[PATCH 0/3 v2] Add regulator supply alias

[PATCH 0/3 v2] Add regulator supply alias

[Charles Keepax]

This series of patchs adds feature to allow an alias to
be created for regulator supply lookup. This aliases will
perform the lookup on a different device from that requested
by the end user. We also add features into the MFD core to
easily map supplies from a child device to the main MFD
device.

The main use case for this is when an MFD device is
registered as a single node through device tree. It allows
frameworks dealing with the individual child drivers to
locate their regulators on the main MFD device, without any
prior knowledge of its existance. An implementation is given
using the arizona driver which has its supplies registered
this way through device tree.

This patch series is based on Mark's regulator for-next
branch.

One thing I would be interested on improving is
the function names they get very long. For example
devm_regulator_register_bulk_supply_alias, I would wonder
if swapping the register for an add and perhaps swapping
supply_alias for just alias would be acceptable? This would
give us devm_regulator_get_alias() which is a bit more
reasonable in terms of length although perhaps slightly less
idiomatic.

Changes from version 1:
 - Added bulk and devm versions for all the calls
 - Registration of the aliases is added to the MFD framework
   rather than done in the driver probe

Charles Keepax (3):
  regulator: core: Add ability to create a lookup alias for supply
  mfd: Allow mapping regulator supplies to MFD device from children
  mfd: arizona: Specify supply mappings for Arizona CODECs

 arch/arm/mach-s3c64xx/mach-crag6410.c |   12 ---
 drivers/mfd/arizona-core.c            |   32 ++++++-
 drivers/mfd/mfd-core.c                |   22 ++++-
 drivers/regulator/core.c              |  170 +++++++++++++++++++++++++++++++++
 drivers/regulator/devres.c            |  163 +++++++++++++++++++++++++++++++
 include/linux/mfd/core.h              |    6 +
 include/linux/regulator/consumer.h    |   79 +++++++++++++++
 7 files changed, 464 insertions(+), 20 deletions(-)

-- 
1.7.2.5

[PATCH 1/3 v2] regulator: core: Add ability to create a lookup alias for supply

[Charles Keepax]

These patches add the ability to create an alternative device on which
a lookup for a certain supply should be conducted.

A common use-case for this would be devices that are logically
represented as a collection of drivers within Linux but are are
presented as a single device from device tree. It this case it is
necessary for each sub device to locate their supply data on the main
device.

Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
---
 drivers/regulator/core.c           |  170 ++++++++++++++++++++++++++++++++++++
 drivers/regulator/devres.c         |  163 ++++++++++++++++++++++++++++++++++
 include/linux/regulator/consumer.h |   79 +++++++++++++++++
 3 files changed, 412 insertions(+), 0 deletions(-)

diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
index 13263d1..6382f0a 100644
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -53,6 +53,7 @@ static DEFINE_MUTEX(regulator_list_mutex);
 static LIST_HEAD(regulator_list);
 static LIST_HEAD(regulator_map_list);
 static LIST_HEAD(regulator_ena_gpio_list);
+static LIST_HEAD(regulator_supply_alias_list);
 static bool has_full_constraints;
 
 static struct dentry *debugfs_root;
@@ -82,6 +83,19 @@ struct regulator_enable_gpio {
 	unsigned int ena_gpio_invert:1;
 };
 
+/*
+ * struct regulator_supply_alias
+ *
+ * Used to map lookups for a supply onto an alternative device.
+ */
+struct regulator_supply_alias {
+	struct list_head list;
+	struct device *src_dev;
+	const char *src_supply;
+	struct device *alias_dev;
+	const char *alias_supply;
+};
+
 static int _regulator_is_enabled(struct regulator_dev *rdev);
 static int _regulator_disable(struct regulator_dev *rdev);
 static int _regulator_get_voltage(struct regulator_dev *rdev);
@@ -1208,6 +1222,32 @@ static int _regulator_get_enable_time(struct regulator_dev *rdev)
 	return rdev->desc->ops->enable_time(rdev);
 }
 
+static struct regulator_supply_alias *regulator_find_supply_alias(
+		struct device *dev, const char *supply)
+{
+	struct regulator_supply_alias *map;
+
+	list_for_each_entry(map, &regulator_supply_alias_list, list)
+		if (map->src_dev == dev && strcmp(map->src_supply, supply) == 0)
+			return map;
+
+	return NULL;
+}
+
+static void regulator_supply_alias(struct device **dev, const char **supply)
+{
+	struct regulator_supply_alias *map;
+
+	map = regulator_find_supply_alias(*dev, *supply);
+	if (map) {
+		dev_dbg(*dev, "Mapping supply %s to %s,%s\n",
+				*supply, map->alias_supply,
+				dev_name(map->alias_dev));
+		*dev = map->alias_dev;
+		*supply = map->alias_supply;
+	}
+}
+
 static struct regulator_dev *regulator_dev_lookup(struct device *dev,
 						  const char *supply,
 						  int *ret)
@@ -1217,6 +1257,8 @@ static struct regulator_dev *regulator_dev_lookup(struct device *dev,
 	struct regulator_map *map;
 	const char *devname = NULL;
 
+	regulator_supply_alias(&dev, &supply);
+
 	/* first do a dt based lookup */
 	if (dev && dev->of_node) {
 		node = of_get_regulator(dev, supply);
@@ -1465,6 +1507,134 @@ void regulator_put(struct regulator *regulator)
 }
 EXPORT_SYMBOL_GPL(regulator_put);
 
