regulator: core: Allow drivers to set voltage mapping table in regulator_desc

Some regulator hardware use table based mapping can set volt_table in
regulator_desc and use regulator_list_voltage_table() for their list_voltage
callback.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Acked-by: Liam Girdwood <lrg@ti.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

1 files changed, 25 insertions, 0 deletions

diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
index 7584a74eec8a..333b7ebe7cae 100644
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -1883,6 +1883,31 @@ int regulator_list_voltage_linear(struct regulator_dev *rdev,
 EXPORT_SYMBOL_GPL(regulator_list_voltage_linear);
 
 /**
+ * regulator_list_voltage_table - List voltages with table based mapping
+ *
+ * @rdev: Regulator device
+ * @selector: Selector to convert into a voltage
+ *
+ * Regulators with table based mapping between voltages and
+ * selectors can set volt_table in the regulator descriptor
+ * and then use this function as their list_voltage() operation.
+ */
+int regulator_list_voltage_table(struct regulator_dev *rdev,
+                                 unsigned int selector)
+{
+        if (!rdev->desc->volt_table) {
+                BUG_ON(!rdev->desc->volt_table);
+                return -EINVAL;
+        }
+
+        if (selector >= rdev->desc->n_voltages)
+                return -EINVAL;
+
+        return rdev->desc->volt_table[selector];
+}
+EXPORT_SYMBOL_GPL(regulator_list_voltage_table);
+
+/**
  * regulator_list_voltage - enumerate supported voltages
  * @regulator: regulator source
  * @selector: identify voltage to list