2 * jc42.c - driver for Jedec JC42.4 compliant temperature sensors
4 * Copyright (c) 2010 Ericsson AB.
6 * Derived from lm77.c by Andras BALI <drewie@freemail.hu>.
8 * JC42.4 compliant temperature sensors are typically used on memory modules.
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.
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.
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.
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>
35 /* Addresses to scan */
36 static const unsigned short normal_i2c[] = {
37 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, I2C_CLIENT_END };
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
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
54 /* Configuration register defines */
55 #define JC42_CFG_CRIT_ONLY (1 << 2)
56 #define JC42_CFG_TCRIT_LOCK (1 << 6)
57 #define JC42_CFG_EVENT_LOCK (1 << 7)
58 #define JC42_CFG_SHUTDOWN (1 << 8)
59 #define JC42_CFG_HYST_SHIFT 9
60 #define JC42_CFG_HYST_MASK 0x03
63 #define JC42_CAP_RANGE (1 << 2)
65 /* Manufacturer IDs */
66 #define ADT_MANID 0x11d4 /* Analog Devices */
67 #define MAX_MANID 0x004d /* Maxim */
68 #define IDT_MANID 0x00b3 /* IDT */
69 #define MCP_MANID 0x0054 /* Microchip */
70 #define NXP_MANID 0x1131 /* NXP Semiconductors */
71 #define ONS_MANID 0x1b09 /* ON Semiconductor */
72 #define STM_MANID 0x104a /* ST Microelectronics */
77 #define ADT7408_DEVID 0x0801
78 #define ADT7408_DEVID_MASK 0xffff
81 #define TS3000B3_DEVID 0x2903 /* Also matches TSE2002B3 */
82 #define TS3000B3_DEVID_MASK 0xffff
85 #define MAX6604_DEVID 0x3e00
86 #define MAX6604_DEVID_MASK 0xffff
89 #define MCP98242_DEVID 0x2000
90 #define MCP98242_DEVID_MASK 0xfffc
92 #define MCP98243_DEVID 0x2100
93 #define MCP98243_DEVID_MASK 0xfffc
95 #define MCP9843_DEVID 0x0000 /* Also matches mcp9805 */
96 #define MCP9843_DEVID_MASK 0xfffe
99 #define SE97_DEVID 0xa200
100 #define SE97_DEVID_MASK 0xfffc
102 #define SE98_DEVID 0xa100
103 #define SE98_DEVID_MASK 0xfffc
105 /* ON Semiconductor */
106 #define CAT6095_DEVID 0x0800 /* Also matches CAT34TS02 */
107 #define CAT6095_DEVID_MASK 0xffe0
109 /* ST Microelectronics */
110 #define STTS424_DEVID 0x0101
111 #define STTS424_DEVID_MASK 0xffff
113 #define STTS424E_DEVID 0x0000
114 #define STTS424E_DEVID_MASK 0xfffe
116 static u16 jc42_hysteresis[] = { 0, 1500, 3000, 6000 };
124 static struct jc42_chips jc42_chips[] = {
125 { ADT_MANID, ADT7408_DEVID, ADT7408_DEVID_MASK },
126 { IDT_MANID, TS3000B3_DEVID, TS3000B3_DEVID_MASK },
127 { MAX_MANID, MAX6604_DEVID, MAX6604_DEVID_MASK },
128 { MCP_MANID, MCP98242_DEVID, MCP98242_DEVID_MASK },
129 { MCP_MANID, MCP98243_DEVID, MCP98243_DEVID_MASK },
130 { MCP_MANID, MCP9843_DEVID, MCP9843_DEVID_MASK },
131 { NXP_MANID, SE97_DEVID, SE97_DEVID_MASK },
132 { ONS_MANID, CAT6095_DEVID, CAT6095_DEVID_MASK },
133 { NXP_MANID, SE98_DEVID, SE98_DEVID_MASK },
134 { STM_MANID, STTS424_DEVID, STTS424_DEVID_MASK },
135 { STM_MANID, STTS424E_DEVID, STTS424E_DEVID_MASK },
138 /* Each client has this additional data */
140 struct device *hwmon_dev;
141 struct mutex update_lock; /* protect register access */
142 bool extended; /* true if extended range supported */
144 unsigned long last_updated; /* In jiffies */
145 u16 orig_config; /* original configuration */
146 u16 config; /* current configuration */
147 u16 temp_input; /* Temperatures */
153 static int jc42_probe(struct i2c_client *client,
154 const struct i2c_device_id *id);
155 static int jc42_detect(struct i2c_client *client, struct i2c_board_info *info);
156 static int jc42_remove(struct i2c_client *client);
