gpio: zevio: Get correct gpio output value

Read gpio output value from ZEVIO_GPIO_OUTPUT.
The spin_lock is required to ensure the direction is not changed before reading
input/ouput value.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

diff --git a/drivers/gpio/gpio-zevio.c b/drivers/gpio/gpio-zevio.c
index 7184f45..6270f75 100644 (file)
--- a/drivers/gpio/gpio-zevio.c
+++ b/drivers/gpio/gpio-zevio.c
@@ -81,9 +81,15 @@ static inline void zevio_gpio_port_set(struct zevio_gpio *c, unsigned pin,
 static int zevio_gpio_get(struct gpio_chip *chip, unsigned pin)
 {
        struct zevio_gpio *controller = to_zevio_gpio(chip);
+       u32 val, dir;
 
-       /* Only reading allowed, so no spinlock needed */
-       u32 val = zevio_gpio_port_get(controller, pin, ZEVIO_GPIO_INPUT);
+       spin_lock(&controller->lock);
+       dir = zevio_gpio_port_get(controller, pin, ZEVIO_GPIO_DIRECTION);
+       if (dir & BIT(ZEVIO_GPIO_BIT(pin)))
+               val = zevio_gpio_port_get(controller, pin, ZEVIO_GPIO_INPUT);
+       else
+               val = zevio_gpio_port_get(controller, pin, ZEVIO_GPIO_OUTPUT);
+       spin_unlock(&controller->lock);
 
        return (val >> ZEVIO_GPIO_BIT(pin)) & 0x1;
 }