USB support for device tree

[Grant Likely]

On Fri, Nov 4, 2011 at 4:25 AM, Pavan Kondeti <pkondeti at codeaurora.org> wrote:
> Hi
>
> I am working on adding USB device tree support for MSM platform.  One of
> our chip set has 2 hsusb cores. The first core is configured as otg and
> the other core is configured in host only mode (EHCI compliant). Are the
> below device node names Okay? Please suggest.
>
> hsusb0-otg: usb at 0xa6000000 {
>        compatible = "qcom,hsusb-otg";
>        ---
> };
>
> hsusb0-device: usb at 0xa6000000 {
>        compatible = "qcom,hsusb-device";
>        ---
> };
>
> hsusb0-host: usb at 0xa6000000 {
>        compatible = "qcom,hsusb-host", "usb-ehci";
>        ---
> };
>
> hsusb1-host: usb at 0xa6000000 {
>        compatible = "qcom,hsusb-host", "usb-ehci";
>        ---
> };
>
> /* super speed support
>
> ssusb0-device: usb at 0xa6000000 {
>        compatible = "qcom,ssusb-device";
> };


The host controller node names as "usb@<adddr>" as you have here is
exactly right.  The driver doesn't care and will only look at the
compatible list.  OTG controllers can also use "usb@" as the prefix.

Controllers that are only in device mode should probably be called
something like "usb-gadget@<addr>" or similar, because "usb@" is used
for host controllers.

The label names (hsusb*-host, hsusb*-device) are completely irrelevant
since Linux never sees them.  Use whatever you want for the label
names.

Also, the form of the node name is: "usb at a6000000" (without '0x' in
the address).

g.