[PATCH] serial: 8250-mtk: Fix reference leak in mtk8250_probe

[Zhang Qilong]

The pm_runtime_enable will increase power disable depth.
Thus a pairing decrement is needed on the error handling
path to keep it balanced according to context.

Fixes: e32a83c70cf98 ("serial: 8250-mtk: modify mtk uart power and clock management")
Signed-off-by: Zhang Qilong <zhangqilong3 at huawei.com>
---
 drivers/tty/serial/8250/8250_mtk.c | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/drivers/tty/serial/8250/8250_mtk.c b/drivers/tty/serial/8250/8250_mtk.c
index fa876e2c13e5..f7d3023f860f 100644
--- a/drivers/tty/serial/8250/8250_mtk.c
+++ b/drivers/tty/serial/8250/8250_mtk.c
@@ -572,15 +572,22 @@ static int mtk8250_probe(struct platform_device *pdev)
 	pm_runtime_enable(&pdev->dev);
 	err = mtk8250_runtime_resume(&pdev->dev);
 	if (err)
-		return err;
+		goto err_pm_disable;
 
 	data->line = serial8250_register_8250_port(&uart);
-	if (data->line < 0)
-		return data->line;
+	if (data->line < 0) {
+		err = data->line;
+		goto err_pm_disable;
+	}
 
 	data->rx_wakeup_irq = platform_get_irq_optional(pdev, 1);
 
 	return 0;
+
+err_pm_disable:
+	pm_runtime_disable(&pdev->dev);
+
+	return err;
 }
 
 static int mtk8250_remove(struct platform_device *pdev)
-- 
2.25.4