2 * max6639.c - Support for Maxim MAX6639
4 * 2-Channel Temperature Monitor with Dual PWM Fan-Speed Controller
6 * Copyright (C) 2010, 2011 Roland Stigge <stigge@antcom.de>
8 * based on the initial MAX6639 support from semptian.net
9 * by He Changqing <hechangqing@semptian.com>
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation; either version 2 of the License, or
14 * (at your option) any later version.
16 * This program is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 * GNU General Public License for more details.
21 * You should have received a copy of the GNU General Public License
22 * along with this program; if not, write to the Free Software
23 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
26 #include <linux/module.h>
27 #include <linux/init.h>
28 #include <linux/slab.h>
29 #include <linux/jiffies.h>
30 #include <linux/i2c.h>
31 #include <linux/hwmon.h>
32 #include <linux/hwmon-sysfs.h>
33 #include <linux/err.h>
34 #include <linux/mutex.h>
35 #include <linux/i2c/max6639.h>
37 /* Addresses to scan */
38 static const unsigned short normal_i2c
[] = { 0x2c, 0x2e, 0x2f, I2C_CLIENT_END
};
40 /* The MAX6639 registers, valid channel numbers: 0, 1 */
41 #define MAX6639_REG_TEMP(ch) (0x00 + (ch))
42 #define MAX6639_REG_STATUS 0x02
43 #define MAX6639_REG_OUTPUT_MASK 0x03
44 #define MAX6639_REG_GCONFIG 0x04
45 #define MAX6639_REG_TEMP_EXT(ch) (0x05 + (ch))
46 #define MAX6639_REG_ALERT_LIMIT(ch) (0x08 + (ch))
47 #define MAX6639_REG_OT_LIMIT(ch) (0x0A + (ch))
48 #define MAX6639_REG_THERM_LIMIT(ch) (0x0C + (ch))
49 #define MAX6639_REG_FAN_CONFIG1(ch) (0x10 + (ch) * 4)
50 #define MAX6639_REG_FAN_CONFIG2a(ch) (0x11 + (ch) * 4)
51 #define MAX6639_REG_FAN_CONFIG2b(ch) (0x12 + (ch) * 4)
52 #define MAX6639_REG_FAN_CONFIG3(ch) (0x13 + (ch) * 4)
53 #define MAX6639_REG_FAN_CNT(ch) (0x20 + (ch))
54 #define MAX6639_REG_TARGET_CNT(ch) (0x22 + (ch))
55 #define MAX6639_REG_FAN_PPR(ch) (0x24 + (ch))
56 #define MAX6639_REG_TARGTDUTY(ch) (0x26 + (ch))
57 #define MAX6639_REG_FAN_START_TEMP(ch) (0x28 + (ch))
58 #define MAX6639_REG_DEVID 0x3D
59 #define MAX6639_REG_MANUID 0x3E
60 #define MAX6639_REG_DEVREV 0x3F
63 #define MAX6639_GCONFIG_STANDBY 0x80
64 #define MAX6639_GCONFIG_POR 0x40
65 #define MAX6639_GCONFIG_DISABLE_TIMEOUT 0x20
66 #define MAX6639_GCONFIG_CH2_LOCAL 0x10
67 #define MAX6639_GCONFIG_PWM_FREQ_HI 0x08
69 #define MAX6639_FAN_CONFIG1_PWM 0x80
71 #define MAX6639_FAN_CONFIG3_THERM_FULL_SPEED 0x40
73 static const int rpm_ranges
[] = { 2000, 4000, 8000, 16000 };
75 #define FAN_FROM_REG(val, rpm_range) ((val) == 0 || (val) == 255 ? \
76 0 : (rpm_ranges[rpm_range] * 30) / (val))
77 #define TEMP_LIMIT_TO_REG(val) clamp_val((val) / 1000, 0, 255)
80 * Client data (each client gets its own)
83 struct i2c_client
*client
;
84 struct mutex update_lock
;
85 char valid
; /* !=0 if following fields are valid */
86 unsigned long last_updated
; /* In jiffies */
