Applying Patch to Change Max Packet Size for Device

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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!

Thanks,
Todd
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