regulator: core: Add ability to create a lookup alias for supply

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>
Signed-off-by: Mark Brown <broonie@linaro.org>
This commit is contained in:
Charles Keepax 2013-10-15 20:14:20 +01:00 committed by Mark Brown
parent 0cdfcc0f93
commit a06ccd9c37
3 changed files with 412 additions and 0 deletions

View File

@ -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 bool board_wants_dummy_regulator;
@ -83,6 +84,19 @@ 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);
@ -1173,6 +1187,32 @@ 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)
@ -1182,6 +1222,8 @@ 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);
@ -1432,6 +1474,134 @@ 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)

View File

@ -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);

View File

@ -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;