regulator: Support voltage offsets to compensate for drops in system

[mv-sheeva.git] / drivers / regulator / core.c

diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
index 0fae51c4845a3cf703f220c11d313be6a8ee099c..58452ac0f165fa0b54025252d34eb8c206e68719 100644 (file)
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -197,9 +197,9 @@ static int regulator_check_current_limit(struct regulator_dev *rdev,
 }
 
 /* operating mode constraint check */
-static int regulator_check_mode(struct regulator_dev *rdev, int mode)
+static int regulator_mode_constrain(struct regulator_dev *rdev, int *mode)
 {
-       switch (mode) {
+       switch (*mode) {
        case REGULATOR_MODE_FAST:
        case REGULATOR_MODE_NORMAL:
        case REGULATOR_MODE_IDLE:
@@ -217,11 +217,17 @@ static int regulator_check_mode(struct regulator_dev *rdev, int mode)
                rdev_err(rdev, "operation not allowed\n");
                return -EPERM;
        }
-       if (!(rdev->constraints->valid_modes_mask & mode)) {
-               rdev_err(rdev, "invalid mode %x\n", mode);
-               return -EINVAL;
+
+       /* The modes are bitmasks, the most power hungry modes having
+        * the lowest values. If the requested mode isn't supported
+        * try higher modes. */
+       while (*mode) {
+               if (rdev->constraints->valid_modes_mask & *mode)
+                       return 0;
+               *mode /= 2;
        }
-       return 0;
+
+       return -EINVAL;
 }
 
 /* dynamic regulator mode switching constraint check */
@@ -612,7 +618,7 @@ static void drms_uA_update(struct regulator_dev *rdev)
                                                  output_uV, current_uA);
 
        /* check the new mode is allowed */
-       err = regulator_check_mode(rdev, mode);
+       err = regulator_mode_constrain(rdev, &mode);
        if (err == 0)
                rdev->desc->ops->set_mode(rdev, mode);
 }
@@ -718,6 +724,10 @@ static void print_constraints(struct regulator_dev *rdev)
                        count += sprintf(buf + count, "at %d mV ", ret / 1000);
        }
 
+       if (constraints->uV_offset)
+               count += sprintf(buf, "%dmV offset ",
+                                constraints->uV_offset / 1000);
+
        if (constraints->min_uA && constraints->max_uA) {
                if (constraints->min_uA == constraints->max_uA)
                        count += sprintf(buf + count, "%d mA ",
@@ -1498,13 +1508,14 @@ static int _regulator_force_disable(struct regulator_dev *rdev,
  */
 int regulator_force_disable(struct regulator *regulator)
 {
+       struct regulator_dev *rdev = regulator->rdev;
        struct regulator_dev *supply_rdev = NULL;
        int ret;
 
-       mutex_lock(&regulator->rdev->mutex);
+       mutex_lock(&rdev->mutex);
        regulator->uA_load = 0;
-       ret = _regulator_force_disable(regulator->rdev, &supply_rdev);
-       mutex_unlock(&regulator->rdev->mutex);
+       ret = _regulator_force_disable(rdev, &supply_rdev);
+       mutex_unlock(&rdev->mutex);
 
        if (supply_rdev)
                regulator_disable(get_device_regulator(rdev_get_dev(supply_rdev)));
@@ -1634,6 +1645,9 @@ static int _regulator_do_set_voltage(struct regulator_dev *rdev,
 
        trace_regulator_set_voltage(rdev_get_name(rdev), min_uV, max_uV);
 
+       min_uV += rdev->constraints->uV_offset;
+       max_uV += rdev->constraints->uV_offset;
+
        if (rdev->desc->ops->set_voltage) {
                ret = rdev->desc->ops->set_voltage(rdev, min_uV, max_uV,
                                                   &selector);
@@ -1858,18 +1872,20 @@ EXPORT_SYMBOL_GPL(regulator_sync_voltage);
 
 static int _regulator_get_voltage(struct regulator_dev *rdev)
 {
-       int sel;
+       int sel, ret;
 
        if (rdev->desc->ops->get_voltage_sel) {
                sel = rdev->desc->ops->get_voltage_sel(rdev);
                if (sel < 0)
                        return sel;
-               return rdev->desc->ops->list_voltage(rdev, sel);
+               ret = rdev->desc->ops->list_voltage(rdev, sel);
        }
        if (rdev->desc->ops->get_voltage)
-               return rdev->desc->ops->get_voltage(rdev);
+               ret = rdev->desc->ops->get_voltage(rdev);
        else
                return -EINVAL;
+
+       return ret - rdev->constraints->uV_offset;
 }
 
 /**
@@ -2005,7 +2021,7 @@ int regulator_set_mode(struct regulator *regulator, unsigned int mode)
        }
 
        /* constraints check */
-       ret = regulator_check_mode(rdev, mode);
+       ret = regulator_mode_constrain(rdev, &mode);
        if (ret < 0)
                goto out;
 
@@ -2116,7 +2132,7 @@ int regulator_set_optimum_mode(struct regulator *regulator, int uA_load)
        mode = rdev->desc->ops->get_optimum_mode(rdev,
                                                 input_uV, output_uV,
                                                 total_uA_load);
-       ret = regulator_check_mode(rdev, mode);
+       ret = regulator_mode_constrain(rdev, &mode);
        if (ret < 0) {
                rdev_err(rdev, "failed to get optimum mode @ %d uA %d -> %d uV\n",
                         total_uA_load, input_uV, output_uV);
@@ -2589,14 +2605,6 @@ struct regulator_dev *regulator_register(struct regulator_desc *regulator_desc,
        if (ret < 0)
                goto scrub;
 
-       /* set supply regulator if it exists */
-       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;
-       }
-
        if (init_data->supply_regulator) {
                struct regulator_dev *r;
                int found = 0;
@@ -2621,14 +2629,6 @@ struct regulator_dev *regulator_register(struct regulator_desc *regulator_desc,
                        goto scrub;
        }
 
-       if (init_data->supply_regulator_dev) {
-               dev_warn(dev, "Uses supply_regulator_dev instead of regulator_supply\n");
-               ret = set_supply(rdev,
-                       dev_get_drvdata(init_data->supply_regulator_dev));
-               if (ret < 0)
-                       goto scrub;
-       }
-
        /* add consumers devices */
        for (i = 0; i < init_data->num_consumer_supplies; i++) {
                ret = set_consumer_device_supply(rdev,