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>
22 struct acpi_gpio_event {
23 struct list_head node;
27 struct gpio_desc *desc;
30 struct acpi_gpio_connection {
31 struct list_head node;
33 struct gpio_desc *desc;
36 struct acpi_gpio_chip {
38 * ACPICA requires that the first field of the context parameter
39 * passed to acpi_install_address_space_handler() is large enough
40 * to hold struct acpi_connection_info.
42 struct acpi_connection_info conn_info;
43 struct list_head conns;
44 struct mutex conn_lock;
45 struct gpio_chip *chip;
46 struct list_head events;
47 struct list_head deferred_req_irqs_list_entry;
51 * For gpiochips which call acpi_gpiochip_request_interrupts() before late_init
52 * (so builtin drivers) we register the ACPI GpioInt event handlers from a
53 * late_initcall_sync handler, so that other builtin drivers can register their
54 * OpRegions before the event handlers can run. This list contains gpiochips
55 * for which the acpi_gpiochip_request_interrupts() has been deferred.
57 static DEFINE_MUTEX(acpi_gpio_deferred_req_irqs_lock);
58 static LIST_HEAD(acpi_gpio_deferred_req_irqs_list);
59 static bool acpi_gpio_deferred_req_irqs_done;
61 static int acpi_gpiochip_find(struct gpio_chip *gc, void *data)
66 return ACPI_HANDLE(gc->parent) == data;
70 * acpi_get_gpiod() - Translate ACPI GPIO pin to GPIO descriptor usable with GPIO API
71 * @path: ACPI GPIO controller full path name, (e.g. "\\_SB.GPO1")
72 * @pin: ACPI GPIO pin number (0-based, controller-relative)
74 * Return: GPIO descriptor to use with Linux generic GPIO API, or ERR_PTR
75 * error value. Specifically returns %-EPROBE_DEFER if the referenced GPIO
76 * controller does not have gpiochip registered at the moment. This is to
77 * support probe deferral.
79 static struct gpio_desc *acpi_get_gpiod(char *path, int pin)
81 struct gpio_chip *chip;
85 status = acpi_get_handle(NULL, path, &handle);
86 if (ACPI_FAILURE(status))
87 return ERR_PTR(-ENODEV);
89 chip = gpiochip_find(handle, acpi_gpiochip_find);
91 return ERR_PTR(-EPROBE_DEFER);
93 return gpiochip_get_desc(chip, pin);
96 static irqreturn_t acpi_gpio_irq_handler(int irq, void *data)
98 struct acpi_gpio_event *event = data;
100 acpi_evaluate_object(event->handle, NULL, NULL, NULL);
105 static irqreturn_t acpi_gpio_irq_handler_evt(int irq, void *data)
107 struct acpi_gpio_event *event = data;
109 acpi_execute_simple_method(event->handle, NULL, event->pin);
114 static void acpi_gpio_chip_dh(acpi_handle handle, void *data)
116 /* The address of this function is used as a key. */
119 bool acpi_gpio_get_irq_resource(struct acpi_resource *ares,
120 struct acpi_resource_gpio **agpio)
122 struct acpi_resource_gpio *gpio;
124 if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
127 gpio = &ares->data.gpio;
128 if (gpio->connection_type != ACPI_RESOURCE_GPIO_TYPE_INT)
134 EXPORT_SYMBOL_GPL(acpi_gpio_get_irq_resource);
136 static acpi_status acpi_gpiochip_request_interrupt(struct acpi_resource *ares,
139 struct acpi_gpio_chip *acpi_gpio = context;
140 struct gpio_chip *chip = acpi_gpio->chip;
141 struct acpi_resource_gpio *agpio;
142 acpi_handle handle, evt_handle;
143 struct acpi_gpio_event *event;
144 irq_handler_t handler = NULL;
145 struct gpio_desc *desc;
146 unsigned long irqflags;
147 int ret, pin, irq, value;
