For MPC8572/MPC8536, the status of GPIOs defined as output cannot be determined by reading GPDAT register, so the code use shadow data register instead. But if the input pins are asserted high, they will always read high due to the shadow data, even if the pins are set to low.
So the input pins should be read directly from GPDAT, not the shadow data. Signed-off-by: Liu Gang <[email protected]> --- drivers/gpio/gpio-mpc8xxx.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/gpio/gpio-mpc8xxx.c b/drivers/gpio/gpio-mpc8xxx.c index 9ae29cc..1d4ac75 100644 --- a/drivers/gpio/gpio-mpc8xxx.c +++ b/drivers/gpio/gpio-mpc8xxx.c @@ -71,6 +71,7 @@ static int mpc8572_gpio_get(struct gpio_chip *gc, unsigned int gpio) struct mpc8xxx_gpio_chip *mpc8xxx_gc = to_mpc8xxx_gpio_chip(mm); val = in_be32(mm->regs + GPIO_DAT) & ~in_be32(mm->regs + GPIO_DIR); + mpc8xxx_gc->data &= in_be32(mm->regs + GPIO_DIR); return (val | mpc8xxx_gc->data) & mpc8xxx_gpio2mask(gpio); } -- 1.8.4.1 -- To unsubscribe from this list: send the line "unsubscribe linux-gpio" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
