The bgpio_get_set() call should return a value clamped to [0,1], the current code will return a negative value if reading bit 31, which turns the value negative as this is a signed value and thus gets interpreted as an error by the gpiolib core. Found on the gpio-mxc but applies to any MMIO driver.
Fixes: b19e7f51a55f "gpio: gpio-generic: add flag to read out output value from reg_set" Cc: [email protected] Cc: Vladimir Zapolskiy <[email protected]> Reported-by: Clemens Gruber <[email protected]> Signed-off-by: Linus Walleij <[email protected]> --- drivers/gpio/gpio-generic.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/gpio/gpio-generic.c b/drivers/gpio/gpio-generic.c index 72088028d7a9..ea581dc23d44 100644 --- a/drivers/gpio/gpio-generic.c +++ b/drivers/gpio/gpio-generic.c @@ -141,9 +141,9 @@ static int bgpio_get_set(struct gpio_chip *gc, unsigned int gpio) unsigned long pinmask = bgc->pin2mask(bgc, gpio); if (bgc->dir & pinmask) - return bgc->read_reg(bgc->reg_set) & pinmask; + return !!(bgc->read_reg(bgc->reg_set) & pinmask); else - return bgc->read_reg(bgc->reg_dat) & pinmask; + return !!(bgc->read_reg(bgc->reg_dat) & pinmask); } static int bgpio_get(struct gpio_chip *gc, unsigned int gpio) -- 2.4.3 -- 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
