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/wm8400-regulator.c b/drivers/regulator/wm8400-regulator.c
index 924c7eb..b42d01c 100644
--- a/drivers/regulator/wm8400-regulator.c
+++ b/drivers/regulator/wm8400-regulator.c
@@ -67,7 +67,7 @@
 }
 
 static int wm8400_ldo_set_voltage(struct regulator_dev *dev,
-				  int min_uV, int max_uV)
+				  int min_uV, int max_uV, unsigned *selector)
 {
 	struct wm8400 *wm8400 = rdev_get_drvdata(dev);
 	u16 val;
@@ -93,6 +93,8 @@
 		val += 0xf;
 	}
 
+	*selector = val;
+
 	return wm8400_set_bits(wm8400, WM8400_LDO1_CONTROL + rdev_get_id(dev),
 			       WM8400_LDO1_VSEL_MASK, val);
 }
@@ -156,7 +158,7 @@
 }
 
 static int wm8400_dcdc_set_voltage(struct regulator_dev *dev,
-				  int min_uV, int max_uV)
+				   int min_uV, int max_uV, unsigned *selector)
 {
 	struct wm8400 *wm8400 = rdev_get_drvdata(dev);
 	u16 val;
@@ -171,6 +173,8 @@
 		return -EINVAL;
 	BUG_ON(850000 + (25000 * val) < min_uV);
 
+	*selector = val;
+
 	return wm8400_set_bits(wm8400, WM8400_DCDC1_CONTROL_1 + offset,
 			       WM8400_DC1_VSEL_MASK, val);
 }