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v3.1
 
  1/*
  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_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
 61
 62/* Capabilities */
 63#define JC42_CAP_RANGE		(1 << 2)
 64
 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 */
 
 
 
 
 
 73
 74/* Supported chips */
 75
 76/* Analog Devices */
 77#define ADT7408_DEVID		0x0801
 78#define ADT7408_DEVID_MASK	0xffff
 79
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 80/* IDT */
 81#define TS3000B3_DEVID		0x2903  /* Also matches TSE2002B3 */
 82#define TS3000B3_DEVID_MASK	0xffff
 
 
 
 
 
 
 83
 84/* Maxim */
 85#define MAX6604_DEVID		0x3e00
 86#define MAX6604_DEVID_MASK	0xffff
 87
 88/* Microchip */
 
 
 
 
 
 
 89#define MCP98242_DEVID		0x2000
 90#define MCP98242_DEVID_MASK	0xfffc
 91
 92#define MCP98243_DEVID		0x2100
 93#define MCP98243_DEVID_MASK	0xfffc
 94
 
 
 
 95#define MCP9843_DEVID		0x0000	/* Also matches mcp9805 */
 96#define MCP9843_DEVID_MASK	0xfffe
 97
 98/* NXP */
 99#define SE97_DEVID		0xa200
100#define SE97_DEVID_MASK		0xfffc
101
102#define SE98_DEVID		0xa100
103#define SE98_DEVID_MASK		0xfffc
104
105/* ON Semiconductor */
106#define CAT6095_DEVID		0x0800	/* Also matches CAT34TS02 */
107#define CAT6095_DEVID_MASK	0xffe0
108
 
 
 
 
 
 
109/* ST Microelectronics */
110#define STTS424_DEVID		0x0101
111#define STTS424_DEVID_MASK	0xffff
112
113#define STTS424E_DEVID		0x0000
114#define STTS424E_DEVID_MASK	0xfffe
115
 
 
 
 
 
 
 
 
 
