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1/*
2 * max6639.c - Support for Maxim MAX6639
3 *
4 * 2-Channel Temperature Monitor with Dual PWM Fan-Speed Controller
5 *
6 * Copyright (C) 2010, 2011 Roland Stigge <stigge@antcom.de>
7 *
8 * based on the initial MAX6639 support from semptian.net
9 * by He Changqing <hechangqing@semptian.com>
10 *
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.
15 *
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.
20 *
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.
24 */
25
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>
36
37/* Addresses to scan */
38static unsigned short normal_i2c[] = { 0x2c, 0x2e, 0x2f, I2C_CLIENT_END };
39
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
61
62/* Register bits */
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
68
69#define MAX6639_FAN_CONFIG1_PWM 0x80
70
71#define MAX6639_FAN_CONFIG3_THERM_FULL_SPEED 0x40
72
73static const int rpm_ranges[] = { 2000, 4000, 8000, 16000 };
74
75#define FAN_FROM_REG(val, div, rpm_range) ((val) == 0 ? -1 : \
76 (val) == 255 ? 0 : (rpm_ranges[rpm_range] * 30) / ((div + 1) * (val)))
77#define TEMP_LIMIT_TO_REG(val) SENSORS_LIMIT((val) / 1000, 0, 255)
78
79/*
80 * Client data (each client gets its own)
81 */
82struct max6639_data {
83 struct device *hwmon_dev;
84 struct mutex update_lock;
85 char valid; /* !=0 if following fields are valid */
86 unsigned long last_updated; /* In jiffies */
87
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 */
93
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) */
99
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 */
103};
104
105static struct max6639_data *max6639_update_device(struct device *dev)
106{
107 struct i2c_client *client = to_i2c_client(dev);
108 struct max6639_data *data = i2c_get_clientdata(client);
109 struct max6639_data *ret = data;
110 int i;
111 int status_reg;
112
113 mutex_lock(&data->update_lock);
114
115 if (time_after(jiffies, data->last_updated + 2 * HZ) || !data->valid) {
116 int res;
117
118 dev_dbg(&client->dev, "Starting max6639 update\n");
119
120 status_reg = i2c_smbus_read_byte_data(client,
121 MAX6639_REG_STATUS);
122 if (status_reg < 0) {
123 ret = ERR_PTR(status_reg);
124 goto abort;
125 }
126
127 data->status = status_reg;
128
129 for (i = 0; i < 2; i++) {
130 res = i2c_smbus_read_byte_data(client,
131 MAX6639_REG_FAN_CNT(i));
132 if (res < 0) {
133 ret = ERR_PTR(res);
134 goto abort;
135 }
136 data->fan[i] = res;
137
138 res = i2c_smbus_read_byte_data(client,
139 MAX6639_REG_TEMP_EXT(i));
140 if (res < 0) {
141 ret = ERR_PTR(res);
142 goto abort;
143 }
144 data->temp[i] = res >> 5;
145 data->temp_fault[i] = res & 0x01;
146
147 res = i2c_smbus_read_byte_data(client,
148 MAX6639_REG_TEMP(i));
149 if (res < 0) {
150 ret = ERR_PTR(res);
151 goto abort;
152 }
153 data->temp[i] |= res << 3;
154 }
155
156 data->last_updated = jiffies;
157 data->valid = 1;
158 }
159abort:
160 mutex_unlock(&data->update_lock);
161
162 return ret;
163}
164
165static ssize_t show_temp_input(struct device *dev,
166 struct device_attribute *dev_attr, char *buf)
167{
168 long temp;
169 struct max6639_data *data = max6639_update_device(dev);
170 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
171
172 if (IS_ERR(data))
173 return PTR_ERR(data);
174
175 temp = data->temp[attr->index] * 125;
176 return sprintf(buf, "%ld\n", temp);
177}
178
179static ssize_t show_temp_fault(struct device *dev,
180 struct device_attribute *dev_attr, char *buf)
181{
182 struct max6639_data *data = max6639_update_device(dev);
183 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
184
185 if (IS_ERR(data))
186 return PTR_ERR(data);
187
188 return sprintf(buf, "%d\n", data->temp_fault[attr->index]);
189}
190
191static ssize_t show_temp_max(struct device *dev,
192 struct device_attribute *dev_attr, char *buf)
193{
194 struct i2c_client *client = to_i2c_client(dev);
195 struct max6639_data *data = i2c_get_clientdata(client);
196 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
197
198 return sprintf(buf, "%d\n", (data->temp_therm[attr->index] * 1000));
199}
200
201static ssize_t set_temp_max(struct device *dev,
202 struct device_attribute *dev_attr,
203 const char *buf, size_t count)
204{
205 struct i2c_client *client = to_i2c_client(dev);
206 struct max6639_data *data = i2c_get_clientdata(client);
207 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
208 unsigned long val;
209 int res;
210
211 res = strict_strtoul(buf, 10, &val);
212 if (res)
213 return res;
