// 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 #include #include "gpiolib.h" #include "gpiolib-acpi.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: handler function to pass to request_irq() when requesting the IRQ * @pin: GPIO pin number on the struct gpio_chip * @irq: Linux IRQ number for the event, for request_irq() / 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 * @irq_requested:True if request_irq() has been done * @desc: struct 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; }; /** * struct acpi_gpio_info - ACPI GPIO specific information * @adev: reference to ACPI device which consumes GPIO resource * @flags: GPIO initialization flags * @gpioint: if %true this GPIO is of type GpioInt otherwise type is GpioIo * @wake_capable: wake capability as provided by ACPI * @pin_config: pin bias as provided by ACPI * @polarity: interrupt polarity as provided by ACPI * @triggering: triggering type as provided by ACPI * @debounce: debounce timeout as provided by ACPI * @quirks: Linux specific quirks as provided by struct acpi_gpio_mapping */ struct acpi_gpio_info { struct acpi_device *adev; enum gpiod_flags flags; bool gpioint; bool wake_capable; int pin_config; int polarity; int triggering; unsigned int debounce; unsigned int quirks; }; static int acpi_gpiochip_find(struct gpio_chip *gc, const void *data) { /* First check the actual GPIO device */ if (device_match_acpi_handle(&gc->gpiodev->dev, data)) return true; /* * When the ACPI device is artificially split to the banks of GPIOs, * where each of them is represented by a separate GPIO device, * the firmware node of the physical device may not be shared among * the banks as they may require different values for the same property, * e.g., number of GPIOs in a certain bank. In such case the ACPI handle * of a GPIO device is NULL and can not be used. Hence we have to check * the parent device to be sure that there is no match before bailing * out. */ if (gc->parent) return device_match_acpi_handle(gc->parent, data); return false; } /** * 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) * * Returns: * GPIO descriptor to use with Linux generic GPIO API. * If the GPIO cannot be translated or there is an error an ERR_PTR is * returned. * * Specifically returns %-EPROBE_DEFER if the referenced GPIO * controller does not have GPIO chip registered at the moment. This is to * support probe deferral. */ static struct gpio_desc *acpi_get_gpiod(char *path, unsigned int pin) { acpi_handle handle; acpi_status status; status = acpi_get_handle(NULL, path, &handle); if (ACPI_FAILURE(status)) return ERR_PTR(-ENODEV); struct gpio_device *gdev __free(gpio_device_put) = gpio_device_find(handle, acpi_gpiochip_find); if (!gdev) return ERR_PTR(-EPROBE_DEFER); /* * FIXME: keep track of the reference to the GPIO device somehow * instead of putting it here. */ return gpio_device_get_desc(gdev, 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); /** * acpi_gpio_get_io_resource - Fetch details of an ACPI resource if it is a GPIO * I/O resource or return False if not. * @ares: Pointer to the ACPI resource to fetch * @agpio: Pointer to a &struct acpi_resource_gpio to store the output pointer * * Returns: * %true if GpioIo resource is found, %false otherwise. */ bool acpi_gpio_get_io_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_IO) return false; *agpio = gpio; return true; } EXPORT_SYMBOL_GPL(acpi_gpio_get_io_resource); static void acpi_gpiochip_request_irq(struct acpi_gpio_chip *acpi_gpio, struct acpi_gpio_event *event) { struct device *parent = acpi_gpio->chip->parent; int ret, value; ret = request_threaded_irq(event->irq, NULL, event->handler, event->irqflags | IRQF_ONESHOT, "ACPI:Event", event); if (ret) { dev_err(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 */ if (acpi_gpio_need_run_edge_events_on_boot() && (event->irqflags & (IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING))) { 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 enum gpiod_flags acpi_gpio_to_gpiod_flags(const struct acpi_resource_gpio *agpio, int polarity) { /* GpioInt() implies input configuration */ if (agpio->connection_type == ACPI_RESOURCE_GPIO_TYPE_INT) return