regulator: enable supply regulator only when use count is zero

[pandora-kernel.git] / drivers / regulator / core.c

diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
index f1d10c9..c577c6d 100644 (file)
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -1052,7 +1052,6 @@ static struct regulator *create_regulator(struct regulator_dev *rdev,
                        printk(KERN_WARNING
                               "%s: could not add device link %s err %d\n",
                               __func__, dev->kobj.name, err);
-                       device_remove_file(dev, &regulator->dev_attr);
                        goto link_name_err;
                }
        }
@@ -1268,13 +1267,17 @@ static int _regulator_enable(struct regulator_dev *rdev)
 {
        int ret, delay;
 
-       /* do we need to enable the supply regulator first */
-       if (rdev->supply) {
-               ret = _regulator_enable(rdev->supply);
-               if (ret < 0) {
-                       printk(KERN_ERR "%s: failed to enable %s: %d\n",
-                              __func__, rdev_get_name(rdev), ret);
-                       return ret;
+       if (rdev->use_count == 0) {
+               /* do we need to enable the supply regulator first */
+               if (rdev->supply) {
+                       mutex_lock(&rdev->supply->mutex);
+                       ret = _regulator_enable(rdev->supply);
+                       mutex_unlock(&rdev->supply->mutex);
+                       if (ret < 0) {
+                               printk(KERN_ERR "%s: failed to enable %s: %d\n",
+                                      __func__, rdev_get_name(rdev), ret);
+                               return ret;
+                       }
                }
        }
 
@@ -1313,10 +1316,12 @@ static int _regulator_enable(struct regulator_dev *rdev)
                        if (ret < 0)
                                return ret;
 
-                       if (delay >= 1000)
+                       if (delay >= 1000) {
                                mdelay(delay / 1000);
-                       else if (delay)
+                               udelay(delay % 1000);
+                       } else if (delay) {
                                udelay(delay);
+                       }
 
                } else if (ret < 0) {
                        printk(KERN_ERR "%s: is_enabled() failed for %s: %d\n",
@@ -1359,6 +1364,7 @@ static int _regulator_disable(struct regulator_dev *rdev,
                struct regulator_dev **supply_rdev_ptr)
 {
        int ret = 0;
+       *supply_rdev_ptr = NULL;
 
        if (WARN(rdev->use_count <= 0,
                        "unbalanced disables for %s\n",
@@ -2346,6 +2352,7 @@ struct regulator_dev *regulator_register(struct regulator_desc *regulator_desc,
        if (init_data->supply_regulator && init_data->supply_regulator_dev) {
                dev_err(dev,
                        "Supply regulator specified by both name and dev\n");
+               ret = -EINVAL;
                goto scrub;
        }
 
@@ -2364,6 +2371,7 @@ struct regulator_dev *regulator_register(struct regulator_desc *regulator_desc,
                if (!found) {
                        dev_err(dev, "Failed to find supply %s\n",
                                init_data->supply_regulator);
+                       ret = -ENODEV;
                        goto scrub;
                }