This is a note to let you know that I've just added the patch titled
drm/msm/dp: skip validity check for DP CTS EDID checksum
to the 6.6-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-msm-dp-skip-validity-check-for-dp-cts-edid-check.patch
and it can be found in the queue-6.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 8b7d0d0f98dacbde7390b09fae001dec63ca0519
Author: Jani Nikula <jani.nikula@xxxxxxxxx>
Date: Fri Sep 1 17:20:34 2023 +0300
drm/msm/dp: skip validity check for DP CTS EDID checksum
[ Upstream commit a251c9d8e30833b260101edb9383b176ee2b7cb1 ]
The DP CTS test for EDID last block checksum expects the checksum for
the last block, invalid or not. Skip the validity check.
For the most part (*), the EDIDs returned by drm_get_edid() will be
valid anyway, and there's the CTS workaround to get the checksum for
completely invalid EDIDs. See commit 7948fe12d47a ("drm/msm/dp: return
correct edid checksum after corrupted edid checksum read").
This lets us remove one user of drm_edid_block_valid() with hopes the
function can be removed altogether in the future.
(*) drm_get_edid() ignores checksum errors on CTA extensions.
Cc: Abhinav Kumar <quic_abhinavk@xxxxxxxxxxx>
Cc: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
Cc: Kuogee Hsieh <khsieh@xxxxxxxxxxxxxx>
Cc: Marijn Suijten <marijn.suijten@xxxxxxxxxxxxxx>
Cc: Rob Clark <robdclark@xxxxxxxxx>
Cc: Sean Paul <sean@xxxxxxxxxx>
Cc: Stephen Boyd <swboyd@xxxxxxxxxxxx>
Cc: linux-arm-msm@xxxxxxxxxxxxxxx
Cc: freedreno@xxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Jani Nikula <jani.nikula@xxxxxxxxx>
Reviewed-by: Stephen Boyd <swboyd@xxxxxxxxxxxx>
Reviewed-by: Abhinav Kumar <quic_abhinavk@xxxxxxxxxxx>
Reviewed-by: Kuogee Hsieh <quic_khsieh@xxxxxxxxxxx>
Patchwork: https://patchwork.freedesktop.org/patch/555361/
Link: https://lore.kernel.org/r/20230901142034.580802-1-jani.nikula@xxxxxxxxx
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/gpu/drm/msm/dp/dp_panel.c b/drivers/gpu/drm/msm/dp/dp_panel.c
index 42d52510ffd4a..86a8e06c7a60f 100644
--- a/drivers/gpu/drm/msm/dp/dp_panel.c
+++ b/drivers/gpu/drm/msm/dp/dp_panel.c
@@ -289,26 +289,9 @@ int dp_panel_get_modes(struct dp_panel *dp_panel,
static u8 dp_panel_get_edid_checksum(struct edid *edid)
{
- struct edid *last_block;
- u8 *raw_edid;
- bool is_edid_corrupt = false;
+ edid += edid->extensions;
- if (!edid) {
- DRM_ERROR("invalid edid input\n");
- return 0;
- }
-
- raw_edid = (u8 *)edid;
- raw_edid += (edid->extensions * EDID_LENGTH);
- last_block = (struct edid *)raw_edid;
-
- /* block type extension */
- drm_edid_block_valid(raw_edid, 1, false, &is_edid_corrupt);
- if (!is_edid_corrupt)
- return last_block->checksum;
-
- DRM_ERROR("Invalid block, no checksum\n");
- return 0;
+ return edid->checksum;
}
void dp_panel_handle_sink_request(struct dp_panel *dp_panel)
