diff options
Diffstat (limited to 'drivers/regulator/core.c')
| -rw-r--r-- | drivers/regulator/core.c | 386 |
1 files changed, 316 insertions, 70 deletions
diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c index f511a406fca..01f7702a805 100644 --- a/drivers/regulator/core.c +++ b/drivers/regulator/core.c @@ -28,33 +28,7 @@ static DEFINE_MUTEX(regulator_list_mutex); static LIST_HEAD(regulator_list); static LIST_HEAD(regulator_map_list); - -/* - * struct regulator_dev - * - * Voltage / Current regulator class device. One for each regulator. - */ -struct regulator_dev { - struct regulator_desc *desc; - int use_count; - - /* lists we belong to */ - struct list_head list; /* list of all regulators */ - struct list_head slist; /* list of supplied regulators */ - - /* lists we own */ - struct list_head consumer_list; /* consumers we supply */ - struct list_head supply_list; /* regulators we supply */ - - struct blocking_notifier_head notifier; - struct mutex mutex; /* consumer lock */ - struct module *owner; - struct device dev; - struct regulation_constraints *constraints; - struct regulator_dev *supply; /* for tree */ - - void *reg_data; /* regulator_dev data */ -}; +static int has_full_constraints; /* * struct regulator_map @@ -79,7 +53,6 @@ struct regulator { int uA_load; int min_uV; int max_uV; - int enabled; /* count of client enables */ char *supply_name; struct device_attribute dev_attr; struct regulator_dev *rdev; @@ -312,6 +285,47 @@ static ssize_t regulator_state_show(struct device *dev, } static DEVICE_ATTR(state, 0444, regulator_state_show, NULL); +static ssize_t regulator_status_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct regulator_dev *rdev = dev_get_drvdata(dev); + int status; + char *label; + + status = rdev->desc->ops->get_status(rdev); + if (status < 0) + return status; + + switch (status) { + case REGULATOR_STATUS_OFF: + label = "off"; + break; + case REGULATOR_STATUS_ON: + label = "on"; + break; + case REGULATOR_STATUS_ERROR: + label = "error"; + break; + case REGULATOR_STATUS_FAST: + label = "fast"; + break; + case REGULATOR_STATUS_NORMAL: + label = "normal"; + break; + case REGULATOR_STATUS_IDLE: + label = "idle"; + break; + case REGULATOR_STATUS_STANDBY: + label = "standby"; + break; + default: + return -ERANGE; + } + + return sprintf(buf, "%s\n", label); +} +static DEVICE_ATTR(status, 0444, regulator_status_show, NULL); + static ssize_t regulator_min_uA_show(struct device *dev, struct device_attribute *attr, char *buf) { @@ -678,6 +692,73 @@ static int set_machine_constraints(struct regulator_dev *rdev, else name = "regulator"; + /* constrain machine-level voltage specs to fit + * the actual range supported by this regulator. + */ + if (ops->list_voltage && rdev->desc->n_voltages) { + int count = rdev->desc->n_voltages; + int i; + int min_uV = INT_MAX; + int max_uV = INT_MIN; + int cmin = constraints->min_uV; + int cmax = constraints->max_uV; + + /* it's safe to autoconfigure fixed-voltage supplies */ + if (count == 1 && !cmin) { + cmin = INT_MIN; + cmax = INT_MAX; + } + + /* voltage constraints are optional */ + if ((cmin == 0) && (cmax == 0)) + goto out; + + /* else require explicit machine-level constraints */ + if (cmin <= 0 || cmax <= 0 || cmax < cmin) { + pr_err("%s: %s '%s' voltage constraints\n", + __func__, "invalid", name); + ret = -EINVAL; + goto out; + } + + /* initial: [cmin..cmax] valid, [min_uV..max_uV] not */ + for (i = 0; i < count; i++) { + int value; + + value = ops->list_voltage(rdev, i); + if (value <= 0) + continue; + + /* maybe adjust [min_uV..max_uV] */ + if (value >= cmin && value < min_uV) + min_uV = value; + if (value <= cmax && value > max_uV) + max_uV = value; + } + + /* final: [min_uV..max_uV] valid iff constraints valid */ + if (max_uV < min_uV) { + pr_err("%s: %s '%s' voltage constraints\n", + __func__, "unsupportable", name); + ret = -EINVAL; + goto out; + } + + /* use regulator's subset of machine constraints */ + if (constraints->min_uV < min_uV) { + pr_debug("%s: override '%s' %s, %d -> %d\n", + __func__, name, "min_uV", + constraints->min_uV, min_uV); + constraints->min_uV = min_uV; + } + if (constraints->max_uV > max_uV) { + pr_debug("%s: override '%s' %s, %d -> %d\n", + __func__, name, "max_uV", + constraints->max_uV, max_uV); + constraints->max_uV = max_uV; + } + } + rdev->constraints = constraints; /* do we need to apply the constraint voltage */ @@ -695,10 +776,6 @@ static int set_machine_constraints(struct regulator_dev *rdev, } } - /* are we enabled at boot time by firmware / bootloader */ - if (rdev->constraints->boot_on) - rdev->use_count = 1; - /* do we need to setup our suspend state */ if (constraints->initial_state) { ret = suspend_prepare(rdev, constraints->initial_state); @@ -710,11 +787,27 @@ static int set_machine_constraints(struct regulator_dev *rdev, } } - /* if always_on is set then turn the regulator on if it's not - * already on. */ - if (constraints->always_on && ops->enable && - ((ops->is_enabled && !ops->is_enabled(rdev)) || - (!ops->is_enabled && !constraints->boot_on))) { + if (constraints->initial_mode) { + if (!ops->set_mode) { + printk(KERN_ERR "%s: no set_mode operation for %s\n", + __func__, name); + ret = -EINVAL; + goto out; + } + + ret = ops->set_mode(rdev, constraints->initial_mode); + if (ret < 0) { + printk(KERN_ERR + "%s: failed to set initial mode for %s: %d\n", + __func__, name, ret); + goto out; + } + } + + /* If the constraints say the regulator should be on at this point + * and we have control then make sure it is enabled. + */ + if ((constraints->always_on || constraints->boot_on) && ops->enable) { ret = ops->enable(rdev); if (ret < 0) { printk(KERN_ERR "%s: failed to enable %s\n", @@ -817,6 +910,19 @@ static void unset_consumer_device_supply(struct regulator_dev *rdev, } } +static void unset_regulator_supplies(struct regulator_dev *rdev) +{ + struct regulator_map *node, *n; + + list_for_each_entry_safe(node, n, ®ulator_map_list, list) { + if (rdev == node->regulator) { + list_del(&node->list); + kfree(node); + return; + } + } +} + #define REG_STR_SIZE 32 static struct regulator *create_regulator(struct regulator_dev *rdev, @@ -898,9 +1004,12 @@ overflow_err: * @id: Supply name or regulator ID. * * Returns a struct regulator corresponding to the regulator producer, - * or IS_ERR() condition containing errno. Use of supply names - * configured via regulator_set_device_supply() is strongly - * encouraged. + * or IS_ERR() condition containing errno. + * + * 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(struct device *dev, const char *id) { @@ -922,8 +1031,6 @@ struct regulator *regulator_get(struct device *dev, const char *id) goto found; } } - printk(KERN_ERR "regulator: Unable to get requested regulator: %s\n", - id); mutex_unlock(®ulator_list_mutex); return regulator; @@ -961,10 +1068,6 @@ void regulator_put(struct regulator *regulator) mutex_lock(®ulator_list_mutex); rdev = regulator->rdev; - if (WARN(regulator->enabled, "Releasing supply %s while enabled\n", - regulator->supply_name)) - _regulator_disable(rdev); - /* remove any sysfs entries */ if (regulator->dev) { sysfs_remove_link(&rdev->dev.kobj, regulator->supply_name); @@ -1039,12 +1142,7 @@ int regulator_enable(struct regulator *regulator) int ret = 0; mutex_lock(&rdev->mutex); - if (regulator->enabled == 0) - ret = _regulator_enable(rdev); - else if (regulator->enabled < 0) - ret = -EIO; - if (ret == 0) - regulator->enabled++; + ret = _regulator_enable(rdev); mutex_unlock(&rdev->mutex); return ret; } @@ -1055,6 +1153,11 @@ static int _regulator_disable(struct regulator_dev *rdev) { int ret = 0; + if (WARN(rdev->use_count <= 0, + "unbalanced disables for %s\n", + rdev->desc->name)) + return -EIO; + /* are we the last