From: Roland Stigge Date: Wed, 27 Jun 2012 22:32:14 +0000 (+0200) Subject: gpio: of_get_named_gpio_flags() return -EPROBE_DEFER if GPIO not yet available X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=4fbb0022cba37eef4a263183fdb7dbee89b299f2;p=GitHub%2Fexynos8895%2Fandroid_kernel_samsung_universal8895.git gpio: of_get_named_gpio_flags() return -EPROBE_DEFER if GPIO not yet available of_get_named_gpio_flags() and of_get_named_gpio() return -EPROBE_DEFER if the respective GPIO is not (yet) available. This is useful if driver's probe() functions try to get a GPIO whose controller isn't probed yet. Thus, the driver can be probed again later on. The function still returns -EINVAL on other errors (parse error or node doesn't exist). This way, the case of an optional/intentionally missing GPIO is handled appropriately. Signed-off-by: Roland Stigge Acked-by: Alexandre Pereira da Silva Signed-off-by: Linus Walleij --- diff --git a/drivers/gpio/gpiolib-of.c b/drivers/gpio/gpiolib-of.c index a71aecac451f..a18c4aa68b1e 100644 --- a/drivers/gpio/gpiolib-of.c +++ b/drivers/gpio/gpiolib-of.c @@ -62,7 +62,10 @@ static int of_gpiochip_find_and_xlate(struct gpio_chip *gc, void *data) int of_get_named_gpio_flags(struct device_node *np, const char *propname, int index, enum of_gpio_flags *flags) { - struct gg_data gg_data = { .flags = flags, .out_gpio = -ENODEV }; + /* Return -EPROBE_DEFER to support probe() functions to be called + * later when the GPIO actually becomes available + */ + struct gg_data gg_data = { .flags = flags, .out_gpio = -EPROBE_DEFER }; int ret; /* .of_xlate might decide to not fill in the flags, so clear it. */