183 list_for_each_entry(event, &acpi_gpio->events, node)
184 acpi_gpiochip_request_irq(acpi_gpio, event);
187 static acpi_status acpi_gpiochip_alloc_event(struct acpi_resource *ares,
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;
199 if (!acpi_gpio_get_irq_resource(ares, &agpio))
202 handle = ACPI_HANDLE(chip->parent);
203 pin = agpio->pin_table[0];
207 sprintf(ev_name, "_%c%02hhX",
208 agpio->triggering == ACPI_EDGE_SENSITIVE ? 'E' : 'L',
210 if (ACPI_SUCCESS(acpi_get_handle(handle, ev_name, &evt_handle)))
211 handler = acpi_gpio_irq_handler;
214 if (ACPI_SUCCESS(acpi_get_handle(handle, "_EVT", &evt_handle)))
215 handler = acpi_gpio_irq_handler_evt;
220 desc = gpiochip_request_own_desc(chip, pin, "ACPI:Event");
222 dev_err(chip->parent, "Failed to request GPIO\n");
226 gpiod_direction_input(desc);
228 ret = gpiochip_lock_as_irq(chip, pin);
230 dev_err(chip->parent, "Failed to lock GPIO as interrupt\n");
234 irq = gpiod_to_irq(desc);
236 dev_err(chip->parent, "Failed to translate GPIO to IRQ\n");
237 goto fail_unlock_irq;
240 event = kzalloc(sizeof(*event), GFP_KERNEL);
242 goto fail_unlock_irq;
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;
249 event->irqflags |= IRQF_TRIGGER_LOW;
251 switch (agpio->polarity) {
252 case ACPI_ACTIVE_HIGH:
253 event->irqflags |= IRQF_TRIGGER_RISING;
255 case ACPI_ACTIVE_LOW:
256 event->irqflags |= IRQF_TRIGGER_FALLING;
259 event->irqflags |= IRQF_TRIGGER_RISING |
260 IRQF_TRIGGER_FALLING;
265 event->handle = evt_handle;
266 event->handler = handler;
268 event->irq_is_wake = agpio->wake_capable == ACPI_WAKE_CAPABLE;
272 list_add_tail(&event->node, &acpi_gpio->events);
277 gpiochip_unlock_as_irq(chip, pin);
279 gpiochip_free_own_desc(desc);
285 * acpi_gpiochip_request_interrupts() - Register isr for gpio chip ACPI events
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.
294 void acpi_gpiochip_request_interrupts(struct gpio_chip *chip)
296 struct acpi_gpio_chip *acpi_gpio;
301 if (!chip->parent || !chip->to_irq)
304 handle = ACPI_HANDLE(chip->parent);
308 status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
309 if (ACPI_FAILURE(status))
312 acpi_walk_resources(handle, "_AEI",
313 acpi_gpiochip_alloc_event, acpi_gpio);
315 mutex_lock(&acpi_gpio_deferred_req_irqs_lock);
316 defer = !acpi_gpio_deferred_req_irqs_done;
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);
325 acpi_gpiochip_request_irqs(acpi_gpio);
327 EXPORT_SYMBOL_GPL(acpi_gpiochip_request_interrupts);
330 * acpi_gpiochip_free_interrupts() - Free GPIO ACPI event interrupts.
