Thank you for your contribution! Sashiko AI review found 2 potential issue(s) 
to consider:
- [Medium] Missing error reporting for drm_edid_connector_update() on the 
connect path, contradicting the commit message.
- [Low] The SCDC sync call on the disconnect path is a guaranteed no-op, 
leaving the scrambler state unhandled and introducing dead error-handling code.
--

commit 41a712cbfad2ca468ecdd91cc77914f264d5dce6
Author: Cristian Ciocaltea <[email protected]>

drm/display: hdmi-state-helper: Sync SCDC state on hotplug

This commit attempts to synchronize SCDC status on hotplug events by hooking
drm_connector_hdmi_sync_scdc() into the connect and disconnect paths. It also
aims to report errors from drm_edid_connector_update() for consistency.

> diff --git a/drivers/gpu/drm/display/drm_hdmi_state_helper.c 
> b/drivers/gpu/drm/display/drm_hdmi_state_helper.c
> index 8045b1d17d6ec..1e269b203b987 100644
> --- a/drivers/gpu/drm/display/drm_hdmi_state_helper.c
> +++ b/drivers/gpu/drm/display/drm_hdmi_state_helper.c
> @@ -1362,12 +1362,29 @@ drm_atomic_helper_connector_hdmi_update(struct 
> drm_connector *connector,
>                                       enum drm_connector_status status)
>  {
>       const struct drm_edid *drm_edid;
> +     int ret;
>  
>       if (status == connector_status_disconnected) {
> -             // TODO: also handle scramber, HDMI sink disconnected.
> +             /*
> +              * .detect_ctx() can only ever return a drm_connector_status or
> +              * -EDEADLK. Handle deadlocks, and report any !EDEADLK error.
> +              */
> +             ret = drm_connector_hdmi_sync_scdc(connector, false, ctx);
> +             if (ret) {
> +                     if (ret == -EDEADLK)
> +                             return ret;
> +
> +                     drm_warn(connector->dev, "Ignored SCDC sync error: 
> %d\n", ret);
> +             }

[Severity: Low]
Does this actually handle the scrambler state on disconnect?

If we look at drm_connector_hdmi_sync_scdc(), passing false for the plugged
parameter causes it to return 0 immediately:

int drm_connector_hdmi_sync_scdc(struct drm_connector *connector, bool plugged,
                                 struct drm_modeset_acquire_ctx *ctx)
{
        ...
        if (!connector || !plugged || !ctx)
                return 0;

Since ret will always be 0, the error handling block here is dead code, and the
scrambler state remains unhandled on the disconnect path.

> +
>               drm_connector_hdmi_audio_plugged_notify(connector, false);
> -             drm_edid_connector_update(connector, NULL);
> +
> +             ret = drm_edid_connector_update(connector, NULL);
> +             if (ret)
> +                     drm_warn(connector->dev, "Ignored EDID update error: 
> %d\n", ret);
> +
>               drm_connector_cec_phys_addr_invalidate(connector);
> +
>               return 0;
>       }
>  

[ ... ]

> @@ -1381,7 +1398,18 @@ drm_atomic_helper_connector_hdmi_update(struct 
> drm_connector *connector,
>       drm_edid_free(drm_edid);

[Severity: Medium]
The commit message states that errors from drm_edid_connector_update() will be
reported for consistency.

However, in drm_atomic_helper_connector_hdmi_update(), the return value of the
drm_edid_connector_update() call on the connect path (which happens just before
the drm_edid_free() call in the snippet above) is still being ignored:

        drm_edid_connector_update(connector, drm_edid);
        drm_edid_free(drm_edid);

Should we also add error reporting to this path to match the stated intent?

>  
>       if (status == connector_status_connected) {
> -             // TODO: also handle scramber, HDMI sink is now connected.
> +             /*
> +              * .detect_ctx() can only ever return a drm_connector_status or
> +              * -EDEADLK. Handle deadlocks, and report any !EDEADLK error.
> +              */
> +             ret = drm_connector_hdmi_sync_scdc(connector, true, ctx);
> +             if (ret) {
> +                     if (ret == -EDEADLK)
> +                             return ret;
> +
> +                     drm_warn(connector->dev, "Ignored SCDC sync error: 
> %d\n", ret);
> +             }
> +
>               drm_connector_hdmi_audio_plugged_notify(connector, true);
>               drm_connector_cec_phys_addr_set(connector);
>       }

-- 
Sashiko AI review ยท 
https://sashiko.dev/#/patchset/[email protected]?part=23

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