commit a59b3c80fd0041223ccf720504974a543b81b1d0
author Alex Deucher <alexander.deucher@amd.com> Thu Mar 08 09:56:01 2018 -0500
committer Alex Deucher <alexander.deucher@amd.com> Wed Mar 14 15:08:40 2018 -0500
tree a882f3883661b92385cc0d1365c4ba6f9497754f
parent 0660b58c9038f5ef94b8fe33716449945ea786e5

drm/amdgpu: save/restore backlight level in legacy dce code

Save/restore the backlight level scratch register in S3/S4 so the
backlight level comes back at the previously requested level.

Bug: https://bugzilla.kernel.org/show_bug.cgi?id=199047
Fixes: 4ec6ecf48c64d (drm/amdgpu: drop scratch regs save and restore from S3/S4 handling)
Acked-by: Michel Dänzer <michel.daenzer@amd.com>
Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/amdgpu_mode.h

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_mode.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_mode.h
index d9533bb..588cf65 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_mode.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_mode.h
@@ -350,6 +350,7 @@ struct amdgpu_mode_info {
 	u16 firmware_flags;
 	/* pointer to backlight encoder */
 	struct amdgpu_encoder *bl_encoder;
+	u8 bl_level; /* saved backlight level */
 	struct amdgpu_audio	audio; /* audio stuff */
 	int			num_crtc; /* number of crtcs */
 	int			num_hpd; /* number of hpd pins */