333 * Free interrupts associated with GPIO ACPI event method for the given
336 void acpi_gpiochip_free_interrupts(struct gpio_chip *chip)
338 struct acpi_gpio_chip *acpi_gpio;
339 struct acpi_gpio_event *event, *ep;
343 if (!chip->parent || !chip->to_irq)
346 handle = ACPI_HANDLE(chip->parent);
350 status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
351 if (ACPI_FAILURE(status))
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);
359 list_for_each_entry_safe_reverse(event, ep, &acpi_gpio->events, node) {
360 struct gpio_desc *desc;
362 if (event->irq_requested) {
363 if (event->irq_is_wake)
364 disable_irq_wake(event->irq);
366 free_irq(event->irq, event);
370 if (WARN_ON(IS_ERR(desc)))
372 gpiochip_unlock_as_irq(chip, event->pin);
373 gpiochip_free_own_desc(desc);
374 list_del(&event->node);
378 EXPORT_SYMBOL_GPL(acpi_gpiochip_free_interrupts);
380 int acpi_dev_add_driver_gpios(struct acpi_device *adev,
381 const struct acpi_gpio_mapping *gpios)
384 adev->driver_gpios = gpios;
389 EXPORT_SYMBOL_GPL(acpi_dev_add_driver_gpios);
391 static void devm_acpi_dev_release_driver_gpios(struct device *dev, void *res)
393 acpi_dev_remove_driver_gpios(ACPI_COMPANION(dev));
396 int devm_acpi_dev_add_driver_gpios(struct device *dev,
397 const struct acpi_gpio_mapping *gpios)
402 res = devres_alloc(devm_acpi_dev_release_driver_gpios, 0, GFP_KERNEL);
406 ret = acpi_dev_add_driver_gpios(ACPI_COMPANION(dev), gpios);
411 devres_add(dev, res);
414 EXPORT_SYMBOL_GPL(devm_acpi_dev_add_driver_gpios);
416 void devm_acpi_dev_remove_driver_gpios(struct device *dev)
418 WARN_ON(devres_release(dev, devm_acpi_dev_release_driver_gpios, NULL, NULL));
420 EXPORT_SYMBOL_GPL(devm_acpi_dev_remove_driver_gpios);
422 static bool acpi_get_driver_gpio_data(struct acpi_device *adev,
423 const char *name, int index,
424 struct fwnode_reference_args *args,
425 unsigned int *quirks)
427 const struct acpi_gpio_mapping *gm;
429 if (!adev->driver_gpios)
432 for (gm = adev->driver_gpios; gm->name; gm++)
433 if (!strcmp(name, gm->name) && gm->data && index < gm->size) {
434 const struct acpi_gpio_params *par = gm->data + index;
436 args->fwnode = acpi_fwnode_handle(adev);
437 args->args[0] = par->crs_entry_index;
438 args->args[1] = par->line_index;
439 args->args[2] = par->active_low;
442 *quirks = gm->quirks;
449 static enum gpiod_flags
450 acpi_gpio_to_gpiod_flags(const struct acpi_resource_gpio *agpio)
452 bool pull_up = agpio->pin_config == ACPI_PIN_CONFIG_PULLUP;
454 switch (agpio->io_restriction) {
455 case ACPI_IO_RESTRICT_INPUT:
457 case ACPI_IO_RESTRICT_OUTPUT:
459 * ACPI GPIO resources don't contain an initial value for the
460 * GPIO. Therefore we deduce that value from the pull field
461 * instead. If the pin is pulled up we assume default to be
462 * high, otherwise low.
464 return pull_up ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW;
467 * Assume that the BIOS has configured the direction and pull
475 __acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags, enum gpiod_flags update)
480 * Check if the BIOS has IoRestriction with explicitly set direction
481 * and update @flags accordingly. Otherwise use whatever caller asked
484 if (update & GPIOD_FLAGS_BIT_DIR_SET) {
485 enum gpiod_flags diff = *flags ^ update;
488 * Check if caller supplied incompatible GPIO initialization
491 * Return %-EINVAL to notify that firmware has different
492 * settings and we are going to use them.
