// SPDX-License-Identifier: GPL-2.0-or-later /* * max6639.c - Support for Maxim MAX6639 * * 2-Channel Temperature Monitor with Dual PWM Fan-Speed Controller * * Copyright (C) 2010, 2011 Roland Stigge * * based on the initial MAX6639 support from semptian.net * by He Changqing */ #include #include #include #include #include #include #include #include #include #include /* Addresses to scan */ static const unsigned short normal_i2c[] = { 0x2c, 0x2e, 0x2f, I2C_CLIENT_END }; /* The MAX6639 registers, valid channel numbers: 0, 1 */ #define MAX6639_REG_TEMP(ch) (0x00 + (ch)) #define MAX6639_REG_STATUS 0x02 #define MAX6639_REG_OUTPUT_MASK 0x03 #define MAX6639_REG_GCONFIG 0x04 #define MAX6639_REG_TEMP_EXT(ch) (0x05 + (ch)) #define MAX6639_REG_ALERT_LIMIT(ch) (0x08 + (ch)) #define MAX6639_REG_OT_LIMIT(ch) (0x0A + (ch)) #define MAX6639_REG_THERM_LIMIT(ch) (0x0C + (ch)) #define MAX6639_REG_FAN_CONFIG1(ch) (0x10 + (ch) * 4) #define MAX6639_REG_FAN_CONFIG2a(ch) (0x11 + (ch) * 4) #define MAX6639_REG_FAN_CONFIG2b(ch) (0x12 + (ch) * 4) #define MAX6639_REG_FAN_CONFIG3(ch) (0x13 + (ch) * 4) #define MAX6639_REG_FAN_CNT(ch) (0x20 + (ch)) #define MAX6639_REG_TARGET_CNT(ch) (0x22 + (ch)) #define MAX6639_REG_FAN_PPR(ch) (0x24 + (ch)) #define MAX6639_REG_TARGTDUTY(ch) (0x26 + (ch)) #define MAX6639_REG_FAN_START_TEMP(ch) (0x28 + (ch)) #define MAX6639_REG_DEVID 0x3D #define MAX6639_REG_MANUID 0x3E #define MAX6639_REG_DEVREV 0x3F /* Register bits */ #define MAX6639_GCONFIG_STANDBY 0x80 #define MAX6639_GCONFIG_POR 0x40 #define MAX6639_GCONFIG_DISABLE_TIMEOUT 0x20 #define MAX6639_GCONFIG_CH2_LOCAL 0x10 #define MAX6639_GCONFIG_PWM_FREQ_HI 0x08 #define MAX6639_FAN_CONFIG1_PWM 0x80 #define MAX6639_FAN_CONFIG3_THERM_FULL_SPEED 0x40 static const int rpm_ranges[] = { 2000, 4000, 8000, 16000 }; #define FAN_FROM_REG(val, rpm_range) ((val) == 0 || (val) == 255 ? \ 0 : (rpm_ranges[rpm_range] * 30) / (val)) #define TEMP_LIMIT_TO_REG(val) clamp_val((val) / 1000, 0, 255) /* * Client data (each client gets its own) */ struct max6639_data { struct i2c_client *client; struct mutex update_lock; bool valid; /* true if following fields are valid */ unsigned long last_updated; /* In jiffies */ /* Register values sampled regularly */ u16 temp[2]; /* Temperature, in 1/8 C, 0..255 C */ bool temp_fault[2]; /* Detected temperature diode failure */ u8 fan[2]; /* Register value: TACH count for fans >=30 */ u8 status; /* Detected channel alarms and fan failures */ /* Register values only written to */ u8 pwm[2]; /* Register value: Duty cycle 0..120 */ u8 temp_therm[2]; /* THERM Temperature, 0..255 C (->_max) */ u8 temp_alert[2]; /* ALERT Temperature, 0..255 C (->_crit) */ u8 temp_ot[2]; /* OT Temperature, 0..255 C (->_emergency) */ /* Register values initialized only once */ u8 ppr; /* Pulses per rotation 0..3 for 1..4 ppr */ u8 rpm_range; /* Index in above rpm_ranges table */ /* Optional regulator for FAN supply */ struct regulator *reg; }; static struct max6639_data *max6639_update_device(struct device *dev) { struct max6639_data *data = dev_get_drvdata(dev); struct i2c_client *client = data->client; struct max6639_data *ret = data; int i; int status_reg; mutex_lock(&data->update_lock); if (time_after(jiffies, data->last_updated + 2 * HZ) || !data->valid) { int res; dev_dbg(&client->dev, "Starting max6639 update\n"); status_reg = i2c_smbus_read_byte_data(client, MAX6639_REG_STATUS); if (status_reg < 0) { ret = ERR_PTR(status_reg); goto abort; } data->status = status_reg; for (i = 0; i < 2; i++) { res = i2c_smbus_read_byte_data(client, MAX6639_REG_FAN_CNT(i)); if (res < 0) { ret = ERR_PTR(res); goto abort; } data->fan[i] = res; res = i2c_smbus_read_byte_data(client, MAX6639_REG_TEMP_EXT(i)); if (res < 0) { ret = ERR_PTR(res); goto abort; } data->temp[i] = res >> 5; data->temp_fault[i] = res & 0x01; res = i2c_smbus_read_byte_data(client, MAX6639_REG_TEMP(i)); if (res < 0) { ret = ERR_PTR(res); goto abort; } data->temp[i] |= res << 3; } data->last_updated = jiffies; data->valid = true; } abort: mutex_unlock(&data->update_lock); return ret; } static ssize_t temp_input_show(struct device *dev, struct device_attribute *dev_attr, char *buf) { long temp; struct max6639_data *data = max6639_update_device(dev); struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr); if (IS_ERR(data)) return PTR_ERR(data); temp = data->temp[attr->index] * 125; return sprintf(buf, "%ld\n", temp); } static ssize_t temp_fault_show(struct device *dev, struct device_attribute *dev_attr, char *buf) { struct max6639_data *data = max6639_update_device(dev); struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr); if (IS_ERR(data)) return PTR_ERR(data); return sprintf(buf, "%d\n", data->temp_fault[attr->index]); } static ssize_t temp_max_show(struct device *dev, struct device_attribute *dev_attr, char *buf) { struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr); struct max6639_data *data = dev_get_drvdata(dev); return sprintf(buf, "%d\n", (data->temp_therm[attr->index] * 1000)); } static ssize_t temp_max_store(struct device *dev, struct device_attribute *dev_attr, const char *buf, size_t count) { struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr); struct max6639_data *data = dev_get_drvdata(dev); struct i2c_client *client = data->client; unsigned long val; int res; res = kstrtoul(buf, 10, &val); if (res) return res; mutex_lock(&data->update_lock); data->temp_therm[attr->index] = TEMP_LIMIT_TO_REG(val); i2c_smbus_write_byte_data(client, MAX6639_REG_THERM_LIMIT(attr->index), data->temp_therm[attr->index]); mutex_unlock(&data->update_lock); return count; } static ssize_t temp_crit_show(struct device *dev, struct device_attribute *dev_attr, char *buf) { struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr); struct max6639_data *data = dev_get_drvdata(dev); return sprintf(buf, "%d\n", (data->temp_alert[attr->index] * 1000)); } static ssize_t temp_crit_store(struct device *dev, struct device_attribute *dev_attr, const char *buf, size_t count) { struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr); struct max6639_data *data = dev_get_drvdata(dev); struct i2c_client *client = data->client; unsigned long val; int res; res = kstrtoul(buf, 10, &val); if (res) return res; mutex_lock(&data->update_lock); data->temp_alert[attr->index] = TEMP_LIMIT_TO_REG(val); i2c_smbus_write_byte_data(client, MAX6639_REG_ALERT_LIMIT(attr->index), data->temp_alert[attr->index]); mutex_unlock(&data->update_lock); return count; } static ssize_t temp_emergency_show(struct device *dev, struct device_attribute *dev_attr, char *buf) { struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr); struct max6639_data *data = dev_get_drvdata(dev); return sprintf(buf, "%d\n", (data->temp_ot[attr->index] * 