1/*
2 * emc2103.c - Support for SMSC EMC2103
3 * Copyright (c) 2010 SMSC
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
18 */
19
20#include <linux/module.h>
21#include <linux/init.h>
22#include <linux/slab.h>
23#include <linux/jiffies.h>
24#include <linux/i2c.h>
25#include <linux/hwmon.h>
26#include <linux/hwmon-sysfs.h>
27#include <linux/err.h>
28#include <linux/mutex.h>
29
30/* Addresses scanned */
31static const unsigned short normal_i2c[] = { 0x2E, I2C_CLIENT_END };
32
33static const u8 REG_TEMP[4] = { 0x00, 0x02, 0x04, 0x06 };
34static const u8 REG_TEMP_MIN[4] = { 0x3c, 0x38, 0x39, 0x3a };
35static const u8 REG_TEMP_MAX[4] = { 0x34, 0x30, 0x31, 0x32 };
36
37#define REG_CONF1		0x20
38#define REG_TEMP_MAX_ALARM	0x24
39#define REG_TEMP_MIN_ALARM	0x25
40#define REG_FAN_CONF1		0x42
41#define REG_FAN_TARGET_LO	0x4c
42#define REG_FAN_TARGET_HI	0x4d
43#define REG_FAN_TACH_HI		0x4e
44#define REG_FAN_TACH_LO		0x4f
45#define REG_PRODUCT_ID		0xfd
46#define REG_MFG_ID		0xfe
47
48/* equation 4 from datasheet: rpm = (3932160 * multipler) / count */
49#define FAN_RPM_FACTOR		3932160
50
51/*
52 * 2103-2 and 2103-4's 3rd temperature sensor can be connected to two diodes
53 * in anti-parallel mode, and in this configuration both can be read
54 * independently (so we have 4 temperature inputs).  The device can't
55 * detect if it's connected in this mode, so we have to manually enable
56 * it.  Default is to leave the device in the state it's already in (-1).
57 * This parameter allows APD mode to be optionally forced on or off
58 */
59static int apd = -1;
60module_param(apd, bint, 0);
61MODULE_PARM_DESC(init, "Set to zero to disable anti-parallel diode mode");
62
63struct temperature {
64	s8	degrees;
65	u8	fraction;	/* 0-7 multiples of 0.125 */
66};
67
68struct emc2103_data {
69	struct i2c_client	*client;
70	const struct		attribute_group *groups[4];
71	struct mutex		update_lock;
72	bool			valid;		/* registers are valid */
73	bool			fan_rpm_control;
74	int			temp_count;	/* num of temp sensors */
75	unsigned long		last_updated;	/* in jiffies */
76	struct temperature	temp[4];	/* internal + 3 external */
77	s8			temp_min[4];	/* no fractional part */
78	s8			temp_max[4];    /* no fractional part */
79	u8			temp_min_alarm;
80	u8			temp_max_alarm;
81	u8			fan_multiplier;
82	u16			fan_tach;
83	u16			fan_target;
84};
85
86static int read_u8_from_i2c(struct i2c_client *client, u8 i2c_reg, u8 *output)
87{
88	int status = i2c_smbus_read_byte_data(client, i2c_reg);
89	if (status < 0) {
90		dev_warn(&client->dev, "reg 0x%02x, err %d\n",
91			i2c_reg, status);
92	} else {
93		*output = status;
94	}
95	return status;
96}
97
98static void read_temp_from_i2c(struct i2c_client *client, u8 i2c_reg,
99			       struct temperature *temp)
100{
101	u8 degrees, fractional;
102
103	if (read_u8_from_i2c(client, i2c_reg, &degrees) < 0)
104		return;
105
106	if (read_u8_from_i2c(client, i2c_reg + 1, &fractional) < 0)
107		return;
108
109	temp->degrees = degrees;
110	temp->fraction = (fractional & 0xe0) >> 5;
111}
112
