From 4f8d374b770a2e26088186d6c18acf582227129d Mon Sep 17 00:00:00 2001 From: Jean-Francois Dagenais Date: Thu, 18 Apr 2019 20:57:22 -0400 Subject: [PATCH] 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 Signed-off-by: Guenter Roeck --- drivers/hwmon/Kconfig | 1 + drivers/hwmon/max6650.c | 90 ++++++++++++++++++++++++++++++++++++++++- 2 files changed, 90 insertions(+), 1 deletion(-) diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig index 470ba66b18b0..1915a18b537b 100644 --- a/drivers/hwmon/Kconfig +++ b/drivers/hwmon/Kconfig @@ -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. diff --git a/drivers/hwmon/max6650.c b/drivers/hwmon/max6650.c index 95b234631e55..e977c2f2d74a 100644 --- a/drivers/hwmon/max6650.c +++ b/drivers/hwmon/max6650.c @@ -40,6 +40,7 @@ #include #include #include +#include /* * 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, };