regulator: Revert coupled regulator support again
[sfrench/cifs-2.6.git] / drivers / regulator / core.c
index ac97e21bff100071855bd1770ee35bf49cded03d..6ed568b96c0ec1edf77cc2b4059c36d51b58cb93 100644 (file)
@@ -105,11 +105,6 @@ static int _notifier_call_chain(struct regulator_dev *rdev,
                                  unsigned long event, void *data);
 static int _regulator_do_set_voltage(struct regulator_dev *rdev,
                                     int min_uV, int max_uV);
-static int regulator_balance_voltage(struct regulator_dev *rdev,
-                                    suspend_state_t state);
-static int regulator_set_voltage_rdev(struct regulator_dev *rdev,
-                                     int min_uV, int max_uV,
-                                     suspend_state_t state);
 static struct regulator *create_regulator(struct regulator_dev *rdev,
                                          struct device *dev,
                                          const char *supply_name);
@@ -201,66 +196,37 @@ static void regulator_unlock(struct regulator_dev *rdev)
        }
 }
 
-static int regulator_lock_recursive(struct regulator_dev *rdev,
-                                   unsigned int subclass)
+/**
+ * regulator_lock_supply - lock a regulator and its supplies
+ * @rdev:         regulator source
+ */
+static void regulator_lock_supply(struct regulator_dev *rdev)
 {
-       struct regulator_dev *c_rdev;
        int i;
 
-       for (i = 0; i < rdev->coupling_desc.n_coupled; i++) {
-               c_rdev = rdev->coupling_desc.coupled_rdevs[i];
-
-               if (!c_rdev)
-                       continue;
-
-               regulator_lock_nested(c_rdev, subclass++);
-
-               if (c_rdev->supply)
-                       subclass =
-                               regulator_lock_recursive(c_rdev->supply->rdev,
-                                                        subclass);
-       }
-
-       return subclass;
+       for (i = 0; rdev; rdev = rdev_get_supply(rdev), i++)
+               regulator_lock_nested(rdev, i);
 }
 
 /**
- * regulator_unlock_dependent - unlock regulator's suppliers and coupled
- *                             regulators
- * @rdev:                      regulator source
- *
- * Unlock all regulators related with rdev by coupling or suppling.
+ * regulator_unlock_supply - unlock a regulator and its supplies
+ * @rdev:         regulator source
  */
-static void regulator_unlock_dependent(struct regulator_dev *rdev)
+static void regulator_unlock_supply(struct regulator_dev *rdev)
 {
-       struct regulator_dev *c_rdev;
-       int i;
+       struct regulator *supply;
 
-       for (i = 0; i < rdev->coupling_desc.n_coupled; i++) {
-               c_rdev = rdev->coupling_desc.coupled_rdevs[i];
-
-               if (!c_rdev)
-                       continue;
+       while (1) {
+               regulator_unlock(rdev);
+               supply = rdev->supply;
 
-               regulator_unlock(c_rdev);
+               if (!rdev->supply)
+                       return;
 
-               if (c_rdev->supply)
-                       regulator_unlock_dependent(c_rdev->supply->rdev);
+               rdev = supply->rdev;
        }
 }
 
-/**
- * regulator_lock_dependent - lock regulator's suppliers and coupled regulators
- * @rdev:                      regulator source
- *
- * This function as a wrapper on regulator_lock_recursive(), which locks
- * all regulators related with rdev by coupling or suppling.
- */
-static inline void regulator_lock_dependent(struct regulator_dev *rdev)
-{
-       regulator_lock_recursive(rdev, 0);
-}
-
 /**
  * of_get_regulator - get a regulator device node based on supply name
  * @dev: Device pointer for the consumer (of regulator) device
@@ -2293,11 +2259,6 @@ int regulator_enable(struct regulator *regulator)
        struct regulator_dev *rdev = regulator->rdev;
        int ret = 0;
 
-       if (rdev->coupling_desc.n_resolved != rdev->coupling_desc.n_coupled) {
-               rdev_err(rdev, "not all coupled regulators registered\n");
-               return -EPERM;
-       }
-
        if (regulator->always_on)
                return 0;
 
@@ -2307,12 +2268,9 @@ int regulator_enable(struct regulator *regulator)
                        return ret;
        }
 