113static void read_fan_from_i2c(struct i2c_client *client, u16 *output,
114			      u8 hi_addr, u8 lo_addr)
115{
116	u8 high_byte, lo_byte;
117
118	if (read_u8_from_i2c(client, hi_addr, &high_byte) < 0)
119		return;
120
121	if (read_u8_from_i2c(client, lo_addr, &lo_byte) < 0)
122		return;
123
124	*output = ((u16)high_byte << 5) | (lo_byte >> 3);
125}
126
127static void write_fan_target_to_i2c(struct i2c_client *client, u16 new_target)
128{
129	u8 high_byte = (new_target & 0x1fe0) >> 5;
130	u8 low_byte = (new_target & 0x001f) << 3;
131	i2c_smbus_write_byte_data(client, REG_FAN_TARGET_LO, low_byte);
132	i2c_smbus_write_byte_data(client, REG_FAN_TARGET_HI, high_byte);
133}
134
135static void read_fan_config_from_i2c(struct i2c_client *client)
136
137{
138	struct emc2103_data *data = i2c_get_clientdata(client);
139	u8 conf1;
140
141	if (read_u8_from_i2c(client, REG_FAN_CONF1, &conf1) < 0)
142		return;
143
144	data->fan_multiplier = 1 << ((conf1 & 0x60) >> 5);
145	data->fan_rpm_control = (conf1 & 0x80) != 0;
146}
147
148static struct emc2103_data *emc2103_update_device(struct device *dev)
149{
150	struct emc2103_data *data = dev_get_drvdata(dev);
151	struct i2c_client *client = data->client;
152
153	mutex_lock(&data->update_lock);
154
155	if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
156	    || !data->valid) {
157		int i;
158
159		for (i = 0; i < data->temp_count; i++) {
160			read_temp_from_i2c(client, REG_TEMP[i], &data->temp[i]);
161			read_u8_from_i2c(client, REG_TEMP_MIN[i],
162				&data->temp_min[i]);
163			read_u8_from_i2c(client, REG_TEMP_MAX[i],
164				&data->temp_max[i]);
165		}
166
167		read_u8_from_i2c(client, REG_TEMP_MIN_ALARM,
168			&data->temp_min_alarm);
169		read_u8_from_i2c(client, REG_TEMP_MAX_ALARM,
170			&data->temp_max_alarm);
171
172		read_fan_from_i2c(client, &data->fan_tach,
173			REG_FAN_TACH_HI, REG_FAN_TACH_LO);
174		read_fan_from_i2c(client, &data->fan_target,
175			REG_FAN_TARGET_HI, REG_FAN_TARGET_LO);
176		read_fan_config_from_i2c(client);
177
178		data->last_updated = jiffies;
179		data->valid = true;
180	}
181
182	mutex_unlock(&data->update_lock);
183
184	return data;
185}
186
187static ssize_t
188show_temp(struct device *dev, struct device_attribute *da, char *buf)
189{
190	int nr = to_sensor_dev_attr(da)->index;
191	struct emc2103_data *data = emc2103_update_device(dev);
192	int millidegrees = data->temp[nr].degrees * 1000
193		+ data->temp[nr].fraction * 125;
194	return sprintf(buf, "%d\n", millidegrees);
195}
196
197static ssize_t
198show_temp_min(struct device *dev, struct device_attribute *da, char *buf)
199{
200	int nr = to_sensor_dev_attr(da)->index;
201	struct emc2103_data *data = emc2103_update_device(dev);
202	int millidegrees = data->temp_min[nr] * 1000;
203	return sprintf(buf, "%d\n", millidegrees);
204}
205
206static ssize_t
207show_temp_max(struct device *dev, struct device_attribute *da, char *buf)
208{
209	int nr = to_sensor_dev_attr(da)->index;
210	struct emc2103_data *data = emc2103_update_device(dev);
211	int millidegrees = data->temp_max[nr] * 1000;
212	return sprintf(buf, "%d\n", millidegrees);
