diff mbox

[2/2] regulator: core: Add the device tree version to the regulator_get family

Message ID 1419614799-5770-3-git-send-email-gregory.clement@free-electrons.com
State Not Applicable
Delegated to: David Miller
Headers show

Commit Message

Gregory CLEMENT Dec. 26, 2014, 5:26 p.m. UTC 
This patch adds the device tree version (of_) for each member of the
regulator_get family: normal, exclusive, optional and all of the
manageable version.

The of_regulator_get* functions allow using a device node to get the
regulator instead using the device object. It is needed for the
regulator associated to a child node which is not a device, it is the
case of the SATA ports of an ahci controller for instance.

Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
---
 drivers/regulator/core.c           | 114 +++++++++++++++++++++++++++++++++----
 drivers/regulator/devres.c         |  70 ++++++++++++++++++++---
 include/linux/regulator/consumer.h |  20 +++++++
 3 files changed, 187 insertions(+), 17 deletions(-)

Comments

Mark Brown Dec. 29, 2014, 3:49 p.m. UTC | #1 
On Fri, Dec 26, 2014 at 06:26:39PM +0100, Gregory CLEMENT wrote:

> This patch adds the device tree version (of_) for each member of the
> regulator_get family: normal, exclusive, optional and all of the
> manageable version.

I'm really not keen on this - this sort of firmware specific interface
is just going to encourage the sort of problematic Linux MFD in DT stuff
people seem so enthusiastic about and needlessly DT specific code.

> The of_regulator_get* functions allow using a device node to get the
> regulator instead using the device object. It is needed for the
> regulator associated to a child node which is not a device, it is the
> case of the SATA ports of an ahci controller for instance.

It would be much better to provide a way of mapping the supplies to the
regulator using the normal APIs, for example by making the child nodes
devices (I'm not seeing anything that says why that's not possible and
it sounds like they're supposed to be physically separate devices which
sound like good candidates for being struct device) or by providing some
other alternative mapping mechanism which isn't DT specific.

Or take another look at what the bindings are doing to avoid the
requirement for this, I'd have expected these new bindings to be part of
the review here...
diff mbox

Patch

diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
index de29399b5430..74167b98797a 100644
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -127,26 +127,37 @@  static bool have_full_constraints(void)
 
 /**
  * of_get_regulator - get a regulator device node based on supply name
+ * and on device node if provided
+ *
  * @dev: Device pointer for the consumer (of regulator) device
+ * @np: Device tree node pointer on the node containing the regulator
  * @supply: regulator supply name
  *
  * Extract the regulator device node corresponding to the supply name.
  * returns the device node corresponding to the regulator if found, else
  * returns NULL.
  */
-static struct device_node *of_get_regulator(struct device *dev, const char *supply)
+static struct device_node *of_get_regulator_by_node(struct device *dev,
+						    const char *supply,
+						    struct device_node *np)
 {
 	struct device_node *regnode = NULL;
 	char prop_name[32]; /* 32 is max size of property name */
+	struct device_node *node;
+
+	if (np)
+		node = np;
+	else
+		node = dev->of_node;
 
 	dev_dbg(dev, "Looking up %s-supply from device tree\n", supply);
 
 	snprintf(prop_name, 32, "%s-supply", supply);
-	regnode = of_parse_phandle(dev->of_node, prop_name, 0);
+	regnode = of_parse_phandle(node, prop_name, 0);
 
 	if (!regnode) {
 		dev_dbg(dev, "Looking up %s property in node %s failed",
-				prop_name, dev->of_node->full_name);
+				prop_name, node->full_name);
 		return NULL;
 	}
 	return regnode;
@@ -1268,6 +1279,7 @@  static void regulator_supply_alias(struct device **dev, const char **supply)
 
 static struct regulator_dev *regulator_dev_lookup(struct device *dev,
 						  const char *supply,
+						  struct device_node *np,
 						  int *ret)
 {
 	struct regulator_dev *r;
@@ -1278,8 +1290,8 @@  static struct regulator_dev *regulator_dev_lookup(struct device *dev,
 	regulator_supply_alias(&dev, &supply);
 
