Re: [PATCH v2 37/52] dt-bindings: usb: dwc3: Fix usb-phy check

Felipe Balbi
2021-09-01T12:40:24Z

Maxime Ripard <maxime@cerno.tech> writes:

> The original binding was allowing any combination of usb2-phy and
> usb3-phy in the phys and phy-names properties.
>
> However, the current binding enforces that those properties must be a
> list of usb2-phy and usb3-phy, with exactly one element, effectively
> making usb2-phy the only value being valid.
>
> Let's rework the properties description to allow either one or two
> element picked with values either usb2-phy or usb3-phy. The rest of the
> tooling makes sure that we don't get any duplicate value, so this should
> be what we want.
>
> Cc: Felipe Balbi <balbi@kernel.org>
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Cc: linux-usb@vger.kernel.org
> Signed-off-by: Maxime Ripard <maxime@cerno.tech>
> ---
> Documentation/devicetree/bindings/usb/snps,dwc3.yaml | 10 +++++-----
> 1 file changed, 5 insertions(+), 5 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/usb/snps,dwc3.yaml b/Documentation/devicetree/bindings/usb/snps,dwc3.yaml
> index 078fb7889593..c1c970073681 100644
> --- a/Documentation/devicetree/bindings/usb/snps,dwc3.yaml
> +++ b/Documentation/devicetree/bindings/usb/snps,dwc3.yaml
> @@ -73,15 +73,15 @@ properties:
>
> phys:
> minItems: 1
> - items:
> - - description: USB2/HS PHY
> - - description: USB3/SS PHY
> + maxItems: 2

I'm not sure you should enforce a maximum of 2 PHYs. Some systems may
use more than one USB2 PHY to take care of different parts of the USB
link.

IIRC N900 was a USB2-only system which shipped with two USB2 PHYs: one
handling the communication proper and one handling charger detection and
the like.

--
balbi