88 /* Register values sampled regularly */
89 u16 temp
[2]; /* Temperature, in 1/8 C, 0..255 C */
90 bool temp_fault
[2]; /* Detected temperature diode failure */
91 u8 fan
[2]; /* Register value: TACH count for fans >=30 */
92 u8 status
; /* Detected channel alarms and fan failures */
94 /* Register values only written to */
95 u8 pwm
[2]; /* Register value: Duty cycle 0..120 */
96 u8 temp_therm
[2]; /* THERM Temperature, 0..255 C (->_max) */
97 u8 temp_alert
[2]; /* ALERT Temperature, 0..255 C (->_crit) */
98 u8 temp_ot
[2]; /* OT Temperature, 0..255 C (->_emergency) */
100 /* Register values initialized only once */
101 u8 ppr
; /* Pulses per rotation 0..3 for 1..4 ppr */
102 u8 rpm_range
; /* Index in above rpm_ranges table */
105 static struct max6639_data
*max6639_update_device(struct device
*dev
)
107 struct max6639_data
*data
= dev_get_drvdata(dev
);
108 struct i2c_client
*client
= data
->client
;
109 struct max6639_data
*ret
= data
;
113 mutex_lock(&data
->update_lock
);
115 if (time_after(jiffies
, data
->last_updated
+ 2 * HZ
) || !data
->valid
) {
118 dev_dbg(&client
->dev
, "Starting max6639 update\n");
120 status_reg
= i2c_smbus_read_byte_data(client
,
122 if (status_reg
< 0) {
123 ret
= ERR_PTR(status_reg
);
127 data
->status
= status_reg
;
129 for (i
= 0; i
< 2; i
++) {
130 res
= i2c_smbus_read_byte_data(client
,
131 MAX6639_REG_FAN_CNT(i
));
138 res
= i2c_smbus_read_byte_data(client
,
139 MAX6639_REG_TEMP_EXT(i
));
144 data
->temp
[i
] = res
>> 5;
145 data
->temp_fault
[i
] = res
& 0x01;
147 res
= i2c_smbus_read_byte_data(client
,
148 MAX6639_REG_TEMP(i
));
153 data
->temp
[i
] |= res
<< 3;
156 data
->last_updated
= jiffies
;
160 mutex_unlock(&data
->update_lock
);
165 static ssize_t
show_temp_input(struct device
*dev
,
166 struct device_attribute
*dev_attr
, char *buf
)
169 struct max6639_data
*data
= max6639_update_device(dev
);
170 struct sensor_device_attribute
*attr
= to_sensor_dev_attr(dev_attr
);
173 return PTR_ERR(data
);
175 temp
= data
->temp
[attr
->index
] * 125;
176 return sprintf(buf
, "%ld\n", temp
);
179 static ssize_t
show_temp_fault(struct device
*dev
,
180 struct device_attribute
*dev_attr
, char *buf
)
182 struct max6639_data
*data
= max6639_update_device(dev
);
183 struct sensor_device_attribute
*attr
= to_sensor_dev_attr(dev_attr
);
186 return PTR_ERR(data
);
188 return sprintf(buf
, "%d\n", data
->temp_fault
[attr
->index
]);
191 static ssize_t
show_temp_max(struct device
*dev
,
192 struct device_attribute
*dev_attr
, char *buf
)
194 struct sensor_device_attribute
*attr
= to_sensor_dev_attr(dev_attr
);
195 struct max6639_data
*data
= dev_get_drvdata(dev
);
197 return sprintf(buf
, "%d\n", (data
->temp_therm
[attr
->index
] * 1000));
200 static ssize_t
set_temp_max(struct device
*dev
,
201 struct device_attribute
*dev_attr
,
202 const char *buf
, size_t count
)
204 struct sensor_device_attribute
*attr
= to_sensor_dev_attr(dev_attr
);
205 struct max6639_data
