Re: OTG - Powered hub and mouse

[Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>]

On Wed, 21 Mar 2012, Pham Ngoc Hai wrote:

> Hi, 
> 
> I have a Samsung galaxy S2 with an OTG cable, I have disable all the white-list features of the kernel. Now 
> when I connect the slow USB� mouse to the OTG cable, the phone can 
> detect the mouse and I can use the mouse, but if I connect a powered hub to� the OTG cable and then connect the mouse to the hub, the phone cannot detect the mouse anymore.
> 
> Phone - OTG cable - Mouse�� < works� (1)
> 
> Phone - OTG cable - USB2.0 Thumb Driver � < works
> 
> Phone - OTG cable - USB2.0 Powered hub -� Mouse� < DOES NOT work (2)
> 
> Phone - OTG cable - USB2.0 Powered hub -� USB2.0 Thumb Driver < works

Judging by the logs you provided, it looks like your hub doesn't work 
well with low-speed devices.  Or maybe it just doesn't work with that 
particular mouse.

Try a different brand of hub.

Incidentally, all those lines like

> e263d180 2427795268 C Ii:2:002:1 0:2048 1 = 10
> e263d180 2427795275 S Ii:2:002:1 -115:2048 1 <

in your log indicate there's a bug somewhere on your system.  Maybe in 
the host controller driver or maybe in the hub's descriptors.  What 
does "lsusb -v" show?

Alan Stern

--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html