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References: <20220601094637.1200634-1-hsinyi@chromium.org> <20220601094637.1200634-4-hsinyi@chromium.org>
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From:   Doug Anderson <dianders@chromium.org>
Date:   Thu, 2 Jun 2022 14:43:21 -0700
Message-ID: <CAD=FV=XnA80P7BoaAX6JD9Q4ggnk4g4M3wmJFEDNij3+10aL4g@mail.gmail.com>
Subject: Re: [PATCH v2 3/8] drm/panel: panel-edp: Implement .get_orientation callback
To:     Hsin-Yi Wang <hsinyi@chromium.org>
Cc:     Chun-Kuang Hu <chunkuang.hu@kernel.org>,
        Hans de Goede <hdegoede@redhat.com>,
        Thierry Reding <thierry.reding@gmail.com>,
        Sam Ravnborg <sam@ravnborg.org>,
        Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
        Maxime Ripard <mripard@kernel.org>,
        Thomas Zimmermann <tzimmermann@suse.de>,
        Philipp Zabel <p.zabel@pengutronix.de>,
        David Airlie <airlied@linux.ie>,
        Daniel Vetter <daniel@ffwll.ch>,
        Matthias Brugger <matthias.bgg@gmail.com>,
        dri-devel <dri-devel@lists.freedesktop.org>,
        "moderated list:ARM/Mediatek SoC support" 
        <linux-mediatek@lists.infradead.org>,
        Rob Clark <robdclark@chromium.org>,
        Stephen Boyd <swboyd@chromium.org>,
        Rob Herring <robh+dt@kernel.org>,
        Linux ARM <linux-arm-kernel@lists.infradead.org>,
        LKML <linux-kernel@vger.kernel.org>
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Precedence: bulk

Hi,

On Wed, Jun 1, 2022 at 2:46 AM Hsin-Yi Wang <hsinyi@chromium.org> wrote:
>
> To return the orientation property to drm/kms driver.
>
> Signed-off-by: Hsin-Yi Wang <hsinyi@chromium.org>
> Reviewed-by: Hans de Goede <hdegoede@redhat.com>
> ---
>  drivers/gpu/drm/panel/panel-edp.c | 8 ++++++++
>  1 file changed, 8 insertions(+)
>
> diff --git a/drivers/gpu/drm/panel/panel-edp.c b/drivers/gpu/drm/panel/panel-edp.c
> index 1732b4f56e38..a2133581a72d 100644
> --- a/drivers/gpu/drm/panel/panel-edp.c
> +++ b/drivers/gpu/drm/panel/panel-edp.c
> @@ -609,6 +609,13 @@ static int panel_edp_get_timings(struct drm_panel *panel,
>         return p->desc->num_timings;
>  }
>
> +static enum drm_panel_orientation panel_edp_get_orientation(struct drm_panel *panel)
> +{
> +       struct panel_edp *p = to_panel_edp(panel);
> +
> +       return p->orientation;
> +}
> +
>  static int detected_panel_show(struct seq_file *s, void *data)
>  {
>         struct drm_panel *panel = s->private;
> @@ -637,6 +644,7 @@ static const struct drm_panel_funcs panel_edp_funcs = {
>         .prepare = panel_edp_prepare,
>         .enable = panel_edp_enable,
>         .get_modes = panel_edp_get_modes,
> +       .get_orientation = panel_edp_get_orientation,
>         .get_timings = panel_edp_get_timings,
>         .debugfs_init = panel_edp_debugfs_init,
>  };

I'm curious: should we be removing the old
drm_connector_set_panel_orientation() from panel_edp_get_modes()?
...or maybe you want to keep it for now because you're only adding
support to the mediatek driver and for other drivers the WARN_ON is
better than no orientation support at all?

Maybe you could put a comment next to the old
drm_connector_set_panel_orientation() saying that it's deprecated and
that drm drivers are expected to add a call to get_orientation()? Then
when people see the WARN_ON splat they'll quickly figure out how to
fix it. ...and eventually we can probably remove all the old calls
from get_modes() ?

-Doug