[3/5] pinctrl: add helpers reading pins, groups & functions from DT

diff --git a/drivers/pinctrl/core.c b/drivers/pinctrl/core.c
index ffe39336fcac..8f6ed8488313 100644
--- a/drivers/pinctrl/core.c
+++ b/drivers/pinctrl/core.c
@@ -515,8 +515,97 @@  void pinctrl_remove_gpio_range(struct pinctrl_dev *pctldev,
 }
 EXPORT_SYMBOL_GPL(pinctrl_remove_gpio_range);
 
+int pinctrl_generic_get_dt_pins(struct pinctrl_desc *pctldesc,
+				struct device *dev)
+{
+	struct pinctrl_pin_desc *descs;
+	struct device_node *pins;
+	struct device_node *np;
+	int err = 0;
+	int i = 0;
+
+	pins = of_get_child_by_name(dev->of_node, "pins");
+	if (!pins) {
+		dev_err(dev, "failed to find \"pins\" DT node\n");
+		err = -ENOENT;
+		goto err_out;
+	}
+
+	pctldesc->npins = of_get_available_child_count(pins);
+
+	descs = devm_kcalloc(dev, pctldesc->npins, sizeof(*descs), GFP_KERNEL);
+	if (!descs) {
+		err = -ENOMEM;
+		goto err_put_node;
+	}
+
+	for_each_available_child_of_node(pins, np) {
+		if (of_property_read_u32(np, "reg", &descs[i].number)) {
+			dev_err(dev, "missing \"reg\" property in %pOF\n", np);
+			err = -ENOENT;
+			goto err_put_node;
+		}
+
+		if (of_property_read_string(np, "label", &descs[i].name)) {
+			dev_err(dev, "missing \"label\" property in %pOF\n", np);
+			err = -ENOENT;
+			goto err_put_node;
+		}
+
+		i++;
+	}
+
+	pctldesc->pins = descs;
+
+err_put_node:
+	of_node_put(pins);
+err_out:
+	return err;
+}
+EXPORT_SYMBOL_GPL(pinctrl_generic_get_dt_pins);
+
 #ifdef CONFIG_GENERIC_PINCTRL_GROUPS
 
+int pinctrl_generic_get_dt_groups(struct pinctrl_dev *pctldev)
+{
+	struct device *dev = pctldev->dev;
+	struct device_node *groups;
+	struct device_node *np;
+	int err = 0;
+
+	groups = of_get_child_by_name(dev->of_node, "groups");
+	if (!groups) {
+		dev_err(dev, "failed to find \"groups\" DT node\n");
+		err = -ENOENT;
+		goto err_out;
+	}
+
+	for_each_available_child_of_node(groups, np) {
+		int num_pins;
+		u32 *pins;
+
+		num_pins = of_property_count_u32_elems(np, "pins");
+		pins = devm_kmalloc_array(dev, num_pins, sizeof(*pins), GFP_KERNEL);
+		if (!pins) {
+			err = -ENOMEM;
+			goto err_put_node;
+		}
+
+		if (of_property_read_u32_array(np, "pins", pins, num_pins)) {
+			err = -EIO;
+			goto err_put_node;
+		}
+
+		pinctrl_generic_add_group(pctldev, np->name, pins, num_pins, np);
+	}
+
+err_put_node:
+	of_node_put(groups);
+err_out:
+	return err;
+}
+EXPORT_SYMBOL_GPL(pinctrl_generic_get_dt_groups);
+
 /**
  * pinctrl_generic_get_group_count() - returns the number of pin groups
  * @pctldev: pin controller device
diff --git a/drivers/pinctrl/core.h b/drivers/pinctrl/core.h
index 840103c40c14..59661d4d4cc7 100644
--- a/drivers/pinctrl/core.h
+++ b/drivers/pinctrl/core.h
@@ -182,6 +182,9 @@  struct pinctrl_maps {
 	unsigned num_maps;
 };
 
+int pinctrl_generic_get_dt_pins(struct pinctrl_desc *pctldesc,
+				struct device *dev);
+
 #ifdef CONFIG_GENERIC_PINCTRL_GROUPS
 
 /**
@@ -198,6 +201,8 @@  struct group_desc {
 	void *data;
 };
 
+int pinctrl_generic_get_dt_groups(struct pinctrl_dev *pctldev);
+
 int pinctrl_generic_get_group_count(struct pinctrl_dev *pctldev);
 
 const char *pinctrl_generic_get_group_name(struct pinctrl_dev *pctldev,
diff --git a/drivers/pinctrl/pinmux.c b/drivers/pinctrl/pinmux.c
index 6cdbd9ccf2f0..5e34bd3135f5 100644
--- a/drivers/pinctrl/pinmux.c
+++ b/drivers/pinctrl/pinmux.c
@@ -24,6 +24,7 @@ 
 #include <linux/string.h>
 #include <linux/debugfs.h>
 #include <linux/seq_file.h>
+#include <linux/of.h>
 #include <linux/pinctrl/machine.h>
 #include <linux/pinctrl/pinmux.h>
 #include "core.h"
@@ -788,6 +789,48 @@  void pinmux_init_device_debugfs(struct dentry *devroot,
 
 #ifdef CONFIG_GENERIC_PINMUX_FUNCTIONS
 
+int pinmux_generic_get_dt_functions(struct pinctrl_dev *pctldev)
+{
+	struct device *dev = pctldev->dev;
+	struct device_node *functions;
+	struct device_node *np;
+	int err = 0;
+
+	functions = of_get_child_by_name(dev->of_node, "functions");
+	if (!functions) {
+		dev_err(dev, "failed to find \"functions\" DT node\n");
+		err = -ENOENT;
+		goto err_out;
+	}
+
+	for_each_available_child_of_node(functions, np) {
+		int num_groups = of_count_phandle_with_args(np, "groups", NULL);
+		struct of_phandle_iterator it;
+		const char **groups;
+		int ret;
+		int i;
+
+		groups = devm_kmalloc_array(dev, num_groups, sizeof(*groups), GFP_KERNEL);
+		if (!groups) {
+			err = -ENOMEM;
+			goto err_put_node;
+		}
+
+		i = 0;
+		of_for_each_phandle(&it, ret, np, "groups", NULL, 0) {
+			groups[i++] = it.node->name;
+		}
+
+		pinmux_generic_add_function(pctldev, np->name, groups, num_groups, np);
+	}
+
+err_put_node:
+	of_node_put(functions);
+err_out:
+	return err;
+}
+EXPORT_SYMBOL_GPL(pinmux_generic_get_dt_functions);
+
 /**
  * pinmux_generic_get_function_count() - returns number of functions
  * @pctldev: pin controller device
diff --git a/drivers/pinctrl/pinmux.h b/drivers/pinctrl/pinmux.h
index 78c3a31be882..ca69025fce46 100644
--- a/drivers/pinctrl/pinmux.h
+++ b/drivers/pinctrl/pinmux.h
@@ -134,6 +134,8 @@  struct function_desc {
 	void *data;
 };
 
+int pinmux_generic_get_dt_functions(struct pinctrl_dev *pctldev);
+
 int pinmux_generic_get_function_count(struct pinctrl_dev *pctldev);
 
 const char *