Re: [PATCH v2 3/5] drm/msm/dp: Support up to 3 DP controllers

[Stephen Boyd <swboyd@chromium.org>]

Quoting Bjorn Andersson (2021-08-26 09:57:18)
> On Thu 26 Aug 00:13 PDT 2021, Stephen Boyd wrote:
> > Quoting Bjorn Andersson (2021-08-25 16:42:31)
> > > diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
> [..]
> > > @@ -203,8 +204,8 @@ static int dpu_kms_debugfs_init(struct msm_kms *kms, struct drm_minor *minor)
> > >         dpu_debugfs_vbif_init(dpu_kms, entry);
> > >         dpu_debugfs_core_irq_init(dpu_kms, entry);
> > >
> > > -       if (priv->dp)
> > > -               msm_dp_debugfs_init(priv->dp, minor);
> > > +       for (i = 0; i < ARRAY_SIZE(priv->dp); i++)
> > > +               msm_dp_debugfs_init(priv->dp[i], minor);
> >
> > Does this need the same if (!priv->dp) continue check like the other
> > loops over priv->dp?
> >
> [..]
> > > @@ -800,7 +809,8 @@ static int dpu_irq_postinstall(struct msm_kms *kms)
> > >         if (!priv)
> > >                 return -EINVAL;
> > >
> > > -       msm_dp_irq_postinstall(priv->dp);
> > > +       for (i = 0; i < ARRAY_SIZE(priv->dp); i++)
> > > +               msm_dp_irq_postinstall(priv->dp[i]);
> >
> > This one too? Or maybe those gained NULL pointer checks.
> >
>
> This already has a NULL check, that's why I added one to the adjacent
> msm_dp_debugfs_init() as well.

Ok.

>
> > >
> > >         return 0;
> > >  }
> > > diff --git a/drivers/gpu/drm/msm/dp/dp_display.c b/drivers/gpu/drm/msm/dp/dp_display.c
> [..]
> > > @@ -1194,6 +1230,10 @@ static int dp_display_probe(struct platform_device *pdev)
> > >         if (!dp)
> > >                 return -ENOMEM;
> > >
> > > +       dp->id = dp_display_get_id(pdev);
> >
> > Ah ok, it's signed for this error check. Maybe assign dp->id in the
> > function and return 0 instead of assigning it here?
> > dp_display_assign_id()
> >
>
> I like the fact that the "getter" doesn't have side effects, but making
> dp->id unsigned makes sense. So let's pay the price of a local signed
> variable here.
>

Sure. If that's the only change then feel free to add

Reviewed-by: Stephen Boyd <swboyd@chromium.org>

on the next version.