1 files changed, 99 insertions, 0 deletions
diff --git a/drivers/regulator/helpers.c b/drivers/regulator/helpers.c
index 4495b4403f..f22d21b35d 100644
--- a/drivers/regulator/helpers.c
+++ b/drivers/regulator/helpers.c
@@ -85,3 +85,102 @@ int regulator_disable_regmap(struct regulator_dev *rdev)
 				  rdev->desc->enable_mask, val);
 }
 EXPORT_SYMBOL_GPL(regulator_disable_regmap);
+
+/**
+ * regulator_set_voltage_sel_regmap - standard set_voltage_sel for regmap users
+ *
+ * @rdev: regulator to operate on
+ * @sel: Selector to set
+ *
+ * Regulators that use regmap for their register I/O can set the
+ * vsel_reg and vsel_mask fields in their descriptor and then use this
+ * as their set_voltage_vsel operation, saving some code.
+ */
+int regulator_set_voltage_sel_regmap(struct regulator_dev *rdev, unsigned sel)
+{
+	int ret;
+
+	sel <<= ffs(rdev->desc->vsel_mask) - 1;
+
+	ret = regmap_update_bits(rdev->regmap, rdev->desc->vsel_reg,
+				  rdev->desc->vsel_mask, sel);
+	if (ret)
+		return ret;
+
+	if (rdev->desc->apply_bit)
+		ret = regmap_update_bits(rdev->regmap, rdev->desc->apply_reg,
+					 rdev->desc->apply_bit,
+					 rdev->desc->apply_bit);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(regulator_set_voltage_sel_regmap);
+
+/**
+ * regulator_map_voltage_linear - map_voltage() for simple linear mappings
+ *
+ * @rdev: Regulator to operate on
+ * @min_uV: Lower bound for voltage
+ * @max_uV: Upper bound for voltage
+ *
+ * Drivers providing min_uV and uV_step in their regulator_desc can
+ * use this as their map_voltage() operation.
+ */
+int regulator_map_voltage_linear(struct regulator_dev *rdev,
+				 int min_uV, int max_uV)
+{
+	int ret, voltage;
+
+	/* Allow uV_step to be 0 for fixed voltage */
+	if (rdev->desc->n_voltages == 1 && rdev->desc->uV_step == 0) {
+		if (min_uV <= rdev->desc->min_uV && rdev->desc->min_uV <= max_uV)
+			return 0;
+		else
+			return -EINVAL;
+	}
+
+	if (!rdev->desc->uV_step) {
+		BUG_ON(!rdev->desc->uV_step);
+		return -EINVAL;
+	}
+
+	if (min_uV < rdev->desc->min_uV)
+		min_uV = rdev->desc->min_uV;
+
+	ret = DIV_ROUND_UP(min_uV - rdev->desc->min_uV, rdev->desc->uV_step);
+	if (ret < 0)
+		return ret;
+
+	ret += rdev->desc->linear_min_sel;
+
+	/* Map back into a voltage to verify we're still in bounds */
+	voltage = rdev->desc->ops->list_voltage(rdev, ret);
+	if (voltage < min_uV || voltage > max_uV)
+		return -EINVAL;
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(regulator_map_voltage_linear);
+
+/**
+ * regulator_list_voltage_linear - List voltages with simple calculation
+ *
+ * @rdev: Regulator device
+ * @selector: Selector to convert into a voltage
+ *
+ * Regulators with a simple linear mapping between voltages and
+ * selectors can set min_uV and uV_step in the regulator descriptor
+ * and then use this function as their list_voltage() operation,
+ */
+int regulator_list_voltage_linear(struct regulator_dev *rdev,
+				  unsigned int selector)
+{
+	if (selector >= rdev->desc->n_voltages)
+		return -EINVAL;
+	if (selector < rdev->desc->linear_min_sel)
+		return 0;
+
+	selector -= rdev->desc->linear_min_sel;
+
+	return rdev->desc->min_uV + (rdev->desc->uV_step * selector);
+}
+EXPORT_SYMBOL_GPL(regulator_list_voltage_linear);