[RESEND PATCH] leds: leds-gpio: set devm_gpio_request_one() flags correctly

From: Javier Martinez Canillas
Date: Fri Dec 21 2012 - 10:08:03 EST

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);
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@xxxxxxxxxxxxxxx>

This makes LEDs to work again on my IGEPv2 board (TI OMAP3 based SoC).

I sent this patch before but then realized that I only cc'ed to linux-leds.
So, I'm resending the patch cc'ing linux-omap,linux-arm-kernel and LKML to
reach a broader audience and have more people review/test the patch.

Sorry for the noise if someone got it twice.

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 1885a26..a0d931b 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) ?
+ template->name);
if (ret < 0)
return ret;


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