Merge remote-tracking branches 'regulator/topic/s2mpa01', 'regulator/topic/supplies...
[sfrench/cifs-2.6.git] / drivers / regulator / core.c
index bcf67abd1cd2d66265e20b7953faf23b4d022d20..53d4fc70dbd0981cdb73eabdc815346c25963b6b 100644 (file)
@@ -1455,12 +1455,14 @@ static struct regulator_dev *regulator_lookup_by_name(const char *name)
  * lookup could succeed in the future.
  *
  * If successful, returns a struct regulator_dev that corresponds to the name
- * @supply and with the embedded struct device refcount incremented by one,
- * or NULL on failure. The refcount must be dropped by calling put_device().
+ * @supply and with the embedded struct device refcount incremented by one.
+ * The refcount must be dropped by calling put_device().
+ * On failure one of the following ERR-PTR-encoded values is returned:
+ * -ENODEV if lookup fails permanently, -EPROBE_DEFER if lookup could succeed
+ * in the future.
  */
 static struct regulator_dev *regulator_dev_lookup(struct device *dev,
-                                                 const char *supply,
-                                                 int *ret)
+                                                 const char *supply)
 {
        struct regulator_dev *r;
        struct device_node *node;
@@ -1476,16 +1478,12 @@ static struct regulator_dev *regulator_dev_lookup(struct device *dev,
                        r = of_find_regulator_by_node(node);
                        if (r)
                                return r;
-                       *ret = -EPROBE_DEFER;
-                       return NULL;
-               } else {
+
                        /*
-                        * If we couldn't even get the node then it's
-                        * not just that the device didn't register
-                        * yet, there's no node and we'll never
-                        * succeed.
+                        * We have a node, but there is no device.
+                        * assume it has not registered yet.
                         */
-                       *ret = -ENODEV;
+                       return ERR_PTR(-EPROBE_DEFER);
                }
        }
 
@@ -1506,13 +1504,16 @@ static struct regulator_dev *regulator_dev_lookup(struct device *dev,
 
                if (strcmp(map->supply, supply) == 0 &&
                    get_device(&map->regulator->dev)) {
-                       mutex_unlock(&regulator_list_mutex);
-                       return map->regulator;
+                       r = map->regulator;
+                       break;
                }
        }
        mutex_unlock(&regulator_list_mutex);
 
-       return NULL;
+       if (r)
+               return r;
+
+       return ERR_PTR(-ENODEV);
 }
 
 static int regulator_resolve_supply(struct regulator_dev *rdev)
@@ -1529,8 +1530,10 @@ static int regulator_resolve_supply(struct regulator_dev *rdev)
        if (rdev->supply)
                return 0;
 
-       r = regulator_dev_lookup(dev, rdev->supply_name, &ret);
-       if (!r) {
+       r = regulator_dev_lookup(dev, rdev->supply_name);
+       if (IS_ERR(r)) {
+               ret = PTR_ERR(r);
+
                if (ret == -ENODEV) {
                        /*
                         * No supply was specified for this regulator and
@@ -1593,69 +1596,72 @@ static int regulator_resolve_supply(struct regulator_dev *rdev)
 }
 
 /* Internal regulator request function */
-static struct regulator *_regulator_get(struct device *dev, const char *id,
-                                       bool exclusive, bool allow_dummy)
+struct regulator *_regulator_get(struct device *dev, const char *id,
+                                enum regulator_get_type get_type)
 {
        struct regulator_dev *rdev;
-       struct regulator *regulator = ERR_PTR(-EPROBE_DEFER);
-       const char *devname = NULL;
+       struct regulator *regulator;
+       const char *devname = dev ? dev_name(dev) : "deviceless";
        int ret;
 
+       if (get_type >= MAX_GET_TYPE) {
+               dev_err(dev, "invalid type %d in %s\n", get_type, __func__);
+               return ERR_PTR(-EINVAL);
+       }
+
        if (id == NULL) {
                pr_err("get() with no identifier\n");
                return ERR_PTR(-EINVAL);
        }
 
-       if (dev)
-               devname = dev_name(dev);
-
-       if (have_full_constraints())
-               ret = -ENODEV;
-       else
-               ret = -EPROBE_DEFER;
-
-       rdev = regulator_dev_lookup(dev, id, &ret);
-       if (rdev)
-               goto found;
+       rdev = regulator_dev_lookup(dev, id);
+       if (IS_ERR(rdev)) {
+               ret = PTR_ERR(rdev);
 
-       regulator = ERR_PTR(ret);
+               /*
+                * If regulator_dev_lookup() fails with error other
+                * than -ENODEV our job here is done, we simply return it.
+                */
+               if (ret != -ENODEV)
+                       return ERR_PTR(ret);
 
-       /*
-        * If we have return value from dev_lookup fail, we do not expect to
-        * succeed, so, quit with appropriate error value
-        */
-       if (ret && ret != -ENODEV)
-               return regulator;
+               if (!have_full_constraints()) {
+                       dev_warn(dev,
+                                "incomplete constraints, dummy supplies not allowed\n");
+                       return ERR_PTR(-ENODEV);
+               }
 
-       if (!devname)
-               devname = "deviceless";
+               switch (get_type) {
+               case NORMAL_GET:
+                       /*
+                        * Assume that a regulator is physically present and
+                        * enabled, even if it isn't hooked up, and just
+                        * provide a dummy.
+                        */
+                       dev_warn(dev,
+                                "%s supply %s not found, using dummy regulator\n",
+                                devname, id);
+                       rdev = dummy_regulator_rdev;
+                       get_device(&rdev->dev);
+                       break;
 