213}
214
215static ssize_t
216show_temp_fault(struct device *dev, struct device_attribute *da, char *buf)
217{
218	int nr = to_sensor_dev_attr(da)->index;
219	struct emc2103_data *data = emc2103_update_device(dev);
220	bool fault = (data->temp[nr].degrees == -128);
221	return sprintf(buf, "%d\n", fault ? 1 : 0);
222}
223
224static ssize_t
225show_temp_min_alarm(struct device *dev, struct device_attribute *da, char *buf)
226{
227	int nr = to_sensor_dev_attr(da)->index;
228	struct emc2103_data *data = emc2103_update_device(dev);
229	bool alarm = data->temp_min_alarm & (1 << nr);
230	return sprintf(buf, "%d\n", alarm ? 1 : 0);
231}
232
233static ssize_t
234show_temp_max_alarm(struct device *dev, struct device_attribute *da, char *buf)
235{
236	int nr = to_sensor_dev_attr(da)->index;
237	struct emc2103_data *data = emc2103_update_device(dev);
238	bool alarm = data->temp_max_alarm & (1 << nr);
239	return sprintf(buf, "%d\n", alarm ? 1 : 0);
240}
241
242static ssize_t set_temp_min(struct device *dev, struct device_attribute *da,
243			    const char *buf, size_t count)
244{
245	int nr = to_sensor_dev_attr(da)->index;
246	struct emc2103_data *data = dev_get_drvdata(dev);
247	struct i2c_client *client = data->client;
248	long val;
249
250	int result = kstrtol(buf, 10, &val);
251	if (result < 0)
252		return result;
253
254	val = clamp_val(DIV_ROUND_CLOSEST(val, 1000), -63, 127);
255
256	mutex_lock(&data->update_lock);
257	data->temp_min[nr] = val;
258	i2c_smbus_write_byte_data(client, REG_TEMP_MIN[nr], val);
259	mutex_unlock(&data->update_lock);
260
261	return count;
262}
263
264static ssize_t set_temp_max(struct device *dev, struct device_attribute *da,
265			    const char *buf, size_t count)
266{
267	int nr = to_sensor_dev_attr(da)->index;
268	struct emc2103_data *data = dev_get_drvdata(dev);
269	struct i2c_client *client = data->client;
270	long val;
271
272	int result = kstrtol(buf, 10, &val);
273	if (result < 0)
274		return result;
275
276	val = clamp_val(DIV_ROUND_CLOSEST(val, 1000), -63, 127);
277
278	mutex_lock(&data->update_lock);
279	data->temp_max[nr] = val;
280	i2c_smbus_write_byte_data(client, REG_TEMP_MAX[nr], val);
281	mutex_unlock(&data->update_lock);
282
283	return count;
284}
285
286static ssize_t
287show_fan(struct device *dev, struct device_attribute *da, char *buf)
288{
289	struct emc2103_data *data = emc2103_update_device(dev);
290	int rpm = 0;
291	if (data->fan_tach != 0)
292		rpm = (FAN_RPM_FACTOR * data->fan_multiplier) / data->fan_tach;
293	return sprintf(buf, "%d\n", rpm);
294}
295
296static ssize_t
297show_fan_div(struct device *dev, struct device_attribute *da, char *buf)
298{
299	struct emc2103_data *data = emc2103_update_device(dev);
300	int fan_div = 8 / data->fan_multiplier;
301	return sprintf(buf, "%d\n", fan_div);
302}
303
304/*
305 * Note: we also update the fan target here, because its value is
306 * determined in part by the fan clock divider.  This follows the principle
307 * of least surprise; the user doesn't expect the fan target to change just
308 * because the divider changed.