116static u16 jc42_hysteresis[] = { 0, 1500, 3000, 6000 };
117
118struct jc42_chips {
119	u16 manid;
120	u16 devid;
121	u16 devid_mask;
122};
123
124static 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 },
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
136};
137
138/* Each client has this additional data */
139struct jc42_data {
140	struct device	*hwmon_dev;
141	struct mutex	update_lock;	/* protect register access */
142	bool		extended;	/* true if extended range supported */
143	bool		valid;
144	unsigned long	last_updated;	/* In jiffies */
145	u16		orig_config;	/* original configuration */
146	u16		config;		/* current configuration */
147	u16		temp_input;	/* Temperatures */
148	u16		temp_crit;
149	u16		temp_min;
150	u16		temp_max;
151};
152
153static int jc42_probe(struct i2c_client *client,
154		      const struct i2c_device_id *id);
155static int jc42_detect(struct i2c_client *client, struct i2c_board_info *info);
156static int jc42_remove(struct i2c_client *client);
157static int jc42_read_value(struct i2c_client *client, u8 reg);
158static int jc42_write_value(struct i2c_client *client, u8 reg, u16 value);
159
160static struct jc42_data *jc42_update_device(struct device *dev);
161
162static const struct i2c_device_id jc42_id[] = {
163	{ "adt7408", 0 },
164	{ "cat94ts02", 0 },
165	{ "cat6095", 0 },
166	{ "jc42", 0 },
167	{ "max6604", 0 },
168	{ "mcp9805", 0 },
169	{ "mcp98242", 0 },
170	{ "mcp98243", 0 },
171	{ "mcp9843", 0 },
172	{ "se97", 0 },
173	{ "se97b", 0 },
174	{ "se98", 0 },
175	{ "stts424", 0 },
176	{ "tse2002b3", 0 },
177	{ "ts3000b3", 0 },
178	{ }
179};
180MODULE_DEVICE_TABLE(i2c, jc42_id);
181
182#ifdef CONFIG_PM
183
184static int jc42_suspend(struct device *dev)
185{
186	struct i2c_client *client = to_i2c_client(dev);
187	struct jc42_data *data = i2c_get_clientdata(client);
188
189	data->config |= JC42_CFG_SHUTDOWN;
190	jc42_write_value(client, JC42_REG_CONFIG, data->config);
191	return 0;
192}
193
194static int jc42_resume(struct device *dev)
195{
196	struct i2c_client *client = to_i2c_client(dev);
197	struct jc42_data *data = i2c_get_clientdata(client);
198
199	data->config &= ~JC42_CFG_SHUTDOWN;
200	jc42_write_value(client, JC42_REG_CONFIG, data->config);
201	return 0;
202}
203
204static const struct dev_pm_ops jc42_dev_pm_ops = {
205	.suspend = jc42_suspend,
206	.resume = jc42_resume,
207};
208
209#define JC42_DEV_PM_OPS (&jc42_dev_pm_ops)
210#else
211#define JC42_DEV_PM_OPS NULL
212#endif /* CONFIG_PM */
213
214/* This is the driver that will be inserted */
215static struct i2c_driver jc42_driver = {
216	.class		= I2C_CLASS_SPD,
217	.driver = {
218		.name	= "jc42",
219		.pm = JC42_DEV_PM_OPS,
220	},
221	.probe		= jc42_probe,
222	.remove		= jc42_remove,
223	.id_table	= jc42_id,
224	.detect		= jc42_detect,
225	.address_list	= normal_i2c,
226};
227
228#define JC42_TEMP_MIN_EXTENDED	(-40000)
229#define JC42_TEMP_MIN		0
230#define JC42_TEMP_MAX		125000
231
232static u16 jc42_temp_to_reg(int temp, bool extended)
233{
234	int ntemp = SENSORS_LIMIT(temp,
235				  extended ? JC42_TEMP_MIN_EXTENDED :
236				  JC42_TEMP_MIN, JC42_TEMP_MAX);
237
238	/* convert from 0.001 to 0.0625 resolution */
239	return (ntemp * 2 / 125) & 0x1fff;
240}
241
242static int jc42_temp_from_reg(s16 reg)
243{
244	reg &= 0x1fff;
245
246	/* sign extend register */
247	if (reg & 0x1000)
248		reg |= 0xf000;
249
250	/* convert from 0.0625 to 0.001 resolution */
251	return reg * 125 / 2;
252}
253
254/* sysfs stuff */
255
256/* read routines for temperature limits */
257#define show(value)	\
258static ssize_t show_##value(struct device *dev,				\
259			    struct device_attribute *attr,		\
260			    char *buf)					\
261{									\
262	struct jc42_data *data = jc42_update_device(dev);		\
263	if (IS_ERR(data))						\
264		return PTR_ERR(data);					\
265	return sprintf(buf, "%d\n", jc42_temp_from_reg(data->value));	\
266}
267
268show(temp_input);
269show(temp_crit);
270show(temp_min);
271show(temp_max);
272
273/* read routines for hysteresis values */
274static ssize_t show_temp_crit_hyst(struct device *dev,
275				   struct device_attribute *attr, char *buf)
276{
277	struct jc42_data *data = jc42_update_device(dev);
278	int temp, hyst;
 
 
279
280	if (IS_ERR(data))
281		return PTR_ERR(data);
282
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);
 
 
 
 
 
 
 
 
 
 
 
287}
288
289static ssize_t show_temp_max_hyst(struct device *dev,
290				  struct device_attribute *attr, char *buf)
291{
292	struct jc42_data *data = jc42_update_device(dev);
293	int temp, hyst;
294
295	if (IS_ERR(data))
296		return PTR_ERR(data);
297
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);
302}
303
304/* write routines */
305#define set(value, reg)	\
306static ssize_t set_##value(struct device *dev,				\
307			   struct device_attribute *attr,		\
308			   const char *buf, size_t count)		\
309{									\
310	struct i2c_client *client = to_i2c_client(dev);			\
311	struct jc42_data *data = i2c_get_clientdata(client);		\
312	int err, ret = count;						\
313	long val;							\
314	if (strict_strtol(buf, 10, &val) < 0)				\
315		return -EINVAL;						\
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);		\
319	if (err < 0)							\
320		ret = err;						\
321	mutex_unlock(&data->update_lock);				\
322	return ret;							\
323}
324
325set(temp_min, JC42_REG_TEMP_LOWER);
326set(temp_max, JC42_REG_TEMP_UPPER);
327set(temp_crit, JC42_REG_TEMP_CRITICAL);
328
329/* JC42.4 compliant chips only support four hysteresis values.
330 * Pick best choice and go from there. */
331static ssize_t set_temp_crit_hyst(struct device *dev,
332				  struct device_attribute *attr,
333				  const char *buf, size_t count)
 
 
 
 
 
