hwmon: (max6650) add thermal cooling device capability

This allows max6650 devices to be referenced in dts as a cooling device.

The pwm value seems duplicated in cooling_dev_state but since pwm goes
through rounding logic into data->dac, it is modified and messes with
the thermal zone state algorithms. It's also better to serve a cache
value, thus avoiding periodic actual i2c traffic.

Signed-off-by: Jean-Francois Dagenais <jeff.dagenais@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
This commit is contained in:
Jean-Francois Dagenais 2019-04-18 20:57:22 -04:00 committed by Guenter Roeck
parent 023912dbb8
commit 4f8d374b77
2 changed files with 90 additions and 1 deletions

View File

@ -908,6 +908,7 @@ config SENSORS_MAX6642
config SENSORS_MAX6650
tristate "Maxim MAX6650 sensor chip"
depends on I2C
depends on THERMAL || THERMAL=n
help
If you say yes here you get support for the MAX6650 / MAX6651
sensor chips.

View File

@ -40,6 +40,7 @@
#include <linux/hwmon-sysfs.h>
#include <linux/err.h>
#include <linux/of_device.h>
#include <linux/thermal.h>
/*
* Insmod parameters
@ -113,6 +114,7 @@ module_param(clock, int, 0444);
struct max6650_data {
struct i2c_client *client;
const struct attribute_group *groups[3];
struct thermal_cooling_device *cooling_dev;
struct mutex update_lock;
int nr_fans;
char valid; /* zero until following fields are valid */
@ -125,6 +127,7 @@ struct max6650_data {
u8 count;
u8 dac;
u8 alarm;
unsigned long cooling_dev_state;
};
static const u8 tach_reg[] = {
@ -694,6 +697,63 @@ static int max6650_init_client(struct max6650_data *data,
return 0;
}
#if IS_ENABLED(CONFIG_THERMAL)
static int max6650_get_max_state(struct thermal_cooling_device *cdev,
unsigned long *state)
{
*state = 255;
return 0;
}
static int max6650_get_cur_state(struct thermal_cooling_device *cdev,
unsigned long *state)
{
struct max6650_data *data = cdev->devdata;
*state = data->cooling_dev_state;
return 0;
}
static int max6650_set_cur_state(struct thermal_cooling_device *cdev,
unsigned long state)
{
struct max6650_data *data = cdev->devdata;
struct i2c_client *client = data->client;
int err;
state = clamp_val(state, 0, 255);
mutex_lock(&data->update_lock);
if (data->config & MAX6650_CFG_V12)
data->dac = 180 - (180 * state)/255;
else
data->dac = 76 - (76 * state)/255;
err = i2c_smbus_write_byte_data(client, MAX6650_REG_DAC, data->dac);
if (!err) {
max6650_set_operating_mode(data, state ?
MAX6650_CFG_MODE_OPEN_LOOP :
MAX6650_CFG_MODE_OFF);
data->cooling_dev_state = state;
}
mutex_unlock(&data->update_lock);
return err < 0 ? err : 0;
}
static const struct thermal_cooling_device_ops max6650_cooling_ops = {
.get_max_state = max6650_get_max_state,
.get_cur_state = max6650_get_cur_state,
.set_cur_state = max6650_set_cur_state,
};
#endif
static int max6650_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
@ -709,6 +769,7 @@ static int max6650_probe(struct i2c_client *client,
return -ENOMEM;
data->client = client;
i2c_set_clientdata(client, data);
mutex_init(&data->update_lock);
data->nr_fans = of_id ? (int)(uintptr_t)of_id->data : id->driver_data;
@ -727,7 +788,33 @@ static int max6650_probe(struct i2c_client *client,
hwmon_dev = devm_hwmon_device_register_with_groups(dev,
client->name, data,
data->groups);
return PTR_ERR_OR_ZERO(hwmon_dev);
err = PTR_ERR_OR_ZERO(hwmon_dev);
if (err)
return err;
#if IS_ENABLED(CONFIG_THERMAL)
data->cooling_dev =
thermal_of_cooling_device_register(client->dev.of_node,
client->name, data,
&max6650_cooling_ops);
if (IS_ERR(data->cooling_dev))
dev_warn(&client->dev,
"thermal cooling device register failed: %ld\n",
PTR_ERR(data->cooling_dev));
else
thermal_cdev_update(data->cooling_dev);
#endif
return 0;
}
static int max6650_remove(struct i2c_client *client)
{
struct max6650_data *data = i2c_get_clientdata(client);
if (!IS_ERR(data->cooling_dev))
thermal_cooling_device_unregister(data->cooling_dev);
return 0;
}
static const struct i2c_device_id max6650_id[] = {
@ -743,6 +830,7 @@ static struct i2c_driver max6650_driver = {
.of_match_table = of_match_ptr(max6650_dt_match),
},
.probe = max6650_probe,
.remove = max6650_remove,
.id_table = max6650_id,
};