+/**
+ * regulator_register_supply_alias - Provide device alias for supply lookup
+ *
+ * @dev: device that will be given as the regulator "consumer"
+ * @id: Supply name or regulator ID
+ * @alias_dev: device that should be used to lookup the supply
+ * @alias_id: Supply name or regulator ID that should be used to lookup the
+ * supply
+ *
+ * All lookups for id on dev will instead be conducted for alias_id on
+ * alias_dev.
+ */
+int regulator_register_supply_alias(struct device *dev, const char *id,
+				    struct device *alias_dev,
+				    const char *alias_id)
+{
+	struct regulator_supply_alias *map;
+
+	map = regulator_find_supply_alias(dev, id);
+	if (map)
+		return -EEXIST;
+
+	map = kzalloc(sizeof(struct regulator_supply_alias), GFP_KERNEL);
+	if (!map)
+		return -ENOMEM;
+
+	map->src_dev = dev;
+	map->src_supply = id;
+	map->alias_dev = alias_dev;
+	map->alias_supply = alias_id;
+
+	list_add(&map->list, &regulator_supply_alias_list);
+
+	pr_info("Adding alias for supply %s,%s -> %s,%s\n",
+		id, dev_name(dev), alias_id, dev_name(alias_dev));
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(regulator_register_supply_alias);
+
+/**
+ * regulator_unregister_supply_alias - Remove device alias
+ *
+ * @dev: device that will be given as the regulator "consumer"
+ * @id: Supply name or regulator ID
+ *
+ * Remove a lookup alias if one exists for id on dev.
+ */
+void regulator_unregister_supply_alias(struct device *dev, const char *id)
+{
+	struct regulator_supply_alias *map;
+
+	map = regulator_find_supply_alias(dev, id);
+	if (map) {
+		list_del(&map->list);
+		kfree(map);
+	}
+}
+EXPORT_SYMBOL_GPL(regulator_unregister_supply_alias);
+
+/**
+ * regulator_bulk_register_supply_alias - register multiple aliases
+ *
+ * @dev: device that will be given as the regulator "consumer"
+ * @id: List of supply names or regulator IDs
+ * @alias_dev: device that should be used to lookup the supply
+ * @alias_id: List of supply names or regulator IDs that should be used to
+ * lookup the supply
+ * @num_id: Number of aliases to register
+ *
+ * @return 0 on success, an errno on failure.
+ *
+ * This helper function allows drivers to register several supply
+ * aliases in one operation.  If any of the aliases cannot be
+ * registered any aliases that were registered will be removed
+ * before returning to the caller.
+ */
+int regulator_bulk_register_supply_alias(struct device *dev, const char **id,
+					 struct device *alias_dev,
+					 const char **alias_id,
+					 int num_id)
+{
+	int i;
+	int ret;
+
+	for (i = 0; i < num_id; ++i) {
+		ret = regulator_register_supply_alias(dev, id[i], alias_dev,
+						      alias_id[i]);
+		if (ret < 0)
+			goto err;
+	}
+
+	return 0;
+
+err:
+	dev_err(dev,
+		"Failed to create supply alias %s,%s -> %s,%s\n",
+		id[i], dev_name(dev), alias_id[i], dev_name(alias_dev));
+
+	while (--i >= 0)
+		regulator_unregister_supply_alias(dev, id[i]);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(regulator_bulk_register_supply_alias);
+
+/**
+ * regulator_bulk_unregister_supply_alias - unregister multiple aliases
+ *
+ * @dev: device that will be given as the regulator "consumer"
+ * @id: List of supply names or regulator IDs
+ * @num_id: Number of aliases to unregister
+ *
+ * This helper function allows drivers to unregister several supply
+ * aliases in one operation.
+ */
+void regulator_bulk_unregister_supply_alias(struct device *dev,
+					    const char **id,
+					    int num_id)
+{
+	int i;
+
+	for (i = 0; i < num_id; ++i)
+		regulator_unregister_supply_alias(dev, id[i]);
+}
+EXPORT_SYMBOL_GPL(regulator_bulk_unregister_supply_alias);
+
+
 /* Manage enable GPIO list. Same GPIO pin can be shared among regulators */
 static int regulator_ena_gpio_request(struct regulator_dev *rdev,
 				const struct regulator_config *config)
diff --git a/drivers/regulator/devres.c b/drivers/regulator/devres.c
index 2672a02..fb7dd17 100644
--- a/drivers/regulator/devres.c
+++ b/drivers/regulator/devres.c
@@ -250,3 +250,166 @@ void devm_regulator_unregister(struct device *dev, struct regulator_dev *rdev)
 		WARN_ON(rc);
 }
 EXPORT_SYMBOL_GPL(devm_regulator_unregister);
+
+struct regulator_supply_alias_match {
+	struct device *dev;
+	const char *id;
+};
+
+static int devm_regulator_match_supply_alias(struct device *dev, void *res,
+					     void *data)
+{
+	struct regulator_supply_alias_match *match = res;
+	struct regulator_supply_alias_match *target = data;
+
+	return match->dev == target->dev && strcmp(match->id, target->id) == 0;
+}
+
+static void devm_regulator_destroy_supply_alias(struct device *dev, void *res)
+{
+	struct regulator_supply_alias_match *match = res;
+
+	regulator_unregister_supply_alias(match->dev, match->id);
+}
+
+/**
+ * devm_regulator_register_supply_alias - Resource managed
+ * regulator_register_supply_alias()
+ *
+ * @dev: device that will be given as the regulator "consumer"
+ * @id: Supply name or regulator ID
+ * @alias_dev: device that should be used to lookup the supply
+ * @alias_id: Supply name or regulator ID that should be used to lookup the
+ * supply
+ *
+ * The supply alias will automatically be unregistered when the source
+ * device is unbound.
+ */
+int devm_regulator_register_supply_alias(struct device *dev, const char *id,
+					 struct device *alias_dev,
+					 const char *alias_id)
+{
+	struct regulator_supply_alias_match *match;
+	int ret;
+
+	match = devres_alloc(devm_regulator_destroy_supply_alias,
+			   sizeof(struct regulator_supply_alias_match),
+			   GFP_KERNEL);
+	if (!match)
+		return -ENOMEM;
+
+	match->dev = dev;
+	match->id = id;
+
+	ret = regulator_register_supply_alias(dev, id, alias_dev, alias_id);
+	if (ret < 0) {
+		devres_free(match);
+		return ret;
+	}
+
+	devres_add(dev, match);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(devm_regulator_register_supply_alias);
+
+/**
+ * devm_regulator_unregister_supply_alias - Resource managed
+ * regulator_unregister_supply_alias()
+ *
+ * @dev: device that will be given as the regulator "consumer"
+ * @id: Supply name or regulator ID
+ *
+ * Unregister an alias registered with
+ * devm_regulator_register_supply_alias(). Normally this function
+ * will not need to be called and the resource management code
+ * will ensure that the resource is freed.
+ */
+void devm_regulator_unregister_supply_alias(struct device *dev, const char *id)
+{
+	struct regulator_supply_alias_match match;
+	int rc;
+
+	match.dev = dev;
+	match.id = id;
+
+	rc = devres_release(dev, devm_regulator_destroy_supply_alias,
+			    devm_regulator_match_supply_alias, &match);
+	if (rc != 0)
+		WARN_ON(rc);
+}
+EXPORT_SYMBOL_GPL(devm_regulator_unregister_supply_alias);
+
+/**
+ * devm_regulator_bulk_register_supply_alias - Managed register
+ * multiple aliases
+ *
+ * @dev: device that will be given as the regulator "consumer"
+ * @id: List of supply names or regulator IDs
+ * @alias_dev: device that should be used to lookup the supply
+ * @alias_id: List of supply names or regulator IDs that should be used to
+ * lookup the supply
+ * @num_id: Number of aliases to register
+ *
+ * @return 0 on success, an errno on failure.
+ *
+ * This helper function allows drivers to register several supply
+ * aliases in one operation, the aliases will be automatically
+ * unregisters when the source device is unbound.  If any of the
+ * aliases cannot be registered any aliases that were registered
+ * will be removed before returning to the caller.
+ */
+int devm_regulator_bulk_register_supply_alias(struct device *dev,
+					      const char **id,
+					      struct device *alias_dev,
+					      const char **alias_id,
+					      int num_id)
+{
+	int i;
+	int ret;
+
+	for (i = 0; i < num_id; ++i) {
+		ret = devm_regulator_register_supply_alias(dev, id[i],
+							   alias_dev,
+							   alias_id[i]);
+		if (ret < 0)
+			goto err;
+	}
+
+	return 0;
+
+err:
+	dev_err(dev,
+		"Failed to create supply alias %s,%s -> %s,%s\n",
+		id[i], dev_name(dev), alias_id[i], dev_name(alias_dev));
+
+	while (--i >= 0)
+		devm_regulator_unregister_supply_alias(dev, id[i]);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(devm_regulator_bulk_register_supply_alias);
+
+/**
+ * devm_regulator_bulk_unregister_supply_alias - Managed unregister
+ * multiple aliases
+ *
+ * @dev: device that will be given as the regulator "consumer"
+ * @id: List of supply names or regulator IDs
+ * @num_id: Number of aliases to unregister
+ *
+ * Unregister aliases registered with
+ * devm_regulator_bulk_register_supply_alias(). Normally this function
+ * will not need to be called and the resource management code
+ * will ensure that the resource is freed.
+ */
+void devm_regulator_bulk_unregister_supply_alias(struct device *dev,
+						 const char **id,
+						 int num_id)
+{
+	int i;
+
+	for (i = 0; i < num_id; ++i)
+		devm_regulator_unregister_supply_alias(dev, id[i]);
+}
+EXPORT_SYMBOL_GPL(devm_regulator_bulk_unregister_supply_alias);
diff --git a/include/linux/regulator/consumer.h b/include/linux/regulator/consumer.h
index 27be915..e530681 100644
--- a/include/linux/regulator/consumer.h
+++ b/include/linux/regulator/consumer.h
@@ -146,6 +146,32 @@ struct regulator *__must_check devm_regulator_get_optional(struct device *dev,
 void regulator_put(struct regulator *regulator);
 void devm_regulator_put(struct regulator *regulator);
 
