Re: [PATCH v10 6/9] dt-bindings: usb: Add NVIDIA Tegra XUSB controller binding

From: Stephen Warren
Date: Wed Mar 16 2016 - 14:08:15 EST

On 03/04/2016 09:19 AM, Thierry Reding wrote:
From: Thierry Reding <treding@xxxxxxxxxx>

Add device-tree binding documentation for the XUSB controller present
on Tegra124 and later SoCs. This controller supports USB 3.0 via an xHCI
compliant interface.

Based on work by Andrew Bresticker <abrestic@xxxxxxxxxxxx>.

diff --git a/Documentation/devicetree/bindings/usb/nvidia,tegra124-xusb.txt b/Documentation/devicetree/bindings/usb/nvidia,tegra124-xusb.txt

+Required properties:

+- nvidia,xusb-padctl: phandle to the XUSB pad controller that is used to
+ configure the USB pads used by the XHCI controller

Is "global" access to the PADCTL DT node/driver required? I rather would have expected this binding to reference the port objects in the PADCTL node. Perhaps the intent is that drivers can use this property to go and read the port information directly from the PADCTL node and interpret it themselves without requiring the PADCTL driver to provide an interface for ports? I guess that would also explain why this binding references only PHYs and not ports:

+Optional properties:
+- phys: Must contain an entry for each entry in phy-names.
+ See ../phy/phy-bindings.txt for details.
+- phy-names: Should include an entry for each PHY used by the controller. The
+ following PHYs are available:
+ - Tegra124: usb2-0, usb2-1, usb2-2, hsic-0, hsic-1, usb3-0, usb3-1
+ - Tegra132: usb2-0, usb2-1, usb2-2, hsic-0, hsic-1, usb3-0, usb3-1

If that's how this works (which might be worth mentioning in the binding doc), then:
Acked-by: Stephen Warren <swarren@xxxxxxxxxx>