Re: [new-usb] - USB_ERR_NO_POWER on keyboard hub

On Mon, May 18, 2009 at 10:46 AM, Hans Petter Selasky <hselasky_at_c2i.net> wrote:
> On Monday 18 May 2009, Renato Botelho wrote:
>> I have a Sun USB Type 7 keyboard, and this keyboard has an USB hub
>> with 3 ports on it. I'm using one of those 3 ports to plug the mouse and
>> it's working fine.
>>
>> uhub5: 4 ports with 3 removable, bus powered
>> ugen0.3: <Alcor Micro> at usbus0
>> ums0: <Alcor Micro USB Mouse, class 0/0, rev 1.10/51.27, addr 3> on usbus0
>> ums0: 3 buttons and [XYZ] coordinates ID=0
>> ugen0.4: <Sun Microsystems> at usbus0
>> ukbd0: <Sun Microsystems Type 7 USB keyboard, class 0/0, rev
>> 2.00/1.04, addr 4> on usbus0
>> kbd2 at ukbd0
>>
>> When I tried to plug a pen drive on anothe one, I got this:
>>
>> usb2_set_config_index:531: power exceeded 500 > 100
>> usb2_set_config_index:531: power exceeded 500 > 100
>> usb2_alloc_device:1755: Failure selecting configuration index 0:
>> USB_ERR_NO_POWER, port 2, addr 5 (ignored)
>> ugen0.5: <ALi Corp.> at usbus0
>> pid 3705 (hald-probe-usb2-dev), uid 0: exited on signal 11
>> ugen0.5: <ALi Corp.> at usbus0 (disconnected)
>>
>> usb2_set_config_index:531: power exceeded 500 > 100
>> usb2_set_config_index:531: power exceeded 500 > 100
>> usb2_alloc_device:1755: Failure selecting configuration index 0:
>> USB_ERR_NO_POWER, port 1, addr 5 (ignored)
>> ugen0.5: <ALi Corp.> at usbus0
>> pid 3886 (hald-probe-usb2-dev), uid 0: exited on signal 11
>> ugen0.5: <ALi Corp.> at usbus0 (disconnected)
>>
>> I'm using FreeBSD 8.0-current r192140.
>>
>> Let me know if there is more information i need to provide.
>>
>> Thanks
>
> Hi,
>
> Your Keyboard HUB technically does not allow current consumption above 100mA
> per port. Your memstick reports it needs 500mA. Probably you can hack around
> it, but then your hardware might break ...

Yep, I found now this text on Sun FAQ:

What is power budget control?

Power budget control is specified in USB spec to limit device
connections to a hub to avoid overcurrent condition. A self-powered
hub can supply a maximum of 500mA to each port, while a bus-powered
hub should only supply a maximum of 100mA to each port. With power
budget control, devices consuming power more than 100mA will be denied
connection to a bus-powered hub. And two bus-powered hubs are not
allowed to be concatenated.

I can live without it, prefer to keep my kbd working :)

Thank you
-- 
Renato Botelho