*data
= dev_get_drvdata(dev
);
206 struct i2c_client
*client
= data
->client
;
210 res
= kstrtoul(buf
, 10, &val
);
214 mutex_lock(&data
->update_lock
);
215 data
->temp_therm
[attr
->index
] = TEMP_LIMIT_TO_REG(val
);
216 i2c_smbus_write_byte_data(client
,
217 MAX6639_REG_THERM_LIMIT(attr
->index
),
218 data
->temp_therm
[attr
->index
]);
219 mutex_unlock(&data
->update_lock
);
223 static ssize_t
show_temp_crit(struct device
*dev
,
224 struct device_attribute
*dev_attr
, char *buf
)
226 struct sensor_device_attribute
*attr
= to_sensor_dev_attr(dev_attr
);
227 struct max6639_data
*data
= dev_get_drvdata(dev
);
229 return sprintf(buf
, "%d\n", (data
->temp_alert
[attr
->index
] * 1000));
232 static ssize_t
set_temp_crit(struct device
*dev
,
233 struct device_attribute
*dev_attr
,
234 const char *buf
, size_t count
)
236 struct sensor_device_attribute
*attr
= to_sensor_dev_attr(dev_attr
);
237 struct max6639_data
*data
= dev_get_drvdata(dev
);
238 struct i2c_client
*client
= data
->client
;
242 res
= kstrtoul(buf
, 10, &val
);
246 mutex_lock(&data
->update_lock
);
247 data
->temp_alert
[attr
->index
] = TEMP_LIMIT_TO_REG(val
);
248 i2c_smbus_write_byte_data(client
,
249 MAX6639_REG_ALERT_LIMIT(attr
->index
),
250 data
->temp_alert
[attr
->index
]);
251 mutex_unlock(&data
->update_lock
);
255 static ssize_t
show_temp_emergency(struct device
*dev
,
256 struct device_attribute
*dev_attr
,
259 struct sensor_device_attribute
*attr
= to_sensor_dev_attr(dev_attr
);
260 struct max6639_data
*data
= dev_get_drvdata(dev
);
262 return sprintf(buf
, "%d\n", (data
->temp_ot
[attr
->index
] * 1000));
265 static ssize_t
set_temp_emergency(struct device
*dev
,
266 struct device_attribute
*dev_attr
,
267 const char *buf
, size_t count
)
269 struct sensor_device_attribute
*attr
= to_sensor_dev_attr(dev_attr
);
270 struct max6639_data
*data
= dev_get_drvdata(dev
);
271 struct i2c_client
*client
= data
->client
;
275 res
= kstrtoul(buf
, 10, &val
);
279 mutex_lock(&data
->update_lock
);
280 data
->temp_ot
[attr
->index
] = TEMP_LIMIT_TO_REG(val
);
281 i2c_smbus_write_byte_data(client
,
282 MAX6639_REG_OT_LIMIT(attr
->index
),
283 data
->temp_ot
[attr
->index
]);
284 mutex_unlock(&data
->update_lock
);
288 static ssize_t
show_pwm(struct device
*dev
,
289 struct device_attribute
*dev_attr
, char *buf
)
291 struct sensor_device_attribute
*attr
= to_sensor_dev_attr(dev_attr
);
292 struct max6639_data
*data
= dev_get_drvdata(dev
);
294 return sprintf(buf
, "%d\n", data
->pwm
[attr
->index
] * 255 / 120);
297 static ssize_t
set_pwm(struct device
*dev
,
298 struct device_attribute
*dev_attr
,
299 const char *buf
, size_t count
)
301 struct sensor_device_attribute
*attr
= to_sensor_dev_attr(dev_attr
);
302 struct max6639_data
*data
= dev_get_drvdata(dev
);
303 struct i2c_client
*client
= data
->client
;
307 res
= kstrtoul(buf
, 10, &val
);
311 val
= clamp_val(val
, 0, 255);
313 mutex_lock(&data
