diff options
Diffstat (limited to 'drivers/regulator/of_regulator.c')
| -rw-r--r-- | drivers/regulator/of_regulator.c | 150 |
1 files changed, 130 insertions, 20 deletions
diff --git a/drivers/regulator/of_regulator.c b/drivers/regulator/of_regulator.c index 03afc160fc72..3f490d81abc2 100644 --- a/drivers/regulator/of_regulator.c +++ b/drivers/regulator/of_regulator.c @@ -338,8 +338,10 @@ static int of_get_regulation_constraints(struct device *dev, * @desc: regulator description * * Populates regulator_init_data structure by extracting data from device - * tree node, returns a pointer to the populated structure or NULL if memory - * alloc fails. + * tree node. + * + * Return: Pointer to a populated &struct regulator_init_data or NULL if + * memory allocation fails. */ struct regulator_init_data *of_get_regulator_init_data(struct device *dev, struct device_node *node, @@ -391,7 +393,7 @@ static void devm_of_regulator_put_matches(struct device *dev, void *res) * in place and an additional of_node reference is taken for each matched * regulator. * - * Returns the number of matches found or a negative error code on failure. + * Return: The number of matches found or a negative error number on failure. */ int of_regulator_match(struct device *dev, struct device_node *node, struct of_regulator_match *matches, @@ -550,7 +552,71 @@ error: return NULL; } -struct regulator_dev *of_find_regulator_by_node(struct device_node *np) +/** + * of_get_child_regulator - get a child regulator device node + * based on supply name + * @parent: Parent device node + * @prop_name: Combination regulator supply name and "-supply" + * + * Traverse all child nodes. + * Extract the child regulator device node corresponding to the supply name. + * + * Return: Pointer to the &struct device_node corresponding to the regulator + * if found, or %NULL if not found. + */ +static struct device_node *of_get_child_regulator(struct device_node *parent, + const char *prop_name) +{ + struct device_node *regnode = NULL; + struct device_node *child = NULL; + + for_each_child_of_node(parent, child) { + regnode = of_parse_phandle(child, prop_name, 0); + if (regnode) + goto err_node_put; + + regnode = of_get_child_regulator(child, prop_name); + if (regnode) + goto err_node_put; + } + return NULL; + +err_node_put: + of_node_put(child); + return regnode; +} + +/** + * of_get_regulator - get a regulator device node based on supply name + * @dev: Device pointer for the consumer (of regulator) device + * @supply: regulator supply name + * + * Extract the regulator device node corresponding to the supply name. + * + * Return: Pointer to the &struct device_node corresponding to the regulator + * if found, or %NULL if not found. + */ +static struct device_node *of_get_regulator(struct device *dev, const char *supply) +{ + struct device_node *regnode = NULL; + char prop_name[64]; /* 64 is max size of property name */ + + dev_dbg(dev, "Looking up %s-supply from device tree\n", supply); + + snprintf(prop_name, 64, "%s-supply", supply); + regnode = of_parse_phandle(dev->of_node, prop_name, 0); + if (regnode) + return regnode; + + regnode = of_get_child_regulator(dev->of_node, prop_name); + if (regnode) + return regnode; + + dev_dbg(dev, "Looking up %s property in node %pOF failed\n", prop_name, dev->of_node); + return NULL; +} + +static struct regulator_dev *of_find_regulator_by_node(struct device_node *np) { struct device *dev; @@ -559,6 +625,46 @@ struct regulator_dev *of_find_regulator_by_node(struct device_node *np) return dev ? dev_to_rdev(dev) : NULL; } +/** + * of_regulator_dev_lookup - lookup a regulator device with device tree only + * @dev: Device pointer for regulator supply lookup. + * @supply: Supply name or regulator ID. + * + * Return: Pointer to the &struct regulator_dev on success, or ERR_PTR() + * encoded value on error. + * + * If successful, returns a pointer to the &struct regulator_dev that + * corresponds to the name @supply and with the embedded &struct device + * refcount incremented by one. The refcount must be dropped by calling + * put_device(). + * + * On failure one of the following ERR_PTR() encoded values is returned: + * * -%ENODEV if lookup fails permanently. + * * -%EPROBE_DEFER if lookup could succeed in the future. + */ +struct regulator_dev *of_regulator_dev_lookup(struct device *dev, + const char *supply) +{ + struct regulator_dev *r; + struct device_node *node; + + node = of_get_regulator(dev, supply); + if (node) { + r = of_find_regulator_by_node(node); + of_node_put(node); + if (r) + return r; + + /* + * We have a node, but there is no device. + * assume it has not registered yet. + */ + return ERR_PTR(-EPROBE_DEFER); + } + + return ERR_PTR(-ENODEV); +} + /* * Returns number of regulators coupled with rdev. */ @@ -619,7 +725,7 @@ static bool of_coupling_find_node(struct device_node *src, * - all coupled regulators have the same number of regulator_dev phandles * - all regulators are linked to each other * - * Returns true if all conditions are met. + * Return: True if all conditions are met; false otherwise. */ bool of_check_coupling_data(struct regulator_dev *rdev) { @@ -690,8 +796,8 @@ clean: * "regulator-coupled-with" property * @index: Index in phandles array * - * Returns the regulator_dev pointer parsed from DTS. If it has not been yet - * registered, returns NULL + * Return: Pointer to the &struct regulator_dev parsed from DTS, or %NULL if + * it has not yet been registered. */ struct regulator_dev *of_parse_coupled_regulator(struct regulator_dev *rdev, int index) @@ -735,31 +841,32 @@ static int is_supply_name(const char *name) return 0; } -/* +/** * of_regulator_bulk_get_all - get multiple regulator consumers * * @dev: Device to supply * @np: device node to search for consumers * @consumers: Configuration of consumers; clients are stored here. * - * @return number of regulators on success, an errno on failure. - * * This helper function allows drivers to get several regulator * consumers in one operation. If any of the regulators cannot be * acquired then any regulators that were allocated will be freed - * before returning to the caller. + * before returning to the caller, and @consumers will not be + * changed. + * + * Return: Number of regulators on success, or a negative error number + * on failure. */ int of_regulator_bulk_get_all(struct device *dev, struct device_node *np, struct regulator_bulk_data **consumers) { int num_consumers = 0; struct regulator *tmp; + struct regulator_bulk_data *_consumers = NULL; struct property *prop; int i, n = 0, ret; char name[64]; - *consumers = NULL; - /* * first pass: get numbers of xxx-supply * second pass: fill consumers @@ -769,7 +876,7 @@ restart: i = is_supply_name(prop->name); if (i == 0) continue; - if (!*consumers) { + if (!_consumers) { num_consumers++; continue; } else { @@ -777,28 +884,31 @@ restart: name[i] = '\0'; tmp = regulator_get(dev, name); if (IS_ERR(tmp)) { - ret = -EINVAL; + ret = PTR_ERR(tmp); goto error; } - (*consumers)[n].consumer = tmp; + _consumers[n].consumer = tmp; n++; continue; } } - if (*consumers) + if (_consumers) { + *consumers = _consumers; return num_consumers; + } if (num_consumers == 0) return 0; - *consumers = kmalloc_array(num_consumers, + _consumers = kmalloc_array(num_consumers, sizeof(struct regulator_bulk_data), GFP_KERNEL); - if (!*consumers) + if (!_consumers) return -ENOMEM; goto restart; error: while (--n >= 0) - regulator_put(consumers[n]->consumer); + regulator_put(_consumers[n].consumer); + kfree(_consumers); return ret; } EXPORT_SYMBOL_GPL(of_regulator_bulk_get_all); |