334{
335	struct i2c_client *client = to_i2c_client(dev);
336	struct jc42_data *data = i2c_get_clientdata(client);
337	unsigned long val;
338	int diff, hyst;
339	int err;
340	int ret = count;
341
342	if (strict_strtoul(buf, 10, &val) < 0)
343		return -EINVAL;
344
345	diff = jc42_temp_from_reg(data->temp_crit) - val;
346	hyst = 0;
347	if (diff > 0) {
348		if (diff < 2250)
349			hyst = 1;	/* 1.5 degrees C */
350		else if (diff < 4500)
351			hyst = 2;	/* 3.0 degrees C */
352		else
353			hyst = 3;	/* 6.0 degrees C */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
354	}
355
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);
361	if (err < 0)
362		ret = err;
363	mutex_unlock(&data->update_lock);
 
364	return ret;
365}
366
367static ssize_t show_alarm(struct device *dev,
368			  struct device_attribute *attr, char *buf)
369{
370	u16 bit = to_sensor_dev_attr(attr)->index;
371	struct jc42_data *data = jc42_update_device(dev);
372	u16 val;
373
374	if (IS_ERR(data))
375		return PTR_ERR(data);
376
377	val = data->temp_input;
378	if (bit != JC42_ALARM_CRIT_BIT && (data->config & JC42_CFG_CRIT_ONLY))
379		val = 0;
380	return sprintf(buf, "%u\n", (val >> bit) & 1);
381}
382
383static DEVICE_ATTR(temp1_input, S_IRUGO,
384		   show_temp_input, NULL);
385static DEVICE_ATTR(temp1_crit, S_IRUGO,
386		   show_temp_crit, set_temp_crit);
387static DEVICE_ATTR(temp1_min, S_IRUGO,
388		   show_temp_min, set_temp_min);
389static DEVICE_ATTR(temp1_max, S_IRUGO,
390		   show_temp_max, set_temp_max);
391
392static DEVICE_ATTR(temp1_crit_hyst, S_IRUGO,
393		   show_temp_crit_hyst, set_temp_crit_hyst);
394static DEVICE_ATTR(temp1_max_hyst, S_IRUGO,
395		   show_temp_max_hyst, NULL);
396
397static SENSOR_DEVICE_ATTR(temp1_crit_alarm, S_IRUGO, show_alarm, NULL,
398			  JC42_ALARM_CRIT_BIT);
399static SENSOR_DEVICE_ATTR(temp1_min_alarm, S_IRUGO, show_alarm, NULL,
400			  JC42_ALARM_MIN_BIT);
401static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_alarm, NULL,
402			  JC42_ALARM_MAX_BIT);
403
404static 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,
414	NULL
415};
416
417static mode_t jc42_attribute_mode(struct kobject *kobj,
418				  struct attribute *attr, int index)
419{
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;
424	bool readonly;
425
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);
433	else
434		readonly = true;
435
436	return S_IRUGO | (readonly ? 0 : S_IWUSR);
437}
438
439static const struct attribute_group jc42_group = {
440	.attrs = jc42_attributes,
441	.is_visible = jc42_attribute_mode,
442};
 
 
 
 
 
 
 
 
 
443
444/* Return 0 if detection is successful, -ENODEV otherwise */
445static int jc42_detect(struct i2c_client *new_client,
446		       struct i2c_board_info *info)
447{
448	struct i2c_adapter *adapter = new_client->adapter;
449	int i, config, cap, manid, devid;
450
451	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA |
452				     I2C_FUNC_SMBUS_WORD_DATA))
453		return -ENODEV;
454
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);
459
460	if (cap < 0 || config < 0 || manid < 0 || devid < 0)
461		return -ENODEV;
462
463	if ((cap & 0xff00) || (config & 0xf800))
464		return -ENODEV;
465
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);
471			return 0;
472		}
473	}
474	return -ENODEV;
475}
476
477static int jc42_probe(struct i2c_client *new_client,
478		      const struct i2c_device_id *id)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
479{
 
 
480	struct jc42_data *data;
481	int config, cap, err;
482
483	data = kzalloc(sizeof(struct jc42_data), GFP_KERNEL);
484	if (!data) {
485		err = -ENOMEM;
486		goto exit;
487	}
488
489	i2c_set_clientdata(new_client, data);
 
490	mutex_init(&data->update_lock);
491
492	cap = jc42_read_value(new_client, JC42_REG_CAP);
493	if (cap < 0) {
494		err = -EINVAL;
495		goto exit_free;
496	}
497	data->extended = !!(cap & JC42_CAP_RANGE);
498
499	config = jc42_read_value(new_client, JC42_REG_CONFIG);
500	if (config < 0) {
501		err = -EINVAL;
502		goto exit_free;
 