214
215 mutex_lock(&data->update_lock);
216 data->temp_therm[attr->index] = TEMP_LIMIT_TO_REG(val);
217 i2c_smbus_write_byte_data(client,
218 MAX6639_REG_THERM_LIMIT(attr->index),
219 data->temp_therm[attr->index]);
220 mutex_unlock(&data->update_lock);
221 return count;
222}
223
224static ssize_t show_temp_crit(struct device *dev,
225 struct device_attribute *dev_attr, char *buf)
226{
227 struct i2c_client *client = to_i2c_client(dev);
228 struct max6639_data *data = i2c_get_clientdata(client);
229 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
230
231 return sprintf(buf, "%d\n", (data->temp_alert[attr->index] * 1000));
232}
233
234static ssize_t set_temp_crit(struct device *dev,
235 struct device_attribute *dev_attr,
236 const char *buf, size_t count)
237{
238 struct i2c_client *client = to_i2c_client(dev);
239 struct max6639_data *data = i2c_get_clientdata(client);
240 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
241 unsigned long val;
242 int res;
243
244 res = strict_strtoul(buf, 10, &val);
245 if (res)
246 return res;
247
248 mutex_lock(&data->update_lock);
249 data->temp_alert[attr->index] = TEMP_LIMIT_TO_REG(val);
250 i2c_smbus_write_byte_data(client,
251 MAX6639_REG_ALERT_LIMIT(attr->index),
252 data->temp_alert[attr->index]);
253 mutex_unlock(&data->update_lock);
254 return count;
255}
256
257static ssize_t show_temp_emergency(struct device *dev,
258 struct device_attribute *dev_attr,
259 char *buf)
260{
261 struct i2c_client *client = to_i2c_client(dev);
262 struct max6639_data *data = i2c_get_clientdata(client);
263 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
264
265 return sprintf(buf, "%d\n", (data->temp_ot[attr->index] * 1000));
266}
267
268static ssize_t set_temp_emergency(struct device *dev,
269 struct device_attribute *dev_attr,
270 const char *buf, size_t count)
271{
272 struct i2c_client *client = to_i2c_client(dev);
273 struct max6639_data *data = i2c_get_clientdata(client);
274 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
275 unsigned long val;
276 int res;
277
278 res = strict_strtoul(buf, 10, &val);
279 if (res)
280 return res;
281
282 mutex_lock(&data->update_lock);
283 data->temp_ot[attr->index] = TEMP_LIMIT_TO_REG(val);
284 i2c_smbus_write_byte_data(client,
285 MAX6639_REG_OT_LIMIT(attr->index),
286 data->temp_ot[attr->index]);
287 mutex_unlock(&data->update_lock);
288 return count;
289}
290
291static ssize_t show_pwm(struct device *dev,
292 struct device_attribute *dev_attr, char *buf)
293{
294 struct i2c_client *client = to_i2c_client(dev);
295 struct max6639_data *data = i2c_get_clientdata(client);
296 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
297
298 return sprintf(buf, "%d\n", data->pwm[attr->index] * 255 / 120);
299}
300
301static ssize_t set_pwm(struct device *dev,
302 struct device_attribute *dev_attr,
303 const char *buf, size_t count)
304{
305 struct i2c_client *client = to_i2c_client(dev);
306 struct max6639_data *data = i2c_get_clientdata(client);
307 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
308 unsigned long val;
309 int res;
310
311 res = strict_strtoul(buf, 10, &val);
312 if (res)
313 return res;
314
315 val = SENSORS_LIMIT(val, 0, 255);
316
317 mutex_lock(&data->update_lock);
318 data->pwm[attr->index] = (u8)(val * 120 / 255);
319 i2c_smbus_write_byte_data(client,
320 MAX6639_REG_TARGTDUTY(attr->index),
321 data->pwm[attr->index]);
322 mutex_unlock(&data->update_lock);
323 return count;
324}
325
326static ssize_t show_fan_input(struct device *dev,
327 struct device_attribute *dev_attr, char *buf)
328{
329 struct max6639_data *data = max6639_update_device(dev);
330 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
331
332 if (IS_ERR(data))
333 return PTR_ERR(data);
334
335 return sprintf(buf, "%d\n", FAN_FROM_REG(data->fan[attr->index],
336 data->ppr, data->rpm_range));
337}
338
339static ssize_t show_alarm(struct device *dev,
340 struct device_attribute *dev_attr, char *buf)
341{
342 struct max6639_data *data = max6639_update_device(dev);
343 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
344
345 if (IS_ERR(data))
346 return PTR_ERR(data);
347
348 return sprintf(buf, "%d\n", !!(data->status & (1 << attr->index)));
349}
350
351static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp_input, NULL, 0);
352static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_temp_input, NULL, 1);
353static SENSOR_DEVICE_ATTR(temp1_fault, S_IRUGO, show_temp_fault, NULL, 0);
354static SENSOR_DEVICE_ATTR(temp2_fault, S_IRUGO, show_temp_fault, NULL, 1);
