[PATCH v2] serial: arc_uart: fix of_iomap leak in `arc_serial_probe`

[Ke Zhang]

Smatch reports:

drivers/tty/serial/arc_uart.c:631 arc_serial_probe() warn:
'port->membase' from of_iomap() not released on lines: 631.

In arc_serial_probe(), if uart_add_one_port() fails,
port->membase is not released, which would cause a resource leak.

To fix this, I replace of_iomap with devm_platform_ioremap_resource.

Fixes: 8dbe1d5e09a7 ("serial/arc: inline the probe helper")
Signed-off-by: Ke Zhang <m202171830 at hust.edu.cn>
Reviewed-by: Dongliang Mu <dzm91 at hust.edu.cn>
---
v1 -> v2: Use devm_platform_ioremap_resource() and
return that errno if an errno was returned.

This issue is found by static analysis and remains untested.
---
 drivers/tty/serial/arc_uart.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/tty/serial/arc_uart.c b/drivers/tty/serial/arc_uart.c
index 59e25f2b6632..4b2512eef577 100644
--- a/drivers/tty/serial/arc_uart.c
+++ b/drivers/tty/serial/arc_uart.c
@@ -606,10 +606,11 @@ static int arc_serial_probe(struct platform_device *pdev)
 	}
 	uart->baud = val;
 
-	port->membase = of_iomap(np, 0);
-	if (!port->membase)
+	port->membase = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(port->membase)) {
 		/* No point of dev_err since UART itself is hosed here */
-		return -ENXIO;
+		return PTR_ERR(port->membase);
+	}
 
 	port->irq = irq_of_parse_and_map(np, 0);
 
-- 
2.25.1