1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  Driver for the ADT7411 (I2C/SPI 8 channel 10 bit ADC & temperature-sensor)
4  *
5  *  Copyright (C) 2008, 2010 Pengutronix
6  *
7  *  TODO: SPI, use power-down mode for suspend?, interrupt handling?
8  */
9 
10 #include <linux/kernel.h>
11 #include <linux/module.h>
12 #include <linux/init.h>
13 #include <linux/err.h>
14 #include <linux/mutex.h>
15 #include <linux/jiffies.h>
16 #include <linux/i2c.h>
17 #include <linux/hwmon.h>
18 #include <linux/hwmon-sysfs.h>
19 #include <linux/slab.h>
20 
21 #define ADT7411_REG_STAT_1			0x00
22 #define ADT7411_STAT_1_INT_TEMP_HIGH		BIT(0)
23 #define ADT7411_STAT_1_INT_TEMP_LOW		BIT(1)
24 #define ADT7411_STAT_1_EXT_TEMP_HIGH_AIN1	BIT(2)
25 #define ADT7411_STAT_1_EXT_TEMP_LOW		BIT(3)
26 #define ADT7411_STAT_1_EXT_TEMP_FAULT		BIT(4)
27 #define ADT7411_STAT_1_AIN2			BIT(5)
28 #define ADT7411_STAT_1_AIN3			BIT(6)
29 #define ADT7411_STAT_1_AIN4			BIT(7)
30 #define ADT7411_REG_STAT_2			0x01
31 #define ADT7411_STAT_2_AIN5			BIT(0)
32 #define ADT7411_STAT_2_AIN6			BIT(1)
33 #define ADT7411_STAT_2_AIN7			BIT(2)
34 #define ADT7411_STAT_2_AIN8			BIT(3)
35 #define ADT7411_STAT_2_VDD			BIT(4)
36 #define ADT7411_REG_INT_TEMP_VDD_LSB		0x03
37 #define ADT7411_REG_EXT_TEMP_AIN14_LSB		0x04
38 #define ADT7411_REG_VDD_MSB			0x06
39 #define ADT7411_REG_INT_TEMP_MSB		0x07
40 #define ADT7411_REG_EXT_TEMP_AIN1_MSB		0x08
41 
42 #define ADT7411_REG_CFG1			0x18
43 #define ADT7411_CFG1_START_MONITOR		BIT(0)
44 #define ADT7411_CFG1_RESERVED_BIT1		BIT(1)
45 #define ADT7411_CFG1_EXT_TDM			BIT(2)
46 #define ADT7411_CFG1_RESERVED_BIT3		BIT(3)
47 
48 #define ADT7411_REG_CFG2			0x19
49 #define ADT7411_CFG2_DISABLE_AVG		BIT(5)
50 
51 #define ADT7411_REG_CFG3			0x1a
52 #define ADT7411_CFG3_ADC_CLK_225		BIT(0)
53 #define ADT7411_CFG3_RESERVED_BIT1		BIT(1)
54 #define ADT7411_CFG3_RESERVED_BIT2		BIT(2)
55 #define ADT7411_CFG3_RESERVED_BIT3		BIT(3)
56 #define ADT7411_CFG3_REF_VDD			BIT(4)
57 
58 #define ADT7411_REG_VDD_HIGH			0x23
59 #define ADT7411_REG_VDD_LOW			0x24
60 #define ADT7411_REG_TEMP_HIGH(nr)		(0x25 + 2 * (nr))
61 #define ADT7411_REG_TEMP_LOW(nr)		(0x26 + 2 * (nr))
62 #define ADT7411_REG_IN_HIGH(nr)		((nr) > 1 \
63 						  ? 0x2b + 2 * ((nr)-2) \
64 						  : 0x27)
65 #define ADT7411_REG_IN_LOW(nr)			((nr) > 1 \
66 						  ? 0x2c + 2 * ((nr)-2) \
67 						  : 0x28)
68 
69 #define ADT7411_REG_DEVICE_ID			0x4d
70 #define ADT7411_REG_MANUFACTURER_ID		0x4e
71 
72 #define ADT7411_DEVICE_ID			0x2
73 #define ADT7411_MANUFACTURER_ID			0x41
74 
75 static const unsigned short normal_i2c[] = { 0x48, 0x4a, 0x4b, I2C_CLIENT_END };
76 
77 static const u8 adt7411_in_alarm_reg[] = {
78 	ADT7411_REG_STAT_2,
79 	ADT7411_REG_STAT_1,
80 	ADT7411_REG_STAT_1,
81 	ADT7411_REG_STAT_1,
82 	ADT7411_REG_STAT_1,
83 	ADT7411_REG_STAT_2,
84 	ADT7411_REG_STAT_2,
85 	ADT7411_REG_STAT_2,
86 	ADT7411_REG_STAT_2,
87 };
88 
89 static const u8 adt7411_in_alarm_bits[] = {
90 	ADT7411_STAT_2_VDD,
91 	ADT7411_STAT_1_EXT_TEMP_HIGH_AIN1,
92 	ADT7411_STAT_1_AIN2,
93 	ADT7411_STAT_1_AIN3,
94 	ADT7411_STAT_1_AIN4,
95 	ADT7411_STAT_2_AIN5,
96 	ADT7411_STAT_2_AIN6,
97 	ADT7411_STAT_2_AIN7,
