difos/target/linux/bcm27xx/patches-6.12/950-0012-drm-Check-whether-the-gamma-lut-has-changed-before-u.patch
Álvaro Fernández Rojas 8f9e91ad03 bcm27xx: add 6.12 patches from RPi repo
These patches were generated from:
https://github.com/raspberrypi/linux/commits/rpi-6.12.y
With the following command:
git format-patch -N v6.12.27..HEAD
(HEAD -> 8d3206ee456a5ecdf9ddbfd8e5e231e4f0cd716e)

Exceptions:
- (def)configs patches
- github workflows patches
- applied & reverted patches
- readme patches
- wireless patches

Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
2025-05-21 11:32:18 +02:00

29 lines
1.3 KiB
Diff

From 4958d8b2d00b411e7f1a6ab6f3ef222b5ebec2bc Mon Sep 17 00:00:00 2001
From: Dave Stevenson <dave.stevenson@raspberrypi.com>
Date: Tue, 2 Nov 2021 16:01:36 +0000
Subject: [PATCH] drm: Check whether the gamma lut has changed before updating
drm_crtc_legacy_gamma_set updates the gamma_lut blob unconditionally,
which leads to unnecessary reprogramming of hardware.
Check whether the blob contents has actually changed before
signalling that it has been updated.
Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
---
drivers/gpu/drm/drm_color_mgmt.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
--- a/drivers/gpu/drm/drm_color_mgmt.c
+++ b/drivers/gpu/drm/drm_color_mgmt.c
@@ -330,7 +330,9 @@ static int drm_crtc_legacy_gamma_set(str
replaced = drm_property_replace_blob(&crtc_state->degamma_lut,
use_gamma_lut ? NULL : blob);
replaced |= drm_property_replace_blob(&crtc_state->ctm, NULL);
- replaced |= drm_property_replace_blob(&crtc_state->gamma_lut,
+ if (!crtc_state->gamma_lut || !crtc_state->gamma_lut->data ||
+ memcmp(crtc_state->gamma_lut->data, blob_data, blob->length))
+ replaced |= drm_property_replace_blob(&crtc_state->gamma_lut,
use_gamma_lut ? blob : NULL);
crtc_state->color_mgmt_changed |= replaced;