-       regulator_lock_dependent(rdev);
+       mutex_lock(&rdev->mutex);
        ret = _regulator_enable(rdev);
-       /* balance only if there are regulators coupled */
-       if (rdev->coupling_desc.n_coupled > 1)
-               regulator_balance_voltage(rdev, PM_SUSPEND_ON);
-       regulator_unlock_dependent(rdev);
+       mutex_unlock(&rdev->mutex);
 
        if (ret != 0 && rdev->supply)
                regulator_disable(rdev->supply);
@@ -2418,11 +2376,9 @@ int regulator_disable(struct regulator *regulator)
        if (regulator->always_on)
                return 0;
 
-       regulator_lock_dependent(rdev);
+       mutex_lock(&rdev->mutex);
        ret = _regulator_disable(rdev);
-       if (rdev->coupling_desc.n_coupled > 1)
-               regulator_balance_voltage(rdev, PM_SUSPEND_ON);
-       regulator_unlock_dependent(rdev);
+       mutex_unlock(&rdev->mutex);
 
        if (ret == 0 && rdev->supply)
                regulator_disable(rdev->supply);
@@ -2471,12 +2427,10 @@ int regulator_force_disable(struct regulator *regulator)
        struct regulator_dev *rdev = regulator->rdev;
        int ret;
 
-       regulator_lock_dependent(rdev);
+       mutex_lock(&rdev->mutex);
        regulator->uA_load = 0;
        ret = _regulator_force_disable(regulator->rdev);
-       if (rdev->coupling_desc.n_coupled > 1)
-               regulator_balance_voltage(rdev, PM_SUSPEND_ON);
-       regulator_unlock_dependent(rdev);
+       mutex_unlock(&rdev->mutex);
 
        if (rdev->supply)
                while (rdev->open_count--)
@@ -2624,9 +2578,9 @@ int regulator_is_enabled(struct regulator *regulator)
        if (regulator->always_on)
                return 1;
 
-       regulator_lock_dependent(regulator->rdev);
+       mutex_lock(&regulator->rdev->mutex);
        ret = _regulator_is_enabled(regulator->rdev);
-       regulator_unlock_dependent(regulator->rdev);
+       mutex_unlock(&regulator->rdev->mutex);
 
        return ret;
 }
@@ -3035,12 +2989,8 @@ static int regulator_set_voltage_unlocked(struct regulator *regulator,
        int ret = 0;
        int old_min_uV, old_max_uV;
        int current_uV;
-
-       if (rdev->coupling_desc.n_resolved != rdev->coupling_desc.n_coupled) {
-               rdev_err(rdev, "not all coupled regulators registered\n");
-               ret = -EPERM;
-               goto out;
-       }
+       int best_supply_uV = 0;
+       int supply_change_uV = 0;
 
        /* If we're setting the same range as last time the change
         * should be a noop (some cpufreq implementations use the same
@@ -3084,27 +3034,6 @@ static int regulator_set_voltage_unlocked(struct regulator *regulator,
        if (ret < 0)
                goto out2;
 
-       /* for not coupled regulators this will just set the voltage */
-       ret = regulator_balance_voltage(rdev, state);
-       if (ret < 0)
-               goto out2;
-
-out:
-       return 0;
-out2:
-       voltage->min_uV = old_min_uV;
-       voltage->max_uV = old_max_uV;
-
-       return ret;
-}
-
-static int regulator_set_voltage_rdev(struct regulator_dev *rdev, int min_uV,
-                                     int max_uV, suspend_state_t state)
-{
-       int best_supply_uV = 0;
-       int supply_change_uV = 0;
-       int ret;
-
        if (rdev->supply &&
            regulator_ops_is_valid(rdev->supply->rdev,
                                   REGULATOR_CHANGE_VOLTAGE) &&
@@ -3116,13 +3045,13 @@ static int regulator_set_voltage_rdev(struct regulator_dev *rdev, int min_uV,
                selector = regulator_map_voltage(rdev, min_uV, max_uV);
                if (selector < 0) {
                        ret = selector;
-                       goto out;
+                       goto out2;
                }
 
                best_supply_uV = _regulator_list_voltage(rdev, selector, 0);
                if (best_supply_uV < 0) {
                        ret = best_supply_uV;
-                       goto out;
+                       goto out2;
                }
 
