Re: [PATCH v3 3/3] memory: Add Broadcom STB memory controller driver

[Florian Fainelli]

On 8/12/22 10:36, Krzysztof Kozlowski wrote:
> On 12/08/2022 20:29, Florian Fainelli wrote:
> > On 8/9/22 02:58, Krzysztof Kozlowski wrote:
> > > On 02/08/2022 01:09, Florian Fainelli wrote:
> > > > Add support for configuring the Self Refresh Power Down (SRPD)
> > > > inactivity timeout on Broadcom STB chips. This is used to conserve power
> > > > when the DRAM activity is reduced.
> > >
> > >
> > > > +static int __maybe_unused brcmstb_memc_resume(struct device *dev)
> > > > +{
> > > > +	struct brcmstb_memc *memc = dev_get_drvdata(dev);
> > > > +
> > > > +	if (memc->timeout_cycles == 0)
> > > > +		return 0;
> > > > +
> > > > +	return brcmstb_memc_srpd_config(memc, memc->timeout_cycles);
> > > > +}
> > > > +
> > > > +static SIMPLE_DEV_PM_OPS(brcmstb_memc_pm_ops, brcmstb_memc_suspend,
> > > > +			 brcmstb_memc_resume);
> > > > +
> > > > +static struct platform_driver brcmstb_memc_driver = {
> > > > +	.probe = brcmstb_memc_probe,
> > > > +	.remove = brcmstb_memc_remove,
> > > > +	.driver = {
> > > > +		.name		= "brcmstb_memc",
> > > > +		.owner		= THIS_MODULE,
> > >
> > > No need, run coccinelle.
> > >
> > > > +		.of_match_table	= brcmstb_memc_of_match,
> > > > +		.pm		= &brcmstb_memc_pm_ops,
> > >
> > > Shouldn't this be pm_ptr()? and then no need for __maybe_unused in
> > > brcmstb_memc_resume/suspend.
> >
> > How can one can remove __maybe_unused without causing a warning for the
> > CONFIG_PM=n case, not that I needed to build to convince myself, but
> > still did anyway:
> >
> > drivers/memory/brcmstb_memc.c:275:12: warning: 'brcmstb_memc_resume'
> > defined but not used [-Wunused-function]
> >    static int brcmstb_memc_resume(struct device *dev)
> >               ^~~~~~~~~~~~~~~~~~~
> > drivers/memory/brcmstb_memc.c:252:12: warning: 'brcmstb_memc_suspend'
> > defined but not used [-Wunused-function]
> >    static int brcmstb_memc_suspend(struct device *dev)
> >               ^~~~~~~~~~~~~~~~~~~~
> >
> > unless you also implied enclosing those functions under an #if
> > IS_ENABLED(CONFIG_PM) or something which is IMHO less preferable.
>
> Are you sure you added also pm_ptr()? I don't see such warnings with W=1
> and final object does not have the functions (for a different driver but
> same principle).

Yes I am sure I added pm_ptr() see the v4 I just submitted. I don't see 
how the compiler cannot warn about the functions being unused the day 
they stop being referenced by the pm_ops structure which is eliminated?
--
Florian