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author | 2013-10-15 20:14:20 +0100 | |
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committer | 2013-10-18 00:56:05 +0100 | |
commit | a06ccd9c3785fa5550917ae036944f4e080b5749 (patch) | |
tree | 9314ebad2316f4f1e016f53e8f10eb0fbf911190 /drivers/regulator/core.c | |
parent | regulator: core: Split devres code out into a separate file (diff) | |
download | linux-a06ccd9c3785fa5550917ae036944f4e080b5749.tar.gz linux-a06ccd9c3785fa5550917ae036944f4e080b5749.tar.bz2 linux-a06ccd9c3785fa5550917ae036944f4e080b5749.zip |
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>
Diffstat (limited to 'drivers/regulator/core.c')
-rw-r--r-- | drivers/regulator/core.c | 170 |
1 files changed, 170 insertions, 0 deletions
diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c index 906deb7354ed..16427de56ce8 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 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, ®ulator_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, ®ulator_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) |