[PATCH] gpio: tegra: read output value when gpio is set in direction_out

From: Laxman Dewangan
Date: Thu Nov 08 2012 - 01:29:36 EST


Read the output value when gpio is set for the output mode for
gpio_get_value(). Reading input value in direction out does not
give correct value.

Signed-off-by: Laxman Dewangan <ldewangan@xxxxxxxxxx>
---
drivers/gpio/gpio-tegra.c | 6 ++++++
1 files changed, 6 insertions(+), 0 deletions(-)

diff --git a/drivers/gpio/gpio-tegra.c b/drivers/gpio/gpio-tegra.c
index c7c175a..0fb2ce7 100644
--- a/drivers/gpio/gpio-tegra.c
+++ b/drivers/gpio/gpio-tegra.c
@@ -135,6 +135,12 @@ static void tegra_gpio_set(struct gpio_chip *chip, unsigned offset, int value)

static int tegra_gpio_get(struct gpio_chip *chip, unsigned offset)
{
+ int bit_val = BIT(GPIO_BIT(offset));
+
+ /* If gpio is in output mode then read from the out value */
+ if (tegra_gpio_readl(GPIO_OE(offset)) & bit_val)
+ return !!(tegra_gpio_readl(GPIO_OUT(offset)) & bit_val);
+
return (tegra_gpio_readl(GPIO_IN(offset)) >> GPIO_BIT(offset)) & 0x1;
}

--
1.7.1.1

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