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", 0);
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 if (event->irq_requested) {
361 if (event->irq_is_wake)
362 disable_irq_wake(event->irq);
364 free_irq(event->irq, event);
367 gpiochip_unlock_as_irq(chip, event->pin);
368 gpiochip_free_own_desc(event->desc);
369 list_del(&event->node);
373 EXPORT_SYMBOL_GPL(acpi_gpiochip_free_interrupts);
375 int acpi_dev_add_driver_gpios(struct acpi_device *adev,
376 const struct acpi_gpio_mapping *gpios)
379 adev->driver_gpios = gpios;
384 EXPORT_SYMBOL_GPL(acpi_dev_add_driver_gpios);
386 static void devm_acpi_dev_release_driver_gpios(struct device *dev, void *res)
388 acpi_dev_remove_driver_gpios(ACPI_COMPANION(dev));
391 int devm_acpi_dev_add_driver_gpios(struct device *dev,
392 const struct acpi_gpio_mapping *gpios)
397 res = devres_alloc(devm_acpi_dev_release_driver_gpios, 0, GFP_KERNEL);
401 ret = acpi_dev_add_driver_gpios(ACPI_COMPANION(dev), gpios);
406 devres_add(dev, res);
409 EXPORT_SYMBOL_GPL(devm_acpi_dev_add_driver_gpios);
411 void devm_acpi_dev_remove_driver_gpios(struct device *dev)
413 WARN_ON(devres_release(dev, devm_acpi_dev_release_driver_gpios, NULL, NULL));
415 EXPORT_SYMBOL_GPL(devm_acpi_dev_remove_driver_gpios);
417 static 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)
422 const struct acpi_gpio_mapping *gm;
424 if (!adev->driver_gpios)
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;
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;
437 *quirks = gm->quirks;
444 static enum gpiod_flags
445 acpi_gpio_to_gpiod_flags(const struct acpi_resource_gpio *agpio)
447 bool pull_up = agpio->pin_config == ACPI_PIN_CONFIG_PULLUP;
449 switch (agpio->io_restriction) {
450 case ACPI_IO_RESTRICT_INPUT:
452 case ACPI_IO_RESTRICT_OUTPUT:
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.
459 return pull_up ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW;
462 * Assume that the BIOS has configured the direction and pull
470 __acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags, enum gpiod_flags update)
475 * Check if the BIOS has IoRestriction with explicitly set direction
476 * and update @flags accordingly. Otherwise use whatever caller asked
479 if (update & GPIOD_FLAGS_BIT_DIR_SET) {
480 enum gpiod_flags diff = *flags ^ update;
483 * Check if caller supplied incompatible GPIO initialization
486 * Return %-EINVAL to notify that firmware has different
487 * settings and we are going to use them.
489 if (((*flags & GPIOD_FLAGS_BIT_DIR_SET) && (diff & GPIOD_FLAGS_BIT_DIR_OUT)) ||
490 ((*flags & GPIOD_FLAGS_BIT_DIR_OUT) && (diff & GPIOD_FLAGS_BIT_DIR_VAL)))
498 acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags, struct acpi_gpio_info *info)
500 struct device *dev = &info->adev->dev;
501 enum gpiod_flags old = *flags;
504 ret = __acpi_gpio_update_gpiod_flags(&old, info->flags);
505 if (info->quirks & ACPI_GPIO_QUIRK_NO_IO_RESTRICTION) {
507 dev_warn(dev, FW_BUG "GPIO not in correct mode, fixing\n");
510 dev_dbg(dev, "Override GPIO initialization flags\n");
517 struct acpi_gpio_lookup {
518 struct acpi_gpio_info info;
522 struct gpio_desc *desc;
