From 4d49367c5303e3ebd17502a45b74de280f6be539 Mon Sep 17 00:00:00 2001 From: Christian Lamparter Date: Sun, 13 Feb 2022 01:47:33 +0100 Subject: hwmon: (tc654) Add thermal_cooling device support Adds thermal_cooling device support to the tc654/tc655 driver. This make it possible to integrate it into a device-tree supported thermal-zone node as a cooling device. I have been using this patch as part of the Netgear WNDR4700 Centria NAS Router support within OpenWrt since 2016. Signed-off-by: Christian Lamparter Link: https://lore.kernel.org/r/20220213004733.2421193-1-chunkeey@gmail.com Signed-off-by: Guenter Roeck --- --- a/drivers/hwmon/tc654.c +++ b/drivers/hwmon/tc654.c @@ -15,6 +15,7 @@ #include #include #include +#include #include enum tc654_regs { @@ -379,28 +380,20 @@ static ssize_t pwm_show(struct device *d return sprintf(buf, "%d\n", pwm); } -static ssize_t pwm_store(struct device *dev, struct device_attribute *da, - const char *buf, size_t count) +static int _set_pwm(struct tc654_data *data, unsigned long val) { - struct tc654_data *data = dev_get_drvdata(dev); struct i2c_client *client = data->client; - unsigned long val; int ret; - if (kstrtoul(buf, 10, &val)) - return -EINVAL; - if (val > 255) - return -EINVAL; - mutex_lock(&data->update_lock); - if (val == 0) + if (val == 0) { data->config |= TC654_REG_CONFIG_SDM; - else + data->duty_cycle = 0; + } else { data->config &= ~TC654_REG_CONFIG_SDM; - - data->duty_cycle = find_closest(val, tc654_pwm_map, - ARRAY_SIZE(tc654_pwm_map)); + data->duty_cycle = val - 1; + } ret = i2c_smbus_write_byte_data(client, TC654_REG_CONFIG, data->config); if (ret < 0) @@ -411,6 +404,24 @@ static ssize_t pwm_store(struct device * out: mutex_unlock(&data->update_lock); + return ret; +} + +static ssize_t pwm_store(struct device *dev, struct device_attribute *da, + const char *buf, size_t count) +{ + struct tc654_data *data = dev_get_drvdata(dev); + unsigned long val; + int ret; + + if (kstrtoul(buf, 10, &val)) + return -EINVAL; + if (val > 255) + return -EINVAL; + if (val > 0) + val = find_closest(val, tc654_pwm_map, ARRAY_SIZE(tc654_pwm_map)) + 1; + + ret = _set_pwm(data, val); return ret < 0 ? ret : count; } @@ -443,6 +454,58 @@ static struct attribute *tc654_attrs[] = ATTRIBUTE_GROUPS(tc654); /* + * thermal cooling device functions + * + * Account for the "ShutDown Mode (SDM)" state by offsetting + * the 16 PWM duty cycle states by 1. + * + * State 0 = 0% PWM | Shutdown - Fan(s) are off + * State 1 = 30% PWM | duty_cycle = 0 + * State 2 = ~35% PWM | duty_cycle = 1 + * [...] + * State 15 = ~95% PWM | duty_cycle = 14 + * State 16 = 100% PWM | duty_cycle = 15 + */ +#define TC654_MAX_COOLING_STATE 16 + +static int tc654_get_max_state(struct thermal_cooling_device *cdev, unsigned long *state) +{ + *state = TC654_MAX_COOLING_STATE; + return 0; +} + +static int tc654_get_cur_state(struct thermal_cooling_device *cdev, unsigned long *state) +{ + struct tc654_data *data = tc654_update_client(cdev->devdata); + + if (IS_ERR(data)) + return PTR_ERR(data); + + if (data->config & TC654_REG_CONFIG_SDM) + *state = 0; /* FAN is off */ + else + *state = data->duty_cycle + 1; /* offset PWM States by 1 */ + + return 0; +} + +static int tc654_set_cur_state(struct thermal_cooling_device *cdev, unsigned long state) +{ + struct tc654_data *data = tc654_update_client(cdev->devdata); + + if (IS_ERR(data)) + return PTR_ERR(data); + + return _set_pwm(data, clamp_val(state, 0, TC654_MAX_COOLING_STATE)); +} + +static const struct thermal_cooling_device_ops tc654_fan_cool_ops = { + .get_max_state = tc654_get_max_state, + .get_cur_state = tc654_get_cur_state, + .set_cur_state = tc654_set_cur_state, +}; + +/* * device probe and removal */ @@ -472,7 +535,18 @@ static int tc654_probe(struct i2c_client hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name, data, tc654_groups); - return PTR_ERR_OR_ZERO(hwmon_dev); + if (IS_ERR(hwmon_dev)) + return PTR_ERR(hwmon_dev); + + if (IS_ENABLED(CONFIG_THERMAL)) { + struct thermal_cooling_device *cdev; + + cdev = devm_thermal_of_cooling_device_register(dev, dev->of_node, client->name, + hwmon_dev, &tc654_fan_cool_ops); + return PTR_ERR_OR_ZERO(cdev); + } + + return 0; } static const struct i2c_device_id tc654_id[] = {