leds: leds-gpio: set devm_gpio_request_one() flags param correctly
commit a99d76f9 leds: leds-gpio: use gpio_request_one changed the leds-gpio driver to use gpio_request_one() instead of gpio_request() + gpio_direction_output() Unfortunately, it also made a semantic change that breaks the leds-gpio driver. The gpio_request_one() flags parameter was set to: GPIOF_DIR_OUT | (led_dat->active_low ^ state) Since GPIOF_DIR_OUT is 0, the final flags value will just be the XOR'ed value of led_dat->active_low and state. This value were used to distinguish between HIGH/LOW output initial level and call gpio_direction_output() accordingly. With this new semantic gpio_request_one() will take the flags value of 1 as a configuration of input direction (GPIOF_DIR_IN) and will call gpio_direction_input() instead of gpio_direction_output(). int gpio_request_one(unsigned gpio, unsigned long flags, const char *label) { .. if (flags & GPIOF_DIR_IN) err = gpio_direction_input(gpio); else err = gpio_direction_output(gpio, (flags & GPIOF_INIT_HIGH) ? 1 : 0); .. } The right semantic is to evaluate led_dat->active_low ^ state and set the output initial level explicitly. Signed-off-by: NJavier Martinez Canillas <javier.martinez@collabora.co.uk> Reported-by: NArnaud Patard <arnaud.patard@rtp-net.org> Tested-by: NEzequiel Garcia <ezequiel.garcia@free-electrons.com> Signed-off-by: NBryan Wu <cooloney@gmail.com>
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