On Thu, Jul 31, 2014 at 9:07 PM, Mark Brown broonie@kernel.org wrote:
From: Mark Brown broonie@linaro.org
DT based systems should have no reason to use fixed GPIO numbers but some drivers that work on both DT and non-DT platforms specify them anyway. In order to improve robustness in cases where drivers use gpio_is_valid() to check for a valid GPIO on data initialized to zero as a default and avoid bugs due to assuptions about fixed numbers creeping in ignore any specified base when DT is in use.
I agree that DT users should not use the base number at all - but the fact is some of them are doing it. Aren't we going to break some user-space users that will expect to find a GPIO under a given number?
Also, how is this going to help with gpio_is_valid() against zero-initialized data?
Signed-off-by: Mark Brown broonie@linaro.org
drivers/gpio/gpiolib.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index 768f0831db18..11d3cf1cbca7 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -234,7 +234,7 @@ int gpiochip_add(struct gpio_chip *chip)
spin_lock_irqsave(&gpio_lock, flags);
if (base < 0) {
if (base < 0 || of_have_populated_dt()) { base = gpiochip_find_base(chip->ngpio); if (base < 0) { status = base;-- 2.0.1