This is a note to let you know that I've just added the patch titled
drm/msm/dsi: set default num_data_lanes
to the 4.14-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-dsi-set-default-num_data_lanes.patch
and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 44f79ac8de7da389aa34484b4e6112ca2c3e9625
Author: Philip Chen <philipchen@xxxxxxxxxxxx>
Date: Sat Oct 30 10:08:50 2021 -0700
drm/msm/dsi: set default num_data_lanes
[ Upstream commit cd92cc187c053ab010a1570e2d61d68394a5c725 ]
If "data_lanes" property of the dsi output endpoint is missing in
the DT, num_data_lanes would be 0 by default, which could cause
dsi_host_attach() to fail if dsi->lanes is set to a non-zero value
by the bridge driver.
According to the binding document of msm dsi controller, the
input/output endpoint of the controller is expected to have 4 lanes.
So let's set num_data_lanes to 4 by default.
Signed-off-by: Philip Chen <philipchen@xxxxxxxxxxxx>
Reviewed-by: Douglas Anderson <dianders@xxxxxxxxxxxx>
Reviewed-by: Stephen Boyd <swboyd@xxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20211030100812.1.I6cd9af36b723fed277d34539d3b2ba4ca233ad2d@changeid
Signed-off-by: Rob Clark <robdclark@xxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/gpu/drm/msm/dsi/dsi_host.c b/drivers/gpu/drm/msm/dsi/dsi_host.c
index ef4e81d774464..d49f177481195 100644
--- a/drivers/gpu/drm/msm/dsi/dsi_host.c
+++ b/drivers/gpu/drm/msm/dsi/dsi_host.c
@@ -1563,6 +1563,8 @@ static int dsi_host_parse_lane_data(struct msm_dsi_host *msm_host,
if (!prop) {
dev_dbg(dev,
"failed to find data lane mapping, using default\n");
+ /* Set the number of date lanes to 4 by default. */
+ msm_host->num_data_lanes = 4;
return 0;
}
