Re: [PATCH] pinctrl: intel: remap the pin number to gpio offset for irq enabled pin

From: Mika Westerberg
Date: Mon Aug 19 2019 - 03:14:18 EST


On Fri, Aug 16, 2019 at 05:38:38PM +0800, Chris Chiu wrote:
> On Asus X571GT, GPIO 297 is configured as an interrupt and serves
> for the touchpad. The touchpad will report input events much less
> than expected after S3 suspend/resume, which results in extremely
> slow cursor movement. However, the number of interrupts observed
> from /proc/interrupts increases much more than expected even no
> touching touchpad.
>
> This is due to the value of PADCFG0 of PIN 225 for the interrupt
> has been changed from 0x80800102 to 0x80100102. The GPIROUTIOXAPIC
> is toggled on which results in the spurious interrupts. The PADCFG0
> of PIN 225 is expected to be saved during suspend, but the 297 is
> saved instead because the gpiochip_line_is_irq() expect the GPIO
> offset but what's really passed to it is PIN number. In this case,
> the /sys/kernel/debug/pinctrl/INT3450:00/gpio-ranges shows
>
> 288: INT3450:00 GPIOS [436 - 459] PINS [216 - 239]
>
> So gpiochip_line_is_irq() returns true for GPIO offset 297, the
> suspend routine spuriously saves the content for PIN 297 which
> we expect to save for PIN 225.

Nice work nailing the issue!

> This commit maps the PIN number to GPIO offset first in the
> intel_pinctrl_should_save() to make sure the values for the
> specific PINs can be correctly saved and then restored.
>
> Signed-off-by: Chris Chiu <chiu@xxxxxxxxxxxx>

Acked-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>

I think this should also have:

Fixes: c538b9436751 ("pinctrl: intel: Only restore pins that are used by the driver")