[PATCH] Atmel USB High speed device port, speed fix

Douglas Gilbert dgilbert at interlog.com
Sat Nov 14 16:02:54 PST 2015

Following changes that appeared in lk 4.0.0, the gadget udc driver for
some ARM based Atmel SoCs (e.g. at91sam9x5 and sama5d3 families)
incorrectly deduced full-speed USB link speed even when the hardware
had negotiated a high-speed link. The fix is to make sure that the
UDPHS Interrupt Enable Register value does not mask the SPEED bit
in the Interrupt Status Register.

For a mass storage gadget this problem lead to failures when the host
had a USB 3 port with the xhci_hcd driver. If the host was a USB 2
port using the ehci_hcd driver then the mass storage gadget worked
(but probably at a lower speed than it should have).

Signed-of-by: Douglas Gilbert <dgilbert at interlog.com>
Cc: <stable at vger.kernel.org> #4.0+
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