GPIOD_IN; 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 * and the polarity instead. If the pin is pulled up we assume * default to be high, if it is pulled down we assume default * to be low, otherwise we leave pin untouched. For active low * polarity values will be switched. See also * Documentation/firmware-guide/acpi/gpio-properties.rst. */ switch (agpio->pin_config) { case ACPI_PIN_CONFIG_PULLUP: return polarity == GPIO_ACTIVE_LOW ? GPIOD_OUT_LOW : GPIOD_OUT_HIGH; case ACPI_PIN_CONFIG_PULLDOWN: return polarity == GPIO_ACTIVE_LOW ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW; default: break; } break; default: break; } /* * Assume that the BIOS has configured the direction and pull * accordingly. */ return GPIOD_ASIS; } static struct gpio_desc *acpi_request_own_gpiod(struct gpio_chip *chip, struct acpi_resource_gpio *agpio, unsigned int index, const char *label) { int polarity = GPIO_ACTIVE_HIGH; enum gpiod_flags flags = acpi_gpio_to_gpiod_flags(agpio, polarity); unsigned int pin = agpio->pin_table[index]; struct gpio_desc *desc; int ret; desc = gpiochip_request_own_desc(chip, pin, label, polarity, flags); if (IS_ERR(desc)) return desc; /* ACPI uses hundredths of milliseconds units */ ret = gpio_set_debounce_timeout(desc, agpio->debounce_timeout * 10); if (ret) dev_warn(chip->parent, "Failed to set debounce-timeout for pin 0x%04X, err %d\n", pin, ret); return desc; } static bool acpi_gpio_irq_is_wake(struct device *parent, const struct acpi_resource_gpio *agpio) { unsigned int pin = agpio->pin_table[0]; if (agpio->wake_capable != ACPI_WAKE_CAPABLE) return false; if (acpi_gpio_in_ignore_list(ACPI_GPIO_IGNORE_WAKE, dev_name(parent), pin)) { dev_info(parent, "Ignoring wakeup on pin %u\n", pin); return false; } return true; } /* Always returns AE_OK so that we keep looping over the resources */ 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; unsigned int pin; int ret, 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[8]; sprintf(ev_name, "_%c%02X", 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; if (acpi_gpio_in_ignore_list(ACPI_GPIO_IGNORE_INTERRUPT, dev_name(chip->parent), pin)) { dev_info(chip->parent, "Ignoring interrupt on pin %u\n", pin); return AE_OK; } desc = acpi_request_own_gpiod(chip, agpio, 0, "ACPI:Event"); if (IS_ERR(desc)) { dev_err(chip->parent, "Failed to request GPIO for pin 0x%04X, err %ld\n", pin, PTR_ERR(desc)); return AE_OK; } ret = gpiochip_lock_as_irq(chip, pin); if (ret) { dev_err(chip->parent, "Failed to lock GPIO pin 0x%04X as interrupt, err %d\n", pin, ret); goto fail_free_desc; } irq = gpiod_to_irq(desc); if (irq < 0) { dev_err(chip->parent, "Failed to translate GPIO pin 0x%04X to IRQ, err %d\n", pin, irq); 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 = acpi_gpio_irq_is_wake(chip->parent, agpio); 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_OK; } /** * 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; 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; if (acpi_quirk_skip_gpio_event_handlers()) return; acpi_walk_resources(handle, METHOD_NAME__AEI, acpi_gpiochip_alloc_event, acpi_gpio); if (acpi_gpio_add_to_deferred_list(&acpi_gpio->deferred_req_irqs_list_entry)) 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; acpi_gpio_remove_from_deferred_list(&acpi_gpio->deferred_req_irqs_list_entry); 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); void __init acpi_gpio_process_deferred_list(struct list_head *list) { struct acpi_gpio_chip *acpi_gpio, *tmp; list_for_each_entry_safe(acpi_gpio, tmp, list, deferred_req_irqs_list_entry) acpi_gpiochip_request_irqs(acpi_gpio); } 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); void acpi_dev_remove_driver_gpios(struct acpi_device *adev) { if (adev) adev->driver_gpios = NULL; } EXPORT_SYMBOL_GPL(acpi_dev_remove_driver_gpios); static void acpi_dev_release_driver_gpios(void *adev) { acpi_dev_remove_driver_gpios(adev); } int devm_acpi_dev_add_driver_gpios(struct device *dev, const struct acpi_gpio_mapping *gpios) { struct acpi_device *adev = ACPI_COMPANION(dev); int ret; ret = acpi_dev_add_driver_gpios(adev, gpios); if (ret) return ret; return devm_add_action_or_reset(dev, acpi_dev_release_driver_gpios, adev); } EXPORT_SYMBOL_GPL(devm_acpi_dev_add_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 || !