On Tue, May 12, 2009 at 09:55:08AM +0200, Clemens Ladisch wrote: > David Fries wrote: > > usb_submit_urb returns -22 EINVAL invalid argument as it is trying to > > submit an interrupt packet to what is registered as an isoc endpoint. > > The second interface has the same end point addresses as the first. > > Any suggestions on how to deal with this class of broken hardware? > > > > I:* If#= 0 Alt= 0 ... > > E: Ad=81(I) Atr=03(Int.) MxPS= 4 Ivl=1ms > > I:* If#= 1 Alt= 0 ... > > E: Ad=81(I) Atr=01(Isoc) MxPS= 4 Ivl=1ms > > AFAICS the USB core memorizes the descriptor belonging to a specific > endpoint number whenever usb_set_interface() is called. In this case, > the second interface is initialized later, so the second set of > descriptors wins. > > The driver could call usb_set_interface() again for the first interface > so that the USB core takes notice of the first set of endpoints again. > Please try the patch below. > > I guess I'll have to write another quirk for this. Thanks for the quick response, sorry for taking so long to test it. Adding usb_set_interface lets the device work again, I had been tracking this down for a while, I'm glad you knew what to do. The MOTU Fastlane device is the only one using QUIRK_MIDI_RAW. How about changing the name to QUIRK_MIDI_FASTLANE to imply it isn't completely generic anymore and adding a comment? I can write up that patch if it's agreeable. The only danger I see is if there are some MOTU Fastlane devices with a corrected descriptor record, but if that were the case setting it to the 0 alternative setting would be a no-op in that case, so it sounds good to me. case QUIRK_MIDI_FASTLANE: /* MOTU Fastlane has two interfaces with the second * interface reusing the endpoint addresses voilating * the standard. Select interface 0 again to reload * that configuration. */ usb_set_interface(umidi->chip->dev, 0, 0); umidi->usb_protocol_ops = &snd_usbmidi_raw_ops; err = snd_usbmidi_detect_per_port_endpoints(umidi, endpoints); break; > --- linux/sound/usb/usbmidi.c > +++ linux/sound/usb/usbmidi.c > @@ -1779,6 +1779,7 @@ > err = snd_usbmidi_detect_per_port_endpoints(umidi, endpoints); > break; > case QUIRK_MIDI_RAW: > + usb_set_interface(umidi->chip->dev, 0, 0); > umidi->usb_protocol_ops = &snd_usbmidi_raw_ops; > err = snd_usbmidi_detect_per_port_endpoints(umidi, endpoints); > break; > -- > 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 -- David Fries <david@xxxxxxxxx> http://fries.net/~david/ (PGP encryption key available) -- 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
