serial: of_serial: check the return value of clk_prepare_enable()

masahir0y · gregkh · commit 6f0c3091e73d · 2015-06-01T06:55:12.000+09:00
The function clk_prepare_enable() may fail, and in that case it
does not make sense to proceed.  Let's check its return code and
error out if it is a negative value.

Signed-off-by: Masahiro Yamada &lt;yamada.masahiro@socionext.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
diff --git a/drivers/tty/serial/of_serial.c b/drivers/tty/serial/of_serial.c
@@ -74,7 +74,10 @@ static int of_platform_serial_setup(struct platform_device *ofdev,
 			return PTR_ERR(info->clk);
 		}
 
-		clk_prepare_enable(info->clk);
+		ret = clk_prepare_enable(info->clk);
+		if (ret < 0)
+			return ret;
+
 		clk = clk_get_rate(info->clk);
 	}
 	/* If current-speed was set, then try not to change it. */

Original file line number	Diff line number	Diff line change
`@@ -74,7 +74,10 @@ static int of_platform_serial_setup(struct platform_device *ofdev,`
`74`	`74`	`return PTR_ERR(info->clk);`
`75`	`75`	`}`
`76`	`76`
`77`		`- clk_prepare_enable(info->clk);`
	`77`	`+ ret = clk_prepare_enable(info->clk);`
	`78`	`+ if (ret < 0)`
	`79`	`+ return ret;`
	`80`	`+`
`78`	`81`	`clk = clk_get_rate(info->clk);`
`79`	`82`	`}`
`80`	`83`	`/* If current-speed was set, then try not to change it. */`