regulator: core: Check that the selector from map_voltage() is valid

Lots of regulator drivers have checks in their map_voltage() functions
to verify that the result of the mapping is in the range originally
specified. Factor these out in the core and provide a bit of extra
defensiveness for other drivers by doing the check in the core.

Since we're now doing a list_voltage() earlier move the current mapping
back to a voltage out into the set_voltage() call to save redoing it.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
index a808866262304fbcffde01262d549b50520dc4ea..f98a8ee299337fc8f58c9b9408565b3baee90466 100644 (file)
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -2040,7 +2040,7 @@ static int _regulator_do_set_voltage(struct regulator_dev *rdev,
 {
        int ret;
        int delay = 0;
-       int best_val;
+       int best_val = 0;
        unsigned int selector;
        int old_selector = -1;
 
@@ -2064,6 +2064,15 @@ static int _regulator_do_set_voltage(struct regulator_dev *rdev,
        if (rdev->desc->ops->set_voltage) {
                ret = rdev->desc->ops->set_voltage(rdev, min_uV, max_uV,
                                                   &selector);
+
+               if (ret >= 0) {
+                       if (rdev->desc->ops->list_voltage)
+                               best_val = rdev->desc->ops->list_voltage(rdev,
+                                                                        selector);
+                       else
+                               best_val = _regulator_get_voltage(rdev);
+               }
+
        } else if (rdev->desc->ops->set_voltage_sel) {
                if (rdev->desc->ops->map_voltage) {
                        ret = rdev->desc->ops->map_voltage(rdev, min_uV,
@@ -2079,18 +2088,19 @@ static int _regulator_do_set_voltage(struct regulator_dev *rdev,
                }
 
                if (ret >= 0) {
-                       selector = ret;
-                       ret = rdev->desc->ops->set_voltage_sel(rdev, ret);
+                       best_val = rdev->desc->ops->list_voltage(rdev, ret);
+                       if (min_uV <= best_val && max_uV >= best_val) {
+                               selector = ret;
+                               ret = rdev->desc->ops->set_voltage_sel(rdev,
+                                                                      ret);
+                       } else {
+                               ret = -EINVAL;
+                       }
                }
        } else {
                ret = -EINVAL;
        }
 
-       if (rdev->desc->ops->list_voltage)
-               best_val = rdev->desc->ops->list_voltage(rdev, selector);
-       else
-               best_val = _regulator_get_voltage(rdev);
-
        /* Call set_voltage_time_sel if successfully obtained old_selector */
        if (ret == 0 && _regulator_is_enabled(rdev) && old_selector >= 0 &&
            rdev->desc->ops->set_voltage_time_sel) {