regulator: improved mode error checks

[safe/jmp/linux-2.6] / drivers / regulator / core.c

diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
index 9a6757d..686dfa9 100644 (file)
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -79,7 +79,7 @@ struct regulator {
        int uA_load;
        int min_uV;
        int max_uV;
-       int enabled; /* client has called enabled */
+       int enabled; /* count of client enables */
        char *supply_name;
        struct device_attribute dev_attr;
        struct regulator_dev *rdev;
@@ -174,6 +174,16 @@ static int regulator_check_current_limit(struct regulator_dev *rdev,
 /* operating mode constraint check */
 static int regulator_check_mode(struct regulator_dev *rdev, int mode)
 {
+       switch (mode) {
+       case REGULATOR_MODE_FAST:
+       case REGULATOR_MODE_NORMAL:
+       case REGULATOR_MODE_IDLE:
+       case REGULATOR_MODE_STANDBY:
+               break;
+       default:
+               return -EINVAL;
+       }
+
        if (!rdev->constraints) {
                printk(KERN_ERR "%s: no constraints for %s\n", __func__,
                       rdev->desc->name);
@@ -241,6 +251,22 @@ static ssize_t regulator_uA_show(struct device *dev,
        return sprintf(buf, "%d\n", _regulator_get_current_limit(rdev));
 }
 
+static ssize_t regulator_name_show(struct device *dev,
+                            struct device_attribute *attr, char *buf)
+{
+       struct regulator_dev *rdev = dev_get_drvdata(dev);
+       const char *name;
+
+       if (rdev->constraints->name)
+               name = rdev->constraints->name;
+       else if (rdev->desc->name)
+               name = rdev->desc->name;
+       else
+               name = "";
+
+       return sprintf(buf, "%s\n", name);
+}
+
 static ssize_t regulator_opmode_show(struct device *dev,
                                    struct device_attribute *attr, char *buf)
 {
@@ -473,7 +499,9 @@ static ssize_t regulator_suspend_standby_state_show(struct device *dev,
        else
                return sprintf(buf, "disabled\n");
 }
+
 static struct device_attribute regulator_dev_attrs[] = {
+       __ATTR(name, 0444, regulator_name_show, NULL),
        __ATTR(microvolts, 0444, regulator_uV_show, NULL),
        __ATTR(microamps, 0444, regulator_uA_show, NULL),
        __ATTR(opmode, 0444, regulator_opmode_show, NULL),
@@ -945,16 +973,13 @@ void regulator_put(struct regulator *regulator)
        if (regulator == NULL || IS_ERR(regulator))
                return;
 
-       if (regulator->enabled) {
-               printk(KERN_WARNING "Releasing supply %s while enabled\n",
-                      regulator->supply_name);
-               WARN_ON(regulator->enabled);
-               regulator_disable(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);
@@ -1024,21 +1049,17 @@ static int _regulator_enable(struct regulator_dev *rdev)
  */
 int regulator_enable(struct regulator *regulator)
 {
-       int ret;
-
-       if (regulator->enabled) {
-               printk(KERN_CRIT "Regulator %s already enabled\n",
-                      regulator->supply_name);
-               WARN_ON(regulator->enabled);
-               return 0;
-       }
+       struct regulator_dev *rdev = regulator->rdev;
+       int ret = 0;
 
-       mutex_lock(&regulator->rdev->mutex);
-       regulator->enabled = 1;
-       ret = _regulator_enable(regulator->rdev);
-       if (ret != 0)
-               regulator->enabled = 0;
-       mutex_unlock(&regulator->rdev->mutex);
+       mutex_lock(&rdev->mutex);
+       if (regulator->enabled == 0)
+               ret = _regulator_enable(rdev);
+       else if (regulator->enabled < 0)
+               ret = -EIO;
+       if (ret == 0)
+               regulator->enabled++;
+       mutex_unlock(&rdev->mutex);
        return ret;
 }
 EXPORT_SYMBOL_GPL(regulator_enable);
@@ -1090,19 +1111,21 @@ static int _regulator_disable(struct regulator_dev *rdev)
  */
 int regulator_disable(struct regulator *regulator)
 {
-       int ret;
-
-       if (!regulator->enabled) {
-               printk(KERN_ERR "%s: not in use by this consumer\n",
-                       __func__);
-               return 0;
-       }
+       struct regulator_dev *rdev = regulator->rdev;
+       int ret = 0;
 
-       mutex_lock(&regulator->rdev->mutex);
-       regulator->enabled = 0;
-       regulator->uA_load = 0;
-       ret = _regulator_disable(regulator->rdev);
-       mutex_unlock(&regulator->rdev->mutex);
+       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--;
+       mutex_unlock(&rdev->mutex);
        return ret;
 }
 EXPORT_SYMBOL_GPL(regulator_disable);
@@ -1178,7 +1201,13 @@ out:
  * regulator_is_enabled - is the regulator output enabled
  * @regulator: regulator source
  *
- * Returns zero for disabled otherwise return number of enable requests.
+ * Returns positive if the regulator driver backing the source/client
+ * has requested that the device be enabled, zero if it hasn't, else a
+ * negative errno code.
+ *
+ * Note that the device backing this regulator handle can have multiple
+ * users, so it might be enabled even if regulator_enable() was never
+ * called for this particular source.
  */
 int regulator_is_enabled(struct regulator *regulator)
 {
@@ -1475,7 +1504,8 @@ int regulator_set_optimum_mode(struct regulator *regulator, int uA_load)
        mode = rdev->desc->ops->get_optimum_mode(rdev,
                                                 input_uV, output_uV,
                                                 total_uA_load);
-       if (ret <= 0) {
+       ret = regulator_check_mode(rdev, mode);
+       if (ret < 0) {
                printk(KERN_ERR "%s: failed to get optimum mode for %s @"
                        " %d uA %d -> %d uV\n", __func__, rdev->desc->name,
                        total_uA_load, input_uV, output_uV);
@@ -1483,7 +1513,7 @@ int regulator_set_optimum_mode(struct regulator *regulator, int uA_load)
        }
 
        ret = rdev->desc->ops->set_mode(rdev, mode);
-       if (ret <= 0) {
+       if (ret < 0) {
                printk(KERN_ERR "%s: failed to set optimum mode %x for %s\n",
                        __func__, mode, rdev->desc->name);
                goto out;
@@ -1761,8 +1791,8 @@ struct regulator_dev *regulator_register(struct regulator_desc *regulator_desc,
        /* register with sysfs */
        rdev->dev.class = &regulator_class;
        rdev->dev.parent = dev;
-       snprintf(rdev->dev.bus_id, sizeof(rdev->dev.bus_id),
-                "regulator.%d", atomic_inc_return(&regulator_no) - 1);
+       dev_set_name(&rdev->dev, "regulator.%d",
+                    atomic_inc_return(&regulator_no) - 1);
        ret = device_register(&rdev->dev);
        if (ret != 0) {
                kfree(rdev);