 	/* first do a dt based lookup */
-	if (dev && dev->of_node) {
-		node = of_get_regulator(dev, supply);
+	if ((dev && dev->of_node) || np) {
+		node = of_get_regulator_by_node(dev, supply, np);
 		if (node) {
 			list_for_each_entry(r, &regulator_list, list)
 				if (r->dev.parent &&
@@ -1322,6 +1334,7 @@  static struct regulator_dev *regulator_dev_lookup(struct device *dev,
 
 /* Internal regulator request function */
 static struct regulator *_regulator_get(struct device *dev, const char *id,
+					struct device_node *node,
 					bool exclusive, bool allow_dummy)
 {
 	struct regulator_dev *rdev;
@@ -1344,7 +1357,7 @@  static struct regulator *_regulator_get(struct device *dev, const char *id,
 
 	mutex_lock(&regulator_list_mutex);
 
-	rdev = regulator_dev_lookup(dev, id, &ret);
+	rdev = regulator_dev_lookup(dev, id, node, &ret);
 	if (rdev)
 		goto found;
 
@@ -1431,7 +1444,7 @@  out:
  */
 struct regulator *regulator_get(struct device *dev, const char *id)
 {
-	return _regulator_get(dev, id, false, true);
+	return _regulator_get(dev, id, NULL, false, true);
 }
 EXPORT_SYMBOL_GPL(regulator_get);
 
@@ -1458,7 +1471,7 @@  EXPORT_SYMBOL_GPL(regulator_get);
  */
 struct regulator *regulator_get_exclusive(struct device *dev, const char *id)
 {
-	return _regulator_get(dev, id, true, false);
+	return _regulator_get(dev, id, NULL, true, false);
 }
 EXPORT_SYMBOL_GPL(regulator_get_exclusive);
 
@@ -1484,10 +1497,91 @@  EXPORT_SYMBOL_GPL(regulator_get_exclusive);
  */
 struct regulator *regulator_get_optional(struct device *dev, const char *id)
 {
-	return _regulator_get(dev, id, false, false);
+	return _regulator_get(dev, id, NULL, false, false);
 }
 EXPORT_SYMBOL_GPL(regulator_get_optional);
 
+/**
+ * of_regulator_get - lookup and obtain a reference to a regulator.
+ * @dev: device for regulator "consumer"
+ * @node: device node for which to get the regulator
+ * @id: Supply name or regulator ID.
+ *
+ * Returns a struct regulator corresponding to the regulator producer,
+ * or IS_ERR() condition containing errno.
+ *
+ * Use of supply names configured via regulator_set_device_supply() is
+ * strongly encouraged.  It is recommended that the supply name used
+ * should match the name used for the supply and/or the relevant
+ * device pins in the datasheet.
+ */
+struct regulator *of_regulator_get(struct device *dev,
+				   const char *id,
+				struct device_node *node)
+{
+	return _regulator_get(dev, id, node, false, true);
+}
+EXPORT_SYMBOL_GPL(of_regulator_get);
+
+/**
+ * of_regulator_get_exclusive - obtain exclusive access to a regulator.
+ * @dev: device for regulator "consumer"
+ * @node: device node for which to get the regulator
+ * @id: Supply name or regulator ID.
+ *
+ * Returns a struct regulator corresponding to the regulator producer,
+ * or IS_ERR() condition containing errno.  Other consumers will be
+ * unable to obtain this regulator while this reference is held and the
+ * use count for the regulator will be initialised to reflect the current
+ * state of the regulator.
+ *
+ * This is intended for use by consumers which cannot tolerate shared
+ * use of the regulator such as those which need to force the
+ * regulator off for correct operation of the hardware they are
+ * controlling.
+ *
+ * Use of supply names configured via regulator_set_device_supply() is
+ * strongly encouraged.  It is recommended that the supply name used
+ * should match the name used for the supply and/or the relevant
+ * device pins in the datasheet.
+ */
+struct regulator *of_regulator_get_exclusive(struct device *dev,
+					     const char *id,
+					     struct device_node *node)
+{
+	return _regulator_get(dev, id, node, true, false);
+}
+EXPORT_SYMBOL_GPL(of_regulator_get_exclusive);
+
+/**
+ * of_regulator_get_optional - obtain optional access to a regulator.
+ * @dev: device for regulator "consumer"
+ * @node: device node for which to get the regulator
+ * @id: Supply name or regulator ID.
+ *
+ * Returns a struct regulator corresponding to the regulator producer,
+ * or IS_ERR() condition containing errno.
+ *
+ * This is intended for use by consumers for devices which can have
+ * some supplies unconnected in normal use, such as some MMC devices.
+ * It can allow the regulator core to provide stub supplies for other
+ * supplies requested using normal regulator_get() calls without
+ * disrupting the operation of drivers that can handle absent
+ * supplies.
+ *
+ * Use of supply names configured via regulator_set_device_supply() is
+ * strongly encouraged.  It is recommended that the supply name used
+ * should match the name used for the supply and/or the relevant
+ * device pins in the datasheet.
+ */
+struct regulator *of_regulator_get_optional(struct device *dev,
+					    const char *id,
+					    struct device_node *node)
+{
+	return _regulator_get(dev, id, node, false, false);
+}
+EXPORT_SYMBOL_GPL(of_regulator_get_optional);
+
 /* Locks held by regulator_put() */
 static void _regulator_put(struct regulator *regulator)
 {
@@ -3714,7 +3808,7 @@  regulator_register(const struct regulator_desc *regulator_desc,
 	if (supply) {
 		struct regulator_dev *r;
 