98 	ADT7411_STAT_2_AIN8,
99 };
100 
101 struct adt7411_data {
102 	struct mutex device_lock;	/* for "atomic" device accesses */
103 	struct mutex update_lock;
104 	unsigned long next_update;
105 	long vref_cached;
106 	struct i2c_client *client;
107 	bool use_ext_temp;
108 };
109 
110 /*
111  * When reading a register containing (up to 4) lsb, all associated
112  * msb-registers get locked by the hardware. After _one_ of those msb is read,
113  * _all_ are unlocked. In order to use this locking correctly, reading lsb/msb
114  * is protected here with a mutex, too.
115  */
adt7411_read_10_bit(struct i2c_client * client,u8 lsb_reg,u8 msb_reg,u8 lsb_shift)116 static int adt7411_read_10_bit(struct i2c_client *client, u8 lsb_reg,
117 				u8 msb_reg, u8 lsb_shift)
118 {
119 	struct adt7411_data *data = i2c_get_clientdata(client);
120 	int val, tmp;
121 
122 	mutex_lock(&data->device_lock);
123 
124 	val = i2c_smbus_read_byte_data(client, lsb_reg);
125 	if (val < 0)
126 		goto exit_unlock;
127 
128 	tmp = (val >> lsb_shift) & 3;
129 	val = i2c_smbus_read_byte_data(client, msb_reg);
130 
131 	if (val >= 0)
132 		val = (val << 2) | tmp;
133 
134  exit_unlock:
135 	mutex_unlock(&data->device_lock);
136 
137 	return val;
138 }
139 
adt7411_modify_bit(struct i2c_client * client,u8 reg,u8 bit,bool flag)140 static int adt7411_modify_bit(struct i2c_client *client, u8 reg, u8 bit,
141 				bool flag)
142 {
143 	struct adt7411_data *data = i2c_get_clientdata(client);
144 	int ret, val;
145 
146 	mutex_lock(&data->device_lock);
147 
148 	ret = i2c_smbus_read_byte_data(client, reg);
149 	if (ret < 0)
150 		goto exit_unlock;
151 
152 	if (flag)
153 		val = ret | bit;
154 	else
155 		val = ret & ~bit;
156 
157 	ret = i2c_smbus_write_byte_data(client, reg, val);
158 
159  exit_unlock:
160 	mutex_unlock(&data->device_lock);
161 	return ret;
162 }
163 
adt7411_show_bit(struct device * dev,struct device_attribute * attr,char * buf)164 static ssize_t adt7411_show_bit(struct device *dev,
165 				struct device_attribute *attr, char *buf)
166 {
167 	struct sensor_device_attribute_2 *attr2 = to_sensor_dev_attr_2(attr);
168 	struct adt7411_data *data = dev_get_drvdata(dev);
169 	struct i2c_client *client = data->client;
170 	int ret = i2c_smbus_read_byte_data(client, attr2->index);
171 
172 	return ret < 0 ? ret : sprintf(buf, "%u\n", !!(ret & attr2->nr));
173 }
174 
adt7411_set_bit(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)175 static ssize_t adt7411_set_bit(struct device *dev,
176 			       struct device_attribute *attr, const char *buf,
177 			       size_t count)
178 {
179 	struct sensor_device_attribute_2 *s_attr2 = to_sensor_dev_attr_2(attr);
180 	struct adt7411_data *data = dev_get_drvdata(dev);
181 	struct i2c_client *client = data->client;
182 	int ret;
183 	unsigned long flag;
184 
185 	ret = kstrtoul(buf, 0, &flag);
186 	if (ret || flag > 1)
187 		return -EINVAL;
188 
189 	ret = adt7411_modify_bit(client, s_attr2->index, s_attr2->nr, flag);
190 
191 	/* force update */
192 	mutex_lock(&data->update_lock);
193 	data->next_update = jiffies;
194 	mutex_unlock(&data->update_lock);
195 
196 	return ret < 0 ? ret : count;
197 }
