Re: [PATCH 1/2] usb: gadget: udc: atmel: check rc of devm_gpiod_get_optional()

[Michael Walle]

Am 2022-07-05 20:53, schrieb Saravana Kannan:
> On Tue, Jul 5, 2022 at 6:19 AM Michael Walle <michael@xxxxxxxx> wrote:
> > devm_gpiod_get_optional() might still return an error code, esp.
> > EPROBE_DEFER. Return any errors.
> >
> > Signed-off-by: Michael Walle <michael@xxxxxxxx>
> > ---
> >  drivers/usb/gadget/udc/atmel_usba_udc.c | 2 ++
> >  1 file changed, 2 insertions(+)
> >
> > diff --git a/drivers/usb/gadget/udc/atmel_usba_udc.c 
> > b/drivers/usb/gadget/udc/atmel_usba_udc.c
> > index ae2bfbac603e..48355e0cee76 100644
> > --- a/drivers/usb/gadget/udc/atmel_usba_udc.c
> > +++ b/drivers/usb/gadget/udc/atmel_usba_udc.c
> > @@ -2165,6 +2165,8 @@ static struct usba_ep * atmel_udc_of_init(struct 
> > platform_device *pdev,
> >
> >         udc->vbus_pin = devm_gpiod_get_optional(&pdev->dev, 
> > "atmel,vbus",
> >                                                 GPIOD_IN);
> > +       if (IS_ERR(udc->vbus_pin))
> > +               return ERR_CAST(udc->vbus_pin);
>
> I'm confused. Is it really an optional resource if you treat a failure 
> to get it
> as a reason to fail a probe?

If the gpio isn't found NULL is returned.

-michael