-       /*
-        * Assume that a regulator is physically present and enabled
-        * even if it isn't hooked up and just provide a dummy.
-        */
-       if (have_full_constraints() && allow_dummy) {
-               pr_warn("%s supply %s not found, using dummy regulator\n",
-                       devname, id);
+               case EXCLUSIVE_GET:
+                       dev_warn(dev,
+                                "dummy supplies not allowed for exclusive requests\n");
+                       /* fall through */
 
-               rdev = dummy_regulator_rdev;
-               get_device(&rdev->dev);
-               goto found;
-       /* Don't log an error when called from regulator_get_optional() */
-       } else if (!have_full_constraints() || exclusive) {
-               dev_warn(dev, "dummy supplies not allowed\n");
+               default:
+                       return ERR_PTR(-ENODEV);
+               }
        }
 
-       return regulator;
-
-found:
        if (rdev->exclusive) {
                regulator = ERR_PTR(-EPERM);
                put_device(&rdev->dev);
                return regulator;
        }
 
-       if (exclusive && rdev->open_count) {
+       if (get_type == EXCLUSIVE_GET && rdev->open_count) {
                regulator = ERR_PTR(-EBUSY);
                put_device(&rdev->dev);
                return regulator;
@@ -1669,6 +1675,7 @@ found:
        }
 
        if (!try_module_get(rdev->owner)) {
+               regulator = ERR_PTR(-EPROBE_DEFER);
                put_device(&rdev->dev);
                return regulator;
        }
@@ -1682,7 +1689,7 @@ found:
        }
 
        rdev->open_count++;
-       if (exclusive) {
+       if (get_type == EXCLUSIVE_GET) {
                rdev->exclusive = 1;
 
                ret = _regulator_is_enabled(rdev);
@@ -1710,7 +1717,7 @@ found:
  */
 struct regulator *regulator_get(struct device *dev, const char *id)
 {
-       return _regulator_get(dev, id, false, true);
+       return _regulator_get(dev, id, NORMAL_GET);
 }
 EXPORT_SYMBOL_GPL(regulator_get);
 
@@ -1737,7 +1744,7 @@ EXPORT_SYMBOL_GPL(regulator_get);
  */
 struct regulator *regulator_get_exclusive(struct device *dev, const char *id)
 {
-       return _regulator_get(dev, id, true, false);
+       return _regulator_get(dev, id, EXCLUSIVE_GET);
 }
 EXPORT_SYMBOL_GPL(regulator_get_exclusive);
 
@@ -1763,7 +1770,7 @@ EXPORT_SYMBOL_GPL(regulator_get_exclusive);
  */
 struct regulator *regulator_get_optional(struct device *dev, const char *id)
 {
-       return _regulator_get(dev, id, false, false);
+       return _regulator_get(dev, id, OPTIONAL_GET);
 }
 EXPORT_SYMBOL_GPL(regulator_get_optional);
 
@@ -3673,7 +3680,7 @@ err:
        for (++i; i < num_consumers; ++i) {
                r = regulator_enable(consumers[i].consumer);
                if (r != 0)
-                       pr_err("Failed to reename %s: %d\n",
+                       pr_err("Failed to re-enable %s: %d\n",
                               consumers[i].supply, r);
        }
 
@@ -3699,21 +3706,17 @@ int regulator_bulk_force_disable(int num_consumers,
                           struct regulator_bulk_data *consumers)
 {
        int i;
-       int ret;
+       int ret = 0;
 
-       for (i = 0; i < num_consumers; i++)
+       for (i = 0; i < num_consumers; i++) {
                consumers[i].ret =
                            regulator_force_disable(consumers[i].consumer);
 
-       for (i = 0; i < num_consumers; i++) {
-               if (consumers[i].ret != 0) {
+               /* Store first error for reporting */
+               if (consumers[i].ret && !ret)
                        ret = consumers[i].ret;
-                       goto out;
-               }
        }
 
-       return 0;
-out:
        return ret;
 }
 EXPORT_SYMBOL_GPL(regulator_bulk_force_disable);
@@ -4404,12 +4407,13 @@ static void regulator_summary_show_subtree(struct seq_file *s,
        seq_puts(s, "\n");
 
        list_for_each_entry(consumer, &rdev->consumer_list, list) {
-               if (consumer->dev->class == &regulator_class)
+               if (consumer->dev && consumer->dev->class == &regulator_class)
                        continue;
 
                seq_printf(s, "%*s%-*s ",
                           (level + 1) * 3 + 1, "",
-                          30 - (level + 1) * 3, dev_name(consumer->dev));
+                          30 - (level + 1) * 3,
+                          consumer->dev ? dev_name(consumer->dev) : "deviceless");
 
                switch (rdev->desc->type) {
                case REGULATOR_VOLTAGE:
@@ -4553,6 +4557,16 @@ static int __init regulator_init_complete(void)
        if (of_have_populated_dt())
                has_full_constraints = true;
 
+       /*
+        * Regulators may had failed to resolve their input supplies
+        * when were registered, either because the input supply was
+        * not registered yet or because its parent device was not
+        * bound yet. So attempt to resolve the input supplies for
+        * pending regulators before trying to disable unused ones.
+        */
+       class_for_each_device(&regulator_class, NULL, NULL,
+                             regulator_register_resolve_supply);
+
        /* If we have a full configuration then disable any regulators
         * we have permission to change the status for and which are
         * not in use or always_on.  This is effectively the default