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 *params = gm->data + index; args->fwnode = acpi_fwnode_handle(adev); args->args[0] = params->crs_entry_index; args->args[1] = params->line_index; args->args[2] = params->active_low; args->nargs = 3; *quirks = gm->quirks; return true; } return false; } static int __acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags, enum gpiod_flags update) { const enum gpiod_flags mask = GPIOD_FLAGS_BIT_DIR_SET | GPIOD_FLAGS_BIT_DIR_OUT | GPIOD_FLAGS_BIT_DIR_VAL; 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 = (*flags & ~mask) | (update & mask); } return ret; } static 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; } static int acpi_gpio_update_gpiod_lookup_flags(unsigned long *lookupflags, struct acpi_gpio_info *info) { switch (info->pin_config) { case ACPI_PIN_CONFIG_PULLUP: *lookupflags |= GPIO_PULL_UP; break; case ACPI_PIN_CONFIG_PULLDOWN: *lookupflags |= GPIO_PULL_DOWN; break; case ACPI_PIN_CONFIG_NOPULL: *lookupflags |= GPIO_PULL_DISABLE; break; default: break; } if (info->polarity == GPIO_ACTIVE_LOW) *lookupflags |= GPIO_ACTIVE_LOW; return 0; } struct acpi_gpio_lookup { struct acpi_gpio_params params; struct acpi_gpio_info *info; struct gpio_desc *desc; int n; }; static int acpi_populate_gpio_lookup(struct acpi_resource *ares, void *data) { struct acpi_gpio_lookup *lookup = data; struct acpi_gpio_params *params = &lookup->params; struct acpi_gpio_info *info = lookup->info; if (ares->type != ACPI_RESOURCE_TYPE_GPIO) return 1; if (!lookup->desc) { const struct acpi_resource_gpio *agpio = &ares->data.gpio; bool gpioint = agpio->connection_type == ACPI_RESOURCE_GPIO_TYPE_INT; struct gpio_desc *desc; u16 pin_index; if (info->quirks & ACPI_GPIO_QUIRK_ONLY_GPIOIO && gpioint) params->crs_entry_index++; if (lookup->n++ != params->crs_entry_index) return 1; pin_index = params->line_index; if (pin_index >= agpio->pin_table_length) return 1; if (info->quirks & ACPI_GPIO_QUIRK_ABSOLUTE_NUMBER) desc = gpio_to_desc(agpio->pin_table[pin_index]); else desc = acpi_get_gpiod(agpio->resource_source.string_ptr, agpio->pin_table[pin_index]); lookup->desc = desc; info->pin_config = agpio->pin_config; info->debounce = agpio->debounce_timeout; info->gpioint = gpioint; info->wake_capable = acpi_gpio_irq_is_wake(&info->adev->dev, agpio); /* * 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 (info->gpioint) { info->polarity = agpio->polarity; info->triggering = agpio->triggering; } else { info->polarity = params->active_low; } info->flags = acpi_gpio_to_gpiod_flags(agpio, info->polarity); } return 1; } static int acpi_gpio_resource_lookup(struct acpi_gpio_lookup *lookup) { struct acpi_gpio_info *info = lookup->info; struct acpi_device *adev = 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; return 0; } static int acpi_gpio_property_lookup(struct fwnode_handle *fwnode, const char *propname, struct acpi_gpio_lookup *lookup) { struct fwnode_reference_args args; struct acpi_gpio_params *params = &lookup->params; struct acpi_gpio_info *info = lookup->info; unsigned int index = params->crs_entry_index; 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; adev = to_acpi_device_node(fwnode); 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; params->crs_entry_index = args.args[0]; params->line_index = args.args[1]; params->active_low = !!args.args[2]; info->adev = to_acpi_device_node(args.fwnode); 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) * @lookup: pointer to struct acpi_gpio_lookup to fill in * * Function goes through ACPI resources for @adev and based on @lookup.index looks * up a GpioIo/GpioInt resource, translates it to the Linux GPIO descriptor, * and returns it. @lookup.