[3.19.y-ckt stable] Patch "drm/radeon: fix dpms when driver backlight control is disabled" has been added to staging queue

[Kamal Mostafa]

This is a note to let you know that I have just added a patch titled

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

to the linux-3.19.y-queue branch of the 3.19.y-ckt extended stable tree 
which can be found at:

    http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.19.y-queue

This patch is scheduled to be released in version 3.19.8-ckt10.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.19.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

------

>From 3da62041042ef45ded050abe197a9200609ae7fd Mon Sep 17 00:00:00 2001
From: Alex Deucher <alexander.deucher at 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

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 at amd.com>
Signed-off-by: Alex Deucher <alexander.deucher at amd.com>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 drivers/gpu/drm/radeon/atombios_encoders.c | 18 ++++++++++++++----
 1 file changed, 14 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/radeon/atombios_encoders.c b/drivers/gpu/drm/radeon/atombios_encoders.c
index d538ebb..1cceeb1 100644
--- a/drivers/gpu/drm/radeon/atombios_encoders.c
+++ b/drivers/gpu/drm/radeon/atombios_encoders.c
@@ -1587,9 +1587,14 @@ 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)) {
-			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:
@@ -1669,8 +1674,13 @@ radeon_atom_encoder_dpms_dig(struct drm_encoder *encoder, int mode)
 			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;
--
1.9.1