1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * max6639.c - Support for Maxim MAX6639
5 * 2-Channel Temperature Monitor with Dual PWM Fan-Speed Controller
7 * Copyright (C) 2010, 2011 Roland Stigge <stigge@antcom.de>
9 * based on the initial MAX6639 support from semptian.net
10 * by He Changqing <hechangqing@semptian.com>
13 #include <linux/module.h>
14 #include <linux/init.h>
15 #include <linux/slab.h>
16 #include <linux/jiffies.h>
17 #include <linux/i2c.h>
18 #include <linux/hwmon.h>
19 #include <linux/hwmon-sysfs.h>
20 #include <linux/err.h>
21 #include <linux/mutex.h>
22 #include <linux/platform_data/max6639.h>
23 #include <linux/regmap.h>
25 /* Addresses to scan */
26 static const unsigned short normal_i2c[] = { 0x2c, 0x2e, 0x2f, I2C_CLIENT_END };
28 /* The MAX6639 registers, valid channel numbers: 0, 1 */
29 #define MAX6639_REG_TEMP(ch) (0x00 + (ch))
30 #define MAX6639_REG_STATUS 0x02
31 #define MAX6639_REG_OUTPUT_MASK 0x03
32 #define MAX6639_REG_GCONFIG 0x04
33 #define MAX6639_REG_TEMP_EXT(ch) (0x05 + (ch))
34 #define MAX6639_REG_ALERT_LIMIT(ch) (0x08 + (ch))
35 #define MAX6639_REG_OT_LIMIT(ch) (0x0A + (ch))
36 #define MAX6639_REG_THERM_LIMIT(ch) (0x0C + (ch))
37 #define MAX6639_REG_FAN_CONFIG1(ch) (0x10 + (ch) * 4)
38 #define MAX6639_REG_FAN_CONFIG2a(ch) (0x11 + (ch) * 4)
39 #define MAX6639_REG_FAN_CONFIG2b(ch) (0x12 + (ch) * 4)
40 #define MAX6639_REG_FAN_CONFIG3(ch) (0x13 + (ch) * 4)
41 #define MAX6639_REG_FAN_CNT(ch) (0x20 + (ch))
42 #define MAX6639_REG_TARGET_CNT(ch) (0x22 + (ch))
43 #define MAX6639_REG_FAN_PPR(ch) (0x24 + (ch))
44 #define MAX6639_REG_TARGTDUTY(ch) (0x26 + (ch))
45 #define MAX6639_REG_FAN_START_TEMP(ch) (0x28 + (ch))
46 #define MAX6639_REG_DEVID 0x3D
47 #define MAX6639_REG_MANUID 0x3E
48 #define MAX6639_REG_DEVREV 0x3F
51 #define MAX6639_GCONFIG_STANDBY 0x80
52 #define MAX6639_GCONFIG_POR 0x40
53 #define MAX6639_GCONFIG_DISABLE_TIMEOUT 0x20
54 #define MAX6639_GCONFIG_CH2_LOCAL 0x10
55 #define MAX6639_GCONFIG_PWM_FREQ_HI 0x08
57 #define MAX6639_FAN_CONFIG1_PWM 0x80
59 #define MAX6639_FAN_CONFIG3_THERM_FULL_SPEED 0x40
61 #define MAX6639_NUM_CHANNELS 2
63 static const int rpm_ranges[] = { 2000, 4000, 8000, 16000 };
65 #define FAN_FROM_REG(val, rpm_range) ((val) == 0 || (val) == 255 ? \
66 0 : (rpm_ranges[rpm_range] * 30) / (val))
67 #define TEMP_LIMIT_TO_REG(val) clamp_val((val) / 1000, 0, 255)
70 * Client data (each client gets its own)
73 struct regmap *regmap;
75 /* Register values initialized only once */
76 u8 ppr; /* Pulses per rotation 0..3 for 1..4 ppr */
77 u8 rpm_range; /* Index in above rpm_ranges table */
79 /* Optional regulator for FAN supply */
80 struct regulator *reg;
83 static ssize_t temp_input_show(struct device *dev,
84 struct device_attribute *dev_attr, char *buf)
87 struct max6639_data *data = dev_get_drvdata(dev);
88 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
93 * Lock isn't needed as MAX6639_REG_TEMP wpnt change for at least 250ms after reading
94 * MAX6639_REG_TEMP_EXT
96 res = regmap_read(data->regmap, MAX6639_REG_TEMP_EXT(attr->index), &val);