149 if (!acpi_gpio_get_irq_resource(ares, &agpio))
152 handle = ACPI_HANDLE(chip->parent);
153 pin = agpio->pin_table[0];
157 sprintf(ev_name, "_%c%02hhX",
158 agpio->triggering == ACPI_EDGE_SENSITIVE ? 'E' : 'L',
160 if (ACPI_SUCCESS(acpi_get_handle(handle, ev_name, &evt_handle)))
161 handler = acpi_gpio_irq_handler;
164 if (ACPI_SUCCESS(acpi_get_handle(handle, "_EVT", &evt_handle)))
165 handler = acpi_gpio_irq_handler_evt;
170 desc = gpiochip_request_own_desc(chip, pin, "ACPI:Event");
172 dev_err(chip->parent, "Failed to request GPIO\n");
176 gpiod_direction_input(desc);
178 value = gpiod_get_value_cansleep(desc);
180 ret = gpiochip_lock_as_irq(chip, pin);
182 dev_err(chip->parent, "Failed to lock GPIO as interrupt\n");
186 irq = gpiod_to_irq(desc);
188 dev_err(chip->parent, "Failed to translate GPIO to IRQ\n");
189 goto fail_unlock_irq;
192 irqflags = IRQF_ONESHOT;
193 if (agpio->triggering == ACPI_LEVEL_SENSITIVE) {
194 if (agpio->polarity == ACPI_ACTIVE_HIGH)
195 irqflags |= IRQF_TRIGGER_HIGH;
197 irqflags |= IRQF_TRIGGER_LOW;
199 switch (agpio->polarity) {
200 case ACPI_ACTIVE_HIGH:
201 irqflags |= IRQF_TRIGGER_RISING;
203 case ACPI_ACTIVE_LOW:
204 irqflags |= IRQF_TRIGGER_FALLING;
207 irqflags |= IRQF_TRIGGER_RISING |
208 IRQF_TRIGGER_FALLING;
213 event = kzalloc(sizeof(*event), GFP_KERNEL);
215 goto fail_unlock_irq;
217 event->handle = evt_handle;
222 ret = request_threaded_irq(event->irq, NULL, handler, irqflags,
223 "ACPI:Event", event);
225 dev_err(chip->parent,
226 "Failed to setup interrupt handler for %d\n",
228 goto fail_free_event;
231 if (agpio->wake_capable == ACPI_WAKE_CAPABLE)
232 enable_irq_wake(irq);
234 list_add_tail(&event->node, &acpi_gpio->events);
237 * Make sure we trigger the initial state of the IRQ when using RISING
238 * or FALLING. Note we run the handlers on late_init, the AML code
239 * may refer to OperationRegions from other (builtin) drivers which
240 * may be probed after us.
242 if (((irqflags & IRQF_TRIGGER_RISING) && value == 1) ||
243 ((irqflags & IRQF_TRIGGER_FALLING) && value == 0))
244 handler(event->irq, event);
251 gpiochip_unlock_as_irq(chip, pin);
253 gpiochip_free_own_desc(desc);
259 * acpi_gpiochip_request_interrupts() - Register isr for gpio chip ACPI events
262 * ACPI5 platforms can use GPIO signaled ACPI events. These GPIO interrupts are
263 * handled by ACPI event methods which need to be called from the GPIO
264 * chip's interrupt handler. acpi_gpiochip_request_interrupts finds out which
265 * gpio pins have acpi event methods and assigns interrupt handlers that calls
266 * the acpi event methods for those pins.
268 void acpi_gpiochip_request_interrupts(struct gpio_chip *chip)
270 struct acpi_gpio_chip *acpi_gpio;
275 if (!chip->parent || !chip->to_irq)
278 handle = ACPI_HANDLE(chip->parent);
282 status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
283 if (ACPI_FAILURE(status))
286 mutex_lock(&acpi_gpio_deferred_req_irqs_lock);
287 defer = !acpi_gpio_deferred_req_irqs_done;
289 list_add(&acpi_gpio->deferred_req_irqs_list_entry,
290 &acpi_gpio_deferred_req_irqs_list);
291 mutex_unlock(&acpi_gpio_deferred_req_irqs_lock);
296 acpi_walk_resources(handle, "_AEI",
297 acpi_gpiochip_request_interrupt, acpi_gpio);
299 EXPORT_SYMBOL_GPL(acpi_gpiochip_request_interrupts);
302 * acpi_gpiochip_free_interrupts() - Free GPIO ACPI event interrupts.
