diff options
Diffstat (limited to 'drivers/regulator/of_regulator.c')
-rw-r--r-- | drivers/regulator/of_regulator.c | 110 |
1 files changed, 109 insertions, 1 deletions
diff --git a/drivers/regulator/of_regulator.c b/drivers/regulator/of_regulator.c index cec8c3647a00..d5dd7a9e577b 100644 --- a/drivers/regulator/of_regulator.c +++ b/drivers/regulator/of_regulator.c @@ -552,7 +552,75 @@ 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) { + regnode = of_get_child_regulator(child, prop_name); + if (regnode) + goto err_node_put; + } else { + 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) { + 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; + } + return regnode; +} + +static struct regulator_dev *of_find_regulator_by_node(struct device_node *np) { struct device *dev; @@ -561,6 +629,46 @@ 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. */ |