Patch "drm/radeon: fix dpms when driver backlight control is disabled" has been added to the 4.2-stable tree

[<gregkh@linuxfoundation.org>]

This is a note to let you know that I've just added the patch titled

    drm/radeon: fix dpms when driver backlight control is disabled

to the 4.2-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     drm-radeon-fix-dpms-when-driver-backlight-control-is-disabled.patch
and it can be found in the queue-4.2 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From ae93580ee59c02395c1711d3e6b90546b8137b86 Mon Sep 17 00:00:00 2001
From: Alex Deucher <alexander.deucher@amd.com>
Date: Tue, 27 Oct 2015 10:56:44 -0400
Subject: drm/radeon: fix dpms when driver backlight control is disabled
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

From: Alex Deucher <alexander.deucher@amd.com>

commit ae93580ee59c02395c1711d3e6b90546b8137b86 upstream.

If driver backlight control is disabled, either by driver
parameter or default per-asic setting, revert to the old behavior.

Fixes a regression in commit:
4281f46ef839050d2ef60348f661eb463c21cc2e

Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/gpu/drm/radeon/atombios_encoders.c |   18 ++++++++++++++----
 1 file changed, 14 insertions(+), 4 deletions(-)

--- a/drivers/gpu/drm/radeon/atombios_encoders.c
+++ b/drivers/gpu/drm/radeon/atombios_encoders.c
@@ -1624,9 +1624,14 @@ radeon_atom_encoder_dpms_avivo(struct dr
 		} else
 			atom_execute_table(rdev->mode_info.atom_context, index, (uint32_t *)&args);
 		if (radeon_encoder->devices & (ATOM_DEVICE_LCD_SUPPORT)) {
-			struct radeon_encoder_atom_dig *dig = radeon_encoder->enc_priv;
+			if (rdev->mode_info.bl_encoder) {
+				struct radeon_encoder_atom_dig *dig = radeon_encoder->enc_priv;
 
-			atombios_set_backlight_level(radeon_encoder, dig->backlight_level);
+				atombios_set_backlight_level(radeon_encoder, dig->backlight_level);
+			} else {
+				args.ucAction = ATOM_LCD_BLON;
+				atom_execute_table(rdev->mode_info.atom_context, index, (uint32_t *)&args);
+			}
 		}
 		break;
 	case DRM_MODE_DPMS_STANDBY:
@@ -1706,8 +1711,13 @@ radeon_atom_encoder_dpms_dig(struct drm_
 			if (ASIC_IS_DCE4(rdev))
 				atombios_dig_encoder_setup(encoder, ATOM_ENCODER_CMD_DP_VIDEO_ON, 0);
 		}
-		if (radeon_encoder->devices & (ATOM_DEVICE_LCD_SUPPORT))
-			atombios_set_backlight_level(radeon_encoder, dig->backlight_level);
+		if (radeon_encoder->devices & (ATOM_DEVICE_LCD_SUPPORT)) {
+			if (rdev->mode_info.bl_encoder)
+				atombios_set_backlight_level(radeon_encoder, dig->backlight_level);
+			else
+				atombios_dig_transmitter_setup(encoder,
+							       ATOM_TRANSMITTER_ACTION_LCD_BLON, 0, 0);
+		}
 		if (ext_encoder)
 			atombios_external_encoder_setup(encoder, ext_encoder, ATOM_ENABLE);
 		break;


Patches currently in stable-queue which might be from alexander.deucher@amd.com are

queue-4.2/drm-radeon-move-bl-encoder-assignment-into-bl-init.patch
queue-4.2/drm-amdgpu-add-missing-dpm-check-for-kv-dpm-late-init.patch
queue-4.2/drm-radeon-fix-dpms-when-driver-backlight-control-is-disabled.patch
queue-4.2/drm-amdgpu-don-t-try-to-recreate-sysfs-entries-on-resume.patch
queue-4.2/drm-radeon-don-t-try-to-recreate-sysfs-entries-on-resume.patch
queue-4.2/drm-radeon-dpm-don-t-add-pwm-attributes-if-dpm-is-disabled.patch