[PATCH u-boot v2019.04-aspeed-openbmc 1/6] gpio: Add gpio_request_by_line_name()

[Eddie James]

On 1/30/22 19:25, Andrew Jeffery wrote:
> 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


Reviewed-by: Eddie James <eajames at linux.ibm.com>


>
> Signed-off-by: Andrew Jeffery <andrew at aj.id.au>
> ---
>   drivers/gpio/gpio-uclass.c | 26 ++++++++++++++++++++++++++
>   include/asm-generic/gpio.h | 19 +++++++++++++++++++
>   2 files changed, 45 insertions(+)
>
> diff --git a/drivers/gpio/gpio-uclass.c b/drivers/gpio/gpio-uclass.c
> index 219caa651bb2..425bbc5cb880 100644
> --- a/drivers/gpio/gpio-uclass.c
> +++ b/drivers/gpio/gpio-uclass.c
> @@ -878,6 +878,32 @@ int gpio_request_by_name(struct udevice *dev, const char *list_name, int index,
>   				 index, desc, flags, index > 0, NULL);
>   }
>   
> +int gpio_request_by_line_name(struct udevice *dev, const char *line_name,
> +			      struct gpio_desc *desc, int flags)
> +{
> +	int ret;
> +
> +	ret = dev_read_stringlist_search(dev, "gpio-line-names", line_name);
> +	if (ret < 0)
> +		return ret;
> +
> +	desc->dev = dev;
> +	desc->offset = ret;
> +	desc->flags = 0;
> +
> +	ret = dm_gpio_request(desc, line_name);
> +	if (ret) {
> +		debug("%s: dm_gpio_requestf failed\n", __func__);
> +		return ret;
> +	}
> +
> +	ret = dm_gpio_set_dir_flags(desc, flags | desc->flags);
> +	if (ret)
> +		debug("%s: dm_gpio_set_dir failed\n", __func__);
> +
> +	return ret;
> +}
> +
>   int gpio_request_list_by_name_nodev(ofnode node, const char *list_name,
>   				    struct gpio_desc *desc, int max_count,
>   				    int flags)
> diff --git a/include/asm-generic/gpio.h b/include/asm-generic/gpio.h
> index d6cf18744fda..6ed0ba11b6c1 100644
> --- a/include/asm-generic/gpio.h
> +++ b/include/asm-generic/gpio.h
> @@ -451,6 +451,25 @@ 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
>    *