diff options
Diffstat (limited to 'drivers/gpio/gpiolib-acpi.c')
| -rw-r--r-- | drivers/gpio/gpiolib-acpi.c | 51 |
1 files changed, 51 insertions, 0 deletions
diff --git a/drivers/gpio/gpiolib-acpi.c b/drivers/gpio/gpiolib-acpi.c index 5b4111e4be3f..411525ac4cc4 100644 --- a/drivers/gpio/gpiolib-acpi.c +++ b/drivers/gpio/gpiolib-acpi.c @@ -128,6 +128,34 @@ static struct gpio_desc *acpi_get_gpiod(char *path, int pin) return gpiochip_get_desc(chip, pin); } +/** + * acpi_get_and_request_gpiod - Translate ACPI GPIO pin to GPIO descriptor and + * hold a refcount to the GPIO device. + * @path: ACPI GPIO controller full path name, (e.g. "\\_SB.GPO1") + * @pin: ACPI GPIO pin number (0-based, controller-relative) + * @label: Label to pass to gpiod_request() + * + * This function is a simple pass-through to acpi_get_gpiod(), except that + * as it is intended for use outside of the GPIO layer (in a similar fashion to + * gpiod_get_index() for example) it also holds a reference to the GPIO device. + */ +struct gpio_desc *acpi_get_and_request_gpiod(char *path, int pin, char *label) +{ + struct gpio_desc *gpio; + int ret; + + gpio = acpi_get_gpiod(path, pin); + if (IS_ERR(gpio)) + return gpio; + + ret = gpiod_request(gpio, label); + if (ret) + return ERR_PTR(ret); + + return gpio; +} +EXPORT_SYMBOL_GPL(acpi_get_and_request_gpiod); + static irqreturn_t acpi_gpio_irq_handler(int irq, void *data) { struct acpi_gpio_event *event = data; @@ -168,6 +196,29 @@ bool acpi_gpio_get_irq_resource(struct acpi_resource *ares, } 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 + */ +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) { |