309 */
310static ssize_t set_fan_div(struct device *dev, struct device_attribute *da,
311			   const char *buf, size_t count)
312{
313	struct emc2103_data *data = emc2103_update_device(dev);
314	struct i2c_client *client = data->client;
315	int new_range_bits, old_div = 8 / data->fan_multiplier;
316	long new_div;
317
318	int status = kstrtol(buf, 10, &new_div);
319	if (status < 0)
320		return status;
321
322	if (new_div == old_div) /* No change */
323		return count;
324
325	switch (new_div) {
326	case 1:
327		new_range_bits = 3;
328		break;
329	case 2:
330		new_range_bits = 2;
331		break;
332	case 4:
333		new_range_bits = 1;
334		break;
335	case 8:
336		new_range_bits = 0;
337		break;
338	default:
339		return -EINVAL;
340	}
341
342	mutex_lock(&data->update_lock);
343
344	status = i2c_smbus_read_byte_data(client, REG_FAN_CONF1);
345	if (status < 0) {
346		dev_dbg(&client->dev, "reg 0x%02x, err %d\n",
347			REG_FAN_CONF1, status);
348		mutex_unlock(&data->update_lock);
349		return status;
350	}
351	status &= 0x9F;
352	status |= (new_range_bits << 5);
353	i2c_smbus_write_byte_data(client, REG_FAN_CONF1, status);
354
355	data->fan_multiplier = 8 / new_div;
356
357	/* update fan target if high byte is not disabled */
358	if ((data->fan_target & 0x1fe0) != 0x1fe0) {
359		u16 new_target = (data->fan_target * old_div) / new_div;
360		data->fan_target = min(new_target, (u16)0x1fff);
361		write_fan_target_to_i2c(client, data->fan_target);
362	}
363
364	/* invalidate data to force re-read from hardware */
365	data->valid = false;
366
367	mutex_unlock(&data->update_lock);
368	return count;
369}
370
371static ssize_t
372show_fan_target(struct device *dev, struct device_attribute *da, char *buf)
373{
374	struct emc2103_data *data = emc2103_update_device(dev);
375	int rpm = 0;
376
377	/* high byte of 0xff indicates disabled so return 0 */
378	if ((data->fan_target != 0) && ((data->fan_target & 0x1fe0) != 0x1fe0))
379		rpm = (FAN_RPM_FACTOR * data->fan_multiplier)
380			/ data->fan_target;
381
382	return sprintf(buf, "%d\n", rpm);
383}
384
385static ssize_t set_fan_target(struct device *dev, struct device_attribute *da,
386			      const char *buf, size_t count)
387{
388	struct emc2103_data *data = emc2103_update_device(dev);
389	struct i2c_client *client = data->client;
390	unsigned long rpm_target;
391
392	int result = kstrtoul(buf, 10, &rpm_target);
393	if (result < 0)
394		return result;
395
396	/* Datasheet states 16384 as maximum RPM target (table 3.2) */
397	rpm_target = clamp_val(rpm_target, 0, 16384);
398
399	mutex_lock(&data->update_lock);
400
401	if (rpm_target == 0)
402		data->fan_target = 0x1fff;
403	else
404		data->fan_target = clamp_val(
405			(FAN_RPM_FACTOR * data->fan_multiplier) / rpm_target,
406			0, 0x1fff);
407
408	write_fan_target_to_i2c(client, data->fan_target);
409
410	mutex_unlock(&data->update_lock);
411	return count;
412}
413
414static ssize_t
415show_fan_fault(struct device *dev, struct device_attribute *da, char *buf)
416{
417	struct emc2103_data *data = emc2103_update_device(dev);
