> >>>> > >>>> Thank you, that sounds like the best approach. > >>>> In this case I think perhaps the long wait without any data is an > >>>> problem with the imx6 Chipidea USB controller. > >>> > >>> What's the possible problem? > >> > >> Sorry for the delay in replying, I have been getting some more > >> details with a USB Analyser. > >> > >> The scenario is that the NCM device is enumerating so we see the > messages to: > >> > >> SetAddress (1) > >> GetDescriptor (Device) > >> GetDescriptor (StringN) > >> GetDescriptor (Configuration) > >> SetConfiguration (1) > >> GetDescriptor (String iInterface) > >> GetDescriptor (String iInterface) > >> > >> At this point the NCM host sends Writes to the F_FS EP0 but for some > >> reason the host device does not respond and only issues SOF packets > >> for hours. This happens occasionally and is fixed by turning the device off > and on again. > >> > >> > > > > We may find this 'some reason', is it device error or host error? > > > > Do you have below patch in your code: > > > > commit 953c66469735aed8d2ada639a72b150f01dae605 > > Author: Abbas Raza <Abbas_Raza@xxxxxxxxxx> > > Date: Thu Jul 17 19:34:31 2014 +0800 > > > > usb: chipidea: udc: Disable auto ZLP generation on ep0 > > > > There are 2 methods for ZLP (zero-length packet) generation: > > 1) In software > > 2) Automatic generation by device controller > > > > 1) is implemented in UDC driver and it attaches ZLP to IN packet if > > descriptor->size < wLength > > 2) can be enabled/disabled by setting ZLT bit in the QH > > > > Peter > > Yes I have that patch, could that be a problem? > No, you need that patch. Get to know which side has problem first. Peter > Jim > > > > >> Unless I am mistaken from a NCM gadget point of view the attached > >> device is working correctly and there is no way to know it has failed, is that > correct? > >> > >>> > >>>> > >>>> I guess it should suspend and drop the connections if there is no > >>>> traffic for more than 10ms? > >>>> > >>> > >>> If the Device side NAK host's IN/OUT token continually, the pipe > >>> will not be stopped, the host will send token continually until the > >>> application cancel this request. > >>> -- 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
