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References: <20230503163313.2640898-1-frieder@fris.de> <20230503163313.2640898-3-frieder@fris.de>
 <2225400.iZASKD2KPV@steina-w>
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From:   Fabio Estevam <festevam@gmail.com>
Date:   Tue, 16 May 2023 19:22:41 -0300
Message-ID: <CAOMZO5AiWM64tZgArUL89q5spuLD91R-pnURbfqPU9O0w54sQQ@mail.gmail.com>
Subject: Re: [PATCH v2 2/2] drm/bridge: ti-sn65dsi83: Fix enable/disable flow
 to meet spec
To:     Alexander Stein <alexander.stein@ew.tq-group.com>
Cc:     Andrzej Hajda <andrzej.hajda@intel.com>,
        Daniel Vetter <daniel@ffwll.ch>,
        David Airlie <airlied@gmail.com>,
        dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org,
        Neil Armstrong <neil.armstrong@linaro.org>,
        Robert Foss <rfoss@kernel.org>, Marek Vasut <marex@denx.de>,
        Jernej Skrabec <jernej.skrabec@gmail.com>,
        Jonas Karlman <jonas@kwiboo.se>,
        Frieder Schrempf <frieder@fris.de>,
        Frieder Schrempf <frieder.schrempf@kontron.de>,
        Laurent Pinchart <Laurent.pinchart@ideasonboard.com>,
        =?UTF-8?Q?Uwe_Kleine=2DK=C3=B6nig?= 
        <u.kleine-koenig@pengutronix.de>, Sam Ravnborg <sam@ravnborg.org>
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On Thu, May 4, 2023 at 6:12=E2=80=AFAM Alexander Stein
<alexander.stein@ew.tq-group.com> wrote:
>
> Am Mittwoch, 3. Mai 2023, 18:33:07 CEST schrieb Frieder Schrempf:
> > From: Frieder Schrempf <frieder.schrempf@kontron.de>
> >
> > The datasheet describes the following initialization flow including
> > minimum delay times between each step:
> >
> > 1. DSI data lanes need to be in LP-11 and the clock lane in HS mode
> > 2. toggle EN signal
> > 3. initialize registers
> > 4. enable PLL
> > 5. soft reset
> > 6. enable DSI stream
> > 7. check error status register
> >
> > To meet this requirement we need to make sure the host bridge's
> > pre_enable() is called first by using the pre_enable_prev_first
> > flag.
> >
> > Furthermore we need to split enable() into pre_enable() which covers
> > steps 2-5 from above and enable() which covers step 7 and is called
> > after the host bridge's enable().
> >
> > Signed-off-by: Frieder Schrempf <frieder.schrempf@kontron.de>
>
> Tested-by: Alexander Stein <alexander.stein@ew.tq-group.com> #TQMa8MxML/M=
Ba8Mx

Should this have a Fixes tag so that it could be backported to stable kerne=
ls?