418	bool fault = ((data->fan_tach & 0x1fe0) == 0x1fe0);
419	return sprintf(buf, "%d\n", fault ? 1 : 0);
420}
421
422static ssize_t
423show_pwm_enable(struct device *dev, struct device_attribute *da, char *buf)
424{
425	struct emc2103_data *data = emc2103_update_device(dev);
426	return sprintf(buf, "%d\n", data->fan_rpm_control ? 3 : 0);
427}
428
429static ssize_t set_pwm_enable(struct device *dev, struct device_attribute *da,
430			      const char *buf, size_t count)
431{
432	struct emc2103_data *data = dev_get_drvdata(dev);
433	struct i2c_client *client = data->client;
434	long new_value;
435	u8 conf_reg;
436
437	int result = kstrtol(buf, 10, &new_value);
438	if (result < 0)
439		return result;
440
441	mutex_lock(&data->update_lock);
442	switch (new_value) {
443	case 0:
444		data->fan_rpm_control = false;
445		break;
446	case 3:
447		data->fan_rpm_control = true;
448		break;
449	default:
450		count = -EINVAL;
451		goto err;
452	}
453
454	result = read_u8_from_i2c(client, REG_FAN_CONF1, &conf_reg);
455	if (result) {
456		count = result;
457		goto err;
458	}
459
460	if (data->fan_rpm_control)
461		conf_reg |= 0x80;
462	else
463		conf_reg &= ~0x80;
464
465	i2c_smbus_write_byte_data(client, REG_FAN_CONF1, conf_reg);
466err:
467	mutex_unlock(&data->update_lock);
468	return count;
469}
470
471static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0);
472static SENSOR_DEVICE_ATTR(temp1_min, S_IRUGO | S_IWUSR, show_temp_min,
473	set_temp_min, 0);
474static SENSOR_DEVICE_ATTR(temp1_max, S_IRUGO | S_IWUSR, show_temp_max,
475	set_temp_max, 0);
476static SENSOR_DEVICE_ATTR(temp1_fault, S_IRUGO, show_temp_fault, NULL, 0);
477static SENSOR_DEVICE_ATTR(temp1_min_alarm, S_IRUGO, show_temp_min_alarm,
478	NULL, 0);
479static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_temp_max_alarm,
480	NULL, 0);
481
482static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_temp, NULL, 1);
483static SENSOR_DEVICE_ATTR(temp2_min, S_IRUGO | S_IWUSR, show_temp_min,
484	set_temp_min, 1);
485static SENSOR_DEVICE_ATTR(temp2_max, S_IRUGO | S_IWUSR, show_temp_max,
486	set_temp_max, 1);
487static SENSOR_DEVICE_ATTR(temp2_fault, S_IRUGO, show_temp_fault, NULL, 1);
488static SENSOR_DEVICE_ATTR(temp2_min_alarm, S_IRUGO, show_temp_min_alarm,
489	NULL, 1);
490static SENSOR_DEVICE_ATTR(temp2_max_alarm, S_IRUGO, show_temp_max_alarm,
491	NULL, 1);
492
493static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, show_temp, NULL, 2);
494static SENSOR_DEVICE_ATTR(temp3_min, S_IRUGO | S_IWUSR, show_temp_min,
495	set_temp_min, 2);
496static SENSOR_DEVICE_ATTR(temp3_max, S_IRUGO | S_IWUSR, show_temp_max,
497	set_temp_max, 2);
498static SENSOR_DEVICE_ATTR(temp3_fault, S_IRUGO, show_temp_fault, NULL, 2);
499static SENSOR_DEVICE_ATTR(temp3_min_alarm, S_IRUGO, show_temp_min_alarm,
500	NULL, 2);
501static SENSOR_DEVICE_ATTR(temp3_max_alarm, S_IRUGO, show_temp_max_alarm,
502	NULL, 2);
503
504static SENSOR_DEVICE_ATTR(temp4_input, S_IRUGO, show_temp, NULL, 3);
505static SENSOR_DEVICE_ATTR(temp4_min, S_IRUGO | S_IWUSR, show_temp_min,
506	set_temp_min, 3);
