On Wed, Mar 28, 2012 at 11:28:46PM +0200, Peter Stuge wrote: > Sarah Sharp wrote: > > Here is the other mail I was referring to in the thread with shashank. > > > > Alan, perhaps there's a change from 2.6.38 to 3.0 that makes the USB > > core request a string descriptor that the USB devices don't like? > > > > On Tue, Mar 27, 2012 at 08:23:03PM +0530, Aditya Mittal wrote: > > > We see a request for string descriptor 238 (0xEE) which is a microsoft > > > specific descriptor with kernel 3.0.0 whereas we do not see a request for > > > this string descriptor for version 2.6.38. > > Interesting. The 0xee string is indeed a Microsoft USB extension. It > can be used to tell Windows what driver it should use for the device. > Works really well out of the box on Windows 8 and later. > > I'm also surprised if Linux is sending that. I'm not saying that it's > wrong, just surprised. In any case, any device *must* be able to deal > with a request for a string descriptor which doesn't exist. > > This is clearly a problem in the device, regardless of where the 0xee > request is coming from. (Wild guess: virtual machine someone forgot > was still running?) Windows XPSP1 and later ask exactly once for the > string descriptor, for every device that hasn't been seen before. AFAIK the 0xee is not sent by Linux kernel, it is sent by mtp-probe (part of libmtp, media transfer protocol) which is run via udev rule. I'm not sure why there is a difference between Linux 3.0.0 and 2.6.38? Johannes -- 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
