From a4aa0204601a59df7ce5c9c0c7f6535452a50ee0 Mon Sep 17 00:00:00 2001
From: Collin Kidder <collink@kkmfg.com>
Date: Mon, 12 Aug 2013 08:45:13 -0400
Subject: [PATCH] Disable interrupt for MB if there are no frames to send

This patch was suggested by bodynek and fixes a problem where too many interrupts will trigger for no reason.
---
 due_can.cpp | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/due_can.cpp b/due_can.cpp
index 8b2fee7..8ca40e2 100644
--- a/due_can.cpp
+++ b/due_can.cpp
@@ -871,6 +871,9 @@ void CANRaw::mailbox_int_handler(uint8_t mb, uint32_t ul_status) {
 				global_send_transfer_cmd((0x1u << mb));
 				tx_buffer_head = (tx_buffer_head + 1) % SIZE_TX_BUFFER;
 			}
+			else {
+				disable_interrupt(0x01 << mb);
+			}
 			break;
 		case 5: //producer - technically still a transmit buffer
 			break;