                best_supply_uV += rdev->desc->min_dropout_uV;
@@ -3130,7 +3059,7 @@ static int regulator_set_voltage_rdev(struct regulator_dev *rdev, int min_uV,
                current_supply_uV = _regulator_get_voltage(rdev->supply->rdev);
                if (current_supply_uV < 0) {
                        ret = current_supply_uV;
-                       goto out;
+                       goto out2;
                }
 
                supply_change_uV = best_supply_uV - current_supply_uV;
@@ -3142,7 +3071,7 @@ static int regulator_set_voltage_rdev(struct regulator_dev *rdev, int min_uV,
                if (ret) {
                        dev_err(&rdev->dev, "Failed to increase supply voltage: %d\n",
                                        ret);
-                       goto out;
+                       goto out2;
                }
        }
 
@@ -3152,7 +3081,7 @@ static int regulator_set_voltage_rdev(struct regulator_dev *rdev, int min_uV,
                ret = _regulator_do_set_suspend_voltage(rdev, min_uV,
                                                        max_uV, state);
        if (ret < 0)
-               goto out;
+               goto out2;
 
        if (supply_change_uV < 0) {
                ret = regulator_set_voltage_unlocked(rdev->supply,
@@ -3166,186 +3095,10 @@ static int regulator_set_voltage_rdev(struct regulator_dev *rdev, int min_uV,
 
 out:
        return ret;
-}
-
-static int regulator_get_optimal_voltage(struct regulator_dev *rdev)
-{
-       struct coupling_desc *c_desc = &rdev->coupling_desc;
-       struct regulator_dev **c_rdevs = c_desc->coupled_rdevs;
-       int max_spread = rdev->constraints->max_spread;
-       int n_coupled = c_desc->n_coupled;
-       int desired_min_uV, desired_max_uV, min_current_uV = INT_MAX;
-       int max_current_uV = 0, highest_min_uV = 0, target_uV, possible_uV;
-       int i, ret;
-
-       /* If consumers don't provide any demands, set voltage to min_uV */
-       desired_min_uV = rdev->constraints->min_uV;
-       desired_max_uV = rdev->constraints->max_uV;
-       ret = regulator_check_consumers(rdev,
-                                       &desired_min_uV,
-                                       &desired_max_uV, PM_SUSPEND_ON);
-       if (ret < 0)
-               goto out;
-
-       /*
-        * If there are no coupled regulators, simply set the voltage demanded
-        * by consumers.
-        */
-       if (n_coupled == 1) {
-               ret = desired_min_uV;
-               goto out;
-       }
-
-       /* Find highest min desired voltage */
-       for (i = 0; i < n_coupled; i++) {
-               int tmp_min = 0;
-               int tmp_max = INT_MAX;
-
-               if (!_regulator_is_enabled(c_rdevs[i]))
-                       continue;
-
-               ret = regulator_check_consumers(c_rdevs[i],
-                                               &tmp_min,
-                                               &tmp_max, PM_SUSPEND_ON);
-               if (ret < 0)
-                       goto out;
-
-               if (tmp_min > highest_min_uV)
-                       highest_min_uV = tmp_min;
-       }
-
-       /*
-        * Let target_uV be equal to the desired one if possible.
-        * If not, set it to minimum voltage, allowed by other coupled
-        * regulators.
-        */
-       target_uV = max(desired_min_uV,  highest_min_uV - max_spread);
-
-       /*
-        * Find min and max voltages, which currently aren't
-        * violating max_spread
-        */
-       for (i = 0; i < n_coupled; i++) {
-               int tmp_act;
-
-               /*
-                * Don't check the regulator, which is about
-                * to change voltage
-                */
-               if (c_rdevs[i] == rdev)
-                       continue;
-               if (!_regulator_is_enabled(c_rdevs[i]))
-                       continue;
-
-               tmp_act = _regulator_get_voltage(c_rdevs[i]);
-               if (tmp_act < 0) {
-                       ret = tmp_act;
-                       goto out;
-               }
-
-               if (tmp_act < min_current_uV)
-                       min_current_uV = tmp_act;
-
-               if (tmp_act > max_current_uV)
-                       max_current_uV = tmp_act;
-       }
-
-       /* There aren't any other regulators enabled */
-       if (max_current_uV == 0) {
-               possible_uV = target_uV;
-       } else {
-               /*
-                * Correct target voltage, so as it currently isn't
-                * violating max_spread
-                */
-               possible_uV = max(target_uV, max_current_uV - max_spread);
-               possible_uV = min(possible_uV, min_current_uV + max_spread);
-       }
-
-       if (possible_uV > desired_max_uV) {
-               ret = -EINVAL;
-               goto out;
-       }
-       ret = possible_uV;
-
-out:
-       return ret;
-}
-
-static int regulator_balance_voltage(struct regulator_dev *rdev,
-                                    suspend_state_t state)
-{
-       struct regulator_dev **c_rdevs;
-       struct regulator_dev *best_rdev;
-       struct coupling_desc *c_desc = &rdev->coupling_desc;
-       int n_coupled;
-       int i, best_delta, best_uV, ret = 1;
-
-       c_rdevs = c_desc->coupled_rdevs;
-       n_coupled = c_desc->n_coupled;
-
-       /*
-        * if system is in a state other than PM_SUSPEND_ON, don't check
-        * other coupled regulators
-        */
-       if (state != PM_SUSPEND_ON)
-               n_coupled = 1;
-
-       /*
-        * Find the best possible voltage change on each loop. Leave the loop
-        * if there isn't any possible change.
-        */
-       while (1) {
-               best_delta = 0;
-               best_uV = 0;
-               best_rdev = NULL;
-
-               /*
-                * Find highest difference between optimal voltage
-                * and current voltage.
-                */
-               for (i = 0; i < n_coupled; i++) {
-                       /*
-                        * optimal_uV is the best voltage that can be set for
-                        * i-th regulator at the moment without violating
-                        * max_spread constraint in order to balance
-                        * the coupled voltages.
-                        */
-                       int optimal_uV, current_uV;
-
-                       optimal_uV = regulator_get_optimal_voltage(c_rdevs[i]);
-                       if (optimal_uV < 0) {
-                               ret = optimal_uV;
-                               goto out;
-                       }
-
-                       current_uV = _regulator_get_voltage(c_rdevs[i]);
-                       if (current_uV < 0) {
-                               ret = optimal_uV;
-                               goto out;
-                       }
-
-                       if (abs(best_delta) < abs(optimal_uV - current_uV)) {
-                               best_delta = optimal_uV - current_uV;
-                               best_rdev = c_rdevs[i];
-                               best_uV = optimal_uV;
-                       }
-               }
-
-               /* Nothing to change, return successfully */
-               if (!best_rdev) {
-                       ret = 0;
-                       goto out;
-               }
-
-               ret = regulator_set_voltage_rdev(best_rdev, best_uV,
-                                                best_uV, state);
-
-               if (ret < 0)
-                       goto out;
-       }
+out2:
+       voltage->min_uV = old_min_uV;
+       voltage->max_uV = old_max_uV;
 
