Re: [PATCH] drm/msm/dp: only signal audio when disconnected detected at dp_pm_resume

[Stephen Boyd]

Quoting Kuogee Hsieh (2021-09-28 09:11:12)
> Only signal audio when disconnected detected at dp_pm_resume since
> connected status will be signaled to audio at next plugin handler.

Please add more details. This says what the patch does but it would be
better if it included why it is important. Does it fix something?
There's a fixes tag so it must fix something. Is it bad to signal audio
plug change on resume when it hasn't actually changed from last time?
Why is that bad? What if the cable is unplugged and then plugged in
before resume? Does audio still get signalled in that case?

>
> Fixes: 078867ce04ed ("drm/msm/dp: signal audio plugged change at dp_pm_resume")
> Signed-off-by: Kuogee Hsieh <khsieh@xxxxxxxxxxxxxx>
> ---
>  drivers/gpu/drm/msm/dp/dp_display.c | 10 +++++-----
>  1 file changed, 5 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/gpu/drm/msm/dp/dp_display.c b/drivers/gpu/drm/msm/dp/dp_display.c
> index 0e543a03..6f13008 100644
> --- a/drivers/gpu/drm/msm/dp/dp_display.c
> +++ b/drivers/gpu/drm/msm/dp/dp_display.c
> @@ -1356,14 +1356,14 @@ static int dp_pm_resume(struct device *dev)
>          * can not declared display is connected unless
>          * HDMI cable is plugged in and sink_count of
>          * dongle become 1
> +        * also only signal audio when disconnected
>          */
> -       if (dp->link->sink_count)
> +       if (dp->link->sink_count) {
>                 dp->dp_display.is_connected = true;
> -       else
> +       } else {
>                 dp->dp_display.is_connected = false;
> -
> -       dp_display_handle_plugged_change(g_dp_display,
> -                               dp->dp_display.is_connected);
> +               dp_display_handle_plugged_change(g_dp_display, false);
> +       }