1000)); } static ssize_t temp_emergency_store(struct device *dev, struct device_attribute *dev_attr, const char *buf, size_t count) { struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr); struct max6639_data *data = dev_get_drvdata(dev); struct i2c_client *client = data->client; unsigned long val; int res; res = kstrtoul(buf, 10, &val); if (res) return res; mutex_lock(&data->update_lock); data->temp_ot[attr->index] = TEMP_LIMIT_TO_REG(val); i2c_smbus_write_byte_data(client, MAX6639_REG_OT_LIMIT(attr->index), data->temp_ot[attr->index]); mutex_unlock(&data->update_lock); return count; } static ssize_t pwm_show(struct device *dev, struct device_attribute *dev_attr, char *buf) { struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr); struct max6639_data *data = dev_get_drvdata(dev); return sprintf(buf, "%d\n", data->pwm[attr->index] * 255 / 120); } static ssize_t pwm_store(struct device *dev, struct device_attribute *dev_attr, const char *buf, size_t count) { struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr); struct max6639_data *data = dev_get_drvdata(dev); struct i2c_client *client = data->client; unsigned long val; int res; res = kstrtoul(buf, 10, &val); if (res) return res; val = clamp_val(val, 0, 255); mutex_lock(&data->update_lock); data->pwm[attr->index] = (u8)(val * 120 / 255); i2c_smbus_write_byte_data(client, MAX6639_REG_TARGTDUTY(attr->index), data->pwm[attr->index]); mutex_unlock(&data->update_lock); return count; } static ssize_t fan_input_show(struct device *dev, struct device_attribute *dev_attr, char *buf) { struct max6639_data *data = max6639_update_device(dev); struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr); if (IS_ERR(data)) return PTR_ERR(data); return sprintf(buf, "%d\n", FAN_FROM_REG(data->fan[attr->index], data->rpm_range)); } static ssize_t alarm_show(struct device *dev, struct device_attribute *dev_attr, char *buf) { struct max6639_data *data = max6639_update_device(dev); struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr); if (IS_ERR(data)) return PTR_ERR(data); return sprintf(buf, "%d\n", !!(data->status & (1 << attr->index))); } static SENSOR_DEVICE_ATTR_RO(temp1_input, temp_input, 0); static SENSOR_DEVICE_ATTR_RO(temp2_input, temp_input, 1); static SENSOR_DEVICE_ATTR_RO(temp1_fault, temp_fault, 0); static SENSOR_DEVICE_ATTR_RO(temp2_fault, temp_fault, 1); static SENSOR_DEVICE_ATTR_RW(temp1_max, temp_max, 0); static SENSOR_DEVICE_ATTR_RW(temp2_max, temp_max, 1); static SENSOR_DEVICE_ATTR_RW(temp1_crit, temp_crit, 0); static SENSOR_DEVICE_ATTR_RW(temp2_crit, temp_crit, 1); static SENSOR_DEVICE_ATTR_RW(temp1_emergency, temp_emergency, 0); static SENSOR_DEVICE_ATTR_RW(temp2_emergency, temp_emergency, 1); static SENSOR_DEVICE_ATTR_RW(pwm1, pwm, 0); static SENSOR_DEVICE_ATTR_RW(pwm2, pwm, 1); static SENSOR_DEVICE_ATTR_RO(fan1_input, fan_input, 0); static SENSOR_DEVICE_ATTR_RO(fan2_input, fan_input, 1); static SENSOR_DEVICE_ATTR_RO(fan1_fault, alarm, 1); static SENSOR_DEVICE_ATTR_RO(fan2_fault, alarm, 0); static SENSOR_DEVICE_ATTR_RO(temp1_max_alarm, alarm, 3); static SENSOR_DEVICE_ATTR_RO(temp2_max_alarm, alarm, 2); static SENSOR_DEVICE_ATTR_RO(temp1_crit_alarm, alarm, 7); static SENSOR_DEVICE_ATTR_RO(temp2_crit_alarm, alarm, 6); static SENSOR_DEVICE_ATTR_RO(temp1_emergency_alarm, alarm, 5); static