305 * Free interrupts associated with GPIO ACPI event method for the given
308 void acpi_gpiochip_free_interrupts(struct gpio_chip *chip)
310 struct acpi_gpio_chip *acpi_gpio;
311 struct acpi_gpio_event *event, *ep;
315 if (!chip->parent || !chip->to_irq)
318 handle = ACPI_HANDLE(chip->parent);
322 status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
323 if (ACPI_FAILURE(status))
326 mutex_lock(&acpi_gpio_deferred_req_irqs_lock);
327 if (!list_empty(&acpi_gpio->deferred_req_irqs_list_entry))
328 list_del_init(&acpi_gpio->deferred_req_irqs_list_entry);
329 mutex_unlock(&acpi_gpio_deferred_req_irqs_lock);
331 list_for_each_entry_safe_reverse(event, ep, &acpi_gpio->events, node) {
332 struct gpio_desc *desc;
334 if (irqd_is_wakeup_set(irq_get_irq_data(event->irq)))
335 disable_irq_wake(event->irq);
337 free_irq(event->irq, event);
339 if (WARN_ON(IS_ERR(desc)))
341 gpiochip_unlock_as_irq(chip, event->pin);
342 gpiochip_free_own_desc(desc);
343 list_del(&event->node);
347 EXPORT_SYMBOL_GPL(acpi_gpiochip_free_interrupts);
349 int acpi_dev_add_driver_gpios(struct acpi_device *adev,
350 const struct acpi_gpio_mapping *gpios)
353 adev->driver_gpios = gpios;
358 EXPORT_SYMBOL_GPL(acpi_dev_add_driver_gpios);
360 static void devm_acpi_dev_release_driver_gpios(struct device *dev, void *res)
362 acpi_dev_remove_driver_gpios(ACPI_COMPANION(dev));
365 int devm_acpi_dev_add_driver_gpios(struct device *dev,
366 const struct acpi_gpio_mapping *gpios)
371 res = devres_alloc(devm_acpi_dev_release_driver_gpios, 0, GFP_KERNEL);
375 ret = acpi_dev_add_driver_gpios(ACPI_COMPANION(dev), gpios);
380 devres_add(dev, res);
383 EXPORT_SYMBOL_GPL(devm_acpi_dev_add_driver_gpios);
385 void devm_acpi_dev_remove_driver_gpios(struct device *dev)
387 WARN_ON(devres_release(dev, devm_acpi_dev_release_driver_gpios, NULL, NULL));
389 EXPORT_SYMBOL_GPL(devm_acpi_dev_remove_driver_gpios);
391 static bool acpi_get_driver_gpio_data(struct acpi_device *adev,
392 const char *name, int index,
393 struct fwnode_reference_args *args,
394 unsigned int *quirks)
396 const struct acpi_gpio_mapping *gm;
398 if (!adev->driver_gpios)
401 for (gm = adev->driver_gpios; gm->name; gm++)
402 if (!strcmp(name, gm->name) && gm->data && index < gm->size) {
403 const struct acpi_gpio_params *par = gm->data + index;
405 args->fwnode = acpi_fwnode_handle(adev);
406 args->args[0] = par->crs_entry_index;
407 args->args[1] = par->line_index;
408 args->args[2] = par->active_low;
411 *quirks = gm->quirks;
418 static enum gpiod_flags
419 acpi_gpio_to_gpiod_flags(const struct acpi_resource_gpio *agpio)
421 bool pull_up = agpio->pin_config == ACPI_PIN_CONFIG_PULLUP;
423 switch (agpio->io_restriction) {
424 case ACPI_IO_RESTRICT_INPUT:
426 case ACPI_IO_RESTRICT_OUTPUT:
428 * ACPI GPIO resources don't contain an initial value for the
429 * GPIO. Therefore we deduce that value from the pull field
430 * instead. If the pin is pulled up we assume default to be
431 * high, otherwise low.
433 return pull_up ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW;
436 * Assume that the BIOS has configured the direction and pull
444 __acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags, enum gpiod_flags update)
449 * Check if the BIOS has IoRestriction with explicitly set direction
450 * and update @flags accordingly. Otherwise use whatever caller asked
453 if (update & GPIOD_FLAGS_BIT_DIR_SET) {
454 enum gpiod_flags diff = *flags ^ update;
457 * Check if caller supplied incompatible GPIO initialization
460 * Return %-EINVAL to notify that firmware has different
461 * settings and we are going to use them.
