[PATCH] serial: mps2-uart: Check for error irq

[Jiasheng Jiang]

I find that platform_get_irq() will not always succeed.
It will return error irq in case there is no suitable irq.
Therefore, it might be better to check it if order to avoid the use of
error irq.

Fixes: 041f031def33 ("serial: mps2-uart: add MPS2 UART driver")
Signed-off-by: Jiasheng Jiang <jiasheng at iscas.ac.cn>
---
 drivers/tty/serial/mps2-uart.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/drivers/tty/serial/mps2-uart.c b/drivers/tty/serial/mps2-uart.c
index 587b42f754cb..117d9896051f 100644
--- a/drivers/tty/serial/mps2-uart.c
+++ b/drivers/tty/serial/mps2-uart.c
@@ -585,10 +585,20 @@ static int mps2_init_port(struct platform_device *pdev,
 
 	if (mps_port->flags & UART_PORT_COMBINED_IRQ) {
 		mps_port->port.irq = platform_get_irq(pdev, 0);
+		if (mps_port->port.irq < 0)
+			return mps_port->port.irq;
 	} else {
 		mps_port->rx_irq = platform_get_irq(pdev, 0);
+		if (mps_port->rx_irq < 0)
+			return mps_port->rx_irq;
+
 		mps_port->tx_irq = platform_get_irq(pdev, 1);
+		if (mps_port->tx_irq < 0)
+			return mps_port->tx_irq;
+
 		mps_port->port.irq = platform_get_irq(pdev, 2);
+		if (mps_port->port.irq < 0)
+			return mps_port->port.irq;
 	}
 
 	return ret;
-- 
2.25.1