blob: 340fc78c8ddedd9e73b697fde9479ec285e8bbcf [file] [log] [blame]
Guenter Roeck4453d732010-08-09 17:21:08 -07001/*
2 * jc42.c - driver for Jedec JC42.4 compliant temperature sensors
3 *
4 * Copyright (c) 2010 Ericsson AB.
5 *
6 * Derived from lm77.c by Andras BALI <drewie@freemail.hu>.
7 *
8 * JC42.4 compliant temperature sensors are typically used on memory modules.
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
14 *
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
19 *
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
23 */
24
25#include <linux/module.h>
26#include <linux/init.h>
27#include <linux/slab.h>
28#include <linux/jiffies.h>
29#include <linux/i2c.h>
30#include <linux/hwmon.h>
31#include <linux/hwmon-sysfs.h>
32#include <linux/err.h>
33#include <linux/mutex.h>
34
35/* Addresses to scan */
36static const unsigned short normal_i2c[] = {
37 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, I2C_CLIENT_END };
38
39/* JC42 registers. All registers are 16 bit. */
40#define JC42_REG_CAP 0x00
41#define JC42_REG_CONFIG 0x01
42#define JC42_REG_TEMP_UPPER 0x02
43#define JC42_REG_TEMP_LOWER 0x03
44#define JC42_REG_TEMP_CRITICAL 0x04
45#define JC42_REG_TEMP 0x05
46#define JC42_REG_MANID 0x06
47#define JC42_REG_DEVICEID 0x07
48
49/* Status bits in temperature register */
50#define JC42_ALARM_CRIT_BIT 15
51#define JC42_ALARM_MAX_BIT 14
52#define JC42_ALARM_MIN_BIT 13
53
54/* Configuration register defines */
55#define JC42_CFG_CRIT_ONLY (1 << 2)
56#define JC42_CFG_SHUTDOWN (1 << 8)
57#define JC42_CFG_HYST_SHIFT 9
58#define JC42_CFG_HYST_MASK 0x03
59
60/* Capabilities */
61#define JC42_CAP_RANGE (1 << 2)
62
63/* Manufacturer IDs */
64#define ADT_MANID 0x11d4 /* Analog Devices */
65#define MAX_MANID 0x004d /* Maxim */
66#define IDT_MANID 0x00b3 /* IDT */
67#define MCP_MANID 0x0054 /* Microchip */
68#define NXP_MANID 0x1131 /* NXP Semiconductors */
69#define ONS_MANID 0x1b09 /* ON Semiconductor */
70#define STM_MANID 0x104a /* ST Microelectronics */
71
72/* Supported chips */
73
74/* Analog Devices */
75#define ADT7408_DEVID 0x0801
76#define ADT7408_DEVID_MASK 0xffff
77
78/* IDT */
79#define TS3000B3_DEVID 0x2903 /* Also matches TSE2002B3 */
80#define TS3000B3_DEVID_MASK 0xffff
81
82/* Maxim */
83#define MAX6604_DEVID 0x3e00
84#define MAX6604_DEVID_MASK 0xffff
85
86/* Microchip */
87#define MCP98242_DEVID 0x2000
88#define MCP98242_DEVID_MASK 0xfffc
89
90#define MCP98243_DEVID 0x2100
91#define MCP98243_DEVID_MASK 0xfffc
92
93#define MCP9843_DEVID 0x0000 /* Also matches mcp9805 */
94#define MCP9843_DEVID_MASK 0xfffe
95
96/* NXP */
97#define SE97_DEVID 0xa200
98#define SE97_DEVID_MASK 0xfffc
99
100#define SE98_DEVID 0xa100
101#define SE98_DEVID_MASK 0xfffc
102
103/* ON Semiconductor */
104#define CAT6095_DEVID 0x0800 /* Also matches CAT34TS02 */
105#define CAT6095_DEVID_MASK 0xffe0
106
107/* ST Microelectronics */
108#define STTS424_DEVID 0x0101
109#define STTS424_DEVID_MASK 0xffff
110
111#define STTS424E_DEVID 0x0000
112#define STTS424E_DEVID_MASK 0xfffe
113
114static u16 jc42_hysteresis[] = { 0, 1500, 3000, 6000 };
