Refactor pinctrl_generic_pins_function_dt_subnode_to_map() by separating DT
parsing logic from map creation. Introduce a new helper
pinctrl_generic_to_map() to handle mapping to kernel data structures, while
keeping DT property parsing in the subnode function.

Improve code structure and enables easier reuse for platforms using
different DT properties (e.g. pinmux) without modifying the
dt_node_to_map-style callback API. Avoid unnecessary coupling to
pinctrl_generic_pins_function_dt_node_to_map(), which provides
functionality not needed when the phandle target is unambiguous.

Maximize code reuse and provide a cleaner extension point for future
pinctrl drivers.

Signed-off-by: Frank Li <Frank.Li@nxp.com>
---
change in v4
- new patch
---
 drivers/pinctrl/pinconf.h         | 18 ++++++++
 drivers/pinctrl/pinctrl-generic.c | 91 ++++++++++++++++++++++++---------------
 2 files changed, 74 insertions(+), 35 deletions(-)

diff --git a/drivers/pinctrl/pinconf.h b/drivers/pinctrl/pinconf.h
index 2880adef476e68950ffdd540ea42cdee6a16ec27..ffdabddb9660324ed8886a2e8dcacff7e1c6c529 100644
--- a/drivers/pinctrl/pinconf.h
+++ b/drivers/pinctrl/pinconf.h

@@ -166,6 +166,13 @@ int pinctrl_generic_pins_function_dt_node_to_map(struct pinctrl_dev *pctldev,
 						 struct device_node *np,
 						 struct pinctrl_map **maps,
 						 unsigned int *num_maps);
+
+int
+pinctrl_generic_to_map(struct pinctrl_dev *pctldev, struct device_node *parent,
+		       struct device_node *np, struct pinctrl_map **maps,
+		       unsigned int *num_maps, unsigned int *num_reserved_maps,
+		       const char **group_name, unsigned int ngroups,
+		       const char **functions, unsigned int *pins);
 #else
 static inline int
 pinctrl_generic_pins_function_dt_node_to_map(struct pinctrl_dev *pctldev,

@@ -175,4 +182,15 @@ pinctrl_generic_pins_function_dt_node_to_map(struct pinctrl_dev *pctldev,
 {
 	return -ENOTSUPP;
 }
+
+static inline int
+pinctrl_generic_to_map(struct pinctrl_dev *pctldev, struct device_node *parent,
+		       struct device_node *np, struct pinctrl_map **maps,
+		       unsigned int *num_maps, unsigned int *num_reserved_maps,
+		       const char **group_name, unsigned int ngroups,
+		       const char **functions, unsigned int *pins,
+		       void *function_data)
+{
+	return -ENOTSUPP;
+}
 #endif

diff --git a/drivers/pinctrl/pinctrl-generic.c b/drivers/pinctrl/pinctrl-generic.c
index efb39c6a670331775855efdc8566102b5c6202ef..20a216ae63e91b69985ea4cfcd0b57103c6ca950 100644
--- a/drivers/pinctrl/pinctrl-generic.c
+++ b/drivers/pinctrl/pinctrl-generic.c

@@ -17,29 +17,18 @@
 #include "pinctrl-utils.h"
 #include "pinmux.h"
 
-static int pinctrl_generic_pins_function_dt_subnode_to_map(struct pinctrl_dev *pctldev,
-							   struct device_node *parent,
-							   struct device_node *np,
-							   struct pinctrl_map **maps,
-							   unsigned int *num_maps,
-							   unsigned int *num_reserved_maps,
-							   const char **group_names,
-							   unsigned int ngroups)
+int
+pinctrl_generic_to_map(struct pinctrl_dev *pctldev, struct device_node *parent,
+		       struct device_node *np, struct pinctrl_map **maps,
+		       unsigned int *num_maps, unsigned int *num_reserved_maps,
+		       const char **group_names, unsigned int ngroups,
+		       const char **functions, unsigned int *pins)

+	unsigned int num_configs;
 	const char *group_name;
 	unsigned long *configs;
-	unsigned int num_configs, pin, *pins;
-	int npins, ret, reserve = 1;
-
-	npins = of_property_count_u32_elems(np, "pins");
-
-	if (npins < 1) {
-		dev_err(dev, "invalid pinctrl group %pOFn.%pOFn %d\n",
-			parent, np, npins);
-		return npins;
-	}
 
 	group_name = devm_kasprintf(dev, GFP_KERNEL, "%pOFn.%pOFn", parent, np);
 	if (!group_name)

@@ -51,22 +40,6 @@ static int pinctrl_generic_pins_function_dt_subnode_to_map(struct pinctrl_dev *p
 	if (!pins)
 		return -ENOMEM;
 
-	functions = devm_kcalloc(dev, npins, sizeof(*functions), GFP_KERNEL);
-	if (!functions)
-		return -ENOMEM;
-
-	for (int i = 0; i < npins; i++) {
-		ret = of_property_read_u32_index(np, "pins", i, &pin);
-		if (ret)
-			return ret;
-
-		pins[i] = pin;
-
-		ret = of_property_read_string(np, "function", &functions[i]);
-		if (ret)
-			return ret;
-	}
-
 	ret = pinctrl_utils_reserve_map(pctldev, maps, num_reserved_maps, num_maps, reserve);
 	if (ret)
 		return ret;

@@ -103,6 +76,54 @@ static int pinctrl_generic_pins_function_dt_subnode_to_map(struct pinctrl_dev *p
 	return 0;
 };
 
+static int
+pinctrl_generic_pins_function_dt_subnode_to_map(struct pinctrl_dev *pctldev,
+						struct device_node *parent,
+						struct device_node *np,
+						struct pinctrl_map **maps,
+						unsigned int *num_maps,
+						unsigned int *num_reserved_maps,
+						const char **group_names,
+						unsigned int ngroups)
+{
+	struct device *dev = pctldev->dev;
+	unsigned int pin, *pins;
+	const char **functions;
+	int npins, ret;
+
+	npins = of_property_count_u32_elems(np, "pins");