Mario Limonciello c7f6e836e6 drm/amd/display: Restore guard against default backlight value < 1 nit
commit b96ab339ee upstream.

Mark reports that brightness is not restored after Xorg dpms screen blank.

This behavior was introduced by commit d9e865826c ("drm/amd/display:
Simplify brightness initialization") which dropped the cached backlight
value in display code, but also removed code for when the default value
read back was less than 1 nit.

Restore this code so that the backlight brightness is restored to the
correct default value in this circumstance.

Reported-by: Mark Herbert <mark.herbert42@gmail.com>
Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/3031
Cc: stable@vger.kernel.org
Cc: Camille Cho <camille.cho@amd.com>
Cc: Krunoslav Kovac <krunoslav.kovac@amd.com>
Cc: Hamza Mahfooz <hamza.mahfooz@amd.com>
Fixes: d9e865826c ("drm/amd/display: Simplify brightness initialization")
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-12-20 17:02:04 +01:00
2023-10-19 16:40:00 +02:00
2023-12-13 18:45:36 +01:00

Linux kernel
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There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
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