diff options
Diffstat (limited to 'drivers/gpio/gpiolib-acpi.c')
| -rw-r--r-- | drivers/gpio/gpiolib-acpi.c | 1508 |
1 files changed, 1508 insertions, 0 deletions
diff --git a/drivers/gpio/gpiolib-acpi.c b/drivers/gpio/gpiolib-acpi.c new file mode 100644 index 000000000..44ee319da --- /dev/null +++ b/drivers/gpio/gpiolib-acpi.c @@ -0,0 +1,1508 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * ACPI helpers for GPIO API + * + * Copyright (C) 2012, Intel Corporation + * Authors: Mathias Nyman <mathias.nyman@linux.intel.com> + * Mika Westerberg <mika.westerberg@linux.intel.com> + */ + +#include <linux/dmi.h> +#include <linux/errno.h> +#include <linux/gpio/consumer.h> +#include <linux/gpio/driver.h> +#include <linux/gpio/machine.h> +#include <linux/export.h> +#include <linux/acpi.h> +#include <linux/interrupt.h> +#include <linux/mutex.h> +#include <linux/pinctrl/pinctrl.h> + +#include "gpiolib.h" +#include "gpiolib-acpi.h" + +static int run_edge_events_on_boot = -1; +module_param(run_edge_events_on_boot, int, 0444); +MODULE_PARM_DESC(run_edge_events_on_boot, + "Run edge _AEI event-handlers at boot: 0=no, 1=yes, -1=auto"); + +static char *ignore_wake; +module_param(ignore_wake, charp, 0444); +MODULE_PARM_DESC(ignore_wake, + "controller@pin combos on which to ignore the ACPI wake flag " + "ignore_wake=controller@pin[,controller@pin[,...]]"); + +struct acpi_gpiolib_dmi_quirk { + bool no_edge_events_on_boot; + char *ignore_wake; +}; + +/** + * 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; +}; + +/* + * For GPIO chips 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 GPIO chips + * 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 GPIO chip 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 | IRQF_ONESHOT, "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 */ + if (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 bool acpi_gpio_in_ignore_list(const char *controller_in, int pin_in) +{ + const char *controller, *pin_str; + int len, pin; + char *endp; + + controller = ignore_wake; + while (controller) { + pin_str = strchr(controller, '@'); + if (!pin_str) + goto err; + + len = pin_str - controller; + if (len == strlen(controller_in) && + strncmp(controller, controller_in, len) == 0) { + pin = simple_strtoul(pin_str + 1, &endp, 10); + if (*endp != 0 && *endp != ',') + goto err; + + if (pin == pin_in) + return true; + } + + controller = strchr(controller, ','); + if (controller) + controller++; + } + + return false; +err: + pr_err_once("Error invalid value for gpiolib_acpi.ignore_wake: %s\n", + ignore_wake); + return false; +} + +static bool acpi_gpio_irq_is_wake(struct device *parent, + struct acpi_resource_gpio *agpio) +{ + int pin = agpio->pin_table[0]; + + if (agpio->wake_capable != ACPI_WAKE_CAPABLE) + return false; + + if (acpi_gpio_in_ignore_list(dev_name(parent), pin)) { + dev_info(parent, "Ignoring wakeup on pin %d\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; + 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[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; + + desc = gpiochip_request_own_desc(chip, pin, "ACPI:Event", + GPIO_ACTIVE_HIGH, GPIOD_IN); + 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; + 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); + +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 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) +{ + 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, if it is pulled down we assume default to be low, + * otherwise we leave pin untouched. + */ + switch (agpio->pin_config) { + case ACPI_PIN_CONFIG_PULLUP: + return GPIOD_OUT_HIGH; + case ACPI_PIN_CONFIG_PULLDOWN: + return GPIOD_OUT_LOW; + default: + break; + } + default: + break; + } + + /* + * 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) +{ + 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; +} + +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; +} + +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; + default: + break; + } + + if (info->polarity == GPIO_ACTIVE_LOW) + *lookupflags |= GPIO_ACTIVE_LOW; + + return 0; +} + +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->desc) { + const struct acpi_resource_gpio *agpio = &ares->data.gpio; + bool gpioint = agpio->connection_type == ACPI_RESOURCE_GPIO_TYPE_INT; + struct gpio_desc *desc; + int pin_index; + + if (lookup->info.quirks & ACPI_GPIO_QUIRK_ONLY_GPIOIO && gpioint) + lookup->index++; + + if (lookup->n++ != lookup->index) + return 1; + + pin_index = lookup->pin_index; + if (pin_index >= agpio->pin_table_length) + return 1; + + if (lookup->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; + lookup->info.pin_config = agpio->pin_config; + lookup->info.gpioint = gpioint; + + /* + * 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; +} + +static 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; +} + +struct gpio_desc *acpi_find_gpio(struct device *dev, + const char *con_id, + unsigned int idx, + enum gpiod_flags *dflags, + unsigned long *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); + } + + acpi_gpio_update_gpiod_flags(dflags, &info); + acpi_gpio_update_gpiod_lookup_flags(lookupflags, &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 (i.e. 