// SPDX-License-Identifier: GPL-2.0 /* * ACPI helpers for GPIO API * * Copyright (C) 2012, Intel Corporation * Authors: Mathias Nyman * Mika Westerberg */ #include #include #include #include #include #include #include #include #include #include "gpiolib.h" /** * struct acpi_gpio_event - ACPI GPIO event handler data * * @node: list-entry of the events list of the struct acpi_gpio_chip * @handle: handle of ACPI method to execute when the IRQ triggers * @handler: irq_handler to pass to request_irq when requesting the IRQ * @pin: GPIO pin number on the gpio_chip * @irq: Linux IRQ number for the event, for request_ / free_irq * @irqflags: flags to pass to request_irq when requesting the IRQ * @irq_is_wake: If the ACPI flags indicate the IRQ is a wakeup source * @is_requested: True if request_irq has been done * @desc: gpio_desc for the GPIO pin for this event */ struct acpi_gpio_event { struct list_head node; acpi_handle handle; irq_handler_t handler; unsigned int pin; unsigned int irq; unsigned long irqflags; bool irq_is_wake; bool irq_requested; struct gpio_desc *desc; }; struct acpi_gpio_connection { struct list_head node; unsigned int pin; struct gpio_desc *desc; }; struct acpi_gpio_chip { /* * ACPICA requires that the first field of the context parameter * passed to acpi_install_address_space_handler() is large enough * to hold struct acpi_connection_info. */ struct acpi_connection_info conn_info; struct list_head conns; struct mutex conn_lock; struct gpio_chip *chip; struct list_head events; struct list_head deferred_req_irqs_list_entry; }; /* * For gpiochips which call acpi_gpiochip_request_interrupts() before late_init * (so builtin drivers) we register the ACPI GpioInt IRQ handlers from a * late_initcall_sync handler, so that other builtin drivers can register their * OpRegions before the event handlers can run. This list contains gpiochips * for which the acpi_gpiochip_request_irqs() call has been deferred. */ static DEFINE_MUTEX(acpi_gpio_deferred_req_irqs_lock); static LIST_HEAD(acpi_gpio_deferred_req_irqs_list); static bool acpi_gpio_deferred_req_irqs_done; static int acpi_gpiochip_find(struct gpio_chip *gc, void *data) { if (!gc->parent) return false; return ACPI_HANDLE(gc->parent) == data; } /** * acpi_get_gpiod() - Translate ACPI GPIO pin to GPIO descriptor usable with GPIO API * @path: ACPI GPIO controller full path name, (e.g. "\\_SB.GPO1") * @pin: ACPI GPIO pin number (0-based, controller-relative) * * Return: GPIO descriptor to use with Linux generic GPIO API, or ERR_PTR * error value. Specifically returns %-EPROBE_DEFER if the referenced GPIO * controller does not have gpiochip registered at the moment. This is to * support probe deferral. */ static struct gpio_desc *acpi_get_gpiod(char *path, int pin) { struct gpio_chip *chip; acpi_handle handle; acpi_status status; status = acpi_get_handle(NULL, path, &handle); if (ACPI_FAILURE(status)) return ERR_PTR(-ENODEV); chip = gpiochip_find(handle, acpi_gpiochip_find); if (!chip) return ERR_PTR(-EPROBE_DEFER); return gpiochip_get_desc(chip, pin); } static irqreturn_t acpi_gpio_irq_handler(int irq, void *data) { struct acpi_gpio_event *event = data; acpi_evaluate_object(event->handle, NULL, NULL, NULL); return IRQ_HANDLED; } static irqreturn_t acpi_gpio_irq_handler_evt(int irq, void *data) { struct acpi_gpio_event *event = data; acpi_execute_simple_method(event->handle, NULL, event->pin); return IRQ_HANDLED; } static void acpi_gpio_chip_dh(acpi_handle handle, void *data) { /* The address of this function is used as a key. */ } bool acpi_gpio_get_irq_resource(struct acpi_resource *ares, struct acpi_resource_gpio **agpio) { struct acpi_resource_gpio *gpio; if (ares->type != ACPI_RESOURCE_TYPE_GPIO) return false; gpio = &ares->data.gpio; if (gpio->connection_type != ACPI_RESOURCE_GPIO_TYPE_INT) return false; *agpio = gpio; return true; } EXPORT_SYMBOL_GPL(acpi_gpio_get_irq_resource); static void acpi_gpiochip_request_irq(struct acpi_gpio_chip *acpi_gpio, struct acpi_gpio_event *event) { int ret, value; ret = request_threaded_irq(event->irq, NULL, event->handler, event->irqflags, "ACPI:Event", event); if (ret) { dev_err(acpi_gpio->chip->parent, "Failed to setup interrupt handler for %d\n", event->irq); return; } if (event->irq_is_wake) enable_irq_wake(event->irq); event->irq_requested = true; /* Make sure we trigger the initial state of edge-triggered IRQs */ value = gpiod_get_raw_value_cansleep(event->desc); if (((event->irqflags & IRQF_TRIGGER_RISING) && value == 1) || ((event->irqflags & IRQF_TRIGGER_FALLING) && value == 0)) event->handler(event->irq, event); } static void acpi_gpiochip_request_irqs(struct acpi_gpio_chip *acpi_gpio) { struct acpi_gpio_event *event; list_for_each_entry(event, &acpi_gpio->events, node) acpi_gpiochip_request_irq(acpi_gpio, event); } static acpi_status acpi_gpiochip_alloc_event(struct acpi_resource *ares, void *context) { struct acpi_gpio_chip *acpi_gpio = context; struct gpio_chip *chip = acpi_gpio->chip; struct acpi_resource_gpio *agpio; acpi_handle handle, evt_handle; struct acpi_gpio_event *event; irq_handler_t handler = NULL; struct gpio_desc *desc; int ret, pin, irq; if (!acpi_gpio_get_irq_resource(ares, &agpio)) return AE_OK; handle = ACPI_HANDLE(chip->parent); pin = agpio->pin_table[0]; if (pin <= 255) { char ev_name[5]; sprintf(ev_name, "_%c%02hhX", agpio->triggering == ACPI_EDGE_SENSITIVE ? 'E' : 'L', pin); if (ACPI_SUCCESS(acpi_get_handle(handle, ev_name, &evt_handle))) handler = acpi_gpio_irq_handler; } if (!handler) { if (ACPI_SUCCESS(acpi_get_handle(handle, "_EVT", &evt_handle))) handler = acpi_gpio_irq_handler_evt; } if (!handler) return AE_OK; desc = gpiochip_request_own_desc(chip, pin, "ACPI:Event", 0); if (IS_ERR(desc)) { dev_err(chip->parent, "Failed to request GPIO\n"); return AE_ERROR; } gpiod_direction_input(desc); ret = gpiochip_lock_as_irq(chip, pin); if (ret) { dev_err(chip->parent, "Failed to lock GPIO as interrupt\n"); goto fail_free_desc; } irq = gpiod_to_irq(desc); if (irq < 0) { dev_err(chip->parent, "Failed to translate GPIO to IRQ\n"); goto fail_unlock_irq; } event = kzalloc(sizeof(*event), GFP_KERNEL); if (!event) goto fail_unlock_irq; event->irqflags = IRQF_ONESHOT; if (agpio->triggering == ACPI_LEVEL_SENSITIVE) { if (agpio->polarity == ACPI_ACTIVE_HIGH) event->irqflags |= IRQF_TRIGGER_HIGH; else event->irqflags |= IRQF_TRIGGER_LOW; } else { switch (agpio->polarity) { case ACPI_ACTIVE_HIGH: event->irqflags |= IRQF_TRIGGER_RISING; break; case ACPI_ACTIVE_LOW: event->irqflags |= IRQF_TRIGGER_FALLING; break; default: event->irqflags |= IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING; break; } } event->handle = evt_handle; event->handler = handler; event->irq = irq; event->irq_is_wake = agpio->wake_capable == ACPI_WAKE_CAPABLE; event->pin = pin; event->desc = desc; list_add_tail(&event->node, &acpi_gpio->events); return AE_OK; fail_unlock_irq: gpiochip_unlock_as_irq(chip, pin); fail_free_desc: gpiochip_free_own_desc(desc); return AE_ERROR; } /** * acpi_gpiochip_request_interrupts() - Register isr for gpio chip ACPI events * @chip: GPIO chip * * ACPI5 platforms can use GPIO signaled ACPI events. These GPIO interrupts are * handled by ACPI event methods which need to be called from the GPIO * chip's interrupt handler. acpi_gpiochip_request_interrupts finds out which * gpio pins have acpi event methods and assigns interrupt handlers that calls * the acpi event methods for those pins. */ void acpi_gpiochip_request_interrupts(struct