regulator: core: Fix continuous_voltage_range case in regulator_can_change_voltage

Regulator drivers with continuous_voltage_range flag set allows not setting
n_voltages. Thus if continuous_voltage_range is set, check the constraint range
instead.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

drivers/regulator/core.c

@@ -1885,10 +1885,16 @@ int regulator_can_change_voltage(struct regulator *regulator)
 	struct regulator_dev	*rdev = regulator->rdev;
 
 	if (rdev->constraints &&
-	    rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE &&
-	    (rdev->desc->n_voltages - rdev->desc->linear_min_sel) > 1)
+	    (rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE)) {
+		if (rdev->desc->n_voltages - rdev->desc->linear_min_sel > 1)
 			return 1;
 
+		if (rdev->desc->continuous_voltage_range &&
+		    rdev->constraints->min_uV && rdev->constraints->max_uV &&
+		    rdev->constraints->min_uV != rdev->constraints->max_uV)
+			return 1;
+	}
+
 	return 0;
 }
 EXPORT_SYMBOL_GPL(regulator_can_change_voltage);