This functions adds a way to initialize a GPIO without hogging it. Signed-off-by: Markus Pargmann <mpa@xxxxxxxxxxxxxx> --- drivers/gpio/gpiolib-of.c | 13 ++++++++----- drivers/gpio/gpiolib.c | 24 ++++++++++++++++++++++++ drivers/gpio/gpiolib.h | 2 ++ 3 files changed, 34 insertions(+), 5 deletions(-) diff --git a/drivers/gpio/gpiolib-of.c b/drivers/gpio/gpiolib-of.c index 5fe34a9df3e6..48cdc22eabf2 100644 --- a/drivers/gpio/gpiolib-of.c +++ b/drivers/gpio/gpiolib-of.c @@ -211,15 +211,18 @@ static void of_gpiochip_scan_gpios(struct gpio_chip *chip) enum gpiod_flags dflags; for_each_child_of_node(chip->of_node, np) { - if (!of_property_read_bool(np, "gpio-hog")) - continue; desc = of_parse_own_gpio(np, &name, &lflags, &dflags); - if (IS_ERR(desc)) + if (IS_ERR(desc) || !dflags) continue; - if (gpiod_hog(desc, name, lflags, dflags)) - continue; + if (of_property_read_bool(np, "gpio-hog")) + gpiod_hog(desc, name, lflags, dflags); + else if (of_property_read_bool(np, "gpio-initval")) + gpiod_initialize(desc, lflags, dflags); + else + dev_dbg(chip->dev, "GPIO line %d (%s): neither gpio-hog nor gpio-initval found.\n", + desc_to_gpio(desc), np->name); } } diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index a18f00fc1bb8..3b35f2fafeb2 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -2329,6 +2329,30 @@ static void gpiochip_free_hogs(struct gpio_chip *chip) } /** + * gpiod_initialize - Initialize a GPIO with a given value + * @desc: gpio whose value will be assigned + * @lflags: gpio_lookup_flags - returned from of_find_gpio() or + * of_get_gpio_hog() + * @dflags: gpiod_flags - optional GPIO initialization flags + * + * This is used to initialize GPIOs that were defined in DT + */ +int gpiod_initialize(struct gpio_desc *desc, unsigned long lflags, + enum gpiod_flags dflags) +{ + int status; + + status = gpiod_configure_flags(desc, NULL, dflags); + if (status < 0) { + pr_err("initial setup of GPIO (chip %s, offset %d) failed\n", + gpiod_to_chip(desc)->label, gpio_chip_hwgpio(desc)); + return status; + } + + return 0; +} + +/** * gpiod_get_array - obtain multiple GPIOs from a multi-index GPIO function * @dev: GPIO consumer, can be NULL for system-global GPIOs * @con_id: function within the GPIO consumer diff --git a/drivers/gpio/gpiolib.h b/drivers/gpio/gpiolib.h index 98ab08c0aa2d..4abf53a5e651 100644 --- a/drivers/gpio/gpiolib.h +++ b/drivers/gpio/gpiolib.h @@ -107,6 +107,8 @@ int gpiod_request(struct gpio_desc *desc, const char *label); void gpiod_free(struct gpio_desc *desc); int gpiod_hog(struct gpio_desc *desc, const char *name, unsigned long lflags, enum gpiod_flags dflags); +int gpiod_initialize(struct gpio_desc *desc, unsigned long lflags, + enum gpiod_flags dflags); /* * Return the GPIO number of the passed descriptor relative to its chip -- 2.6.2 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html