diff --git a/drivers/tty/serial/mpc52xx_uart.c b/drivers/tty/serial/mpc52xx_uart.c
index 8a6958377764..3acc0f185762 100644
--- a/drivers/tty/serial/mpc52xx_uart.c
+++ b/drivers/tty/serial/mpc52xx_uart.c
@@ -436,31 +436,31 @@ static void mpc512x_psc_fifo_init(struct uart_port *port)
 	out_be32(&FIFO_512x(port)->rximr, MPC512x_PSC_FIFO_ALARM);
 }
 
-static int mpc512x_psc_raw_rx_rdy(struct uart_port *port)
+static unsigned int mpc512x_psc_raw_rx_rdy(struct uart_port *port)
 {
 	return !(in_be32(&FIFO_512x(port)->rxsr) & MPC512x_PSC_FIFO_EMPTY);
 }
 
-static int mpc512x_psc_raw_tx_rdy(struct uart_port *port)
+static unsigned int mpc512x_psc_raw_tx_rdy(struct uart_port *port)
 {
 	return !(in_be32(&FIFO_512x(port)->txsr) & MPC512x_PSC_FIFO_FULL);
 }
 
-static int mpc512x_psc_rx_rdy(struct uart_port *port)
+static unsigned int mpc512x_psc_rx_rdy(struct uart_port *port)
 {
 	return in_be32(&FIFO_512x(port)->rxsr)
 	    & in_be32(&FIFO_512x(port)->rximr)
 	    & MPC512x_PSC_FIFO_ALARM;
 }
 
-static int mpc512x_psc_tx_rdy(struct uart_port *port)
+static unsigned int mpc512x_psc_tx_rdy(struct uart_port *port)
 {
 	return in_be32(&FIFO_512x(port)->txsr)
 	    & in_be32(&FIFO_512x(port)->tximr)
 	    & MPC512x_PSC_FIFO_ALARM;
 }
 
-static int mpc512x_psc_tx_empty(struct uart_port *port)
+static unsigned int mpc512x_psc_tx_empty(struct uart_port *port)
 {
 	return in_be32(&FIFO_512x(port)->txsr)
 	    & MPC512x_PSC_FIFO_EMPTY;
@@ -780,29 +780,29 @@ static void mpc5125_psc_fifo_init(struct uart_port *port)
 	out_be32(&FIFO_5125(port)->rximr, MPC512x_PSC_FIFO_ALARM);
 }
 
-static int mpc5125_psc_raw_rx_rdy(struct uart_port *port)
+static unsigned int mpc5125_psc_raw_rx_rdy(struct uart_port *port)
 {
 	return !(in_be32(&FIFO_5125(port)->rxsr) & MPC512x_PSC_FIFO_EMPTY);
 }
 
-static int mpc5125_psc_raw_tx_rdy(struct uart_port *port)
+static unsigned int mpc5125_psc_raw_tx_rdy(struct uart_port *port)
 {
 	return !(in_be32(&FIFO_5125(port)->txsr) & MPC512x_PSC_FIFO_FULL);
 }
 
-static int mpc5125_psc_rx_rdy(struct uart_port *port)
+static unsigned int mpc5125_psc_rx_rdy(struct uart_port *port)
 {
 	return in_be32(&FIFO_5125(port)->rxsr) &
 	       in_be32(&FIFO_5125(port)->rximr) & MPC512x_PSC_FIFO_ALARM;
 }
 
-static int mpc5125_psc_tx_rdy(struct uart_port *port)
+static unsigned int mpc5125_psc_tx_rdy(struct uart_port *port)
 {
 	return in_be32(&FIFO_5125(port)->txsr) &
 	       in_be32(&FIFO_5125(port)->tximr) & MPC512x_PSC_FIFO_ALARM;
 }
 
-static int mpc5125_psc_tx_empty(struct uart_port *port)
+static unsigned int mpc5125_psc_tx_empty(struct uart_port *port)
 {
 	return in_be32(&FIFO_5125(port)->txsr) & MPC512x_PSC_FIFO_EMPTY;
 }