198 
199 #define ADT7411_BIT_ATTR(__name, __reg, __bit) \
200 	SENSOR_DEVICE_ATTR_2(__name, S_IRUGO | S_IWUSR, adt7411_show_bit, \
201 	adt7411_set_bit, __bit, __reg)
202 
203 static ADT7411_BIT_ATTR(no_average, ADT7411_REG_CFG2, ADT7411_CFG2_DISABLE_AVG);
204 static ADT7411_BIT_ATTR(fast_sampling, ADT7411_REG_CFG3, ADT7411_CFG3_ADC_CLK_225);
205 static ADT7411_BIT_ATTR(adc_ref_vdd, ADT7411_REG_CFG3, ADT7411_CFG3_REF_VDD);
206 
207 static struct attribute *adt7411_attrs[] = {
208 	&sensor_dev_attr_no_average.dev_attr.attr,
209 	&sensor_dev_attr_fast_sampling.dev_attr.attr,
210 	&sensor_dev_attr_adc_ref_vdd.dev_attr.attr,
211 	NULL
212 };
213 ATTRIBUTE_GROUPS(adt7411);
214 
adt7411_read_in_alarm(struct device * dev,int channel,long * val)215 static int adt7411_read_in_alarm(struct device *dev, int channel, long *val)
216 {
217 	struct adt7411_data *data = dev_get_drvdata(dev);
218 	struct i2c_client *client = data->client;
219 	int ret;
220 
221 	ret = i2c_smbus_read_byte_data(client, adt7411_in_alarm_reg[channel]);
222 	if (ret < 0)
223 		return ret;
224 	*val = !!(ret & adt7411_in_alarm_bits[channel]);
225 	return 0;
226 }
227 
adt7411_read_in_vdd(struct device * dev,u32 attr,long * val)228 static int adt7411_read_in_vdd(struct device *dev, u32 attr, long *val)
229 {
230 	struct adt7411_data *data = dev_get_drvdata(dev);
231 	struct i2c_client *client = data->client;
232 	int ret;
233 
234 	switch (attr) {
235 	case hwmon_in_input:
236 		ret = adt7411_read_10_bit(client, ADT7411_REG_INT_TEMP_VDD_LSB,
237 					  ADT7411_REG_VDD_MSB, 2);
238 		if (ret < 0)
239 			return ret;
240 		*val = ret * 7000 / 1024;
241 		return 0;
242 	case hwmon_in_min:
243 		ret = i2c_smbus_read_byte_data(client, ADT7411_REG_VDD_LOW);
244 		if (ret < 0)
245 			return ret;
246 		*val = ret * 7000 / 256;
247 		return 0;
248 	case hwmon_in_max:
249 		ret = i2c_smbus_read_byte_data(client, ADT7411_REG_VDD_HIGH);
250 		if (ret < 0)
251 			return ret;
252 		*val = ret * 7000 / 256;
253 		return 0;
254 	case hwmon_in_alarm:
255 		return adt7411_read_in_alarm(dev, 0, val);
256 	default:
257 		return -EOPNOTSUPP;
258 	}
259 }
260 
adt7411_update_vref(struct device * dev)261 static int adt7411_update_vref(struct device *dev)
262 {
263 	struct adt7411_data *data = dev_get_drvdata(dev);
264 	struct i2c_client *client = data->client;
265 	int val;
266 
267 	if (time_after_eq(jiffies, data->next_update)) {
268 		val = i2c_smbus_read_byte_data(client, ADT7411_REG_CFG3);
269 		if (val < 0)
270 			return val;
271 
272 		if (val & ADT7411_CFG3_REF_VDD) {
273 			val = adt7411_read_in_vdd(dev, hwmon_in_input,
274 						  &data->vref_cached);
275 			if (val < 0)
276 				return val;
277 		} else {
278 			data->vref_cached = 2250;
279 		}
280 
281 		data->next_update = jiffies + HZ;
282 	}
283 
284 	return 0;
285 }
286 
adt7411_read_in_chan(struct device * dev,u32 attr,int channel,long * val)287 static int adt7411_read_in_chan(struct device *dev, u32 attr, int channel,
288 				long *val)
289 {
290 	struct adt7411_data *data = dev_get_drvdata(dev);
291 	struct i2c_client *client = data->client;
292 
293 	int ret;
294 	int reg, lsb_reg, lsb_shift;