115
116struct jc42_chips {
117 u16 manid;
118 u16 devid;
119 u16 devid_mask;
120};
121
122static struct jc42_chips jc42_chips[] = {
123 { ADT_MANID, ADT7408_DEVID, ADT7408_DEVID_MASK },
124 { IDT_MANID, TS3000B3_DEVID, TS3000B3_DEVID_MASK },
125 { MAX_MANID, MAX6604_DEVID, MAX6604_DEVID_MASK },
126 { MCP_MANID, MCP98242_DEVID, MCP98242_DEVID_MASK },
127 { MCP_MANID, MCP98243_DEVID, MCP98243_DEVID_MASK },
128 { MCP_MANID, MCP9843_DEVID, MCP9843_DEVID_MASK },
129 { NXP_MANID, SE97_DEVID, SE97_DEVID_MASK },
130 { ONS_MANID, CAT6095_DEVID, CAT6095_DEVID_MASK },
131 { NXP_MANID, SE98_DEVID, SE98_DEVID_MASK },
132 { STM_MANID, STTS424_DEVID, STTS424_DEVID_MASK },
133 { STM_MANID, STTS424E_DEVID, STTS424E_DEVID_MASK },
134};
135
136/* Each client has this additional data */
137struct jc42_data {
138 struct device *hwmon_dev;
139 struct mutex update_lock; /* protect register access */
140 bool extended; /* true if extended range supported */
141 bool valid;
142 unsigned long last_updated; /* In jiffies */
143 u16 orig_config; /* original configuration */
144 u16 config; /* current configuration */
145 u16 temp_input; /* Temperatures */
146 u16 temp_crit;
147 u16 temp_min;
148 u16 temp_max;
149};
150
151static int jc42_probe(struct i2c_client *client,
152 const struct i2c_device_id *id);
153static int jc42_detect(struct i2c_client *client, struct i2c_board_info *info);
154static int jc42_remove(struct i2c_client *client);
155static int jc42_read_value(struct i2c_client *client, u8 reg);
156static int jc42_write_value(struct i2c_client *client, u8 reg, u16 value);
157
158static struct jc42_data *jc42_update_device(struct device *dev);
159
160static const struct i2c_device_id jc42_id[] = {
161 { "adt7408", 0 },
162 { "cat94ts02", 0 },
163 { "cat6095", 0 },
164 { "jc42", 0 },
165 { "max6604", 0 },
166 { "mcp9805", 0 },
167 { "mcp98242", 0 },
168 { "mcp98243", 0 },
169 { "mcp9843", 0 },
170 { "se97", 0 },
171 { "se97b", 0 },
172 { "se98", 0 },
173 { "stts424", 0 },
174 { "tse2002b3", 0 },
175 { "ts3000b3", 0 },
176 { }
177};
178MODULE_DEVICE_TABLE(i2c, jc42_id);
179
180#ifdef CONFIG_PM
181
182static int jc42_suspend(struct device *dev)
183{
184 struct i2c_client *client = to_i2c_client(dev);
185 struct jc42_data *data = i2c_get_clientdata(client);
186
187 data->config |= JC42_CFG_SHUTDOWN;
188 jc42_write_value(client, JC42_REG_CONFIG, data->config);
189 return 0;
190}
191
192static int jc42_resume(struct device *dev)
193{
194 struct i2c_client *client = to_i2c_client(dev);
195 struct jc42_data *data = i2c_get_clientdata(client);
196
197 data->config &= ~JC42_CFG_SHUTDOWN;
198 jc42_write_value(client, JC42_REG_CONFIG, data->config);
199 return 0;
200}
201
202static const struct dev_pm_ops jc42_dev_pm_ops = {
203 .suspend = jc42_suspend,
204 .resume = jc42_resume,
205};
206
207#define JC42_DEV_PM_OPS (&jc42_dev_pm_ops)
208#else
209#define JC42_DEV_PM_OPS NULL
210#endif /* CONFIG_PM */
211
212/* This is the driver that will be inserted */
213static struct i2c_driver jc42_driver = {
214 .class = I2C_CLASS_HWMON,
