pinctrl: implement pinctrl_check_ops

Most code assumes that the pinctrl ops are present. Validate this when
registering a pinctrl driver. Remove the one place in the code that
was checking whether one of these non-optional ops was present.

Signed-off-by: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

diff --git a/drivers/pinctrl/core.c b/drivers/pinctrl/core.c
index ec3b8cc..df6296c 100644 (file)
--- a/drivers/pinctrl/core.c
+++ b/drivers/pinctrl/core.c
@@ -908,10 +908,6 @@ static int pinctrl_groups_show(struct seq_file *s, void *what)
        const struct pinctrl_ops *ops = pctldev->desc->pctlops;
        unsigned selector = 0;
 
-       /* No grouping */
-       if (!ops)
-               return 0;
-
        mutex_lock(&pinctrl_mutex);
 
        seq_puts(s, "registered pin groups:\n");
@@ -1225,6 +1221,19 @@ static void pinctrl_remove_device_debugfs(struct pinctrl_dev *pctldev)
 
 #endif
 
+static int pinctrl_check_ops(struct pinctrl_dev *pctldev)
+{
+       const struct pinctrl_ops *ops = pctldev->desc->pctlops;
+
+       if (!ops ||
+           !ops->list_groups ||
+           !ops->get_group_name ||
+           !ops->get_group_pins)
+               return -EINVAL;
+
+       return 0;
+}
+
 /**
  * pinctrl_register() - register a pin controller device
  * @pctldesc: descriptor for this pin controller
@@ -1256,6 +1265,14 @@ struct pinctrl_dev *pinctrl_register(struct pinctrl_desc *pctldesc,
        INIT_LIST_HEAD(&pctldev->gpio_ranges);
        pctldev->dev = dev;
 
+       /* check core ops for sanity */
+       ret = pinctrl_check_ops(pctldev);
+       if (ret) {
+               pr_err("%s pinctrl ops lacks necessary functions\n",
+                       pctldesc->name);
+               goto out_err;
+       }
+
        /* If we're implementing pinmuxing, check the ops for sanity */
        if (pctldesc->pmxops) {
                ret = pinmux_check_ops(pctldev);