usb: wusbcore: change WA_SEGS_MAX to a legal value

commit f74b75e7 upstream.

change WA_SEGS_MAX to a number that is legal according to the WUSB
spec.
Signed-off-by: Thomas Pugliese <thomas.pugliese@gmail.com>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/wusbcore/wa-xfer.c

@@ -90,7 +90,8 @@
 #include "wusbhc.h"
 
 enum {
-	WA_SEGS_MAX = 255,
+	/* [WUSB] section 8.3.3 allocates 7 bits for the segment index. */
+	WA_SEGS_MAX = 128,
 };
 
 enum wa_seg_status {
@@ -444,7 +445,7 @@ static ssize_t __wa_xfer_setup_sizes(struct wa_xfer *xfer,
 	xfer->seg_size = (xfer->seg_size / maxpktsize) * maxpktsize;
 	xfer->segs = (urb->transfer_buffer_length + xfer->seg_size - 1)
 		/ xfer->seg_size;
-	if (xfer->segs >= WA_SEGS_MAX) {
+	if (xfer->segs > WA_SEGS_MAX) {
 		dev_err(dev, "BUG? ops, number of segments %d bigger than %d\n",
 			(int)(urb->transfer_buffer_length / xfer->seg_size),
 			WA_SEGS_MAX);