staging: mmal-vchiq: Make timeout a defined parameter

The timeout period for VPU communications is a useful thing
to extend when debugging.
Set it via a define, rather than a magic number buried in the code.

Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.org>

drivers/staging/vc04_services/vchiq-mmal/mmal-vchiq.c

@@ -43,6 +43,12 @@ MODULE_VERSION("0.0.1");
  */
 #define VCHIQ_MMAL_MAX_COMPONENTS 64
 
+/*
+ * Timeout for synchronous msg responses in seconds.
+ * Helpful to increase this if stopping in the VPU debugger.
+ */
+#define SYNC_MSG_TIMEOUT	3
+
 /*#define FULL_MSG_DUMP 1*/
 
 #ifdef DEBUG
@@ -691,7 +697,7 @@ static int send_synchronous_mmal_msg(struct vchiq_mmal_instance *instance,
 	}
 
 	timeout = wait_for_completion_timeout(&msg_context->u.sync.cmplt,
-					      3 * HZ);
+					      SYNC_MSG_TIMEOUT * HZ);
 	if (timeout == 0) {
 		pr_err("timed out waiting for sync completion\n");
 		ret = -ETIME;