526 static int acpi_populate_gpio_lookup(struct acpi_resource *ares, void *data)
528 struct acpi_gpio_lookup *lookup = data;
530 if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
533 if (lookup->n++ == lookup->index && !lookup->desc) {
534 const struct acpi_resource_gpio *agpio = &ares->data.gpio;
535 int pin_index = lookup->pin_index;
537 if (pin_index >= agpio->pin_table_length)
540 lookup->desc = acpi_get_gpiod(agpio->resource_source.string_ptr,
541 agpio->pin_table[pin_index]);
542 lookup->info.gpioint =
543 agpio->connection_type == ACPI_RESOURCE_GPIO_TYPE_INT;
546 * Polarity and triggering are only specified for GpioInt
548 * Note: we expect here:
549 * - ACPI_ACTIVE_LOW == GPIO_ACTIVE_LOW
550 * - ACPI_ACTIVE_HIGH == GPIO_ACTIVE_HIGH
552 if (lookup->info.gpioint) {
553 lookup->info.flags = GPIOD_IN;
554 lookup->info.polarity = agpio->polarity;
555 lookup->info.triggering = agpio->triggering;
557 lookup->info.flags = acpi_gpio_to_gpiod_flags(agpio);
558 lookup->info.polarity = lookup->active_low;
565 static int acpi_gpio_resource_lookup(struct acpi_gpio_lookup *lookup,
566 struct acpi_gpio_info *info)
568 struct acpi_device *adev = lookup->info.adev;
569 struct list_head res_list;
572 INIT_LIST_HEAD(&res_list);
574 ret = acpi_dev_get_resources(adev, &res_list,
575 acpi_populate_gpio_lookup,
580 acpi_dev_free_resource_list(&res_list);
586 *info = lookup->info;
590 static int acpi_gpio_property_lookup(struct fwnode_handle *fwnode,
591 const char *propname, int index,
592 struct acpi_gpio_lookup *lookup)
594 struct fwnode_reference_args args;
595 unsigned int quirks = 0;
598 memset(&args, 0, sizeof(args));
599 ret = __acpi_node_get_property_reference(fwnode, propname, index, 3,
602 struct acpi_device *adev = to_acpi_device_node(fwnode);
607 if (!acpi_get_driver_gpio_data(adev, propname, index, &args,
612 * The property was found and resolved, so need to lookup the GPIO based
615 if (!to_acpi_device_node(args.fwnode))
620 lookup->index = args.args[0];
621 lookup->pin_index = args.args[1];
622 lookup->active_low = !!args.args[2];
624 lookup->info.adev = to_acpi_device_node(args.fwnode);
625 lookup->info.quirks = quirks;
631 * acpi_get_gpiod_by_index() - get a GPIO descriptor from device resources
632 * @adev: pointer to a ACPI device to get GPIO from
633 * @propname: Property name of the GPIO (optional)
634 * @index: index of GpioIo/GpioInt resource (starting from %0)
635 * @info: info pointer to fill in (optional)
637 * Function goes through ACPI resources for @adev and based on @index looks
638 * up a GpioIo/GpioInt resource, translates it to the Linux GPIO descriptor,
639 * and returns it. @index matches GpioIo/GpioInt resources only so if there
640 * are total %3 GPIO resources, the index goes from %0 to %2.
642 * If @propname is specified the GPIO is looked using device property. In
643 * that case @index is used to select the GPIO entry in the property value
644 * (in case of multiple).
646 * If the GPIO cannot be translated or there is an error an ERR_PTR is
649 * Note: if the GPIO resource has multiple entries in the pin list, this
650 * function only returns the first.
