pinctrl: do not init debugfs entries for unimplemented functionalities

Commit c420619d "pinctrl: pinconf: remove checks on ops->pin_config_get"
removed the check on (ops != NULL) when performing pinconf_pins_show() or
pinconf_groups_show(). As these entries are always enabled, even if
pinconf is not supported, reading will result in an oops due to NULL
ops.

Instead of checking for ops, remove the corresponding debugfs entries if
pinconf and/or pinmux are not implemented.

Tested on OMAP3 (pinctrl-single).

Cc: stable@vger.kernel.org
Signed-off-by: NFlorian Vaussard <florian.vaussard@epfl.ch>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

drivers/pinctrl/core.c

@@ -1644,8 +1644,10 @@ static void pinctrl_init_device_debugfs(struct pinctrl_dev *pctldev)
 			    device_root, pctldev, &pinctrl_groups_ops);
 	debugfs_create_file("gpio-ranges", S_IFREG | S_IRUGO,
 			    device_root, pctldev, &pinctrl_gpioranges_ops);
-	pinmux_init_device_debugfs(device_root, pctldev);
-	pinconf_init_device_debugfs(device_root, pctldev);
+	if (pctldev->desc->pmxops)
+		pinmux_init_device_debugfs(device_root, pctldev);
+	if (pctldev->desc->confops)
+		pinconf_init_device_debugfs(device_root, pctldev);
 }
 
 static void pinctrl_remove_device_debugfs(struct pinctrl_dev *pctldev)