+int regulator_register_supply_alias(struct device *dev, const char *id,
+				    struct device *alias_dev,
+				    const char *alias_id);
+void regulator_unregister_supply_alias(struct device *dev, const char *id);
+
+int regulator_bulk_register_supply_alias(struct device *dev, const char **id,
+					 struct device *alias_dev,
+					 const char **alias_id, int num_id);
+void regulator_bulk_unregister_supply_alias(struct device *dev,
+					    const char **id, int num_id);
+
+int devm_regulator_register_supply_alias(struct device *dev, const char *id,
+					 struct device *alias_dev,
+					 const char *alias_id);
+void devm_regulator_unregister_supply_alias(struct device *dev,
+					    const char *id);
+
+int devm_regulator_bulk_register_supply_alias(struct device *dev,
+					      const char **id,
+					      struct device *alias_dev,
+					      const char **alias_id,
+					      int num_id);
+void devm_regulator_bulk_unregister_supply_alias(struct device *dev,
+						 const char **id,
+						 int num_id);
+
 /* regulator output control and status */
 int __must_check regulator_enable(struct regulator *regulator);
 int regulator_disable(struct regulator *regulator);
@@ -250,6 +276,59 @@ static inline void devm_regulator_put(struct regulator *regulator)
 {
 }
 
+static inline int regulator_register_supply_alias(struct device *dev,
+						  const char *id,
+						  struct device *alias_dev,
+						  const char *alias_id)
+{
+	return 0;
+}
+
+static inline void regulator_unregister_supply_alias(struct device *dev,
+						    const char *id)
+{
+}
+
+static inline int regulator_bulk_register_supply_alias(struct device *dev,
+						       const char **id,
+						       struct device *alias_dev,
+						       const char **alias_id,
+						       int num_id)
+{
+	return 0;
+}
+
+static inline void regulator_bulk_unregister_supply_alias(struct device *dev,
+							  const char **id,
+							  int num_id)
+{
+}
+
+static inline int devm_regulator_register_supply_alias(struct device *dev,
+						       const char *id,
+						       struct device *alias_dev,
+						       const char *alias_id)
+{
+	return 0;
+}
+
+static inline void devm_regulator_unregister_supply_alias(struct device *dev,
+							  const char *id)
+{
+}
+
+static inline int devm_regulator_bulk_register_supply_alias(
+		struct device *dev, const char **id, struct device *alias_dev,
+		const char **alias_id, int num_id)
+{
+	return 0;
+}
+
+static inline void devm_regulator_bulk_unregister_supply_alias(
+		struct device *dev, const char **id, int num_id)
+{
+}
+
 static inline int regulator_enable(struct regulator *regulator)
 {
 	return 0;
-- 
1.7.2.5

[PATCH 2/3 v2] mfd: Allow mapping regulator supplies to MFD device from children

[Charles Keepax]

Occasionally, it is useful to map supplies from a child device onto the
MFD device. A typical usecase for this would be if the MFD device is
represented as a single node in device tree. All supplies will be
defined in device tree as existing on the MFD device. When a child
depends on frameworks which might have no knowledge of MFD to lookup
supplies on its behalf the supply will not be found.