355static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, show_temp_max,
356 set_temp_max, 0);
357static SENSOR_DEVICE_ATTR(temp2_max, S_IWUSR | S_IRUGO, show_temp_max,
358 set_temp_max, 1);
359static SENSOR_DEVICE_ATTR(temp1_crit, S_IWUSR | S_IRUGO, show_temp_crit,
360 set_temp_crit, 0);
361static SENSOR_DEVICE_ATTR(temp2_crit, S_IWUSR | S_IRUGO, show_temp_crit,
362 set_temp_crit, 1);
363static SENSOR_DEVICE_ATTR(temp1_emergency, S_IWUSR | S_IRUGO,
364 show_temp_emergency, set_temp_emergency, 0);
365static SENSOR_DEVICE_ATTR(temp2_emergency, S_IWUSR | S_IRUGO,
366 show_temp_emergency, set_temp_emergency, 1);
367static SENSOR_DEVICE_ATTR(pwm1, S_IWUSR | S_IRUGO, show_pwm, set_pwm, 0);
368static SENSOR_DEVICE_ATTR(pwm2, S_IWUSR | S_IRUGO, show_pwm, set_pwm, 1);
369static SENSOR_DEVICE_ATTR(fan1_input, S_IRUGO, show_fan_input, NULL, 0);
370static SENSOR_DEVICE_ATTR(fan2_input, S_IRUGO, show_fan_input, NULL, 1);
371static SENSOR_DEVICE_ATTR(fan1_fault, S_IRUGO, show_alarm, NULL, 1);
372static SENSOR_DEVICE_ATTR(fan2_fault, S_IRUGO, show_alarm, NULL, 0);
373static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_alarm, NULL, 3);
374static SENSOR_DEVICE_ATTR(temp2_max_alarm, S_IRUGO, show_alarm, NULL, 2);
375static SENSOR_DEVICE_ATTR(temp1_crit_alarm, S_IRUGO, show_alarm, NULL, 7);
376static SENSOR_DEVICE_ATTR(temp2_crit_alarm, S_IRUGO, show_alarm, NULL, 6);
377static SENSOR_DEVICE_ATTR(temp1_emergency_alarm, S_IRUGO, show_alarm, NULL, 5);
378static SENSOR_DEVICE_ATTR(temp2_emergency_alarm, S_IRUGO, show_alarm, NULL, 4);
379
380
381static struct attribute *max6639_attributes[] = {
382 &sensor_dev_attr_temp1_input.dev_attr.attr,
383 &sensor_dev_attr_temp2_input.dev_attr.attr,
384 &sensor_dev_attr_temp1_fault.dev_attr.attr,
385 &sensor_dev_attr_temp2_fault.dev_attr.attr,
386 &sensor_dev_attr_temp1_max.dev_attr.attr,
387 &sensor_dev_attr_temp2_max.dev_attr.attr,
388 &sensor_dev_attr_temp1_crit.dev_attr.attr,
389 &sensor_dev_attr_temp2_crit.dev_attr.attr,
390 &sensor_dev_attr_temp1_emergency.dev_attr.attr,
391 &sensor_dev_attr_temp2_emergency.dev_attr.attr,
392 &sensor_dev_attr_pwm1.dev_attr.attr,
393 &sensor_dev_attr_pwm2.dev_attr.attr,
394 &sensor_dev_attr_fan1_input.dev_attr.attr,
395 &sensor_dev_attr_fan2_input.dev_attr.attr,
396 &sensor_dev_attr_fan1_fault.dev_attr.attr,
397 &sensor_dev_attr_fan2_fault.dev_attr.attr,
398 &sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
399 &sensor_dev_attr_temp2_max_alarm.dev_attr.attr,
400 &sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
401 &sensor_dev_attr_temp2_crit_alarm.dev_attr.attr,
402 &sensor_dev_attr_temp1_emergency_alarm.dev_attr.attr,
403 &sensor_dev_attr_temp2_emergency_alarm.dev_attr.attr,
404 NULL
405};
406
407static const struct attribute_group max6639_group = {
408 .attrs = max6639_attributes,
409};
410
411/*
412 * returns respective index in rpm_ranges table
413 * 1 by default on invalid range
414 */
415static int rpm_range_to_reg(int range)
416{
417 int i;
418
419 for (i = 0; i < ARRAY_SIZE(rpm_ranges); i++) {
420 if (rpm_ranges[i] == range)
421 return i;
422 }
423
424 return 1; /* default: 4000 RPM */
425}
426
427static int max6639_init_client(struct i2c_client *client)
428{
429 struct max6639_data *data = i2c_get_clientdata(client);
430 struct max6639_platform_data *max6639_info =
431 client->dev.platform_data;
432 int i = 0;
433 int rpm_range = 1; /* default: 4000 RPM */
434 int err = 0;
435
436 /* Reset chip to default values, see below for GCONFIG setup */
437 err = i2c_smbus_write_byte_data(client, MAX6639_REG_GCONFIG,
438 MAX6639_GCONFIG_POR);
439 if (err)
440 goto exit;
441
442 /* Fans pulse per revolution is 2 by default */
443 if (max6639_info && max6639_info->ppr > 0 &&
444 max6639_info->ppr < 5)
445 data->ppr = max6639_info->ppr;
446 else
447 data->ppr = 2;
448 data->ppr -= 1;
449 err = i2c_smbus_write_byte_data(client,
450 MAX6639_REG_FAN_PPR(i),
451 data->ppr << 5);
452 if (err)
453 goto exit;
454
455 if (max6639_info)
456 rpm_range = rpm_range_to_reg(max6639_info->rpm_range);
457 data->rpm_range = rpm_range;
458
459 for (i = 0; i < 2; i++) {
460
461 /* Fans config PWM, RPM */
462 err = i2c_smbus_write_byte_data(client,
463 MAX6639_REG_FAN_CONFIG1(i),
464 MAX6639_FAN_CONFIG1_PWM | rpm_range);
465 if (err)
466 goto exit;
467
468 /* Fans PWM polarity high by default */
469 if (max6639_info && max6639_info->pwm_polarity == 0)
470 err = i2c_smbus_write_byte_data(client,
471 MAX6639_REG_FAN_CONFIG2a(i), 0x00);
472 else
473 err = i2c_smbus_write_byte_data(client,