-		r = regulator_dev_lookup(dev, supply, &ret);
+		r = regulator_dev_lookup(dev, supply, NULL, &ret);
 
 		if (ret == -ENODEV) {
 			/*
diff --git a/drivers/regulator/devres.c b/drivers/regulator/devres.c
index 8f785bc9e510..755fc07ebc33 100644
--- a/drivers/regulator/devres.c
+++ b/drivers/regulator/devres.c
@@ -30,7 +30,9 @@  static void devm_regulator_release(struct device *dev, void *res)
 	regulator_put(*(struct regulator **)res);
 }
 
-static struct regulator *_devm_regulator_get(struct device *dev, const char *id,
+static struct regulator *_devm_regulator_get(struct device *dev,
+					     const char *id,
+					     struct device_node *node,
 					     int get_type)
 {
 	struct regulator **ptr, *regulator;
@@ -41,13 +43,13 @@  static struct regulator *_devm_regulator_get(struct device *dev, const char *id,
 
 	switch (get_type) {
 	case NORMAL_GET:
-		regulator = regulator_get(dev, id);
+		regulator = of_regulator_get(dev, id, node);
 		break;
 	case EXCLUSIVE_GET:
-		regulator = regulator_get_exclusive(dev, id);
+		regulator = of_regulator_get_exclusive(dev, id, node);
 		break;
 	case OPTIONAL_GET:
-		regulator = regulator_get_optional(dev, id);
+		regulator = of_regulator_get_optional(dev, id, node);
 		break;
 	default:
 		regulator = ERR_PTR(-EINVAL);
@@ -74,7 +76,7 @@  static struct regulator *_devm_regulator_get(struct device *dev, const char *id,
  */
 struct regulator *devm_regulator_get(struct device *dev, const char *id)
 {
-	return _devm_regulator_get(dev, id, NORMAL_GET);
+	return _devm_regulator_get(dev, id, NULL, NORMAL_GET);
 }
 EXPORT_SYMBOL_GPL(devm_regulator_get);
 
@@ -90,7 +92,7 @@  EXPORT_SYMBOL_GPL(devm_regulator_get);
 struct regulator *devm_regulator_get_exclusive(struct device *dev,
 					       const char *id)
 {
-	return _devm_regulator_get(dev, id, EXCLUSIVE_GET);
+	return _devm_regulator_get(dev, id, NULL, EXCLUSIVE_GET);
 }
 EXPORT_SYMBOL_GPL(devm_regulator_get_exclusive);
 
@@ -106,10 +108,64 @@  EXPORT_SYMBOL_GPL(devm_regulator_get_exclusive);
 struct regulator *devm_regulator_get_optional(struct device *dev,
 					      const char *id)
 {
-	return _devm_regulator_get(dev, id, OPTIONAL_GET);
+	return _devm_regulator_get(dev, id, NULL, OPTIONAL_GET);
 }
 EXPORT_SYMBOL_GPL(devm_regulator_get_optional);
 
