usb: dwc3: ep0: Handle requests greater than wMaxPacketSize

To allow ep0 out transfers of upto bounce buffer size
instead of maxpacketsize, use the transfer size as multiple
of ep0 maxpacket size.

Cc: stable@vger.kernel.org
Signed-off-by: Moiz Sonasath <m-sonasath@ti.com>
Signed-off-by: Partha Basak <p-basak2@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
diff --git a/drivers/usb/dwc3/ep0.c b/drivers/usb/dwc3/ep0.c
index 25910e2..a40d3bb 100644
--- a/drivers/usb/dwc3/ep0.c
+++ b/drivers/usb/dwc3/ep0.c
@@ -559,8 +559,12 @@
 	length = trb->size & DWC3_TRB_SIZE_MASK;
 
 	if (dwc->ep0_bounced) {
+		unsigned transfer_size = ur->length;
+		unsigned maxp = ep0->endpoint.maxpacket;
+
+		transfer_size += (maxp - (transfer_size % maxp));
 		transferred = min_t(u32, ur->length,
-				ep0->endpoint.maxpacket - length);
+				transfer_size - length);
 		memcpy(ur->buf, dwc->ep0_bounce, transferred);
 		dwc->ep0_bounced = false;
 	} else {