215 .driver = {
216 .name = "jc42",
217 .pm = JC42_DEV_PM_OPS,
218 },
219 .probe = jc42_probe,
220 .remove = jc42_remove,
221 .id_table = jc42_id,
222 .detect = jc42_detect,
223 .address_list = normal_i2c,
224};
225
226#define JC42_TEMP_MIN_EXTENDED (-40000)
227#define JC42_TEMP_MIN 0
228#define JC42_TEMP_MAX 125000
229
230static u16 jc42_temp_to_reg(int temp, bool extended)
231{
232 int ntemp = SENSORS_LIMIT(temp,
233 extended ? JC42_TEMP_MIN_EXTENDED :
234 JC42_TEMP_MIN, JC42_TEMP_MAX);
235
236 /* convert from 0.001 to 0.0625 resolution */
237 return (ntemp * 2 / 125) & 0x1fff;
238}
239
240static int jc42_temp_from_reg(s16 reg)
241{
242 reg &= 0x1fff;
243
244 /* sign extend register */
245 if (reg & 0x1000)
246 reg |= 0xf000;
247
248 /* convert from 0.0625 to 0.001 resolution */
249 return reg * 125 / 2;
250}
251
252/* sysfs stuff */
253
254/* read routines for temperature limits */
255#define show(value) \
256static ssize_t show_##value(struct device *dev, \
257 struct device_attribute *attr, \
258 char *buf) \
259{ \
260 struct jc42_data *data = jc42_update_device(dev); \
261 if (IS_ERR(data)) \
262 return PTR_ERR(data); \
263 return sprintf(buf, "%d\n", jc42_temp_from_reg(data->value)); \
264}
265
266show(temp_input);
267show(temp_crit);
268show(temp_min);
269show(temp_max);
270
271/* read routines for hysteresis values */
272static ssize_t show_temp_crit_hyst(struct device *dev,
273 struct device_attribute *attr, char *buf)
274{
275 struct jc42_data *data = jc42_update_device(dev);
276 int temp, hyst;
277
278 if (IS_ERR(data))
279 return PTR_ERR(data);
280
281 temp = jc42_temp_from_reg(data->temp_crit);
282 hyst = jc42_hysteresis[(data->config >> JC42_CFG_HYST_SHIFT)
283 & JC42_CFG_HYST_MASK];
284 return sprintf(buf, "%d\n", temp - hyst);
285}
286
287static ssize_t show_temp_max_hyst(struct device *dev,
288 struct device_attribute *attr, char *buf)
289{
290 struct jc42_data *data = jc42_update_device(dev);
291 int temp, hyst;
292
293 if (IS_ERR(data))
294 return PTR_ERR(data);
295
296 temp = jc42_temp_from_reg(data->temp_max);
297 hyst = jc42_hysteresis[(data->config >> JC42_CFG_HYST_SHIFT)
298 & JC42_CFG_HYST_MASK];
299 return sprintf(buf, "%d\n", temp - hyst);
300}
301
302/* write routines */
303#define set(value, reg) \
304static ssize_t set_##value(struct device *dev, \
305 struct device_attribute *attr, \
306 const char *buf, size_t count) \
307{ \
308 struct i2c_client *client = to_i2c_client(dev); \
309 struct jc42_data *data = i2c_get_clientdata(client); \
310 int err, ret = count; \
311 long val; \
312 if (strict_strtol(buf, 10, &val) < 0) \
313 return -EINVAL; \
314 mutex_lock(&data->update_lock); \
315 data->value = jc42_temp_to_reg(val, data->extended); \
316 err = jc42_write_value(client, reg, data->value); \
317 if (err < 0) \
318 ret = err; \
319 mutex_unlock(&data->update_lock); \
320 return ret; \
321}
322
323set(temp_min, JC42_REG_TEMP_LOWER);
324set(temp_max, JC42_REG_TEMP_UPPER);
325set(temp_crit, JC42_REG_TEMP_CRITICAL);
326
327/* JC42.4 compliant chips only support four hysteresis values.