474 MAX6639_REG_FAN_CONFIG2a(i), 0x02);
475 if (err)
476 goto exit;
477
478 /*
479 * /THERM full speed enable,
480 * PWM frequency 25kHz, see also GCONFIG below
481 */
482 err = i2c_smbus_write_byte_data(client,
483 MAX6639_REG_FAN_CONFIG3(i),
484 MAX6639_FAN_CONFIG3_THERM_FULL_SPEED | 0x03);
485 if (err)
486 goto exit;
487
488 /* Max. temp. 80C/90C/100C */
489 data->temp_therm[i] = 80;
490 data->temp_alert[i] = 90;
491 data->temp_ot[i] = 100;
492 err = i2c_smbus_write_byte_data(client,
493 MAX6639_REG_THERM_LIMIT(i),
494 data->temp_therm[i]);
495 if (err)
496 goto exit;
497 err = i2c_smbus_write_byte_data(client,
498 MAX6639_REG_ALERT_LIMIT(i),
499 data->temp_alert[i]);
500 if (err)
501 goto exit;
502 err = i2c_smbus_write_byte_data(client,
503 MAX6639_REG_OT_LIMIT(i), data->temp_ot[i]);
504 if (err)
505 goto exit;
506
507 /* PWM 120/120 (i.e. 100%) */
508 data->pwm[i] = 120;
509 err = i2c_smbus_write_byte_data(client,
510 MAX6639_REG_TARGTDUTY(i), data->pwm[i]);
511 if (err)
512 goto exit;
513 }
514 /* Start monitoring */
515 err = i2c_smbus_write_byte_data(client, MAX6639_REG_GCONFIG,
516 MAX6639_GCONFIG_DISABLE_TIMEOUT | MAX6639_GCONFIG_CH2_LOCAL |
517 MAX6639_GCONFIG_PWM_FREQ_HI);
518exit:
519 return err;
520}
521
522/* Return 0 if detection is successful, -ENODEV otherwise */
523static int max6639_detect(struct i2c_client *client,
524 struct i2c_board_info *info)
525{
526 struct i2c_adapter *adapter = client->adapter;
527 int dev_id, manu_id;
528
529 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
530 return -ENODEV;
531
532 /* Actual detection via device and manufacturer ID */
533 dev_id = i2c_smbus_read_byte_data(client, MAX6639_REG_DEVID);
534 manu_id = i2c_smbus_read_byte_data(client, MAX6639_REG_MANUID);
535 if (dev_id != 0x58 || manu_id != 0x4D)
536 return -ENODEV;
537
538 strlcpy(info->type, "max6639", I2C_NAME_SIZE);
539
540 return 0;
541}
542
543static int max6639_probe(struct i2c_client *client,
544 const struct i2c_device_id *id)
545{
546 struct max6639_data *data;
547 int err;
548
549 data = kzalloc(sizeof(struct max6639_data), GFP_KERNEL);
550 if (!data) {
551 err = -ENOMEM;
552 goto exit;
553 }
554
555 i2c_set_clientdata(client, data);
556 mutex_init(&data->update_lock);
557
558 /* Initialize the max6639 chip */
559 err = max6639_init_client(client);
560 if (err < 0)
561 goto error_free;
562
563 /* Register sysfs hooks */
564 err = sysfs_create_group(&client->dev.kobj, &max6639_group);
565 if (err)
566 goto error_free;
567
568 data->hwmon_dev = hwmon_device_register(&client->dev);
569 if (IS_ERR(data->hwmon_dev)) {
570 err = PTR_ERR(data->hwmon_dev);
571 goto error_remove;
572 }
573
574 dev_info(&client->dev, "temperature sensor and fan control found\n");
575
576 return 0;
577
578error_remove:
579 sysfs_remove_group(&client->dev.kobj, &max6639_group);
580error_free:
581 kfree(data);
582exit:
583 return err;
584}
585
586static int max6639_remove(struct i2c_client *client)
587{
588 struct max6639_data *data = i2c_get_clientdata(client);
589
590 hwmon_device_unregister(data->hwmon_dev);
591 sysfs_remove_group(&client->dev.kobj, &max6639_group);
592
593 kfree(data);
594 return 0;
595}
596
597static int max6639_suspend(struct i2c_client *client, pm_message_t mesg)
598{
599 int data = i2c_smbus_read_byte_data(client, MAX6639_REG_GCONFIG);
600 if (data < 0)
601 return data;
602
603 return i2c_smbus_write_byte_data(client,
604 MAX6639_REG_GCONFIG, data | MAX6639_GCONFIG_STANDBY);
605}
606
607static int max6639_resume(struct i2c_client *client)
608{
609 int data = i2c_smbus_read_byte_data(client, MAX6639_REG_GCONFIG);
610 if (data < 0)
611 return data;
612
613 return i2c_smbus_write_byte_data(client,
614 MAX6639_REG_GCONFIG, data & ~MAX6639_GCONFIG_STANDBY);
615}
616
617static const struct i2c_device_id max6639_id[] = {
618 {"max6639", 0},
619 { }
620};
621
622MODULE_DEVICE_TABLE(i2c, max6639_id);
623
624static struct i2c_driver max6639_driver = {
625 .class = I2C_CLASS_HWMON,
626 .driver = {
627 .name = "max6639",
628 },
629 .probe = max6639_probe,
630 .remove = max6639_remove,
631 .suspend = max6639_suspend,
632 .resume = max6639_resume,
633 .id_table = max6639_id,
634 .detect = max6639_detect,
635 .address_list = normal_i2c,
636};
637
638static int __init max6639_init(void)
639{
640 return i2c_add_driver(&max6639_driver);
641}
642
643static void __exit max6639_exit(void)
644{
645 i2c_del_driver(&max6639_driver);
646}
647
648MODULE_AUTHOR("Roland Stigge <stigge@antcom.de>");
649MODULE_DESCRIPTION("max6639 driver");
