Jani Nikula 425faacff2 drm/i915/backlight: fix CPU mode backlight takeover on LPT ... [ Upstream commit bb83d5fb55 ] The pch_get_backlight(), lpt_get_backlight(), and lpt_set_backlight() functions operate directly on the hardware registers. If inverting the value is needed, using intel_panel_compute_brightness(), it should only be done in the interface between hardware registers and panel->backlight.level. The CPU mode takeover code added in commit 5b1ec9ac7a ("drm/i915/backlight: Fix backlight takeover on LPT, v3.") reads the hardware register and converts to panel->backlight.level correctly, however the value written back should remain in the hardware register "domain". This hasn't been an issue, because GM45 machines are the only known users of i915.invert_brightness and the brightness invert quirk, and without one of them no conversion is made. It's likely nobody's ever hit the problem. Fixes: 5b1ec9ac7a ("drm/i915/backlight: Fix backlight takeover on LPT, v3.") Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Cc: Lyude Paul <lyude@redhat.com> Cc: <stable@vger.kernel.org> # v5.1+ Reviewed-by: Lyude Paul <lyude@redhat.com> Signed-off-by: Jani Nikula <jani.nikula@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20210108152841.6944-1-jani.nikula@intel.com (cherry picked from commit 0d4ced1c5b) Signed-off-by: Jani Nikula <jani.nikula@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org>		2021-01-19 18:26:13 +01:00
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drm	drm/i915/backlight: fix CPU mode backlight takeover on LPT	2021-01-19 18:26:13 +01:00
host1x	gpu: host1x: debug: Fix multiple channels emitting messages simultaneously	2020-08-19 08:16:04 +02:00
ipu-v3	gpu: ipu-v3: image-convert: Wait for all EOFs before completing a tile	2020-08-21 13:05:32 +02:00
vga	topic/remove-fbcon-notifiers:	2019-06-26 12:26:34 +02:00
Makefile	treewide: Add SPDX license identifier - Makefile/Kconfig	2019-05-21 10:50:46 +02:00