463 if (((*flags & GPIOD_FLAGS_BIT_DIR_SET) && (diff & GPIOD_FLAGS_BIT_DIR_OUT)) ||
464 ((*flags & GPIOD_FLAGS_BIT_DIR_OUT) && (diff & GPIOD_FLAGS_BIT_DIR_VAL)))
472 acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags, struct acpi_gpio_info *info)
474 struct device *dev = &info->adev->dev;
475 enum gpiod_flags old = *flags;
478 ret = __acpi_gpio_update_gpiod_flags(&old, info->flags);
479 if (info->quirks & ACPI_GPIO_QUIRK_NO_IO_RESTRICTION) {
481 dev_warn(dev, FW_BUG "GPIO not in correct mode, fixing\n");
484 dev_dbg(dev, "Override GPIO initialization flags\n");
491 struct acpi_gpio_lookup {
492 struct acpi_gpio_info info;
496 struct gpio_desc *desc;
500 static int acpi_populate_gpio_lookup(struct acpi_resource *ares, void *data)
502 struct acpi_gpio_lookup *lookup = data;
504 if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
507 if (lookup->n++ == lookup->index && !lookup->desc) {
508 const struct acpi_resource_gpio *agpio = &ares->data.gpio;
509 int pin_index = lookup->pin_index;
511 if (pin_index >= agpio->pin_table_length)
514 lookup->desc = acpi_get_gpiod(agpio->resource_source.string_ptr,
515 agpio->pin_table[pin_index]);
516 lookup->info.gpioint =
517 agpio->connection_type == ACPI_RESOURCE_GPIO_TYPE_INT;
520 * Polarity and triggering are only specified for GpioInt
522 * Note: we expect here:
523 * - ACPI_ACTIVE_LOW == GPIO_ACTIVE_LOW
524 * - ACPI_ACTIVE_HIGH == GPIO_ACTIVE_HIGH
526 if (lookup->info.gpioint) {
527 lookup->info.flags = GPIOD_IN;
528 lookup->info.polarity = agpio->polarity;
529 lookup->info.triggering = agpio->triggering;
531 lookup->info.flags = acpi_gpio_to_gpiod_flags(agpio);
532 lookup->info.polarity = lookup->active_low;
539 static int acpi_gpio_resource_lookup(struct acpi_gpio_lookup *lookup,
540 struct acpi_gpio_info *info)
542 struct acpi_device *adev = lookup->info.adev;
543 struct list_head res_list;
546 INIT_LIST_HEAD(&res_list);
548 ret = acpi_dev_get_resources(adev, &res_list,
549 acpi_populate_gpio_lookup,
554 acpi_dev_free_resource_list(&res_list);
560 *info = lookup->info;
564 static int acpi_gpio_property_lookup(struct fwnode_handle *fwnode,
565 const char *propname, int index,
566 struct acpi_gpio_lookup *lookup)
568 struct fwnode_reference_args args;
569 unsigned int quirks = 0;
572 memset(&args, 0, sizeof(args));
573 ret = __acpi_node_get_property_reference(fwnode, propname, index, 3,
576 struct acpi_device *adev = to_acpi_device_node(fwnode);
581 if (!acpi_get_driver_gpio_data(adev, propname, index, &args,
586 * The property was found and resolved, so need to lookup the GPIO based
589 if (!to_acpi_device_node(args.fwnode))
594 lookup->index = args.args[0];
595 lookup->pin_index = args.args[1];
596 lookup->active_low = !!args.args[2];
598 lookup->info.adev = to_acpi_device_node(args.fwnode);
599 lookup->info.quirks = quirks;
605 * acpi_get_gpiod_by_index() - get a GPIO descriptor from device resources
606 * @adev: pointer to a ACPI device to get GPIO from
607 * @propname: Property name of the GPIO (optional)
608 * @index: index of GpioIo/GpioInt resource (starting from %0)
609 * @info: info pointer to fill in (optional)
611 * Function goes through ACPI resources for @adev and based on @index looks
612 * up a GpioIo/GpioInt resource, translates it to the Linux GPIO descriptor,
613 * and returns it. @index matches GpioIo/GpioInt resources only so if there
614 * are total %3 GPIO resources, the index goes from %0 to %2.
616 * If @propname is specified the GPIO is looked using device property. In
617 * that case @index is used to select the GPIO entry in the property value
618 * (in case of multiple).