gpio_chip *chip) { struct acpi_gpio_chip *acpi_gpio; acpi_handle handle; acpi_status status; bool defer; if (!chip->parent || !chip->to_irq) return; handle = ACPI_HANDLE(chip->parent); if (!handle) return; status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio); if (ACPI_FAILURE(status)) return; acpi_walk_resources(handle, "_AEI", acpi_gpiochip_alloc_event, acpi_gpio); mutex_lock(&acpi_gpio_deferred_req_irqs_lock); defer = !acpi_gpio_deferred_req_irqs_done; if (defer) list_add(&acpi_gpio->deferred_req_irqs_list_entry, &acpi_gpio_deferred_req_irqs_list); mutex_unlock(&acpi_gpio_deferred_req_irqs_lock); if (defer) return; acpi_gpiochip_request_irqs(acpi_gpio); } EXPORT_SYMBOL_GPL(acpi_gpiochip_request_interrupts); /** * acpi_gpiochip_free_interrupts() - Free GPIO ACPI event interrupts. * @chip: GPIO chip * * Free interrupts associated with GPIO ACPI event method for the given * GPIO chip. */ void acpi_gpiochip_free_interrupts(struct gpio_chip *chip) { struct acpi_gpio_chip *acpi_gpio; struct acpi_gpio_event *event, *ep; acpi_handle handle; acpi_status status; if (!chip->parent || !chip->to_irq) return; handle = ACPI_HANDLE(chip->parent); if (!handle) return; status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio); if (ACPI_FAILURE(status)) return; mutex_lock(&acpi_gpio_deferred_req_irqs_lock); if (!list_empty(&acpi_gpio->deferred_req_irqs_list_entry)) list_del_init(&acpi_gpio->deferred_req_irqs_list_entry); mutex_unlock(&acpi_gpio_deferred_req_irqs_lock); list_for_each_entry_safe_reverse(event, ep, &acpi_gpio->events, node) { if (event->irq_requested) { if (event->irq_is_wake) disable_irq_wake(event->irq); free_irq(event->irq, event); } gpiochip_unlock_as_irq(chip, event->pin); gpiochip_free_own_desc(event->desc); list_del(&event->node); kfree(event); } } EXPORT_SYMBOL_GPL(acpi_gpiochip_free_interrupts); int acpi_dev_add_driver_gpios(struct acpi_device *adev, const struct acpi_gpio_mapping *gpios) { if (adev && gpios) { adev->driver_gpios = gpios; return 0; } return -EINVAL; } EXPORT_SYMBOL_GPL(acpi_dev_add_driver_gpios); static void devm_acpi_dev_release_driver_gpios(struct device *dev, void *res) { acpi_dev_remove_driver_gpios(ACPI_COMPANION(dev)); } int devm_acpi_dev_add_driver_gpios(struct device *dev, const struct acpi_gpio_mapping *gpios) { void *res; int ret; res = devres_alloc(devm_acpi_dev_release_driver_gpios, 0, GFP_KERNEL); if (!res) return -ENOMEM; ret = acpi_dev_add_driver_gpios(ACPI_COMPANION(dev), gpios); if (ret) { devres_free(res); return ret; } devres_add(dev, res); return 0; } EXPORT_SYMBOL_GPL(devm_acpi_dev_add_driver_gpios); void devm_acpi_dev_remove_driver_gpios(struct device *dev) { WARN_ON(devres_release(dev, devm_acpi_dev_release_driver_gpios, NULL, NULL)); } EXPORT_SYMBOL_GPL(devm_acpi_dev_remove_driver_gpios); static bool acpi_get_driver_gpio_data(struct acpi_device *adev, const char *name, int index, struct fwnode_reference_args *args, unsigned int *quirks) { const struct acpi_gpio_mapping *gm; if (!adev->driver_gpios) return false; for (gm = adev->driver_gpios; gm->name; gm++) if (!strcmp(name, gm->name) && gm->data && index < gm->size) { const struct acpi_gpio_params *par = gm->data + index; args->fwnode = acpi_fwnode_handle(adev); args->args[0] = par->crs_entry_index; args->args[1] = par->line_index; args->args[2] = par->active_low; args->nargs = 3; *quirks = gm->quirks; return true; } return false; } static enum gpiod_flags acpi_gpio_to_gpiod_flags(const struct acpi_resource_gpio *agpio) { bool pull_up = agpio->pin_config == ACPI_PIN_CONFIG_PULLUP; switch (agpio->io_restriction) { case ACPI_IO_RESTRICT_INPUT: return GPIOD_IN; case ACPI_IO_RESTRICT_OUTPUT: /* * ACPI GPIO resources don't contain an initial