Re: [PATCH V15 RESEND 2/5] thermal: of-thermal: add API for getting sensor ID from DT

Daniel Lezcano
2020-02-21T09:11:20Z

Hi,

On Thu, Feb 20, 2020 at 09:10:25AM +0800, Anson Huang wrote:
> 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. It's useful for thermal driver to register the
> specific thermal zone devices from DT in a common way.
>
> Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
> Reviewed-by: Dong Aisheng <aisheng.dong@nxp.com>
> ---
> Changes since V14:
> - improve the commit message and comment, no code change.
> ---
> drivers/thermal/of-thermal.c | 65 +++++++++++++++++++++++++++++++++-----------
> include/linux/thermal.h | 10 +++++++
> 2 files changed, 59 insertions(+), 16 deletions(-)
>
> diff --git a/drivers/thermal/of-thermal.c b/drivers/thermal/of-thermal.c
> index ef0baa9..0f57108 100644
> --- a/drivers/thermal/of-thermal.c
> +++ b/drivers/thermal/of-thermal.c
> @@ -449,6 +449,53 @@ 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_np: a sensor node of a valid sensor device.
> + * @id: the sensor ID returned if success.
> + *
> + * This function will get sensor ID from a given thermal zone node and
> + * the sensor node must match the temperature provider @sensor_np.
> + *
> + * Return: 0 on success, proper error code otherwise.
> + */
> +
> +int thermal_zone_of_get_sensor_id(struct device_node *tz_np,
> + struct device_node *sensor_np,
> + u32 *id)
> +{
> + struct of_phandle_args sensor_specs;
> + int ret;
> +
> + ret = of_parse_phandle_with_args(tz_np,
> + "thermal-sensors",
> + "#thermal-sensor-cells",
> + 0,
> + &sensor_specs);
> + if (ret)
> + return ret;
> +
> + if (sensor_specs.np != sensor_np) {
> + of_node_put(sensor_specs.np);
> + return -ENODEV;
> + }
> +
> + if (sensor_specs.args_count >= 1) {

For the sake of clarity, move the sanity tests before:

if (sensor_specs.args_count > 1)
pr_warn("...");

*id = sensor_specs.args_count ? sensor_specs.args[0] : 0;

> + *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;
> + }
> +
> + of_node_put(sensor_specs.np);
> +
> + 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.
> @@ -499,36 +546,22 @@ thermal_zone_of_sensor_register(struct device *dev, int sensor_id, void *data,
> sensor_np = of_node_get(dev->of_node);
>
> for_each_available_child_of_node(np, child) {
> - struct of_phandle_args sensor_specs;
> 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_np, &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;
> - }

Please take also the opportunity to factor out the function
thermal_zone_of_sensor_register().

> - if (sensor_specs.np == sensor_np && id == sensor_id) {
> + if (id == sensor_id) {
> tzd = thermal_zone_of_add_sensor(child, sensor_np,
> data, ops);
> if (!IS_ERR(tzd))
> tzd->ops->set_mode(tzd, THERMAL_DEVICE_ENABLED);
>
> - of_node_put(sensor_specs.np);
> of_node_put(child);
> goto exit;
> }
> - of_node_put(sensor_specs.np);
> }
> exit:
> of_node_put(sensor_np);
> diff --git a/include/linux/thermal.h b/include/linux/thermal.h
> index 126913c6..53e6f67 100644
> --- a/include/linux/thermal.h
> +++ b/include/linux/thermal.h
> @@ -364,6 +364,9 @@ struct thermal_trip {
>
> /* Function declarations */
> #ifdef CONFIG_THERMAL_OF
> +int thermal_zone_of_get_sensor_id(struct device_node *tz_np,
> + struct device_node *sensor_np,
> + 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);
> @@ -375,6 +378,13 @@ 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 device_node *sensor_np,
> + 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
>

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