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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, rpm_range)	((val) == 0 || (val) == 255 ? \
 76				0 : (rpm_ranges[rpm_range] * 30) / (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 = kstrtoul(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 = kstrtoul(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 = kstrtoul(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 = kstrtoul(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->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;
433	int rpm_range = 1; /* default: 4000 RPM */
434	int err;
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
450	if (max6639_info)
451		rpm_range = rpm_range_to_reg(max6639_info->rpm_range);
452	data->rpm_range = rpm_range;
453
454	for (i = 0; i < 2; i++) {
455
456		/* Set Fan pulse per revolution */
457		err = i2c_smbus_write_byte_data(client,
458				MAX6639_REG_FAN_PPR(i),
459				data->ppr << 6);
460		if (err)
461			goto exit;
462
463		/* Fans config PWM, RPM */
464		err = i2c_smbus_write_byte_data(client,
465			MAX6639_REG_FAN_CONFIG1(i),
466			MAX6639_FAN_CONFIG1_PWM | rpm_range);
467		if (err)
468			goto exit;
469
470		/* Fans PWM polarity high by default */
471		if (max6639_info && max6639_info->pwm_polarity == 0)
472			err = i2c_smbus_write_byte_data(client,
473				MAX6639_REG_FAN_CONFIG2a(i), 0x00);
474		else
475			err = i2c_smbus_write_byte_data(client,
476				MAX6639_REG_FAN_CONFIG2a(i), 0x02);
477		if (err)
478			goto exit;
479
480		/*
481		 * /THERM full speed enable,
482		 * PWM frequency 25kHz, see also GCONFIG below
483		 */
484		err = i2c_smbus_write_byte_data(client,
485			MAX6639_REG_FAN_CONFIG3(i),
486			MAX6639_FAN_CONFIG3_THERM_FULL_SPEED | 0x03);
487		if (err)
488			goto exit;
489
490		/* Max. temp. 80C/90C/100C */
491		data->temp_therm[i] = 80;
492		data->temp_alert[i] = 90;
493		data->temp_ot[i] = 100;
494		err = i2c_smbus_write_byte_data(client,
495				MAX6639_REG_THERM_LIMIT(i),
496				data->temp_therm[i]);
497		if (err)
498			goto exit;
499		err = i2c_smbus_write_byte_data(client,
500				MAX6639_REG_ALERT_LIMIT(i),
501				data->temp_alert[i]);
502		if (err)
503			goto exit;
504		err = i2c_smbus_write_byte_data(client,
505				MAX6639_REG_OT_LIMIT(i), data->temp_ot[i]);
506		if (err)
507			goto exit;
508
509		/* PWM 120/120 (i.e. 100%) */
510		data->pwm[i] = 120;
511		err = i2c_smbus_write_byte_data(client,
512				MAX6639_REG_TARGTDUTY(i), data->pwm[i]);
513		if (err)
514			goto exit;
515	}
516	/* Start monitoring */
517	err = i2c_smbus_write_byte_data(client, MAX6639_REG_GCONFIG,
518		MAX6639_GCONFIG_DISABLE_TIMEOUT | MAX6639_GCONFIG_CH2_LOCAL |
519		MAX6639_GCONFIG_PWM_FREQ_HI);
520exit:
521	return err;
522}
523
524/* Return 0 if detection is successful, -ENODEV otherwise */
525static int max6639_detect(struct i2c_client *client,
526			  struct i2c_board_info *info)
527{
528	struct i2c_adapter *adapter = client->adapter;
529	int dev_id, manu_id;
530
531	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
532		return -ENODEV;
533
534	/* Actual detection via device and manufacturer ID */
535	dev_id = i2c_smbus_read_byte_data(client, MAX6639_REG_DEVID);
536	manu_id = i2c_smbus_read_byte_data(client, MAX6639_REG_MANUID);
537	if (dev_id != 0x58 || manu_id != 0x4D)
538		return -ENODEV;
539
540	strlcpy(info->type, "max6639", I2C_NAME_SIZE);
541
542	return 0;
543}
544
545static int max6639_probe(struct i2c_client *client,
546			 const struct i2c_device_id *id)
547{
548	struct max6639_data *data;
549	int err;
550
551	data = kzalloc(sizeof(struct max6639_data), GFP_KERNEL);
552	if (!data) {
553		err = -ENOMEM;
554		goto exit;
555	}
556
557	i2c_set_clientdata(client, data);
558	mutex_init(&data->update_lock);
559
560	/* Initialize the max6639 chip */
561	err = max6639_init_client(client);
562	if (err < 0)
563		goto error_free;
564
565	/* Register sysfs hooks */
566	err = sysfs_create_group(&client->dev.kobj, &max6639_group);
567	if (err)
568		goto error_free;
569
570	data->hwmon_dev = hwmon_device_register(&client->dev);
571	if (IS_ERR(data->hwmon_dev)) {
572		err = PTR_ERR(data->hwmon_dev);
573		goto error_remove;
574	}
575
576	dev_info(&client->dev, "temperature sensor and fan control found\n");
577
578	return 0;
579
580error_remove:
581	sysfs_remove_group(&client->dev.kobj, &max6639_group);
582error_free:
583	kfree(data);
584exit:
585	return err;
586}
587
588static int max6639_remove(struct i2c_client *client)
589{
590	struct max6639_data *data = i2c_get_clientdata(client);
591
592	hwmon_device_unregister(data->hwmon_dev);
593	sysfs_remove_group(&client->dev.kobj, &max6639_group);
594
595	kfree(data);
596	return 0;
597}
598
599#ifdef CONFIG_PM_SLEEP
600static int max6639_suspend(struct device *dev)
601{
602	struct i2c_client *client = to_i2c_client(dev);
603	int data = i2c_smbus_read_byte_data(client, MAX6639_REG_GCONFIG);
604	if (data < 0)
605		return data;
606
607	return i2c_smbus_write_byte_data(client,
608			MAX6639_REG_GCONFIG, data | MAX6639_GCONFIG_STANDBY);
609}
610
611static int max6639_resume(struct device *dev)
612{
613	struct i2c_client *client = to_i2c_client(dev);
614	int data = i2c_smbus_read_byte_data(client, MAX6639_REG_GCONFIG);
615	if (data < 0)
616		return data;
617
618	return i2c_smbus_write_byte_data(client,
619			MAX6639_REG_GCONFIG, data & ~MAX6639_GCONFIG_STANDBY);
620}
621#endif /* CONFIG_PM_SLEEP */
622
623static const struct i2c_device_id max6639_id[] = {
624	{"max6639", 0},
625	{ }
626};
627
628MODULE_DEVICE_TABLE(i2c, max6639_id);
629
630static const struct dev_pm_ops max6639_pm_ops = {
631	SET_SYSTEM_SLEEP_PM_OPS(max6639_suspend, max6639_resume)
632};
633
634static struct i2c_driver max6639_driver = {
635	.class = I2C_CLASS_HWMON,
636	.driver = {
637		   .name = "max6639",
638		   .pm = &max6639_pm_ops,
639		   },
640	.probe = max6639_probe,
641	.remove = max6639_remove,
642	.id_table = max6639_id,
643	.detect = max6639_detect,
644	.address_list = normal_i2c,
645};
646
647module_i2c_driver(max6639_driver);
648
649MODULE_AUTHOR("Roland Stigge <stigge@antcom.de>");
650MODULE_DESCRIPTION("max6639 driver");
651MODULE_LICENSE("GPL");