summaryrefslogtreecommitdiff
path: root/drivers/hwmon/max1668.c
blob: 9f748973d6a371d62aa15ead2b38e4afc911b36e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Copyright (c) 2011 David George <david.george@ska.ac.za>
 *
 * based on adm1021.c
 * some credit to Christoph Scheurer, but largely a rewrite
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/jiffies.h>
#include <linux/i2c.h>
#include <linux/hwmon.h>
#include <linux/hwmon-sysfs.h>
#include <linux/err.h>
#include <linux/mutex.h>

/* Addresses to scan */
static const unsigned short max1668_addr_list[] = {
	0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b, 0x4c, 0x4d, 0x4e, I2C_CLIENT_END };

/* max1668 registers */

#define MAX1668_REG_TEMP(nr)	(nr)
#define MAX1668_REG_STAT1	0x05
#define MAX1668_REG_STAT2	0x06
#define MAX1668_REG_MAN_ID	0xfe
#define MAX1668_REG_DEV_ID	0xff

/* limits */

/* write high limits */
#define MAX1668_REG_LIMH_WR(nr)	(0x13 + 2 * (nr))
/* write low limits */
#define MAX1668_REG_LIML_WR(nr)	(0x14 + 2 * (nr))
/* read high limits */
#define MAX1668_REG_LIMH_RD(nr)	(0x08 + 2 * (nr))
/* read low limits */
#define MAX1668_REG_LIML_RD(nr)	(0x09 + 2 * (nr))

/* manufacturer and device ID Constants */
#define MAN_ID_MAXIM		0x4d
#define DEV_ID_MAX1668		0x3
#define DEV_ID_MAX1805		0x5
#define DEV_ID_MAX1989		0xb

/* read only mode module parameter */
static bool read_only;
module_param(read_only, bool, 0);
MODULE_PARM_DESC(read_only, "Don't set any values, read only mode");

enum chips { max1668, max1805, max1989 };

struct max1668_data {
	struct i2c_client *client;
	const struct attribute_group *groups[3];
	enum chips type;

	struct mutex update_lock;
	bool valid;		/* true if following fields are valid */
	unsigned long last_updated;	/* In jiffies */

	/* 1x local and 4x remote */
	s8 temp_max[5];
	s8 temp_min[5];
	s8 temp[5];
	u16 alarms;
};

static struct max1668_data *max1668_update_device(struct device *dev)
{
	struct max1668_data *data = dev_get_drvdata(dev);
	struct i2c_client *client = data->client;
	struct max1668_data *ret = data;
	s32 val;
	int i;

	mutex_lock(&data->update_lock);

	if (data->valid && !time_after(jiffies,
			data->last_updated + HZ + HZ / 2))
		goto abort;

	for (i = 0; i < 5; i++) {
		val = i2c_smbus_read_byte_data(client, MAX1668_REG_TEMP(i));
		if (unlikely(val < 0)) {
			ret = ERR_PTR(val);
			goto abort;
		}
		data->temp[i] = (s8) val;

		val = i2c_smbus_read_byte_data(client, MAX1668_REG_LIMH_RD(i));
		if (unlikely(val < 0)) {
			ret = ERR_PTR(val);
			goto abort;
		}
		data->temp_max[i] = (s8) val;

		val = i2c_smbus_read_byte_data(client, MAX1668_REG_LIML_RD(i));
		if (unlikely(val < 0)) {
			ret = ERR_PTR(val);
			goto abort;
		}
		data->temp_min[i] = (s8) val;
	}

	val = i2c_smbus_read_byte_data(client, MAX1668_REG_STAT1);
	if (unlikely(val < 0)) {
		ret = ERR_PTR(val);
		goto abort;
	}
	data->alarms = val << 8;

	val = i2c_smbus_read_byte_data(client, MAX1668_REG_STAT2);
	if (unlikely(val < 0)) {
		ret = ERR_PTR(val);
		goto abort;
	}
	data->alarms |= val;

	data->last_updated = jiffies;
	data->valid = true;
abort:
	mutex_unlock(&data->update_lock);

	return ret;
}

static ssize_t show_temp(struct device *dev,
			 struct device_attribute *devattr, char *buf)
{
	int index = to_sensor_dev_attr(devattr)->index;
	struct max1668_data *data = max1668_update_device(dev);