101 res = regmap_read(data->regmap, MAX6639_REG_TEMP(attr->index), &val);
108 return sprintf(buf, "%ld\n", temp);
111 static ssize_t temp_fault_show(struct device *dev,
112 struct device_attribute *dev_attr, char *buf)
114 struct max6639_data *data = dev_get_drvdata(dev);
115 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
119 res = regmap_read(data->regmap, MAX6639_REG_TEMP_EXT(attr->index), &val);
123 return sprintf(buf, "%d\n", val & 1);
126 static ssize_t temp_max_show(struct device *dev,
127 struct device_attribute *dev_attr, char *buf)
129 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
130 struct max6639_data *data = dev_get_drvdata(dev);
134 res = regmap_read(data->regmap, MAX6639_REG_THERM_LIMIT(attr->index), &val);
138 return sprintf(buf, "%d\n", (val * 1000));
141 static ssize_t temp_max_store(struct device *dev,
142 struct device_attribute *dev_attr,
143 const char *buf, size_t count)
145 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
146 struct max6639_data *data = dev_get_drvdata(dev);
150 res = kstrtoul(buf, 10, &val);
154 regmap_write(data->regmap, MAX6639_REG_THERM_LIMIT(attr->index),
155 TEMP_LIMIT_TO_REG(val));
159 static ssize_t temp_crit_show(struct device *dev,
160 struct device_attribute *dev_attr, char *buf)
162 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
163 struct max6639_data *data = dev_get_drvdata(dev);
167 res = regmap_read(data->regmap, MAX6639_REG_ALERT_LIMIT(attr->index), &val);
171 return sprintf(buf, "%d\n", (val * 1000));
174 static ssize_t temp_crit_store(struct device *dev,
175 struct device_attribute *dev_attr,
176 const char *buf, size_t count)
178 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
179 struct max6639_data *data = dev_get_drvdata(dev);
183 res = kstrtoul(buf, 10, &val);
187 regmap_write(data->regmap, MAX6639_REG_ALERT_LIMIT(attr->index),
188 TEMP_LIMIT_TO_REG(val));
192 static ssize_t temp_emergency_show(struct device *dev,
193 struct device_attribute *dev_attr,
196 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
197 struct max6639_data *data = dev_get_drvdata(dev);
201 res = regmap_read(data->regmap, MAX6639_REG_OT_LIMIT(attr->index), &val);
205 return sprintf(buf, "%d\n", (val * 1000));
208 static ssize_t temp_emergency_store(struct device *dev,
209 struct device_attribute *dev_attr,
210 const char *buf, size_t count)
212 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
213 struct max6639_data *data = dev_get_drvdata(dev);
217 res = kstrtoul(buf, 10, &val);
221 regmap_write(data->regmap, MAX6639_REG_OT_LIMIT(attr->index), TEMP_LIMIT_TO_REG(val));
226 static ssize_t pwm_show(struct device *dev, struct device_attribute *dev_attr,
229 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
230 struct max6639_data *data = dev_get_drvdata(dev);
234 res = regmap_read(data->regmap, MAX6639_REG_TARGTDUTY(attr->index), &val);
238 return sprintf(buf, "%d\n", val * 255 / 120);
241 static ssize_t pwm_store(struct device *dev,
242 struct device_attribute *dev_attr, const char *buf,
245 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
