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path: root/drivers/regulator/core.c
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Diffstat (limited to 'drivers/regulator/core.c')
-rw-r--r--drivers/regulator/core.c386
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, &regulator_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(&regulator_list_mutex);
return regulator;
@@ -961,10 +1068,6 @@ void regulator_put(struct regulator *regulator)
mutex_lock(&regulator_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(&regulator->rdev->mutex);
- regulator->enabled = 0;
regulator->uA_load = 0;
ret = _regulator_force_disable(regulator->rdev);
mutex_unlock(&regulator->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(&regulator_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(&regulator_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, &regulator_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(&regulator_list_mutex);
+
+ return 0;
+}
+late_initcall(regulator_init_complete);