295 	int nr = channel - 1;
296 
297 	mutex_lock(&data->update_lock);
298 	ret = adt7411_update_vref(dev);
299 	if (ret < 0)
300 		goto exit_unlock;
301 
302 	switch (attr) {
303 	case hwmon_in_input:
304 		lsb_reg = ADT7411_REG_EXT_TEMP_AIN14_LSB + (nr >> 2);
305 		lsb_shift = 2 * (nr & 0x03);
306 		ret = adt7411_read_10_bit(client, lsb_reg,
307 					  ADT7411_REG_EXT_TEMP_AIN1_MSB + nr,
308 					  lsb_shift);
309 		if (ret < 0)
310 			goto exit_unlock;
311 		*val = ret * data->vref_cached / 1024;
312 		ret = 0;
313 		break;
314 	case hwmon_in_min:
315 	case hwmon_in_max:
316 		reg = (attr == hwmon_in_min)
317 			? ADT7411_REG_IN_LOW(channel)
318 			: ADT7411_REG_IN_HIGH(channel);
319 		ret = i2c_smbus_read_byte_data(client, reg);
320 		if (ret < 0)
321 			goto exit_unlock;
322 		*val = ret * data->vref_cached / 256;
323 		ret = 0;
324 		break;
325 	case hwmon_in_alarm:
326 		ret = adt7411_read_in_alarm(dev, channel, val);
327 		break;
328 	default:
329 		ret = -EOPNOTSUPP;
330 		break;
331 	}
332  exit_unlock:
333 	mutex_unlock(&data->update_lock);
334 	return ret;
335 }
336 
adt7411_read_in(struct device * dev,u32 attr,int channel,long * val)337 static int adt7411_read_in(struct device *dev, u32 attr, int channel,
338 			   long *val)
339 {
340 	if (channel == 0)
341 		return adt7411_read_in_vdd(dev, attr, val);
342 	else
343 		return adt7411_read_in_chan(dev, attr, channel, val);
344 }
345 
346 
adt7411_read_temp_alarm(struct device * dev,u32 attr,int channel,long * val)347 static int adt7411_read_temp_alarm(struct device *dev, u32 attr, int channel,
348 				   long *val)
349 {
350 	struct adt7411_data *data = dev_get_drvdata(dev);
351 	struct i2c_client *client = data->client;
352 	int ret, bit;
353 
354 	ret = i2c_smbus_read_byte_data(client, ADT7411_REG_STAT_1);
355 	if (ret < 0)
356 		return ret;
357 
358 	switch (attr) {
359 	case hwmon_temp_min_alarm:
360 		bit = channel ? ADT7411_STAT_1_EXT_TEMP_LOW
361 			      : ADT7411_STAT_1_INT_TEMP_LOW;
362 		break;
363 	case hwmon_temp_max_alarm:
364 		bit = channel ? ADT7411_STAT_1_EXT_TEMP_HIGH_AIN1
365 			      : ADT7411_STAT_1_INT_TEMP_HIGH;
366 		break;
367 	case hwmon_temp_fault:
368 		bit = ADT7411_STAT_1_EXT_TEMP_FAULT;
369 		break;
370 	default:
371 		return -EOPNOTSUPP;
372 	}
373 
374 	*val = !!(ret & bit);
375 	return 0;
376 }
377 
adt7411_read_temp(struct device * dev,u32 attr,int channel,long * val)378 static int adt7411_read_temp(struct device *dev, u32 attr, int channel,
379 			     long *val)
380 {
381 	struct adt7411_data *data = dev_get_drvdata(dev);
382 	struct i2c_client *client = data->client;
383 	int ret, reg, regl, regh;
384 
385 	switch (attr) {
386 	case hwmon_temp_input:
387 		regl = channel ? ADT7411_REG_EXT_TEMP_AIN14_LSB :
388 				 ADT7411_REG_INT_TEMP_VDD_LSB;
389 		regh = channel ? ADT7411_REG_EXT_TEMP_AIN1_MSB :
390 				 ADT7411_REG_INT_TEMP_MSB;
391 		ret = adt7411_read_10_bit(client, regl, regh, 0);
392 		if (ret < 0)
393 			return ret;
394 		ret = ret & 0x200 ? ret - 0x400 : ret; /* 10 bit signed */
395 		*val = ret * 250;
396 		return 0;
397 	case hwmon_temp_min:
398 	case hwmon_temp_max:
399 		reg = (attr == hwmon_temp_min)
