From: Anson Huang <Anson.Huang@xxxxxxx>
On some platforms like i.MX8QXP, the thermal driver needs a
real HW sensor ID from DT thermal zone, the HW sensor ID is
used to get temperature from SCU firmware, and the virtual
sensor ID starting from 0 to N is NOT used at all, this patch
adds new API thermal_zone_of_get_sensor_id() to provide the
feature of getting sensor ID from DT thermal zone's node.
Signed-off-by: Anson Huang <Anson.Huang@xxxxxxx>
---
Changes since V12:
- allow the caller of thermal_zone_of_get_sensor_id() to pass NULL as second parameter
of_phandle_args structure, as some caller maybe ONLY need to read sensor ID.
---
drivers/thermal/of-thermal.c | 59 +++++++++++++++++++++++++++++++++++---------
include/linux/thermal.h | 10 ++++++++
2 files changed, 57 insertions(+), 12 deletions(-)
diff --git a/drivers/thermal/of-thermal.c b/drivers/thermal/of-thermal.c
index dc5093b..0466ab5 100644
--- a/drivers/thermal/of-thermal.c
+++ b/drivers/thermal/of-thermal.c
@@ -449,6 +449,52 @@ thermal_zone_of_add_sensor(struct device_node *zone,
}
/**
+ * thermal_zone_of_get_sensor_id - get sensor ID from a DT thermal zone
+ * @tz_np: a valid thermal zone device node.
+ * @sensor_specs: pointer to output arguments structure will be passed back,
+ * it can be NULL if the caller does NOT need the output
+ * arguments structure to be passed back.
+ * @id: a sensor ID pointer will be passed back.
+ *
+ * This function will get sensor ID from a given thermal zone node, use
+ * "thermal-sensors" as list name, and get sensor ID from first phandle's
+ * argument.
+ *
+ * Return: 0 on success, proper error code otherwise.
+ */
+
+int thermal_zone_of_get_sensor_id(struct device_node *tz_np,
+ struct of_phandle_args *sensor_specs,
+ u32 *id)
+{
+ struct of_phandle_args tmp_sensor_specs;
+ int ret;
+
+ if (!sensor_specs)
+ sensor_specs = &tmp_sensor_specs;
+
+ ret = of_parse_phandle_with_args(tz_np,
+ "thermal-sensors",
+ "#thermal-sensor-cells",
+ 0,
+ sensor_specs);
+ if (ret)
+ return ret;
+
+ if (sensor_specs->args_count >= 1) {
+ *id = sensor_specs->args[0];
+ WARN(sensor_specs->args_count > 1,
+ "%pOFn: too many cells in sensor specifier %d\n",
+ sensor_specs->np, sensor_specs->args_count);
+ } else {
+ *id = 0;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(thermal_zone_of_get_sensor_id);
+
+/**
* thermal_zone_of_sensor_register - registers a sensor to a DT thermal zone
* @dev: a valid struct device pointer of a sensor device. Must contain
* a valid .of_node, for the sensor node.
@@ -503,21 +549,10 @@ thermal_zone_of_sensor_register(struct device *dev, int sensor_id, void *data,
int ret, id;
/* For now, thermal framework supports only 1 sensor per zone */
- ret = of_parse_phandle_with_args(child, "thermal-sensors",
- "#thermal-sensor-cells",
- 0, &sensor_specs);
+ ret = thermal_zone_of_get_sensor_id(child, &sensor_specs, &id);
if (ret)
continue;
- if (sensor_specs.args_count >= 1) {
- id = sensor_specs.args[0];
- WARN(sensor_specs.args_count > 1,
- "%pOFn: too many cells in sensor specifier %d\n",
- sensor_specs.np, sensor_specs.args_count);
- } else {
- id = 0;
- }
-
if (sensor_specs.np == sensor_np && id == sensor_id) {
tzd = thermal_zone_of_add_sensor(child, sensor_np,
data, ops);
diff --git a/include/linux/thermal.h b/include/linux/thermal.h
index 15a4ca5..c994e3a 100644
--- a/include/linux/thermal.h
+++ b/include/linux/thermal.h
@@ -375,6 +375,9 @@ struct thermal_trip {
/* Function declarations */
#ifdef CONFIG_THERMAL_OF
+int thermal_zone_of_get_sensor_id(struct device_node *tz_np,
+ struct of_phandle_args *sensor_specs,
+ u32 *id);
struct thermal_zone_device *
thermal_zone_of_sensor_register(struct device *dev, int id, void *data,
const struct thermal_zone_of_device_ops *ops);
@@ -386,6 +389,13 @@ struct thermal_zone_device *devm_thermal_zone_of_sensor_register(
void devm_thermal_zone_of_sensor_unregister(struct device *dev,
struct thermal_zone_device *tz);
#else
+
+static int thermal_zone_of_get_sensor_id(struct device_node *tz_np,
+ struct of_phandle_args *sensor_specs,
+ u32 *id)
+{
+ return -ENOENT;
+}
static inline struct thermal_zone_device *
thermal_zone_of_sensor_register(struct device *dev, int id, void *data,
const struct thermal_zone_of_device_ops *ops)
--
2.7.4