620 * If the GPIO cannot be translated or there is an error an ERR_PTR is
623 * Note: if the GPIO resource has multiple entries in the pin list, this
624 * function only returns the first.
626 static struct gpio_desc *acpi_get_gpiod_by_index(struct acpi_device *adev,
627 const char *propname, int index,
628 struct acpi_gpio_info *info)
630 struct acpi_gpio_lookup lookup;
634 return ERR_PTR(-ENODEV);
636 memset(&lookup, 0, sizeof(lookup));
637 lookup.index = index;
640 dev_dbg(&adev->dev, "GPIO: looking up %s\n", propname);
642 ret = acpi_gpio_property_lookup(acpi_fwnode_handle(adev),
643 propname, index, &lookup);
647 dev_dbg(&adev->dev, "GPIO: _DSD returned %s %d %d %u\n",
648 dev_name(&lookup.info.adev->dev), lookup.index,
649 lookup.pin_index, lookup.active_low);
651 dev_dbg(&adev->dev, "GPIO: looking up %d in _CRS\n", index);
652 lookup.info.adev = adev;
655 ret = acpi_gpio_resource_lookup(&lookup, info);
656 return ret ? ERR_PTR(ret) : lookup.desc;
659 struct gpio_desc *acpi_find_gpio(struct device *dev,
662 enum gpiod_flags *dflags,
663 enum gpio_lookup_flags *lookupflags)
665 struct acpi_device *adev = ACPI_COMPANION(dev);
666 struct acpi_gpio_info info;
667 struct gpio_desc *desc;
671 /* Try first from _DSD */
672 for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
674 snprintf(propname, sizeof(propname), "%s-%s",
675 con_id, gpio_suffixes[i]);
677 snprintf(propname, sizeof(propname), "%s",
681 desc = acpi_get_gpiod_by_index(adev, propname, idx, &info);
684 if (PTR_ERR(desc) == -EPROBE_DEFER)
685 return ERR_CAST(desc);
688 /* Then from plain _CRS GPIOs */
690 if (!acpi_can_fallback_to_crs(adev, con_id))
691 return ERR_PTR(-ENOENT);
693 desc = acpi_get_gpiod_by_index(adev, NULL, idx, &info);
699 (*dflags == GPIOD_OUT_LOW || *dflags == GPIOD_OUT_HIGH)) {
700 dev_dbg(dev, "refusing GpioInt() entry when doing GPIOD_OUT_* lookup\n");
701 return ERR_PTR(-ENOENT);
704 if (info.polarity == GPIO_ACTIVE_LOW)
705 *lookupflags |= GPIO_ACTIVE_LOW;
707 acpi_gpio_update_gpiod_flags(dflags, &info);
712 * acpi_node_get_gpiod() - get a GPIO descriptor from ACPI resources
713 * @fwnode: pointer to an ACPI firmware node to get the GPIO information from
714 * @propname: Property name of the GPIO
715 * @index: index of GpioIo/GpioInt resource (starting from %0)
716 * @info: info pointer to fill in (optional)
718 * If @fwnode is an ACPI device object, call %acpi_get_gpiod_by_index() for it.
719 * Otherwise (ie. it is a data-only non-device object), use the property-based
720 * GPIO lookup to get to the GPIO resource with the relevant information and use
721 * that to obtain the GPIO descriptor to return.
723 struct gpio_desc *acpi_node_get_gpiod(struct fwnode_handle *fwnode,
724 const char *propname, int index,
725 struct acpi_gpio_info *info)
727 struct acpi_gpio_lookup lookup;
728 struct acpi_device *adev;
731 adev = to_acpi_device_node(fwnode);
733 return acpi_get_gpiod_by_index(adev, propname, index, info);
735 if (!is_acpi_data_node(fwnode))
736 return ERR_PTR(-ENODEV);
739 return ERR_PTR(-EINVAL);
741 memset(&lookup, 0, sizeof(lookup));
742 lookup.index = index;
744 ret = acpi_gpio_property_lookup(fwnode, propname, index, &lookup);
748 ret = acpi_gpio_resource_lookup(&lookup, info);
749 return ret ? ERR_PTR(ret) : lookup.desc;
753 * acpi_dev_gpio_irq_get() - Find GpioInt and translate it to Linux IRQ number
754 * @adev: pointer to a ACPI device to get IRQ from
755 * @index: index of GpioInt resource (starting from %0)
757 * If the device has one or more GpioInt resources, this function can be
758 * used to translate from the GPIO offset in the resource to the Linux IRQ
761 * The function is idempotent, though each time it runs it will configure GPIO
762 * pin direction according to the flags in GpioInt resource.