400 			? ADT7411_REG_TEMP_LOW(channel)
401 			: ADT7411_REG_TEMP_HIGH(channel);
402 		ret = i2c_smbus_read_byte_data(client, reg);
403 		if (ret < 0)
404 			return ret;
405 		ret = ret & 0x80 ? ret - 0x100 : ret; /* 8 bit signed */
406 		*val = ret * 1000;
407 		return 0;
408 	case hwmon_temp_min_alarm:
409 	case hwmon_temp_max_alarm:
410 	case hwmon_temp_fault:
411 		return adt7411_read_temp_alarm(dev, attr, channel, val);
412 	default:
413 		return -EOPNOTSUPP;
414 	}
415 }
416 
adt7411_read(struct device * dev,enum hwmon_sensor_types type,u32 attr,int channel,long * val)417 static int adt7411_read(struct device *dev, enum hwmon_sensor_types type,
418 			u32 attr, int channel, long *val)
419 {
420 	switch (type) {
421 	case hwmon_in:
422 		return adt7411_read_in(dev, attr, channel, val);
423 	case hwmon_temp:
424 		return adt7411_read_temp(dev, attr, channel, val);
425 	default:
426 		return -EOPNOTSUPP;
427 	}
428 }
429 
adt7411_write_in_vdd(struct device * dev,u32 attr,long val)430 static int adt7411_write_in_vdd(struct device *dev, u32 attr, long val)
431 {
432 	struct adt7411_data *data = dev_get_drvdata(dev);
433 	struct i2c_client *client = data->client;
434 	int reg;
435 
436 	val = clamp_val(val, 0, 255 * 7000 / 256);
437 	val = DIV_ROUND_CLOSEST(val * 256, 7000);
438 
439 	switch (attr) {
440 	case hwmon_in_min:
441 		reg = ADT7411_REG_VDD_LOW;
442 		break;
443 	case hwmon_in_max:
444 		reg = ADT7411_REG_VDD_HIGH;
445 		break;
446 	default:
447 		return -EOPNOTSUPP;
448 	}
449 
450 	return i2c_smbus_write_byte_data(client, reg, val);
451 }
452 
adt7411_write_in_chan(struct device * dev,u32 attr,int channel,long val)453 static int adt7411_write_in_chan(struct device *dev, u32 attr, int channel,
454 				 long val)
455 {
456 	struct adt7411_data *data = dev_get_drvdata(dev);
457 	struct i2c_client *client = data->client;
458 	int ret, reg;
459 
460 	mutex_lock(&data->update_lock);
461 	ret = adt7411_update_vref(dev);
462 	if (ret < 0)
463 		goto exit_unlock;
464 	val = clamp_val(val, 0, 255 * data->vref_cached / 256);
465 	val = DIV_ROUND_CLOSEST(val * 256, data->vref_cached);
466 
467 	switch (attr) {
468 	case hwmon_in_min:
469 		reg = ADT7411_REG_IN_LOW(channel);
470 		break;
471 	case hwmon_in_max:
472 		reg = ADT7411_REG_IN_HIGH(channel);
473 		break;
474 	default:
475 		ret = -EOPNOTSUPP;
476 		goto exit_unlock;
477 	}
478 
479 	ret = i2c_smbus_write_byte_data(client, reg, val);
480  exit_unlock:
481 	mutex_unlock(&data->update_lock);
482 	return ret;
483 }
484 
adt7411_write_in(struct device * dev,u32 attr,int channel,long val)485 static int adt7411_write_in(struct device *dev, u32 attr, int channel,
486 			    long val)
487 {
488 	if (channel == 0)
489 		return adt7411_write_in_vdd(dev, attr, val);
490 	else
491 		return adt7411_write_in_chan(dev, attr, channel, val);
492 }
493 
adt7411_write_temp(struct device * dev,u32 attr,int channel,long val)494 static int adt7411_write_temp(struct device *dev, u32 attr, int channel,
495 			      long val)
496 {
497 	struct adt7411_data *data = dev_get_drvdata(dev);
498 	struct i2c_client *client = data->client;
499 	int reg;
500 
501 	val = clamp_val(val, -128000, 127000);
