diff options
| author | Axel Lin <axel.lin@ingics.com> | 2014-04-08 07:59:39 +0800 |
|---|---|---|
| committer | Linus Walleij <linus.walleij@linaro.org> | 2014-04-28 12:35:09 -0700 |
| commit | ef7de2625fdd40c2d26a10bf87cc1626017adc18 (patch) | |
| tree | bcd0e10d8a9c19879cddf3907cd699768f1fa591 /drivers/gpio/gpio-zevio.c | |
| parent | e45d1c80c0eee88e82751461e9cac49d9ed287bc (diff) | |
| download | linux-ef7de2625fdd40c2d26a10bf87cc1626017adc18.tar.bz2 | |
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>
Diffstat (limited to 'drivers/gpio/gpio-zevio.c')
| -rw-r--r-- | drivers/gpio/gpio-zevio.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/drivers/gpio/gpio-zevio.c b/drivers/gpio/gpio-zevio.c index 7184f4577848..6270f755d0ed 100644 --- 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; } |