+/**
+ * devm_regulator_get - Resource managed regulator_get()
+ * @dev: device for regulator "consumer"
+ * @node: device node for which to get the regulator
+ * @id: Supply name or regulator ID.
+ *
+ * Managed regulator_get(). Regulators returned from this function are
+ * automatically regulator_put() on driver detach. See regulator_get()
+ * for more information.
+ */
+struct regulator *devm_of_regulator_get(struct device *dev,
+					const char *id,
+					struct device_node *node)
+{
+	return _devm_regulator_get(dev, id, node, NORMAL_GET);
+}
+EXPORT_SYMBOL_GPL(devm_of_regulator_get);
+
+/**
+ * devm_regulator_get_exclusive - Resource managed regulator_get_exclusive()
+ * @dev: device for regulator "consumer"
+ * @node: device node for which to get the regulator
+ * @id: Supply name or regulator ID.
+ *
+ * Managed regulator_get_exclusive(). Regulators returned from this
+ * function are automatically regulator_put() on driver detach. See
+ * regulator_get_exclusive() for more information.
+ */
+struct regulator *devm_of_regulator_get_exclusive(struct device *dev,
+						 const char *id,
+						 struct device_node *node)
+{
+	return _devm_regulator_get(dev, id, node, EXCLUSIVE_GET);
+}
+EXPORT_SYMBOL_GPL(devm_of_regulator_get_exclusive);
+
+/**
+ * devm_regulator_get_optional - Resource managed regulator_get_optional()
+ * @dev: device for regulator "consumer"
+ * @node: device node for which to get the regulator
+ * @id: Supply name or regulator ID.
+ *
+ * Managed regulator_get_optional(). Regulators returned from this
+ * function are automatically regulator_put() on driver detach. See
+ * regulator_get_optional() for more information.
+ */
+struct regulator *devm_of_regulator_get_optional(struct device *dev,
+						 const char *id,
+						 struct device_node *node)
+{
+	return _devm_regulator_get(dev, id, node, OPTIONAL_GET);
+}
+EXPORT_SYMBOL_GPL(devm_of_regulator_get_optional);
+
 static int devm_regulator_match(struct device *dev, void *res, void *data)
 {
 	struct regulator **r = res;
diff --git a/include/linux/regulator/consumer.h b/include/linux/regulator/consumer.h
index d17e1ff7ad01..1c88ce1aaa3f 100644
--- a/include/linux/regulator/consumer.h
+++ b/include/linux/regulator/consumer.h
@@ -40,6 +40,7 @@ 
 struct device;
 struct notifier_block;
 struct regmap;
+struct device_node;
 
 /*
  * Regulator operating modes.
@@ -162,14 +163,33 @@  struct regulator *__must_check regulator_get(struct device *dev,
 					     const char *id);
 struct regulator *__must_check devm_regulator_get(struct device *dev,
 					     const char *id);
+struct regulator *__must_check of_regulator_get(struct device *dev,
+						const char *id,
+						struct device_node *node);
+struct regulator *__must_check devm_of_regulator_get(struct device *dev,
+						const char *id,
+						struct device_node *node);
 struct regulator *__must_check regulator_get_exclusive(struct device *dev,
 						       const char *id);
 struct regulator *__must_check devm_regulator_get_exclusive(struct device *dev,
 							const char *id);
+struct regulator *__must_check of_regulator_get_exclusive(struct device *dev,
+						      const char *id,
+						      struct device_node *node);
+struct regulator *__must_check devm_of_regulator_get_exclusive(struct device *dev,
+						      const char *id,
+						      struct device_node *node);
 struct regulator *__must_check regulator_get_optional(struct device *dev,
 						      const char *id);
 struct regulator *__must_check devm_regulator_get_optional(struct device *dev,
 							   const char *id);
+struct regulator *__must_check of_regulator_get_optional(struct device *dev,
+						      const char *id,
+						      struct device_node *node);
+struct regulator *__must_check devm_of_regulator_get_optional(struct device *dev,
+						      const char *id,
+						      struct device_node *node);
+
 void regulator_put(struct regulator *regulator);
 void devm_regulator_put(struct regulator *regulator);