Re: [PATCH V2 1/2] opp: Allow dev_pm_opp_get_opp_table() to return -EPROBE_DEFER

From: Stephan Gerhold
Date: Fri Oct 16 2020 - 11:31:14 EST


On Fri, Oct 16, 2020 at 12:12:22PM +0100, Sudeep Holla wrote:
> On Fri, Oct 16, 2020 at 07:00:21AM +0100, Sudeep Holla wrote:
> > On Fri, Oct 16, 2020 at 09:54:34AM +0530, Viresh Kumar wrote:
> > > On 15-10-20, 19:05, Sudeep Holla wrote:
> > > > OK, this breaks with SCMI which doesn't provide clocks but manage OPPs
> > > > directly. Before this change clk_get(dev..) was allowed to fail and
> > > > --EPROBE_DEFER was not an error.
> > >
> > > I think the change in itself is fine. We should be returning from
> > > there if we get EPROBE_DEFER. The question is rather why are you
> > > getting EPROBE_DEFER here ?
> > >
> >
> > Ah OK, I didn't spend too much time, saw -EPROBE_DEFER, just reverted
> > this patch and it worked. I need to check it in detail yet.
> >
>
> You confused me earlier. As I said there will be no clock provider
> registered for SCMI CPU/Dev DVFS.
> opp_table->clk = clk_get(dev, NULL);
> will always return -EPROBE_DEFER as there is no clock provider for dev.

Shouldn't it return -ENOENT if there is no clock for the SCMI case?
With -EPROBE_DEFER I would expect that it shows up at some point.

I tried to avoid a situation like this by ignoring all errors
!= -EPROBE_DEFER. So if clk_get(dev, NULL) would return -ENOENT
everything should work as expected...

Thanks,
Stephan