Re: [PATCH] usb: chipidea: Grab the (legacy) USB PHY by phandle first

From: Paul Kocialkowski
Date: Wed Jan 16 2019 - 09:22:44 EST


Hi,

On Wed, 2019-01-16 at 14:44 +0100, Thomas Petazzoni wrote:
> Well prior to your code, there was already a possibility for both
> ci->phy and ci->usb_phy to be valid. I don't think it's really useful
> to avoid the fallback when a generic PHY has already been found, it's
> confusing. If really you want to clarify that, it should be:
>
> /* Let's first try to find a generic PHY */
> ci->phy = devm_phy_get(dev->parent, "usb-phy");
> if (IS_ERR(ci->phy)) {
> /* Fall back to legacy USB PHY */
> ci->usb_phy = devm_usb_get_phy_by_phandle(dev->parent, "phys", 0);
> if (IS_ERR(ci->usb_phy))
> ci->usb_phy = devm_usb_get_phy(dev->parent, USB_PHY_TYPE_USB2);
> }
>
> With that, you would only have either ci->phy or ci->usb_phy be valid,
> and never both. With your change, you can have ci->phy and ci->usb_phy
> both be valid if the legacy USB PHY was found using
> devm_usb_get_phy_by_phandle(), but not if we fell back to
> devm_usb_get_phy().

Okay that makes sense, your suggestion is indeed more consistent with
the existing behavior. I'll go with that in the next revision!

Cheers,

Paul

--
Paul Kocialkowski, Bootlin
Embedded Linux and kernel engineering
https://bootlin.com