diff options
Diffstat (limited to 'drivers/gpio')
| -rw-r--r-- | drivers/gpio/gpiolib-acpi.c | 140 |
1 files changed, 120 insertions, 20 deletions
diff --git a/drivers/gpio/gpiolib-acpi.c b/drivers/gpio/gpiolib-acpi.c index a063eb04b6c..89336c4f82c 100644 --- a/drivers/gpio/gpiolib-acpi.c +++ b/drivers/gpio/gpiolib-acpi.c @@ -17,6 +17,13 @@ #include <linux/acpi.h> #include <linux/interrupt.h> +struct acpi_gpio_evt_pin { + struct list_head node; + acpi_handle *evt_handle; + unsigned int pin; + unsigned int irq; +}; + static int acpi_gpiochip_find(struct gpio_chip *gc, void *data) { if (!gc->dev) @@ -54,7 +61,6 @@ int acpi_get_gpio(char *path, int pin) } EXPORT_SYMBOL_GPL(acpi_get_gpio); - static irqreturn_t acpi_gpio_irq_handler(int irq, void *data) { acpi_handle handle = data; @@ -64,6 +70,27 @@ static irqreturn_t acpi_gpio_irq_handler(int irq, void *data) return IRQ_HANDLED; } +static irqreturn_t acpi_gpio_irq_handler_evt(int irq, void *data) +{ + struct acpi_gpio_evt_pin *evt_pin = data; + struct acpi_object_list args; + union acpi_object arg; + + arg.type = ACPI_TYPE_INTEGER; + arg.integer.value = evt_pin->pin; + args.count = 1; + args.pointer = &arg; + + acpi_evaluate_object(evt_pin->evt_handle, NULL, &args, NULL); + + return IRQ_HANDLED; +} + +static void acpi_gpio_evt_dh(acpi_handle handle, void *data) +{ + /* The address of this function is used as a key. */ +} + /** * acpi_gpiochip_request_interrupts() - Register isr for gpio chip ACPI events * @chip: gpio chip @@ -73,15 +100,13 @@ static irqreturn_t acpi_gpio_irq_handler(int irq, void *data) * 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. - * - * Interrupts are automatically freed on driver detach */ - void acpi_gpiochip_request_interrupts(struct gpio_chip *chip) { struct acpi_buffer buf = {ACPI_ALLOCATE_BUFFER, NULL}; struct acpi_resource *res; - acpi_handle handle, ev_handle; + acpi_handle handle, evt_handle; + struct list_head *evt_pins = NULL; acpi_status status; unsigned int pin; int irq, ret; @@ -98,13 +123,30 @@ void acpi_gpiochip_request_interrupts(struct gpio_chip *chip) if (ACPI_FAILURE(status)) return; - /* If a gpio interrupt has an acpi event handler method, then - * set up an interrupt handler that calls the acpi event handler - */ + status = acpi_get_handle(handle, "_EVT", &evt_handle); + if (ACPI_SUCCESS(status)) { + evt_pins = kzalloc(sizeof(*evt_pins), GFP_KERNEL); + if (evt_pins) { + INIT_LIST_HEAD(evt_pins); + status = acpi_attach_data(handle, acpi_gpio_evt_dh, + evt_pins); + if (ACPI_FAILURE(status)) { + kfree(evt_pins); + evt_pins = NULL; + } + } + } + /* + * If a GPIO interrupt has an ACPI event handler method, or _EVT is + * present, set up an interrupt handler that calls the ACPI event + * handler. + */ for (res = buf.pointer; res && (res->type != ACPI_RESOURCE_TYPE_END_TAG); res = ACPI_NEXT_RESOURCE(res)) { + irq_handler_t handler = NULL; + void *data; if (res->type != ACPI_RESOURCE_TYPE_GPIO || res->data.gpio.connection_type != @@ -115,23 +157,42 @@ void acpi_gpiochip_request_interrupts(struct gpio_chip *chip) if (pin > chip->ngpio) continue; - sprintf(ev_name, "_%c%02X", - res->data.gpio.triggering ? 'E' : 'L', pin); - - status = acpi_get_handle(handle, ev_name, &ev_handle); - if (ACPI_FAILURE(status)) - continue; - irq = chip->to_irq(chip, pin); if (irq < 0) continue; + if (pin <= 255) { + acpi_handle ev_handle; + + sprintf(ev_name, "_%c%02X", + res->data.gpio.triggering ? 'E' : 'L', pin); + status = acpi_get_handle(handle, ev_name, &ev_handle); + if (ACPI_SUCCESS(status)) { + handler = acpi_gpio_irq_handler; + data = ev_handle; + } + } + if (!handler && evt_pins) { + struct acpi_gpio_evt_pin *evt_pin; + + evt_pin = kzalloc(sizeof(*evt_pin), GFP_KERNEL); + if (!evt_pin) + continue; + + list_add_tail(&evt_pin->node, evt_pins); + evt_pin->evt_handle = evt_handle; + evt_pin->pin = pin; + evt_pin->irq = irq; + handler = acpi_gpio_irq_handler_evt; + data = evt_pin; + } + if (!handler) + continue; + /* Assume BIOS sets the triggering, so no flags */ - ret = devm_request_threaded_irq(chip->dev, irq, NULL, - acpi_gpio_irq_handler, - 0, - "GPIO-signaled-ACPI-event", - ev_handle); + ret = devm_request_threaded_irq(chip->dev, irq, NULL, handler, + 0, "GPIO-signaled-ACPI-event", + data); if (ret) dev_err(chip->dev, "Failed to request IRQ %d ACPI event handler\n", @@ -139,3 +200,42 @@ void acpi_gpiochip_request_interrupts(struct gpio_chip *chip) } } EXPORT_SYMBOL(acpi_gpiochip_request_interrupts); + + +/** + * acpi_gpiochip_free_interrupts() - Free GPIO _EVT ACPI event interrupts. + * @chip: gpio chip + * + * Free interrupts associated with the _EVT method for the given GPIO chip. + * + * The remaining ACPI event interrupts associated with the chip are freed + * automatically. + */ +void acpi_gpiochip_free_interrupts(struct gpio_chip *chip) +{ + acpi_handle handle; + acpi_status status; + struct list_head *evt_pins; + struct acpi_gpio_evt_pin *evt_pin, *ep; + + if (!chip->dev || !chip->to_irq) + return; + + handle = ACPI_HANDLE(chip->dev); + if (!handle) + return; + + status = acpi_get_data(handle, acpi_gpio_evt_dh, (void **)&evt_pins); + if (ACPI_FAILURE(status)) + return; + + list_for_each_entry_safe_reverse(evt_pin, ep, evt_pins, node) { + devm_free_irq(chip->dev, evt_pin->irq, evt_pin); + list_del(&evt_pin->node); + kfree(evt_pin); + } + + acpi_detach_data(handle, acpi_gpio_evt_dh); + kfree(evt_pins); +} +EXPORT_SYMBOL(acpi_gpiochip_free_interrupts); |