value for the * GPIO. Therefore we deduce that value from the pull field * instead. If the pin is pulled up we assume default to be * high, otherwise low. */ return pull_up ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW; default: /* * Assume that the BIOS has configured the direction and pull * accordingly. */ return GPIOD_ASIS; } } static int __acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags, enum gpiod_flags update) { int ret = 0; /* * Check if the BIOS has IoRestriction with explicitly set direction * and update @flags accordingly. Otherwise use whatever caller asked * for. */ if (update & GPIOD_FLAGS_BIT_DIR_SET) { enum gpiod_flags diff = *flags ^ update; /* * Check if caller supplied incompatible GPIO initialization * flags. * * Return %-EINVAL to notify that firmware has different * settings and we are going to use them. */ if (((*flags & GPIOD_FLAGS_BIT_DIR_SET) && (diff & GPIOD_FLAGS_BIT_DIR_OUT)) || ((*flags & GPIOD_FLAGS_BIT_DIR_OUT) && (diff & GPIOD_FLAGS_BIT_DIR_VAL))) ret = -EINVAL; *flags = update; } return ret; } int acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags, struct acpi_gpio_info *info) { struct device *dev = &info->adev->dev; enum gpiod_flags old = *flags; int ret; ret = __acpi_gpio_update_gpiod_flags(&old, info->flags); if (info->quirks & ACPI_GPIO_QUIRK_NO_IO_RESTRICTION) { if (ret) dev_warn(dev, FW_BUG "GPIO not in correct mode, fixing\n"); } else { if (ret) dev_dbg(dev, "Override GPIO initialization flags\n"); *flags = old; } return ret; } struct acpi_gpio_lookup { struct acpi_gpio_info info; int index; int pin_index; bool active_low; struct gpio_desc *desc; int n; }; static int acpi_populate_gpio_lookup(struct acpi_resource *ares, void *data) { struct acpi_gpio_lookup *lookup = data; if (ares->type != ACPI_RESOURCE_TYPE_GPIO) return 1; if (lookup->n++ == lookup->index && !lookup->desc) { const struct acpi_resource_gpio *agpio = &ares->data.gpio; int pin_index = lookup->pin_index; if (pin_index >= agpio->pin_table_length) return 1; lookup->desc = acpi_get_gpiod(agpio->resource_source.string_ptr, agpio->pin_table[pin_index]); lookup->info.gpioint = agpio->connection_type == ACPI_RESOURCE_GPIO_TYPE_INT; /* * Polarity and triggering are only specified for GpioInt * resource. * Note: we expect here: * - ACPI_ACTIVE_LOW == GPIO_ACTIVE_LOW * - ACPI_ACTIVE_HIGH == GPIO_ACTIVE_HIGH */ if (lookup->info.gpioint) { lookup->info.flags = GPIOD_IN; lookup->info.polarity = agpio->polarity; lookup->info.triggering = agpio->triggering; } else { lookup->info.flags = acpi_gpio_to_gpiod_flags(agpio); lookup->info.polarity = lookup->active_low; } } return 1; } static int acpi_gpio_resource_lookup(struct acpi_gpio_lookup *lookup, struct acpi_gpio_info *info) { struct acpi_device *adev = lookup->info.adev; struct list_head res_list; int ret; INIT_LIST_HEAD(&res_list); ret = acpi_dev_get_resources(adev, &res_list, acpi_populate_gpio_lookup, lookup); if (ret < 0) return ret; acpi_dev_free_resource_list(&res_list); if (!lookup->desc) return -ENOENT; if (info) *info = lookup->info; return 0; } static int acpi_gpio_property_lookup(struct fwnode_handle *fwnode, const char *propname, int index, struct acpi_gpio_lookup *lookup) { struct fwnode_reference_args args; unsigned int quirks = 0; int ret; memset(&args, 0, sizeof(args)); ret = __acpi_node_get_property_reference(fwnode, propname, index, 3, &args); if (ret) { struct acpi_device *adev = to_acpi_device_node(fwnode); if (!adev) return ret; if (!acpi_get_driver_gpio_data(adev, propname, index, &args, &quirks)) return ret; } /* * The property was found and resolved, so need to lookup the GPIO based * on returned args. */ if (!to_acpi_device_node(args.fwnode)) return -EINVAL; if (args.nargs != 