pinctrl: constify pinmux_generic_get_function()

With all users of struct function_desc limited to only accessing it using
the dedicated function and never modifying it, we can now constify the
return value of pinmux_generic_get_function() treewide.

Reviewed-by: Andy Shevchenko <andy@kernel.org>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> # renesas
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be> # renesas
Tested-by: Neil Armstrong <neil.armstrong@linaro.org>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/pinctrl/freescale/pinctrl-imx.c

@@ -245,7 +245,7 @@ static int imx_pmx_set(struct pinctrl_dev *pctldev, unsigned selector,
 {
 	struct imx_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);
 	const struct imx_pinctrl_soc_info *info = ipctl->info;
-	struct function_desc *func;
+	const struct function_desc *func;
 	struct group_desc *grp;
 	struct imx_pin *pin;
 	unsigned int npins;

drivers/pinctrl/mediatek/pinctrl-airoha.c

@@ -2443,7 +2443,7 @@ static int airoha_pinmux_set_mux(struct pinctrl_dev *pctrl_dev,
 {
 	struct airoha_pinctrl *pinctrl = pinctrl_dev_get_drvdata(pctrl_dev);
 	const struct airoha_pinctrl_func *func;
-	struct function_desc *desc;
+	const struct function_desc *desc;
 	struct group_desc *grp;
 	int i;
 

drivers/pinctrl/mediatek/pinctrl-moore.c

@@ -43,7 +43,7 @@ static int mtk_pinmux_set_mux(struct pinctrl_dev *pctldev,
 			      unsigned int selector, unsigned int group)
 {
 	struct mtk_pinctrl *hw = pinctrl_dev_get_drvdata(pctldev);
-	struct function_desc *func;
+	const struct function_desc *func;
 	struct group_desc *grp;
 	int i, err;
 

drivers/pinctrl/pinctrl-equilibrium.c

@@ -325,7 +325,7 @@ static int eqbr_pinmux_set_mux(struct pinctrl_dev *pctldev,
 			       unsigned int selector, unsigned int group)
 {
 	struct eqbr_pinctrl_drv_data *pctl = pinctrl_dev_get_drvdata(pctldev);
-	struct function_desc *func;
+	const struct function_desc *func;
 	struct group_desc *grp;
 	unsigned int *pinmux;
 	int i;

drivers/pinctrl/pinctrl-ingenic.c

@@ -4000,7 +4000,7 @@ static int ingenic_pinmux_set_mux(struct pinctrl_dev *pctldev,
 		unsigned int selector, unsigned int group)
 {
 	struct ingenic_pinctrl *jzpc = pinctrl_dev_get_drvdata(pctldev);
-	struct function_desc *func;
+	const struct function_desc *func;
 	struct group_desc *grp;
 	unsigned int i;
 	uintptr_t mode;

drivers/pinctrl/pinctrl-keembay.c

@@ -935,7 +935,7 @@ static int keembay_set_mux(struct pinctrl_dev *pctldev, unsigned int fun_sel,
 			   unsigned int grp_sel)
 {
 	struct keembay_pinctrl *kpc = pinctrl_dev_get_drvdata(pctldev);
-	struct function_desc *func;
+	const struct function_desc *func;
 	struct group_desc *grp;
 	unsigned int val;
 	u8 pin_mode;

drivers/pinctrl/pinctrl-single.c

@@ -336,7 +336,7 @@ static int pcs_get_function(struct pinctrl_dev *pctldev, unsigned pin,
 	struct pcs_device *pcs = pinctrl_dev_get_drvdata(pctldev);
 	struct pin_desc *pdesc = pin_desc_get(pctldev, pin);
 	const struct pinctrl_setting_mux *setting;
-	struct function_desc *function;
+	const struct function_desc *function;
 	unsigned fselector;
 
 	/* If pin is not described in DTS & enabled, mux_setting is NULL. */
@@ -360,7 +360,7 @@ static int pcs_set_mux(struct pinctrl_dev *pctldev, unsigned fselector,
 	unsigned group)
 {
 	struct pcs_device *pcs;
-	struct function_desc *function;
+	const struct function_desc *function;
 	struct pcs_function *func;
 	int i;
 

drivers/pinctrl/pinmux.c

@@ -847,8 +847,8 @@ EXPORT_SYMBOL_GPL(pinmux_generic_get_function_groups);
  * @pctldev: pin controller device
  * @selector: function number
  */
-struct function_desc *pinmux_generic_get_function(struct pinctrl_dev *pctldev,
-						  unsigned int selector)
+const struct function_desc *
+pinmux_generic_get_function(struct pinctrl_dev *pctldev, unsigned int selector)
 {
 	struct function_desc *function;
 

drivers/pinctrl/pinmux.h

@@ -152,8 +152,8 @@ int pinmux_generic_get_function_groups(struct pinctrl_dev *pctldev,
 				       const char * const **groups,
 				       unsigned int * const ngroups);
 
-struct function_desc *pinmux_generic_get_function(struct pinctrl_dev *pctldev,
-						  unsigned int selector);
+const struct function_desc *
+pinmux_generic_get_function(struct pinctrl_dev *pctldev, unsigned int selector);
 
 int pinmux_generic_add_function(struct pinctrl_dev *pctldev,
 				const char *name,

drivers/pinctrl/renesas/pinctrl-rza1.c

@@ -1120,7 +1120,7 @@ static int rza1_set_mux(struct pinctrl_dev *pctldev, unsigned int selector,
 {
 	struct rza1_pinctrl *rza1_pctl = pinctrl_dev_get_drvdata(pctldev);
 	struct rza1_mux_conf *mux_confs;
-	struct function_desc *func;
+	const struct function_desc *func;
 	struct group_desc *grp;
 	int i;
 

drivers/pinctrl/renesas/pinctrl-rza2.c

@@ -442,7 +442,7 @@ static int rza2_set_mux(struct pinctrl_dev *pctldev, unsigned int selector,
 			unsigned int group)
 {
 	struct rza2_pinctrl_priv *priv = pinctrl_dev_get_drvdata(pctldev);
-	struct function_desc *func;
+	const struct function_desc *func;
 	unsigned int i, *psel_val;
 	struct group_desc *grp;
 

drivers/pinctrl/renesas/pinctrl-rzg2l.c

@@ -574,7 +574,7 @@ static int rzg2l_pinctrl_set_mux(struct pinctrl_dev *pctldev,
 {
 	struct rzg2l_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctldev);
 	const struct rzg2l_hwcfg *hwcfg = pctrl->data->hwcfg;
-	struct function_desc *func;
+	const struct function_desc *func;
 	unsigned int i, *psel_val;
 	struct group_desc *group;
 	const unsigned int *pins;

drivers/pinctrl/renesas/pinctrl-rzv2m.c

@@ -162,7 +162,7 @@ static int rzv2m_pinctrl_set_mux(struct pinctrl_dev *pctldev,
 				 unsigned int group_selector)
 {
 	struct rzv2m_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctldev);
-	struct function_desc *func;
+	const struct function_desc *func;
 	unsigned int i, *psel_val;
 	struct group_desc *group;
 	const unsigned int *pins;