[PATCH 2/5] pinctrl: core: Add generic pinctrl functions for managing groups

[Tony Lindgren]

We can add generic helpers for pin group handling for cases where the pin
controller driver does not need to use static arrays.

Signed-off-by: Tony Lindgren <tony@xxxxxxxxxxx>
---
 drivers/pinctrl/Kconfig |   3 +
 drivers/pinctrl/core.c  | 178 ++++++++++++++++++++++++++++++++++++++++++++++++
 drivers/pinctrl/core.h  |  47 +++++++++++++
 3 files changed, 228 insertions(+)

diff --git a/drivers/pinctrl/Kconfig b/drivers/pinctrl/Kconfig
--- a/drivers/pinctrl/Kconfig
+++ b/drivers/pinctrl/Kconfig
@@ -8,6 +8,9 @@ config PINCTRL
 menu "Pin controllers"
 	depends on PINCTRL
 
+config GENERIC_PINCTRL
+	bool
+
 config PINMUX
 	bool "Support pin multiplexing controllers" if COMPILE_TEST
 
diff --git a/drivers/pinctrl/core.c b/drivers/pinctrl/core.c
--- a/drivers/pinctrl/core.c
+++ b/drivers/pinctrl/core.c
@@ -540,6 +540,182 @@ void pinctrl_remove_gpio_range(struct pinctrl_dev *pctldev,
 }
 EXPORT_SYMBOL_GPL(pinctrl_remove_gpio_range);
 
+#ifdef CONFIG_GENERIC_PINCTRL
+
+/**
+ * pinctrl_generic_get_group_count() - returns the number of pin groups
+ * @pctldev: pin controller device
+ */
+int pinctrl_generic_get_group_count(struct pinctrl_dev *pctldev)
+{
+	return pctldev->num_groups;
+}
+EXPORT_SYMBOL_GPL(pinctrl_generic_get_group_count);
+
+/**
+ * pinctrl_generic_get_group_name() - returns the name of a pin group
+ * @pctldev: pin controller device
+ * @selector: group number
+ */
+const char *pinctrl_generic_get_group_name(struct pinctrl_dev *pctldev,
+					   unsigned int selector)
+{
+	struct group_desc *group;
+
+	group = radix_tree_lookup(&pctldev->pin_group_tree,
+				  selector);
+	if (!group)
+		return NULL;
+
+	return group->name;
+}
+EXPORT_SYMBOL_GPL(pinctrl_generic_get_group_name);
+
+/**
+ * pinctrl_generic_get_group_pins() - gets the pin group pins
+ * @pctldev: pin controller device
+ * @selector: group number
+ * @pins: pins in the group
+ * @num_pins: number of pins in the group
+ */
+int pinctrl_generic_get_group_pins(struct pinctrl_dev *pctldev,
+				   unsigned int selector,
+				   const unsigned int **pins,
+				   unsigned int *num_pins)
+{
+	struct group_desc *group;
+
+	group = radix_tree_lookup(&pctldev->pin_group_tree,
+				  selector);
+	if (!group) {
+		dev_err(pctldev->dev, "%s could not find pingroup%i\n",
+			__func__, selector);
+		return -EINVAL;
+	}
+
+	*pins = group->pins;
+	*num_pins = group->num_pins;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(pinctrl_generic_get_group_pins);
+
+/**
+ * pinctrl_generic_get_group() - returns a pin group based on the number
+ * @pctldev: pin controller device
+ * @gselector: group number
+ */
+struct group_desc *pinctrl_generic_get_group(struct pinctrl_dev *pctldev,
+					     unsigned int selector)
+{
+	struct group_desc *group;
+
+	group = radix_tree_lookup(&pctldev->pin_group_tree,
+				  selector);
+	if (!group)
+		return NULL;
+
+	return group;
+}
+EXPORT_SYMBOL_GPL(pinctrl_generic_get_group);
+
+/**
+ * pinctrl_generic_add_group() - adds a new pin group
+ * @pctldev: pin controller device
+ * @name: name of the pin group
+ * @pins: pins in the pin group
+ * @num_pins: number of pins in the pin group
+ * @data: pin controller driver specific data
+ *
+ * Note that the caller must take care of locking.
+ */
+int pinctrl_generic_add_group(struct pinctrl_dev *pctldev, const char *name,
+			      int *pins, int num_pins, void *data)
+{
+	struct group_desc *group;
+
+	group = devm_kzalloc(pctldev->dev, sizeof(*group), GFP_KERNEL);
+	if (!group)
+		return -ENOMEM;
+
+	group->name = name;
+	group->pins = pins;
+	group->num_pins = num_pins;
+	group->data = data;
+
+	radix_tree_insert(&pctldev->pin_group_tree, pctldev->num_groups,
+			  group);
+
+	pctldev->num_groups++;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(pinctrl_generic_add_group);
+
+/**
+ * pinctrl_generic_remove_group() - removes a numbered pin group
+ * @pctldev: pin controller device
+ * @selector: group number
+ *
+ * Note that the caller must take care of locking.
+ */
+int pinctrl_generic_remove_group(struct pinctrl_dev *pctldev,
+				 unsigned int selector)
+{
+	struct group_desc *group;
+
+	group = radix_tree_lookup(&pctldev->pin_group_tree,
+				  selector);
+	if (!group)
+		return -ENOENT;
+
+	radix_tree_delete(&pctldev->pin_group_tree, selector);
+	devm_kfree(pctldev->dev, group);
+
+	pctldev->num_groups--;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(pinctrl_generic_remove_group);
+
+/**
+ * pinctrl_generic_free_groups() - removes all pin groups
+ * @pctldev: pin controller device
+ *
+ * Note that the caller must take care of locking.
+ */
+static void pinctrl_generic_free_groups(struct pinctrl_dev *pctldev)
+{
+	struct radix_tree_iter iter;
+	struct group_desc *group;
+	unsigned long *indices;
+	void **slot;
+	int i = 0;
+
+	indices = devm_kzalloc(pctldev->dev, sizeof(*indices) *
+			       pctldev->num_groups, GFP_KERNEL);
+	if (!indices)
+		return;
+
+	radix_tree_for_each_slot(slot, &pctldev->pin_group_tree, &iter, 0)
+		indices[i++] = iter.index;
+
+	for (i = 0; i < pctldev->num_groups; i++) {
+		group = radix_tree_lookup(&pctldev->pin_group_tree,
+					  indices[i]);
+		radix_tree_delete(&pctldev->pin_group_tree, indices[i]);
+		devm_kfree(pctldev->dev, group);
+	}
+
+	pctldev->num_groups = 0;
+}
+
+#else
+static inline void pinctrl_generic_free_groups(struct pinctrl_dev *pctldev)
+{
+}
+#endif /* CONFIG_GENERIC_PINCTRL */
+
 /**
  * pinctrl_get_group_selector() - returns the group selector for a group
  * @pctldev: the pin controller handling the group
@@ -1794,6 +1970,7 @@ struct pinctrl_dev *pinctrl_register(struct pinctrl_desc *pctldesc,
 	pctldev->desc = pctldesc;
 	pctldev->driver_data = driver_data;
 	INIT_RADIX_TREE(&pctldev->pin_desc_tree, GFP_KERNEL);
+	INIT_RADIX_TREE(&pctldev->pin_group_tree, GFP_KERNEL);
 	INIT_LIST_HEAD(&pctldev->gpio_ranges);
 	INIT_DELAYED_WORK(&pctldev->hog_work, pinctrl_hog_work);
 	pctldev->dev = dev;
@@ -1872,6 +2049,7 @@ void pinctrl_unregister(struct pinctrl_dev *pctldev)
 	mutex_lock(&pctldev->mutex);
 	/* TODO: check that no pinmuxes are still active? */
 	list_del(&pctldev->node);
+	pinctrl_generic_free_groups(pctldev);
 	/* Destroy descriptor tree */
 	pinctrl_free_pindescs(pctldev, pctldev->desc->pins,
 			      pctldev->desc->npins);
diff --git a/drivers/pinctrl/core.h b/drivers/pinctrl/core.h
--- a/drivers/pinctrl/core.h
+++ b/drivers/pinctrl/core.h
@@ -24,6 +24,8 @@ struct pinctrl_gpio_range;
  *	controller
  * @pin_desc_tree: each pin descriptor for this pin controller is stored in
  *	this radix tree
+ * @pin_group_tree: optionally each pin group can be stored in this radix tree
+ * @num_groups: optionally number of groups can be kept here
  * @gpio_ranges: a list of GPIO ranges that is handled by this pin controller,
  *	ranges are added to this list at runtime
  * @dev: the device entry for this pin controller
@@ -41,6 +43,8 @@ struct pinctrl_dev {
 	struct list_head node;
 	struct pinctrl_desc *desc;
 	struct radix_tree_root pin_desc_tree;
+	struct radix_tree_root pin_group_tree;
+	unsigned int num_groups;
 	struct list_head gpio_ranges;
 	struct device *dev;
 	struct module *owner;
@@ -162,6 +166,20 @@ struct pin_desc {
 };
 
