linux-kernel - Re: [PATCH] drm/msm/dp: only signal audio when disconnected detected at dp_pm

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date:   Tue, 28 Sep 2021 13:42:34 -0700
From:   Stephen Boyd <swboyd@...omium.org>
To:     Kuogee Hsieh <khsieh@...eaurora.org>, agross@...nel.org,
        bjorn.andersson@...aro.org, robdclark@...il.com, sean@...rly.run,
        vkoul@...nel.org
Cc:     abhinavk@...eaurora.org, aravindh@...eaurora.org,
        freedreno@...ts.freedesktop.org, dri-devel@...ts.freedesktop.org,
        linux-arm-msm@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH] drm/msm/dp: only signal audio when disconnected detected
 at dp_pm_resume

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@...eaurora.org>
> ---
>  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);
> +       }