From 108d23e322a247d9f89ba2e2742520ead0944cc9 Mon Sep 17 00:00:00 2001 From: Timur Tabi Date: Thu, 27 Jul 2017 13:19:23 -0500 Subject: [PATCH] gpiolib: request the gpio before querying its direction Before querying a GPIO to determine its direction, the GPIO should be formally requested. This allows the GPIO driver to block access to unavailable GPIOs, which makes it easier for some drivers to support sparse GPIO maps. Signed-off-by: Timur Tabi Signed-off-by: Linus Walleij --- drivers/gpio/gpiolib.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index cd003b7..bd90737 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -1201,6 +1201,14 @@ int gpiochip_add_data(struct gpio_chip *chip, void *data) struct gpio_desc *desc = &gdev->descs[i]; desc->gdev = gdev; + + if (chip->request) { + status = chip->request(chip, i); + if (status < 0) + /* The GPIO is unavailable, so skip it */ + continue; + } + /* * REVISIT: most hardware initializes GPIOs as inputs * (often with pullups enabled) so power usage is @@ -1226,6 +1234,9 @@ int gpiochip_add_data(struct gpio_chip *chip, void *data) */ set_bit(FLAG_IS_OUT, &desc->flags); } + + if (chip->free) + chip->free(chip, i); } #ifdef CONFIG_PINCTRL -- 2.7.4