// 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 #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_FREQ_MASK 0x03 #define MAX6639_FAN_CONFIG3_THERM_FULL_SPEED 0x40 #define MAX6639_NUM_CHANNELS 2 static const int rpm_ranges[] = { 2000, 4000, 8000, 16000 }; /* Supported PWM frequency */ static const unsigned int freq_table[] = { 20, 33, 50, 100, 5000, 8333, 12500, 25000 }; #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 regmap *regmap; struct mutex update_lock; /* Register values initialized only once */ u8 ppr[MAX6639_NUM_CHANNELS]; /* Pulses per rotation 0..3 for 1..4 ppr */ u8 rpm_range[MAX6639_NUM_CHANNELS]; /* Index in above rpm_ranges table */ /* Optional regulator for FAN supply */ struct regulator *reg; }; static int max6639_temp_read_input(struct device *dev, int channel, long *temp) { u32 regs[2] = { MAX6639_REG_TEMP_EXT(channel), MAX6639_REG_TEMP(channel) }; struct max6639_data *data = dev_get_drvdata(dev); u8 regvals[2]; int res; res = regmap_multi_reg_read(data->regmap, regs, regvals, 2); if (res < 0) return res; *temp = ((regvals[0] >> 5) | (regvals[1] << 3)) * 125; return 0; } static int max6639_temp_read_fault(struct device *dev, int channel, long *fault) { struct max6639_data *data = dev_get_drvdata(dev); unsigned int val; int res; res = regmap_read(data->regmap, MAX6639_REG_TEMP_EXT(channel), &val); if (res < 0) return res; *fault = val & 1; return 0; } static int max6639_temp_read_max(struct device *dev, int channel, long *max) { struct max6639_data *data = dev_get_drvdata(dev); unsigned int val; int res; res = regmap_read(data->regmap, MAX6639_REG_THERM_LIMIT(channel), &val); if (res < 0) return res; *max = (long)val * 1000; return 0; } static int max6639_temp_read_crit(struct device *dev, int channel, long *crit) { struct max6639_data *data = dev_get_drvdata(dev); unsigned int val; int res; res = regmap_read(data->regmap, MAX6639_REG_ALERT_LIMIT(channel), &val); if (res < 0) return res; *crit = (long)val * 1000; return 0; } static int max6639_temp_read_emergency(struct device *dev, int channel, long *emerg) { struct max6639_data *data = dev_get_drvdata(dev); unsigned int val; int res; res = regmap_read(data->regmap, MAX6639_REG_OT_LIMIT(channel), &val); if (res < 0) return res; *emerg = (long)val * 1000; return 0; } static int max6639_get_status(struct device *dev, unsigned int *status) { struct max6639_data *data = dev_get_drvdata(dev); unsigned int val; int res; res = regmap_read(data->regmap, MAX6639_REG_STATUS, &val); if (res < 0) return res; *status = val; return 0; } static int max6639_temp_set_max(struct max6639_data *data, int channel, long val) { int res; res = regmap_write(data->regmap, MAX6639_REG_THERM_LIMIT(channel), TEMP_LIMIT_TO_REG(val)); return res; } static int max6639_temp_set_crit(struct max6639_data *data, int channel, long val) { int res; res = regmap_write(data->regmap, MAX6639_REG_ALERT_LIMIT(channel), TEMP_LIMIT_TO_REG(val)); return res; } static int max6639_temp_set_emergency(struct max6639_data *data, int channel, long val) { int res; res = regmap_write(data->regmap, MAX6639_REG_OT_LIMIT(channel), TEMP_LIMIT_TO_REG(val)); return res; } static int max6639_read_fan(struct device *dev, u32 attr, int channel, long *fan_val) { struct max6639_data *data = dev_get_drvdata(dev); unsigned int val; int res; switch (attr) { case hwmon_fan_input: res = regmap_read(data->regmap, MAX6639_REG_FAN_CNT(channel), &val); if (res < 0) return res; *fan_val = FAN_FROM_REG(val, data->rpm_range[channel]); return 0; case hwmon_fan_fault: res = max6639_get_status(dev, &val); if (res < 0) return res; *fan_val = !!