diff options
| author | Javier Martinez Canillas <javier.martinez@collabora.co.uk> | 2012-12-20 04:56:59 -0800 |
|---|---|---|
| committer | Bryan Wu <cooloney@gmail.com> | 2013-01-02 17:58:41 -0800 |
| commit | 2d7c22f67d5c342a6296127af4f224208449b779 (patch) | |
| tree | e8ddaa212a4833bbb8c4ccf91a73167192955a5a | |
| parent | a49f0d1ea3ec94fc7cf33a7c36a16343b74bd565 (diff) | |
leds: leds-gpio: set devm_gpio_request_one() flags param correctly
commit a99d76f 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: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Reported-by: Arnaud Patard <arnaud.patard@rtp-net.org>
Tested-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
| -rw-r--r-- | drivers/leds/leds-gpio.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/drivers/leds/leds-gpio.c b/drivers/leds/leds-gpio.c index 1885a26776b1..a0d931bcb37c 100644 --- a/drivers/leds/leds-gpio.c +++ b/drivers/leds/leds-gpio.c @@ -127,8 +127,9 @@ static int create_gpio_led(const struct gpio_led *template, led_dat->cdev.flags |= LED_CORE_SUSPENDRESUME; ret = devm_gpio_request_one(parent, template->gpio, - GPIOF_DIR_OUT | (led_dat->active_low ^ state), - template->name); + (led_dat->active_low ^ state) ? + GPIOF_OUT_INIT_HIGH : GPIOF_OUT_INIT_LOW, + template->name); if (ret < 0) return ret; |