[PATCH] totally untested attachment of device nodes to usb devices

[Thomas Abraham]

On 6 November 2011 22:28, Grant Likely <grant.likely at secretlab.ca> wrote:
> On Sun, Nov 6, 2011 at 3:09 AM, Thomas Abraham
> <thomas.abraham at linaro.org> wrote:
>> Hi Grant,
>>
>> On 5 November 2011 00:50, Grant Likely <grant.likely at secretlab.ca> wrote:
>>> Proof of concept, needs to be made compilable and add the unwind path
>>> on error and remove.
>>>
>>> Bodged-together-by: Grant Likely <grant.likely at secretlab.ca>
>>
>> Is there is reason to include device nodes in dts file for usb devices
>> that are attached to a usb host? What additional information would
>> such nodes include apart from the device information obtained during
>> enumeration?
>
> There are cases where soldered down USB devices on the mainboard will
> have additional connections that cannot be discovered by the driver.
> GPIOs for instance, or an Ethernet device that needs to be assigned a
> MAC address.

Thanks Grant. Does that imply that there has to be additional code in
other places which will actually use the information available in the
attached device node. In the example of MAC address for ethernet
device, the logic to lookup and use the MAC address might have to be
added to cdc/rndis layers.

Also, would the matching of device node on 'udev->portnum' be
consistent each time. There could different devices connected at boot
time to the host port or there could be no devices connected. To
ensure that udev->portnum matches each time, there might have to be
additional restrictions on the hub port to which the soldered USB
devices are connected.

Thanks,
Thomas.

>
> g.
>