652 static struct gpio_desc *acpi_get_gpiod_by_index(struct acpi_device *adev,
653 const char *propname, int index,
654 struct acpi_gpio_info *info)
656 struct acpi_gpio_lookup lookup;
660 return ERR_PTR(-ENODEV);
662 memset(&lookup, 0, sizeof(lookup));
663 lookup.index = index;
666 dev_dbg(&adev->dev, "GPIO: looking up %s\n", propname);
668 ret = acpi_gpio_property_lookup(acpi_fwnode_handle(adev),
669 propname, index, &lookup);
673 dev_dbg(&adev->dev, "GPIO: _DSD returned %s %d %d %u\n",
674 dev_name(&lookup.info.adev->dev), lookup.index,
675 lookup.pin_index, lookup.active_low);
677 dev_dbg(&adev->dev, "GPIO: looking up %d in _CRS\n", index);
678 lookup.info.adev = adev;
681 ret = acpi_gpio_resource_lookup(&lookup, info);
682 return ret ? ERR_PTR(ret) : lookup.desc;
685 struct gpio_desc *acpi_find_gpio(struct device *dev,
688 enum gpiod_flags *dflags,
689 enum gpio_lookup_flags *lookupflags)
691 struct acpi_device *adev = ACPI_COMPANION(dev);
692 struct acpi_gpio_info info;
693 struct gpio_desc *desc;
697 /* Try first from _DSD */
698 for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
700 snprintf(propname, sizeof(propname), "%s-%s",
701 con_id, gpio_suffixes[i]);
703 snprintf(propname, sizeof(propname), "%s",
707 desc = acpi_get_gpiod_by_index(adev, propname, idx, &info);
710 if (PTR_ERR(desc) == -EPROBE_DEFER)
711 return ERR_CAST(desc);
714 /* Then from plain _CRS GPIOs */
716 if (!acpi_can_fallback_to_crs(adev, con_id))
717 return ERR_PTR(-ENOENT);
719 desc = acpi_get_gpiod_by_index(adev, NULL, idx, &info);
725 (*dflags == GPIOD_OUT_LOW || *dflags == GPIOD_OUT_HIGH)) {
726 dev_dbg(dev, "refusing GpioInt() entry when doing GPIOD_OUT_* lookup\n");
727 return ERR_PTR(-ENOENT);
730 if (info.polarity == GPIO_ACTIVE_LOW)
731 *lookupflags |= GPIO_ACTIVE_LOW;
733 acpi_gpio_update_gpiod_flags(dflags, &info);
738 * acpi_node_get_gpiod() - get a GPIO descriptor from ACPI resources
739 * @fwnode: pointer to an ACPI firmware node to get the GPIO information from
740 * @propname: Property name of the GPIO
741 * @index: index of GpioIo/GpioInt resource (starting from %0)
742 * @info: info pointer to fill in (optional)
744 * If @fwnode is an ACPI device object, call %acpi_get_gpiod_by_index() for it.
745 * Otherwise (ie. it is a data-only non-device object), use the property-based
746 * GPIO lookup to get to the GPIO resource with the relevant information and use
747 * that to obtain the GPIO descriptor to return.
749 struct gpio_desc *acpi_node_get_gpiod(struct fwnode_handle *fwnode,
750 const char *propname, int index,
751 struct acpi_gpio_info *info)
753 struct acpi_gpio_lookup lookup;
754 struct acpi_device *adev;
757 adev = to_acpi_device_node(fwnode);
759 return acpi_get_gpiod_by_index(adev, propname, index, info);
761 if (!is_acpi_data_node(fwnode))
762 return ERR_PTR(-ENODEV);
765 return ERR_PTR(-EINVAL);
767 memset(&lookup, 0, sizeof(lookup));
768 lookup.index = index;
770 ret = acpi_gpio_property_lookup(fwnode, propname, index, &lookup);
774 ret = acpi_gpio_resource_lookup(&lookup, info);
775 return ret ? ERR_PTR(ret) : lookup.desc;
779 * acpi_dev_gpio_irq_get() - Find GpioInt and translate it to Linux IRQ number
780 * @adev: pointer to a ACPI device to get IRQ from
781 * @index: index of GpioInt resource (starting from %0)
783 * If the device has one or more GpioInt resources, this function can be
784 * used to translate from the GPIO offset in the resource to the Linux IRQ
787 * The function is idempotent, though each time it runs it will configure GPIO
788 * pin direction according to the flags in GpioInt resource.
790 * Return: Linux IRQ number (> %0) on success, negative errno on failure.
