[PATCH v3 5/6] regulator: add support for regulator set registration

[boris.brezillon@free-electrons.com (Boris BREZILLON)]

Hello Mark,

Did you have time to take a look at this patch ?

I'd like to post a new version of this series addressing Lee's comments,
but it would be great to have your feedback on this patch before posting
a new version.

Best Regards,

Boris

On 27/05/2014 11:38, Boris BREZILLON wrote:
> PMIC devices often provide several regulators, and these regulators are
> all using the same regmap and are all attached to the same device (the
> PMIC device).
>
> Add helper functions (both simple and resource managed versions) to
> register and unregister such kind of regulator set.
>
> This implementation handles self dependency issues where one regulator
> provided the PMIC depends on another one provided by the same PMIC.
>
> Signed-off-by: Boris BREZILLON <boris.brezillon@free-electrons.com>
> ---
>  drivers/regulator/core.c         | 106 +++++++++++++++++++++++++++++++++++++++
>  drivers/regulator/devres.c       |  68 +++++++++++++++++++++++++
>  include/linux/regulator/driver.h |  51 +++++++++++++++++++
>  3 files changed, 225 insertions(+)
>
> diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
> index 9a09f3c..7703853 100644
> --- a/drivers/regulator/core.c
> +++ b/drivers/regulator/core.c
> @@ -3595,6 +3595,112 @@ void regulator_unregister(struct regulator_dev *rdev)
>  EXPORT_SYMBOL_GPL(regulator_unregister);
>  
>  /**
> + * regulator_set_register - register a set of regulators
> + * @config: runtime configuration for regulator set
> + *
> + * Called by regulator drivers to register a set of regulators.
> + * Returns a valid pointer to struct regulator_set on success
> + * or an ERR_PTR() on error.
> + */
> +struct regulator_set *
> +regulator_set_register(const struct regulator_set_config *config)
> +{
> +	struct regulator_set *rset;
> +	int prev_nregistered = -1;
> +	int nregistered = 0;
> +	int ret;
> +	int i;
> +
> +	if (!config->descs || !config->nregulators)
> +		return ERR_PTR(-EINVAL);
> +
> +	rset = kzalloc(sizeof(*rset) +
> +		       (config->nregulators * sizeof(struct regulator_dev *)),
> +		       GFP_KERNEL);
> +	if (!rset)
> +		return ERR_PTR(-ENOMEM);
> +
> +	rset->nregulators = config->nregulators;
> +
> +	while (nregistered < config->nregulators &&
> +	       prev_nregistered < nregistered) {
> +
> +		prev_nregistered = nregistered;
> +
> +		for (i = 0; i < config->nregulators; i++) {
> +			struct regulator_config conf;
> +			struct regulator_dev *regulator;
> +
> +			if (rset->regulators[i])
> +				continue;
> +
> +			memset(&conf, 0, sizeof(conf));
> +
> +			conf.dev = config->dev;
> +			conf.regmap = config->regmap;
> +			conf.driver_data = config->driver_data;
> +			if (config->matches && config->matches[i].init_data)
> +				conf.init_data = config->matches[i].init_data;
> +			else if (config->init_data)
> +				conf.init_data = config->init_data[i];
> +
> +			if (config->matches)
> +				conf.of_node = config->matches[i].of_node;
> +
> +			regulator = regulator_register(&config->descs[i],
> +						       &conf);
> +			if (IS_ERR(regulator)) {
> +				ret = PTR_ERR(regulator);
> +				if (ret == -EPROBE_DEFER)
> +					continue;
> +
> +				goto err;
> +			}
> +
> +			rset->regulators[i] = regulator;
> +			nregistered++;
> +		}
> +	}
> +
> +	if (nregistered < config->nregulators) {
> +		ret = -EPROBE_DEFER;
> +		goto err;
> +	}
> +
> +	return rset;
> +
> +err:
> +	for (i = 0; i < config->nregulators; i++) {
> +		if (rset->regulators[i])
> +			regulator_unregister(rset->regulators[i]);
> +	}
> +
> +	kfree(rset);
> +
> +	return ERR_PTR(ret);
> +}
> +EXPORT_SYMBOL_GPL(regulator_set_register);
> +
> +/**
> + * regulator_set_unregister - unregister regulator set
> + * @rset: regulator set to unregister
> + *
> + * Called by regulator drivers to unregister a regulator set.
> + */
> +void regulator_set_unregister(struct regulator_set *rset)
> +{
> +	int i;
> +
> +	for (i = 0; i < rset->nregulators; i++) {
> +		if (rset->regulators[i])
> +			regulator_unregister(rset->regulators[i]);
> +	}
> +
> +	kfree(rset);
> +}
> +EXPORT_SYMBOL_GPL(regulator_set_unregister);
> +
> +/**
>   * regulator_suspend_prepare - prepare regulators for system wide suspend
>   * @state: system suspend state
>   *
> diff --git a/drivers/regulator/devres.c b/drivers/regulator/devres.c
> index f44818b..a34f34c 100644
> --- a/drivers/regulator/devres.c
> +++ b/drivers/regulator/devres.c
> @@ -251,6 +251,74 @@ void devm_regulator_unregister(struct device *dev, struct regulator_dev *rdev)
>  }
>  EXPORT_SYMBOL_GPL(devm_regulator_unregister);
>  
> +static void devm_rset_release(struct device *dev, void *res)
> +{
> +	regulator_set_unregister(*(struct regulator_set **)res);
