pinctrl: get_group_pins() const fixes

get_group_pins() "returns" a pointer to an array of const objects, through
a pointer parameter. Fix the prototype so what's pointed at by the returned
pointer is const, rather than the function parameter being const.

This also allows the removal of a cast in each of the two current pinmux
drivers.

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

drivers/pinctrl/core.c

@@ -329,7 +329,7 @@ static int pinctrl_groups_show(struct seq_file *s, void *what)
 
 	seq_puts(s, "registered pin groups:\n");
 	while (ops->list_groups(pctldev, selector) >= 0) {
-		unsigned *pins;
+		const unsigned *pins;
 		unsigned num_pins;
 		const char *gname = ops->get_group_name(pctldev, selector);
 		int ret;

drivers/pinctrl/pinmux-sirf.c

@@ -869,12 +869,12 @@ static const char *sirfsoc_get_group_name(struct pinctrl_dev *pctldev,
 }
 
 static int sirfsoc_get_group_pins(struct pinctrl_dev *pctldev, unsigned selector,
-			       unsigned ** const pins,
-			       unsigned * const num_pins)
+			       const unsigned **pins,
+			       const unsigned *num_pins)
 {
 	if (selector >= ARRAY_SIZE(sirfsoc_pin_groups))
 		return -EINVAL;
-	*pins = (unsigned *) sirfsoc_pin_groups[selector].pins;
+	*pins = sirfsoc_pin_groups[selector].pins;
 	*num_pins = sirfsoc_pin_groups[selector].num_pins;
 	return 0;
 }

drivers/pinctrl/pinmux-u300.c

@@ -849,12 +849,12 @@ static const char *u300_get_group_name(struct pinctrl_dev *pctldev,
 }
 
 static int u300_get_group_pins(struct pinctrl_dev *pctldev, unsigned selector,
-			       unsigned ** const pins,
-			       unsigned * const num_pins)
+			       const unsigned **pins,
+			       unsigned *num_pins)
 {
 	if (selector >= ARRAY_SIZE(u300_pin_groups))
 		return -EINVAL;
-	*pins = (unsigned *) u300_pin_groups[selector].pins;
+	*pins = u300_pin_groups[selector].pins;
 	*num_pins = u300_pin_groups[selector].num_pins;
 	return 0;
 }

drivers/pinctrl/pinmux.c

@@ -326,7 +326,7 @@ static int acquire_pins(struct pinctrl_dev *pctldev,
 	const struct pinmux_ops *pmxops = pctldev->desc->pmxops;
 	const char *func = pmxops->get_function_name(pctldev,
 						     func_selector);
-	unsigned *pins;
+	const unsigned *pins;
 	unsigned num_pins;
 	int ret;
 	int i;
@@ -367,7 +367,7 @@ static void release_pins(struct pinctrl_dev *pctldev,
 			 unsigned group_selector)
 {
 	const struct pinctrl_ops *pctlops = pctldev->desc->pctlops;
-	unsigned *pins;
+	const unsigned *pins;
 	unsigned num_pins;
 	int ret;
 	int i;

include/linux/pinctrl/pinctrl.h

@@ -75,8 +75,8 @@ struct pinctrl_ops {
 				       unsigned selector);
 	int (*get_group_pins) (struct pinctrl_dev *pctldev,
 			       unsigned selector,
-			       unsigned ** const pins,
-			       unsigned * const num_pins);
+			       const unsigned **pins,
+			       unsigned *num_pins);
 	void (*pin_dbg_show) (struct pinctrl_dev *pctldev, struct seq_file *s,
 			  unsigned offset);
 };