->update_lock
);
314 data
->pwm
[attr
->index
] = (u8
)(val
* 120 / 255);
315 i2c_smbus_write_byte_data(client
,
316 MAX6639_REG_TARGTDUTY(attr
->index
),
317 data
->pwm
[attr
->index
]);
318 mutex_unlock(&data
->update_lock
);
322 static ssize_t
show_fan_input(struct device
*dev
,
323 struct device_attribute
*dev_attr
, char *buf
)
325 struct max6639_data
*data
= max6639_update_device(dev
);
326 struct sensor_device_attribute
*attr
= to_sensor_dev_attr(dev_attr
);
329 return PTR_ERR(data
);
331 return sprintf(buf
, "%d\n", FAN_FROM_REG(data
->fan
[attr
->index
],
335 static ssize_t
show_alarm(struct device
*dev
,
336 struct device_attribute
*dev_attr
, char *buf
)
338 struct max6639_data
*data
= max6639_update_device(dev
);
339 struct sensor_device_attribute
*attr
= to_sensor_dev_attr(dev_attr
);
342 return PTR_ERR(data
);
344 return sprintf(buf
, "%d\n", !!(data
->status
& (1 << attr
->index
)));
347 static SENSOR_DEVICE_ATTR(temp1_input
, S_IRUGO
, show_temp_input
, NULL
, 0);
348 static SENSOR_DEVICE_ATTR(temp2_input
, S_IRUGO
, show_temp_input
, NULL
, 1);
349 static SENSOR_DEVICE_ATTR(temp1_fault
, S_IRUGO
, show_temp_fault
, NULL
, 0);
350 static SENSOR_DEVICE_ATTR(temp2_fault
, S_IRUGO
, show_temp_fault
, NULL
, 1);
351 static SENSOR_DEVICE_ATTR(temp1_max
, S_IWUSR
| S_IRUGO
, show_temp_max
,
353 static SENSOR_DEVICE_ATTR(temp2_max
, S_IWUSR
| S_IRUGO
, show_temp_max
,
355 static SENSOR_DEVICE_ATTR(temp1_crit
, S_IWUSR
| S_IRUGO
, show_temp_crit
,
357 static SENSOR_DEVICE_ATTR(temp2_crit
, S_IWUSR
| S_IRUGO
, show_temp_crit
,
359 static SENSOR_DEVICE_ATTR(temp1_emergency
, S_IWUSR
| S_IRUGO
,
360 show_temp_emergency
, set_temp_emergency
, 0);
361 static SENSOR_DEVICE_ATTR(temp2_emergency
, S_IWUSR
| S_IRUGO
,
362 show_temp_emergency
, set_temp_emergency
, 1);
363 static SENSOR_DEVICE_ATTR(pwm1
, S_IWUSR
| S_IRUGO
, show_pwm
, set_pwm
, 0);
364 static SENSOR_DEVICE_ATTR(pwm2
, S_IWUSR
| S_IRUGO
, show_pwm
, set_pwm
, 1);
365 static SENSOR_DEVICE_ATTR(fan1_input
, S_IRUGO
, show_fan_input
, NULL
, 0);
366 static SENSOR_DEVICE_ATTR(fan2_input
, S_IRUGO
, show_fan_input
, NULL
, 1);
367 static SENSOR_DEVICE_ATTR(fan1_fault
, S_IRUGO
, show_alarm
, NULL
, 1);
368 static SENSOR_DEVICE_ATTR(fan2_fault
, S_IRUGO
, show_alarm
, NULL
, 0);
369 static SENSOR_DEVICE_ATTR(temp1_max_alarm
, S_IRUGO
, show_alarm
, NULL
, 3);
370 static SENSOR_DEVICE_ATTR(temp2_max_alarm
, S_IRUGO
, show_alarm
, NULL
, 2);
371 static SENSOR_DEVICE_ATTR(temp1_crit_alarm
, S_IRUGO
, show_alarm
, NULL
, 7);
372 static SENSOR_DEVICE_ATTR(temp2_crit_alarm
, S_IRUGO
, show_alarm
, NULL
, 6);
373 static SENSOR_DEVICE_ATTR(temp1_emergency_alarm
, S_IRUGO
, show_alarm
, NULL
, 5);
374 static SENSOR_DEVICE_ATTR(temp2_emergency_alarm
, S_IRUGO
, show_alarm
, NULL
, 4);
377 static struct attribute
*max6639_attrs
[] = {
378 &sensor_dev_attr_temp1_input
.dev_attr
.attr
,
379 &sensor_dev_attr_temp2_input
.dev_attr