507static SENSOR_DEVICE_ATTR(temp4_max, S_IRUGO | S_IWUSR, show_temp_max,
508	set_temp_max, 3);
509static SENSOR_DEVICE_ATTR(temp4_fault, S_IRUGO, show_temp_fault, NULL, 3);
510static SENSOR_DEVICE_ATTR(temp4_min_alarm, S_IRUGO, show_temp_min_alarm,
511	NULL, 3);
512static SENSOR_DEVICE_ATTR(temp4_max_alarm, S_IRUGO, show_temp_max_alarm,
513	NULL, 3);
514
515static DEVICE_ATTR(fan1_input, S_IRUGO, show_fan, NULL);
516static DEVICE_ATTR(fan1_div, S_IRUGO | S_IWUSR, show_fan_div, set_fan_div);
517static DEVICE_ATTR(fan1_target, S_IRUGO | S_IWUSR, show_fan_target,
518	set_fan_target);
519static DEVICE_ATTR(fan1_fault, S_IRUGO, show_fan_fault, NULL);
520
521static DEVICE_ATTR(pwm1_enable, S_IRUGO | S_IWUSR, show_pwm_enable,
522	set_pwm_enable);
523
524/* sensors present on all models */
525static struct attribute *emc2103_attributes[] = {
526	&sensor_dev_attr_temp1_input.dev_attr.attr,
527	&sensor_dev_attr_temp1_min.dev_attr.attr,
528	&sensor_dev_attr_temp1_max.dev_attr.attr,
529	&sensor_dev_attr_temp1_fault.dev_attr.attr,
530	&sensor_dev_attr_temp1_min_alarm.dev_attr.attr,
531	&sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
532	&sensor_dev_attr_temp2_input.dev_attr.attr,
533	&sensor_dev_attr_temp2_min.dev_attr.attr,
534	&sensor_dev_attr_temp2_max.dev_attr.attr,
535	&sensor_dev_attr_temp2_fault.dev_attr.attr,
536	&sensor_dev_attr_temp2_min_alarm.dev_attr.attr,
537	&sensor_dev_attr_temp2_max_alarm.dev_attr.attr,
538	&dev_attr_fan1_input.attr,
539	&dev_attr_fan1_div.attr,
540	&dev_attr_fan1_target.attr,
541	&dev_attr_fan1_fault.attr,
542	&dev_attr_pwm1_enable.attr,
543	NULL
544};
545
546/* extra temperature sensors only present on 2103-2 and 2103-4 */
547static struct attribute *emc2103_attributes_temp3[] = {
548	&sensor_dev_attr_temp3_input.dev_attr.attr,
549	&sensor_dev_attr_temp3_min.dev_attr.attr,
550	&sensor_dev_attr_temp3_max.dev_attr.attr,
551	&sensor_dev_attr_temp3_fault.dev_attr.attr,
552	&sensor_dev_attr_temp3_min_alarm.dev_attr.attr,
553	&sensor_dev_attr_temp3_max_alarm.dev_attr.attr,
554	NULL
555};
556
557/* extra temperature sensors only present on 2103-2 and 2103-4 in APD mode */
558static struct attribute *emc2103_attributes_temp4[] = {
559	&sensor_dev_attr_temp4_input.dev_attr.attr,
560	&sensor_dev_attr_temp4_min.dev_attr.attr,
561	&sensor_dev_attr_temp4_max.dev_attr.attr,
562	&sensor_dev_attr_temp4_fault.dev_attr.attr,
563	&sensor_dev_attr_temp4_min_alarm.dev_attr.attr,
564	&sensor_dev_attr_temp4_max_alarm.dev_attr.attr,
565	NULL
566};
567
568static const struct attribute_group emc2103_group = {
569	.attrs = emc2103_attributes,
570};
571
572static const struct attribute_group emc2103_temp3_group = {
573	.attrs = emc2103_attributes_temp3,
574};
575
576static const struct attribute_group emc2103_temp4_group = {
577	.attrs = emc2103_attributes_temp4,
578};
579
580static int
581emc2103_probe(struct i2c_client *client, const struct i2c_device_id *id)
582{
583	struct emc2103_data *data;
584	struct device *hwmon_dev;
585	int status, idx = 0;
586
587	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