494 if (((*flags & GPIOD_FLAGS_BIT_DIR_SET) && (diff & GPIOD_FLAGS_BIT_DIR_OUT)) ||
495 ((*flags & GPIOD_FLAGS_BIT_DIR_OUT) && (diff & GPIOD_FLAGS_BIT_DIR_VAL)))
503 acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags, struct acpi_gpio_info *info)
505 struct device *dev = &info->adev->dev;
506 enum gpiod_flags old = *flags;
509 ret = __acpi_gpio_update_gpiod_flags(&old, info->flags);
510 if (info->quirks & ACPI_GPIO_QUIRK_NO_IO_RESTRICTION) {
512 dev_warn(dev, FW_BUG "GPIO not in correct mode, fixing\n");
515 dev_dbg(dev, "Override GPIO initialization flags\n");
522 struct acpi_gpio_lookup {
523 struct acpi_gpio_info info;
527 struct gpio_desc *desc;
531 static int acpi_populate_gpio_lookup(struct acpi_resource *ares, void *data)
533 struct acpi_gpio_lookup *lookup = data;
535 if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
538 if (lookup->n++ == lookup->index && !lookup->desc) {
539 const struct acpi_resource_gpio *agpio = &ares->data.gpio;
540 int pin_index = lookup->pin_index;
542 if (pin_index >= agpio->pin_table_length)
545 lookup->desc = acpi_get_gpiod(agpio->resource_source.string_ptr,
546 agpio->pin_table[pin_index]);
547 lookup->info.gpioint =
548 agpio->connection_type == ACPI_RESOURCE_GPIO_TYPE_INT;
551 * Polarity and triggering are only specified for GpioInt
553 * Note: we expect here:
554 * - ACPI_ACTIVE_LOW == GPIO_ACTIVE_LOW
555 * - ACPI_ACTIVE_HIGH == GPIO_ACTIVE_HIGH
557 if (lookup->info.gpioint) {
558 lookup->info.flags = GPIOD_IN;
559 lookup->info.polarity = agpio->polarity;
560 lookup->info.triggering = agpio->triggering;
562 lookup->info.flags = acpi_gpio_to_gpiod_flags(agpio);
563 lookup->info.polarity = lookup->active_low;
570 static int acpi_gpio_resource_lookup(struct acpi_gpio_lookup *lookup,
571 struct acpi_gpio_info *info)
573 struct acpi_device *adev = lookup->info.adev;
574 struct list_head res_list;
577 INIT_LIST_HEAD(&res_list);
579 ret = acpi_dev_get_resources(adev, &res_list,
580 acpi_populate_gpio_lookup,
585 acpi_dev_free_resource_list(&res_list);
591 *info = lookup->info;
595 static int acpi_gpio_property_lookup(struct fwnode_handle *fwnode,
596 const char *propname, int index,
597 struct acpi_gpio_lookup *lookup)
599 struct fwnode_reference_args args;
600 unsigned int quirks = 0;
603 memset(&args, 0, sizeof(args));
604 ret = __acpi_node_get_property_reference(fwnode, propname, index, 3,
607 struct acpi_device *adev = to_acpi_device_node(fwnode);
612 if (!acpi_get_driver_gpio_data(adev, propname, index, &args,
617 * The property was found and resolved, so need to lookup the GPIO based
620 if (!to_acpi_device_node(args.fwnode))
625 lookup->index = args.args[0];
626 lookup->pin_index = args.args[1];
627 lookup->active_low = !!args.args[2];
629 lookup->info.adev = to_acpi_device_node(args.fwnode);
630 lookup->info.quirks = quirks;
636 * acpi_get_gpiod_by_index() - get a GPIO descriptor from device resources
637 * @adev: pointer to a ACPI device to get GPIO from
638 * @propname: Property name of the GPIO (optional)
639 * @index: index of GpioIo/GpioInt resource (starting from %0)
640 * @info: info pointer to fill in (optional)
642 * Function goes through ACPI resources for @adev and based on @index looks
643 * up a GpioIo/GpioInt resource, translates it to the Linux GPIO descriptor,
644 * and returns it. @index matches GpioIo/GpioInt resources only so if there
645 * are total %3 GPIO resources, the index goes from %0 to %2.
647 * If @propname is specified the GPIO is looked using device property. In
648 * that case @index is used to select the GPIO entry in the property value
649 * (in case of multiple).
651 * If the GPIO cannot be translated or there is an error an ERR_PTR is
654 * Note: if the GPIO resource has multiple entries in the pin list, this
655 * function only returns the first.
