device-tree: at91: irq and gpios: problem while requesting a gpio used as an interrupt source.

On 11:35 Mon 13 Jan     , boris brezillon wrote:

On 13/01/2014 11:29, Jean-Jacques Hiblot wrote:

quoted

Hello Nicolas, Jean-Christophe,

As I was trying to enable the touchscreen on the at91sam9261ek with
device-tree support, I ran into an issue. The touchscreen driver needs
to know the state of the pendown gpio and also needs it as an
interrupt source.

The problem is that when a gpio is used as an interrupt, it's
requested by the pinctrl driver during the xlate stage, marking it
unavaliable for the other driver.
It looks like the at91 pinctrl driver is the only one to use
gpio_request() in the xlate stage. Maybe we should remove this:

You should only request it as a GPIO and then use gpio_to_irq to get the
related IRQ.

This here a HUGE issue in the hole kernel

You should NEVER known ti's a gpio in the driver at all gpio_to_irq should never
exist you need to only see the irq

Because what is done here, is to solve the case where only the irq
is request, and in this specific case we need to request the pin as a
GPIO.

this need to be handled at irq level not drivers

Best Regards,
J.