1 files changed, 61 insertions, 1 deletions

diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
index 1b7d64118e4d..cbe36b93639b 100644
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -91,6 +91,8 @@ struct regulator {
 
 static int _regulator_is_enabled(struct regulator_dev *rdev);
 static int _regulator_disable(struct regulator_dev *rdev);
+static int _regulator_enable(struct regulator_dev *rdev);
+static int _regulator_get_enable_time(struct regulator_dev *rdev);
 static int _regulator_get_voltage(struct regulator_dev *rdev);
 static int _regulator_get_current_limit(struct regulator_dev *rdev);
 static unsigned int _regulator_get_mode(struct regulator_dev *rdev);
@@ -358,7 +360,65 @@ static ssize_t regulator_state_show(struct device *dev,
 
 	return ret;
 }
-static DEVICE_ATTR(state, 0444, regulator_state_show, NULL);
+
+static ssize_t regulator_state_set(struct device *dev,
+		   struct device_attribute *attr, const char *buf, size_t count)
+{
+	struct regulator_dev *rdev = dev_get_drvdata(dev);
+	int ret;
+	bool enabled;
+
+	if ((*buf == 'E') || (*buf == 'e'))
+		enabled = true;
+	else if ((*buf == 'D') || (*buf == 'd'))
+		enabled = false;
+	else
+		return -EINVAL;
+
+	if ((_regulator_is_enabled(rdev) && enabled) ||
+		(!_regulator_is_enabled(rdev) && !enabled))
+		return count;
+
+	mutex_lock(&rdev->mutex);
+	if (enabled) {
+		int delay = 0;
+		if (!rdev->desc->ops->enable) {
+			ret = -EINVAL;
+			goto end;
+		}
+		ret = _regulator_get_enable_time(rdev);
+		if (ret >= 0)
+			delay = ret;
+		ret = rdev->desc->ops->enable(rdev);
+		if (ret < 0) {
+			rdev_warn(rdev, "enable() failed: %d\n", ret);
+			goto end;
+		}
+		if (delay >= 1000) {
+			mdelay(delay / 1000);
+			udelay(delay % 1000);
+		} else if (delay) {
+			udelay(delay);
+		}
+	} else {
+		if (!rdev->desc->ops->disable) {
+			ret = -EINVAL;
+			goto end;
+		}
+		ret = rdev->desc->ops->disable(rdev);
+		if (ret < 0) {
+			rdev_warn(rdev, "disable() failed: %d\n", ret);
+			goto end;
+		}
+	}
+
+end:
+	mutex_unlock(&rdev->mutex);
+	if (ret < 0)
+		return ret;
+	return count;
+}
+static DEVICE_ATTR(state, 0644, regulator_state_show, regulator_state_set);
 
 static ssize_t regulator_status_show(struct device *dev,
 				   struct device_attribute *attr, char *buf)