regulator: Allow drivers to report voltages as selectors

Since drivers already have to provide an API for translating selectors
into voltages they may as well just report the selector values directly
to the core API rather than implement the lookup themselves. The old
interface is left in place for now, but may be removed in future.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>

1 files changed, 22 insertions, 3 deletions

diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
index 671eb53b5cdc..b362dbde80f7 100644
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -577,7 +577,9 @@ static void drms_uA_update(struct regulator_dev *rdev)
 
         err = regulator_check_drms(rdev);
         if (err < 0 || !rdev->desc->ops->get_optimum_mode ||
-            !rdev->desc->ops->get_voltage || !rdev->desc->ops->set_mode)
+            (!rdev->desc->ops->get_voltage &&
+             !rdev->desc->ops->get_voltage_sel) ||
+            !rdev->desc->ops->set_mode)
                 return;
 
         /* get output voltage */
@@ -1682,7 +1684,14 @@ EXPORT_SYMBOL_GPL(regulator_set_voltage);
 
 static int _regulator_get_voltage(struct regulator_dev *rdev)
 {
-        /* sanity check */
+        int sel;
+
+        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);
+        }
         if (rdev->desc->ops->get_voltage)
                 return rdev->desc->ops->get_voltage(rdev);
         else
@@ -2191,7 +2200,7 @@ static int add_regulator_attributes(struct regulator_dev *rdev)
         int                     status = 0;
 
         /* some attributes need specific methods to be displayed */
-        if (ops->get_voltage) {
+        if (ops->get_voltage || ops->get_voltage_sel) {
                 status = device_create_file(dev, &dev_attr_microvolts);
                 if (status < 0)
                         return status;
@@ -2327,6 +2336,16 @@ struct regulator_dev *regulator_register(struct regulator_desc *regulator_desc,
         if (!init_data)
                 return ERR_PTR(-EINVAL);
 
+        /* Only one of each should be implemented */
+        WARN_ON(regulator_desc->ops->get_voltage &&
+                regulator_desc->ops->get_voltage_sel);
+
+        /* If we're using selectors we must implement list_voltage. */
+        if (regulator_desc->ops->get_voltage_sel &&
+            !regulator_desc->ops->list_voltage) {
+                return ERR_PTR(-EINVAL);
+        }
+
         rdev = kzalloc(sizeof(struct regulator_dev), GFP_KERNEL);
         if (rdev == NULL)
                 return ERR_PTR(-ENOMEM);