regulator: Report actual configured voltage to set_voltage()

Change the interface used by set_voltage() to report the selected value
to the regulator core in terms of a selector used by list_voltage().
This allows the regulator core to know the voltage that was chosen
without having to do an explict get_voltage(), which would be much more
expensive as it will generally access hardware.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
diff --git a/drivers/regulator/lp3972.c b/drivers/regulator/lp3972.c
index e07062f..6aa1b50 100644
--- a/drivers/regulator/lp3972.c
+++ b/drivers/regulator/lp3972.c
@@ -292,7 +292,8 @@
 }
 
 static int lp3972_ldo_set_voltage(struct regulator_dev *dev,
-				  int min_uV, int max_uV)
+				  int min_uV, int max_uV,
+				  unsigned int *selector)
 {
 	struct lp3972 *lp3972 = rdev_get_drvdata(dev);
 	int ldo = rdev_get_id(dev) - LP3972_LDO1;
@@ -313,6 +314,8 @@
 	if (val > LP3972_LDO_VOL_MAX_IDX(ldo) || vol_map[val] > max_vol)
 		return -EINVAL;
 
+	*selector = val;
+
 	shift = LP3972_LDO_VOL_CONTR_SHIFT(ldo);
 	ret = lp3972_set_bits(lp3972, LP3972_LDO_VOL_CONTR_REG(ldo),
 		LP3972_LDO_VOL_MASK(ldo) << shift, val << shift);
@@ -416,7 +419,8 @@
 }
 
 static int lp3972_dcdc_set_voltage(struct regulator_dev *dev,
-				  int min_uV, int max_uV)
+				   int min_uV, int max_uV,
+				   unsigned int *selector)
 {
 	struct lp3972 *lp3972 = rdev_get_drvdata(dev);
 	int buck = rdev_get_id(dev) - LP3972_DCDC1;
@@ -438,6 +442,8 @@
 	    vol_map[val] > max_vol)
 		return -EINVAL;
 
+	*selector = val;
+
 	ret = lp3972_set_bits(lp3972, LP3972_BUCK_VOL1_REG(buck),
 				LP3972_BUCK_VOL_MASK, val);
 	if (ret)