157 static int jc42_read_value(struct i2c_client *client, u8 reg);
158 static int jc42_write_value(struct i2c_client *client, u8 reg, u16 value);
160 static struct jc42_data *jc42_update_device(struct device *dev);
162 static const struct i2c_device_id jc42_id[] = {
180 MODULE_DEVICE_TABLE(i2c, jc42_id);
184 static int jc42_suspend(struct device *dev)
186 struct i2c_client *client = to_i2c_client(dev);
187 struct jc42_data *data = i2c_get_clientdata(client);
189 data->config |= JC42_CFG_SHUTDOWN;
190 jc42_write_value(client, JC42_REG_CONFIG, data->config);
194 static int jc42_resume(struct device *dev)
196 struct i2c_client *client = to_i2c_client(dev);
197 struct jc42_data *data = i2c_get_clientdata(client);
199 data->config &= ~JC42_CFG_SHUTDOWN;
200 jc42_write_value(client, JC42_REG_CONFIG, data->config);
204 static const struct dev_pm_ops jc42_dev_pm_ops = {
205 .suspend = jc42_suspend,
206 .resume = jc42_resume,
209 #define JC42_DEV_PM_OPS (&jc42_dev_pm_ops)
211 #define JC42_DEV_PM_OPS NULL
212 #endif /* CONFIG_PM */
214 /* This is the driver that will be inserted */
215 static struct i2c_driver jc42_driver = {
216 .class = I2C_CLASS_SPD,
219 .pm = JC42_DEV_PM_OPS,
222 .remove = jc42_remove,
224 .detect = jc42_detect,
225 .address_list = normal_i2c,
228 #define JC42_TEMP_MIN_EXTENDED (-40000)
229 #define JC42_TEMP_MIN 0
230 #define JC42_TEMP_MAX 125000
232 static u16 jc42_temp_to_reg(int temp, bool extended)
234 int ntemp = SENSORS_LIMIT(temp,
235 extended ? JC42_TEMP_MIN_EXTENDED :
236 JC42_TEMP_MIN, JC42_TEMP_MAX);
238 /* convert from 0.001 to 0.0625 resolution */
239 return (ntemp * 2 / 125) & 0x1fff;
242 static int jc42_temp_from_reg(s16 reg)
246 /* sign extend register */
250 /* convert from 0.0625 to 0.001 resolution */
251 return reg * 125 / 2;
256 /* read routines for temperature limits */
257 #define show(value) \
258 static ssize_t show_##value(struct device *dev, \
259 struct device_attribute *attr, \
262 struct jc42_data *data = jc42_update_device(dev); \
264 return PTR_ERR(data); \
265 return sprintf(buf, "%d\n", jc42_temp_from_reg(data->value)); \
273 /* read routines for hysteresis values */
274 static ssize_t show_temp_crit_hyst(struct device *dev,
275 struct device_attribute *attr, char *buf)
277 struct jc42_data *data = jc42_update_device(dev);
281 return PTR_ERR(data);
283 temp = jc42_temp_from_reg(data->temp_crit);
284 hyst = jc42_hysteresis[(data->config >> JC42_CFG_HYST_SHIFT)
285 & JC42_CFG_HYST_MASK];
286 return sprintf(buf, "%d\n", temp - hyst);
289 static ssize_t show_temp_max_hyst(struct device *dev,
290 struct device_attribute *attr, char *buf)
292 struct jc42_data *data = jc42_update_device(dev);
296 return PTR_ERR(data);
298 temp = jc42_temp_from_reg(data->temp_max);
299 hyst = jc42_hysteresis[(data->config >> JC42_CFG_HYST_SHIFT)
300 & JC42_CFG_HYST_MASK];
301 return sprintf(buf, "%d\n", temp - hyst);
305 #define set(value, reg) \
306 static ssize_t set_##value(struct device *dev, \
307 struct device_attribute *attr, \
308 const char *buf, size_t count) \
310 struct i2c_client *client = to_i2c_client(dev); \
311 struct jc42_data *data = i2c_get_clientdata(client); \
312 int err, ret = count; \
314 if (strict_strtol(buf, 10, &val) < 0) \
316 mutex_lock(&data->update_lock); \
317 data->value = jc42_temp_to_reg(val, data->extended); \
318 err = jc42_write_value(client, reg, data->value); \
321 mutex_unlock(&data->update_lock); \
325 set(temp_min, JC42_REG_TEMP_LOWER);
326 set(temp_max, JC42_REG_TEMP_UPPER);
327 set(temp_crit, JC42_REG_TEMP_CRITICAL);
329 /* JC42.4 compliant chips only support four hysteresis values.