user and permitted to disable ? */ if (rdev->use_count == 1 && !rdev->constraints->always_on) { @@ -1103,16 +1206,7 @@ int regulator_disable(struct regulator *regulator) int ret = 0; mutex_lock(&rdev->mutex); - if (regulator->enabled == 1) { - ret = _regulator_disable(rdev); - if (ret == 0) - regulator->uA_load = 0; - } else if (WARN(regulator->enabled <= 0, - "unbalanced disables for supply %s\n", - regulator->supply_name)) - ret = -EIO; - if (ret == 0) - regulator->enabled--; + ret = _regulator_disable(rdev); mutex_unlock(&rdev->mutex); return ret; } @@ -1159,7 +1253,6 @@ int regulator_force_disable(struct regulator *regulator) int ret; mutex_lock(®ulator->rdev->mutex); - regulator->enabled = 0; regulator->uA_load = 0; ret = _regulator_force_disable(regulator->rdev); mutex_unlock(®ulator->rdev->mutex); @@ -1204,6 +1297,56 @@ int regulator_is_enabled(struct regulator *regulator) EXPORT_SYMBOL_GPL(regulator_is_enabled); /** + * regulator_count_voltages - count regulator_list_voltage() selectors + * @regulator: regulator source + * + * Returns number of selectors, or negative errno. Selectors are + * numbered starting at zero, and typically correspond to bitfields + * in hardware registers. + */ +int regulator_count_voltages(struct regulator *regulator) +{ + struct regulator_dev *rdev = regulator->rdev; + + return rdev->desc->n_voltages ? : -EINVAL; +} +EXPORT_SYMBOL_GPL(regulator_count_voltages); + +/** + * regulator_list_voltage - enumerate supported voltages + * @regulator: regulator source + * @selector: identify voltage to list + * Context: can sleep + * + * Returns a voltage that can be passed to @regulator_set_voltage(), + * zero if this selector code can't be used on this sytem, or a + * negative errno. + */ +int regulator_list_voltage(struct regulator *regulator, unsigned selector) +{ + struct regulator_dev *rdev = regulator->rdev; + struct regulator_ops *ops = rdev->desc->ops; + int ret; + + if (!ops->list_voltage || selector >= rdev->desc->n_voltages) + return -EINVAL; + + mutex_lock(&rdev->mutex); + ret = ops->list_voltage(rdev, selector); + mutex_unlock(&rdev->mutex); + + if (ret > 0) { + if (ret < rdev->constraints->min_uV) + ret = 0; + else if (ret > rdev->constraints->max_uV) + ret = 0; + } + + return ret; +} +EXPORT_SYMBOL_GPL(regulator_list_voltage); + +/** * regulator_set_voltage - set regulator output voltage * @regulator: regulator source * @min_uV: Minimum required voltage in uV @@ -1243,6 +1386,7 @@ int regulator_set_voltage(struct regulator *regulator, int min_uV, int max_uV) ret = rdev->desc->ops->set_voltage(rdev, min_uV, max_uV); out: + _notifier_call_chain(rdev, REGULATOR_EVENT_VOLTAGE_CHANGE, NULL); mutex_unlock(&rdev->mutex); return ret; } @@ -1543,20 +1687,23 @@ int regulator_unregister_notifier(struct regulator *regulator, } EXPORT_SYMBOL_GPL(regulator_unregister_notifier); -/* notify regulator consumers and downstream regulator consumers */ +/* notify regulator consumers and downstream regulator consumers. + * Note mutex must be held by caller. + */ static void _notifier_call_chain(struct regulator_dev *rdev, unsigned long event, void *data) { struct regulator_dev *_rdev; /* call rdev chain first */ - mutex_lock(&rdev->mutex); blocking_notifier_call_chain(&rdev->notifier, event, NULL); - mutex_unlock(&rdev->mutex); /* now notify regulator we supply */ - list_for_each_entry(_rdev, &rdev->supply_list, slist) - _notifier_call_chain(_rdev, event, data); + list_for_each_entry(_rdev, &rdev->supply_list, slist) { + mutex_lock(&_rdev->mutex); + _notifier_call_chain(_rdev, event, data); + mutex_unlock(&_rdev->mutex); + } } /** @@ -1703,6 +1850,7 @@ EXPORT_SYMBOL_GPL(regulator_bulk_free); * * Called by regulator drivers to notify clients a regulator event has * occurred. We also notify regulator clients downstream. + * Note lock must be held by caller. */ int regulator_notifier_call_chain(struct