 
 
 
 
 
 
 
 
 
503	}
 
 
 
 
 
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);
508	}
509	data->config = config;
510
511	/* Register sysfs hooks */
512	err = sysfs_create_group(&new_client->dev.kobj, &jc42_group);
513	if (err)
514		goto exit_free;
515
516	data->hwmon_dev = hwmon_device_register(&new_client->dev);
517	if (IS_ERR(data->hwmon_dev)) {
518		err = PTR_ERR(data->hwmon_dev);
519		goto exit_remove;
520	}
521
522	return 0;
523
524exit_remove:
525	sysfs_remove_group(&new_client->dev.kobj, &jc42_group);
526exit_free:
527	kfree(data);
528exit:
529	return err;
530}
531
532static int jc42_remove(struct i2c_client *client)
533{
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);
539	kfree(data);
 
 
 
 
 
540	return 0;
541}
542
543/* All registers are word-sized. */
544static int jc42_read_value(struct i2c_client *client, u8 reg)
545{
546	int ret = i2c_smbus_read_word_data(client, reg);
547	if (ret < 0)
548		return ret;
549	return swab16(ret);
550}
551
552static int jc42_write_value(struct i2c_client *client, u8 reg, u16 value)
553{
554	return i2c_smbus_write_word_data(client, reg, swab16(value));
 
 
 
 
 
555}
556
557static struct jc42_data *jc42_update_device(struct device *dev)
558{
559	struct i2c_client *client = to_i2c_client(dev);
560	struct jc42_data *data = i2c_get_clientdata(client);
561	struct jc42_data *ret = data;
562	int val;
563
564	mutex_lock(&data->update_lock);
565
566	if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
567		val = jc42_read_value(client, JC42_REG_TEMP);
568		if (val < 0) {
569			ret = ERR_PTR(val);
570			goto abort;
571		}
572		data->temp_input = val;
573
574		val = jc42_read_value(client, JC42_REG_TEMP_CRITICAL);
575		if (val < 0) {
576			ret = ERR_PTR(val);
577			goto abort;
578		}
579		data->temp_crit = val;
580
581		val = jc42_read_value(client, JC42_REG_TEMP_LOWER);
582		if (val < 0) {
583			ret = ERR_PTR(val);
584			goto abort;
585		}
586		data->temp_min = val;
587
588		val = jc42_read_value(client, JC42_REG_TEMP_UPPER);
589		if (val < 0) {
590			ret = ERR_PTR(val);
591			goto abort;
592		}
593		data->temp_max = val;
594
595		data->last_updated = jiffies;
596		data->valid = true;
597	}
598abort:
599	mutex_unlock(&data->update_lock);
600	return ret;
601}
602
603static int __init sensors_jc42_init(void)
604{
605	return i2c_add_driver(&jc42_driver);
606}
 
 
 
 
 
 
 
 
 
607
608static void __exit sensors_jc42_exit(void)
609{
610	i2c_del_driver(&jc42_driver);
611}
612
613MODULE_AUTHOR("Guenter Roeck <guenter.roeck@ericsson.com>");
614MODULE_DESCRIPTION("JC42 driver");
615MODULE_LICENSE("GPL");
616
617module_init(sensors_jc42_init);
618module_exit(sensors_jc42_exit);
v5.14.15
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * jc42.c - driver for Jedec JC42.4 compliant temperature sensors
  4 *
  5 * Copyright (c) 2010  Ericsson AB.
  6 *
  7 * Derived from lm77.c by Andras BALI <drewie@freemail.hu>.
  8 *
  9 * JC42.4 compliant temperature sensors are typically used on memory modules.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 10 */
 11
 12#include <linux/bitops.h>
 13#include <linux/module.h>
 14#include <linux/init.h>
 15#include <linux/slab.h>
 16#include <linux/jiffies.h>
 17#include <linux/i2c.h>
 18#include <linux/hwmon.h>
 
