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mxc_gpio: Correct the GPIO handling in gpio_direction_output()

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Setting the direction and an output value should be done by

First, set the desired output value.

Then, switch to output.

If this is done in the inverse order, like at the moment,
there can be a glitch on the GPIO line while switching first
the old output value and aftwards the new one.

Fix this by inverting the order of the direction/set_value
calls.

Signed-off-by: Dirk Behme <dirk.behme@de.bosch.com>
Acked-by: Stefano Babic <sbabic@denx.de>
This commit is contained in:
Dirk Behme 2013-07-15 15:58:27 +02:00 committed by Stefano Babic
parent 5434caf5ba
commit 04c79cbd5f
1 changed files with 2 additions and 2 deletions
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4
drivers/gpio/mxc_gpio.c
View File

@ -143,10 +143,10 @@ int gpio_direction_input(unsigned gpio)
int gpio_direction_output(unsigned gpio, int value)
{
int ret = mxc_gpio_direction(gpio, MXC_GPIO_DIRECTION_OUT);
int ret = gpio_set_value(gpio, value);
if (ret < 0)
return ret;
return gpio_set_value(gpio, value);
return mxc_gpio_direction(gpio, MXC_GPIO_DIRECTION_OUT);
}