Re: [PATCH v4 9/9] usb: chipidea: add support to the generic PHY framework in ChipIdea

From: Antoine Tenart
Date: Thu Sep 11 2014 - 11:42:33 EST


Peter,

On Thu, Sep 11, 2014 at 08:54:47AM +0800, Peter Chen wrote:
> On Wed, Sep 03, 2014 at 09:40:40AM +0200, Antoine Tenart wrote:
> > @@ -595,23 +639,27 @@ static int ci_hdrc_probe(struct platform_device *pdev)
> > return -ENODEV;
> > }
> >
> > - if (ci->platdata->usb_phy)
> > + if (ci->platdata->phy)
> > + ci->phy = ci->platdata->phy;
> > + else if (ci->platdata->usb_phy)
> > ci->usb_phy = ci->platdata->usb_phy;
> > else
> > - ci->usb_phy = devm_usb_get_phy(dev, USB_PHY_TYPE_USB2);
> > + ci->phy = devm_phy_get(dev, "usb-phy");
> >
> > - if (IS_ERR(ci->usb_phy)) {
> > - ret = PTR_ERR(ci->usb_phy);
> > + if (IS_ERR(ci->phy) || (ci->phy == NULL && ci->usb_phy == NULL)) {
> > /*
> > * if -ENXIO is returned, it means PHY layer wasn't
> > * enabled, so it makes no sense to return -EPROBE_DEFER
> > * in that case, since no PHY driver will ever probe.
> > */
> > - if (ret == -ENXIO)
> > - return ret;
> > + if (PTR_ERR(ci->phy) == -ENXIO)
> > + return -ENXIO;
> >
> > - dev_err(dev, "no usb2 phy configured\n");
> > - return -EPROBE_DEFER;
> > + ci->usb_phy = devm_usb_get_phy(dev, USB_PHY_TYPE_USB2);
> > + if (IS_ERR(ci->usb_phy)) {
> > + dev_err(dev, "no usb2 phy configured\n");
> > + return -EPROBE_DEFER;
> > + }
> > }
>
> Sorry, I can't accept this change, why devm_usb_get_phy(dev, USB_PHY_TYPE_USB2)
> is put at error path? Since current get PHY operation is a little complicated,
> we may have a dedicate function to do it, dwc3 driver is a good example.

It's not the error path, it's the case when there is no PHY from the
generic PHY framework available. Getting an USB PHY is a fallback
solution.

I agree we can move this to a dedicated function. But even if doing so,
we'll have to test ci->phy first.

Or do you have something else in mind?

> > diff --git a/drivers/usb/chipidea/debug.c b/drivers/usb/chipidea/debug.c
> > index 5a7ea93011dd..999e9d683d7a 100644
> > --- a/drivers/usb/chipidea/debug.c
> > +++ b/drivers/usb/chipidea/debug.c
> > @@ -219,7 +219,8 @@ static int ci_otg_show(struct seq_file *s, void *unused)
> > fsm = &ci->fsm;
> >
> > /* ------ State ----- */
> > - usb_otg_state_string(ci->usb_phy->otg.state));
> > + seq_printf(s, "OTG state: %s\n\n",
> > + usb_otg_state_string(ci->otg.state));
>
> Again, rebase error?

Yes, sorry about that. This will be fixed in the next version of this
series.

Antoine

--
Antoine Ténart, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com
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