246 struct max6639_data *data = dev_get_drvdata(dev);
250 res = kstrtoul(buf, 10, &val);
254 val = clamp_val(val, 0, 255);
256 regmap_write(data->regmap, MAX6639_REG_TARGTDUTY(attr->index), val * 120 / 255);
261 static ssize_t fan_input_show(struct device *dev,
262 struct device_attribute *dev_attr, char *buf)
264 struct max6639_data *data = dev_get_drvdata(dev);
265 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
269 res = regmap_read(data->regmap, MAX6639_REG_FAN_CNT(attr->index), &val);
273 return sprintf(buf, "%d\n", FAN_FROM_REG(val, data->rpm_range));
276 static ssize_t alarm_show(struct device *dev,
277 struct device_attribute *dev_attr, char *buf)
279 struct max6639_data *data = dev_get_drvdata(dev);
280 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
284 res = regmap_read(data->regmap, MAX6639_REG_STATUS, &val);
288 return sprintf(buf, "%d\n", !!(val & (1 << attr->index)));
291 static SENSOR_DEVICE_ATTR_RO(temp1_input, temp_input, 0);
292 static SENSOR_DEVICE_ATTR_RO(temp2_input, temp_input, 1);
293 static SENSOR_DEVICE_ATTR_RO(temp1_fault, temp_fault, 0);
294 static SENSOR_DEVICE_ATTR_RO(temp2_fault, temp_fault, 1);
295 static SENSOR_DEVICE_ATTR_RW(temp1_max, temp_max, 0);
296 static SENSOR_DEVICE_ATTR_RW(temp2_max, temp_max, 1);
297 static SENSOR_DEVICE_ATTR_RW(temp1_crit, temp_crit, 0);
298 static SENSOR_DEVICE_ATTR_RW(temp2_crit, temp_crit, 1);
299 static SENSOR_DEVICE_ATTR_RW(temp1_emergency, temp_emergency, 0);
300 static SENSOR_DEVICE_ATTR_RW(temp2_emergency, temp_emergency, 1);
301 static SENSOR_DEVICE_ATTR_RW(pwm1, pwm, 0);
302 static SENSOR_DEVICE_ATTR_RW(pwm2, pwm, 1);
303 static SENSOR_DEVICE_ATTR_RO(fan1_input, fan_input, 0);
304 static SENSOR_DEVICE_ATTR_RO(fan2_input, fan_input, 1);
305 static SENSOR_DEVICE_ATTR_RO(fan1_fault, alarm, 1);
306 static SENSOR_DEVICE_ATTR_RO(fan2_fault, alarm, 0);
307 static SENSOR_DEVICE_ATTR_RO(temp1_max_alarm, alarm, 3);
308 static SENSOR_DEVICE_ATTR_RO(temp2_max_alarm, alarm, 2);
309 static SENSOR_DEVICE_ATTR_RO(temp1_crit_alarm, alarm, 7);
310 static SENSOR_DEVICE_ATTR_RO(temp2_crit_alarm, alarm, 6);
311 static SENSOR_DEVICE_ATTR_RO(temp1_emergency_alarm, alarm, 5);
312 static SENSOR_DEVICE_ATTR_RO(temp2_emergency_alarm, alarm, 4);
315 static struct attribute *max6639_attrs[] = {
316 &sensor_dev_attr_temp1_input.dev_attr.attr,
317 &sensor_dev_attr_temp2_input.dev_attr.attr,
318 &sensor_dev_attr_temp1_fault.dev_attr.attr,
319 &sensor_dev_attr_temp2_fault.dev_attr.attr,
320 &sensor_dev_attr_temp1_max.dev_attr.attr,
321 &sensor_dev_attr_temp2_max.dev_attr.attr,
322 &sensor_dev_attr_temp1_crit.dev_attr.attr,
323 &sensor_dev_attr_temp2_crit.dev_attr.attr,
324 &sensor_dev_attr_temp1_emergency.dev_attr.attr,
325 &sensor_dev_attr_temp2_emergency.dev_attr.attr,
326 &sensor_dev_attr_pwm1.dev_attr.attr,
327 &sensor_dev_attr_pwm2.dev_attr.attr,
328 &sensor_dev_attr_fan1_input.dev_attr.attr,
329 &sensor_dev_attr_fan2_input.dev_attr.attr,
330 &sensor_dev_attr_fan1_fault.dev_attr.attr,
331 &sensor_dev_attr_fan2_fault.dev_attr.attr,
