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>

drivers/regulator/wm8350-regulator.c

@@ -360,7 +360,7 @@ int wm8350_isink_set_flash(struct wm8350 *wm8350, int isink, u16 mode,
 EXPORT_SYMBOL_GPL(wm8350_isink_set_flash);
 
 static int wm8350_dcdc_set_voltage(struct regulator_dev *rdev, int min_uV,
-	int max_uV)
+				   int max_uV, unsigned *selector)
 {
 	struct wm8350 *wm8350 = rdev_get_drvdata(rdev);
 	int volt_reg, dcdc = rdev_get_id(rdev), mV,
@@ -397,6 +397,8 @@ static int wm8350_dcdc_set_voltage(struct regulator_dev *rdev, int min_uV,
 		return -EINVAL;
 	}
 
+	*selector = mV;
+
 	/* all DCDCs have same mV bits */
 	val = wm8350_reg_read(wm8350, volt_reg) & ~WM8350_DC1_VSEL_MASK;
 	wm8350_reg_write(wm8350, volt_reg, val | mV);
@@ -754,7 +756,7 @@ static int wm8350_ldo_set_suspend_disable(struct regulator_dev *rdev)
 }
 
 static int wm8350_ldo_set_voltage(struct regulator_dev *rdev, int min_uV,
-	int max_uV)
+				  int max_uV, unsigned *selector)
 {
 	struct wm8350 *wm8350 = rdev_get_drvdata(rdev);
 	int volt_reg, ldo = rdev_get_id(rdev), mV, min_mV = min_uV / 1000,
@@ -797,6 +799,8 @@ static int wm8350_ldo_set_voltage(struct regulator_dev *rdev, int min_uV,
 		return -EINVAL;
 	}
 
+	*selector = mV;
+
 	/* all LDOs have same mV bits */
 	val = wm8350_reg_read(wm8350, volt_reg) & ~WM8350_LDO1_VSEL_MASK;
 	wm8350_reg_write(wm8350, volt_reg, val | mV);