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References: <20181116163916.29621-1-jagan@amarulasolutions.com>
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In-Reply-To: <20181119083833.d7ysiv3tenabtrdj@flea>
From:   Jagan Teki <jagan@amarulasolutions.com>
Date:   Mon, 19 Nov 2018 17:06:32 +0530
Message-ID: <CAMty3ZCsEYFJOQAFTf3FspQWMzD-tiW_njuyCJ950RZ=Y6apEw@mail.gmail.com>
Subject: Re: [PATCH v2 06/12] drm/sun4i: sun6i_mipi_dsi: Probe tcon0 during dsi_bind
To:     Maxime Ripard <maxime.ripard@bootlin.com>
Cc:     Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
        Sean Paul <sean@poorly.run>, David Airlie <airlied@linux.ie>,
        Rob Herring <robh+dt@kernel.org>, Chen-Yu Tsai <wens@csie.org>,
        Icenowy Zheng <icenowy@aosc.io>,
        Jernej Skrabec <jernej.skrabec@siol.net>,
        Vasily Khoruzhick <anarsoul@gmail.com>,
        Thierry Reding <thierry.reding@gmail.com>,
        Mark Rutland <mark.rutland@arm.com>,
        dri-devel <dri-devel@lists.freedesktop.org>,
        devicetree <devicetree@vger.kernel.org>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        linux-arm-kernel <linux-arm-kernel@lists.infradead.org>,
        Michael Trimarchi <michael@amarulasolutions.com>,
        TL Lim <tllim@pine64.org>, linux-sunxi@googlegroups.com,
        linux-amarula@amarulasolutions.com
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On Mon, Nov 19, 2018 at 2:08 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
>
> On Fri, Nov 16, 2018 at 10:09:10PM +0530, Jagan Teki wrote:
> > Probe tcon0 during dsi_bind, so-that the tcon attributes like
> > divider value, clock rate can get whenever it need.
> >
> > Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
> > ---
> >  drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c | 7 +++++++
> >  drivers/gpu/drm/sun4i/sun6i_mipi_dsi.h | 1 +
> >  2 files changed, 8 insertions(+)
> >
> > diff --git a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
> > index d60955880c43..66a01061e51d 100644
> > --- a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
> > +++ b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
> > @@ -25,6 +25,7 @@
> >  #include <drm/drm_panel.h>
> >
> >  #include "sun4i_drv.h"
> > +#include "sun4i_tcon.h"
> >  #include "sun6i_mipi_dsi.h"
> >
> >  #include <video/mipi_display.h>
> > @@ -1007,6 +1008,7 @@ static int sun6i_dsi_bind(struct device *dev, struct device *master,
> >       struct drm_device *drm = data;
> >       struct sun4i_drv *drv = drm->dev_private;
> >       struct sun6i_dsi *dsi = dev_get_drvdata(dev);
> > +     struct sun4i_tcon *tcon0 = sun4i_get_tcon0(drm);
> >       int ret;
> >
> >       if (!dsi->panel)
> > @@ -1014,6 +1016,11 @@ static int sun6i_dsi_bind(struct device *dev, struct device *master,
> >
> >       dsi->drv = drv;
> >
> > +     if (!tcon0)
> > +             return -EPROBE_DEFER;
>
> You can't fall in that condition. The component framework won't call
> bind unless every components have been probed.

Since tcon0 is already probed is it? if so I can return -EINVAL is it ok?