	if (IS_ERR(data))
		return PTR_ERR(data);

	return sprintf(buf, "%d\n", data->temp[index] * 1000);
}

static ssize_t show_temp_max(struct device *dev,
			     struct device_attribute *devattr, char *buf)
{
	int index = to_sensor_dev_attr(devattr)->index;
	struct max1668_data *data = max1668_update_device(dev);

	if (IS_ERR(data))
		return PTR_ERR(data);

	return sprintf(buf, "%d\n", data->temp_max[index] * 1000);
}

static ssize_t show_temp_min(struct device *dev,
			     struct device_attribute *devattr, char *buf)
{
	int index = to_sensor_dev_attr(devattr)->index;
	struct max1668_data *data = max1668_update_device(dev);

	if (IS_ERR(data))
		return PTR_ERR(data);

	return sprintf(buf, "%d\n", data->temp_min[index] * 1000);
}

static ssize_t show_alarm(struct device *dev, struct device_attribute *attr,
			  char *buf)
{
	int index = to_sensor_dev_attr(attr)->index;
	struct max1668_data *data = max1668_update_device(dev);

	if (IS_ERR(data))
		return PTR_ERR(data);

	return sprintf(buf, "%u\n", (data->alarms >> index) & 0x1);
}

static ssize_t show_fault(struct device *dev,
			  struct device_attribute *devattr, char *buf)
{
	int index = to_sensor_dev_attr(devattr)->index;
	struct max1668_data *data = max1668_update_device(dev);

	if (IS_ERR(data))
		return PTR_ERR(data);

	return sprintf(buf, "%u\n",
		       (data->alarms & (1 << 12)) && data->temp[index] == 127);
}

static ssize_t set_temp_max(struct device *dev,
			    struct device_attribute *devattr,
			    const char *buf, size_t count)
{
	int index = to_sensor_dev_attr(devattr)->index;
	struct max1668_data *data = dev_get_drvdata(dev);
	struct i2c_client *client = data->client;
	long temp;
	int ret;

	ret = kstrtol(buf, 10, &temp);
	if (ret < 0)
		return ret;

	mutex_lock(&data->update_lock);
	data->temp_max[index] = clamp_val(temp/1000, -128, 127);
	ret = i2c_smbus_write_byte_data(client,
					MAX1668_REG_LIMH_WR(index),
					data->temp_max[index]);
	if (ret < 0)
		count = ret;
	mutex_unlock(&data->update_lock);

	return count;
}

static ssize_t set_temp_min(struct device *dev,
			    struct device_attribute *devattr,
			    const char *buf, size_t count)
{
	int index = to_sensor_dev_attr(devattr)->index;
	struct max1668_data *data = dev_get_drvdata(dev);
	struct i2c_client *client = data->client;
	long temp;
	int ret;

	ret = kstrtol(buf, 10, &temp);
	if (ret < 0)
		return ret;

	mutex_lock(&data->update_lock);
	data->temp_min[index] = clamp_val(temp/1000, -128, 127);
	ret = i2c_smbus_write_byte_data(client,
					MAX1668_REG_LIML_WR(index),
					data->temp_min[index]);
	if (ret < 0)
		count = ret;
	mutex_unlock(&data->update_lock);

	return count;
}

static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0);
static SENSOR_DEVICE_ATTR(temp1_max, S_IRUGO, show_temp_max,
				set_temp_max, 0);
static SENSOR_DEVICE_ATTR(temp1_min, S_IRUGO, show_temp_min,
				set_temp_min, 0);
static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_temp, NULL, 1);
static SENSOR_DEVICE_ATTR(temp2_max, S_IRUGO, show_temp_max,
				set_temp_max, 1);
static SENSOR_DEVICE_ATTR(temp2_min, S_IRUGO, show_temp_min,
				set_temp_min, 1);
static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, show_temp, NULL, 2);
static SENSOR_DEVICE_ATTR(temp3_max, S_IRUGO, show_temp_max,
				set_temp_max, 2);
static SENSOR_DEVICE_ATTR(temp3_min, S_IRUGO, show_temp_min,
				set_temp_min, 2);
static SENSOR_DEVICE_ATTR(temp4_input, S_IRUGO, show_temp, NULL, 3);
static SENSOR_DEVICE_ATTR(temp4_max, S_IRUGO, show_temp_max,
				set_temp_max, 3);
static SENSOR_DEVICE_ATTR(temp4_min, S_IRUGO, show_temp_min,
				set_temp_min, 3);
static SENSOR_DEVICE_ATTR(temp5_input, S_IRUGO, show_temp, NULL, 4);
static SENSOR_DEVICE_ATTR(temp5_max, S_IRUGO, show_temp_max,
				set_temp_max, 4);
static SENSOR_DEVICE_ATTR(temp5_min, S_IRUGO, show_temp_min,
				set_temp_min, 4);

