[PATCH] drm/radeon: Restore LCD backlight level on resume (>= R5xx)

[Michel Dänzer]

From: Michel Dänzer <michel.daen...@amd.com>

Instead of only enabling the backlight (which seems to set it to max
brightness), just re-set the current backlight level, which also takes
care of enabling the backlight if necessary.

Only the radeon_atom_encoder_dpms_dig part tested on a Kaveri laptop,
the radeon_atom_encoder_dpms_avivo part is only compile tested.

Cc: stable at vger.kernel.org
Signed-off-by: Michel Dänzer <michel.daenzer at amd.com>
---
 drivers/gpu/drm/radeon/atombios_encoders.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/radeon/atombios_encoders.c 
b/drivers/gpu/drm/radeon/atombios_encoders.c
index c387259..65adb9c 100644
--- a/drivers/gpu/drm/radeon/atombios_encoders.c
+++ b/drivers/gpu/drm/radeon/atombios_encoders.c
@@ -1624,8 +1624,9 @@ radeon_atom_encoder_dpms_avivo(struct drm_encoder 
*encoder, int mode)
                } else
                        atom_execute_table(rdev->mode_info.atom_context, index, 
(uint32_t *)&args);
                if (radeon_encoder->devices & (ATOM_DEVICE_LCD_SUPPORT)) {
-                       args.ucAction = ATOM_LCD_BLON;
-                       atom_execute_table(rdev->mode_info.atom_context, index, 
(uint32_t *)&args);
+                       struct radeon_encoder_atom_dig *dig = 
radeon_encoder->enc_priv;
+
+                       atombios_set_backlight_level(radeon_encoder, 
dig->backlight_level);
                }
                break;
        case DRM_MODE_DPMS_STANDBY:
@@ -1706,8 +1707,7 @@ radeon_atom_encoder_dpms_dig(struct drm_encoder *encoder, 
int mode)
                                atombios_dig_encoder_setup(encoder, 
ATOM_ENCODER_CMD_DP_VIDEO_ON, 0);
                }
                if (radeon_encoder->devices & (ATOM_DEVICE_LCD_SUPPORT))
-                       atombios_dig_transmitter_setup(encoder,
-                                                      
ATOM_TRANSMITTER_ACTION_LCD_BLON, 0, 0);
+                       atombios_set_backlight_level(radeon_encoder, 
dig->backlight_level);
                if (ext_encoder)
                        atombios_external_encoder_setup(encoder, ext_encoder, 
ATOM_ENABLE);
                break;
-- 
2.5.0