usb: xhci: bInterval quirk for TI TUSB73x0

commit 69307ccb

 upstream.

As per [1] issue #4,
"The periodic EP scheduler always tries to schedule the EPs
that have large intervals (interval equal to or greater than
128 microframes) into different microframes. So it maintains
an internal counter and increments for each large interval
EP added. When the counter is greater than 128, the scheduler
rejects the new EP. So when the hub re-enumerated 128 times,
it triggers this condition."

This results in Bandwidth error when devices with periodic
endpoints (ISO/INT) having bInterval > 7 are plugged and
unplugged several times on a TUSB73x0 XHCI host.

Workaround this issue by limiting the bInterval to 7
(i.e. interval to 6) for High-speed or faster periodic endpoints.

[1] - http://www.ti.com/lit/er/sllz076/sllz076.pdf

Signed-off-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>