657 static struct gpio_desc *acpi_get_gpiod_by_index(struct acpi_device *adev,
658 const char *propname, int index,
659 struct acpi_gpio_info *info)
661 struct acpi_gpio_lookup lookup;
665 return ERR_PTR(-ENODEV);
667 memset(&lookup, 0, sizeof(lookup));
668 lookup.index = index;
671 dev_dbg(&adev->dev, "GPIO: looking up %s\n", propname);
673 ret = acpi_gpio_property_lookup(acpi_fwnode_handle(adev),
674 propname, index, &lookup);
678 dev_dbg(&adev->dev, "GPIO: _DSD returned %s %d %d %u\n",
679 dev_name(&lookup.info.adev->dev), lookup.index,
680 lookup.pin_index, lookup.active_low);
682 dev_dbg(&adev->dev, "GPIO: looking up %d in _CRS\n", index);
683 lookup.info.adev = adev;
686 ret = acpi_gpio_resource_lookup(&lookup, info);
687 return ret ? ERR_PTR(ret) : lookup.desc;
690 struct gpio_desc *acpi_find_gpio(struct device *dev,
693 enum gpiod_flags *dflags,
694 enum gpio_lookup_flags *lookupflags)
696 struct acpi_device *adev = ACPI_COMPANION(dev);
697 struct acpi_gpio_info info;
698 struct gpio_desc *desc;
702 /* Try first from _DSD */
703 for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
705 snprintf(propname, sizeof(propname), "%s-%s",
706 con_id, gpio_suffixes[i]);
708 snprintf(propname, sizeof(propname), "%s",
712 desc = acpi_get_gpiod_by_index(adev, propname, idx, &info);
715 if (PTR_ERR(desc) == -EPROBE_DEFER)
716 return ERR_CAST(desc);
719 /* Then from plain _CRS GPIOs */
721 if (!acpi_can_fallback_to_crs(adev, con_id))
722 return ERR_PTR(-ENOENT);
724 desc = acpi_get_gpiod_by_index(adev, NULL, idx, &info);
730 (*dflags == GPIOD_OUT_LOW || *dflags == GPIOD_OUT_HIGH)) {
731 dev_dbg(dev, "refusing GpioInt() entry when doing GPIOD_OUT_* lookup\n");
732 return ERR_PTR(-ENOENT);
735 if (info.polarity == GPIO_ACTIVE_LOW)
736 *lookupflags |= GPIO_ACTIVE_LOW;
738 acpi_gpio_update_gpiod_flags(dflags, &info);
743 * acpi_node_get_gpiod() - get a GPIO descriptor from ACPI resources
744 * @fwnode: pointer to an ACPI firmware node to get the GPIO information from
745 * @propname: Property name of the GPIO
746 * @index: index of GpioIo/GpioInt resource (starting from %0)
747 * @info: info pointer to fill in (optional)
749 * If @fwnode is an ACPI device object, call %acpi_get_gpiod_by_index() for it.
750 * Otherwise (ie. it is a data-only non-device object), use the property-based
751 * GPIO lookup to get to the GPIO resource with the relevant information and use
752 * that to obtain the GPIO descriptor to return.
754 struct gpio_desc *acpi_node_get_gpiod(struct fwnode_handle *fwnode,
755 const char *propname, int index,
756 struct acpi_gpio_info *info)
758 struct acpi_gpio_lookup lookup;
759 struct acpi_device *adev;
762 adev = to_acpi_device_node(fwnode);
764 return acpi_get_gpiod_by_index(adev, propname, index, info);
766 if (!is_acpi_data_node(fwnode))
767 return ERR_PTR(-ENODEV);
770 return ERR_PTR(-EINVAL);
772 memset(&lookup, 0, sizeof(lookup));
773 lookup.index = index;
775 ret = acpi_gpio_property_lookup(fwnode, propname, index, &lookup);
779 ret = acpi_gpio_resource_lookup(&lookup, info);
780 return ret ? ERR_PTR(ret) : lookup.desc;
784 * acpi_dev_gpio_irq_get() - Find GpioInt and translate it to Linux IRQ number
785 * @adev: pointer to a ACPI device to get IRQ from
786 * @index: index of GpioInt resource (starting from %0)
788 * If the device has one or more GpioInt resources, this function can be
789 * used to translate from the GPIO offset in the resource to the Linux IRQ
792 * The function is idempotent, though each time it runs it will configure GPIO
793 * pin direction according to the flags in GpioInt resource.
795 * Return: Linux IRQ number (> %0) on success, negative errno on failure.