(val & BIT(1 - channel)); return 0; case hwmon_fan_pulses: *fan_val = data->ppr[channel]; return 0; default: return -EOPNOTSUPP; } } static int max6639_set_ppr(struct max6639_data *data, int channel, u8 ppr) { /* Decrement the PPR value and shift left by 6 to match the register format */ return regmap_write(data->regmap, MAX6639_REG_FAN_PPR(channel), ppr-- << 6); } static int max6639_write_fan(struct device *dev, u32 attr, int channel, long val) { struct max6639_data *data = dev_get_drvdata(dev); int err; switch (attr) { case hwmon_fan_pulses: if (val <= 0 || val > 4) return -EINVAL; mutex_lock(&data->update_lock); /* Set Fan pulse per revolution */ err = max6639_set_ppr(data, channel, val); if (err < 0) { mutex_unlock(&data->update_lock); return err; } data->ppr[channel] = val; mutex_unlock(&data->update_lock); return 0; default: return -EOPNOTSUPP; } } static umode_t max6639_fan_is_visible(const void *_data, u32 attr, int channel) { switch (attr) { case hwmon_fan_input: case hwmon_fan_fault: return 0444; case hwmon_fan_pulses: return 0644; default: return 0; } } static int max6639_read_pwm(struct device *dev, u32 attr, int channel, long *pwm_val) { u32 regs[2] = { MAX6639_REG_FAN_CONFIG3(channel), MAX6639_REG_GCONFIG }; struct max6639_data *data = dev_get_drvdata(dev); unsigned int val; u8 regvals[2]; int res; u8 i; switch (attr) { case hwmon_pwm_input: res = regmap_read(data->regmap, MAX6639_REG_TARGTDUTY(channel), &val); if (res < 0) return res; *pwm_val = val * 255 / 120; return 0; case hwmon_pwm_freq: res = regmap_multi_reg_read(data->regmap, regs, regvals, 2); if (res < 0) return res; i = regvals[0] & MAX6639_FAN_CONFIG3_FREQ_MASK; if (regvals[1] & MAX6639_GCONFIG_PWM_FREQ_HI) i |= 0x4; *pwm_val = freq_table[i]; return 0; default: return -EOPNOTSUPP; } } static int max6639_write_pwm(struct device *dev, u32 attr, int channel, long val) { struct max6639_data *data = dev_get_drvdata(dev); int err; u8 i; switch (attr) { case hwmon_pwm_input: if (val < 0 || val > 255) return -EINVAL; err = regmap_write(data->regmap, MAX6639_REG_TARGTDUTY(channel), val * 120 / 255); return err; case hwmon_pwm_freq: val = clamp_val(val, 0, 25000); i = find_closest(val, freq_table, ARRAY_SIZE(freq_table)); mutex_lock(&data->update_lock); err = regmap_update_bits(data->regmap, MAX6639_REG_FAN_CONFIG3(channel), MAX6639_FAN_CONFIG3_FREQ_MASK, i); if (err < 0) { mutex_unlock(&data->update_lock); return err; } if (i >> 2) err = regmap_set_bits(data->regmap, MAX6639_REG_GCONFIG, MAX6639_GCONFIG_PWM_FREQ_HI); else err = regmap_clear_bits(data->regmap, MAX6639_REG_GCONFIG, MAX6639_GCONFIG_PWM_FREQ_HI); mutex_unlock(&data->update_lock); return err; default: return -EOPNOTSUPP; } } static umode_t max6639_pwm_is_visible(const void *_data, u32 attr, int channel) { switch (attr) { case hwmon_pwm_input: case hwmon_pwm_freq: return 0644; default: return 0; } } static int max6639_read_temp(struct device *dev, u32 attr, int channel, long *val) { unsigned int status; int res; switch (attr) { case hwmon_temp_input: res = max6639_temp_read_input(dev, channel, val); return res; case hwmon_temp_fault: res = max6639_temp_read_fault(dev, channel, val); return res; case hwmon_temp_max: res = max6639_temp_read_max(dev, channel, val); return res; case hwmon_temp_crit: res = max6639_temp_read_crit(dev, channel, val); return res; case hwmon_temp_emergency: res = max6639_temp_read_emergency(dev, channel, val); return res; case hwmon_temp_max_alarm: res = max6639_get_status(dev, &status); if (res < 0) return res; *val = !!(status & BIT(3 - channel)); return 0; case hwmon_temp_crit_alarm: res = max6639_get_status(dev, &status); if (res < 0) return res; *val = !!(status & BIT(7 - channel)); return 0; case hwmon_temp_emergency_alarm: res = max6639_get_status(dev, &status); if (res < 0) return res; *val = !!