regulator_dev *rdev, unsigned long event, void *data) @@ -1744,6 +1892,11 @@ static int add_regulator_attributes(struct regulator_dev *rdev) if (status < 0) return status; } + if (ops->get_status) { + status = device_create_file(dev, &dev_attr_status); + if (status < 0) + return status; + } /* some attributes are type-specific */ if (rdev->desc->type == REGULATOR_CURRENT) { @@ -1828,17 +1981,18 @@ static int add_regulator_attributes(struct regulator_dev *rdev) * regulator_register - register regulator * @regulator_desc: regulator to register * @dev: struct device for the regulator + * @init_data: platform provided init data, passed through by driver * @driver_data: private regulator data * * Called by regulator drivers to register a regulator. * Returns 0 on success. */ struct regulator_dev *regulator_register(struct regulator_desc *regulator_desc, - struct device *dev, void *driver_data) + struct device *dev, struct regulator_init_data *init_data, + void *driver_data) { static atomic_t regulator_no = ATOMIC_INIT(0); struct regulator_dev *rdev; - struct regulator_init_data *init_data = dev->platform_data; int ret, i; if (regulator_desc == NULL) @@ -1945,6 +2099,7 @@ void regulator_unregister(struct regulator_dev *rdev) return; mutex_lock(®ulator_list_mutex); + unset_regulator_supplies(rdev); list_del(&rdev->list); if (rdev->supply) sysfs_remove_link(&rdev->dev.kobj, "supply"); @@ -1989,6 +2144,23 @@ out: EXPORT_SYMBOL_GPL(regulator_suspend_prepare); /** + * regulator_has_full_constraints - the system has fully specified constraints + * + * Calling this function will cause the regulator API to disable all + * regulators which have a zero use count and don't have an always_on + * constraint in a late_initcall. + * + * The intention is that this will become the default behaviour in a + * future kernel release so users are encouraged to use this facility + * now. + */ +void regulator_has_full_constraints(void) +{ + has_full_constraints = 1; +} +EXPORT_SYMBOL_GPL(regulator_has_full_constraints); + +/** * rdev_get_drvdata - get rdev regulator driver data * @rdev: regulator * @@ -2055,3 +2227,77 @@ static int __init regulator_init(void) /* init early to allow our consumers to complete system booting */ core_initcall(regulator_init); + +static int __init regulator_init_complete(void) +{ + struct regulator_dev *rdev; + struct regulator_ops *ops; + struct regulation_constraints *c; + int enabled, ret; + const char *name; + + mutex_lock(®ulator_list_mutex); + + /* If we have a full configuration then disable any regulators + * which are not in use or always_on. This will become the + * default behaviour in the future. + */ + list_for_each_entry(rdev, ®ulator_list, list) { + ops = rdev->desc->ops; + c = rdev->constraints; + + if (c->name) + name = c->name; + else if (rdev->desc->name) + name = rdev->desc->name; + else + name = "regulator"; + + if (!ops->disable || c->always_on) + continue; + + mutex_lock(&rdev->mutex); + + if (rdev->use_count) + goto unlock; + + /* If we can't read the status assume it's on. */ + if (ops->is_enabled) + enabled = ops->is_enabled(rdev); + else + enabled = 1; + + if (!enabled) + goto unlock; + + if (has_full_constraints) { + /* We log since this may kill the system if it + * goes wrong. */ + printk(KERN_INFO "%s: disabling %s\n", + __func__, name); + ret = ops->disable(rdev); + if (ret != 0) { + printk(KERN_ERR + "%s: couldn't disable %s: %d\n", + __func__, name, ret); + } + } else { + /* The intention is that in future we will + * assume that full constraints are provided + * so warn even if we aren't going to do + * anything here. + */ + printk(KERN_WARNING + "%s: incomplete constraints, leaving %s on\n", + __func__, name); + } + +unlock: + mutex_unlock(&rdev->mutex); + } + + mutex_unlock(®ulator_list_mutex); + + return 0; +} +late_initcall(regulator_init_complete); |