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). * * Returns: * 0 on success, negative errno on failure. * * The @lookup is filled with GPIO descriptor to use with Linux generic GPIO API. * If the GPIO cannot be translated an error will be returned. * * Note: if the GPIO resource has multiple entries in the pin list, this * function only returns the first. */ static int acpi_get_gpiod_by_index(struct acpi_device *adev, const char *propname, struct acpi_gpio_lookup *lookup) { struct acpi_gpio_params *params = &lookup->params; struct acpi_gpio_info *info = lookup->info; int ret; if (propname) { dev_dbg(&adev->dev, "GPIO: looking up %s\n", propname); ret = acpi_gpio_property_lookup(acpi_fwnode_handle(adev), propname, lookup); if (ret) return ret; dev_dbg(&adev->dev, "GPIO: _DSD returned %s %u %u %u\n", dev_name(&info->adev->dev), params->crs_entry_index, params->line_index, params->active_low); } else { dev_dbg(&adev->dev, "GPIO: looking up %u in _CRS\n", params->crs_entry_index); info->adev = adev; } return acpi_gpio_resource_lookup(lookup); } /** * acpi_get_gpiod_from_data() - get a GPIO descriptor from ACPI data node * @fwnode: pointer to an ACPI firmware node to get the GPIO information from * @propname: Property name of the GPIO * @lookup: pointer to struct acpi_gpio_lookup to fill in * * This function uses the property-based GPIO lookup to get to the GPIO * resource with the relevant information from a data-only ACPI firmware node * and uses that to obtain the GPIO descriptor to return. * * Returns: * 0 on success, negative errno on failure. * * The @lookup is filled with GPIO descriptor to use with Linux generic GPIO API. * If the GPIO cannot be translated an error will be returned. */ static int acpi_get_gpiod_from_data(struct fwnode_handle *fwnode, const char *propname, struct acpi_gpio_lookup *lookup) { int ret; if (!is_acpi_data_node(fwnode)) return -ENODEV; if (!propname) return -EINVAL; ret = acpi_gpio_property_lookup(fwnode, propname, lookup); if (ret) return ret; return acpi_gpio_resource_lookup(lookup); } static bool acpi_can_fallback_to_crs(struct acpi_device *adev, const char *con_id) { /* If there is no ACPI device, there is no _CRS to fall back to */ if (!adev) return false; /* Never allow fallback if the device has properties */ if (acpi_dev_has_props(adev) || adev->driver_gpios) return false; return con_id == NULL; } static struct gpio_desc * __acpi_find_gpio(struct fwnode_handle *fwnode, const char *con_id, unsigned int idx, bool can_fallback, struct acpi_gpio_info *info) { struct acpi_device *adev = to_acpi_device_node(fwnode); struct acpi_gpio_lookup lookup; struct gpio_desc *desc; char propname[32]; int ret; memset(&lookup, 0, sizeof(lookup)); lookup.params.crs_entry_index = idx; lookup.info = info; /* Try first from _DSD */ for_each_gpio_property_name(propname, con_id) { if (adev) ret = acpi_get_gpiod_by_index(adev, propname, &lookup); else ret = acpi_get_gpiod_from_data(fwnode, propname, &lookup); if (ret) continue; desc = lookup.desc; if (PTR_ERR(desc) == -EPROBE_DEFER) return desc; if (!IS_ERR(desc)) return desc; } /* Then from plain _CRS GPIOs */ if (can_fallback) { ret = acpi_get_gpiod_by_index(adev, NULL, &lookup); if (ret) return ERR_PTR(ret); return lookup.desc; } return ERR_PTR(-ENOENT); } struct gpio_desc *acpi_find_gpio(struct fwnode_handle *fwnode, const char *con_id, unsigned int idx, enum gpiod_flags *dflags, unsigned long *lookupflags) { struct acpi_device *adev = to_acpi_device_node(fwnode); bool can_fallback = acpi_can_fallback_to_crs(adev, con_id); struct acpi_gpio_info info; struct gpio_desc *desc; desc = __acpi_find_gpio(fwnode, con_id, idx, can_fallback, &info); if (IS_ERR(desc)) return desc; if (info.gpioint && (*dflags == GPIOD_OUT_LOW || *dflags == GPIOD_OUT_HIGH)) { dev_dbg(&adev->dev, "refusing GpioInt() entry when doing GPIOD_OUT_* lookup\n"); return ERR_PTR(-ENOENT); } acpi_gpio_update_gpiod_flags(dflags, &info); acpi_gpio_update_gpiod_lookup_flags(lookupflags, &info); return desc; } /** * acpi_dev_gpio_irq_wake_get_by() - Find GpioInt and translate it to Linux IRQ number * @adev: pointer to a ACPI device to get IRQ from * @con_id: optional name of GpioInt resource * @index: index of GpioInt resource (starting from %0) * @wake_capable: Set to true if the IRQ is wake capable * * 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. * * The function takes optional @con_id parameter. If the resource has * a @con_id in a property, then only those will be taken into account. * * The GPIO is considered wake capable