797 int acpi_dev_gpio_irq_get(struct acpi_device *adev, int index)
800 unsigned int irq_flags;
803 for (i = 0, idx = 0; idx <= index; i++) {
804 struct acpi_gpio_info info;
805 struct gpio_desc *desc;
807 desc = acpi_get_gpiod_by_index(adev, NULL, i, &info);
809 /* Ignore -EPROBE_DEFER, it only matters if idx matches */
810 if (IS_ERR(desc) && PTR_ERR(desc) != -EPROBE_DEFER)
811 return PTR_ERR(desc);
813 if (info.gpioint && idx++ == index) {
818 return PTR_ERR(desc);
820 irq = gpiod_to_irq(desc);
824 snprintf(label, sizeof(label), "GpioInt() %d", index);
825 ret = gpiod_configure_flags(desc, label, 0, info.flags);
829 irq_flags = acpi_dev_get_irq_type(info.triggering,
832 /* Set type if specified and different than the current one */
833 if (irq_flags != IRQ_TYPE_NONE &&
834 irq_flags != irq_get_trigger_type(irq))
835 irq_set_irq_type(irq, irq_flags);
843 EXPORT_SYMBOL_GPL(acpi_dev_gpio_irq_get);
846 acpi_gpio_adr_space_handler(u32 function, acpi_physical_address address,
847 u32 bits, u64 *value, void *handler_context,
848 void *region_context)
850 struct acpi_gpio_chip *achip = region_context;
851 struct gpio_chip *chip = achip->chip;
852 struct acpi_resource_gpio *agpio;
853 struct acpi_resource *ares;
854 int pin_index = (int)address;
859 status = acpi_buffer_to_resource(achip->conn_info.connection,
860 achip->conn_info.length, &ares);
861 if (ACPI_FAILURE(status))
864 if (WARN_ON(ares->type != ACPI_RESOURCE_TYPE_GPIO)) {
866 return AE_BAD_PARAMETER;
869 agpio = &ares->data.gpio;
871 if (WARN_ON(agpio->io_restriction == ACPI_IO_RESTRICT_INPUT &&
872 function == ACPI_WRITE)) {
874 return AE_BAD_PARAMETER;
877 length = min(agpio->pin_table_length, (u16)(pin_index + bits));
878 for (i = pin_index; i < length; ++i) {
879 int pin = agpio->pin_table[i];
880 struct acpi_gpio_connection *conn;
881 struct gpio_desc *desc;
884 mutex_lock(&achip->conn_lock);
887 list_for_each_entry(conn, &achip->conns, node) {
888 if (conn->pin == pin) {
896 * The same GPIO can be shared between operation region and
897 * event but only if the access here is ACPI_READ. In that
898 * case we "borrow" the event GPIO instead.
900 if (!found && agpio->sharable == ACPI_SHARED &&
901 function == ACPI_READ) {
902 struct acpi_gpio_event *event;
904 list_for_each_entry(event, &achip->events, node) {
905 if (event->pin == pin) {
914 enum gpiod_flags flags = acpi_gpio_to_gpiod_flags(agpio);
915 const char *label = "ACPI:OpRegion";
918 desc = gpiochip_request_own_desc(chip, pin, label);
921 mutex_unlock(&achip->conn_lock);
925 err = gpiod_configure_flags(desc, label, 0, flags);
927 status = AE_NOT_CONFIGURED;
928 gpiochip_free_own_desc(desc);
929 mutex_unlock(&achip->conn_lock);
933 conn = kzalloc(sizeof(*conn), GFP_KERNEL);
935 status = AE_NO_MEMORY;
936 gpiochip_free_own_desc(desc);
937 mutex_unlock(&achip->conn_lock);
943 list_add_tail(&conn->node, &achip->conns);
946 mutex_unlock(&achip->conn_lock);
948 if (function == ACPI_WRITE)
949 gpiod_set_raw_value_cansleep(desc,
950 !!((1 << i) & *value));
952 *value |= (u64)gpiod_get_raw_value_cansleep(desc) << i;
960 static void acpi_gpiochip_request_regions(struct acpi_gpio_chip *achip)