650MODULE_LICENSE("GPL");
651
652module_init(max6639_init);
653module_exit(max6639_exit);
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * max6639.c - Support for Maxim MAX6639
4 *
5 * 2-Channel Temperature Monitor with Dual PWM Fan-Speed Controller
6 *
7 * Copyright (C) 2010, 2011 Roland Stigge <stigge@antcom.de>
8 *
9 * based on the initial MAX6639 support from semptian.net
10 * by He Changqing <hechangqing@semptian.com>
11 */
12
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
24/* Addresses to scan */
25static const unsigned short normal_i2c[] = { 0x2c, 0x2e, 0x2f, I2C_CLIENT_END };
26
27/* The MAX6639 registers, valid channel numbers: 0, 1 */
28#define MAX6639_REG_TEMP(ch) (0x00 + (ch))
29#define MAX6639_REG_STATUS 0x02
30#define MAX6639_REG_OUTPUT_MASK 0x03
31#define MAX6639_REG_GCONFIG 0x04
32#define MAX6639_REG_TEMP_EXT(ch) (0x05 + (ch))
33#define MAX6639_REG_ALERT_LIMIT(ch) (0x08 + (ch))
34#define MAX6639_REG_OT_LIMIT(ch) (0x0A + (ch))
35#define MAX6639_REG_THERM_LIMIT(ch) (0x0C + (ch))
36#define MAX6639_REG_FAN_CONFIG1(ch) (0x10 + (ch) * 4)
37#define MAX6639_REG_FAN_CONFIG2a(ch) (0x11 + (ch) * 4)
38#define MAX6639_REG_FAN_CONFIG2b(ch) (0x12 + (ch) * 4)
39#define MAX6639_REG_FAN_CONFIG3(ch) (0x13 + (ch) * 4)
40#define MAX6639_REG_FAN_CNT(ch) (0x20 + (ch))
41#define MAX6639_REG_TARGET_CNT(ch) (0x22 + (ch))
42#define MAX6639_REG_FAN_PPR(ch) (0x24 + (ch))
43#define MAX6639_REG_TARGTDUTY(ch) (0x26 + (ch))
44#define MAX6639_REG_FAN_START_TEMP(ch) (0x28 + (ch))
45#define MAX6639_REG_DEVID 0x3D
46#define MAX6639_REG_MANUID 0x3E
47#define MAX6639_REG_DEVREV 0x3F
48
49/* Register bits */
50#define MAX6639_GCONFIG_STANDBY 0x80
51#define MAX6639_GCONFIG_POR 0x40
52#define MAX6639_GCONFIG_DISABLE_TIMEOUT 0x20
53#define MAX6639_GCONFIG_CH2_LOCAL 0x10
54#define MAX6639_GCONFIG_PWM_FREQ_HI 0x08
55
56#define MAX6639_FAN_CONFIG1_PWM 0x80
57
58#define MAX6639_FAN_CONFIG3_THERM_FULL_SPEED 0x40
59
60static const int rpm_ranges[] = { 2000, 4000, 8000, 16000 };
61
62#define FAN_FROM_REG(val, rpm_range) ((val) == 0 || (val) == 255 ? \
63 0 : (rpm_ranges[rpm_range] * 30) / (val))
64#define TEMP_LIMIT_TO_REG(val) clamp_val((val) / 1000, 0, 255)
65
66/*
67 * Client data (each client gets its own)
68 */
69struct max6639_data {
70 struct i2c_client *client;
71 struct mutex update_lock;
72 char valid; /* !=0 if following fields are valid */
73 unsigned long last_updated; /* In jiffies */
74
75 /* Register values sampled regularly */
76 u16 temp[2]; /* Temperature, in 1/8 C, 0..255 C */
77 bool temp_fault[2]; /* Detected temperature diode failure */
78 u8 fan[2]; /* Register value: TACH count for fans >=30 */
79 u8 status; /* Detected channel alarms and fan failures */
80
81 /* Register values only written to */
82 u8 pwm[2]; /* Register value: Duty cycle 0..120 */
83 u8 temp_therm[2]; /* THERM Temperature, 0..255 C (->_max) */
84 u8 temp_alert[2]; /* ALERT Temperature, 0..255 C (->_crit) */
85 u8 temp_ot[2]; /* OT Temperature, 0..255 C (->_emergency) */
86
87 /* Register values initialized only once */
88 u8 ppr; /* Pulses per rotation 0..3 for 1..4 ppr */
89 u8 rpm_range; /* Index in above rpm_ranges table */
90};
91
92static struct max6639_data *max6639_update_device(struct device *dev)
93{
94 struct max6639_data *data = dev_get_drvdata(dev);
95 struct i2c_client *client = data->client;
96 struct max6639_data *ret = data;
97 int i;
98 int status_reg;
99
100 mutex_lock(&data->update_lock);
101
102 if (time_after(jiffies, data->last_updated + 2 * HZ) || !data->valid) {
103 int res;
104
105 dev_dbg(&client->dev, "Starting max6639 update\n");
106
107 status_reg = i2c_smbus_read_byte_data(client,
108 MAX6639_REG_STATUS);
109 if (status_reg < 0) {
110 ret = ERR_PTR(status_reg);
111 goto abort;
112 }
113
114 data->status = status_reg;
115
116 for (i = 0; i < 2; i++) {
117 res = i2c_smbus_read_byte_data(client,
118 MAX6639_REG_FAN_CNT(i));
119 if (res < 0) {
120 ret = ERR_PTR(res);
121 goto abort;
122 }
123 data->fan[i] = res;
124
125 res = i2c_smbus_read_byte_data(client,
126 MAX6639_REG_TEMP_EXT(i));
127 if (res < 0) {
128 ret = ERR_PTR(res);
129 goto abort;
130 }
131 data->temp[i] = res >> 5;
132 data->temp_fault[i] = res & 0x01;
133
134 res = i2c_smbus_read_byte_data(client,
135 MAX6639_REG_TEMP(i));
136 if (res < 0) {
137 ret = ERR_PTR(res);
138 goto abort;
139 }
140 data->temp[i] |= res << 3;
141 }
142
143 data->last_updated = jiffies;
144 data->valid = 1;
145 }
146abort:
147 mutex_unlock(&data->update_lock);
148
149 return ret;