(status & BIT(5 - channel)); return 0; default: return -EOPNOTSUPP; } } static int max6639_write_temp(struct device *dev, u32 attr, int channel, long val) { struct max6639_data *data = dev_get_drvdata(dev); switch (attr) { case hwmon_temp_max: return max6639_temp_set_max(data, channel, val); case hwmon_temp_crit: return max6639_temp_set_crit(data, channel, val); case hwmon_temp_emergency: return max6639_temp_set_emergency(data, channel, val); default: return -EOPNOTSUPP; } } static umode_t max6639_temp_is_visible(const void *_data, u32 attr, int channel) { switch (attr) { case hwmon_temp_input: case hwmon_temp_fault: case hwmon_temp_max_alarm: case hwmon_temp_crit_alarm: case hwmon_temp_emergency_alarm: return 0444; case hwmon_temp_max: case hwmon_temp_crit: case hwmon_temp_emergency: return 0644; default: return 0; } } static int max6639_read(struct device *dev, enum hwmon_sensor_types type, u32 attr, int channel, long *val) { switch (type) { case hwmon_fan: return max6639_read_fan(dev, attr, channel, val); case hwmon_pwm: return max6639_read_pwm(dev, attr, channel, val); case hwmon_temp: return max6639_read_temp(dev, attr, channel, val); default: return -EOPNOTSUPP; } } static int max6639_write(struct device *dev, enum hwmon_sensor_types type, u32 attr, int channel, long val) { switch (type) { case hwmon_fan: return max6639_write_fan(dev, attr, channel, val); case hwmon_pwm: return max6639_write_pwm(dev, attr, channel, val); case hwmon_temp: return max6639_write_temp(dev, attr, channel, val); default: return -EOPNOTSUPP; } } static umode_t max6639_is_visible(const void *data, enum hwmon_sensor_types type, u32 attr, int channel) { switch (type) { case hwmon_fan: return max6639_fan_is_visible(data, attr, channel); case hwmon_pwm: return max6639_pwm_is_visible(data, attr, channel); case hwmon_temp: return max6639_temp_is_visible(data, attr, channel); default: return 0; } } static const struct hwmon_channel_info * const max6639_info[] = { HWMON_CHANNEL_INFO(fan, HWMON_F_INPUT | HWMON_F_FAULT | HWMON_F_PULSES, HWMON_F_INPUT | HWMON_F_FAULT | HWMON_F_PULSES), HWMON_CHANNEL_INFO(pwm, HWMON_PWM_INPUT | HWMON_PWM_FREQ, HWMON_PWM_INPUT | HWMON_PWM_FREQ), HWMON_CHANNEL_INFO(temp, HWMON_T_INPUT | HWMON_T_FAULT | HWMON_T_MAX | HWMON_T_MAX_ALARM | HWMON_T_CRIT | HWMON_T_CRIT_ALARM | HWMON_T_EMERGENCY | HWMON_T_EMERGENCY_ALARM, HWMON_T_INPUT | HWMON_T_FAULT | HWMON_T_MAX | HWMON_T_MAX_ALARM | HWMON_T_CRIT | HWMON_T_CRIT_ALARM | HWMON_T_EMERGENCY | HWMON_T_EMERGENCY_ALARM), NULL }; static const struct hwmon_ops max6639_hwmon_ops = { .is_visible = max6639_is_visible, .read = max6639_read, .write = max6639_write, }; static const struct hwmon_chip_info max6639_chip_info = { .ops = &max6639_hwmon_ops, .info = max6639_info, }; /* * 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_probe_child_from_dt(struct i2c_client *client, struct device_node *child, struct max6639_data *data) { struct device *dev = &client->dev; u32 i; int err, val; err = of_property_read_u32(child, "reg", &i); if (err) { dev_err(dev, "missing reg property of %pOFn\n", child); return err; } if (i > 1) { dev_err(dev, "Invalid fan index reg %d\n", i); return -EINVAL; } err = of_property_read_u32(child, "pulses-per-revolution", &val); if (!err) { if (val < 1 || val > 5) { dev_err(dev, "invalid pulses-per-revolution %d of %pOFn\n", val, child); return -EINVAL; } data->ppr[i] = val; } err = of_property_read_u32(child, "max-rpm", &val); if (!err) data->rpm_range[i] = rpm_range_to_reg(val); return 0; } static int max6639_init_client(struct i2c_client *client, struct max6639_data *data) { struct device *dev = &client->dev; const struct device_node *np = dev->of_node; struct device_node *child; int i, err; /* Reset chip to default values, see below for GCONFIG setup */ err = regmap_write(data->regmap, MAX6639_REG_GCONFIG, MAX6639_GCONFIG_POR); if (err) return err; /* Fans pulse per revolution is 2 by default */ data->ppr[0] = 2; data->ppr[1] = 2; /* default: 4000 RPM */ data->rpm_range[0] = 1; data->rpm_range[1] = 1; for_each_child_of_node(np, child) { if (strcmp(child->name, "fan")) continue; err = max6639_probe_child_from_dt(client, child, data); if (err) { of_node_put(child); return err; } } for (i = 0; i < MAX6639_NUM_CHANNELS; i++) { err = regmap_set_bits(data->regmap, MAX6639_REG_OUTPUT_MASK, BIT(1 - i)); if (err) return err; /* Set Fan pulse per revolution */ err = max6639_set_ppr(data, i, data->ppr[i]); if (err) return err; /* Fans config PWM, RPM */ err = regmap_write(data->regmap, MAX6639_REG_FAN_CONFIG1(i), MAX6639_FAN_CONFIG1_PWM | data->rpm_range[i]); if (err) return err; /* Fans PWM polarity high by default */ err = regmap_write(data->regmap, MAX6639_REG_FAN_CONFIG2a(i), 0x00); if (err) return err; /* * /THERM full speed enable, * PWM frequency 25kHz, see also GCONFIG below */ err = regmap_write(data->regmap, MAX6639_REG_FAN_CONFIG3(i), MAX6639_FAN_CONFIG3_THERM_FULL_SPEED | 0x03); if (err) return err; /* Max. temp. 80C/90C/100C */ err = regmap_write(data->regmap, MAX6639_REG_THERM_LIMIT(i), 80); if (err) return err; err = regmap_write(data->regmap, MAX6639_REG_ALERT_LIMIT(i), 90); if (err) return err; err = regmap_write(data->regmap, MAX6639_REG_OT_LIMIT(i), 100); if (err) return err; /* PWM 120/120 (i.e. 100%) */ err = regmap_write(data->regmap, MAX6639_REG_TARGTDUTY(i), 120); if (err) return err; } /* Start monitoring */ return regmap_write(data->regmap, MAX6639_REG_GCONFIG, MAX6639_GCONFIG_DISABLE_TIMEOUT | MAX6639_GCONFIG_CH2_LOCAL | MAX6639_GCONFIG_PWM_FREQ_HI); } /* 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 bool max6639_regmap_is_volatile(struct device *dev, unsigned int reg) { switch (reg) { case MAX6639_REG_TEMP(0): case MAX6639_REG_TEMP_EXT(0): case MAX6639_REG_TEMP(1): case MAX6639_REG_TEMP_EXT(1): case MAX6639_REG_STATUS: case MAX6639_REG_FAN_CNT(0): case MAX6639_REG_FAN_CNT(1): case MAX6639_REG_TARGTDUTY(0): case MAX6639_REG_TARGTDUTY(1): return true; default: return false; } } static const struct regmap_config max6639_regmap_config = { .reg_bits = 8, .val_bits = 8, .max_register = MAX6639_REG_DEVREV, .cache_type = REGCACHE_MAPLE, .volatile_reg = max6639_regmap_is_volatile, }; 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->regmap = devm_regmap_init_i2c(client, &max6639_regmap_config); if (IS_ERR(data->regmap)) return dev_err_probe(dev, PTR_ERR(data->regmap), "regmap initialization failed\n"); 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_info(dev, client->name, data, &max6639_chip_info, NULL); return PTR_ERR_OR_ZERO(hwmon_dev); } static int max6639_suspend(struct device *dev) { struct max6639_data *data = dev_get_drvdata(dev); if (data->reg) regulator_disable(data->reg); return regmap_write_bits(data->regmap, MAX6639_REG_GCONFIG, MAX6639_GCONFIG_STANDBY, MAX6639_GCONFIG_STANDBY); } static int max6639_resume(struct device *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; } } return regmap_write_bits(data->regmap, MAX6639_REG_GCONFIG, MAX6639_GCONFIG_STANDBY, ~MAX6639_GCONFIG_STANDBY); } static const struct i2c_device_id max6639_id[] = { {"max6639"}, { } }; MODULE_DEVICE_TABLE(i2c, max6639_id); static DEFINE_SIMPLE_DEV_PM_OPS(max6639_pm_ops, max6639_suspend, max6639_resume); static const struct of_device_id max6639_of_match[] = { { .compatible = "maxim,max6639", }, { }, }; static struct i2c_driver max6639_driver = { .class = I2C_CLASS_HWMON, .driver = { .name = "max6639", .pm = pm_sleep_ptr(&max6639_pm_ops), .of_match_table = max6639_of_match, }, .probe = 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");