diff mbox series

drm/msm/dsi: set default num_data_lanes

Message ID 20211030100812.1.I6cd9af36b723fed277d34539d3b2ba4ca233ad2d@changeid (mailing list archive)
State New, archived
Headers show
Series drm/msm/dsi: set default num_data_lanes | expand

Commit Message

Philip Chen Oct. 30, 2021, 5:08 p.m. UTC
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@chromium.org>
---

 drivers/gpu/drm/msm/dsi/dsi_host.c | 2 ++
 1 file changed, 2 insertions(+)

Comments

Abhinav Kumar Nov. 1, 2021, 2:56 a.m. UTC | #1
On 10/30/2021 10:08 AM, Philip Chen wrote:
> 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@chromium.org>
Reviewed-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
> ---
>
>   drivers/gpu/drm/msm/dsi/dsi_host.c | 2 ++
>   1 file changed, 2 insertions(+)
>
> diff --git a/drivers/gpu/drm/msm/dsi/dsi_host.c b/drivers/gpu/drm/msm/dsi/dsi_host.c
> index c86b5090fae6..a32eb33dfc14 100644
> --- a/drivers/gpu/drm/msm/dsi/dsi_host.c
> +++ b/drivers/gpu/drm/msm/dsi/dsi_host.c
> @@ -1696,6 +1696,8 @@ static int dsi_host_parse_lane_data(struct msm_dsi_host *msm_host,
>   	if (!prop) {
>   		DRM_DEV_DEBUG(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;
>   	}
>
Doug Anderson Nov. 1, 2021, 6:02 p.m. UTC | #2
Hi,

On Sat, Oct 30, 2021 at 10:08 AM Philip Chen <philipchen@chromium.org> wrote:
>
> 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@chromium.org>
> ---
>
>  drivers/gpu/drm/msm/dsi/dsi_host.c | 2 ++
>  1 file changed, 2 insertions(+)

Reviewed-by: Douglas Anderson <dianders@chromium.org>
Stephen Boyd Nov. 1, 2021, 6:10 p.m. UTC | #3
Quoting Philip Chen (2021-10-30 10:08:50)
> 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@chromium.org>
> ---

Reviewed-by: Stephen Boyd <swboyd@chromium.org>
diff mbox series

Patch

diff --git a/drivers/gpu/drm/msm/dsi/dsi_host.c b/drivers/gpu/drm/msm/dsi/dsi_host.c
index c86b5090fae6..a32eb33dfc14 100644
--- a/drivers/gpu/drm/msm/dsi/dsi_host.c
+++ b/drivers/gpu/drm/msm/dsi/dsi_host.c
@@ -1696,6 +1696,8 @@  static int dsi_host_parse_lane_data(struct msm_dsi_host *msm_host,
 	if (!prop) {
 		DRM_DEV_DEBUG(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;
 	}