static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_alarm, NULL, 14);
static SENSOR_DEVICE_ATTR(temp1_min_alarm, S_IRUGO, show_alarm, NULL, 13);
static SENSOR_DEVICE_ATTR(temp2_min_alarm, S_IRUGO, show_alarm, NULL, 7);
static SENSOR_DEVICE_ATTR(temp2_max_alarm, S_IRUGO, show_alarm, NULL, 6);
static SENSOR_DEVICE_ATTR(temp3_min_alarm, S_IRUGO, show_alarm, NULL, 5);
static SENSOR_DEVICE_ATTR(temp3_max_alarm, S_IRUGO, show_alarm, NULL, 4);
static SENSOR_DEVICE_ATTR(temp4_min_alarm, S_IRUGO, show_alarm, NULL, 3);
static SENSOR_DEVICE_ATTR(temp4_max_alarm, S_IRUGO, show_alarm, NULL, 2);
static SENSOR_DEVICE_ATTR(temp5_min_alarm, S_IRUGO, show_alarm, NULL, 1);
static SENSOR_DEVICE_ATTR(temp5_max_alarm, S_IRUGO, show_alarm, NULL, 0);

static SENSOR_DEVICE_ATTR(temp2_fault, S_IRUGO, show_fault, NULL, 1);
static SENSOR_DEVICE_ATTR(temp3_fault, S_IRUGO, show_fault, NULL, 2);
static SENSOR_DEVICE_ATTR(temp4_fault, S_IRUGO, show_fault, NULL, 3);
static SENSOR_DEVICE_ATTR(temp5_fault, S_IRUGO, show_fault, NULL, 4);

/* Attributes common to MAX1668, MAX1989 and MAX1805 */
static struct attribute *max1668_attribute_common[] = {
	&sensor_dev_attr_temp1_max.dev_attr.attr,
	&sensor_dev_attr_temp1_min.dev_attr.attr,
	&sensor_dev_attr_temp1_input.dev_attr.attr,
	&sensor_dev_attr_temp2_max.dev_attr.attr,
	&sensor_dev_attr_temp2_min.dev_attr.attr,
	&sensor_dev_attr_temp2_input.dev_attr.attr,
	&sensor_dev_attr_temp3_max.dev_attr.attr,
	&sensor_dev_attr_temp3_min.dev_attr.attr,
	&sensor_dev_attr_temp3_input.dev_attr.attr,

	&sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
	&sensor_dev_attr_temp1_min_alarm.dev_attr.attr,
	&sensor_dev_attr_temp2_max_alarm.dev_attr.attr,
	&sensor_dev_attr_temp2_min_alarm.dev_attr.attr,
	&sensor_dev_attr_temp3_max_alarm.dev_attr.attr,
	&sensor_dev_attr_temp3_min_alarm.dev_attr.attr,

	&sensor_dev_attr_temp2_fault.dev_attr.attr,
	&sensor_dev_attr_temp3_fault.dev_attr.attr,
	NULL
};

/* Attributes not present on MAX1805 */
static struct attribute *max1668_attribute_unique[] = {
	&sensor_dev_attr_temp4_max.dev_attr.attr,
	&sensor_dev_attr_temp4_min.dev_attr.attr,
	&sensor_dev_attr_temp4_input.dev_attr.attr,
	&sensor_dev_attr_temp5_max.dev_attr.attr,
	&sensor_dev_attr_temp5_min.dev_attr.attr,
	&sensor_dev_attr_temp5_input.dev_attr.attr,

	&sensor_dev_attr_temp4_max_alarm.dev_attr.attr,
	&sensor_dev_attr_temp4_min_alarm.dev_attr.attr,
	&sensor_dev_attr_temp5_max_alarm.dev_attr.attr,
	&sensor_dev_attr_temp5_min_alarm.dev_attr.attr,