332 &sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
333 &sensor_dev_attr_temp2_max_alarm.dev_attr.attr,
334 &sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
335 &sensor_dev_attr_temp2_crit_alarm.dev_attr.attr,
336 &sensor_dev_attr_temp1_emergency_alarm.dev_attr.attr,
337 &sensor_dev_attr_temp2_emergency_alarm.dev_attr.attr,
340 ATTRIBUTE_GROUPS(max6639);
343 * returns respective index in rpm_ranges table
344 * 1 by default on invalid range
346 static int rpm_range_to_reg(int range)
350 for (i = 0; i < ARRAY_SIZE(rpm_ranges); i++) {
351 if (rpm_ranges[i] == range)
355 return 1; /* default: 4000 RPM */
358 static int max6639_set_ppr(struct max6639_data *data, u8 channel, u8 ppr)
360 return regmap_write(data->regmap, MAX6639_REG_FAN_PPR(channel), ppr << 6);
363 static int max6639_init_client(struct i2c_client *client,
364 struct max6639_data *data)
366 struct max6639_platform_data *max6639_info =
367 dev_get_platdata(&client->dev);
369 int rpm_range = 1; /* default: 4000 RPM */
372 /* Reset chip to default values, see below for GCONFIG setup */
373 err = regmap_write(data->regmap, MAX6639_REG_GCONFIG, MAX6639_GCONFIG_POR);
377 /* Fans pulse per revolution is 2 by default */
378 if (max6639_info && max6639_info->ppr > 0 &&
379 max6639_info->ppr < 5)
380 ppr = max6639_info->ppr;
386 rpm_range = rpm_range_to_reg(max6639_info->rpm_range);
387 data->rpm_range = rpm_range;
389 for (i = 0; i < MAX6639_NUM_CHANNELS; i++) {
391 /* Set Fan pulse per revolution */
392 err = max6639_set_ppr(data, i, ppr);
396 /* Fans config PWM, RPM */
397 err = regmap_write(data->regmap, MAX6639_REG_FAN_CONFIG1(i),
398 MAX6639_FAN_CONFIG1_PWM | rpm_range);
402 /* Fans PWM polarity high by default */
403 if (max6639_info && max6639_info->pwm_polarity == 0)
404 err = regmap_write(data->regmap, MAX6639_REG_FAN_CONFIG2a(i), 0x00);
406 err = regmap_write(data->regmap, MAX6639_REG_FAN_CONFIG2a(i), 0x02);
411 * /THERM full speed enable,
412 * PWM frequency 25kHz, see also GCONFIG below
414 err = regmap_write(data->regmap, MAX6639_REG_FAN_CONFIG3(i),
415 MAX6639_FAN_CONFIG3_THERM_FULL_SPEED | 0x03);
419 /* Max. temp. 80C/90C/100C */
420 err = regmap_write(data->regmap, MAX6639_REG_THERM_LIMIT(i), 80);
423 err = regmap_write(data->regmap, MAX6639_REG_ALERT_LIMIT(i), 90);
426 err = regmap_write(data->regmap, MAX6639_REG_OT_LIMIT(i), 100);
430 /* PWM 120/120 (i.e. 100%) */
431 err = regmap_write(data->regmap, MAX6639_REG_TARGTDUTY(i), 120);
435 /* Start monitoring */
436 return regmap_write(data->regmap, MAX6639_REG_GCONFIG,
437 MAX6639_GCONFIG_DISABLE_TIMEOUT | MAX6639_GCONFIG_CH2_LOCAL |
438 MAX6639_GCONFIG_PWM_FREQ_HI);
442 /* Return 0 if detection is successful, -ENODEV otherwise */
443 static int max6639_detect(struct i2c_client *client,
444 struct i2c_board_info *info)
446 struct i2c_adapter *adapter = client->adapter;
449 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
452 /* Actual detection via device and manufacturer ID */
453 dev_id = i2c_smbus_read_byte_data(client, MAX6639_REG_DEVID);