This patch adds a list of supplies that should be looked up on the
parent rather than the child as part of the mfd_cell structure.

Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
---
 drivers/mfd/mfd-core.c   |   22 +++++++++++++++++-----
 include/linux/mfd/core.h |    6 ++++++
 2 files changed, 23 insertions(+), 5 deletions(-)

diff --git a/drivers/mfd/mfd-core.c b/drivers/mfd/mfd-core.c
index f421586..adc8ea3 100644
--- a/drivers/mfd/mfd-core.c
+++ b/drivers/mfd/mfd-core.c
@@ -20,6 +20,7 @@
 #include <linux/module.h>
 #include <linux/irqdomain.h>
 #include <linux/of.h>
+#include <linux/regulator/consumer.h>
 
 static struct device_type mfd_dev_type = {
 	.name	= "mfd_device",
@@ -99,6 +100,13 @@ static int mfd_add_device(struct device *parent, int id,
 	pdev->dev.dma_mask = parent->dma_mask;
 	pdev->dev.dma_parms = parent->dma_parms;
 
+	ret = devm_regulator_bulk_register_supply_alias(
+			&pdev->dev, cell->parent_supplies,
+			parent, cell->parent_supplies,
+			cell->num_parent_supplies);
+	if (ret < 0)
+		goto fail_res;
+
 	if (parent->of_node && cell->of_compatible) {
 		for_each_child_of_node(parent->of_node, np) {
 			if (of_device_is_compatible(np, cell->of_compatible)) {
@@ -112,12 +120,12 @@ static int mfd_add_device(struct device *parent, int id,
 		ret = platform_device_add_data(pdev,
 					cell->platform_data, cell->pdata_size);
 		if (ret)
-			goto fail_res;
+			goto fail_alias;
 	}
 
 	ret = mfd_platform_add_cell(pdev, cell);
 	if (ret)
-		goto fail_res;
+		goto fail_alias;
 
 	for (r = 0; r < cell->num_resources; r++) {
 		res[r].name = cell->resources[r].name;
@@ -152,17 +160,17 @@ static int mfd_add_device(struct device *parent, int id,
 		if (!cell->ignore_resource_conflicts) {
 			ret = acpi_check_resource_conflict(&res[r]);
 			if (ret)
-				goto fail_res;
+				goto fail_alias;
 		}
 	}
 
 	ret = platform_device_add_resources(pdev, res, cell->num_resources);
 	if (ret)
-		goto fail_res;
+		goto fail_alias;
 
 	ret = platform_device_add(pdev);
 	if (ret)
-		goto fail_res;
+		goto fail_alias;
 
 	if (cell->pm_runtime_no_callbacks)
 		pm_runtime_no_callbacks(&pdev->dev);
@@ -171,6 +179,10 @@ static int mfd_add_device(struct device *parent, int id,
 
 	return 0;
 
+fail_alias:
+	devm_regulator_bulk_unregister_supply_alias(&pdev->dev,
+						    cell->parent_supplies,
+						    cell->num_parent_supplies);
 fail_res:
 	kfree(res);
 fail_device:
diff --git a/include/linux/mfd/core.h b/include/linux/mfd/core.h
index cebe97e..7314fc4 100644
--- a/include/linux/mfd/core.h
+++ b/include/linux/mfd/core.h
@@ -59,6 +59,12 @@ struct mfd_cell {
 	 * pm_runtime_no_callbacks().
 	 */
 	bool			pm_runtime_no_callbacks;
+
+	/* A list of regulator supplies that should be mapped to the MFD
+	 * device rather than the child device when requested
+	 */
+	const char		**parent_supplies;
+	int			num_parent_supplies;
 };
 
 /*
-- 
1.7.2.5

[PATCH 3/3 v2] mfd: arizona: Specify supply mappings for Arizona CODECs

[Charles Keepax]

The CODEC power supplies should be looked up on the Arizona device as
they will be created here by device tree also update the only user of
non-device tree bindings.

Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
---
 arch/arm/mach-s3c64xx/mach-crag6410.c |   12 ------------
 drivers/mfd/arizona-core.c            |   32 +++++++++++++++++++++++++++++---
 2 files changed, 29 insertions(+), 15 deletions(-)

diff --git a/arch/arm/mach-s3c64xx/mach-crag6410.c b/arch/arm/mach-s3c64xx/mach-crag6410.c
index eb8e5a1..f27ca3b 100644
--- a/arch/arm/mach-s3c64xx/mach-crag6410.c
+++ b/arch/arm/mach-s3c64xx/mach-crag6410.c
@@ -310,10 +310,6 @@ static struct regulator_consumer_supply wallvdd_consumers[] = {
 
 	REGULATOR_SUPPLY("SPKVDDL", "spi0.1"),
 	REGULATOR_SUPPLY("SPKVDDR", "spi0.1"),
-	REGULATOR_SUPPLY("SPKVDDL", "wm5102-codec"),
-	REGULATOR_SUPPLY("SPKVDDR", "wm5102-codec"),
-	REGULATOR_SUPPLY("SPKVDDL", "wm5110-codec"),
-	REGULATOR_SUPPLY("SPKVDDR", "wm5110-codec"),
 
