can: at91_can: let get_tx_* functions return unsigned int

Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
diff --git a/drivers/net/can/at91_can.c b/drivers/net/can/at91_can.c
index 5358d70..716f22b 100644
--- a/drivers/net/can/at91_can.c
+++ b/drivers/net/can/at91_can.c
@@ -186,17 +186,17 @@
 	.brp_inc	= 1,
 };
 
-static inline int get_tx_next_mb(const struct at91_priv *priv)
+static inline unsigned int get_tx_next_mb(const struct at91_priv *priv)
 {
 	return (priv->tx_next & AT91_NEXT_MB_MASK) + AT91_MB_TX_FIRST;
 }
 
-static inline int get_tx_next_prio(const struct at91_priv *priv)
+static inline unsigned int get_tx_next_prio(const struct at91_priv *priv)
 {
 	return (priv->tx_next >> AT91_NEXT_PRIO_SHIFT) & 0xf;
 }
 
-static inline int get_tx_echo_mb(const struct at91_priv *priv)
+static inline unsigned int get_tx_echo_mb(const struct at91_priv *priv)
 {
 	return (priv->tx_echo & AT91_NEXT_MB_MASK) + AT91_MB_TX_FIRST;
 }