454 manu_id = i2c_smbus_read_byte_data(client, MAX6639_REG_MANUID);
455 if (dev_id != 0x58 || manu_id != 0x4D)
458 strscpy(info->type, "max6639", I2C_NAME_SIZE);
463 static void max6639_regulator_disable(void *data)
465 regulator_disable(data);
468 static bool max6639_regmap_is_volatile(struct device *dev, unsigned int reg)
471 case MAX6639_REG_TEMP(0):
472 case MAX6639_REG_TEMP_EXT(0):
473 case MAX6639_REG_TEMP(1):
474 case MAX6639_REG_TEMP_EXT(1):
475 case MAX6639_REG_STATUS:
476 case MAX6639_REG_FAN_CNT(0):
477 case MAX6639_REG_FAN_CNT(1):
478 case MAX6639_REG_TARGTDUTY(0):
479 case MAX6639_REG_TARGTDUTY(1):
486 static const struct regmap_config max6639_regmap_config = {
489 .max_register = MAX6639_REG_DEVREV,
490 .cache_type = REGCACHE_MAPLE,
491 .volatile_reg = max6639_regmap_is_volatile,
494 static int max6639_probe(struct i2c_client *client)
496 struct device *dev = &client->dev;
497 struct max6639_data *data;
498 struct device *hwmon_dev;
501 data = devm_kzalloc(dev, sizeof(struct max6639_data), GFP_KERNEL);
505 data->regmap = devm_regmap_init_i2c(client, &max6639_regmap_config);
506 if (IS_ERR(data->regmap))
507 return dev_err_probe(dev,
508 PTR_ERR(data->regmap),
509 "regmap initialization failed\n");
511 data->reg = devm_regulator_get_optional(dev, "fan");
512 if (IS_ERR(data->reg)) {
513 if (PTR_ERR(data->reg) != -ENODEV)
514 return PTR_ERR(data->reg);
519 err = regulator_enable(data->reg);
521 dev_err(dev, "Failed to enable fan supply: %d\n", err);
524 err = devm_add_action_or_reset(dev, max6639_regulator_disable,
527 dev_err(dev, "Failed to register action: %d\n", err);
532 /* Initialize the max6639 chip */
533 err = max6639_init_client(client, data);
537 hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
540 return PTR_ERR_OR_ZERO(hwmon_dev);
543 static int max6639_suspend(struct device *dev)
545 struct max6639_data *data = dev_get_drvdata(dev);
548 regulator_disable(data->reg);
550 return regmap_write_bits(data->regmap, MAX6639_REG_GCONFIG, MAX6639_GCONFIG_STANDBY,
551 MAX6639_GCONFIG_STANDBY);
554 static int max6639_resume(struct device *dev)
556 struct max6639_data *data = dev_get_drvdata(dev);
560 ret = regulator_enable(data->reg);
562 dev_err(dev, "Failed to enable fan supply: %d\n", ret);
567 return regmap_write_bits(data->regmap, MAX6639_REG_GCONFIG, MAX6639_GCONFIG_STANDBY,
568 ~MAX6639_GCONFIG_STANDBY);
571 static const struct i2c_device_id max6639_id[] = {
576 MODULE_DEVICE_TABLE(i2c, max6639_id);
578 static DEFINE_SIMPLE_DEV_PM_OPS(max6639_pm_ops, max6639_suspend, max6639_resume);
580 static const struct of_device_id max6639_of_match[] = {
581 { .compatible = "maxim,max6639", },
585 static struct i2c_driver max6639_driver = {
586 .class = I2C_CLASS_HWMON,
589 .pm = pm_sleep_ptr(&max6639_pm_ops),
590 .of_match_table = max6639_of_match,
592 .probe = max6639_probe,
593 .id_table = max6639_id,
594 .detect = max6639_detect,
595 .address_list = normal_i2c,
598 module_i2c_driver(max6639_driver);
600 MODULE_AUTHOR("Roland Stigge <stigge@antcom.de>");
601 MODULE_DESCRIPTION("max6639 driver");
602 MODULE_LICENSE("GPL");