 19#include <linux/err.h>
 20#include <linux/mutex.h>
 21#include <linux/of.h>
 22
 23/* Addresses to scan */
 24static const unsigned short normal_i2c[] = {
 25	0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, I2C_CLIENT_END };
 26
 27/* JC42 registers. All registers are 16 bit. */
 28#define JC42_REG_CAP		0x00
 29#define JC42_REG_CONFIG		0x01
 30#define JC42_REG_TEMP_UPPER	0x02
 31#define JC42_REG_TEMP_LOWER	0x03
 32#define JC42_REG_TEMP_CRITICAL	0x04
 33#define JC42_REG_TEMP		0x05
 34#define JC42_REG_MANID		0x06
 35#define JC42_REG_DEVICEID	0x07
 36#define JC42_REG_SMBUS		0x22 /* NXP and Atmel, possibly others? */
 37
 38/* Status bits in temperature register */
 39#define JC42_ALARM_CRIT_BIT	15
 40#define JC42_ALARM_MAX_BIT	14
 41#define JC42_ALARM_MIN_BIT	13
 42
 43/* Configuration register defines */
 44#define JC42_CFG_CRIT_ONLY	(1 << 2)
 45#define JC42_CFG_TCRIT_LOCK	(1 << 6)
 46#define JC42_CFG_EVENT_LOCK	(1 << 7)
 47#define JC42_CFG_SHUTDOWN	(1 << 8)
 48#define JC42_CFG_HYST_SHIFT	9
 49#define JC42_CFG_HYST_MASK	(0x03 << 9)
 50
 51/* Capabilities */
 52#define JC42_CAP_RANGE		(1 << 2)
 53
 54/* Manufacturer IDs */
 55#define ADT_MANID		0x11d4  /* Analog Devices */
 56#define ATMEL_MANID		0x001f  /* Atmel */
 57#define ATMEL_MANID2		0x1114	/* Atmel */
 58#define MAX_MANID		0x004d  /* Maxim */
 59#define IDT_MANID		0x00b3  /* IDT */
 60#define MCP_MANID		0x0054  /* Microchip */
 61#define NXP_MANID		0x1131  /* NXP Semiconductors */
 62#define ONS_MANID		0x1b09  /* ON Semiconductor */
 63#define STM_MANID		0x104a  /* ST Microelectronics */
 64#define GT_MANID		0x1c68	/* Giantec */
 65#define GT_MANID2		0x132d	/* Giantec, 2nd mfg ID */
 66
 67/* SMBUS register */
 68#define SMBUS_STMOUT		BIT(7)  /* SMBus time-out, active low */
 69
 70/* Supported chips */
 71
 72/* Analog Devices */
 73#define ADT7408_DEVID		0x0801
 74#define ADT7408_DEVID_MASK	0xffff
 75
 76/* Atmel */
 77#define AT30TS00_DEVID		0x8201
 78#define AT30TS00_DEVID_MASK	0xffff
 79
 80#define AT30TSE004_DEVID	0x2200
 81#define AT30TSE004_DEVID_MASK	0xffff
 82
 83/* Giantec */
 84#define GT30TS00_DEVID		0x2200
 85#define GT30TS00_DEVID_MASK	0xff00
 86
 87#define GT34TS02_DEVID		0x3300
 88#define GT34TS02_DEVID_MASK	0xff00
 89
 90/* IDT */
 91#define TSE2004_DEVID		0x2200
 92#define TSE2004_DEVID_MASK	0xff00
 93
 94#define TS3000_DEVID		0x2900  /* Also matches TSE2002 */
 95#define TS3000_DEVID_MASK	0xff00
 96
 97#define TS3001_DEVID		0x3000
 98#define TS3001_DEVID_MASK	0xff00
 99
100/* Maxim */
101#define MAX6604_DEVID		0x3e00
102#define MAX6604_DEVID_MASK	0xffff
103
104/* Microchip */
105#define MCP9804_DEVID		0x0200
106#define MCP9804_DEVID_MASK	0xfffc
107
108#define MCP9808_DEVID		0x0400
109#define MCP9808_DEVID_MASK	0xfffc
110
111#define MCP98242_DEVID		0x2000
112#define MCP98242_DEVID_MASK	0xfffc
113
114#define MCP98243_DEVID		0x2100
115#define MCP98243_DEVID_MASK	0xfffc
116
117#define MCP98244_DEVID		0x2200
118#define MCP98244_DEVID_MASK	0xfffc
119
120#define MCP9843_DEVID		0x0000	/* Also matches mcp9805 */
121#define MCP9843_DEVID_MASK	0xfffe
122
123/* NXP */
124#define SE97_DEVID		0xa200
125#define SE97_DEVID_MASK		0xfffc
126
127#define SE98_DEVID		0xa100
128#define SE98_DEVID_MASK		0xfffc
129
130/* ON Semiconductor */
131#define CAT6095_DEVID		0x0800	/* Also matches CAT34TS02 */
132#define CAT6095_DEVID_MASK	0xffe0
133