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. + * + * If the GPIO cannot be translated or there is an error an ERR_PTR is + * returned. + */ +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_by() - Find GpioInt and translate it to Linux IRQ number + * @adev: pointer to a ACPI device to get IRQ from + * @name: optional name of GpioInt resource + * @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. + * + * The function takes optional @name parameter. If the resource has a property + * name, then only those will be taken into account. + * + * Return: Linux IRQ number (> %0) on success, negative errno on failure. + */ +int acpi_dev_gpio_irq_get_by(struct acpi_device *adev, const char *name, 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, name, 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) { + unsigned long lflags = GPIO_LOOKUP_FLAGS_DEFAULT; + 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, lflags, info.flags); + if (ret < 0) + 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); + } + + return irq; + } + + } + return -ENOENT; +} +EXPORT_SYMBOL_GPL(acpi_dev_gpio_irq_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; + 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, + GPIO_ACTIVE_HIGH, + 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 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 = 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 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"); + 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; + } + + 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 - count the GPIOs associated with a device / function + * @dev: GPIO consumer, can be %NULL for system-global GPIOs + * @con_id: function within the GPIO consumer + * + * Return: + * The number of GPIOs associated with a device / function or %-ENOENT, + * if no GPIO has been assigned to the requested function. + */ +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; +} + +/* Run deferred acpi_gpiochip_request_irqs() */ +static int __init 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); + +static const struct dmi_system_id gpiolib_acpi_quirks[] __initconst = { + { + /* + * The Minix Neo Z83-4 has a micro-USB-B id-pin handler for + * a non existing micro-USB-B connector which puts the HDMI + * DDC pins in GPIO mode, breaking HDMI support. + */ + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "MINIX"), + DMI_MATCH(DMI_PRODUCT_NAME, "Z83-4"), + }, + .driver_data = &(struct acpi_gpiolib_dmi_quirk) { + .no_edge_events_on_boot = true, + }, + }, + { + /* + * The Terra Pad 1061 has a micro-USB-B id-pin handler, which + * instead of controlling the actual micro-USB-B turns the 5V + * boost for its USB-A connector off. The actual micro-USB-B + * connector is wired for charging only. + */ + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "Wortmann_AG"), + DMI_MATCH(DMI_PRODUCT_NAME, "TERRA_PAD_1061"), + }, + .driver_data = &(struct acpi_gpiolib_dmi_quirk) { + .no_edge_events_on_boot = true, + }, + }, + { + /* + * The Dell Venue 10 Pro 5055, with Bay Trail SoC + TI PMIC uses an + * external embedded-controller connected via I2C + an ACPI GPIO + * event handler on INT33FFC:02 pin 12, causing spurious wakeups. + */ + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), + DMI_MATCH(DMI_PRODUCT_NAME, "Venue 10 Pro 5055"), + }, + .driver_data = &(struct acpi_gpiolib_dmi_quirk) { + .ignore_wake = "INT33FC:02@12", + }, + }, + { + /* + * HP X2 10 models with Cherry Trail SoC + TI PMIC use an + * external embedded-controller connected via I2C + an ACPI GPIO + * event handler on INT33FF:01 pin 0, causing spurious wakeups. + * When suspending by closing the LID, the power to the USB + * keyboard is turned off, causing INT0002 ACPI events to + * trigger once the XHCI controller notices the keyboard is + * gone. So INT0002 events cause spurious wakeups too. Ignoring + * EC wakes breaks wakeup when opening the lid, the user needs + * to press the power-button to wakeup the system. The + * alternative is suspend simply not working, which is worse. + */ + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "HP"), + DMI_MATCH(DMI_PRODUCT_NAME, "HP x2 Detachable 10-p0XX"), + }, + .driver_data = &(struct acpi_gpiolib_dmi_quirk) { + .ignore_wake = "INT33FF:01@0,INT0002:00@2", + }, + }, + { + /* + * HP X2 10 models with Bay Trail SoC + AXP288 PMIC use an + * external embedded-controller connected via I2C + an ACPI GPIO + * event handler on INT33FC:02 pin 28, causing spurious wakeups. + */ + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"), + DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion x2 Detachable"), + DMI_MATCH(DMI_BOARD_NAME, "815D"), + }, + .driver_data = &(struct acpi_gpiolib_dmi_quirk) { + .ignore_wake = "INT33FC:02@28", + }, + }, + { + /* + * HP X2 10 models with Cherry Trail SoC + AXP288 PMIC use an + * external embedded-controller connected via I2C + an ACPI GPIO + * event handler on INT33FF:01 pin 0, causing spurious wakeups. + */ + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "HP"), + DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion x2 Detachable"), + DMI_MATCH(DMI_BOARD_NAME, "813E"), + }, + .driver_data = &(struct acpi_gpiolib_dmi_quirk) { + .ignore_wake = "INT33FF:01@0", + }, + }, + {} /* Terminating entry */ +}; + +static int __init acpi_gpio_setup_params(void) +{ + const struct acpi_gpiolib_dmi_quirk *quirk = NULL; + const struct dmi_system_id *id; + + id = dmi_first_match(gpiolib_acpi_quirks); + if (id) + quirk = id->driver_data; + + if (run_edge_events_on_boot < 0) { + if (quirk && quirk->no_edge_events_on_boot) + run_edge_events_on_boot = 0; + else + run_edge_events_on_boot = 1; + } + + if (ignore_wake == NULL && quirk && quirk->ignore_wake) + ignore_wake = quirk->ignore_wake; + + return 0; +} + +/* Directly after dmi_setup() which runs as core_initcall() */ +postcore_initcall(acpi_gpio_setup_params); |