Re: [PATCH v2] pinctrl: intel: Initialize GPIO properly when used through irqchip

From: Linus Walleij
Date: Sat Dec 02 2017 - 07:11:39 EST


On Wed, Nov 29, 2017 at 2:25 PM, Mika Westerberg
<mika.westerberg@xxxxxxxxxxxxxxx> wrote:

> When a GPIO is requested using gpiod_get_* APIs the intel pinctrl driver
> switches the pin to GPIO mode and makes sure interrupts are routed to
> the GPIO hardware instead of IOAPIC. However, if the GPIO is used
> directly through irqchip, as is the case with many I2C-HID devices where
> I2C core automatically configures interrupt for the device, the pin is
> not initialized as GPIO. Instead we rely that the BIOS configures the
> pin accordingly which seems not to be the case at least in Asus X540NA
> SKU3 with Focaltech touchpad.
>
> When the pin is not properly configured it might result weird behaviour
> like interrupts suddenly stop firing completely and the touchpad stops
> responding to user input.
>
> Fix this by properly initializing the pin to GPIO mode also when it is
> used directly through irqchip.
>
> Fixes: 7981c0015af2 ("pinctrl: intel: Add Intel Sunrisepoint pin controller and GPIO support")
> Reported-by: Daniel Drake <drake@xxxxxxxxxxxx>
> Reported-and-tested-by: Chris Chiu <chiu@xxxxxxxxxxxx>
> Signed-off-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>
> Cc: stable@xxxxxxxxxxxxxxx
> ---
> Changes from v1:
>
> * Renamed __intel_gpio_init_gpio() to intel_gpio_set_gpio_mode()
> * Added Fixes: and Cc stable@xxxxxxxxxxxxxxx
> * Added Tested-by from Chris Chiu

Patch applied.

Yours,
Linus Walleij