134#define CAT34TS02C_DEVID	0x0a00
135#define CAT34TS02C_DEVID_MASK	0xfff0
136
137#define CAT34TS04_DEVID		0x2200
138#define CAT34TS04_DEVID_MASK	0xfff0
139
140/* ST Microelectronics */
141#define STTS424_DEVID		0x0101
142#define STTS424_DEVID_MASK	0xffff
143
144#define STTS424E_DEVID		0x0000
145#define STTS424E_DEVID_MASK	0xfffe
146
147#define STTS2002_DEVID		0x0300
148#define STTS2002_DEVID_MASK	0xffff
149
150#define STTS2004_DEVID		0x2201
151#define STTS2004_DEVID_MASK	0xffff
152
153#define STTS3000_DEVID		0x0200
154#define STTS3000_DEVID_MASK	0xffff
155
156static u16 jc42_hysteresis[] = { 0, 1500, 3000, 6000 };
157
158struct jc42_chips {
159	u16 manid;
160	u16 devid;
161	u16 devid_mask;
162};
163
164static struct jc42_chips jc42_chips[] = {
165	{ ADT_MANID, ADT7408_DEVID, ADT7408_DEVID_MASK },
166	{ ATMEL_MANID, AT30TS00_DEVID, AT30TS00_DEVID_MASK },
167	{ ATMEL_MANID2, AT30TSE004_DEVID, AT30TSE004_DEVID_MASK },
168	{ GT_MANID, GT30TS00_DEVID, GT30TS00_DEVID_MASK },
169	{ GT_MANID2, GT34TS02_DEVID, GT34TS02_DEVID_MASK },
170	{ IDT_MANID, TSE2004_DEVID, TSE2004_DEVID_MASK },
171	{ IDT_MANID, TS3000_DEVID, TS3000_DEVID_MASK },
172	{ IDT_MANID, TS3001_DEVID, TS3001_DEVID_MASK },
173	{ MAX_MANID, MAX6604_DEVID, MAX6604_DEVID_MASK },
174	{ MCP_MANID, MCP9804_DEVID, MCP9804_DEVID_MASK },
175	{ MCP_MANID, MCP9808_DEVID, MCP9808_DEVID_MASK },
176	{ MCP_MANID, MCP98242_DEVID, MCP98242_DEVID_MASK },
177	{ MCP_MANID, MCP98243_DEVID, MCP98243_DEVID_MASK },
178	{ MCP_MANID, MCP98244_DEVID, MCP98244_DEVID_MASK },
179	{ MCP_MANID, MCP9843_DEVID, MCP9843_DEVID_MASK },
180	{ NXP_MANID, SE97_DEVID, SE97_DEVID_MASK },
181	{ ONS_MANID, CAT6095_DEVID, CAT6095_DEVID_MASK },
182	{ ONS_MANID, CAT34TS02C_DEVID, CAT34TS02C_DEVID_MASK },
183	{ ONS_MANID, CAT34TS04_DEVID, CAT34TS04_DEVID_MASK },
184	{ NXP_MANID, SE98_DEVID, SE98_DEVID_MASK },
185	{ STM_MANID, STTS424_DEVID, STTS424_DEVID_MASK },
186	{ STM_MANID, STTS424E_DEVID, STTS424E_DEVID_MASK },
187	{ STM_MANID, STTS2002_DEVID, STTS2002_DEVID_MASK },
188	{ STM_MANID, STTS2004_DEVID, STTS2004_DEVID_MASK },
189	{ STM_MANID, STTS3000_DEVID, STTS3000_DEVID_MASK },
190};
191
192enum temp_index {
193	t_input = 0,
194	t_crit,
195	t_min,
196	t_max,
197	t_num_temp
198};
199
200static const u8 temp_regs[t_num_temp] = {
201	[t_input] = JC42_REG_TEMP,
202	[t_crit] = JC42_REG_TEMP_CRITICAL,
203	[t_min] = JC42_REG_TEMP_LOWER,
204	[t_max] = JC42_REG_TEMP_UPPER,
205};
206
207/* Each client has this additional data */
208struct jc42_data {
209	struct i2c_client *client;
210	struct mutex	update_lock;	/* protect register access */
211	bool		extended;	/* true if extended range supported */
212	bool		valid;
213	unsigned long	last_updated;	/* In jiffies */
214	u16		orig_config;	/* original configuration */
215	u16		config;		/* current configuration */
216	u16		temp[t_num_temp];/* Temperatures */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
217};
218
219#define JC42_TEMP_MIN_EXTENDED	(-40000)
220#define JC42_TEMP_MIN		0
221#define JC42_TEMP_MAX		125000
222
223static u16 jc42_temp_to_reg(long temp, bool extended)
224{
225	int ntemp = clamp_val(temp,
226			      extended ? JC42_TEMP_MIN_EXTENDED :
227			      JC42_TEMP_MIN, JC42_TEMP_MAX);
228
229	/* convert from 0.001 to 0.0625 resolution */
230	return (ntemp * 2 / 125) & 0x1fff;
231}
232
233static int jc42_temp_from_reg(s16 reg)
234{
235	reg = sign_extend32(reg, 12);
 
