On Tue, Apr 10, 2018 at 01:28:33AM +0000, Yoshihiro Shimoda wrote:
> Hi Simon-san,
>
> > From: Simon Horman, Sent: Monday, April 9, 2018 8:58 PM
> >
> > On Mon, Apr 02, 2018 at 09:21:34PM +0900, Yoshihiro Shimoda wrote:
> > > This patch fixes an issue that this driver cannot call phy_init()
> > > if a gadget driver is alreadly loaded because usb_add_gadget_udc()
> > > might call renesas_usb3_start() via .udc_start.
> > >
> > > Fixes: 279d4bc64060 ("usb: gadget: udc: renesas_usb3: add support for generic phy")
> > > Cc: <stable@xxxxxxxxxxxxxxx> # v4.15+
> > > Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx>
> > > ---
> > > drivers/usb/gadget/udc/renesas_usb3.c | 16 ++++++++--------
> > > 1 file changed, 8 insertions(+), 8 deletions(-)
> >
> > Reviewed-by: Simon Horman <horms+renesas@xxxxxxxxxxxx>
> >
> >
> > Please see some suggestions for follow-up lower-priority patches below.
>
> Thank you for the review and suggestions!
>
> > >
> > > diff --git a/drivers/usb/gadget/udc/renesas_usb3.c b/drivers/usb/gadget/udc/renesas_usb3.c
> > > index 738b734..671bac3 100644
> > > --- a/drivers/usb/gadget/udc/renesas_usb3.c
> > > +++ b/drivers/usb/gadget/udc/renesas_usb3.c
> > > @@ -2632,6 +2632,14 @@ static int renesas_usb3_probe(struct platform_device *pdev)
> > > if (ret < 0)
> > > goto err_alloc_prd;
> > >
> > > + /*
> > > + * This is an optional. So, if this driver cannot get a phy,
> > > + * this driver will not handle a phy anymore.
> > > + */
> >
> > nit: s/an optional/optional/
>
> Oops. I will fix and submit v2 patches.
>
> > > + usb3->phy = devm_phy_get(&pdev->dev, "usb");
> > > + if (IS_ERR(usb3->phy))
> > > + usb3->phy = NULL;
> >
> > I think this will unintentionally ignore errors other than the
> > non-existence of the device, f.e. a memory allocation failure
> > in devm_phy_get().
> >
> > So perhaps something like this, as per phy_optional_get(), would be better?
> >
> > usb3->phy = devm_phy_get(&pdev->dev, "usb");
> > if (IS_ERR(usb3->phy) && (PTR_ERR(usb3->phy) == -ENODEV))
> > usb3->phy = NULL;
>
> Thank you for the suggestion. I agree with you.
> I think I should use devm_phy_optional_get() instead of dev_phy_get(), as you mentioned :)
> So, I will fix the code by using devm_phy_optional_get() first, and then fix this.
Thanks, I agree that would be a good fix.
But perhaps it is better as a follow-up?