 	REGULATOR_SUPPLY("DC1VDD", "0-0034"),
 	REGULATOR_SUPPLY("DC2VDD", "0-0034"),
@@ -653,14 +649,6 @@ static struct regulator_consumer_supply pvdd_1v8_consumers[] = {
 	REGULATOR_SUPPLY("DBVDD3", "spi0.1"),
 	REGULATOR_SUPPLY("LDOVDD", "spi0.1"),
 	REGULATOR_SUPPLY("CPVDD", "spi0.1"),
-
-	REGULATOR_SUPPLY("DBVDD2", "wm5102-codec"),
-	REGULATOR_SUPPLY("DBVDD3", "wm5102-codec"),
-	REGULATOR_SUPPLY("CPVDD", "wm5102-codec"),
-
-	REGULATOR_SUPPLY("DBVDD2", "wm5110-codec"),
-	REGULATOR_SUPPLY("DBVDD3", "wm5110-codec"),
-	REGULATOR_SUPPLY("CPVDD", "wm5110-codec"),
 };
 
 static struct regulator_init_data pvdd_1v8 = {
diff --git a/drivers/mfd/arizona-core.c b/drivers/mfd/arizona-core.c
index 5ac3aa4..022b186 100644
--- a/drivers/mfd/arizona-core.c
+++ b/drivers/mfd/arizona-core.c
@@ -569,13 +569,25 @@ static struct mfd_cell early_devs[] = {
 	{ .name = "arizona-ldo1" },
 };
 
+static const char *wm5102_supplies[] = {
+	"DBVDD2",
+	"DBVDD3",
+	"CPVDD",
+	"SPKVDDL",
+	"SPKVDDR",
+};
+
 static struct mfd_cell wm5102_devs[] = {
 	{ .name = "arizona-micsupp" },
 	{ .name = "arizona-extcon" },
 	{ .name = "arizona-gpio" },
 	{ .name = "arizona-haptics" },
 	{ .name = "arizona-pwm" },
-	{ .name = "wm5102-codec" },
+	{
+		.name = "wm5102-codec",
+		.parent_supplies = wm5102_supplies,
+		.num_parent_supplies = ARRAY_SIZE(wm5102_supplies),
+	},
 };
 
 static struct mfd_cell wm5110_devs[] = {
@@ -584,7 +596,17 @@ static struct mfd_cell wm5110_devs[] = {
 	{ .name = "arizona-gpio" },
 	{ .name = "arizona-haptics" },
 	{ .name = "arizona-pwm" },
-	{ .name = "wm5110-codec" },
+	{
+		.name = "wm5110-codec",
+		.parent_supplies = wm5102_supplies,
+		.num_parent_supplies = ARRAY_SIZE(wm5102_supplies),
+	},
+};
+
+static const char *wm8997_supplies[] = {
+	"DBVDD2",
+	"CPVDD",
+	"SPKVDD",
 };
 
 static struct mfd_cell wm8997_devs[] = {
@@ -593,7 +615,11 @@ static struct mfd_cell wm8997_devs[] = {
 	{ .name = "arizona-gpio" },
 	{ .name = "arizona-haptics" },
 	{ .name = "arizona-pwm" },
-	{ .name = "wm8997-codec" },
+	{
+		.name = "wm8997-codec",
+		.parent_supplies = wm8997_supplies,
+		.num_parent_supplies = ARRAY_SIZE(wm8997_supplies),
+	},
 };
 
 int arizona_dev_init(struct arizona *arizona)
-- 
1.7.2.5

[PATCH 0/3 v2] Add regulator supply alias

[Charles Keepax]

This series of patchs adds feature to allow an alias to
be created for regulator supply lookup. This aliases will
perform the lookup on a different device from that requested
by the end user. We also add features into the MFD core to
easily map supplies from a child device to the main MFD
device.

The main use case for this is when an MFD device is
registered as a single node through device tree. It allows
frameworks dealing with the individual child drivers to
locate their regulators on the main MFD device, without any
prior knowledge of its existance. An implementation is given
using the arizona driver which has its supplies registered
this way through device tree.

This patch series is based on Mark's regulator for-next
branch.

One thing I would be interested on improving is
the function names they get very long. For example
devm_regulator_register_bulk_supply_alias, I would wonder
if swapping the register for an add and perhaps swapping
supply_alias for just alias would be acceptable? This would
give us devm_regulator_get_alias() which is a bit more
reasonable in terms of length although perhaps slightly less
idiomatic.

Changes from version 1:
 - Added bulk and devm versions for all the calls
 - Registration of the aliases is added to the MFD framework
   rather than done in the driver probe

Charles Keepax (3):
  regulator: core: Add ability to create a lookup alias for supply
  mfd: Allow mapping regulator supplies to MFD device from children
  mfd: arizona: Specify supply mappings for Arizona CODECs

 arch/arm/mach-s3c64xx/mach-crag6410.c |   12 ---
 drivers/mfd/arizona-core.c            |   32 ++++++-
 drivers/mfd/mfd-core.c                |   22 ++++-
 drivers/regulator/core.c              |  170 +++++++++++++++++++++++++++++++++
 drivers/regulator/devres.c            |  163 +++++++++++++++++++++++++++++++
 include/linux/mfd/core.h              |    6 +
 include/linux/regulator/consumer.h    |   79 +++++++++++++++
 7 files changed, 464 insertions(+), 20 deletions(-)

-- 
1.7.2.5

[PATCH 1/3 v2] regulator: core: Add ability to create a lookup alias for supply

[Charles Keepax]

These patches add the ability to create an alternative device on which
a lookup for a certain supply should be conducted.

A common use-case for this would be devices that are logically
represented as a collection of drivers within Linux but are are
presented as a single device from device tree. It this case it is
necessary for each sub device to locate their supply data on the main
device.

Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
---
 drivers/regulator/core.c           |  170 ++++++++++++++++++++++++++++++++++++
 drivers/regulator/devres.c         |  163 ++++++++++++++++++++++++++++++++++
 include/linux/regulator/consumer.h |   79 +++++++++++++++++
 3 files changed, 412 insertions(+), 0 deletions(-)

diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
index 13263d1..6382f0a 100644
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -53,6 +53,7 @@ static DEFINE_MUTEX(regulator_list_mutex);
 static LIST_HEAD(regulator_list);
 static LIST_HEAD(regulator_map_list);
 static LIST_HEAD(regulator_ena_gpio_list);
+static LIST_HEAD(regulator_supply_alias_list);
 static bool has_full_constraints;
 
 static struct dentry *debugfs_root;
@@ -82,6 +83,19 @@ struct regulator_enable_gpio {
 	unsigned int ena_gpio_invert:1;
 };
 
+/*
+ * struct regulator_supply_alias
+ *
+ * Used to map lookups for a supply onto an alternative device.
+ */
+struct regulator_supply_alias {
+	struct list_head list;
+	struct device *src_dev;
+	const char *src_supply;
+	struct device *alias_dev;
+	const char *alias_supply;
+};
+
 static int _regulator_is_enabled(struct regulator_dev *rdev);
 static int _regulator_disable(struct regulator_dev *rdev);
 static int _regulator_get_voltage(struct regulator_dev *rdev);
@@ -1208,6 +1222,32 @@ static int _regulator_get_enable_time(struct regulator_dev *rdev)
 	return rdev->desc->ops->enable_time(rdev);
 }
 
+static struct regulator_supply_alias *regulator_find_supply_alias(
+		struct device *dev, const char *supply)
+{
+	struct regulator_supply_alias *map;
+
+	list_for_each_entry(map, &regulator_supply_alias_list, list)
+		if (map->src_dev == dev && strcmp(map->src_supply, supply) == 0)
+			return map;
+
+	return NULL;
+}
+
+static void regulator_supply_alias(struct device **dev, const char **supply)
+{
+	struct regulator_supply_alias *map;
+
+	map = regulator_find_supply_alias(*dev, *supply);
+	if (map) {
+		dev_dbg(*dev, "Mapping supply %s to %s,%s\n",
+				*supply, map->alias_supply,
+				dev_name(map->alias_dev));
+		*dev = map->alias_dev;
+		*supply = map->alias_supply;
+	}
+}
+
 static struct regulator_dev *regulator_dev_lookup(struct device *dev,
 						  const char *supply,
 						  int *ret)
@@ -1217,6 +1257,8 @@ static struct regulator_dev *regulator_dev_lookup(struct device *dev,
 	struct regulator_map *map;
 	const char *devname = NULL;
 
+	regulator_supply_alias(&dev, &supply);
+
 	/* first do a dt based lookup */
 	if (dev && dev->of_node) {
 		node = of_get_regulator(dev, supply);
@@ -1465,6 +1507,134 @@ void regulator_put(struct regulator *regulator)
 }
 EXPORT_SYMBOL_GPL(regulator_put);
 
