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References: <20230314110043.2139111-1-treapking@chromium.org>
In-Reply-To: <20230314110043.2139111-1-treapking@chromium.org>
From:   Robert Foss <rfoss@kernel.org>
Date:   Tue, 14 Mar 2023 12:19:08 +0100
Message-ID: <CAN6tsi7d9XPfQmp+uSjbsgS3YeLJF_Ozp4ZjoaVOF2oWJQgLtw@mail.gmail.com>
Subject: Re: [PATCH 1/2] drm/bridge: ps8640: Skip redundant bridge enable
To:     Pin-yen Lin <treapking@chromium.org>
Cc:     Douglas Anderson <dianders@chromium.org>,
        Andrzej Hajda <andrzej.hajda@intel.com>,
        Neil Armstrong <neil.armstrong@linaro.org>,
        Laurent Pinchart <Laurent.pinchart@ideasonboard.com>,
        Jonas Karlman <jonas@kwiboo.se>,
        Jernej Skrabec <jernej.skrabec@gmail.com>,
        David Airlie <airlied@gmail.com>,
        Daniel Vetter <daniel@ffwll.ch>,
        Enric Balletbo i Serra <enric.balletbo@collabora.com>,
        linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org
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On Tue, Mar 14, 2023 at 12:01=E2=80=AFPM Pin-yen Lin <treapking@chromium.or=
g> wrote:
>
> Skip the drm_bridge_chain_pre_enable call when the bridge is already
> pre_enabled. This make pre_enable and post_disable (thus
> pm_runtime_get/put) symmetric.
>
> Fixes: 46f206304db0 ("drm/bridge: ps8640: Rework power state handling")
> Signed-off-by: Pin-yen Lin <treapking@chromium.org>
> ---
>
>  drivers/gpu/drm/bridge/parade-ps8640.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/bridge/parade-ps8640.c b/drivers/gpu/drm/bri=
dge/parade-ps8640.c
> index 4b361d7d5e44..08de501c436e 100644
> --- a/drivers/gpu/drm/bridge/parade-ps8640.c
> +++ b/drivers/gpu/drm/bridge/parade-ps8640.c
> @@ -557,7 +557,8 @@ static struct edid *ps8640_bridge_get_edid(struct drm=
_bridge *bridge,
>          * EDID, for this chip, we need to do a full poweron, otherwise i=
t will
>          * fail.
>          */
> -       drm_atomic_bridge_chain_pre_enable(bridge, connector->state->stat=
e);
> +       if (poweroff)
> +               drm_atomic_bridge_chain_pre_enable(bridge, connector->sta=
te->state);
>
>         edid =3D drm_get_edid(connector,
>                             ps_bridge->page[PAGE0_DP_CNTL]->adapter);
> --
> 2.40.0.rc1.284.g88254d51c5-goog
>

Reviewed-by: Robert Foss <rfoss@kernel.org>