-out:
        return ret;
 }
 
@@ -3371,12 +3124,12 @@ int regulator_set_voltage(struct regulator *regulator, int min_uV, int max_uV)
 {
        int ret = 0;
 
-       regulator_lock_dependent(regulator->rdev);
+       regulator_lock_supply(regulator->rdev);
 
        ret = regulator_set_voltage_unlocked(regulator, min_uV, max_uV,
                                             PM_SUSPEND_ON);
 
-       regulator_unlock_dependent(regulator->rdev);
+       regulator_unlock_supply(regulator->rdev);
 
        return ret;
 }
@@ -3454,12 +3207,12 @@ int regulator_set_suspend_voltage(struct regulator *regulator, int min_uV,
        if (regulator_check_states(state) || state == PM_SUSPEND_ON)
                return -EINVAL;
 
-       regulator_lock_dependent(regulator->rdev);
+       regulator_lock_supply(regulator->rdev);
 
        ret = _regulator_set_suspend_voltage(regulator, min_uV,
                                             max_uV, state);
 
-       regulator_unlock_dependent(regulator->rdev);
+       regulator_unlock_supply(regulator->rdev);
 
        return ret;
 }
@@ -3651,11 +3404,11 @@ int regulator_get_voltage(struct regulator *regulator)
 {
        int ret;
 
-       regulator_lock_dependent(regulator->rdev);
+       regulator_lock_supply(regulator->rdev);
 
        ret = _regulator_get_voltage(regulator->rdev);
 
-       regulator_unlock_dependent(regulator->rdev);
+       regulator_unlock_supply(regulator->rdev);
 
        return ret;
 }