Re: Re: [PATCH] media: vsp1: Fix runtime PM imbalance in vsp1_probe

From: Laurent Pinchart
Date: Mon Jun 08 2020 - 07:55:23 EST


Hi Geert,

On Mon, Jun 08, 2020 at 09:39:51AM +0200, Geert Uytterhoeven wrote:
> Hi Dinghao,
>
> On Mon, Jun 8, 2020 at 5:03 AM <dinghao.liu@xxxxxxxxxx> wrote:
> > > > I wonder how many bugs we have today, and how many bugs will keep
> > > > appearing in the future, due to this historical design mistake :-(
> >
> > Good question. It's hard to say if this is a design mistake (some use
> > of this API does not check its return value and expects it always to
> > increment the usage counter). But it does make developers misuse it easier.
>
> On Renesas SoCs, I believe these can only fail if there's something
> seriously wrong, which means the system could never have gotten this far
> in the boot sequence anyway. That's why I tend not to check the result
> of pm_runtime_get_sync() at all (on drivers for Renesas SoCs).

There are lots of return paths from rpm_resume() that return an error,
more than just rpm_callback(). Do you consider that none of them are
valid errors that drivers need to handle ?

--
Regards,

Laurent Pinchart