Only the GPIO driver knows about the full GPIO device tree binding used by a device. Add a method to allow the driver to provide this information to the uclass, including the GPIO offset within the device and flags such as the polarity.
Signed-off-by: Simon Glass sjg@chromium.org ---
drivers/gpio/gpio-uclass.c | 16 ++++++++++++++++ include/asm-generic/gpio.h | 29 +++++++++++++++++++++++++++++ 2 files changed, 45 insertions(+)
diff --git a/drivers/gpio/gpio-uclass.c b/drivers/gpio/gpio-uclass.c index 2f3c36b..0a4d9e4 100644 --- a/drivers/gpio/gpio-uclass.c +++ b/drivers/gpio/gpio-uclass.c @@ -7,6 +7,7 @@ #include <common.h> #include <dm.h> #include <errno.h> +#include <fdtdec.h> #include <malloc.h> #include <asm/gpio.h> #include <linux/ctype.h> @@ -91,6 +92,21 @@ int gpio_lookup_name(const char *name, struct udevice **devp, return 0; }
+int gpio_find_and_xlate(struct gpio_desc *desc, + struct fdtdec_phandle_args *args) +{ + struct dm_gpio_ops *ops = gpio_get_ops(desc->dev); + + /* Use the first argument as the offset by default */ + if (args->args_count > 0) + desc->offset = args->args[0]; + else + desc->offset = -1; + desc->flags = 0; + + return ops->xlate ? ops->xlate(desc->dev, desc, args) : 0; +} + static int dm_gpio_request(struct gpio_desc *desc, const char *label) { struct udevice *dev = desc->dev; diff --git a/include/asm-generic/gpio.h b/include/asm-generic/gpio.h index a827a56..c08c963 100644 --- a/include/asm-generic/gpio.h +++ b/include/asm-generic/gpio.h @@ -171,6 +171,8 @@ int gpio_get_raw_function(struct udevice *dev, int offset, const char **namep); int gpio_requestf(unsigned gpio, const char *fmt, ...) __attribute__ ((format (__printf__, 2, 3)));
+struct fdtdec_phandle_args; + /** * struct struct dm_gpio_ops - Driver model GPIO operations * @@ -214,6 +216,33 @@ struct dm_gpio_ops { * @return current function - GPIOF_... */ int (*get_function)(struct udevice *dev, unsigned offset); + + /** + * xlate() - Translate phandle arguments into a GPIO description + * + * This function should set up the fields in desc according to the + * information in the arguments. The uclass will have set up: + * + * @desc->dev to @dev + * @desc->flags to 0 + * @desc->offset to the value of the first argument in args, if any, + * otherwise -1 (which is invalid) + * + * This method is optional so if the above defaults suit it can be + * omitted. Typical behaviour is to set up the GPIOD_ACTIVE_LOW flag + * in desc->flags. + * + * Note that @dev is passed in as a parameter to follow driver model + * uclass conventions, even though it is already available as + * desc->dev. + * + * @dev: GPIO device + * @desc: Place to put GPIO description + * @args: Arguments provided in descripion + * @return 0 if OK, -ve on error + */ + int (*xlate)(struct udevice *dev, struct gpio_desc *desc, + struct fdtdec_phandle_args *args); };
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