Re: [PATCH 2/3] PCI: brcmstb: Add regulator support

[Gregory Fong <gregory.0xf0@xxxxxxxxx>]

On Wed, Feb 12, 2020 at 7:58 PM Florian Fainelli <f.fainelli@xxxxxxxxx> wrote:
> On 2/12/2020 6:59 PM, Jaedon Shin wrote:
> > ARM-based Broadcom STB SoCs have GPIO-based voltage regulator for PCIe
> > turning off/on power supplies.
> >
> > Signed-off-by: Jaedon Shin <jaedon.shin@xxxxxxxxx>
> > ---
> >  drivers/gpio/gpio-brcmstb.c           | 13 ++++-
> >  drivers/pci/controller/pcie-brcmstb.c | 76 +++++++++++++++++++++++++++
> >  2 files changed, 88 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/gpio/gpio-brcmstb.c b/drivers/gpio/gpio-brcmstb.c
> > index 05e3f99ae59c..0cee5fcd2782 100644
> > --- a/drivers/gpio/gpio-brcmstb.c
> > +++ b/drivers/gpio/gpio-brcmstb.c
> > @@ -777,7 +777,18 @@ static struct platform_driver brcmstb_gpio_driver = {
> >       .remove = brcmstb_gpio_remove,
> >       .shutdown = brcmstb_gpio_shutdown,
> >  };
> > -module_platform_driver(brcmstb_gpio_driver);
> > +
> > +static int __init brcmstb_gpio_init(void)
> > +{
> > +     return platform_driver_register(&brcmstb_gpio_driver);
> > +}
> > +subsys_initcall(brcmstb_gpio_init);
> > +
> > +static void __exit brcmstb_gpio_exit(void)
> > +{
> > +     platform_driver_unregister(&brcmstb_gpio_driver);
> > +}
> > +module_exit(brcmstb_gpio_exit);
>
> We do this in the downstream tree, but there is no reason, we should
> just deal with EPROBE_DEFER being returned from the regulator subsystem
> until the GPIO provide is available.
>

Agreed, also see this thread from January 2016:
https://lore.kernel.org/linux-mips/568EAA99.1020603@xxxxxxxxx/

Best regards,
Gregory