[PATCH] pinctrl: aspeed: Fix potential NULL dereference in aspeed_pinmux_set_mux()

[Haowen Bai]

pdesc could be null but still dereference pdesc->name and it will lead to
a null pointer access. So we move a null check before dereference.

Signed-off-by: Haowen Bai <baihaowen at meizu.com>
---
 drivers/pinctrl/aspeed/pinctrl-aspeed.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/pinctrl/aspeed/pinctrl-aspeed.c b/drivers/pinctrl/aspeed/pinctrl-aspeed.c
index c94e24aadf92..83d47ff1cea8 100644
--- a/drivers/pinctrl/aspeed/pinctrl-aspeed.c
+++ b/drivers/pinctrl/aspeed/pinctrl-aspeed.c
@@ -236,11 +236,11 @@ int aspeed_pinmux_set_mux(struct pinctrl_dev *pctldev, unsigned int function,
 		const struct aspeed_sig_expr **funcs;
 		const struct aspeed_sig_expr ***prios;
 
-		pr_debug("Muxing pin %s for %s\n", pdesc->name, pfunc->name);
-
 		if (!pdesc)
 			return -EINVAL;
 
+		pr_debug("Muxing pin %s for %s\n", pdesc->name, pfunc->name);
+
 		prios = pdesc->prios;
 
 		if (!prios)
-- 
2.7.4