150}
151
152static ssize_t temp_input_show(struct device *dev,
153 struct device_attribute *dev_attr, char *buf)
154{
155 long temp;
156 struct max6639_data *data = max6639_update_device(dev);
157 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
158
159 if (IS_ERR(data))
160 return PTR_ERR(data);
161
162 temp = data->temp[attr->index] * 125;
163 return sprintf(buf, "%ld\n", temp);
164}
165
166static ssize_t temp_fault_show(struct device *dev,
167 struct device_attribute *dev_attr, char *buf)
168{
169 struct max6639_data *data = max6639_update_device(dev);
170 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
171
172 if (IS_ERR(data))
173 return PTR_ERR(data);
174
175 return sprintf(buf, "%d\n", data->temp_fault[attr->index]);
176}
177
178static ssize_t temp_max_show(struct device *dev,
179 struct device_attribute *dev_attr, char *buf)
180{
181 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
182 struct max6639_data *data = dev_get_drvdata(dev);
183
184 return sprintf(buf, "%d\n", (data->temp_therm[attr->index] * 1000));
185}
186
187static ssize_t temp_max_store(struct device *dev,
188 struct device_attribute *dev_attr,
189 const char *buf, size_t count)
190{
191 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
192 struct max6639_data *data = dev_get_drvdata(dev);
193 struct i2c_client *client = data->client;
194 unsigned long val;
195 int res;
196
197 res = kstrtoul(buf, 10, &val);
198 if (res)
199 return res;
200
201 mutex_lock(&data->update_lock);
202 data->temp_therm[attr->index] = TEMP_LIMIT_TO_REG(val);
203 i2c_smbus_write_byte_data(client,
204 MAX6639_REG_THERM_LIMIT(attr->index),
205 data->temp_therm[attr->index]);
206 mutex_unlock(&data->update_lock);
207 return count;
208}
209
210static ssize_t temp_crit_show(struct device *dev,
211 struct device_attribute *dev_attr, char *buf)
212{
213 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
214 struct max6639_data *data = dev_get_drvdata(dev);
215
216 return sprintf(buf, "%d\n", (data->temp_alert[attr->index] * 1000));
217}
218
219static ssize_t temp_crit_store(struct device *dev,
220 struct device_attribute *dev_attr,
221 const char *buf, size_t count)
222{
223 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
224 struct max6639_data *data = dev_get_drvdata(dev);
225 struct i2c_client *client = data->client;
226 unsigned long val;
227 int res;
228
229 res = kstrtoul(buf, 10, &val);
230 if (res)
231 return res;
232
233 mutex_lock(&data->update_lock);
234 data->temp_alert[attr->index] = TEMP_LIMIT_TO_REG(val);
235 i2c_smbus_write_byte_data(client,
236 MAX6639_REG_ALERT_LIMIT(attr->index),
237 data->temp_alert[attr->index]);
238 mutex_unlock(&data->update_lock);
239 return count;
240}
241
242static ssize_t temp_emergency_show(struct device *dev,
243 struct device_attribute *dev_attr,
244 char *buf)
245{
246 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
247 struct max6639_data *data = dev_get_drvdata(dev);
248
249 return sprintf(buf, "%d\n", (data->temp_ot[attr->index] * 1000));
250}
251
252static ssize_t temp_emergency_store(struct device *dev,
253 struct device_attribute *dev_attr,
254 const char *buf, size_t count)
255{
256 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
257 struct max6639_data *data = dev_get_drvdata(dev);
258 struct i2c_client *client = data->client;
259 unsigned long val;
260 int res;
261
262 res = kstrtoul(buf, 10, &val);
263 if (res)
264 return res;
265
266 mutex_lock(&data->update_lock);
267 data->temp_ot[attr->index] = TEMP_LIMIT_TO_REG(val);
268 i2c_smbus_write_byte_data(client,
269 MAX6639_REG_OT_LIMIT(attr->index),
270 data->temp_ot[attr->index]);
271 mutex_unlock(&data->update_lock);
272 return count;
273}
274
275static ssize_t pwm_show(struct device *dev, struct device_attribute *dev_attr,
276 char *buf)
277{
278 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
279 struct max6639_data *data = dev_get_drvdata(dev);
280
281 return sprintf(buf, "%d\n", data->pwm[attr->index] * 255 / 120);
282}
283
284static ssize_t pwm_store(struct device *dev,
285 struct device_attribute *dev_attr, const char *buf,
286 size_t count)
287{
288 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
289 struct max6639_data *data = dev_get_drvdata(dev);
290 struct i2c_client *client = data->client;
291 unsigned long val;
292 int res;
293
294 res = kstrtoul(buf, 10, &val);
295 if (res)
296 return res;
297
298 val = clamp_val(val, 0, 255);
299
300 mutex_lock(&data->update_lock);
301 data->pwm[attr->index] = (u8)(val * 120 / 255);