.attr
,
380 &sensor_dev_attr_temp1_fault
.dev_attr
.attr
,
381 &sensor_dev_attr_temp2_fault
.dev_attr
.attr
,
382 &sensor_dev_attr_temp1_max
.dev_attr
.attr
,
383 &sensor_dev_attr_temp2_max
.dev_attr
.attr
,
384 &sensor_dev_attr_temp1_crit
.dev_attr
.attr
,
385 &sensor_dev_attr_temp2_crit
.dev_attr
.attr
,
386 &sensor_dev_attr_temp1_emergency
.dev_attr
.attr
,
387 &sensor_dev_attr_temp2_emergency
.dev_attr
.attr
,
388 &sensor_dev_attr_pwm1
.dev_attr
.attr
,
389 &sensor_dev_attr_pwm2
.dev_attr
.attr
,
390 &sensor_dev_attr_fan1_input
.dev_attr
.attr
,
391 &sensor_dev_attr_fan2_input
.dev_attr
.attr
,
392 &sensor_dev_attr_fan1_fault
.dev_attr
.attr
,
393 &sensor_dev_attr_fan2_fault
.dev_attr
.attr
,
394 &sensor_dev_attr_temp1_max_alarm
.dev_attr
.attr
,
395 &sensor_dev_attr_temp2_max_alarm
.dev_attr
.attr
,
396 &sensor_dev_attr_temp1_crit_alarm
.dev_attr
.attr
,
397 &sensor_dev_attr_temp2_crit_alarm
.dev_attr
.attr
,
398 &sensor_dev_attr_temp1_emergency_alarm
.dev_attr
.attr
,
399 &sensor_dev_attr_temp2_emergency_alarm
.dev_attr
.attr
,
402 ATTRIBUTE_GROUPS(max6639
);
405 * returns respective index in rpm_ranges table
406 * 1 by default on invalid range
408 static int rpm_range_to_reg(int range
)
412 for (i
= 0; i
< ARRAY_SIZE(rpm_ranges
); i
++) {
413 if (rpm_ranges
[i
] == range
)
417 return 1; /* default: 4000 RPM */
420 static int max6639_init_client(struct i2c_client
*client
,
421 struct max6639_data
*data
)
423 struct max6639_platform_data
*max6639_info
=
424 dev_get_platdata(&client
->dev
);
426 int rpm_range
= 1; /* default: 4000 RPM */
429 /* Reset chip to default values, see below for GCONFIG setup */
430 err
= i2c_smbus_write_byte_data(client
, MAX6639_REG_GCONFIG
,
431 MAX6639_GCONFIG_POR
);
435 /* Fans pulse per revolution is 2 by default */
436 if (max6639_info
&& max6639_info
->ppr
> 0 &&
437 max6639_info
->ppr
< 5)
438 data
->ppr
= max6639_info
->ppr
;
444 rpm_range
= rpm_range_to_reg(max6639_info
->rpm_range
);
445 data
->rpm_range
= rpm_range
;
447 for (i
= 0; i
< 2; i
++) {
449 /* Set Fan pulse per revolution */
450 err
= i2c_smbus_write_byte_data(client
,
451 MAX6639_REG_FAN_PPR(i
),
456 /* Fans config PWM, RPM */
457 err
= i2c_smbus_write_byte_data(client
,
458 MAX6639_REG_FAN_CONFIG1(i
),
459 MAX6639_FAN_CONFIG1_PWM
| rpm_range
);
463 /* Fans PWM polarity high by default */
464 if (max6639_info
&& max6639_info
->pwm_polarity
== 0)
465 err
= i2c_smbus_write_byte_data(client
,
466 MAX6639_REG_FAN_CONFIG2a(i
), 0x00);
468 err
= i2c_smbus_write_byte_data(client
,
469 MAX6639_REG_FAN_CONFIG2a(i
), 0x02);
474 * /THERM full speed enable,
475 * PWM frequency 25kHz, see also GCONFIG below
477 err
= i2c_smbus_write_byte_data(client
,
478 MAX6639_REG_FAN_CONFIG3(i
),
479 MAX6639_FAN_CONFIG3_THERM_FULL_SPEED
| 0x03);
483 /* Max. temp. 80C/90C/100C */
484 data
->temp_therm
[i
] = 80;
485 data
->temp_alert
[i
] = 90;
486 data
->temp_ot
[i
] = 100;
487 err
