[PATCH] drm/panel: kd35t133: allow using non-continuous dsi clock

[PATCH] drm/panel: kd35t133: allow using non-continuous dsi clock

[Heiko Stuebner]

The panel is able to work when dsi clock is non-continuous, thus
the system power consumption can be reduced using such feature.

Add MIPI_DSI_CLOCK_NON_CONTINUOUS to panel's mode_flags.

Also the flag actually becomes necessary after
commit c6d94e37bdbb ("drm/bridge/synopsys: dsi: add support for non-continuous HS clock")
and without it the panel only emits stripes instead of output.

Signed-off-by: Heiko Stuebner <heiko@sntech.de>
---
 drivers/gpu/drm/panel/panel-elida-kd35t133.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/panel/panel-elida-kd35t133.c b/drivers/gpu/drm/panel/panel-elida-kd35t133.c
index bc36aa3c1123..fe5ac3ef9018 100644
--- a/drivers/gpu/drm/panel/panel-elida-kd35t133.c
+++ b/drivers/gpu/drm/panel/panel-elida-kd35t133.c
@@ -265,7 +265,8 @@ static int kd35t133_probe(struct mipi_dsi_device *dsi)
 	dsi->lanes = 1;
 	dsi->format = MIPI_DSI_FMT_RGB888;
 	dsi->mode_flags = MIPI_DSI_MODE_VIDEO | MIPI_DSI_MODE_VIDEO_BURST |
-			  MIPI_DSI_MODE_LPM | MIPI_DSI_MODE_EOT_PACKET;
+			  MIPI_DSI_MODE_LPM | MIPI_DSI_MODE_EOT_PACKET |
+			  MIPI_DSI_CLOCK_NON_CONTINUOUS;
 
 	drm_panel_init(&ctx->panel, &dsi->dev, &kd35t133_funcs,
 		       DRM_MODE_CONNECTOR_DSI);
-- 
2.29.2

Re: [PATCH] drm/panel: kd35t133: allow using non-continuous dsi clock

[Ezequiel Garcia]

On Sat, 6 Feb 2021 at 10:50, Heiko Stuebner <heiko@sntech.de> wrote:
>
> The panel is able to work when dsi clock is non-continuous, thus
> the system power consumption can be reduced using such feature.
>
> Add MIPI_DSI_CLOCK_NON_CONTINUOUS to panel's mode_flags.
>
> Also the flag actually becomes necessary after
> commit c6d94e37bdbb ("drm/bridge/synopsys: dsi: add support for non-continuous HS clock")
> and without it the panel only emits stripes instead of output.
>

Looks like c6d94e37bdbb landed in v5.10, so we should add:

Fixes: c6d94e37bdbb ("drm/bridge/synopsys: dsi: add support for
non-continuous HS clock")
Cc: stable@vger.kernel.org # 5.10+

With this fix, my Odroid Go2 has display.

Tested-by: Ezequiel Garcia <ezequiel@collabora.com>

Thanks,
Ezequiel

> Signed-off-by: Heiko Stuebner <heiko@sntech.de>
> ---
>  drivers/gpu/drm/panel/panel-elida-kd35t133.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/panel/panel-elida-kd35t133.c b/drivers/gpu/drm/panel/panel-elida-kd35t133.c
> index bc36aa3c1123..fe5ac3ef9018 100644
> --- a/drivers/gpu/drm/panel/panel-elida-kd35t133.c
> +++ b/drivers/gpu/drm/panel/panel-elida-kd35t133.c
> @@ -265,7 +265,8 @@ static int kd35t133_probe(struct mipi_dsi_device *dsi)
>         dsi->lanes = 1;
>         dsi->format = MIPI_DSI_FMT_RGB888;
>         dsi->mode_flags = MIPI_DSI_MODE_VIDEO | MIPI_DSI_MODE_VIDEO_BURST |
> -                         MIPI_DSI_MODE_LPM | MIPI_DSI_MODE_EOT_PACKET;
> +                         MIPI_DSI_MODE_LPM | MIPI_DSI_MODE_EOT_PACKET |
> +                         MIPI_DSI_CLOCK_NON_CONTINUOUS;
>
>         drm_panel_init(&ctx->panel, &dsi->dev, &kd35t133_funcs,
>                        DRM_MODE_CONNECTOR_DSI);
> --
> 2.29.2
>
> _______________________________________________
> dri-devel mailing list
> dri-devel@lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/dri-devel

Re: [PATCH] drm/panel: kd35t133: allow using non-continuous dsi clock

[Heiko Stuebner]

On Sat, 6 Feb 2021 14:50:20 +0100, Heiko Stuebner wrote:
> The panel is able to work when dsi clock is non-continuous, thus
> the system power consumption can be reduced using such feature.
> 
> Add MIPI_DSI_CLOCK_NON_CONTINUOUS to panel's mode_flags.
> 
> Also the flag actually becomes necessary after
> commit c6d94e37bdbb ("drm/bridge/synopsys: dsi: add support for non-continuous HS clock")
> and without it the panel only emits stripes instead of output.

Applied, thanks!

[1/1] drm/panel: kd35t133: allow using non-continuous dsi clock
      commit: 54dab3a718f7094532daf7d25cd14121a0e00e34

Best regards,
-- 
Heiko Stuebner <heiko@sntech.de>