764 * Return: Linux IRQ number (> %0) on success, negative errno on failure.
766 int acpi_dev_gpio_irq_get(struct acpi_device *adev, int index)
769 unsigned int irq_flags;
772 for (i = 0, idx = 0; idx <= index; i++) {
773 struct acpi_gpio_info info;
774 struct gpio_desc *desc;
776 desc = acpi_get_gpiod_by_index(adev, NULL, i, &info);
778 /* Ignore -EPROBE_DEFER, it only matters if idx matches */
779 if (IS_ERR(desc) && PTR_ERR(desc) != -EPROBE_DEFER)
780 return PTR_ERR(desc);
782 if (info.gpioint && idx++ == index) {
787 return PTR_ERR(desc);
789 irq = gpiod_to_irq(desc);
793 snprintf(label, sizeof(label), "GpioInt() %d", index);
794 ret = gpiod_configure_flags(desc, label, 0, info.flags);
798 irq_flags = acpi_dev_get_irq_type(info.triggering,
801 /* Set type if specified and different than the current one */
802 if (irq_flags != IRQ_TYPE_NONE &&
803 irq_flags != irq_get_trigger_type(irq))
804 irq_set_irq_type(irq, irq_flags);
812 EXPORT_SYMBOL_GPL(acpi_dev_gpio_irq_get);
815 acpi_gpio_adr_space_handler(u32 function, acpi_physical_address address,
816 u32 bits, u64 *value, void *handler_context,
817 void *region_context)
819 struct acpi_gpio_chip *achip = region_context;
820 struct gpio_chip *chip = achip->chip;
821 struct acpi_resource_gpio *agpio;
822 struct acpi_resource *ares;
823 int pin_index = (int)address;
828 status = acpi_buffer_to_resource(achip->conn_info.connection,
829 achip->conn_info.length, &ares);
830 if (ACPI_FAILURE(status))
833 if (WARN_ON(ares->type != ACPI_RESOURCE_TYPE_GPIO)) {
835 return AE_BAD_PARAMETER;
838 agpio = &ares->data.gpio;
840 if (WARN_ON(agpio->io_restriction == ACPI_IO_RESTRICT_INPUT &&
841 function == ACPI_WRITE)) {
843 return AE_BAD_PARAMETER;
846 length = min(agpio->pin_table_length, (u16)(pin_index + bits));
847 for (i = pin_index; i < length; ++i) {
848 int pin = agpio->pin_table[i];
849 struct acpi_gpio_connection *conn;
850 struct gpio_desc *desc;
853 mutex_lock(&achip->conn_lock);
856 list_for_each_entry(conn, &achip->conns, node) {
857 if (conn->pin == pin) {
865 * The same GPIO can be shared between operation region and
866 * event but only if the access here is ACPI_READ. In that
867 * case we "borrow" the event GPIO instead.
