1 files changed, 68 insertions, 16 deletions

diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
index 5c4829cba6a6..278584302f2d 100644
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -199,8 +199,11 @@ static int regulator_check_consumers(struct regulator_dev *rdev,
 			*min_uV = regulator->min_uV;
 	}
 
-	if (*min_uV > *max_uV)
+	if (*min_uV > *max_uV) {
+		dev_err(regulator->dev, "Restricting voltage, %u-%uuV\n",
+			regulator->min_uV, regulator->max_uV);
 		return -EINVAL;
+	}
 
 	return 0;
 }
@@ -880,7 +883,9 @@ static int machine_constraints_voltage(struct regulator_dev *rdev,
 
 		/* final: [min_uV..max_uV] valid iff constraints valid */
 		if (max_uV < min_uV) {
-			rdev_err(rdev, "unsupportable voltage constraints\n");
+			rdev_err(rdev,
+				 "unsupportable voltage constraints %u-%uuV\n",
+				 min_uV, max_uV);
 			return -EINVAL;
 		}
 
@@ -1381,22 +1386,14 @@ struct regulator *regulator_get_exclusive(struct device *dev, const char *id)
 }
 EXPORT_SYMBOL_GPL(regulator_get_exclusive);
 
-/**
- * regulator_put - "free" the regulator source
- * @regulator: regulator source
- *
- * Note: drivers must ensure that all regulator_enable calls made on this
- * regulator source are balanced by regulator_disable calls prior to calling
- * this function.
- */
-void regulator_put(struct regulator *regulator)
+/* Locks held by regulator_put() */
+static void _regulator_put(struct regulator *regulator)
 {
 	struct regulator_dev *rdev;
 
 	if (regulator == NULL || IS_ERR(regulator))
 		return;
 
-	mutex_lock(&regulator_list_mutex);
 	rdev = regulator->rdev;
 
 	debugfs_remove_recursive(regulator->debugfs);
@@ -1412,6 +1409,20 @@ void regulator_put(struct regulator *regulator)
 	rdev->exclusive = 0;
 
 	module_put(rdev->owner);
+}
+
+/**
+ * regulator_put - "free" the regulator source
+ * @regulator: regulator source
+ *
+ * Note: drivers must ensure that all regulator_enable calls made on this
+ * regulator source are balanced by regulator_disable calls prior to calling
+ * this function.
+ */
+void regulator_put(struct regulator *regulator)
+{
+	mutex_lock(&regulator_list_mutex);
+	_regulator_put(regulator);
 	mutex_unlock(&regulator_list_mutex);
 }
 EXPORT_SYMBOL_GPL(regulator_put);
@@ -1861,6 +1872,34 @@ int regulator_is_enabled(struct regulator *regulator)
 EXPORT_SYMBOL_GPL(regulator_is_enabled);
 
 /**
+ * regulator_can_change_voltage - check if regulator can change voltage
+ * @regulator: regulator source
+ *
+ * Returns positive if the regulator driver backing the source/client
+ * can change its voltage, false otherwise. Usefull for detecting fixed
+ * or dummy regulators and disabling voltage change logic in the client
+ * driver.
+ */
+int regulator_can_change_voltage(struct regulator *regulator)
+{
+	struct regulator_dev	*rdev = regulator->rdev;
+
+	if (rdev->constraints &&
+	    (rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE)) {
+		if (rdev->desc->n_voltages - rdev->desc->linear_min_sel > 1)
+			return 1;
+
+		if (rdev->desc->continuous_voltage_range &&
+		    rdev->constraints->min_uV && rdev->constraints->max_uV &&
+		    rdev->constraints->min_uV != rdev->constraints->max_uV)
+			return 1;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(regulator_can_change_voltage);
+
+/**
  * regulator_count_voltages - count regulator_list_voltage() selectors
  * @regulator: regulator source
  *
@@ -1891,6 +1930,10 @@ int regulator_list_voltage_linear(struct regulator_dev *rdev,
 {
 	if (selector >= rdev->desc->n_voltages)
 		return -EINVAL;
+	if (selector < rdev->desc->linear_min_sel)
+		return 0;
+
+	selector -= rdev->desc->linear_min_sel;
 
 	return rdev->desc->min_uV + (rdev->desc->uV_step * selector);
 }
@@ -1974,11 +2017,16 @@ int regulator_is_supported_voltage(struct regulator *regulator,
 	if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE)) {
 		ret = regulator_get_voltage(regulator);
 		if (ret >= 0)
-			return (min_uV >= ret && ret <= max_uV);
+			return (min_uV <= ret && ret <= max_uV);
 		else
 			return ret;
 	}
 
+	/* Any voltage within constrains range is fine? */
+	if (rdev->desc->continuous_voltage_range)
+		return min_uV >= rdev->constraints->min_uV &&
+				max_uV <= rdev->constraints->max_uV;
+
 	ret = regulator_count_voltages(regulator);
 	if (ret < 0)
 		return ret;
@@ -2114,6 +2162,8 @@ int regulator_map_voltage_linear(struct regulator_dev *rdev,
 	if (ret < 0)
 		return ret;
 
+	ret += rdev->desc->linear_min_sel;
+
 	/* Map back into a voltage to verify we're still in bounds */
 	voltage = rdev->desc->ops->list_voltage(rdev, ret);
 	if (voltage < min_uV || voltage > max_uV)
@@ -3271,7 +3321,8 @@ static void rdev_init_debugfs(struct regulator_dev *rdev)
  * @config: runtime configuration for regulator
  *
  * Called by regulator drivers to register a regulator.
- * Returns 0 on success.
+ * Returns a valid pointer to struct regulator_dev on success
+ * or an ERR_PTR() on error.
  */
 struct regulator_dev *
 regulator_register(const struct regulator_desc *regulator_desc,
@@ -3365,7 +3416,7 @@ regulator_register(const struct regulator_desc *regulator_desc,
 		if (ret != 0) {
 			rdev_err(rdev, "Failed to request enable GPIO%d: %d\n",
 				 config->ena_gpio, ret);
-			goto clean;
+			goto wash;
 		}
 
 		rdev->ena_gpio = config->ena_gpio;
@@ -3445,10 +3496,11 @@ unset_supplies:
 
 scrub:
 	if (rdev->supply)
-		regulator_put(rdev->supply);
+		_regulator_put(rdev->supply);
 	if (rdev->ena_gpio)
 		gpio_free(rdev->ena_gpio);
 	kfree(rdev->constraints);
+wash:
 	device_unregister(&rdev->dev);
 	/* device core frees rdev */
 	rdev = ERR_PTR(ret);