From 34be6968c3570d8e03fcafcd60c02f315b8f4602 Mon Sep 17 00:00:00 2001 From: Andrew Jeffery Date: Mon, 31 Jan 2022 13:54:05 +1030 Subject: gpio: Add gpio_request_by_line_name() Add support for the upstream gpio-line-names property already described in the common GPIO binding document[1]. The ability to search for a line name allows boards to lift the implementation of common GPIO behaviours away from specific line indexes on a GPIO controller. [1] https://github.com/devicetree-org/dt-schema/blob/3c35bfee83c2e38e2ae7af5f83eb89ca94a521e8/dtschema/schemas/gpio/gpio.yaml#L17 Signed-off-by: Andrew Jeffery --- include/asm-generic/gpio.h | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) (limited to 'include') diff --git a/include/asm-generic/gpio.h b/include/asm-generic/gpio.h index adc19e9765d..81f63f06f15 100644 --- a/include/asm-generic/gpio.h +++ b/include/asm-generic/gpio.h @@ -579,6 +579,25 @@ int gpio_claim_vector(const int *gpio_num_array, const char *fmt); int gpio_request_by_name(struct udevice *dev, const char *list_name, int index, struct gpio_desc *desc, int flags); +/* gpio_request_by_line_name - Locate and request a GPIO by line name + * + * Request a GPIO using the offset of the provided line name in the + * gpio-line-names property found in the OF node of the GPIO udevice. + * + * This allows boards to implement common behaviours using GPIOs while not + * requiring specific GPIO offsets be used. + * + * @dev: An instance of a GPIO controller udevice + * @line_name: The name of the GPIO (e.g. "bmc-secure-boot") + * @desc: A GPIO descriptor that is populated with the requested GPIO + * upon return + * @flags: The GPIO settings apply to the request + * @return 0 if the named line was found and requested successfully, or a + * negative error code if the GPIO cannot be found or the request failed. + */ +int gpio_request_by_line_name(struct udevice *dev, const char *line_name, + struct gpio_desc *desc, int flags); + /** * gpio_request_list_by_name() - Request a list of GPIOs * -- cgit v1.2.3