fsl_usb2_udc: Add a wmb before priming endpoint.

Add a wmb to fsl_queue_td before priming the endpoint. This ensures that the modifications to the QH are seen by the hardware. Added comment as suggested by Felipe Balbi. Signed-off-by: Will Newton <[email protected]> Acked-by: Li Yang <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
mgowda · Oct 17, 2008 · 59097fb · 59097fb
1 parent 224b503
commit 59097fb
Showing 1 changed file with 3 additions and 0 deletions.
diff --git a/drivers/usb/gadget/fsl_usb2_udc.c b/drivers/usb/gadget/fsl_usb2_udc.c
@@ -643,6 +643,9 @@ static void fsl_queue_td(struct fsl_ep *ep, struct fsl_req *req)
 			| EP_QUEUE_HEAD_STATUS_HALT));
 	dQH->size_ioc_int_sts &= temp;
 
+	/* Ensure that updates to the QH will occure before priming. */
+	wmb();
+
 	/* Prime endpoint by writing 1 to ENDPTPRIME */
 	temp = ep_is_in(ep)
 		? (1 << (ep_index(ep) + 16))