USB: make transfer_buffer_lengths in struct urb field u32

Roel Kluin pointed out that transfer_buffer_lengths in struct urb was
declared as an 'int'.  This patch changes this field to be 'u32' to
prevent any potential negative conversion and comparison errors.

This triggered a few compiler warning messages when these fields were
being used with the min macro, so they have also been fixed up in this
patch.

Cc: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/usb/host/isp116x-hcd.c

@@ -772,7 +772,7 @@ static int isp116x_urb_enqueue(struct usb_hcd *hcd,
 		break;
 	case PIPE_INTERRUPT:
 		urb->interval = ep->period;
-		ep->length = min((int)ep->maxpacket,
+		ep->length = min_t(u32, ep->maxpacket,
 				 urb->transfer_buffer_length);
 
 		/* urb submitted for already existing endpoint */

drivers/usb/host/r8a66597-hcd.c

@@ -1394,7 +1394,7 @@ static void packet_write(struct r8a66597 *r8a66597, u16 pipenum)
 			   (int)urb->iso_frame_desc[td->iso_cnt].length);
 	} else {
 		buf = (u16 *)(urb->transfer_buffer + urb->actual_length);
-		size = min((int)bufsize,
+		size = min_t(u32, bufsize,
 			   urb->transfer_buffer_length - urb->actual_length);
 	}
 

drivers/usb/host/sl811-hcd.c

@@ -230,7 +230,7 @@ static void in_packet(
 	writeb(usb_pipedevice(urb->pipe), data_reg);
 
 	sl811_write(sl811, bank + SL11H_HOSTCTLREG, control);
-	ep->length = min((int)len,
+	ep->length = min_t(u32, len,
 			urb->transfer_buffer_length - urb->actual_length);
 	PACKET("IN%s/%d qh%p len%d\n", ep->nak_count ? "/retry" : "",
 			!!usb_gettoggle(urb->dev, ep->epnum, 0), ep, len);
@@ -255,7 +255,7 @@ static void out_packet(
 	buf = urb->transfer_buffer + urb->actual_length;
 	prefetch(buf);
 
-	len = min((int)ep->maxpacket,
+	len = min_t(u32, ep->maxpacket,
 			urb->transfer_buffer_length - urb->actual_length);
 
 	if (!(control & SL11H_HCTLMASK_ISOCH)