pinctrl: fix pinmux_hog_maps when ctrl_dev_name is not set

The ctrl_dev_name is optional for struct pinmux_map assuming
that ctrl_dev is set. Without this patch we can get:

Unable to handle kernel NULL pointer dereference at virtual
address 00000000
...
(pinmux_hog_maps+0xa4/0x20c)
(pinctrl_register+0x2a4/0x378)
...

Fix this by adding adding a test for map->ctrl_dev.
Additionally move the test for map->ctrl_dev earlier
to optimize out the loop a bit.

Signed-off-by: Tony Lindgren <tony@atomide.com>
Acked-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

1 files changed, 6 insertions, 3 deletions

diff --git a/drivers/pinctrl/pinmux.c b/drivers/pinctrl/pinmux.c
index f4f8c7e4b1c8..3ffa9324ed82 100644
--- a/drivers/pinctrl/pinmux.c
+++ b/drivers/pinctrl/pinmux.c
@@ -978,9 +978,12 @@ int pinmux_hog_maps(struct pinctrl_dev *pctldev)
         for (i = 0; i < pinmux_maps_num; i++) {
                 struct pinmux_map const *map = &pinmux_maps[i];
 
-                if (((map->ctrl_dev == dev) ||
-                     !strcmp(map->ctrl_dev_name, devname)) &&
-                    map->hog_on_boot) {
+                if (!map->hog_on_boot)
+                        continue;
+
+                if ((map->ctrl_dev == dev) ||
+                        (map->ctrl_dev_name &&
+                                !strcmp(map->ctrl_dev_name, devname))) {
                         /* OK time to hog! */
                         ret = pinmux_hog_map(pctldev, map);
                         if (ret)