Questions about USB, uhid, ukbd and quirks

[Niclas Zeising]

On 11/24/12 14:19, Hans Petter Selasky wrote:
> On Saturday 24 November 2012 13:54:45 Niclas Zeising wrote:
>> On 11/24/12 13:23, Niclas Zeising wrote:
>>> On 11/24/12 13:17, Hans Petter Selasky wrote:
>>>> On Saturday 24 November 2012 12:13:49 Hans Petter Selasky wrote:
>>>>> On Saturday 24 November 2012 00:00:44 Niclas Zeising wrote:
>>>>>> Hi!
>>>>>> I have a couple of questions about USB.
>>>>>> I recently bought a new USB keyboard, a Logitech K120. When attaching
>>>>>> this to a FreeBSD system, however, it is detected as a hid device
>>>>>> (attaching to uhid) rather than a keyboard (attaching to ukbd). The
>>>>>> keyboard works fine, but I'm just curious as to why it doesn't use
>>>>>> ukbd.
>>>>>
>>>>>> The output from usbconfig for this keyboard is:
>>>>> Hi,
>>>>>
>>>>> It seems the UHID driver needs to be synced with UMS and UKBD
>>>>> regarding the
>>>>> detection logic. Can you try the attached patch and report back.
>>>>>
>>>>> --HPS
>>>>
>>>> One more thing to check:
>>>>
>>>> /etc/devd/usb.conf
>>>>
>>>> Is perhaps auto-loading uhid before ukbd, and that might also be part
>>>> of the
>>>> issue.
>>>
>>> Hi!
>>> Having ukbd in the kernel, and not uhid, makes uhid load as a module
>>> during boot and attach to the keyboard, even with your patch. I'm
>>> recompiling the kernel now with uhid as part of the kernel to see if it
>>> makes a difference. I'm not too confortable hacking /etc/devd/usb.conf,
>>> but if you can point me in the right direction I'll have a go at it.
>>> Regards!
>>
>> Having uhid in the kernel did not make a difference, it attached to the
>> keyboard (or rather, the keyboard attached to the uhid driver, I guess).
>> Regards!
>
> Could you dump the configuration descriptor of your device using usbconfig?
>
> usbconfig -d X.Y dump_curr_config_desc
>
> --HPS

Attached patch contains the dump.  From my reading of the USB spec, it 
seems that this keyboard has two interfaces, one that detects as a 
keyboard, and might be the boot device, and one that's just a regular 
hid.  I might also be very wrong in this. :)
I have a dump from a keyboard that only attaches to ukbd, if you need 
something to compare to.  That keyboard, however, believes it's a liteon 
keyboard, rather than a logitech keyboard.  That, however, is probably 
Logitech's fault.
Thank you for helping out!
Regards!
-- 
Niclas
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