SENSOR_DEVICE_ATTR_RO(temp2_emergency_alarm, alarm, 4); static struct attribute *max6639_attrs[] = { &sensor_dev_attr_temp1_input.dev_attr.attr, &sensor_dev_attr_temp2_input.dev_attr.attr, &sensor_dev_attr_temp1_fault.dev_attr.attr, &sensor_dev_attr_temp2_fault.dev_attr.attr, &sensor_dev_attr_temp1_max.dev_attr.attr, &sensor_dev_attr_temp2_max.dev_attr.attr, &sensor_dev_attr_temp1_crit.dev_attr.attr, &sensor_dev_attr_temp2_crit.dev_attr.attr, &sensor_dev_attr_temp1_emergency.dev_attr.attr, &sensor_dev_attr_temp2_emergency.dev_attr.attr, &sensor_dev_attr_pwm1.dev_attr.attr, &sensor_dev_attr_pwm2.dev_attr.attr, &sensor_dev_attr_fan1_input.dev_attr.attr, &sensor_dev_attr_fan2_input.dev_attr.attr, &sensor_dev_attr_fan1_fault.dev_attr.attr, &sensor_dev_attr_fan2_fault.dev_attr.attr, &sensor_dev_attr_temp1_max_alarm.dev_attr.attr, &sensor_dev_attr_temp2_max_alarm.dev_attr.attr, &sensor_dev_attr_temp1_crit_alarm.dev_attr.attr, &sensor_dev_attr_temp2_crit_alarm.dev_attr.attr, &sensor_dev_attr_temp1_emergency_alarm.dev_attr.attr, &sensor_dev_attr_temp2_emergency_alarm.dev_attr.attr, NULL }; ATTRIBUTE_GROUPS(max6639); /* * returns respective index in rpm_ranges table * 1 by default on invalid range */ static int rpm_range_to_reg(int range) { int i; for (i = 0; i < ARRAY_SIZE(rpm_ranges); i++) { if (rpm_ranges[i] == range) return i; } return 1; /* default: 4000 RPM */ } static int max6639_init_client(struct i2c_client *client, struct max6639_data *data) { struct max6639_platform_data *max6639_info = dev_get_platdata(&client->dev); int i; int rpm_range = 1; /* default: 4000 RPM */ int err; /* Reset chip to default values, see below for GCONFIG setup */ err = i2c_smbus_write_byte_data(client, MAX6639_REG_GCONFIG, MAX6639_GCONFIG_POR); if (err) goto exit; /* Fans pulse per revolution is 2 by default */ if (max6639_info && max6639_info->ppr > 0 && max6639_info->ppr < 5) data->ppr = max6639_info->ppr; else data->ppr = 2; data->ppr -= 1; if (max6639_info) rpm_range = rpm_range_to_reg(max6639_info->rpm_range); data->rpm_range = rpm_range; for (i = 0; i < 2; i++) { /* Set Fan pulse per revolution */ err = i2c_smbus_write_byte_data(client, MAX6639_REG_FAN_PPR(i), data->ppr << 6); if (err) goto exit; /* Fans config PWM, RPM */ err = i2c_smbus_write_byte_data(client, MAX6639_REG_FAN_CONFIG1(i), MAX6639_FAN_CONFIG1_PWM | rpm_range); if (err) goto exit; /* Fans PWM polarity high by default */ if (max6639_info && max6639_info->pwm_polarity == 0) err = i2c_smbus_write_byte_data(client, MAX6639_REG_FAN_CONFIG2a(i), 0x00); else err = i2c_smbus_write_byte_data(client, MAX6639_REG_FAN_CONFIG2a(i), 0x02); if (err) goto exit; /* * /THERM full speed enable, * PWM frequency 25kHz, see also GCONFIG below */ err = i2c_smbus_write_byte_data(client, MAX6639_REG_FAN_CONFIG3(i), MAX6639_FAN_CONFIG3_THERM_FULL_SPEED | 0x03); if (err) goto exit; /* Max. temp. 80C/90C/100C */ data->temp_therm[i] = 80; data->temp_alert[i] = 90; data->temp_ot[i] = 100; err = i2c_smbus_write_byte_data(client, MAX6639_REG_THERM_LIMIT(i), data->temp_therm[i]); if (err) goto exit; err = i2c_smbus_write_byte_data(client, MAX6639_REG_ALERT_LIMIT(i), data->temp_alert[i]); if (err) goto exit; err = i2c_smbus_write_byte_data(client, MAX6639_REG_OT_LIMIT(i), data->temp_ot[i]); if (err) goto exit; /* PWM 120/120 (i.e. 100%) */ data->pwm[i] = 120; err = i2c_smbus_write_byte_data(client, MAX6639_REG_TARGTDUTY(i), data->pwm[i]); if (err) goto exit; } /* Start monitoring */ err = i2c_smbus_write_byte_data(client, MAX6639_REG_GCONFIG, MAX6639_GCONFIG_DISABLE_TIMEOUT | MAX6639_GCONFIG_CH2_LOCAL | MAX6639_GCONFIG_PWM_FREQ_HI); exit: return err; } /* Return 0 if detection is successful, -ENODEV otherwise */ static int max6639_detect(struct i2c_client *client, struct i2c_board_info *info) { struct i2c_adapter *adapter = client->adapter; int dev_id, manu_id; if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) return -ENODEV; /* Actual detection via device and manufacturer ID */ dev_id = i2c_smbus_read_byte_data(client, MAX6639_REG_DEVID); manu_id = i2c_smbus_read_byte_data(client, MAX6639_REG_MANUID); if (dev_id != 0x58 || manu_id != 0x4D) return -ENODEV; strscpy(info->type, "max6639", I2C_NAME_SIZE); return 0; } static void max6639_regulator_disable(void *data) { regulator_disable(data); } static int max6639_probe(struct i2c_client *client) { struct device *dev = &client->dev; struct max6639_data *data; struct device *hwmon_dev; int err; data = devm_kzalloc(dev, sizeof(struct max6639_data), GFP_KERNEL); if (!data) return -ENOMEM; data->client = client; data->reg = devm_regulator_get_optional(dev, "fan"); if (IS_ERR(data->reg)) { if (PTR_ERR(data->reg) != -ENODEV) return PTR_ERR(data->reg); data->reg = NULL; } else { /* Spin up fans */ err = regulator_enable(data->reg); if (err) { dev_err(dev, "Failed to enable fan supply: %d\n", err); return err; } err = devm_add_action_or_reset(dev, max6639_regulator_disable, data->reg); if (err) { dev_err(dev, "Failed to register action: %d\n", err); return err; } } mutex_init(&data->update_lock); /* Initialize the max6639 chip */ err = max6639_init_client(client, data); if (err < 0) return err; hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name, data, max6639_groups); return PTR_ERR_OR_ZERO(hwmon_dev); } #ifdef CONFIG_PM_SLEEP static int max6639_suspend(struct device *dev) { struct i2c_client *client = to_i2c_client(dev); struct max6639_data *data = dev_get_drvdata(dev); int ret = i2c_smbus_read_byte_data(client, MAX6639_REG_GCONFIG); if (ret < 0) return ret; if (data->reg) regulator_disable(data->reg); return i2c_smbus_write_byte_data(client, MAX6639_REG_GCONFIG, ret | MAX6639_GCONFIG_STANDBY); } static int max6639_resume(struct device *dev) { struct i2c_client *client = to_i2c_client(dev); struct max6639_data *data = dev_get_drvdata(dev); int ret; if (data->reg) { ret = regulator_enable(data->reg); if (ret) { dev_err(dev, "Failed to enable fan supply: %d\n", ret); return ret; } } ret = i2c_smbus_read_byte_data(client, MAX6639_REG_GCONFIG); if (ret < 0) return ret; return i2c_smbus_write_byte_data(client, MAX6639_REG_GCONFIG, ret & ~MAX6639_GCONFIG_STANDBY); } #endif /* CONFIG_PM_SLEEP */ static const struct i2c_device_id max6639_id[] = { {"max6639", 0}, { } }; MODULE_DEVICE_TABLE(i2c, max6639_id); static SIMPLE_DEV_PM_OPS(max6639_pm_ops, max6639_suspend, max6639_resume); static struct i2c_driver max6639_driver = { .class = I2C_CLASS_HWMON, .driver = { .name = "max6639", .pm = &max6639_pm_ops, }, .probe_new = max6639_probe, .id_table = max6639_id, .detect = max6639_detect, .address_list = normal_i2c, }; module_i2c_driver(max6639_driver); MODULE_AUTHOR("Roland Stigge "); MODULE_DESCRIPTION("max6639 driver"); MODULE_LICENSE("GPL");