On 08/26/2014 03:12 AM, Chanwoo Choi wrote:
Hi Jonghwa, On 08/26/2014 02:33 PM, Jonghwa Lee wrote:To get more comprehensive and integrated thermal management, it adds ntc thermistor to thermal framework as a thermal sensor. It's governed thermal susbsystem only if it is described in DT node. Otherwise, it just notifies temperature to userspace via sysfs as it used to be. Signed-off-by: Jonghwa Lee <jonghwa3.lee@xxxxxxxxxxx> --- .../devicetree/bindings/hwmon/ntc_thermistor.txt | 3 +++ drivers/hwmon/ntc_thermistor.c | 26 ++++++++++++++++++++ 2 files changed, 29 insertions(+) diff --git a/Documentation/devicetree/bindings/hwmon/ntc_thermistor.txt b/Documentation/devicetree/bindings/hwmon/ntc_thermistor.txt index 2391e5c..fcca8e7 100644 --- a/Documentation/devicetree/bindings/hwmon/ntc_thermistor.txt +++ b/Documentation/devicetree/bindings/hwmon/ntc_thermistor.txt @@ -25,6 +25,9 @@ Requires node properties: - "io-channels" Channel node of ADC to be used for conversion. +Optional node properties: +- "#thermal-sensor-cells" Used to expose itself to thermal fw. + Read more about iio bindings at Documentation/devicetree/bindings/iio/iio-bindings.txt diff --git a/drivers/hwmon/ntc_thermistor.c b/drivers/hwmon/ntc_thermistor.c index bd41072..369dc8c 100644 --- a/drivers/hwmon/ntc_thermistor.c +++ b/drivers/hwmon/ntc_thermistor.c @@ -38,6 +38,7 @@ #include <linux/hwmon.h> #include <linux/hwmon-sysfs.h> +#include <linux/thermal.h> struct ntc_compensation { int temp_c; @@ -182,6 +183,7 @@ struct ntc_data { struct device *dev; int n_comp; char name[PLATFORM_NAME_SIZE]; + struct thermal_zone_device *tz; }; #if defined(CONFIG_OF) && IS_ENABLED(CONFIG_IIO) @@ -428,6 +430,20 @@ static int ntc_thermistor_get_ohm(struct ntc_data *data) return -EINVAL; } +static int ntc_read_temp(void *dev, long *temp) +{ + struct ntc_data *data = dev_get_drvdata(dev); + int ohm; + + ohm = ntc_thermistor_get_ohm(data); + if (ohm < 0) + return ohm; + + *temp = get_temp_mc(data, ohm); + + return 0; +} + static ssize_t ntc_show_name(struct device *dev, struct device_attribute *attr, char *buf) { @@ -562,6 +578,13 @@ static int ntc_thermistor_probe(struct platform_device *pdev) dev_info(&pdev->dev, "Thermistor type: %s successfully probed.\n", pdev_id->name); + data->tz = thermal_zone_of_sensor_register(data->dev, 0, data->dev, + ntc_read_temp, NULL); + if (IS_ERR(data->tz)) { + dev_dbg(&pdev->dev, "Failed to register to thermal fw.\n"); + data->tz = NULL; + } + return 0; err_after_sysfs: sysfs_remove_group(&data->dev->kobj, &ntc_attr_group); @@ -578,6 +601,9 @@ static int ntc_thermistor_remove(struct platform_device *pdev) sysfs_remove_group(&data->dev->kobj, &ntc_attr_group); ntc_iio_channel_release(pdata); + if (data->tz) + thermal_zone_of_sensor_unregister(data->dev, data->tz);thermal_zone_of_sensor_unregister just return without operation if data->tz is NULL. So, don't need to check the value of data->tz with if statement.
On a side note, devm_thermal_zone_of_sensor_register would be quite useful to have. Guenter _______________________________________________ lm-sensors mailing list lm-sensors@xxxxxxxxxxxxxx http://lists.lm-sensors.org/mailman/listinfo/lm-sensors