3) return -EPROTO; lookup->index = args.args[0]; lookup->pin_index = args.args[1]; lookup->active_low = !!args.args[2]; lookup->info.adev = to_acpi_device_node(args.fwnode); lookup->info.quirks = quirks; return 0; } /** * acpi_get_gpiod_by_index() - get a GPIO descriptor from device resources * @adev: pointer to a ACPI device to get GPIO from * @propname: Property name of the GPIO (optional) * @index: index of GpioIo/GpioInt resource (starting from %0) * @info: info pointer to fill in (optional) * * Function goes through ACPI resources for @adev and based on @index looks * up a GpioIo/GpioInt resource, translates it to the Linux GPIO descriptor, * and returns it. @index matches GpioIo/GpioInt resources only so if there * are total %3 GPIO resources, the index goes from %0 to %2. * * If @propname is specified the GPIO is looked using device property. In * that case @index is used to select the GPIO entry in the property value * (in case of multiple). * * If the GPIO cannot be translated or there is an error an ERR_PTR is * returned. * * Note: if the GPIO resource has multiple entries in the pin list, this * function only returns the first. */ static struct gpio_desc *acpi_get_gpiod_by_index(struct acpi_device *adev, const char *propname, int index, struct acpi_gpio_info *info) { struct acpi_gpio_lookup lookup; int ret; if (!adev) return ERR_PTR(-ENODEV); memset(&lookup, 0, sizeof(lookup)); lookup.index = index; if (propname) { dev_dbg(&adev->dev, "GPIO: looking up %s\n", propname); ret = acpi_gpio_property_lookup(acpi_fwnode_handle(adev), propname, index, &lookup); if (ret) return ERR_PTR(ret); dev_dbg(&adev->dev, "GPIO: _DSD returned %s %d %d %u\n", dev_name(&lookup.info.adev->dev), lookup.index, lookup.pin_index, lookup.active_low); } else { dev_dbg(&adev->dev, "GPIO: looking up %d in _CRS\n", index); lookup.info.adev = adev; } ret = acpi_gpio_resource_lookup(&lookup, info); return ret ? ERR_PTR(ret) : lookup.desc; } struct gpio_desc *acpi_find_gpio(struct device *dev, const char *con_id, unsigned int idx, enum gpiod_flags *dflags, enum gpio_lookup_flags *lookupflags) { struct acpi_device *adev = ACPI_COMPANION(dev); struct acpi_gpio_info info; struct gpio_desc *desc; char propname[32]; int i; /* Try first from _DSD */ for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) { if (con_id) { snprintf(propname, sizeof(propname), "%s-%s", con_id, gpio_suffixes[i]); } else { snprintf(propname, sizeof(propname), "%s", gpio_suffixes[i]); } desc = acpi_get_gpiod_by_index(adev, propname, idx, &info); if (!IS_ERR(desc)) break; if (PTR_ERR(desc) == -EPROBE_DEFER) return ERR_CAST(desc); } /* Then from plain _CRS GPIOs */ if (IS_ERR(desc)) { if (!acpi_can_fallback_to_crs(adev, con_id)) return ERR_PTR(-ENOENT); desc = acpi_get_gpiod_by_index(adev, NULL, idx, &info); if (IS_ERR(desc)) return desc; } if (info.gpioint && (*dflags == GPIOD_OUT_LOW || *dflags == GPIOD_OUT_HIGH)) { dev_dbg(dev, "refusing GpioInt() entry when doing GPIOD_OUT_* lookup\n"); return ERR_PTR(-ENOENT); } if (info.polarity == GPIO_ACTIVE_LOW) *lookupflags |= GPIO_ACTIVE_LOW; acpi_gpio_update_gpiod_flags(dflags, &info); return desc; } /** * acpi_node_get_gpiod() - get a GPIO descriptor from ACPI resources * @fwnode: pointer to an ACPI firmware node to get the GPIO information from * @propname: Property name of the GPIO * @index: index of GpioIo/GpioInt resource (starting from %0) * @info: info pointer to fill in (optional) * * If @fwnode is an ACPI device object, call %acpi_get_gpiod_by_index() for it. * Otherwise (ie. it is a data-only non-device object), use the property-based * GPIO lookup to get to the GPIO resource with the relevant information and use * that to obtain the GPIO descriptor to return. */ struct