> +}
> +
> +/**
> + * devm_regulator_set_register - Resource managed regulator_set_register()
> + * @dev: device registering the regulator set
> + * @config: runtime configuration for regulator set
> + *
> + * Called by regulator drivers to register a set of regulators.  Returns a
> + * valid pointer to struct regulator_set on success or an ERR_PTR() on
> + * error.  The regulator will automatically be released when the device
> + * is unbound.
> + */
> +struct regulator_set *
> +devm_regulator_set_register(struct device *dev,
> +			    const struct regulator_set_config *config)
> +{
> +	struct regulator_set **ptr, *rset;
> +
> +	ptr = devres_alloc(devm_rset_release, sizeof(*ptr),
> +			   GFP_KERNEL);
> +	if (!ptr)
> +		return ERR_PTR(-ENOMEM);
> +
> +	rset = regulator_set_register(config);
> +	if (!IS_ERR(rset)) {
> +		*ptr = rset;
> +		devres_add(dev, ptr);
> +	} else {
> +		devres_free(ptr);
> +	}
> +
> +	return rset;
> +}
> +EXPORT_SYMBOL_GPL(devm_regulator_set_register);
> +
> +static int devm_rset_match(struct device *dev, void *res, void *data)
> +{
> +	struct regulator_set **r = res;
> +	if (!r || !*r) {
> +		WARN_ON(!r || !*r);
> +		return 0;
> +	}
> +	return *r == data;
> +}
> +
> +/**
> + * devm_regulator_set_unregister - Resource managed regulator_set_unregister()
> + * @dev: device unregistering the regulator set
> + * @rset: regulator set to release
> + *
> + * Unregister a regulator set registered with devm_regulator_set_register().
> + * Normally this function will not need to be called and the resource
> + * management code will ensure that the resource is freed.
> + */
> +void devm_regulator_set_unregister(struct device *dev,
> +				   struct regulator_set *rset)
> +{
> +	int rc;
> +
> +	rc = devres_release(dev, devm_rdev_release, devm_rset_match, rset);
> +	if (rc != 0)
> +		WARN_ON(rc);
> +}
> +EXPORT_SYMBOL_GPL(devm_regulator_unregister);
> +
>  struct regulator_supply_alias_match {
>  	struct device *dev;
>  	const char *id;
> diff --git a/include/linux/regulator/driver.h b/include/linux/regulator/driver.h
> index bbe03a1..b683f68 100644
> --- a/include/linux/regulator/driver.h
> +++ b/include/linux/regulator/driver.h
> @@ -350,6 +350,48 @@ struct regulator_dev {
>  	unsigned int ena_gpio_state:1;
>  };
>  
> +/**
> + * struct regulator_set_config - Dynamic regulator set descriptor
> + *
> + * This structure describe a regulator and each regulator in this set
> + * will be registered using informations passed through regulator_desc
> + * and of_regulator_match tables.
> + *
> + * @dev: struct device providing the regulator set.
> + * @driver_data: private driver data for this regulator set.
> + * @regmap: regmap to use for core regmap helpers if dev_get_regulator() is
> + *          insufficient.
> + * @descs: table of regulator descriptors.
> + * @matches: table of DT regulator descriptors. This table should have
> + *           been filled by the of_regulator_match function.
> + * @init_data: a table of init_data in case matches is NULL or the init_data
> + *             of the match entry is NULL.
> + * @nregulators: number of regulators in the regulator set.
> + */
> +struct regulator_set_config {
> +	struct device *dev;
> +	void *driver_data;
> +	struct regmap *regmap;
> +	const struct regulator_desc *descs;
> +	const struct of_regulator_match *matches;
> +	const struct regulator_init_data **init_data;
> +	int nregulators;
> +};
> +
> +/*
> + * struct regulator_set - Regulator set
> + *
> + * This structure stores a set of regulator devices provided by a single
> + * device (e.g. a PMIC device).
> + *
> + * @nregulators: number of regulators in the set
> + * @regulators: regulators table
> + */
> +struct regulator_set {
> +	int nregulators;
> +	struct regulator_dev *regulators[0];
> +};
> +
>  struct regulator_dev *
>  regulator_register(const struct regulator_desc *regulator_desc,
>  		   const struct regulator_config *config);
> @@ -360,6 +402,15 @@ devm_regulator_register(struct device *dev,
>  void regulator_unregister(struct regulator_dev *rdev);
>  void devm_regulator_unregister(struct device *dev, struct regulator_dev *rdev);
>  
> +struct regulator_set *
> +regulator_set_register(const struct regulator_set_config *config);
> +struct regulator_set *
> +devm_regulator_set_register(struct device *dev,
> +			    const struct regulator_set_config *config);
> +void regulator_set_unregister(struct regulator_set *rset);
> +void devm_regulator_set_unregister(struct device *dev,
> +				   struct regulator_set *rset);
> +
>  int regulator_notifier_call_chain(struct regulator_dev *rdev,
>  				  unsigned long event, void *data);
>  

-- 
Boris Brezillon, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com