3.6-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Haojian Zhuang <haojian.zhuang@gmail.com>

commit 7ae9d71e8df27a3ab60a05ae3add08728debc09c upstream.

Mutex is locked duplicatly by pinconf_groups_show() and
pin_config_group_get(). It results dead lock. So avoid to lock mutex
in pinconf_groups_show().

Signed-off-by: Haojian Zhuang <haojian.zhuang@gmail.com>
Signed-off-by: Linus Walleij <redacted>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/pinctrl/pinconf.c |    4 ----
 1 file changed, 4 deletions(-)

--- a/drivers/pinctrl/pinconf.c
+++ b/drivers/pinctrl/pinconf.c

@@ -537,8 +537,6 @@ static int pinconf_groups_show(struct se
 	seq_puts(s, "Pin config settings per pin group\n");
 	seq_puts(s, "Format: group (name): configs\n");
 
-	mutex_lock(&pinctrl_mutex);
-
 	while (selector < ngroups) {
 		const char *gname = pctlops->get_group_name(pctldev, selector);
 

@@ -549,8 +547,6 @@ static int pinconf_groups_show(struct se
 		selector++;
 	}
 
-	mutex_unlock(&pinctrl_mutex);
-
 	return 0;
 }