From: Muhammad Usama Anjum <usama.anjum@collabora.com>
Date: Tue, 21 Dec 2021 18:41:51 +0000 (+0500)
Subject: serial: lantiq: store and compare return status correctly
X-Git-Tag: v5.17-rc1~110^2~26
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=cb559bb974536d75c8385b2caa57ab5a3862c29a;p=thirdparty%2Fkernel%2Flinux.git

serial: lantiq: store and compare return status correctly

platform_get_irq() returns signed status. It should be stored and
compared as signed value before storing to unsigned variable. Implicit
conversion from signed to unsigned and then comparison with less than
zero is wrong as unsigned value can never be less than zero.

Fixes: f087f01ca2c5 ("serial: lantiq: Use platform_get_irq() to get the interrupt")
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Link: https://lore.kernel.org/r/YcIf7+oSWWn34ND6@debian-BULLSEYE-live-builder-AMD64
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/tty/serial/lantiq.c b/drivers/tty/serial/lantiq.c
index bb059418cb824..3e324d3f0a6df 100644
--- a/drivers/tty/serial/lantiq.c
+++ b/drivers/tty/serial/lantiq.c
@@ -727,16 +727,20 @@ static int fetch_irq_lantiq(struct device *dev, struct ltq_uart_port *ltq_port)
 {
 	struct uart_port *port = &ltq_port->port;
 	struct platform_device *pdev = to_platform_device(dev);
-
-	ltq_port->tx_irq = platform_get_irq(pdev, 0);
-	if (ltq_port->tx_irq < 0)
-		return ltq_port->tx_irq;
-	ltq_port->rx_irq = platform_get_irq(pdev, 1);
-	if (ltq_port->rx_irq < 0)
-		return ltq_port->rx_irq;
-	ltq_port->err_irq = platform_get_irq(pdev, 2);
-	if (ltq_port->err_irq < 0)
-		return ltq_port->err_irq;
+	int irq;
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0)
+		return irq;
+	ltq_port->tx_irq = irq;
+	irq = platform_get_irq(pdev, 1);
+	if (irq < 0)
+		return irq;
+	ltq_port->rx_irq = irq;
+	irq = platform_get_irq(pdev, 2);
+	if (irq < 0)
+		return irq;
+	ltq_port->err_irq = irq;
 
 	port->irq = ltq_port->tx_irq;