869 if (!found && agpio->sharable == ACPI_SHARED &&
870 function == ACPI_READ) {
871 struct acpi_gpio_event *event;
873 list_for_each_entry(event, &achip->events, node) {
874 if (event->pin == pin) {
883 enum gpiod_flags flags = acpi_gpio_to_gpiod_flags(agpio);
884 const char *label = "ACPI:OpRegion";
887 desc = gpiochip_request_own_desc(chip, pin, label);
890 mutex_unlock(&achip->conn_lock);
894 err = gpiod_configure_flags(desc, label, 0, flags);
896 status = AE_NOT_CONFIGURED;
897 gpiochip_free_own_desc(desc);
898 mutex_unlock(&achip->conn_lock);
902 conn = kzalloc(sizeof(*conn), GFP_KERNEL);
904 status = AE_NO_MEMORY;
905 gpiochip_free_own_desc(desc);
906 mutex_unlock(&achip->conn_lock);
912 list_add_tail(&conn->node, &achip->conns);
915 mutex_unlock(&achip->conn_lock);
917 if (function == ACPI_WRITE)
918 gpiod_set_raw_value_cansleep(desc,
919 !!((1 << i) & *value));
921 *value |= (u64)gpiod_get_raw_value_cansleep(desc) << i;
929 static void acpi_gpiochip_request_regions(struct acpi_gpio_chip *achip)
931 struct gpio_chip *chip = achip->chip;
932 acpi_handle handle = ACPI_HANDLE(chip->parent);
935 INIT_LIST_HEAD(&achip->conns);
936 mutex_init(&achip->conn_lock);
937 status = acpi_install_address_space_handler(handle, ACPI_ADR_SPACE_GPIO,
938 acpi_gpio_adr_space_handler,
940 if (ACPI_FAILURE(status))
941 dev_err(chip->parent,
942 "Failed to install GPIO OpRegion handler\n");
945 static void acpi_gpiochip_free_regions(struct acpi_gpio_chip *achip)
947 struct gpio_chip *chip = achip->chip;
948 acpi_handle handle = ACPI_HANDLE(chip->parent);
949 struct acpi_gpio_connection *conn, *tmp;
952 status = acpi_remove_address_space_handler(handle, ACPI_ADR_SPACE_GPIO,
953 acpi_gpio_adr_space_handler);
954 if (ACPI_FAILURE(status)) {
955 dev_err(chip->parent,
956 "Failed to remove GPIO OpRegion handler\n");
960 list_for_each_entry_safe_reverse(conn, tmp, &achip->conns, node) {
961 gpiochip_free_own_desc(conn->desc);
962 list_del(&conn->node);
967 static struct gpio_desc *acpi_gpiochip_parse_own_gpio(
968 struct acpi_gpio_chip *achip, struct fwnode_handle *fwnode,
969 const char **name, unsigned int *lflags, unsigned int *dflags)
971 struct gpio_chip *chip = achip->chip;
972 struct gpio_desc *desc;
980 ret = fwnode_property_read_u32_array(fwnode, "gpios", gpios,
985 desc = gpiochip_get_desc(chip, gpios[0]);
990 *lflags |= GPIO_ACTIVE_LOW;
992 if (fwnode_property_present(fwnode, "input"))
994 else if (fwnode_property_present(fwnode, "output-low"))
995 *dflags |= GPIOD_OUT_LOW;
996 else if (fwnode_property_present(fwnode, "output-high"))
997 *dflags |= GPIOD_OUT_HIGH;
999 return ERR_PTR(-EINVAL);
1001 fwnode_property_read_string(fwnode, "line-name", name);
1006 static void acpi_gpiochip_scan_gpios(struct acpi_gpio_chip *achip)
1008 struct gpio_chip *chip = achip->chip;
1009 struct fwnode_handle *fwnode;
1011 device_for_each_child_node(chip->parent, fwnode) {
1012 unsigned int lflags, dflags;
1013 struct gpio_desc *desc;
1017 if (!fwnode_property_present(fwnode, "gpio-hog"))
1020 desc = acpi_gpiochip_parse_own_gpio(achip, fwnode, &name,
1025 ret = gpiod_hog(desc, name, lflags, dflags);
1027 dev_err(chip->parent, "Failed to hog GPIO\n");
1028 fwnode_handle_put(fwnode);
1034 void acpi_gpiochip_add(struct gpio_chip *chip)
1036 struct acpi_gpio_chip *acpi_gpio;
1040 if (!chip || !chip->parent)
1043 handle = ACPI_HANDLE(chip->parent);
1047 acpi_gpio = kzalloc(sizeof(*acpi_gpio), GFP_KERNEL);
1049 dev_err(chip->parent,
1050 "Failed to allocate memory for ACPI GPIO chip\n");
1054 acpi_gpio->chip = chip;
1055 INIT_LIST_HEAD(&acpi_gpio->events);
1056 INIT_LIST_HEAD(&acpi_gpio->deferred_req_irqs_list_entry);
1058 status = acpi_attach_data(handle, acpi_gpio_chip_dh, acpi_gpio);
