This is a note to let you know that I've just added the patch titled
drm: mxsfb: Set fallback bus format when the bridge doesn't provide one
to the 5.15-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-mxsfb-set-fallback-bus-format-when-the-bridge-do.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 1153d6f3ae72e8cdfc119494d61628384447c625
Author: Guido Günther <agx@xxxxxxxxxxx>
Date: Mon Oct 11 15:41:27 2021 +0200
drm: mxsfb: Set fallback bus format when the bridge doesn't provide one
[ Upstream commit 1db060509903b29d63fe2e39c14fd0f99c4a447e ]
If a bridge doesn't do any bus format handling MEDIA_BUS_FMT_FIXED is
returned. Fallback to a reasonable default (MEDIA_BUS_FMT_RGB888_1X24) in
that case.
This unbreaks e.g. using mxsfb with the nwl bridge and mipi dsi panels.
Reported-by: Martin Kepplinger <martink@xxxxxxxxx>
Signed-off-by: Guido Günther <agx@xxxxxxxxxxx>
Reviewed-by: Lucas Stach <l.stach@xxxxxxxxxxxxxx>
Reviewed-by: Sam Ravnborg <sam@xxxxxxxxxxxx>
Acked-by: Stefan Agner <stefan@xxxxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/781f0352052cc50c823c199ef5f53c84902d0580.1633959458.git.agx@xxxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/gpu/drm/mxsfb/mxsfb_kms.c b/drivers/gpu/drm/mxsfb/mxsfb_kms.c
index 89dd618d78f31..b96ba348c68d9 100644
--- a/drivers/gpu/drm/mxsfb/mxsfb_kms.c
+++ b/drivers/gpu/drm/mxsfb/mxsfb_kms.c
@@ -362,6 +362,12 @@ static void mxsfb_crtc_atomic_enable(struct drm_crtc *crtc,
drm_atomic_get_new_bridge_state(state,
mxsfb->bridge);
bus_format = bridge_state->input_bus_cfg.format;
+ if (bus_format == MEDIA_BUS_FMT_FIXED) {
+ dev_warn_once(drm->dev,
+ "Bridge does not provide bus format, assuming MEDIA_BUS_FMT_RGB888_1X24.\n"
+ "Please fix bridge driver by handling atomic_get_input_bus_fmts.\n");
+ bus_format = MEDIA_BUS_FMT_RGB888_1X24;
+ }
}
/* If there is no bridge, use bus format from connector */