302 i2c_smbus_write_byte_data(client,
303 MAX6639_REG_TARGTDUTY(attr->index),
304 data->pwm[attr->index]);
305 mutex_unlock(&data->update_lock);
306 return count;
307}
308
309static ssize_t fan_input_show(struct device *dev,
310 struct device_attribute *dev_attr, char *buf)
311{
312 struct max6639_data *data = max6639_update_device(dev);
313 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
314
315 if (IS_ERR(data))
316 return PTR_ERR(data);
317
318 return sprintf(buf, "%d\n", FAN_FROM_REG(data->fan[attr->index],
319 data->rpm_range));
320}
321
322static ssize_t alarm_show(struct device *dev,
323 struct device_attribute *dev_attr, char *buf)
324{
325 struct max6639_data *data = max6639_update_device(dev);
326 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
327
328 if (IS_ERR(data))
329 return PTR_ERR(data);
330
331 return sprintf(buf, "%d\n", !!(data->status & (1 << attr->index)));
332}
333
334static SENSOR_DEVICE_ATTR_RO(temp1_input, temp_input, 0);
335static SENSOR_DEVICE_ATTR_RO(temp2_input, temp_input, 1);
336static SENSOR_DEVICE_ATTR_RO(temp1_fault, temp_fault, 0);
337static SENSOR_DEVICE_ATTR_RO(temp2_fault, temp_fault, 1);
338static SENSOR_DEVICE_ATTR_RW(temp1_max, temp_max, 0);
339static SENSOR_DEVICE_ATTR_RW(temp2_max, temp_max, 1);
340static SENSOR_DEVICE_ATTR_RW(temp1_crit, temp_crit, 0);
341static SENSOR_DEVICE_ATTR_RW(temp2_crit, temp_crit, 1);
342static SENSOR_DEVICE_ATTR_RW(temp1_emergency, temp_emergency, 0);
343static SENSOR_DEVICE_ATTR_RW(temp2_emergency, temp_emergency, 1);
344static SENSOR_DEVICE_ATTR_RW(pwm1, pwm, 0);
345static SENSOR_DEVICE_ATTR_RW(pwm2, pwm, 1);
346static SENSOR_DEVICE_ATTR_RO(fan1_input, fan_input, 0);
347static SENSOR_DEVICE_ATTR_RO(fan2_input, fan_input, 1);
348static SENSOR_DEVICE_ATTR_RO(fan1_fault, alarm, 1);
349static SENSOR_DEVICE_ATTR_RO(fan2_fault, alarm, 0);
350static SENSOR_DEVICE_ATTR_RO(temp1_max_alarm, alarm, 3);
351static SENSOR_DEVICE_ATTR_RO(temp2_max_alarm, alarm, 2);
352static SENSOR_DEVICE_ATTR_RO(temp1_crit_alarm, alarm, 7);
353static SENSOR_DEVICE_ATTR_RO(temp2_crit_alarm, alarm, 6);
354static SENSOR_DEVICE_ATTR_RO(temp1_emergency_alarm, alarm, 5);
355static SENSOR_DEVICE_ATTR_RO(temp2_emergency_alarm, alarm, 4);
356
357
358static struct attribute *max6639_attrs[] = {
359 &sensor_dev_attr_temp1_input.dev_attr.attr,
360 &sensor_dev_attr_temp2_input.dev_attr.attr,
361 &sensor_dev_attr_temp1_fault.dev_attr.attr,
362 &sensor_dev_attr_temp2_fault.dev_attr.attr,
363 &sensor_dev_attr_temp1_max.dev_attr.attr,
364 &sensor_dev_attr_temp2_max.dev_attr.attr,
365 &sensor_dev_attr_temp1_crit.dev_attr.attr,
366 &sensor_dev_attr_temp2_crit.dev_attr.attr,
367 &sensor_dev_attr_temp1_emergency.dev_attr.attr,
368 &sensor_dev_attr_temp2_emergency.dev_attr.attr,
369 &sensor_dev_attr_pwm1.dev_attr.attr,
370 &sensor_dev_attr_pwm2.dev_attr.attr,
371 &sensor_dev_attr_fan1_input.dev_attr.attr,
372 &sensor_dev_attr_fan2_input.dev_attr.attr,
373 &sensor_dev_attr_fan1_fault.dev_attr.attr,
374 &sensor_dev_attr_fan2_fault.dev_attr.attr,
375 &sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
376 &sensor_dev_attr_temp2_max_alarm.dev_attr.attr,
377 &sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
378 &sensor_dev_attr_temp2_crit_alarm.dev_attr.attr,
379 &sensor_dev_attr_temp1_emergency_alarm.dev_attr.attr,
380 &sensor_dev_attr_temp2_emergency_alarm.dev_attr.attr,
381 NULL
382};
383ATTRIBUTE_GROUPS(max6639);
384
385/*
386 * returns respective index in rpm_ranges table
387 * 1 by default on invalid range
388 */
389static int rpm_range_to_reg(int range)
390{
391 int i;
392
393 for (i = 0; i < ARRAY_SIZE(rpm_ranges); i++) {
394 if (rpm_ranges[i] == range)
395 return i;
396 }
397
398 return 1; /* default: 4000 RPM */
399}
400
401static int max6639_init_client(struct i2c_client *client,
402 struct max6639_data *data)
403{
404 struct max6639_platform_data *max6639_info =
405 dev_get_platdata(&client->dev);
406 int i;
407 int rpm_range = 1; /* default: 4000 RPM */
408 int err;
409
410 /* Reset chip to default values, see below for GCONFIG setup */
411 err = i2c_smbus_write_byte_data(client, MAX6639_REG_GCONFIG,
412 MAX6639_GCONFIG_POR);
413 if (err)
414 goto exit;
415
416 /* Fans pulse per revolution is 2 by default */
417 if (max6639_info && max6639_info->ppr > 0 &&
418 max6639_info->ppr < 5)
419 data->ppr = max6639_info->ppr;
420 else
421 data->ppr = 2;
422 data->ppr -= 1;
423
424 if (max6639_info)
425 rpm_range = rpm_range_to_reg(max6639_info->rpm_range);
426 data->rpm_range = rpm_range;
427
