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References: <20220317131250.1481275-1-kieran.bingham+renesas@ideasonboard.com> <20220317131250.1481275-4-kieran.bingham+renesas@ideasonboard.com> <CAD=FV=WmkYg33qsXS4znQ8K2H0xVhJfZoPC+HjKt-rPhZ_R4KA@mail.gmail.com>
Subject: Re: [PATCH v4 3/3] drm/bridge: ti-sn65dsi86: Support hotplug detection
From:   Kieran Bingham <kieran.bingham+renesas@ideasonboard.com>
Cc:     Sam Ravnborg <sam@ravnborg.org>,
        Laurent Pinchart <laurent.pinchart@ideasonboard.com>,
        Linux-Renesas <linux-renesas-soc@vger.kernel.org>,
        dri-devel <dri-devel@lists.freedesktop.org>,
        Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>,
        Andrzej Hajda <andrzej.hajda@intel.com>,
        Neil Armstrong <narmstrong@baylibre.com>,
        Robert Foss <robert.foss@linaro.org>,
        Jonas Karlman <jonas@kwiboo.se>,
        Jernej Skrabec <jernej.skrabec@gmail.com>,
        David Airlie <airlied@linux.ie>,
        Daniel Vetter <daniel@ffwll.ch>,
        open list <linux-kernel@vger.kernel.org>
To:     Doug Anderson <dianders@chromium.org>
Date:   Wed, 23 Mar 2022 22:11:25 +0000
Message-ID: <164807348512.1092274.4092058426102648400@Monstersaurus>
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Quoting Doug Anderson (2022-03-23 21:47:17)
> Hi,
>=20
> On Thu, Mar 17, 2022 at 6:13 AM Kieran Bingham
> <kieran.bingham+renesas@ideasonboard.com> wrote:
> >
> > @@ -1241,9 +1350,32 @@ static int ti_sn_bridge_probe(struct auxiliary_d=
evice *adev,
> >         pdata->bridge.type =3D pdata->next_bridge->type =3D=3D DRM_MODE=
_CONNECTOR_DisplayPort
> >                            ? DRM_MODE_CONNECTOR_DisplayPort : DRM_MODE_=
CONNECTOR_eDP;
> >
> > -       if (pdata->bridge.type =3D=3D DRM_MODE_CONNECTOR_DisplayPort)
> > +       if (pdata->bridge.type =3D=3D DRM_MODE_CONNECTOR_DisplayPort) {
> >                 pdata->bridge.ops =3D DRM_BRIDGE_OP_EDID;
> >
> > +               if (!pdata->no_hpd)
> > +                       pdata->bridge.ops |=3D DRM_BRIDGE_OP_DETECT;
> > +       }
> > +
> > +       if (!pdata->no_hpd && pdata->irq > 0) {
> > +               ret =3D devm_request_threaded_irq(pdata->dev, pdata->ir=
q, NULL,
> > +                                               ti_sn65dsi86_irq_handle=
r,
> > +                                               IRQF_ONESHOT, "sn65dsi8=
6-irq",
> > +                                               pdata);
> > +               if (ret)
> > +                       return dev_err_probe(pdata->dev, ret,
> > +                                            "Failed to register DP int=
errupt\n");
> > +
> > +               /* Enable IRQ based HPD */
> > +               pdata->bridge.ops |=3D DRM_BRIDGE_OP_HPD;
> > +
> > +               /*
> > +                * Keep the IRQ disabled initially. It will only be ena=
bled when
> > +                * requested through ti_sn_bridge_hpd_enable().
> > +                */
> > +               disable_irq(pdata->irq);
>=20
> Instead, I think you should use `IRQF_NO_AUTOEN` which makes sure that
> no matter what the state of the hardware is your IRQ won't fire
> "early". ...and, of course, it saves a line of code. ;-)
>=20
> Other than that this looks nice to me now so feel free to add my

Aha, thanks, - didn't realise I could do that. I'll remove the
disable_irq, and move the coment above devm_request_threaded_irq, it
still makes sense there with the flag.

I believe I've got the format handling solved on the NO_CONNECTOR patch
from Rob/Sam, so I'm just waiting for some spare cycles to get back and
clean up - and repost the whole of this work as a new series,
incorporating Sam, Rob and Laurent's work with this on top.

--
Kieran


> Reviewed-by tag after the above is fixed.
>=20
> -Doug