+/**
+ * regulator_register_supply_alias - Provide device alias for supply lookup
+ *
+ * @dev: device that will be given as the regulator "consumer"
+ * @id: Supply name or regulator ID
+ * @alias_dev: device that should be used to lookup the supply
+ * @alias_id: Supply name or regulator ID that should be used to lookup the
+ * supply
+ *
+ * All lookups for id on dev will instead be conducted for alias_id on
+ * alias_dev.
+ */
+int regulator_register_supply_alias(struct device *dev, const char *id,
+				    struct device *alias_dev,
+				    const char *alias_id)
+{
+	struct regulator_supply_alias *map;
+
+	map = regulator_find_supply_alias(dev, id);
+	if (map)
+		return -EEXIST;
+
+	map = kzalloc(sizeof(struct regulator_supply_alias), GFP_KERNEL);
+	if (!map)
+		return -ENOMEM;
+
+	map->src_dev = dev;
+	map->src_supply = id;
+	map->alias_dev = alias_dev;
+	map->alias_supply = alias_id;
+
+	list_add(&map->list, &regulator_supply_alias_list);
+
+	pr_info("Adding alias for supply %s,%s -> %s,%s\n",
+		id, dev_name(dev), alias_id, dev_name(alias_dev));
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(regulator_register_supply_alias);
+
+/**
+ * regulator_unregister_supply_alias - Remove device alias
+ *
+ * @dev: device that will be given as the regulator "consumer"
+ * @id: Supply name or regulator ID
+ *
+ * Remove a lookup alias if one exists for id on dev.
+ */
+void regulator_unregister_supply_alias(struct device *dev, const char *id)
+{
+	struct regulator_supply_alias *map;
+
+	map = regulator_find_supply_alias(dev, id);
+	if (map) {
+		list_del(&map->list);
+		kfree(map);
+	}
+}
+EXPORT_SYMBOL_GPL(regulator_unregister_supply_alias);
+
+/**
+ * regulator_bulk_register_supply_alias - register multiple aliases
+ *
+ * @dev: device that will be given as the regulator "consumer"
+ * @id: List of supply names or regulator IDs
+ * @alias_dev: device that should be used to lookup the supply
+ * @alias_id: List of supply names or regulator IDs that should be used to
+ * lookup the supply
+ * @num_id: Number of aliases to register
+ *
+ * @return 0 on success, an errno on failure.
+ *
+ * This helper function allows drivers to register several supply
+ * aliases in one operation.  If any of the aliases cannot be
+ * registered any aliases that were registered will be removed
+ * before returning to the caller.
+ */
+int regulator_bulk_register_supply_alias(struct device *dev, const char **id,
+					 struct device *alias_dev,
+					 const char **alias_id,
+					 int num_id)
+{
+	int i;
+	int ret;
+
+	for (i = 0; i < num_id; ++i) {
+		ret = regulator_register_supply_alias(dev, id[i], alias_dev,
+						      alias_id[i]);
+		if (ret < 0)
+			goto err;
+	}
+
+	return 0;
+
+err:
+	dev_err(dev,
+		"Failed to create supply alias %s,%s -> %s,%s\n",
+		id[i], dev_name(dev), alias_id[i], dev_name(alias_dev));
+
+	while (--i >= 0)
+		regulator_unregister_supply_alias(dev, id[i]);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(regulator_bulk_register_supply_alias);
+
+/**
+ * regulator_bulk_unregister_supply_alias - unregister multiple aliases
+ *
+ * @dev: device that will be given as the regulator "consumer"
+ * @id: List of supply names or regulator IDs
+ * @num_id: Number of aliases to unregister
+ *
+ * This helper function allows drivers to unregister several supply
+ * aliases in one operation.
+ */
+void regulator_bulk_unregister_supply_alias(struct device *dev,
+					    const char **id,
+					    int num_id)
+{
+	int i;
+
+	for (i = 0; i < num_id; ++i)
+		regulator_unregister_supply_alias(dev, id[i]);
+}
+EXPORT_SYMBOL_GPL(regulator_bulk_unregister_supply_alias);
+
+
 /* Manage enable GPIO list. Same GPIO pin can be shared among regulators */
 static int regulator_ena_gpio_request(struct regulator_dev *rdev,
 				const struct regulator_config *config)
diff --git a/drivers/regulator/devres.c b/drivers/regulator/devres.c
index 2672a02..fb7dd17 100644
--- a/drivers/regulator/devres.c
+++ b/drivers/regulator/devres.c
@@ -250,3 +250,166 @@ void devm_regulator_unregister(struct device *dev, struct regulator_dev *rdev)
 		WARN_ON(rc);
 }
 EXPORT_SYMBOL_GPL(devm_regulator_unregister);
+
+struct regulator_supply_alias_match {
+	struct device *dev;
+	const char *id;
+};
+
+static int devm_regulator_match_supply_alias(struct device *dev, void *res,
+					     void *data)
+{
+	struct regulator_supply_alias_match *match = res;
+	struct regulator_supply_alias_match *target = data;
+
+	return match->dev == target->dev && strcmp(match->id, target->id) == 0;
+}
+
+static void devm_regulator_destroy_supply_alias(struct device *dev, void *res)
+{
+	struct regulator_supply_alias_match *match = res;
+
+	regulator_unregister_supply_alias(match->dev, match->id);
+}
+
+/**
+ * devm_regulator_register_supply_alias - Resource managed
+ * regulator_register_supply_alias()
+ *
+ * @dev: device that will be given as the regulator "consumer"
+ * @id: Supply name or regulator ID
+ * @alias_dev: device that should be used to lookup the supply
+ * @alias_id: Supply name or regulator ID that should be used to lookup the
+ * supply
+ *
+ * The supply alias will automatically be unregistered when the source
+ * device is unbound.
+ */
+int devm_regulator_register_supply_alias(struct device *dev, const char *id,
+					 struct device *alias_dev,
+					 const char *alias_id)
+{
+	struct regulator_supply_alias_match *match;
+	int ret;
+
+	match = devres_alloc(devm_regulator_destroy_supply_alias,
+			   sizeof(struct regulator_supply_alias_match),
+			   GFP_KERNEL);
+	if (!match)
+		return -ENOMEM;
+
+	match->dev = dev;
+	match->id = id;
+
+	ret = regulator_register_supply_alias(dev, id, alias_dev, alias_id);
+	if (ret < 0) {
+		devres_free(match);
+		return ret;
+	}
+
+	devres_add(dev, match);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(devm_regulator_register_supply_alias);
+
+/**
+ * devm_regulator_unregister_supply_alias - Resource managed
+ * regulator_unregister_supply_alias()
+ *
+ * @dev: device that will be given as the regulator "consumer"
+ * @id: Supply name or regulator ID
+ *
+ * Unregister an alias registered with
+ * devm_regulator_register_supply_alias(). Normally this function
+ * will not need to be called and the resource management code
+ * will ensure that the resource is freed.
+ */
+void devm_regulator_unregister_supply_alias(struct device *dev, const char *id)
+{
+	struct regulator_supply_alias_match match;
+	int rc;
+
+	match.dev = dev;
+	match.id = id;
+
+	rc = devres_release(dev, devm_regulator_destroy_supply_alias,
+			    devm_regulator_match_supply_alias, &match);
+	if (rc != 0)
+		WARN_ON(rc);
+}
+EXPORT_SYMBOL_GPL(devm_regulator_unregister_supply_alias);
+
+/**
+ * devm_regulator_bulk_register_supply_alias - Managed register
+ * multiple aliases
+ *
+ * @dev: device that will be given as the regulator "consumer"
+ * @id: List of supply names or regulator IDs
+ * @alias_dev: device that should be used to lookup the supply
+ * @alias_id: List of supply names or regulator IDs that should be used to
+ * lookup the supply
+ * @num_id: Number of aliases to register
+ *
+ * @return 0 on success, an errno on failure.
+ *
+ * This helper function allows drivers to register several supply
+ * aliases in one operation, the aliases will be automatically
+ * unregisters when the source device is unbound.  If any of the
+ * aliases cannot be registered any aliases that were registered
+ * will be removed before returning to the caller.
+ */
+int devm_regulator_bulk_register_supply_alias(struct device *dev,
+					      const char **id,
+					      struct device *alias_dev,
+					      const char **alias_id,
+					      int num_id)
+{
+	int i;
+	int ret;
+
+	for (i = 0; i < num_id; ++i) {
+		ret = devm_regulator_register_supply_alias(dev, id[i],
+							   alias_dev,
+							   alias_id[i]);
+		if (ret < 0)
+			goto err;
+	}
+
+	return 0;
+
+err:
+	dev_err(dev,
+		"Failed to create supply alias %s,%s -> %s,%s\n",
+		id[i], dev_name(dev), alias_id[i], dev_name(alias_dev));
+
+	while (--i >= 0)
+		devm_regulator_unregister_supply_alias(dev, id[i]);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(devm_regulator_bulk_register_supply_alias);
+
+/**
+ * devm_regulator_bulk_unregister_supply_alias - Managed unregister
+ * multiple aliases
+ *
+ * @dev: device that will be given as the regulator "consumer"
+ * @id: List of supply names or regulator IDs
+ * @num_id: Number of aliases to unregister
+ *
+ * Unregister aliases registered with
+ * devm_regulator_bulk_register_supply_alias(). Normally this function
+ * will not need to be called and the resource management code
+ * will ensure that the resource is freed.
+ */
+void devm_regulator_bulk_unregister_supply_alias(struct device *dev,
+						 const char **id,
+						 int num_id)
+{
+	int i;
+
+	for (i = 0; i < num_id; ++i)
+		devm_regulator_unregister_supply_alias(dev, id[i]);
+}
+EXPORT_SYMBOL_GPL(devm_regulator_bulk_unregister_supply_alias);
diff --git a/include/linux/regulator/consumer.h b/include/linux/regulator/consumer.h
index 27be915..e530681 100644
--- a/include/linux/regulator/consumer.h
+++ b/include/linux/regulator/consumer.h
@@ -146,6 +146,32 @@ struct regulator *__must_check devm_regulator_get_optional(struct device *dev,
 void regulator_put(struct regulator *regulator);
 void devm_regulator_put(struct regulator *regulator);
 
