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nusb: workaround for endpoints with same index but different types

nusb code assumes endpoint numbers are unique.  It's true in general
case, but it becomes false once the direction bit is ignored.  The
commit adds a check so that two endpoints of different types are not
merged into one with Eboth direction.  It does overwrite endpoint
though, so it shouldn't be considered as a full fix.

--- a/sys/src/cmd/nusb/lib/parse.c

+++ b/sys/src/cmd/nusb/lib/parse.c

@@ -96,7 +96,7 @@

 static int

 parseendpt(Usbdev *d, Conf *c, Iface *ip, Altc *altc, uchar *b, int n, Ep **epp)

 {

-	int i, dir, epid;

+	int i, dir, epid, type;

 	Ep *ep;

 	DEp *dep;

@@ -115,17 +115,20 @@

 		dir = Ein;

 	else

 		dir = Eout;

+	type = dep->bmAttributes & 0x03;

 	ep = d->ep[epid];

 	if(ep == nil){

 		ep = mkep(d, epid);

 		ep->dir = dir;

-	}else if((ep->addr & 0x80) != (dep->bEndpointAddress & 0x80))

+	}else if((ep->addr & 0x80) != (dep->bEndpointAddress & 0x80) && ep->type == type)

 		ep->dir = Eboth;

+	else

+		ep->dir = dir;

 	ep->maxpkt = GET2(dep->wMaxPacketSize);

 	ep->ntds = 1 + ((ep->maxpkt >> 11) & 3);

 	ep->maxpkt &= 0x7FF;

 	ep->addr = dep->bEndpointAddress;

-	ep->type = dep->bmAttributes & 0x03;

+	ep->type = type;

 	ep->isotype = (dep->bmAttributes>>2) & 0x03;

 	ep->conf = c;

 	ep->iface = ip;