Re: [PATCH v6 6/6] PCI: uniphier: Add error message when failed to get phy

[Kunihiko Hayashi]

Hi Rob,

On 2020/09/04 7:25, Rob Herring wrote:
> On Fri, Aug 21, 2020 at 1:05 AM Kunihiko Hayashi
> <hayashi.kunihiko@xxxxxxxxxxxxx> wrote:
> > On 2020/08/18 1:39, Rob Herring wrote:
> > > On Fri, Aug 7, 2020 at 4:25 AM Kunihiko Hayashi
> > > <hayashi.kunihiko@xxxxxxxxxxxxx> wrote:
> > > > Even if phy driver doesn't probe, the error message can't be distinguished
> > > > from other errors. This displays error message caused by the phy driver
> > > > explicitly.
> > > >
> > > > Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@xxxxxxxxxxxxx>
> > > > ---
> > > >    drivers/pci/controller/dwc/pcie-uniphier.c | 8 ++++++--
> > > >    1 file changed, 6 insertions(+), 2 deletions(-)
> > > >
> > > > diff --git a/drivers/pci/controller/dwc/pcie-uniphier.c b/drivers/pci/controller/dwc/pcie-uniphier.c
> > > > index 93ef608..7c8721e 100644
> > > > --- a/drivers/pci/controller/dwc/pcie-uniphier.c
> > > > +++ b/drivers/pci/controller/dwc/pcie-uniphier.c
> > > > @@ -489,8 +489,12 @@ static int uniphier_pcie_probe(struct platform_device *pdev)
> > > >                   return PTR_ERR(priv->rst);
> > > >
> > > >           priv->phy = devm_phy_optional_get(dev, "pcie-phy");
> > >
> > > The point of the optional variant vs. devm_phy_get() is whether or not
> > > you get an error message. So shouldn't you switch to devm_phy_get
> > > instead?
> > >
> > > > -       if (IS_ERR(priv->phy))
> > > > -               return PTR_ERR(priv->phy);
> > > > +       if (IS_ERR(priv->phy)) {
> > > > +               ret = PTR_ERR(priv->phy);
> > > > +               if (ret != -EPROBE_DEFER)
> > > > +                       dev_err(dev, "Failed to get phy (%d)\n", ret);
> > > > +               return ret;
> > > > +       }
> >
> > The 'phys' property is optional, so if there isn't 'phys' in the PCIe node,
> > devm_phy_get() returns -ENODEV, and devm_phy_optional_get() returns NULL.
> >
> > When devm_phy_optional_get() replaces devm_phy_get(),
> > condition for displaying an error message changes to:
> >
> >      (ret != -EPROBE_DEFER && ret != -ENODEV)
> >
> > This won't be simple, but should it be replaced?
>
> Nevermind. I was thinking we had some error prints for the optional
> vs. non-optional variants.
I understand.
As long as this phy is "optional", this doesn't need to print error message.
Once I cancel this patch, and leave the phy as "optional".

Thank you,

---
Best Regards
Kunihiko Hayashi