Revert "pinctrl: intel: Initialize GPIO properly when used through irqchip"
authorGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 26 Apr 2018 15:28:00 +0000 (17:28 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Sun, 29 Apr 2018 09:33:09 +0000 (11:33 +0200)
commit94c0308279ec7d550a675140e73262cf0732b70a
tree0281e62c640ab81144b84be1041187e5456e2e25
parent753be7e83bb80128b4a2aa24214c98466905827c
Revert "pinctrl: intel: Initialize GPIO properly when used through irqchip"

This reverts commit f5a26acf0162477af6ee4c11b4fb9cffe5d3e257

Mike writes:
It seems that commit f5a26acf0162 ("pinctrl: intel: Initialize GPIO
properly when used through irqchip") can cause problems on some Skylake
systems with Sunrisepoint PCH-H. Namely on certain systems it may turn
the backlight PWM pin from native mode to GPIO which makes the screen
blank during boot.

There is more information here:

  https://bugzilla.redhat.com/show_bug.cgi?id=1543769

The actual reason is that GPIO numbering used in BIOS is using "Windows"
numbers meaning that they don't match the hardware 1:1 and because of
this a wrong pin (backlight PWM) is picked and switched to GPIO mode.

There is a proper fix for this but since it has quite many dependencies
on commits that cannot be considered stable material, I suggest we
revert commit f5a26acf0162 from stable trees 4.9, 4.14 and 4.15 to
prevent the backlight issue.

Reported-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Fixes: f5a26acf0162 ("pinctrl: intel: Initialize GPIO properly when used through irqchip")
Cc: Daniel Drake <drake@endlessm.com>
Cc: Chris Chiu <chiu@endlessm.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/pinctrl/intel/pinctrl-intel.c