Sorry if this is the wrong place for this question - the device is part of a family of products we sell and only intended to be used with our other product (running linux). The reason we can't change the firmware is we have already sold the product and it worked fine with our old kernel (2.6.35.13) but no longer works with our updated kernel (3.14.39). Thanks, Todd On Wed, Sep 16, 2015 at 3:34 PM, Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx> wrote: > On Wed, Sep 16, 2015 at 02:18:23PM -0700, Todd Efflam wrote: >> Hello, >> We have an issue where we cannot communicate with an old device with a >> wMaxPacketSize set to 0xFFFF. It is visible using lsusb -v and shows >> the correct max packte size, but is not listed in lsusb -t. The >> dmesg output gives us "usb 2-2.1: Not enough bandwidth for new device >> state. " and this comes from xhci (in particular xhci.c in the >> xhci_configure_endpoint_result function). When we set the max packet >> size on the device to something more reasonable (i.e. a0) the errors >> go away and we are able to communicate with it. >> >> We would like to patch the xhci host driver to change any FFFF max >> packet sizes to a0, but are having trouble finding where exactly to do >> so. We've identified the function xhci_urb_enqueue as a possible >> point, but printing out the max packet sizes (hw_max_packet_size and >> max_packet_size) only shows sizes of 8. Unfortunately, changing the >> configuration on the device itself is not an option. Any advice would >> be appreciated! > > Can't you just fix the firmware on the broken device? I can't imagine > it works on other operating systems properly as-is. > > thanks, > > greg k-h -- 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