792 int acpi_dev_gpio_irq_get(struct acpi_device *adev, int index)
795 unsigned int irq_flags;
798 for (i = 0, idx = 0; idx <= index; i++) {
799 struct acpi_gpio_info info;
800 struct gpio_desc *desc;
802 desc = acpi_get_gpiod_by_index(adev, NULL, i, &info);
804 /* Ignore -EPROBE_DEFER, it only matters if idx matches */
805 if (IS_ERR(desc) && PTR_ERR(desc) != -EPROBE_DEFER)
806 return PTR_ERR(desc);
808 if (info.gpioint && idx++ == index) {
813 return PTR_ERR(desc);
815 irq = gpiod_to_irq(desc);
819 snprintf(label, sizeof(label), "GpioInt() %d", index);
820 ret = gpiod_configure_flags(desc, label, 0, info.flags);
824 irq_flags = acpi_dev_get_irq_type(info.triggering,
827 /* Set type if specified and different than the current one */
828 if (irq_flags != IRQ_TYPE_NONE &&
829 irq_flags != irq_get_trigger_type(irq))
830 irq_set_irq_type(irq, irq_flags);
838 EXPORT_SYMBOL_GPL(acpi_dev_gpio_irq_get);
841 acpi_gpio_adr_space_handler(u32 function, acpi_physical_address address,
842 u32 bits, u64 *value, void *handler_context,
843 void *region_context)
845 struct acpi_gpio_chip *achip = region_context;
846 struct gpio_chip *chip = achip->chip;
847 struct acpi_resource_gpio *agpio;
848 struct acpi_resource *ares;
849 int pin_index = (int)address;
854 status = acpi_buffer_to_resource(achip->conn_info.connection,
855 achip->conn_info.length, &ares);
856 if (ACPI_FAILURE(status))
859 if (WARN_ON(ares->type != ACPI_RESOURCE_TYPE_GPIO)) {
861 return AE_BAD_PARAMETER;
864 agpio = &ares->data.gpio;
866 if (WARN_ON(agpio->io_restriction == ACPI_IO_RESTRICT_INPUT &&
867 function == ACPI_WRITE)) {
869 return AE_BAD_PARAMETER;
872 length = min(agpio->pin_table_length, (u16)(pin_index + bits));
873 for (i = pin_index; i < length; ++i) {
874 int pin = agpio->pin_table[i];
875 struct acpi_gpio_connection *conn;
876 struct gpio_desc *desc;
879 mutex_lock(&achip->conn_lock);
882 list_for_each_entry(conn, &achip->conns, node) {
883 if (conn->pin == pin) {
891 * The same GPIO can be shared between operation region and
892 * event but only if the access here is ACPI_READ. In that
893 * case we "borrow" the event GPIO instead.
895 if (!found && agpio->sharable == ACPI_SHARED &&
896 function == ACPI_READ) {
897 struct acpi_gpio_event *event;
899 list_for_each_entry(event, &achip->events, node) {
900 if (event->pin == pin) {
909 enum gpiod_flags flags = acpi_gpio_to_gpiod_flags(agpio);
910 const char *label = "ACPI:OpRegion";
912 desc = gpiochip_request_own_desc(chip, pin, label,
916 mutex_unlock(&achip->conn_lock);
920 conn = kzalloc(sizeof(*conn), GFP_KERNEL);
922 status = AE_NO_MEMORY;
923 gpiochip_free_own_desc(desc);
924 mutex_unlock(&achip->conn_lock);
930 list_add_tail(&conn->node, &achip->conns);
933 mutex_unlock(&achip->conn_lock);
935 if (function == ACPI_WRITE)
936 gpiod_set_raw_value_cansleep(desc,
937 !!((1 << i) & *value));
939 *value |= (u64)gpiod_get_raw_value_cansleep(desc) << i;
947 static void acpi_gpiochip_request_regions(struct acpi_gpio_chip *achip)
949 struct gpio_chip *chip = achip->chip;
950 acpi_handle handle = ACPI_HANDLE(chip->parent);
