From de1dd9fd2156874b45803299b3b27e65d5defdd9 Mon Sep 17 00:00:00 2001 From: Mark Brown Date: Mon, 29 Jul 2013 21:42:42 +0100 Subject: regulator: core: Provide hints to the core about optional supplies While the majority of supplies on devices are mandatory and can't be physically omitted for electrical reasons some devices do have optional supplies and need to know if they are missing, MMC being the most common of these. Currently the core accurately reports all errors when regulators are requested since it does not know if the supply is one that must be provided even if by a regulator software does not know about or if it is one that may genuinely be disconnected. In order to allow this behaviour to be changed and stub regulators to be provided in the former case add a new regulator request function regulator_get_optional() which provides a hint to the core that the regulator may genuinely not be connected. Currently the implementation is identical to the current behaviour, future patches will add support in the core for returning stub regulators in the case where normal regulator_get() fails and the board has requested it. Signed-off-by: Mark Brown Acked-by: Chris Ball --- drivers/regulator/core.c | 59 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 59 insertions(+) (limited to 'drivers/regulator') diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c index 288c75abc190..a27a5b6267dd 100644 --- a/drivers/regulator/core.c +++ b/drivers/regulator/core.c @@ -1409,6 +1409,65 @@ struct regulator *regulator_get_exclusive(struct device *dev, const char *id) } EXPORT_SYMBOL_GPL(regulator_get_exclusive); +/** + * regulator_get_optional - obtain optional access to a regulator. + * @dev: device for regulator "consumer" + * @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 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 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 *regulator_get_optional(struct device *dev, const char *id) +{ + return _regulator_get(dev, id, 0); +} +EXPORT_SYMBOL_GPL(regulator_get_optional); + +/** + * devm_regulator_get_optional - Resource managed regulator_get_optional() + * @dev: device for regulator "consumer" + * @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_regulator_get_optional(struct device *dev, + const char *id) +{ + struct regulator **ptr, *regulator; + + ptr = devres_alloc(devm_regulator_release, sizeof(*ptr), GFP_KERNEL); + if (!ptr) + return ERR_PTR(-ENOMEM); + + regulator = regulator_get_optional(dev, id); + if (!IS_ERR(regulator)) { + *ptr = regulator; + devres_add(dev, ptr); + } else { + devres_free(ptr); + } + + return regulator; +} +EXPORT_SYMBOL_GPL(devm_regulator_get_optional); + /* Locks held by regulator_put() */ static void _regulator_put(struct regulator *regulator) { -- cgit v1.2.3 From 9efdd27678ef5e22c27c230a08a211b702768f3a Mon Sep 17 00:00:00 2001 From: Matthias Kaehlcke Date: Sun, 25 Aug 2013 17:54:13 +0200 Subject: regulator: Add devm_regulator_get_exclusive() Add a resource managed regulator_get_exclusive() Signed-off-by: Matthias Kaehlcke Signed-off-by: Mark Brown --- drivers/regulator/core.c | 30 ++++++++++++++++++++++++++++++ include/linux/regulator/consumer.h | 2 ++ 2 files changed, 32 insertions(+) (limited to 'drivers/regulator') diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c index a27a5b6267dd..4b9039b43b6c 100644 --- a/drivers/regulator/core.c +++ b/drivers/regulator/core.c @@ -1493,6 +1493,36 @@ static void _regulator_put(struct regulator *regulator) module_put(rdev->owner); } +/** + * devm_regulator_get_exclusive - Resource managed regulator_get_exclusive() + * @dev: device for regulator "consumer" + * @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() for + * more information. + */ +struct regulator *devm_regulator_get_exclusive(struct device *dev, + const char *id) +{ + struct regulator **ptr, *regulator; + + ptr = devres_alloc(devm_regulator_release, sizeof(*ptr), GFP_KERNEL); + if (!ptr) + return ERR_PTR(-ENOMEM); + + regulator = _regulator_get(dev, id, 1); + if (!IS_ERR(regulator)) { + *ptr = regulator; + devres_add(dev, ptr); + } else { + devres_free(ptr); + } + + return regulator; +} +EXPORT_SYMBOL_GPL(devm_regulator_get_exclusive); + /** * regulator_put - "free" the regulator source * @regulator: regulator source diff --git a/include/linux/regulator/consumer.h b/include/linux/regulator/consumer.h index e2bac6db4abc..91aca11198d8 100644 --- a/include/linux/regulator/consumer.h +++ b/include/linux/regulator/consumer.h @@ -137,6 +137,8 @@ struct regulator *__must_check devm_regulator_get(struct device *dev, const char *id); 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 regulator_get_optional(struct device *dev, const char *id); struct regulator *__must_check devm_regulator_get_optional(struct device *dev, -- cgit v1.2.3