330 * Pick best choice and go from there. */
331 static ssize_t set_temp_crit_hyst(struct device *dev,
332 struct device_attribute *attr,
333 const char *buf, size_t count)
335 struct i2c_client *client = to_i2c_client(dev);
336 struct jc42_data *data = i2c_get_clientdata(client);
342 if (strict_strtoul(buf, 10, &val) < 0)
345 diff = jc42_temp_from_reg(data->temp_crit) - val;
349 hyst = 1; /* 1.5 degrees C */
350 else if (diff < 4500)
351 hyst = 2; /* 3.0 degrees C */
353 hyst = 3; /* 6.0 degrees C */
356 mutex_lock(&data->update_lock);
357 data->config = (data->config
358 & ~(JC42_CFG_HYST_MASK << JC42_CFG_HYST_SHIFT))
359 | (hyst << JC42_CFG_HYST_SHIFT);
360 err = jc42_write_value(client, JC42_REG_CONFIG, data->config);
363 mutex_unlock(&data->update_lock);
367 static ssize_t show_alarm(struct device *dev,
368 struct device_attribute *attr, char *buf)
370 u16 bit = to_sensor_dev_attr(attr)->index;
371 struct jc42_data *data = jc42_update_device(dev);
375 return PTR_ERR(data);
377 val = data->temp_input;
378 if (bit != JC42_ALARM_CRIT_BIT && (data->config & JC42_CFG_CRIT_ONLY))
380 return sprintf(buf, "%u\n", (val >> bit) & 1);
383 static DEVICE_ATTR(temp1_input, S_IRUGO,
384 show_temp_input, NULL);
385 static DEVICE_ATTR(temp1_crit, S_IRUGO,
386 show_temp_crit, set_temp_crit);
387 static DEVICE_ATTR(temp1_min, S_IRUGO,
388 show_temp_min, set_temp_min);
389 static DEVICE_ATTR(temp1_max, S_IRUGO,
390 show_temp_max, set_temp_max);
392 static DEVICE_ATTR(temp1_crit_hyst, S_IRUGO,
393 show_temp_crit_hyst, set_temp_crit_hyst);
394 static DEVICE_ATTR(temp1_max_hyst, S_IRUGO,
395 show_temp_max_hyst, NULL);
397 static SENSOR_DEVICE_ATTR(temp1_crit_alarm, S_IRUGO, show_alarm, NULL,
398 JC42_ALARM_CRIT_BIT);
399 static SENSOR_DEVICE_ATTR(temp1_min_alarm, S_IRUGO, show_alarm, NULL,
401 static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_alarm, NULL,
404 static struct attribute *jc42_attributes[] = {
405 &dev_attr_temp1_input.attr,
406 &dev_attr_temp1_crit.attr,
407 &dev_attr_temp1_min.attr,
408 &dev_attr_temp1_max.attr,
409 &dev_attr_temp1_crit_hyst.attr,
410 &dev_attr_temp1_max_hyst.attr,
411 &sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
412 &sensor_dev_attr_temp1_min_alarm.dev_attr.attr,
413 &sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
417 static mode_t jc42_attribute_mode(struct kobject *kobj,
418 struct attribute *attr, int index)
420 struct device *dev = container_of(kobj, struct device, kobj);
421 struct i2c_client *client = to_i2c_client(dev);
422 struct jc42_data *data = i2c_get_clientdata(client);
423 unsigned int config = data->config;
426 if (attr == &dev_attr_temp1_crit.attr)
427 readonly = config & JC42_CFG_TCRIT_LOCK;
428 else if (attr == &dev_attr_temp1_min.attr ||
429 attr == &dev_attr_temp1_max.attr)
430 readonly = config & JC42_CFG_EVENT_LOCK;
431 else if (attr == &dev_attr_temp1_crit_hyst.attr)
432 readonly = config & (JC42_CFG_EVENT_LOCK | JC42_CFG_TCRIT_LOCK);
436 return S_IRUGO | (readonly ? 0 : S_IWUSR);
439 static const struct attribute_group jc42_group = {
440 .attrs = jc42_attributes,
441 .is_visible = jc42_attribute_mode,
444 /* Return 0 if detection is successful, -ENODEV otherwise */
445 static int jc42_detect(struct i2c_client *new_client,
446 struct i2c_board_info *info)
448 struct i2c_adapter *adapter = new_client->adapter;