	&sensor_dev_attr_temp4_fault.dev_attr.attr,
	&sensor_dev_attr_temp5_fault.dev_attr.attr,
	NULL
};

static umode_t max1668_attribute_mode(struct kobject *kobj,
				     struct attribute *attr, int index)
{
	umode_t ret = S_IRUGO;
	if (read_only)
		return ret;
	if (attr == &sensor_dev_attr_temp1_max.dev_attr.attr ||
	    attr == &sensor_dev_attr_temp2_max.dev_attr.attr ||
	    attr == &sensor_dev_attr_temp3_max.dev_attr.attr ||
	    attr == &sensor_dev_attr_temp4_max.dev_attr.attr ||
	    attr == &sensor_dev_attr_temp5_max.dev_attr.attr ||
	    attr == &sensor_dev_attr_temp1_min.dev_attr.attr ||
	    attr == &sensor_dev_attr_temp2_min.dev_attr.attr ||
	    attr == &sensor_dev_attr_temp3_min.dev_attr.attr ||
	    attr == &sensor_dev_attr_temp4_min.dev_attr.attr ||
	    attr == &sensor_dev_attr_temp5_min.dev_attr.attr)
		ret |= S_IWUSR;
	return ret;
}

static const struct attribute_group max1668_group_common = {
	.attrs = max1668_attribute_common,
	.is_visible = max1668_attribute_mode
};

static const struct attribute_group max1668_group_unique = {
	.attrs = max1668_attribute_unique,
	.is_visible = max1668_attribute_mode
};

/* Return 0 if detection is successful, -ENODEV otherwise */
static int max1668_detect(struct i2c_client *client,
			  struct i2c_board_info *info)
{
	struct i2c_adapter *adapter = client->adapter;
	const char *type_name;
	int man_id, dev_id;

	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
		return -ENODEV;

	/* Check for unsupported part */
	man_id = i2c_smbus_read_byte_data(client, MAX1668_REG_MAN_ID);
	if (man_id != MAN_ID_MAXIM)
		return -ENODEV;

	dev_id = i2c_smbus_read_byte_data(client, MAX1668_REG_DEV_ID);
	if (dev_id < 0)
		return -ENODEV;

	type_name = NULL;
	if (dev_id == DEV_ID_MAX1668)
		type_name = "max1668";
	else if (dev_id == DEV_ID_MAX1805)
		type_name = "max1805";
	else if (dev_id == DEV_ID_MAX1989)
		type_name = "max1989";

	if (!type_name)
		return -ENODEV;

	strscpy(info->type, type_name, I2C_NAME_SIZE);

	return 0;
}

static const struct i2c_device_id max1668_id[];

static int max1668_probe(struct i2c_client *client)
{
	struct i2c_adapter *adapter = client->adapter;
	struct device *dev = &client->dev;
	struct device *hwmon_dev;
	struct max1668_data *data;

	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
		return -ENODEV;

	data = devm_kzalloc(dev, sizeof(struct max1668_data), GFP_KERNEL);
	if (!data)
		return -ENOMEM;

	data->client = client;
	data->type = i2c_match_id(max1668_id, client)->driver_data;
	mutex_init(&data->update_lock);

	/* sysfs hooks */
	data->groups[0] = &max1668_group_common;
	if (data->type == max1668 || data->type == max1989)
		data->groups[1] = &max1668_group_unique;

	hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
							   data, data->groups);
	return PTR_ERR_OR_ZERO(hwmon_dev);
}

static const struct i2c_device_id max1668_id[] = {
	{ "max1668", max1668 },
	{ "max1805", max1805 },
	{ "max1989", max1989 },
	{ }
};
MODULE_DEVICE_TABLE(i2c, max1668_id);

/* This is the driver that will be inserted */
static struct i2c_driver max1668_driver = {
	.class = I2C_CLASS_HWMON,
	.driver = {
		  .name	= "max1668",
		  },
	.probe_new = max1668_probe,
	.id_table = max1668_id,
	.detect	= max1668_detect,
	.address_list = max1668_addr_list,
};

module_i2c_driver(max1668_driver);

MODULE_AUTHOR("David George <david.george@ska.ac.za>");
MODULE_DESCRIPTION("MAX1668 remote temperature sensor driver");
MODULE_LICENSE("GPL");