= i2c_smbus_write_byte_data(client
,
488 MAX6639_REG_THERM_LIMIT(i
),
489 data
->temp_therm
[i
]);
492 err
= i2c_smbus_write_byte_data(client
,
493 MAX6639_REG_ALERT_LIMIT(i
),
494 data
->temp_alert
[i
]);
497 err
= i2c_smbus_write_byte_data(client
,
498 MAX6639_REG_OT_LIMIT(i
), data
->temp_ot
[i
]);
502 /* PWM 120/120 (i.e. 100%) */
504 err
= i2c_smbus_write_byte_data(client
,
505 MAX6639_REG_TARGTDUTY(i
), data
->pwm
[i
]);
509 /* Start monitoring */
510 err
= i2c_smbus_write_byte_data(client
, MAX6639_REG_GCONFIG
,
511 MAX6639_GCONFIG_DISABLE_TIMEOUT
| MAX6639_GCONFIG_CH2_LOCAL
|
512 MAX6639_GCONFIG_PWM_FREQ_HI
);
517 /* Return 0 if detection is successful, -ENODEV otherwise */
518 static int max6639_detect(struct i2c_client
*client
,
519 struct i2c_board_info
*info
)
521 struct i2c_adapter
*adapter
= client
->adapter
;
524 if (!i2c_check_functionality(adapter
, I2C_FUNC_SMBUS_BYTE_DATA
))
527 /* Actual detection via device and manufacturer ID */
528 dev_id
= i2c_smbus_read_byte_data(client
, MAX6639_REG_DEVID
);
529 manu_id
= i2c_smbus_read_byte_data(client
, MAX6639_REG_MANUID
);
530 if (dev_id
!= 0x58 || manu_id
!= 0x4D)
533 strlcpy(info
->type
, "max6639", I2C_NAME_SIZE
);
538 static int max6639_probe(struct i2c_client
*client
,
539 const struct i2c_device_id
*id
)
541 struct device
*dev
= &client
->dev
;
542 struct max6639_data
*data
;
543 struct device
*hwmon_dev
;
546 data
= devm_kzalloc(dev
, sizeof(struct max6639_data
), GFP_KERNEL
);
550 data
->client
= client
;
551 mutex_init(&data
->update_lock
);
553 /* Initialize the max6639 chip */
554 err
= max6639_init_client(client
, data
);
558 hwmon_dev
= devm_hwmon_device_register_with_groups(dev
, client
->name
,
561 return PTR_ERR_OR_ZERO(hwmon_dev
);
564 #ifdef CONFIG_PM_SLEEP
565 static int max6639_suspend(struct device
*dev
)
567 struct i2c_client
*client
= to_i2c_client(dev
);
568 int data
= i2c_smbus_read_byte_data(client
, MAX6639_REG_GCONFIG
);
572 return i2c_smbus_write_byte_data(client
,
573 MAX6639_REG_GCONFIG
, data
| MAX6639_GCONFIG_STANDBY
);
576 static int max6639_resume(struct device
*dev
)
578 struct i2c_client
*client
= to_i2c_client(dev
);
579 int data
= i2c_smbus_read_byte_data(client
, MAX6639_REG_GCONFIG
);
583 return i2c_smbus_write_byte_data(client
,
584 MAX6639_REG_GCONFIG
, data
& ~MAX6639_GCONFIG_STANDBY
);
586 #endif /* CONFIG_PM_SLEEP */
588 static const struct i2c_device_id max6639_id
[] = {
593 MODULE_DEVICE_TABLE(i2c
, max6639_id
);
595 static SIMPLE_DEV_PM_OPS(max6639_pm_ops
, max6639_suspend
, max6639_resume
);
597 static struct i2c_driver max6639_driver
= {
598 .class = I2C_CLASS_HWMON
,
601 .pm
= &max6639_pm_ops
,
603 .probe
= max6639_probe
,
604 .id_table
= max6639_id
,
605 .detect
= max6639_detect
,
606 .address_list
= normal_i2c
,
609 module_i2c_driver(max6639_driver
);
611 MODULE_AUTHOR("Roland Stigge <stigge@antcom.de>");
612 MODULE_DESCRIPTION("max6639 driver");
613 MODULE_LICENSE("GPL");