502 	val = DIV_ROUND_CLOSEST(val, 1000);
503 
504 	switch (attr) {
505 	case hwmon_temp_min:
506 		reg = ADT7411_REG_TEMP_LOW(channel);
507 		break;
508 	case hwmon_temp_max:
509 		reg = ADT7411_REG_TEMP_HIGH(channel);
510 		break;
511 	default:
512 		return -EOPNOTSUPP;
513 	}
514 
515 	return i2c_smbus_write_byte_data(client, reg, val);
516 }
517 
adt7411_write(struct device * dev,enum hwmon_sensor_types type,u32 attr,int channel,long val)518 static int adt7411_write(struct device *dev, enum hwmon_sensor_types type,
519 			 u32 attr, int channel, long val)
520 {
521 	switch (type) {
522 	case hwmon_in:
523 		return adt7411_write_in(dev, attr, channel, val);
524 	case hwmon_temp:
525 		return adt7411_write_temp(dev, attr, channel, val);
526 	default:
527 		return -EOPNOTSUPP;
528 	}
529 }
530 
adt7411_is_visible(const void * _data,enum hwmon_sensor_types type,u32 attr,int channel)531 static umode_t adt7411_is_visible(const void *_data,
532 				  enum hwmon_sensor_types type,
533 				  u32 attr, int channel)
534 {
535 	const struct adt7411_data *data = _data;
536 	bool visible;
537 
538 	switch (type) {
539 	case hwmon_in:
540 		visible = channel == 0 || channel >= 3 || !data->use_ext_temp;
541 		switch (attr) {
542 		case hwmon_in_input:
543 		case hwmon_in_alarm:
544 			return visible ? S_IRUGO : 0;
545 		case hwmon_in_min:
546 		case hwmon_in_max:
547 			return visible ? S_IRUGO | S_IWUSR : 0;
548 		}
549 		break;
550 	case hwmon_temp:
551 		visible = channel == 0 || data->use_ext_temp;
552 		switch (attr) {
553 		case hwmon_temp_input:
554 		case hwmon_temp_min_alarm:
555 		case hwmon_temp_max_alarm:
556 		case hwmon_temp_fault:
557 			return visible ? S_IRUGO : 0;
558 		case hwmon_temp_min:
559 		case hwmon_temp_max:
560 			return visible ? S_IRUGO | S_IWUSR : 0;
561 		}
562 		break;
563 	default:
564 		break;
565 	}
566 	return 0;
567 }
568 
adt7411_detect(struct i2c_client * client,struct i2c_board_info * info)569 static int adt7411_detect(struct i2c_client *client,
570 			  struct i2c_board_info *info)
571 {
572 	int val;
573 
574 	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
575 		return -ENODEV;
576 
577 	val = i2c_smbus_read_byte_data(client, ADT7411_REG_MANUFACTURER_ID);
578 	if (val < 0 || val != ADT7411_MANUFACTURER_ID) {
579 		dev_dbg(&client->dev,
580 			"Wrong manufacturer ID. Got %d, expected %d\n",
581 			val, ADT7411_MANUFACTURER_ID);
582 		return -ENODEV;
583 	}
584 
585 	val = i2c_smbus_read_byte_data(client, ADT7411_REG_DEVICE_ID);
586 	if (val < 0 || val != ADT7411_DEVICE_ID) {
587 		dev_dbg(&client->dev,
588 			"Wrong device ID. Got %d, expected %d\n",
589 			val, ADT7411_DEVICE_ID);
590 		return -ENODEV;
591 	}
592 
593 	strlcpy(info->type, "adt7411", I2C_NAME_SIZE);
594 
595 	return 0;
596 }
597 
adt7411_init_device(struct adt7411_data * data)598 static int adt7411_init_device(struct adt7411_data *data)
599 {
600 	int ret;
601 	u8 val;
602 
603 	ret = i2c_smbus_read_byte_data(data->client, ADT7411_REG_CFG3);
604 	if (ret < 0)
605 		return ret;
606 
607 	/*
608 	 * We must only write zero to bit 1 and bit 2 and only one to bit 3
609 	 * according to the datasheet.
