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From: Doug Anderson <dianders@chromium.org>
Date: Tue, 9 Jan 2024 08:52:12 -0800
Message-ID: <CAD=FV=WjjH3BCDf-OnX=zdk201uMu+YJvKVBhVmMa4GqNinacw@mail.gmail.com>
Subject: Re: [PATCH v2] drm/bridge: parade-ps8640: Ensure bridge is suspended
 in .post_disable()
To: Pin-yen Lin <treapking@chromium.org>
Cc: Andrzej Hajda <andrzej.hajda@intel.com>, Neil Armstrong <neil.armstrong@linaro.org>, 
	Robert Foss <rfoss@kernel.org>, Laurent Pinchart <Laurent.pinchart@ideasonboard.com>, 
	Jonas Karlman <jonas@kwiboo.se>, Jernej Skrabec <jernej.skrabec@gmail.com>, 
	dri-devel@lists.freedesktop.org, Sean Paul <seanpaul@chromium.org>, 
	linux-kernel@vger.kernel.org
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Hi,

On Tue, Jan 9, 2024 at 4:05=E2=80=AFAM Pin-yen Lin <treapking@chromium.org>=
 wrote:
>
> The ps8640 bridge seems to expect everything to be power cycled at the
> disable process, but sometimes ps8640_aux_transfer() holds the runtime
> PM reference and prevents the bridge from suspend.
>
> Prevent that by introducing a mutex lock between ps8640_aux_transfer()
> and .post_disable() to make sure the bridge is really powered off.
>
> Fixes: 826cff3f7ebb ("drm/bridge: parade-ps8640: Enable runtime power man=
agement")
> Signed-off-by: Pin-yen Lin <treapking@chromium.org>
> ---
>
> Changes in v2:
> - Use mutex instead of the completion and autosuspend hack
>
>  drivers/gpu/drm/bridge/parade-ps8640.c | 16 ++++++++++++++++
>  1 file changed, 16 insertions(+)

This looks OK to me now.

Reviewed-by: Douglas Anderson <dianders@chromium.org>

I'll let it stew on the mailing list for ~1 week and then land it in
drm-misc-fixes unless there are additional comments.

-Doug