449 int i, config, cap, manid, devid;
451 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA |
452 I2C_FUNC_SMBUS_WORD_DATA))
455 cap = jc42_read_value(new_client, JC42_REG_CAP);
456 config = jc42_read_value(new_client, JC42_REG_CONFIG);
457 manid = jc42_read_value(new_client, JC42_REG_MANID);
458 devid = jc42_read_value(new_client, JC42_REG_DEVICEID);
460 if (cap < 0 || config < 0 || manid < 0 || devid < 0)
463 if ((cap & 0xff00) || (config & 0xf800))
466 for (i = 0; i < ARRAY_SIZE(jc42_chips); i++) {
467 struct jc42_chips *chip = &jc42_chips[i];
468 if (manid == chip->manid &&
469 (devid & chip->devid_mask) == chip->devid) {
470 strlcpy(info->type, "jc42", I2C_NAME_SIZE);
477 static int jc42_probe(struct i2c_client *new_client,
478 const struct i2c_device_id *id)
480 struct jc42_data *data;
481 int config, cap, err;
483 data = kzalloc(sizeof(struct jc42_data), GFP_KERNEL);
489 i2c_set_clientdata(new_client, data);
490 mutex_init(&data->update_lock);
492 cap = jc42_read_value(new_client, JC42_REG_CAP);
497 data->extended = !!(cap & JC42_CAP_RANGE);
499 config = jc42_read_value(new_client, JC42_REG_CONFIG);
504 data->orig_config = config;
505 if (config & JC42_CFG_SHUTDOWN) {
506 config &= ~JC42_CFG_SHUTDOWN;
507 jc42_write_value(new_client, JC42_REG_CONFIG, config);
509 data->config = config;
511 /* Register sysfs hooks */
512 err = sysfs_create_group(&new_client->dev.kobj, &jc42_group);
516 data->hwmon_dev = hwmon_device_register(&new_client->dev);
517 if (IS_ERR(data->hwmon_dev)) {
518 err = PTR_ERR(data->hwmon_dev);
525 sysfs_remove_group(&new_client->dev.kobj, &jc42_group);
532 static int jc42_remove(struct i2c_client *client)
534 struct jc42_data *data = i2c_get_clientdata(client);
535 hwmon_device_unregister(data->hwmon_dev);
536 sysfs_remove_group(&client->dev.kobj, &jc42_group);
537 if (data->config != data->orig_config)
538 jc42_write_value(client, JC42_REG_CONFIG, data->orig_config);
543 /* All registers are word-sized. */
544 static int jc42_read_value(struct i2c_client *client, u8 reg)
546 int ret = i2c_smbus_read_word_data(client, reg);
552 static int jc42_write_value(struct i2c_client *client, u8 reg, u16 value)
554 return i2c_smbus_write_word_data(client, reg, swab16(value));
557 static struct jc42_data *jc42_update_device(struct device *dev)
559 struct i2c_client *client = to_i2c_client(dev);
560 struct jc42_data *data = i2c_get_clientdata(client);
561 struct jc42_data *ret = data;
564 mutex_lock(&data->update_lock);
566 if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
567 val = jc42_read_value(client, JC42_REG_TEMP);
572 data->temp_input = val;
574 val = jc42_read_value(client, JC42_REG_TEMP_CRITICAL);
579 data->temp_crit = val;
581 val = jc42_read_value(client, JC42_REG_TEMP_LOWER);
586 data->temp_min = val;
588 val = jc42_read_value(client, JC42_REG_TEMP_UPPER);
593 data->temp_max = val;
595 data->last_updated = jiffies;
599 mutex_unlock(&data->update_lock);
603 static int __init sensors_jc42_init(void)
605 return i2c_add_driver(&jc42_driver);
608 static void __exit sensors_jc42_exit(void)
610 i2c_del_driver(&jc42_driver);
613 MODULE_AUTHOR("Guenter Roeck <guenter.roeck@ericsson.com>");
614 MODULE_DESCRIPTION("JC42 driver");
615 MODULE_LICENSE("GPL");
617 module_init(sensors_jc42_init);
618 module_exit(sensors_jc42_exit);