I'm seeing a problem booting from USB thumbdrives with commit ab9d771ce
ehci: Update usb command timeouts to use usb_xfer_time()

I'm not quite sure what the problem is other than it not liking the new timeouts.

I couldn't see any problems with the ehci_control() calls to ehci_wait_td().

But the ehci_send_bulk() only allows the system to boot if I change
int ret = ehci_wait_td(pipe, td, end);
to
int ret = ehci_wait_td(pipe, td, timer_calc(5000));

One potential problem is that the "end" value is calculated once and reused

multiple times in the functions. Prior to the commit the timeout value was passed
to the ehci_wait_td() function. Now the final "end" time is passed. So it looks like

once the end timeout is reached in one of the loops that calls ehci_wait_td() the

timer will always be expired for any other calls from that function.

One solution might be to get rid of the "end" variable and change the calls from
ret = ehci_wait_td(pipe, td, end);
to
ret = ehci_wait_td(pipe, td, timer_calc(usb_xfer_time(p, datasize)));

Making the above change didn't have any impact on my booting problem until

I forced the ehci_send_bulk() timeouts to 5000.

Thanks in advance for any advice anyone can offer,
Dave