 /**
+ * struct group_desc - generic pin group descriptor
+ * @name: name of the pin group
+ * @pins: array of pins that belong to the group
+ * @num_pins: number of pins in the group
+ * @data: pin controller driver specific data
+ */
+struct group_desc {
+	const char *name;
+	int *pins;
+	int num_pins;
+	void *data;
+};
+
+/**
  * struct pinctrl_maps - a list item containing part of the mapping table
  * @node: mapping table list node
  * @maps: array of mapping table entries
@@ -173,6 +191,35 @@ struct pinctrl_maps {
 	unsigned num_maps;
 };
 
+#ifdef CONFIG_GENERIC_PINCTRL
+
+int pinctrl_generic_get_group_count(struct pinctrl_dev *pctldev);
+
+const char *pinctrl_generic_get_group_name(struct pinctrl_dev *pctldev,
+					   unsigned int group_selector);
+
+int pinctrl_generic_get_group_pins(struct pinctrl_dev *pctldev,
+				   unsigned int group_selector,
+				   const unsigned int **pins,
+				   unsigned int *npins);
+
+struct group_desc *pinctrl_generic_get_group(struct pinctrl_dev *pctldev,
+					     unsigned int group_selector);
+
+int pinctrl_generic_add_group(struct pinctrl_dev *pctldev, const char *name,
+			      int *gpins, int ngpins, void *data);
+
+int pinctrl_generic_remove_group(struct pinctrl_dev *pctldev,
+				 unsigned int group_selector);
+
+static inline int
+pinctrl_generic_remove_last_group(struct pinctrl_dev *pctldev)
+{
+	return pinctrl_generic_remove_group(pctldev, pctldev->num_groups - 1);
+}
+
+#endif	/* CONFIG_GENERIC_PINCTRL */
+
 struct pinctrl_dev *get_pinctrl_dev_from_devname(const char *dev_name);
 struct pinctrl_dev *get_pinctrl_dev_from_of_node(struct device_node *np);
 int pin_get_from_name(struct pinctrl_dev *pctldev, const char *name);
-- 
2.9.3