drivers: regulator: provide generic regulator_is_supported_voltage

The function can be implemented by using regulator_count_voltages() +
regulator_list_voltage(), so there's no need to defer the job to each
driver.

Signed-off-by: Gerard Marull-Paretas <gerard.marull@nordicsemi.no>

drivers/regulator/regulator_common.c

@@ -63,3 +63,21 @@ int regulator_disable(const struct device *dev)
 
 	return ret;
 }
+
+bool regulator_is_supported_voltage(const struct device *dev, int32_t min_uv,
+				    int32_t max_uv)
+{
+	unsigned int volt_cnt = regulator_count_voltages(dev);
+
+	for (unsigned int idx = 0U; idx < volt_cnt; idx++) {
+		int32_t volt_uv;
+
+		(void)regulator_list_voltage(dev, idx, &volt_uv);
+
+		if ((volt_uv > min_uv) && (volt_uv < max_uv)) {
+			return true;
+		}
+	}
+
+	return false;
+}

drivers/regulator/regulator_pca9420.c

@@ -188,10 +188,6 @@ static const struct regulator_pca9420_desc ldo2_desc = {
 	.num_ranges = ARRAY_SIZE(ldo2_ranges),
 };
 
-static int regulator_pca9420_is_supported_voltage(const struct device *dev,
-						  int32_t min_uv,
-						  int32_t max_uv);
-
 static bool regulator_pca9420_is_mode_allowed(const struct device *dev,
 					      uint8_t mode)
 {
@@ -281,22 +277,6 @@ static int regulator_pca9420_list_voltage(const struct device *dev,
 					    volt_uv);
 }
 
-/**
- * Part of the extended regulator consumer API
- * Returns true if the regulator supports a voltage in the given range.
- */
-static int regulator_pca9420_is_supported_voltage(const struct device *dev,
-						  int32_t min_uv,
-						  int32_t max_uv)
-{
-	const struct regulator_pca9420_config *config = dev->config;
-	uint16_t idx;
-
-	return linear_range_group_get_win_index(config->desc->ranges,
-						config->desc->num_ranges,
-						min_uv, max_uv, &idx);
-}
-
 /**
  * Part of the extended regulator consumer API
  * Sets the output voltage to the closest supported voltage value
@@ -528,7 +508,6 @@ static const struct regulator_driver_api api = {
 	.disable = regulator_pca9420_disable,
 	.count_voltages = regulator_pca9420_count_voltages,
 	.list_voltage = regulator_pca9420_list_voltage,
-	.is_supported_voltage = regulator_pca9420_is_supported_voltage,
 	.set_voltage = regulator_pca9420_set_voltage,
 	.get_voltage = regulator_pca9420_get_voltage,
 	.get_current_limit = regulator_pca9420_get_current_limit,

include/zephyr/drivers/regulator.h

@@ -34,8 +34,6 @@ __subsystem struct regulator_driver_api {
 	unsigned int (*count_voltages)(const struct device *dev);
 	int (*list_voltage)(const struct device *dev, unsigned int idx,
 			    int32_t *volt_uv);
-	int (*is_supported_voltage)(const struct device *dev, int32_t min_uv,
-				    int32_t max_uv);
 	int (*set_voltage)(const struct device *dev, int32_t min_uv,
 			   int32_t max_uv);
 	int32_t (*get_voltage)(const struct device *dev);
@@ -157,28 +155,17 @@ static inline int regulator_list_voltage(const struct device *dev,
 }
 
 /**
- * @brief Check if a voltage range is supported.
+ * @brief Check if a voltage within a window is supported.
  *
  * @param dev Regulator device instance.
  * @param min_uv Minimum voltage in microvolts.
  * @param max_uv maximum voltage in microvolts.
  *
- * @retval 0 If successful.
+ * @retval true If voltage is supported.
- * @retval -ENOSYS If function is not implemented.
+ * @retval false If voltage is not supported.
- * @retval -errno In case of any other error.
  */
-static inline int regulator_is_supported_voltage(const struct device *dev,
+bool regulator_is_supported_voltage(const struct device *dev, int32_t min_uv,
-						 int32_t min_uv, int32_t max_uv)
+				    int32_t max_uv);
-{
-	const struct regulator_driver_api *api =
-		(const struct regulator_driver_api *)dev->api;
-
-	if (api->is_supported_voltage == NULL) {
-		return -ENOSYS;
-	}
-
-	return api->is_supported_voltage(dev, min_uv, max_uv);
-}
 
 /**
  * @brief Set output voltage.