[SeaBIOS] K-TEK-M275TP-FN-BL-ML USB keyboard support

[Аладышев Константин]

Hello! I'm having problems with K-TEK-M275TP-FN-BL-ML keyboard
(http://www.key-tek.cn/Productview.asp?id=777). It is USB device with
keyboard and touchpad combined. It works in OS correctly, but doesn't work
in SeaBIOS.

I've tried to debug this issue and found that "usb_kbd_setup" function fails
on "(epdesc->wMaxPacketSize != 8)" check, cause "epdesc->wMaxPacketSize" is
actually 32. I've modified this "if" statement to pass 32 value also and now
function completes successfully. But it didn't help to solve my issue. There
are no interrupts from keyboard, "ehci_poll_intr" always returns -1 on
check:

if (token & QTD_STS_ACTIVE) {
        // No intrs found.
        return -1;
}

I don't know what to do now. What should  I check next?

Does SeaBIOS support USB keyboard+touchpad devices at all?