[PATCH] gpio: palmas: Fix misreported GPIO out value

From: Andrew Chew
Date: Fri Jul 26 2013 - 15:59:34 EST


It seems that the value read back from the PALMAS_GPIO_DATA_IN register
isn't valid if the GPIO direction is out. When that's the case, we can
read back the PALMAS_GPIO_DATA_OUT register to get the proper output value.

Change-Id: Iaf877e538cfdb37a6759c45ec3c6e4ee31078709
Signed-off-by: Andrew Chew <achew@xxxxxxxxxx>
---
drivers/gpio/gpio-palmas.c | 17 +++++++++++++++--
1 file changed, 15 insertions(+), 2 deletions(-)

diff --git a/drivers/gpio/gpio-palmas.c b/drivers/gpio/gpio-palmas.c
index e3a4e56..7606a85 100644
--- a/drivers/gpio/gpio-palmas.c
+++ b/drivers/gpio/gpio-palmas.c
@@ -43,9 +43,22 @@ static int palmas_gpio_get(struct gpio_chip *gc, unsigned offset)
unsigned int val;
int ret;

- ret = palmas_read(palmas, PALMAS_GPIO_BASE, PALMAS_GPIO_DATA_IN, &val);
+ ret = palmas_read(palmas, PALMAS_GPIO_BASE, PALMAS_GPIO_DATA_DIR, &val);
if (ret < 0) {
- dev_err(gc->dev, "GPIO_DATA_IN read failed, err = %d\n", ret);
+ dev_err(gc->dev, "GPIO_DATA_DIR read failed, err = %d\n", ret);
+ return ret;
+ }
+
+ if (test_bit(offset, &val)) {
+ ret = palmas_read(palmas, PALMAS_GPIO_BASE,
+ PALMAS_GPIO_DATA_OUT, &val);
+ } else {
+ ret = palmas_read(palmas, PALMAS_GPIO_BASE,
+ PALMAS_GPIO_DATA_IN, &val);
+ }
+ if (ret < 0) {
+ dev_err(gc->dev, "GPIO_DATA_IN/OUT read failed, err = %d\n",
+ ret);
return ret;
}
return !!(val & BIT(offset));
--
1.8.1.5

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