962 struct gpio_chip *chip = achip->chip;
963 acpi_handle handle = ACPI_HANDLE(chip->parent);
966 INIT_LIST_HEAD(&achip->conns);
967 mutex_init(&achip->conn_lock);
968 status = acpi_install_address_space_handler(handle, ACPI_ADR_SPACE_GPIO,
969 acpi_gpio_adr_space_handler,
971 if (ACPI_FAILURE(status))
972 dev_err(chip->parent,
973 "Failed to install GPIO OpRegion handler\n");
976 static void acpi_gpiochip_free_regions(struct acpi_gpio_chip *achip)
978 struct gpio_chip *chip = achip->chip;
979 acpi_handle handle = ACPI_HANDLE(chip->parent);
980 struct acpi_gpio_connection *conn, *tmp;
983 status = acpi_remove_address_space_handler(handle, ACPI_ADR_SPACE_GPIO,
984 acpi_gpio_adr_space_handler);
985 if (ACPI_FAILURE(status)) {
986 dev_err(chip->parent,
987 "Failed to remove GPIO OpRegion handler\n");
991 list_for_each_entry_safe_reverse(conn, tmp, &achip->conns, node) {
992 gpiochip_free_own_desc(conn->desc);
993 list_del(&conn->node);
998 static struct gpio_desc *acpi_gpiochip_parse_own_gpio(
999 struct acpi_gpio_chip *achip, struct fwnode_handle *fwnode,
1000 const char **name, unsigned int *lflags, unsigned int *dflags)
1002 struct gpio_chip *chip = achip->chip;
1003 struct gpio_desc *desc;
1011 ret = fwnode_property_read_u32_array(fwnode, "gpios", gpios,
1014 return ERR_PTR(ret);
1016 desc = gpiochip_get_desc(chip, gpios[0]);
1021 *lflags |= GPIO_ACTIVE_LOW;
1023 if (fwnode_property_present(fwnode, "input"))
1024 *dflags |= GPIOD_IN;
1025 else if (fwnode_property_present(fwnode, "output-low"))
1026 *dflags |= GPIOD_OUT_LOW;
1027 else if (fwnode_property_present(fwnode, "output-high"))
1028 *dflags |= GPIOD_OUT_HIGH;
1030 return ERR_PTR(-EINVAL);
1032 fwnode_property_read_string(fwnode, "line-name", name);
1037 static void acpi_gpiochip_scan_gpios(struct acpi_gpio_chip *achip)
1039 struct gpio_chip *chip = achip->chip;
1040 struct fwnode_handle *fwnode;
1042 device_for_each_child_node(chip->parent, fwnode) {
1043 unsigned int lflags, dflags;
1044 struct gpio_desc *desc;
1048 if (!fwnode_property_present(fwnode, "gpio-hog"))
1051 desc = acpi_gpiochip_parse_own_gpio(achip, fwnode, &name,
1056 ret = gpiod_hog(desc, name, lflags, dflags);
1058 dev_err(chip->parent, "Failed to hog GPIO\n");
1059 fwnode_handle_put(fwnode);
1065 void acpi_gpiochip_add(struct gpio_chip *chip)
1067 struct acpi_gpio_chip *acpi_gpio;
1071 if (!chip || !chip->parent)
1074 handle = ACPI_HANDLE(chip->parent);
1078 acpi_gpio = kzalloc(sizeof(*acpi_gpio), GFP_KERNEL);
1080 dev_err(chip->parent,
1081 "Failed to allocate memory for ACPI GPIO chip\n");
1085 acpi_gpio->chip = chip;
1086 INIT_LIST_HEAD(&acpi_gpio->events);
1087 INIT_LIST_HEAD(&acpi_gpio->deferred_req_irqs_list_entry);
1089 status = acpi_attach_data(handle, acpi_gpio_chip_dh, acpi_gpio);
1090 if (ACPI_FAILURE(status)) {
1091 dev_err(chip->parent, "Failed to attach ACPI GPIO chip\n");
1097 devprop_gpiochip_set_names(chip, dev_fwnode(chip->parent));
1099 acpi_gpiochip_request_regions(acpi_gpio);
1100 acpi_gpiochip_scan_gpios(acpi_gpio);
1101 acpi_walk_dep_device_list(handle);
1104 void acpi_gpiochip_remove(struct gpio_chip *chip)
1106 struct acpi_gpio_chip *acpi_gpio;