 
 
 
236
237	/* convert from 0.0625 to 0.001 resolution */
238	return reg * 125 / 2;
239}
240
241static struct jc42_data *jc42_update_device(struct device *dev)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
242{
243	struct jc42_data *data = dev_get_drvdata(dev);
244	struct i2c_client *client = data->client;
245	struct jc42_data *ret = data;
246	int i, val;
247
248	mutex_lock(&data->update_lock);
 
249
250	if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
251		for (i = 0; i < t_num_temp; i++) {
252			val = i2c_smbus_read_word_swapped(client, temp_regs[i]);
253			if (val < 0) {
254				ret = ERR_PTR(val);
255				goto abort;
256			}
257			data->temp[i] = val;
258		}
259		data->last_updated = jiffies;
260		data->valid = true;
261	}
262abort:
263	mutex_unlock(&data->update_lock);
264	return ret;
265}
266
267static int jc42_read(struct device *dev, enum hwmon_sensor_types type,
268		     u32 attr, int channel, long *val)
269{
270	struct jc42_data *data = jc42_update_device(dev);
271	int temp, hyst;
272
273	if (IS_ERR(data))
274		return PTR_ERR(data);
275
276	switch (attr) {
277	case hwmon_temp_input:
278		*val = jc42_temp_from_reg(data->temp[t_input]);
279		return 0;
280	case hwmon_temp_min:
281		*val = jc42_temp_from_reg(data->temp[t_min]);
282		return 0;
283	case hwmon_temp_max:
284		*val = jc42_temp_from_reg(data->temp[t_max]);
285		return 0;
286	case hwmon_temp_crit:
287		*val = jc42_temp_from_reg(data->temp[t_crit]);
288		return 0;
289	case hwmon_temp_max_hyst:
290		temp = jc42_temp_from_reg(data->temp[t_max]);
291		hyst = jc42_hysteresis[(data->config & JC42_CFG_HYST_MASK)
292						>> JC42_CFG_HYST_SHIFT];
293		*val = temp - hyst;
294		return 0;
295	case hwmon_temp_crit_hyst:
296		temp = jc42_temp_from_reg(data->temp[t_crit]);
297		hyst = jc42_hysteresis[(data->config & JC42_CFG_HYST_MASK)
298						>> JC42_CFG_HYST_SHIFT];
299		*val = temp - hyst;
300		return 0;
301	case hwmon_temp_min_alarm:
302		*val = (data->temp[t_input] >> JC42_ALARM_MIN_BIT) & 1;
303		return 0;
304	case hwmon_temp_max_alarm:
305		*val = (data->temp[t_input] >> JC42_ALARM_MAX_BIT) & 1;
306		return 0;
307	case hwmon_temp_crit_alarm:
308		*val = (data->temp[t_input] >> JC42_ALARM_CRIT_BIT) & 1;
309		return 0;
310	default:
311		return -EOPNOTSUPP;
312	}
313}
314
315static int jc42_write(struct device *dev, enum hwmon_sensor_types type,
316		      u32 attr, int channel, long val)
317{
318	struct jc42_data *data = dev_get_drvdata(dev);
319	struct i2c_client *client = data->client;
 
320	int diff, hyst;
321	int ret;
 
322
323	mutex_lock(&data->update_lock);
 