428 for (i = 0; i < 2; i++) {
429
430 /* Set Fan pulse per revolution */
431 err = i2c_smbus_write_byte_data(client,
432 MAX6639_REG_FAN_PPR(i),
433 data->ppr << 6);
434 if (err)
435 goto exit;
436
437 /* Fans config PWM, RPM */
438 err = i2c_smbus_write_byte_data(client,
439 MAX6639_REG_FAN_CONFIG1(i),
440 MAX6639_FAN_CONFIG1_PWM | rpm_range);
441 if (err)
442 goto exit;
443
444 /* Fans PWM polarity high by default */
445 if (max6639_info && max6639_info->pwm_polarity == 0)
446 err = i2c_smbus_write_byte_data(client,
447 MAX6639_REG_FAN_CONFIG2a(i), 0x00);
448 else
449 err = i2c_smbus_write_byte_data(client,
450 MAX6639_REG_FAN_CONFIG2a(i), 0x02);
451 if (err)
452 goto exit;
453
454 /*
455 * /THERM full speed enable,
456 * PWM frequency 25kHz, see also GCONFIG below
457 */
458 err = i2c_smbus_write_byte_data(client,
459 MAX6639_REG_FAN_CONFIG3(i),
460 MAX6639_FAN_CONFIG3_THERM_FULL_SPEED | 0x03);
461 if (err)
462 goto exit;
463
464 /* Max. temp. 80C/90C/100C */
465 data->temp_therm[i] = 80;
466 data->temp_alert[i] = 90;
467 data->temp_ot[i] = 100;
468 err = i2c_smbus_write_byte_data(client,
469 MAX6639_REG_THERM_LIMIT(i),
470 data->temp_therm[i]);
471 if (err)
472 goto exit;
473 err = i2c_smbus_write_byte_data(client,
474 MAX6639_REG_ALERT_LIMIT(i),
475 data->temp_alert[i]);
476 if (err)
477 goto exit;
478 err = i2c_smbus_write_byte_data(client,
479 MAX6639_REG_OT_LIMIT(i), data->temp_ot[i]);
480 if (err)
481 goto exit;
482
483 /* PWM 120/120 (i.e. 100%) */
484 data->pwm[i] = 120;
485 err = i2c_smbus_write_byte_data(client,
486 MAX6639_REG_TARGTDUTY(i), data->pwm[i]);
487 if (err)
488 goto exit;
489 }
490 /* Start monitoring */
491 err = i2c_smbus_write_byte_data(client, MAX6639_REG_GCONFIG,
492 MAX6639_GCONFIG_DISABLE_TIMEOUT | MAX6639_GCONFIG_CH2_LOCAL |
493 MAX6639_GCONFIG_PWM_FREQ_HI);
494exit:
495 return err;
496}
497
498/* Return 0 if detection is successful, -ENODEV otherwise */
499static int max6639_detect(struct i2c_client *client,
500 struct i2c_board_info *info)
501{
502 struct i2c_adapter *adapter = client->adapter;
503 int dev_id, manu_id;
504
505 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
506 return -ENODEV;
507
508 /* Actual detection via device and manufacturer ID */
509 dev_id = i2c_smbus_read_byte_data(client, MAX6639_REG_DEVID);
510 manu_id = i2c_smbus_read_byte_data(client, MAX6639_REG_MANUID);
511 if (dev_id != 0x58 || manu_id != 0x4D)
512 return -ENODEV;
513
514 strlcpy(info->type, "max6639", I2C_NAME_SIZE);
515
516 return 0;
517}
518
519static int max6639_probe(struct i2c_client *client,
520 const struct i2c_device_id *id)
521{
522 struct device *dev = &client->dev;
523 struct max6639_data *data;
524 struct device *hwmon_dev;
525 int err;
526
527 data = devm_kzalloc(dev, sizeof(struct max6639_data), GFP_KERNEL);
528 if (!data)
529 return -ENOMEM;
530
531 data->client = client;
532 mutex_init(&data->update_lock);
533
534 /* Initialize the max6639 chip */
535 err = max6639_init_client(client, data);
536 if (err < 0)
537 return err;
538
539 hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
540 data,
541 max6639_groups);
542 return PTR_ERR_OR_ZERO(hwmon_dev);
543}
544
545#ifdef CONFIG_PM_SLEEP
546static int max6639_suspend(struct device *dev)
547{
548 struct i2c_client *client = to_i2c_client(dev);
549 int data = i2c_smbus_read_byte_data(client, MAX6639_REG_GCONFIG);
550 if (data < 0)
551 return data;
552
553 return i2c_smbus_write_byte_data(client,
554 MAX6639_REG_GCONFIG, data | MAX6639_GCONFIG_STANDBY);
555}
556
557static int max6639_resume(struct device *dev)
558{
559 struct i2c_client *client = to_i2c_client(dev);
560 int data = i2c_smbus_read_byte_data(client, MAX6639_REG_GCONFIG);
561 if (data < 0)
562 return data;
563
564 return i2c_smbus_write_byte_data(client,
565 MAX6639_REG_GCONFIG, data & ~MAX6639_GCONFIG_STANDBY);
566}
567#endif /* CONFIG_PM_SLEEP */
568
569static const struct i2c_device_id max6639_id[] = {
570 {"max6639", 0},
571 { }
572};
573
574MODULE_DEVICE_TABLE(i2c, max6639_id);
575
576static SIMPLE_DEV_PM_OPS(max6639_pm_ops, max6639_suspend, max6639_resume);
577
578static struct i2c_driver max6639_driver = {
579 .class = I2C_CLASS_HWMON,
580 .driver = {
581 .name = "max6639",
582 .pm = &max6639_pm_ops,
583 },
584 .probe = max6639_probe,
585 .id_table = max6639_id,
586 .detect = max6639_detect,
587 .address_list = normal_i2c,
588};
589
590module_i2c_driver(max6639_driver);
591
592MODULE_AUTHOR("Roland Stigge <stigge@antcom.de>");
593MODULE_DESCRIPTION("max6639 driver");
594MODULE_LICENSE("GPL");