610 	 */
611 	val = ret;
612 	val &= ~(ADT7411_CFG3_RESERVED_BIT1 | ADT7411_CFG3_RESERVED_BIT2);
613 	val |= ADT7411_CFG3_RESERVED_BIT3;
614 
615 	ret = i2c_smbus_write_byte_data(data->client, ADT7411_REG_CFG3, val);
616 	if (ret < 0)
617 		return ret;
618 
619 	ret = i2c_smbus_read_byte_data(data->client, ADT7411_REG_CFG1);
620 	if (ret < 0)
621 		return ret;
622 
623 	data->use_ext_temp = ret & ADT7411_CFG1_EXT_TDM;
624 
625 	/*
626 	 * We must only write zero to bit 1 and only one to bit 3 according to
627 	 * the datasheet.
628 	 */
629 	val = ret;
630 	val &= ~ADT7411_CFG1_RESERVED_BIT1;
631 	val |= ADT7411_CFG1_RESERVED_BIT3;
632 
633 	/* enable monitoring */
634 	val |= ADT7411_CFG1_START_MONITOR;
635 
636 	return i2c_smbus_write_byte_data(data->client, ADT7411_REG_CFG1, val);
637 }
638 
639 static const struct hwmon_channel_info *adt7411_info[] = {
640 	HWMON_CHANNEL_INFO(in,
641 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX | HWMON_I_ALARM,
642 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX | HWMON_I_ALARM,
643 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX | HWMON_I_ALARM,
644 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX | HWMON_I_ALARM,
645 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX | HWMON_I_ALARM,
646 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX | HWMON_I_ALARM,
647 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX | HWMON_I_ALARM,
648 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX | HWMON_I_ALARM,
649 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX | HWMON_I_ALARM),
650 	HWMON_CHANNEL_INFO(temp,
651 			   HWMON_T_INPUT | HWMON_T_MIN | HWMON_T_MIN_ALARM |
652 			   HWMON_T_MAX | HWMON_T_MAX_ALARM,
653 			   HWMON_T_INPUT | HWMON_T_MIN | HWMON_T_MIN_ALARM |
654 			   HWMON_T_MAX | HWMON_T_MAX_ALARM | HWMON_T_FAULT),
655 	NULL
656 };
657 
658 static const struct hwmon_ops adt7411_hwmon_ops = {
659 	.is_visible = adt7411_is_visible,
660 	.read = adt7411_read,
661 	.write = adt7411_write,
662 };
663 
664 static const struct hwmon_chip_info adt7411_chip_info = {
665 	.ops = &adt7411_hwmon_ops,
666 	.info = adt7411_info,
667 };
668 
adt7411_probe(struct i2c_client * client)669 static int adt7411_probe(struct i2c_client *client)
670 {
671 	struct device *dev = &client->dev;
672 	struct adt7411_data *data;
673 	struct device *hwmon_dev;
674 	int ret;
675 
676 	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
677 	if (!data)
678 		return -ENOMEM;
679 
680 	i2c_set_clientdata(client, data);
681 	data->client = client;
682 	mutex_init(&data->device_lock);
683 	mutex_init(&data->update_lock);
684 
685 	ret = adt7411_init_device(data);
686 	if (ret < 0)
687 		return ret;
688 
689 	/* force update on first occasion */
690 	data->next_update = jiffies;
691 
692 	hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
693 							 data,
694 							 &adt7411_chip_info,
695 							 adt7411_groups);
696 	return PTR_ERR_OR_ZERO(hwmon_dev);
697 }
698 
699 static const struct i2c_device_id adt7411_id[] = {
700 	{ "adt7411", 0 },
701 	{ }
702 };
703 MODULE_DEVICE_TABLE(i2c, adt7411_id);
704 
705 static struct i2c_driver adt7411_driver = {
706 	.driver		= {
707 		.name		= "adt7411",
708 	},
709 	.probe_new = adt7411_probe,
710 	.id_table = adt7411_id,
711 	.detect = adt7411_detect,
712 	.address_list = normal_i2c,
713 	.class = I2C_CLASS_HWMON,
714 };
715 
716 module_i2c_driver(adt7411_driver);
717 
718 MODULE_AUTHOR("Sascha Hauer, Wolfram Sang <kernel@pengutronix.de>");
719 MODULE_DESCRIPTION("ADT7411 driver");
720 MODULE_LICENSE("GPL v2");
721