+int regulator_register_supply_alias(struct device *dev, const char *id,
+				    struct device *alias_dev,
+				    const char *alias_id);
+void regulator_unregister_supply_alias(struct device *dev, const char *id);
+
+int regulator_bulk_register_supply_alias(struct device *dev, const char **id,
+					 struct device *alias_dev,
+					 const char **alias_id, int num_id);
+void regulator_bulk_unregister_supply_alias(struct device *dev,
+					    const char **id, int num_id);
+
+int devm_regulator_register_supply_alias(struct device *dev, const char *id,
+					 struct device *alias_dev,
+					 const char *alias_id);
+void devm_regulator_unregister_supply_alias(struct device *dev,
+					    const char *id);
+
+int devm_regulator_bulk_register_supply_alias(struct device *dev,
+					      const char **id,
+					      struct device *alias_dev,
+					      const char **alias_id,
+					      int num_id);
+void devm_regulator_bulk_unregister_supply_alias(struct device *dev,
+						 const char **id,
+						 int num_id);
+
 /* regulator output control and status */
 int __must_check regulator_enable(struct regulator *regulator);
 int regulator_disable(struct regulator *regulator);
@@ -250,6 +276,59 @@ static inline void devm_regulator_put(struct regulator *regulator)
 {
 }
 
+static inline int regulator_register_supply_alias(struct device *dev,
+						  const char *id,
+						  struct device *alias_dev,
+						  const char *alias_id)
+{
+	return 0;
+}
+
+static inline void regulator_unregister_supply_alias(struct device *dev,
+						    const char *id)
+{
+}
+
+static inline int regulator_bulk_register_supply_alias(struct device *dev,
+						       const char **id,
+						       struct device *alias_dev,
+						       const char **alias_id,
+						       int num_id)
+{
+	return 0;
+}
+
+static inline void regulator_bulk_unregister_supply_alias(struct device *dev,
+							  const char **id,
+							  int num_id)
+{
+}
+
+static inline int devm_regulator_register_supply_alias(struct device *dev,
+						       const char *id,
+						       struct device *alias_dev,
+						       const char *alias_id)
+{
+	return 0;
+}
+
+static inline void devm_regulator_unregister_supply_alias(struct device *dev,
+							  const char *id)
+{
+}
+
+static inline int devm_regulator_bulk_register_supply_alias(
+		struct device *dev, const char **id, struct device *alias_dev,
+		const char **alias_id, int num_id)
+{
+	return 0;
+}
+
+static inline void devm_regulator_bulk_unregister_supply_alias(
+		struct device *dev, const char **id, int num_id)
+{
+}
+
 static inline int regulator_enable(struct regulator *regulator)
 {
 	return 0;
-- 
1.7.2.5

Re: [PATCH 1/3 v2] regulator: core: Add ability to create a lookup alias for supply

[Mark Brown]

[-- Attachment #1: Type: text/plain, Size: 487 bytes --]

On Tue, Oct 15, 2013 at 08:14:20PM +0100, Charles Keepax wrote:
> These patches add the ability to create an alternative device on which
> a lookup for a certain supply should be conducted.

Applied, thanks.  This can't really be applied without pulling in large
chunks of the regulator changes due to some refactoring in the core that
it depends on, I've created a tag supply-alias but it's got a nasty diff
so it's probably best if I apply the other two patches to the regulator
tree?

[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 836 bytes --]

Re: [PATCH 1/3 v2] regulator: core: Add ability to create a lookup alias for supply

[Lee Jones]

On Fri, 18 Oct 2013, Mark Brown wrote:

> On Tue, Oct 15, 2013 at 08:14:20PM +0100, Charles Keepax wrote:
> > These patches add the ability to create an alternative device on which
> > a lookup for a certain supply should be conducted.
> 
> Applied, thanks.  This can't really be applied without pulling in large
> chunks of the regulator changes due to some refactoring in the core that
> it depends on, I've created a tag supply-alias but it's got a nasty diff
> so it's probably best if I apply the other two patches to the regulator
> tree?

If you're happy with the other two patches, I am. Would you mind
reviewing and providing your Ack? Once I have it, I'll setup a branch
you can pull from in my MFD tree.

-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog

Re: [PATCH 1/3 v2] regulator: core: Add ability to create a lookup alias for supply

[Mark Brown]

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On Fri, Oct 18, 2013 at 07:53:45AM +0100, Lee Jones wrote:

> If you're happy with the other two patches, I am. Would you mind
> reviewing and providing your Ack? Once I have it, I'll setup a branch
> you can pull from in my MFD tree.

Acked-by: Mark Brown <broonie@linaro.org>

but those patches will fail to build without the preceeding regulator
patch (which is in my tree, there's a signed commit supply-alias but it
pulls along an awfully large diffstat sadly).

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Re: [PATCH 1/3 v2] regulator: core: Add ability to create a lookup alias for supply

[Lee Jones]

On Fri, 18 Oct 2013, Mark Brown wrote:

> On Fri, Oct 18, 2013 at 07:53:45AM +0100, Lee Jones wrote:
> 
> > If you're happy with the other two patches, I am. Would you mind
> > reviewing and providing your Ack? Once I have it, I'll setup a branch
> > you can pull from in my MFD tree.
> 
> Acked-by: Mark Brown <broonie@linaro.org>
> 
> but those patches will fail to build without the preceeding regulator
> patch (which is in my tree, there's a signed commit supply-alias but it
> pulls along an awfully large diffstat sadly).

Okay, fair enough.

In which case, just take the patches and apply my Ack.

-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
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