328 * Pick best choice and go from there. */
329static ssize_t set_temp_crit_hyst(struct device *dev,
330 struct device_attribute *attr,
331 const char *buf, size_t count)
332{
333 struct i2c_client *client = to_i2c_client(dev);
334 struct jc42_data *data = i2c_get_clientdata(client);
335 long val;
336 int diff, hyst;
337 int err;
338 int ret = count;
339
340 if (strict_strtoul(buf, 10, &val) < 0)
341 return -EINVAL;
342
343 diff = jc42_temp_from_reg(data->temp_crit) - val;
344 hyst = 0;
345 if (diff > 0) {
346 if (diff < 2250)
347 hyst = 1; /* 1.5 degrees C */
348 else if (diff < 4500)
349 hyst = 2; /* 3.0 degrees C */
350 else
351 hyst = 3; /* 6.0 degrees C */
352 }
353
354 mutex_lock(&data->update_lock);
355 data->config = (data->config
356 & ~(JC42_CFG_HYST_MASK << JC42_CFG_HYST_SHIFT))
357 | (hyst << JC42_CFG_HYST_SHIFT);
358 err = jc42_write_value(client, JC42_REG_CONFIG, data->config);
359 if (err < 0)
360 ret = err;
361 mutex_unlock(&data->update_lock);
362 return ret;
363}
364
365static ssize_t show_alarm(struct device *dev,
366 struct device_attribute *attr, char *buf)
367{
368 u16 bit = to_sensor_dev_attr(attr)->index;
369 struct jc42_data *data = jc42_update_device(dev);
370 u16 val;
371
372 if (IS_ERR(data))
373 return PTR_ERR(data);
374
375 val = data->temp_input;
376 if (bit != JC42_ALARM_CRIT_BIT && (data->config & JC42_CFG_CRIT_ONLY))
377 val = 0;
378 return sprintf(buf, "%u\n", (val >> bit) & 1);
379}
380
381static DEVICE_ATTR(temp1_input, S_IRUGO,
382 show_temp_input, NULL);
383static DEVICE_ATTR(temp1_crit, S_IWUSR | S_IRUGO,
384 show_temp_crit, set_temp_crit);
385static DEVICE_ATTR(temp1_min, S_IWUSR | S_IRUGO,
386 show_temp_min, set_temp_min);
387static DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO,
388 show_temp_max, set_temp_max);
389
390static DEVICE_ATTR(temp1_crit_hyst, S_IWUSR | S_IRUGO,
391 show_temp_crit_hyst, set_temp_crit_hyst);
392static DEVICE_ATTR(temp1_max_hyst, S_IRUGO,
393 show_temp_max_hyst, NULL);
394
395static SENSOR_DEVICE_ATTR(temp1_crit_alarm, S_IRUGO, show_alarm, NULL,
396 JC42_ALARM_CRIT_BIT);
397static SENSOR_DEVICE_ATTR(temp1_min_alarm, S_IRUGO, show_alarm, NULL,
398 JC42_ALARM_MIN_BIT);
399static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_alarm, NULL,
400 JC42_ALARM_MAX_BIT);
401
402static struct attribute *jc42_attributes[] = {
403 &dev_attr_temp1_input.attr,
404 &dev_attr_temp1_crit.attr,
405 &dev_attr_temp1_min.attr,
406 &dev_attr_temp1_max.attr,
407 &dev_attr_temp1_crit_hyst.attr,
408 &dev_attr_temp1_max_hyst.attr,
409 &sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
410 &sensor_dev_attr_temp1_min_alarm.dev_attr.attr,
411 &sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
412 NULL
413};
414
415static const struct attribute_group jc42_group = {
416 .attrs = jc42_attributes,
417};
418
419/* Return 0 if detection is successful, -ENODEV otherwise */
420static int jc42_detect(struct i2c_client *new_client,
421 struct i2c_board_info *info)
422{
423 struct i2c_adapter *adapter = new_client->adapter;
424 int i, config, cap, manid, devid;
425
426 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA |
427 I2C_FUNC_SMBUS_WORD_DATA))
428 return -ENODEV;
429
430 cap = jc42_read_value(new_client, JC42_REG_CAP);
431 config = jc42_read_value(new_client, JC42_REG_CONFIG);
432 manid = jc42_read_value(new_client, JC42_REG_MANID);
433 devid = jc42_read_value(new_client, JC42_REG_DEVICEID);
434
435 if (cap < 0 || config < 0 || manid < 0 || devid < 0)
436 return -ENODEV;
437
438 if ((cap & 0xff00) || (config & 0xf800))
439 return -ENODEV;
440
441 for (i = 0; i < ARRAY_SIZE(jc42_chips); i++) {
442 struct jc42_chips *chip = &jc42_chips[i];
443 if (manid == chip->manid &&