if the GpioInt resource specifies * SharedAndWake or ExclusiveAndWake. * * Returns: * Linux IRQ number (> 0) on success, negative errno on failure. */ int acpi_dev_gpio_irq_wake_get_by(struct acpi_device *adev, const char *con_id, int index, bool *wake_capable) { struct fwnode_handle *fwnode = acpi_fwnode_handle(adev); 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; /* Ignore -EPROBE_DEFER, it only matters if idx matches */ desc = __acpi_find_gpio(fwnode, con_id, i, true, &info); if (IS_ERR(desc) && PTR_ERR(desc) != -EPROBE_DEFER) return PTR_ERR(desc); if (info.gpioint && idx++ == index) { unsigned long lflags = GPIO_LOOKUP_FLAGS_DEFAULT; enum gpiod_flags dflags = GPIOD_ASIS; char label[32]; int irq; if (IS_ERR(desc)) return PTR_ERR(desc); irq = gpiod_to_irq(desc); if (irq < 0) return irq; acpi_gpio_update_gpiod_flags(&dflags, &info); acpi_gpio_update_gpiod_lookup_flags(&lflags, &info); snprintf(label, sizeof(label), "%pfwP GpioInt(%d)", fwnode, index); ret = gpiod_set_consumer_name(desc, con_id ?: label); if (ret) return ret; ret = gpiod_configure_flags(desc, label, lflags, dflags); if (ret < 0) return ret; /* ACPI uses hundredths of milliseconds units */ ret = gpio_set_debounce_timeout(desc, info.debounce * 10); if (ret) return ret; irq_flags = acpi_dev_get_irq_type(info.triggering, info.polarity); /* * If the IRQ is not already in use then set type * if specified and different than the current one. */ if (can_request_irq(irq, irq_flags)) { if (irq_flags != IRQ_TYPE_NONE && irq_flags != irq_get_trigger_type(irq)) irq_set_irq_type(irq, irq_flags); } else { dev_dbg(&adev->dev, "IRQ %d already in use\n", irq); } /* avoid suspend issues with GPIOs when systems are using S3 */ if (wake_capable && acpi_gbl_FADT.flags & ACPI_FADT_LOW_POWER_S0) *wake_capable = info.wake_capable; return irq; } } return -ENOENT; } EXPORT_SYMBOL_GPL(acpi_dev_gpio_irq_wake_get_by); 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; u16 pin_index = 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_t(u16, agpio->pin_table_length, pin_index + bits); for (i = pin_index; i < length; ++i) { unsigned 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) { desc = acpi_request_own_gpiod(chip, agpio, i, "ACPI:OpRegion"); if (IS_ERR(desc)) { mutex_unlock(&achip->conn_lock); status = AE_ERROR; goto out; } conn = kzalloc(sizeof(*conn), GFP_KERNEL); if (!conn) { gpiochip_free_own_desc(desc); mutex_unlock(&achip->conn_lock); status = AE_NO_MEMORY; 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, !!(*value & BIT(i))); 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 long *lflags, enum gpiod_flags *dflags) { struct gpio_chip *chip = achip->chip; struct gpio_desc *desc; u32 gpios[2]; int ret; *lflags = GPIO_LOOKUP_FLAGS_DEFAULT; *dflags = GPIOD_ASIS; *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; device_for_each_child_node_scoped(chip->parent, fwnode) { unsigned long lflags; enum gpiod_flags 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"); return; } } } void acpi_gpiochip_add(struct gpio_chip *chip) { struct acpi_gpio_chip *acpi_gpio; struct acpi_device *adev; acpi_status status; if (!chip || !chip->parent) return; adev = ACPI_COMPANION(chip->parent); if (!adev) 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(adev->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; } acpi_gpiochip_request_regions(acpi_gpio); acpi_gpiochip_scan_gpios(acpi_gpio); acpi_dev_clear_dependencies(adev); } 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 - count the GPIOs associated with a firmware node / function * @fwnode: firmware node of the GPIO consumer * @con_id: function within the GPIO consumer * * Returns: * The number of GPIOs associated with a firmware node / function or %-ENOENT, * if no GPIO has been assigned to the requested function. */ int acpi_gpio_count(const struct fwnode_handle *fwnode, const char *con_id) { struct acpi_device *adev = to_acpi_device_node(fwnode); const union acpi_object *obj; const struct acpi_gpio_mapping *gm; int count = -ENOENT; int ret; char propname[32]; /* Try first from _DSD */ for_each_gpio_property_name(propname, con_id) { 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; }