94c0308279
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>
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