On Fri, Sep 11, 2026 at 11:51:05AM +0300, YİĞİTCAN KAVAKLI via B4 Relay wrote:
> From: YİĞİTCAN KAVAKLI <[email protected]>
>
> In dsi_op_mode_config(), entering video mode sets DSI_CTRL_VID_MODE_EN
> without clearing DSI_CTRL_CMD_MODE_EN, and entering command mode sets
> DSI_CTRL_CMD_MODE_EN without clearing DSI_CTRL_VID_MODE_EN.
>
> Ensure explicit mutual exclusion by clearing the opposing enable bit
> when switching operational modes to prevent hardware bus collisions.
>
> Signed-off-by: YİĞİTCAN KAVAKLI <[email protected]>
> ---
> drivers/gpu/drm/msm/dsi/dsi_host.c | 6 +++++-
> 1 file changed, 5 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/msm/dsi/dsi_host.c
> b/drivers/gpu/drm/msm/dsi/dsi_host.c
> index
> 7e4e3718b536c92dc555de213042857379499447..b9e2867d435a3ad8b6db6b57c440bbd827180b6e
> 100644
> --- a/drivers/gpu/drm/msm/dsi/dsi_host.c
> +++ b/drivers/gpu/drm/msm/dsi/dsi_host.c
> @@ -1094,7 +1094,9 @@ static void dsi_timing_setup(struct msm_dsi_host
> *msm_host, bool is_bonded_dsi)
> dsi_write(msm_host, REG_DSI_ACTIVE_HSYNC,
> DSI_ACTIVE_HSYNC_START(hs_start) |
> DSI_ACTIVE_HSYNC_END(hs_end));
> - dsi_write(msm_host, REG_DSI_ACTIVE_VSYNC_HPOS, 0);
> + dsi_write(msm_host, REG_DSI_ACTIVE_VSYNC_HPOS,
> + DSI_ACTIVE_VSYNC_HPOS_START(hs_start) |
> + DSI_ACTIVE_VSYNC_HPOS_END(vs_end));
This fixup is unrelated, please split it to a separate commit. Also, I
don't see corresponding code in the downstream driver. Do you have a
reference?
> dsi_write(msm_host, REG_DSI_ACTIVE_VSYNC_VPOS,
> DSI_ACTIVE_VSYNC_VPOS_START(vs_start) |
> DSI_ACTIVE_VSYNC_VPOS_END(vs_end));
> @@ -1168,8 +1170,10 @@ static void dsi_op_mode_config(struct msm_dsi_host
> *msm_host,
> DSI_IRQ_MASK_VIDEO_DONE, 0);
> } else {
> if (video_mode) {
> + dsi_ctrl &= ~DSI_CTRL_CMD_MODE_EN;
> dsi_ctrl |= DSI_CTRL_VID_MODE_EN;
> } else { /* command mode */
> + dsi_ctrl &= ~DSI_CTRL_VID_MODE_EN;
> dsi_ctrl |= DSI_CTRL_CMD_MODE_EN;
> dsi_intr_ctrl(msm_host, DSI_IRQ_MASK_CMD_MDP_DONE, 1);
For this one:
Fixes: a689554ba6ed ("drm/msm: Initial add DSI connector support")
> }
>
> --
> 2.47.3
>
>
--
With best wishes
Dmitry