953 INIT_LIST_HEAD(&achip->conns);
954 mutex_init(&achip->conn_lock);
955 status = acpi_install_address_space_handler(handle, ACPI_ADR_SPACE_GPIO,
956 acpi_gpio_adr_space_handler,
958 if (ACPI_FAILURE(status))
959 dev_err(chip->parent,
960 "Failed to install GPIO OpRegion handler\n");
963 static void acpi_gpiochip_free_regions(struct acpi_gpio_chip *achip)
965 struct gpio_chip *chip = achip->chip;
966 acpi_handle handle = ACPI_HANDLE(chip->parent);
967 struct acpi_gpio_connection *conn, *tmp;
970 status = acpi_remove_address_space_handler(handle, ACPI_ADR_SPACE_GPIO,
971 acpi_gpio_adr_space_handler);
972 if (ACPI_FAILURE(status)) {
973 dev_err(chip->parent,
974 "Failed to remove GPIO OpRegion handler\n");
978 list_for_each_entry_safe_reverse(conn, tmp, &achip->conns, node) {
979 gpiochip_free_own_desc(conn->desc);
980 list_del(&conn->node);
985 static struct gpio_desc *acpi_gpiochip_parse_own_gpio(
986 struct acpi_gpio_chip *achip, struct fwnode_handle *fwnode,
987 const char **name, unsigned int *lflags, unsigned int *dflags)
989 struct gpio_chip *chip = achip->chip;
990 struct gpio_desc *desc;
998 ret = fwnode_property_read_u32_array(fwnode, "gpios", gpios,
1001 return ERR_PTR(ret);
1003 desc = gpiochip_get_desc(chip, gpios[0]);
1008 *lflags |= GPIO_ACTIVE_LOW;
1010 if (fwnode_property_present(fwnode, "input"))
1011 *dflags |= GPIOD_IN;
1012 else if (fwnode_property_present(fwnode, "output-low"))
1013 *dflags |= GPIOD_OUT_LOW;
1014 else if (fwnode_property_present(fwnode, "output-high"))
1015 *dflags |= GPIOD_OUT_HIGH;
1017 return ERR_PTR(-EINVAL);
1019 fwnode_property_read_string(fwnode, "line-name", name);
1024 static void acpi_gpiochip_scan_gpios(struct acpi_gpio_chip *achip)
1026 struct gpio_chip *chip = achip->chip;
1027 struct fwnode_handle *fwnode;
1029 device_for_each_child_node(chip->parent, fwnode) {
1030 unsigned int lflags, dflags;
1031 struct gpio_desc *desc;
1035 if (!fwnode_property_present(fwnode, "gpio-hog"))
1038 desc = acpi_gpiochip_parse_own_gpio(achip, fwnode, &name,
1043 ret = gpiod_hog(desc, name, lflags, dflags);
1045 dev_err(chip->parent, "Failed to hog GPIO\n");
1046 fwnode_handle_put(fwnode);
1052 void acpi_gpiochip_add(struct gpio_chip *chip)
1054 struct acpi_gpio_chip *acpi_gpio;
1058 if (!chip || !chip->parent)
1061 handle = ACPI_HANDLE(chip->parent);
1065 acpi_gpio = kzalloc(sizeof(*acpi_gpio), GFP_KERNEL);
1067 dev_err(chip->parent,
1068 "Failed to allocate memory for ACPI GPIO chip\n");
1072 acpi_gpio->chip = chip;
1073 INIT_LIST_HEAD(&acpi_gpio->events);
1074 INIT_LIST_HEAD(&acpi_gpio->deferred_req_irqs_list_entry);
1076 status = acpi_attach_data(handle, acpi_gpio_chip_dh, acpi_gpio);
1077 if (ACPI_FAILURE(status)) {
1078 dev_err(chip->parent, "Failed to attach ACPI GPIO chip\n");
1084 devprop_gpiochip_set_names(chip, dev_fwnode(chip->parent));
1086 acpi_gpiochip_request_regions(acpi_gpio);
1087 acpi_gpiochip_scan_gpios(acpi_gpio);
1088 acpi_walk_dep_device_list(handle);
1091 void acpi_gpiochip_remove(struct gpio_chip *chip)
1093 struct acpi_gpio_chip *acpi_gpio;
1097 if (!chip || !chip->parent)
1100 handle = ACPI_HANDLE(chip->parent);
