[PATCH] gpio/at91: free GPIO after configuring as input

[Alexander Stein]

I'm CC'ing some input guys if this can't be solved in the pinctrl/irq side.

On Friday 11 April 2014, 23:30:33 wrote Jean-Christophe PLAGNIOL-VILLARD:
> 
> On Apr 11, 2014, at 10:24 PM, Alexander Stein <alexanders83 at web.de> wrote:
> 
> > 
> > If the GPIO stays requested a device driver can't request it again.
> > e.g. Without this patch the ads7846 driver returns the following error:
> > ads7846 spi32766.3: failed to request/setup pendown GPIO15: -16
> > ads7846: probe of spi32766.3 failed with error -16
> > 
> > /sys/kernel/debug/gpio shows this:
> > GPIOs 0-31, platform/fffff200.gpio, fffff200.gpio:
> > [/ahb/apb/pinctrl at fffff200/gpio at fffff200] GPIOfffff200.gpio15: [gpio] set
> > 
> > Signed-off-by: Alexander Stein <alexanders83 at web.de>
> > ---
> > I'm aware that it makes sense this GPIO is/stays requested, but either the
> > pinctl or device driver have to be adjusted as both can't request this GPIO.
> > I think the latter shouldn't change.
> > 
> > drivers/pinctrl/pinctrl-at91.c | 2 ++
> > 1 file changed, 2 insertions(+)
> > 
> > diff --git a/drivers/pinctrl/pinctrl-at91.c b/drivers/pinctrl/pinctrl-at91.c
> > index d990e33..63176f2 100644
> > --- a/drivers/pinctrl/pinctrl-at91.c
> > +++ b/drivers/pinctrl/pinctrl-at91.c
> > @@ -1493,6 +1493,8 @@ static int at91_gpio_irq_domain_xlate(struct irq_domain *d,
> > 	if (ret)
> > 		return ret;
> > 
> > +	gpio_free(pin);
> > +
> 
> NACK it the whole key point the gpio use as a IRQ so the irq generic code request it
> > 	return 0;
> > }
> > 
>