diff --git a/drivers/net/can/flexcan.c b/drivers/net/can/flexcan.c
index 630c7bf032a8095435e82ed5bf499a8bfb78c122..76dcbca6c80cdfd20967a9eae9c6acc75a797427 100644
--- a/drivers/net/can/flexcan.c
+++ b/drivers/net/can/flexcan.c
@@ -136,6 +136,17 @@
 
 /* FLEXCAN message buffers */
 #define FLEXCAN_MB_CNT_CODE(x)		(((x) & 0xf) << 24)
+#define FLEXCAN_MB_CODE_RX_INACTIVE	(0x0 << 24)
+#define FLEXCAN_MB_CODE_RX_EMPTY	(0x4 << 24)
+#define FLEXCAN_MB_CODE_RX_FULL		(0x2 << 24)
+#define FLEXCAN_MB_CODE_RX_OVERRRUN	(0x6 << 24)
+#define FLEXCAN_MB_CODE_RX_RANSWER	(0xa << 24)
+
+#define FLEXCAN_MB_CODE_TX_INACTIVE	(0x8 << 24)
+#define FLEXCAN_MB_CODE_TX_ABORT	(0x9 << 24)
+#define FLEXCAN_MB_CODE_TX_DATA		(0xc << 24)
+#define FLEXCAN_MB_CODE_TX_TANSWER	(0xe << 24)
+
 #define FLEXCAN_MB_CNT_SRR		BIT(22)
 #define FLEXCAN_MB_CNT_IDE		BIT(21)
 #define FLEXCAN_MB_CNT_RTR		BIT(20)
@@ -867,8 +878,8 @@ static int flexcan_chip_start(struct net_device *dev)
 	netdev_dbg(dev, "%s: writing ctrl=0x%08x", __func__, reg_ctrl);
 	flexcan_write(reg_ctrl, &regs->ctrl);
 
-	/* Abort any pending TX, mark Mailbox as INACTIVE */
-	flexcan_write(FLEXCAN_MB_CNT_CODE(0x4),
+	/* mark TX mailbox as INACTIVE */
+	flexcan_write(FLEXCAN_MB_CODE_TX_INACTIVE,
 		      &regs->cantxfg[FLEXCAN_TX_BUF_ID].can_ctrl);
 
 	/* acceptance mask/acceptance code (accept everything) */