FAILED: patch "[PATCH] drm/amd/display: Update color props when modeset is required" failed to apply to 4.16-stable tree

[<gregkh@linuxfoundation.org>]

The patch below does not apply to the 4.16-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

>From bc13f2f88eae63af943ab967cb14bb602f8f2eeb Mon Sep 17 00:00:00 2001
From: "Leo (Sunpeng) Li" <sunpeng.li@amd.com>
Date: Thu, 31 May 2018 10:23:37 -0400
Subject: [PATCH] drm/amd/display: Update color props when modeset is required

This fixes issues where color management properties don't persist
over DPMS on/off, or when the CRTC is moved across connectors.

Signed-off-by: Leo (Sunpeng) Li <sunpeng.li@amd.com>
Reviewed-by: Harry Wentland <Harry.Wentland@amd.com>
Cc: stable@vger.kernel.org
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index 1a7e96ee6051..27579443cdc5 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -4717,8 +4717,12 @@ static int dm_update_crtcs_state(struct dc *dc,
 			update_stream_scaling_settings(
 				&new_crtc_state->mode, dm_new_conn_state, dm_new_crtc_state->stream);
 
-		/* Color managment settings */
-		if (dm_new_crtc_state->base.color_mgmt_changed) {
+		/*
+		 * Color management settings. We also update color properties
+		 * when a modeset is needed, to ensure it gets reprogrammed.
+		 */
+		if (dm_new_crtc_state->base.color_mgmt_changed ||
+		    drm_atomic_crtc_needs_modeset(new_crtc_state)) {
 			ret = amdgpu_dm_set_regamma_lut(dm_new_crtc_state);
 			if (ret)
 				goto fail;