1104 status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
1105 if (ACPI_FAILURE(status)) {
1106 dev_warn(chip->parent, "Failed to retrieve ACPI GPIO chip\n");
1110 acpi_gpiochip_free_regions(acpi_gpio);
1112 acpi_detach_data(handle, acpi_gpio_chip_dh);
1116 static int acpi_gpio_package_count(const union acpi_object *obj)
1118 const union acpi_object *element = obj->package.elements;
1119 const union acpi_object *end = element + obj->package.count;
1120 unsigned int count = 0;
1122 while (element < end) {
1123 switch (element->type) {
1124 case ACPI_TYPE_LOCAL_REFERENCE:
1127 case ACPI_TYPE_INTEGER:
1140 static int acpi_find_gpio_count(struct acpi_resource *ares, void *data)
1142 unsigned int *count = data;
1144 if (ares->type == ACPI_RESOURCE_TYPE_GPIO)
1145 *count += ares->data.gpio.pin_table_length;
1151 * acpi_gpio_count - return the number of GPIOs associated with a
1152 * device / function or -ENOENT if no GPIO has been
1153 * assigned to the requested function.
1154 * @dev: GPIO consumer, can be NULL for system-global GPIOs
1155 * @con_id: function within the GPIO consumer
1157 int acpi_gpio_count(struct device *dev, const char *con_id)
1159 struct acpi_device *adev = ACPI_COMPANION(dev);
1160 const union acpi_object *obj;
1161 const struct acpi_gpio_mapping *gm;
1162 int count = -ENOENT;
1167 /* Try first from _DSD */
1168 for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
1170 snprintf(propname, sizeof(propname), "%s-%s",
1171 con_id, gpio_suffixes[i]);
1173 snprintf(propname, sizeof(propname), "%s",
1176 ret = acpi_dev_get_property(adev, propname, ACPI_TYPE_ANY,
1179 if (obj->type == ACPI_TYPE_LOCAL_REFERENCE)
1181 else if (obj->type == ACPI_TYPE_PACKAGE)
1182 count = acpi_gpio_package_count(obj);
1183 } else if (adev->driver_gpios) {
1184 for (gm = adev->driver_gpios; gm->name; gm++)
1185 if (strcmp(propname, gm->name) == 0) {
1194 /* Then from plain _CRS GPIOs */
1196 struct list_head resource_list;
1197 unsigned int crs_count = 0;
1199 if (!acpi_can_fallback_to_crs(adev, con_id))
1202 INIT_LIST_HEAD(&resource_list);
1203 acpi_dev_get_resources(adev, &resource_list,
1204 acpi_find_gpio_count, &crs_count);
1205 acpi_dev_free_resource_list(&resource_list);
1209 return count ? count : -ENOENT;
1212 bool acpi_can_fallback_to_crs(struct acpi_device *adev, const char *con_id)
1214 /* Never allow fallback if the device has properties */
1215 if (acpi_dev_has_props(adev) || adev->driver_gpios)
1218 return con_id == NULL;
1221 /* Run deferred acpi_gpiochip_request_irqs() */
1222 static int acpi_gpio_handle_deferred_request_irqs(void)
1224 struct acpi_gpio_chip *acpi_gpio, *tmp;
1226 mutex_lock(&acpi_gpio_deferred_req_irqs_lock);
1227 list_for_each_entry_safe(acpi_gpio, tmp,
1228 &acpi_gpio_deferred_req_irqs_list,
1229 deferred_req_irqs_list_entry)
1230 acpi_gpiochip_request_irqs(acpi_gpio);
1232 acpi_gpio_deferred_req_irqs_done = true;
1233 mutex_unlock(&acpi_gpio_deferred_req_irqs_lock);
1237 /* We must use _sync so that this runs after the first deferred_probe run */
1238 late_initcall_sync(acpi_gpio_handle_deferred_request_irqs);