gpio_desc *acpi_node_get_gpiod(struct fwnode_handle *fwnode, const char *propname, int index, struct acpi_gpio_info *info) { struct acpi_gpio_lookup lookup; struct acpi_device *adev; int ret; adev = to_acpi_device_node(fwnode); if (adev) return acpi_get_gpiod_by_index(adev, propname, index, info); if (!is_acpi_data_node(fwnode)) return ERR_PTR(-ENODEV); if (!propname) return ERR_PTR(-EINVAL); memset(&lookup, 0, sizeof(lookup)); lookup.index = index; ret = acpi_gpio_property_lookup(fwnode, propname, index, &lookup); if (ret) return ERR_PTR(ret); ret = acpi_gpio_resource_lookup(&lookup, info); return ret ? ERR_PTR(ret) : lookup.desc; } /** * acpi_dev_gpio_irq_get() - Find GpioInt and translate it to Linux IRQ number * @adev: pointer to a ACPI device to get IRQ from * @index: index of GpioInt resource (starting from %0) * * If the device has one or more GpioInt resources, this function can be * used to translate from the GPIO offset in the resource to the Linux IRQ * number. * * The function is idempotent, though each time it runs it will configure GPIO * pin direction according to the flags in GpioInt resource. * * Return: Linux IRQ number (> %0) on success, negative errno on failure. */ int acpi_dev_gpio_irq_get(struct acpi_device *adev, int index) { int idx, i; unsigned int irq_flags; int ret; for (i = 0, idx = 0; idx <= index; i++) { struct acpi_gpio_info info; struct gpio_desc *desc; desc = acpi_get_gpiod_by_index(adev, NULL, i, &info); /* Ignore -EPROBE_DEFER, it only matters if idx matches */ if (IS_ERR(desc) && PTR_ERR(desc) != -EPROBE_DEFER) return PTR_ERR(desc); if (info.gpioint && idx++ == index) { char label[32]; int irq; if (IS_ERR(desc)) return PTR_ERR(desc); irq = gpiod_to_irq(desc); if (irq < 0) return irq; snprintf(label, sizeof(label), "GpioInt() %d", index); ret = gpiod_configure_flags(desc, label, 0, info.flags); if (ret < 0) return ret; irq_flags = acpi_dev_get_irq_type(info.triggering, info.polarity); /* Set type if specified and different than the current one */ if (irq_flags != IRQ_TYPE_NONE && irq_flags != irq_get_trigger_type(irq)) irq_set_irq_type(irq, irq_flags); return irq; } } return -ENOENT; } EXPORT_SYMBOL_GPL(acpi_dev_gpio_irq_get); static acpi_status acpi_gpio_adr_space_handler(u32 function, acpi_physical_address address, u32 bits, u64 *value, void *handler_context, void *region_context) { struct acpi_gpio_chip *achip = region_context; struct gpio_chip *chip = achip->chip; struct acpi_resource_gpio *agpio; struct acpi_resource *ares; int pin_index = (int)address; acpi_status status; int length; int i; status = acpi_buffer_to_resource(achip->conn_info.connection, achip->conn_info.length, &ares); if (ACPI_FAILURE(status)) return status; if (WARN_ON(ares->type != ACPI_RESOURCE_TYPE_GPIO)) { ACPI_FREE(ares); return AE_BAD_PARAMETER; } agpio = &ares->data.gpio; if (WARN_ON(agpio->io_restriction == ACPI_IO_RESTRICT_INPUT && function == ACPI_WRITE)) { ACPI_FREE(ares); return AE_BAD_PARAMETER; } length = min(agpio->pin_table_length, (u16)(pin_index + bits)); for (i = pin_index; i < length; ++i) { int pin = agpio->pin_table[i]; struct acpi_gpio_connection *conn; struct gpio_desc *desc; bool found; mutex_lock(&achip->conn_lock); found = false; list_for_each_entry(conn, &achip->conns, node) { if (conn->pin == pin) { found = true; desc = conn->desc; break; } } /* * The same GPIO can be shared between operation region and * event but only if the access here is ACPI_READ. In that * case we "borrow" the event GPIO instead. */ if (!found && agpio->shareable == ACPI_SHARED && function == ACPI_READ) { struct acpi_gpio_event *event; list_for_each_entry(event, &achip->events, node) { if (event->pin == pin) { desc = event->desc; found = true; break; } } } if (!found) { enum gpiod_flags flags = acpi_gpio_to_gpiod_flags(agpio); const char *label = "ACPI:OpRegion"; desc = gpiochip_request_own_desc(chip, pin, label, flags); if (IS_ERR(desc)) { status = AE_ERROR; mutex_unlock(&achip->conn_lock); goto out; } conn = kzalloc(sizeof(*conn), GFP_KERNEL); if (!conn) { status = AE_NO_MEMORY; gpiochip_free_own_desc(desc); mutex_unlock(&achip->conn_lock); goto out; } conn->pin = pin; conn->desc = desc; list_add_tail(&conn->node, &achip->conns); } mutex_unlock(&achip->conn_lock); if (function == ACPI_WRITE) gpiod_set_raw_value_cansleep(desc, !!((1 << i) & *value)); else *value |= (u64)gpiod_get_raw_value_cansleep(desc) << i; } out: ACPI_FREE(ares); return status; } static void acpi_gpiochip_request_regions(struct acpi_gpio_chip *achip) { struct gpio_chip *chip = achip->chip; acpi_handle handle = ACPI_HANDLE(chip->parent); acpi_status status; INIT_LIST_HEAD(&achip->conns); mutex_init(&achip->conn_lock); status = acpi_install_address_space_handler(handle, ACPI_ADR_SPACE_GPIO, acpi_gpio_adr_space_handler, NULL, achip); if (ACPI_FAILURE(status)) dev_err(chip->parent, "Failed to install GPIO OpRegion handler\n"); } static void acpi_gpiochip_free_regions(struct acpi_gpio_chip *achip) { struct gpio_chip *chip = achip->chip; acpi_handle handle = ACPI_HANDLE(chip->parent); struct acpi_gpio_connection *conn, *tmp; acpi_status status; status = acpi_remove_address_space_handler(handle, ACPI_ADR_SPACE_GPIO, acpi_gpio_adr_space_handler); if (ACPI_FAILURE(status)) { dev_err(chip->parent, "Failed to remove GPIO OpRegion handler\n"); return; } list_for_each_entry_safe_reverse(conn, tmp, &achip->conns, node) { gpiochip_free_own_desc(conn->desc); list_del(&conn->node); kfree(conn); } } static struct gpio_desc *acpi_gpiochip_parse_own_gpio( struct acpi_gpio_chip *achip, struct fwnode_handle *fwnode, const char **name, unsigned int *lflags, unsigned int *dflags) { struct gpio_chip *chip = achip->chip; struct gpio_desc *desc; u32 gpios[2]; int ret; *lflags = 0; *dflags = 0; *name = NULL; ret = fwnode_property_read_u32_array(fwnode, "gpios", gpios, ARRAY_SIZE(gpios)); if (ret < 0) return ERR_PTR(ret); desc = gpiochip_get_desc(chip, gpios[0]); if (IS_ERR(desc)) return desc; if (gpios[1]) *lflags |= GPIO_ACTIVE_LOW; if (fwnode_property_present(fwnode, "input")) *dflags |= GPIOD_IN; else if (fwnode_property_present(fwnode, "output-low")) *dflags |= GPIOD_OUT_LOW; else if (fwnode_property_present(fwnode, "output-high")) *dflags |= GPIOD_OUT_HIGH; else return ERR_PTR(-EINVAL); fwnode_property_read_string(fwnode, "line-name", name); return desc; } static void acpi_gpiochip_scan_gpios(struct acpi_gpio_chip *achip) { struct gpio_chip *chip = achip->chip; struct fwnode_handle *fwnode; device_for_each_child_node(chip->parent, fwnode) { unsigned int lflags, dflags; struct gpio_desc *desc; const char *name; int ret; if (!fwnode_property_present(fwnode, "gpio-hog")) continue; desc = acpi_gpiochip_parse_own_gpio(achip, fwnode, &name, &lflags, &dflags); if (IS_ERR(desc)) continue; ret = gpiod_hog(desc, name, lflags, dflags); if (ret) { dev_err(chip->parent, "Failed to hog GPIO\n"); fwnode_handle_put(fwnode); return; } } } void acpi_gpiochip_add(struct gpio_chip *chip) { struct acpi_gpio_chip *acpi_gpio; acpi_handle handle; acpi_status status; if (!chip || !chip->parent) return; handle = ACPI_HANDLE(chip->parent); if (!handle) return; acpi_gpio = kzalloc(sizeof(*acpi_gpio), GFP_KERNEL); if (!acpi_gpio) { dev_err(chip->parent, "Failed to allocate memory for ACPI GPIO chip\n"); return; } acpi_gpio->chip = chip; INIT_LIST_HEAD(&acpi_gpio->events); INIT_LIST_HEAD(&acpi_gpio->deferred_req_irqs_list_entry); status = acpi_attach_data(handle, acpi_gpio_chip_dh, acpi_gpio); if (ACPI_FAILURE(status)) { dev_err(chip->parent, "Failed to attach ACPI GPIO chip\n"); kfree(acpi_gpio); return; } if (!chip->names) devprop_gpiochip_set_names(chip, dev_fwnode(chip->parent)); acpi_gpiochip_request_regions(acpi_gpio); acpi_gpiochip_scan_gpios(acpi_gpio); acpi_walk_dep_device_list(handle); } void acpi_gpiochip_remove(struct gpio_chip *chip) { struct acpi_gpio_chip *acpi_gpio; acpi_handle handle; acpi_status status; if (!chip || !chip->parent) return; handle = ACPI_HANDLE(chip->parent); if (!handle) return; status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio); if (ACPI_FAILURE(status)) { dev_warn(chip->parent, "Failed to retrieve ACPI GPIO chip\n"); return; } acpi_gpiochip_free_regions(acpi_gpio); acpi_detach_data(handle, acpi_gpio_chip_dh); kfree(acpi_gpio); } static int acpi_gpio_package_count(const union acpi_object *obj) { const union acpi_object *element = obj->package.elements; const union acpi_object *end = element + obj->package.count; unsigned int count = 0; while (element < end) { switch (element->type) { case ACPI_TYPE_LOCAL_REFERENCE: element += 3; /* Fallthrough */ case ACPI_TYPE_INTEGER: element++; count++; break; default: return -EPROTO; } } return count; } static int acpi_find_gpio_count(struct acpi_resource *ares, void *data) { unsigned int *count = data; if (ares->type == ACPI_RESOURCE_TYPE_GPIO) *count += ares->data.gpio.pin_table_length; return 1; } /** * acpi_gpio_count - return the number of GPIOs associated with a * device / function or -ENOENT if no GPIO has been * assigned to the requested function. * @dev: GPIO consumer, can be NULL for system-global GPIOs * @con_id: function within the GPIO consumer */ int acpi_gpio_count(struct device *dev, const char *con_id) { struct acpi_device *adev = ACPI_COMPANION(dev); const union acpi_object *obj; const struct acpi_gpio_mapping *gm; int count = -ENOENT; int ret; char propname[32]; unsigned int i; /* Try first from _DSD */ for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) { if (con_id) snprintf(propname, sizeof(propname), "%s-%s", con_id, gpio_suffixes[i]); else snprintf(propname, sizeof(propname), "%s", gpio_suffixes[i]); ret = acpi_dev_get_property(adev, propname, ACPI_TYPE_ANY, &obj); if (ret == 0) { if (obj->type == ACPI_TYPE_LOCAL_REFERENCE) count = 1; else if (obj->type == ACPI_TYPE_PACKAGE) count = acpi_gpio_package_count(obj); } else if (adev->driver_gpios) { for (gm = adev->driver_gpios; gm->name; gm++) if (strcmp(propname, gm->name) == 0) { count = gm->size; break; } } if (count > 0) break; } /* Then from plain _CRS GPIOs */ if (count < 0) { struct list_head resource_list; unsigned int crs_count = 0; if (!acpi_can_fallback_to_crs(adev, con_id)) return count; INIT_LIST_HEAD(&resource_list); acpi_dev_get_resources(adev, &resource_list, acpi_find_gpio_count, &crs_count); acpi_dev_free_resource_list(&resource_list); if (crs_count > 0) count = crs_count; } return count ? count : -ENOENT; } bool acpi_can_fallback_to_crs(struct acpi_device *adev, const char *con_id) { /* Never allow fallback if the device has properties */ if (acpi_dev_has_props(adev) || adev->driver_gpios) return false; return con_id == NULL; } /* Run deferred acpi_gpiochip_request_irqs() */ static int acpi_gpio_handle_deferred_request_irqs(void) { struct acpi_gpio_chip *acpi_gpio, *tmp; mutex_lock(&acpi_gpio_deferred_req_irqs_lock); list_for_each_entry_safe(acpi_gpio, tmp, &acpi_gpio_deferred_req_irqs_list, deferred_req_irqs_list_entry) acpi_gpiochip_request_irqs(acpi_gpio); acpi_gpio_deferred_req_irqs_done = true; mutex_unlock(&acpi_gpio_deferred_req_irqs_lock); return 0; } /* We must use _sync so that this runs after the first deferred_probe run */ late_initcall_sync(acpi_gpio_handle_deferred_request_irqs);