444 (devid & chip->devid_mask) == chip->devid) {
445 strlcpy(info->type, "jc42", I2C_NAME_SIZE);
446 return 0;
447 }
448 }
449 return -ENODEV;
450}
451
452static int jc42_probe(struct i2c_client *new_client,
453 const struct i2c_device_id *id)
454{
455 struct jc42_data *data;
456 int config, cap, err;
457
458 data = kzalloc(sizeof(struct jc42_data), GFP_KERNEL);
459 if (!data) {
460 err = -ENOMEM;
461 goto exit;
462 }
463
464 i2c_set_clientdata(new_client, data);
465 mutex_init(&data->update_lock);
466
467 cap = jc42_read_value(new_client, JC42_REG_CAP);
468 if (cap < 0) {
469 err = -EINVAL;
470 goto exit_free;
471 }
472 data->extended = !!(cap & JC42_CAP_RANGE);
473
474 config = jc42_read_value(new_client, JC42_REG_CONFIG);
475 if (config < 0) {
476 err = -EINVAL;
477 goto exit_free;
478 }
479 data->orig_config = config;
480 if (config & JC42_CFG_SHUTDOWN) {
481 config &= ~JC42_CFG_SHUTDOWN;
482 jc42_write_value(new_client, JC42_REG_CONFIG, config);
483 }
484 data->config = config;
485
486 /* Register sysfs hooks */
487 err = sysfs_create_group(&new_client->dev.kobj, &jc42_group);
488 if (err)
489 goto exit_free;
490
491 data->hwmon_dev = hwmon_device_register(&new_client->dev);
492 if (IS_ERR(data->hwmon_dev)) {
493 err = PTR_ERR(data->hwmon_dev);
494 goto exit_remove;
495 }
496
497 return 0;
498
499exit_remove:
500 sysfs_remove_group(&new_client->dev.kobj, &jc42_group);
501exit_free:
502 kfree(data);
503exit:
504 return err;
505}
506
507static int jc42_remove(struct i2c_client *client)
508{
509 struct jc42_data *data = i2c_get_clientdata(client);
510 hwmon_device_unregister(data->hwmon_dev);
511 sysfs_remove_group(&client->dev.kobj, &jc42_group);
512 if (data->config != data->orig_config)
513 jc42_write_value(client, JC42_REG_CONFIG, data->orig_config);
514 kfree(data);
515 return 0;
516}
517
518/* All registers are word-sized. */
519static int jc42_read_value(struct i2c_client *client, u8 reg)
520{
521 int ret = i2c_smbus_read_word_data(client, reg);
522 if (ret < 0)
523 return ret;
524 return swab16(ret);
525}
526
527static int jc42_write_value(struct i2c_client *client, u8 reg, u16 value)
528{
529 return i2c_smbus_write_word_data(client, reg, swab16(value));
530}
531
532static struct jc42_data *jc42_update_device(struct device *dev)
533{
534 struct i2c_client *client = to_i2c_client(dev);
535 struct jc42_data *data = i2c_get_clientdata(client);
536 struct jc42_data *ret = data;
537 int val;
538
539 mutex_lock(&data->update_lock);
540
541 if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
542 val = jc42_read_value(client, JC42_REG_TEMP);
543 if (val < 0) {
544 ret = ERR_PTR(val);
545 goto abort;
546 }
547 data->temp_input = val;
548
549 val = jc42_read_value(client, JC42_REG_TEMP_CRITICAL);
550 if (val < 0) {
551 ret = ERR_PTR(val);
552 goto abort;
553 }
554 data->temp_crit = val;
555
556 val = jc42_read_value(client, JC42_REG_TEMP_LOWER);
557 if (val < 0) {
558 ret = ERR_PTR(val);
559 goto abort;
560 }
561 data->temp_min = val;
562
563 val = jc42_read_value(client, JC42_REG_TEMP_UPPER);
564 if (val < 0) {
565 ret = ERR_PTR(val);
566 goto abort;
567 }
568 data->temp_max = val;
569
570 data->last_updated = jiffies;
571 data->valid = true;
572 }
573abort:
574 mutex_unlock(&data->update_lock);
575 return ret;
576}
577
578static int __init sensors_jc42_init(void)
579{
580 return i2c_add_driver(&jc42_driver);
581}
582
583static void __exit sensors_jc42_exit(void)
584{
585 i2c_del_driver(&jc42_driver);
586}
587
588MODULE_AUTHOR("Guenter Roeck <guenter.roeck@ericsson.com>");
589MODULE_DESCRIPTION("JC42 driver");
590MODULE_LICENSE("GPL");
591
592module_init(sensors_jc42_init);
593module_exit(sensors_jc42_exit);