1059 if (ACPI_FAILURE(status)) {
1060 dev_err(chip->parent, "Failed to attach ACPI GPIO chip\n");
1066 devprop_gpiochip_set_names(chip, dev_fwnode(chip->parent));
1068 acpi_gpiochip_request_regions(acpi_gpio);
1069 acpi_gpiochip_scan_gpios(acpi_gpio);
1070 acpi_walk_dep_device_list(handle);
1073 void acpi_gpiochip_remove(struct gpio_chip *chip)
1075 struct acpi_gpio_chip *acpi_gpio;
1079 if (!chip || !chip->parent)
1082 handle = ACPI_HANDLE(chip->parent);
1086 status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
1087 if (ACPI_FAILURE(status)) {
1088 dev_warn(chip->parent, "Failed to retrieve ACPI GPIO chip\n");
1092 acpi_gpiochip_free_regions(acpi_gpio);
1094 acpi_detach_data(handle, acpi_gpio_chip_dh);
1098 static int acpi_gpio_package_count(const union acpi_object *obj)
1100 const union acpi_object *element = obj->package.elements;
1101 const union acpi_object *end = element + obj->package.count;
1102 unsigned int count = 0;
1104 while (element < end) {
1105 switch (element->type) {
1106 case ACPI_TYPE_LOCAL_REFERENCE:
1109 case ACPI_TYPE_INTEGER:
1122 static int acpi_find_gpio_count(struct acpi_resource *ares, void *data)
1124 unsigned int *count = data;
1126 if (ares->type == ACPI_RESOURCE_TYPE_GPIO)
1127 *count += ares->data.gpio.pin_table_length;
1133 * acpi_gpio_count - return the number of GPIOs associated with a
1134 * device / function or -ENOENT if no GPIO has been
1135 * assigned to the requested function.
1136 * @dev: GPIO consumer, can be NULL for system-global GPIOs
1137 * @con_id: function within the GPIO consumer
1139 int acpi_gpio_count(struct device *dev, const char *con_id)
1141 struct acpi_device *adev = ACPI_COMPANION(dev);
1142 const union acpi_object *obj;
1143 const struct acpi_gpio_mapping *gm;
1144 int count = -ENOENT;
1149 /* Try first from _DSD */
1150 for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
1152 snprintf(propname, sizeof(propname), "%s-%s",
1153 con_id, gpio_suffixes[i]);
1155 snprintf(propname, sizeof(propname), "%s",
1158 ret = acpi_dev_get_property(adev, propname, ACPI_TYPE_ANY,
1161 if (obj->type == ACPI_TYPE_LOCAL_REFERENCE)
1163 else if (obj->type == ACPI_TYPE_PACKAGE)
1164 count = acpi_gpio_package_count(obj);
1165 } else if (adev->driver_gpios) {
1166 for (gm = adev->driver_gpios; gm->name; gm++)
1167 if (strcmp(propname, gm->name) == 0) {
1176 /* Then from plain _CRS GPIOs */
1178 struct list_head resource_list;
1179 unsigned int crs_count = 0;
1181 if (!acpi_can_fallback_to_crs(adev, con_id))
1184 INIT_LIST_HEAD(&resource_list);
1185 acpi_dev_get_resources(adev, &resource_list,
1186 acpi_find_gpio_count, &crs_count);
1187 acpi_dev_free_resource_list(&resource_list);
1191 return count ? count : -ENOENT;
1194 bool acpi_can_fallback_to_crs(struct acpi_device *adev, const char *con_id)
1196 /* Never allow fallback if the device has properties */
1197 if (acpi_dev_has_props(adev) || adev->driver_gpios)
1200 return con_id == NULL;
1203 /* Run deferred acpi_gpiochip_request_interrupts() */
1204 static int acpi_gpio_handle_deferred_request_interrupts(void)
1206 struct acpi_gpio_chip *acpi_gpio, *tmp;
1208 mutex_lock(&acpi_gpio_deferred_req_irqs_lock);
1209 list_for_each_entry_safe(acpi_gpio, tmp,
1210 &acpi_gpio_deferred_req_irqs_list,
1211 deferred_req_irqs_list_entry) {
1214 handle = ACPI_HANDLE(acpi_gpio->chip->parent);
1215 acpi_walk_resources(handle, "_AEI",
1216 acpi_gpiochip_request_interrupt, acpi_gpio);
1218 list_del_init(&acpi_gpio->deferred_req_irqs_list_entry);
1221 acpi_gpio_deferred_req_irqs_done = true;
1222 mutex_unlock(&acpi_gpio_deferred_req_irqs_lock);
1226 /* We must use _sync so that this runs after the first deferred_probe run */
1227 late_initcall_sync(acpi_gpio_handle_deferred_request_interrupts);