[PATCH 4.9 40/66] pinctrl: intel: merrifield: Add missed check in mrfld_config_set()

[Greg Kroah-Hartman]

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

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

From: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>

commit 19b26d92dfb70f56440c187a20c49102ab648b97 upstream.

Not every pin can be configured. Add missed check to prevent access
violation.

Fixes: 4e80c8f50574 ("pinctrl: intel: Add Intel Merrifield pin controller support")
Acked-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Signed-off-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/pinctrl/intel/pinctrl-merrifield.c |    3 +++
 1 file changed, 3 insertions(+)

--- a/drivers/pinctrl/intel/pinctrl-merrifield.c
+++ b/drivers/pinctrl/intel/pinctrl-merrifield.c
@@ -794,6 +794,9 @@ static int mrfld_config_set(struct pinct
 	unsigned int i;
 	int ret;
 
+	if (!mrfld_buf_available(mp, pin))
+		return -ENOTSUPP;
+
 	for (i = 0; i < nconfigs; i++) {
 		switch (pinconf_to_config_param(configs[i])) {
 		case PIN_CONFIG_BIAS_DISABLE: