Re: [PATCH v2 3/5] thermal: devfreq_cooling: add new registration functions with Energy Model

[Lukasz Luba]

On 12/2/20 11:49 AM, Ionela Voinescu wrote:
> On Wednesday 02 Dec 2020 at 11:14:02 (+0000), Lukasz Luba wrote:
> > Hi Ionela,
> >
> > On 12/2/20 10:24 AM, Ionela Voinescu wrote:
> > > Hi Lukasz,
> > >
> > > On Wednesday 18 Nov 2020 at 12:03:56 (+0000), Lukasz Luba wrote:
> >
> > [snip]
> >
> > > > +	struct device_node *np = NULL;
> >
> > [snip]
> >
> > > > +
> > > > +	if (dev->of_node)
> > > > +		np = of_node_get(dev->of_node);
> > > > +
> > >
> > > Should np be checked before use? I'm not sure if it's better to do the
> > > assign first and then the check on np before use. It depends on the
> > > consequences of passing a NULL node pointer later on.
> >
> > The np is actually dev->of_node (or left NULL, as set at the begging).
> > The only meaning of the line above is to increment the counter and then
> > decrement if CONFIG_OF_DYNAMIC was used.
> > The devfreq_cooling_register() has np = NULL and the registration can
> > handle it, so we should be OK here as well.
>
> Yes, I just wanted to make sure later registration can handle np = NULL,
> or whether we need to bail out.
>
> In this case, you can drop both ifs - for (dev->of_node) before get and
> for np before put below, as of_node_get/of_node_put can handle NULL
> pointers themselves.

Right. I agree, I will resend this patch with that small change.
Thank you for having a look at it.

Lukasz

> Thanks,
> Ionela.