1110 if (!chip || !chip->parent)
1113 handle = ACPI_HANDLE(chip->parent);
1117 status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
1118 if (ACPI_FAILURE(status)) {
1119 dev_warn(chip->parent, "Failed to retrieve ACPI GPIO chip\n");
1123 acpi_gpiochip_free_regions(acpi_gpio);
1125 acpi_detach_data(handle, acpi_gpio_chip_dh);
1129 static int acpi_gpio_package_count(const union acpi_object *obj)
1131 const union acpi_object *element = obj->package.elements;
1132 const union acpi_object *end = element + obj->package.count;
1133 unsigned int count = 0;
1135 while (element < end) {
1136 switch (element->type) {
1137 case ACPI_TYPE_LOCAL_REFERENCE:
1140 case ACPI_TYPE_INTEGER:
1153 static int acpi_find_gpio_count(struct acpi_resource *ares, void *data)
1155 unsigned int *count = data;
1157 if (ares->type == ACPI_RESOURCE_TYPE_GPIO)
1158 *count += ares->data.gpio.pin_table_length;
1164 * acpi_gpio_count - return the number of GPIOs associated with a
1165 * device / function or -ENOENT if no GPIO has been
1166 * assigned to the requested function.
1167 * @dev: GPIO consumer, can be NULL for system-global GPIOs
1168 * @con_id: function within the GPIO consumer
1170 int acpi_gpio_count(struct device *dev, const char *con_id)
1172 struct acpi_device *adev = ACPI_COMPANION(dev);
1173 const union acpi_object *obj;
1174 const struct acpi_gpio_mapping *gm;
1175 int count = -ENOENT;
1180 /* Try first from _DSD */
1181 for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
1183 snprintf(propname, sizeof(propname), "%s-%s",
1184 con_id, gpio_suffixes[i]);
1186 snprintf(propname, sizeof(propname), "%s",
1189 ret = acpi_dev_get_property(adev, propname, ACPI_TYPE_ANY,
1192 if (obj->type == ACPI_TYPE_LOCAL_REFERENCE)
1194 else if (obj->type == ACPI_TYPE_PACKAGE)
1195 count = acpi_gpio_package_count(obj);
1196 } else if (adev->driver_gpios) {
1197 for (gm = adev->driver_gpios; gm->name; gm++)
1198 if (strcmp(propname, gm->name) == 0) {
1207 /* Then from plain _CRS GPIOs */
1209 struct list_head resource_list;
1210 unsigned int crs_count = 0;
1212 if (!acpi_can_fallback_to_crs(adev, con_id))
1215 INIT_LIST_HEAD(&resource_list);
1216 acpi_dev_get_resources(adev, &resource_list,
1217 acpi_find_gpio_count, &crs_count);
1218 acpi_dev_free_resource_list(&resource_list);
1222 return count ? count : -ENOENT;
1225 bool acpi_can_fallback_to_crs(struct acpi_device *adev, const char *con_id)
1227 /* Never allow fallback if the device has properties */
1228 if (acpi_dev_has_props(adev) || adev->driver_gpios)
1231 return con_id == NULL;
1234 /* Run deferred acpi_gpiochip_request_irqs() */
1235 static int acpi_gpio_handle_deferred_request_irqs(void)
1237 struct acpi_gpio_chip *acpi_gpio, *tmp;
1239 mutex_lock(&acpi_gpio_deferred_req_irqs_lock);
1240 list_for_each_entry_safe(acpi_gpio, tmp,
1241 &acpi_gpio_deferred_req_irqs_list,
1242 deferred_req_irqs_list_entry)
1243 acpi_gpiochip_request_irqs(acpi_gpio);
1245 acpi_gpio_deferred_req_irqs_done = true;
1246 mutex_unlock(&acpi_gpio_deferred_req_irqs_lock);
1250 /* We must use _sync so that this runs after the first deferred_probe run */
1251 late_initcall_sync(acpi_gpio_handle_deferred_request_irqs);