Hi,
I would like to port the following commit from 4.6 to older kernels.
1a85329171094951956a37acc8abb7e51c1e742e ("usb: gadget: composite:
Return bcdUSB 0x0310")
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=1a85329171094951956a37acc8abb7e51c1e742e
There is a some concern that revving the bcdUSB to 0x0310 will cause
problems for SuperSpeed devices based on older kernels that don't
otherwise have any USB 3.1 specific code.
On the device side I don't think there will be any problems because
there aren't really any checks against bcdUSB. We just set it to
0x0300 (0x0310 for kernel 4.6+) based on if the gadget tells us it
supports SuperSpeed or higher.
And I don't think there should be any problems for a host connecting
to these devices since any SuperSpeed capable host should know about
bcdUSB = 0x03XX. And I don't think the USB spec defines any different
functionality based solely on 0x0300 vs 0x0310.
The reason for this backport is that the USB CV tool now checks this
and ostensibly USB IF certification will require this for "new"
devices. So if you are basing a new device on a kernel older than 4.6,
it will not pass CV.
Any comments or recommendations or anything I missed?
Thanks,
John
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