588		return -EIO;
589
590	data = devm_kzalloc(&client->dev, sizeof(struct emc2103_data),
591			    GFP_KERNEL);
592	if (!data)
593		return -ENOMEM;
594
595	i2c_set_clientdata(client, data);
596	data->client = client;
597	mutex_init(&data->update_lock);
598
599	/* 2103-2 and 2103-4 have 3 external diodes, 2103-1 has 1 */
600	status = i2c_smbus_read_byte_data(client, REG_PRODUCT_ID);
601	if (status == 0x24) {
602		/* 2103-1 only has 1 external diode */
603		data->temp_count = 2;
604	} else {
605		/* 2103-2 and 2103-4 have 3 or 4 external diodes */
606		status = i2c_smbus_read_byte_data(client, REG_CONF1);
607		if (status < 0) {
608			dev_dbg(&client->dev, "reg 0x%02x, err %d\n", REG_CONF1,
609				status);
610			return status;
611		}
612
613		/* detect current state of hardware */
614		data->temp_count = (status & 0x01) ? 4 : 3;
615
616		/* force APD state if module parameter is set */
617		if (apd == 0) {
618			/* force APD mode off */
619			data->temp_count = 3;
620			status &= ~(0x01);
621			i2c_smbus_write_byte_data(client, REG_CONF1, status);
622		} else if (apd == 1) {
623			/* force APD mode on */
624			data->temp_count = 4;
625			status |= 0x01;
626			i2c_smbus_write_byte_data(client, REG_CONF1, status);
627		}
628	}
629
630	/* sysfs hooks */
631	data->groups[idx++] = &emc2103_group;
632	if (data->temp_count >= 3)
633		data->groups[idx++] = &emc2103_temp3_group;
634	if (data->temp_count == 4)
635		data->groups[idx++] = &emc2103_temp4_group;
636
637	hwmon_dev = devm_hwmon_device_register_with_groups(&client->dev,
638							   client->name, data,
639							   data->groups);
640	if (IS_ERR(hwmon_dev))
641		return PTR_ERR(hwmon_dev);
642
643	dev_info(&client->dev, "%s: sensor '%s'\n",
644		 dev_name(hwmon_dev), client->name);
645
646	return 0;
647}
648
649static const struct i2c_device_id emc2103_ids[] = {
650	{ "emc2103", 0, },
651	{ /* LIST END */ }
652};
653MODULE_DEVICE_TABLE(i2c, emc2103_ids);
654
655/* Return 0 if detection is successful, -ENODEV otherwise */
656static int
657emc2103_detect(struct i2c_client *new_client, struct i2c_board_info *info)
658{
659	struct i2c_adapter *adapter = new_client->adapter;
660	int manufacturer, product;
661
662	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
663		return -ENODEV;
664
665	manufacturer = i2c_smbus_read_byte_data(new_client, REG_MFG_ID);
666	if (manufacturer != 0x5D)
667		return -ENODEV;
668
669	product = i2c_smbus_read_byte_data(new_client, REG_PRODUCT_ID);
670	if ((product != 0x24) && (product != 0x26))
671		return -ENODEV;
672
673	strlcpy(info->type, "emc2103", I2C_NAME_SIZE);
674
675	return 0;
676}
677
678static struct i2c_driver emc2103_driver = {
679	.class		= I2C_CLASS_HWMON,
680	.driver = {
681		.name	= "emc2103",
682	},
683	.probe		= emc2103_probe,
684	.id_table	= emc2103_ids,
685	.detect		= emc2103_detect,
686	.address_list	= normal_i2c,
687};
688
689module_i2c_driver(emc2103_driver);
690
691MODULE_AUTHOR("Steve Glendinning <steve.glendinning@shawell.net>");
692MODULE_DESCRIPTION("SMSC EMC2103 hwmon driver");
693MODULE_LICENSE("GPL");
694