diff options
Diffstat (limited to 'drivers/gpio/mpc8xxx_gpio.c')
| -rw-r--r-- | drivers/gpio/mpc8xxx_gpio.c | 12 |
1 files changed, 11 insertions, 1 deletions
diff --git a/drivers/gpio/mpc8xxx_gpio.c b/drivers/gpio/mpc8xxx_gpio.c index e9bd38f162c..709d04017d1 100644 --- a/drivers/gpio/mpc8xxx_gpio.c +++ b/drivers/gpio/mpc8xxx_gpio.c @@ -204,7 +204,17 @@ static int mpc8xxx_gpio_plat_to_priv(struct udevice *dev) return -ENOMEM; priv->gpio_count = plat->ngpios; - priv->dat_shadow = 0; + + /* + * On platforms that do support reading back output values, we want to + * try preserving them, so that we don't accidentally set unrelated + * GPIOs to zero in mpc8xxx_gpio_set_value. + */ + if (priv->little_endian) + priv->dat_shadow = in_le32(&priv->base->gpdat) & in_le32(&priv->base->gpdir); + else + priv->dat_shadow = in_be32(&priv->base->gpdat) & in_be32(&priv->base->gpdir); + priv->type = driver_data; |