324
325	switch (attr) {
326	case hwmon_temp_min:
327		data->temp[t_min] = jc42_temp_to_reg(val, data->extended);
328		ret = i2c_smbus_write_word_swapped(client, temp_regs[t_min],
329						   data->temp[t_min]);
330		break;
331	case hwmon_temp_max:
332		data->temp[t_max] = jc42_temp_to_reg(val, data->extended);
333		ret = i2c_smbus_write_word_swapped(client, temp_regs[t_max],
334						   data->temp[t_max]);
335		break;
336	case hwmon_temp_crit:
337		data->temp[t_crit] = jc42_temp_to_reg(val, data->extended);
338		ret = i2c_smbus_write_word_swapped(client, temp_regs[t_crit],
339						   data->temp[t_crit]);
340		break;
341	case hwmon_temp_crit_hyst:
342		/*
343		 * JC42.4 compliant chips only support four hysteresis values.
344		 * Pick best choice and go from there.
345		 */
346		val = clamp_val(val, (data->extended ? JC42_TEMP_MIN_EXTENDED
347						     : JC42_TEMP_MIN) - 6000,
348				JC42_TEMP_MAX);
349		diff = jc42_temp_from_reg(data->temp[t_crit]) - val;
350		hyst = 0;
351		if (diff > 0) {
352			if (diff < 2250)
353				hyst = 1;	/* 1.5 degrees C */
354			else if (diff < 4500)
355				hyst = 2;	/* 3.0 degrees C */
356			else
357				hyst = 3;	/* 6.0 degrees C */
358		}
359		data->config = (data->config & ~JC42_CFG_HYST_MASK) |
360				(hyst << JC42_CFG_HYST_SHIFT);
361		ret = i2c_smbus_write_word_swapped(data->client,
362						   JC42_REG_CONFIG,
363						   data->config);
364		break;
365	default:
366		ret = -EOPNOTSUPP;
367		break;
368	}
369
 
 
 
 
 
 
 
370	mutex_unlock(&data->update_lock);
371
372	return ret;
373}
374
375static umode_t jc42_is_visible(const void *_data, enum hwmon_sensor_types type,
376			       u32 attr, int channel)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
377{
378	const struct jc42_data *data = _data;
 
 
379	unsigned int config = data->config;
380	umode_t mode = 0444;
381
382	switch (attr) {
383	case hwmon_temp_min:
384	case hwmon_temp_max:
385		if (!(config & JC42_CFG_EVENT_LOCK))
386			mode |= 0200;
387		break;
388	case hwmon_temp_crit:
389		if (!(config & JC42_CFG_TCRIT_LOCK))
390			mode |= 0200;
391		break;
392	case hwmon_temp_crit_hyst:
393		if (!(config & (JC42_CFG_EVENT_LOCK | JC42_CFG_TCRIT_LOCK)))
394			mode |= 0200;
395		break;
396	case hwmon_temp_input:
397	case hwmon_temp_max_hyst:
398	case hwmon_temp_min_alarm:
399	case hwmon_temp_max_alarm:
400	case hwmon_temp_crit_alarm:
401		break;
402	default:
403		mode = 0;
404		break;
405	}
406	return mode;
407}
408
409/* Return 0 if detection is successful, -ENODEV otherwise */
410static int jc42_detect(struct i2c_client *client, struct i2c_board_info *info)
 
411{
412	struct i2c_adapter *adapter = client->adapter;
413	int i, config, cap, manid, devid;
414
415	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA |
416				     I2C_FUNC_SMBUS_WORD_DATA))
417		return -ENODEV;
418
419	cap = i2c_smbus_read_word_swapped(client, JC42_REG_CAP);
420	config = i2c_smbus_read_word_swapped(client, JC42_REG_CONFIG);
421	manid = i2c_smbus_read_word_swapped(client, JC42_REG_MANID);
422	devid = i2c_smbus_read_word_swapped(client, JC42_REG_DEVICEID);
423
424	if (cap < 0 || config < 0 || manid < 0 || devid < 0)
425		return -ENODEV;
426
427	if ((cap & 0xff00) || (config & 0xf800))
428		return -ENODEV;
429
430	for (i = 0; i < ARRAY_SIZE(jc42_chips); i++) {
431		struct jc42_chips *chip = &jc42_chips[i];
432		if (manid == chip->manid &&
433		    (devid & chip->devid_mask) == chip->devid) {
434			strlcpy(info->type, "jc42", I2C_NAME_SIZE);
435			return 0;
436		}
437	}
438	return -ENODEV;
439}
440
441static const struct hwmon_channel_info *jc42_info[] = {
442	HWMON_CHANNEL_INFO(temp,
443			   HWMON_T_INPUT | HWMON_T_MIN | HWMON_T_MAX |
444			   HWMON_T_CRIT | HWMON_T_MAX_HYST |
445			   HWMON_T_CRIT_HYST | HWMON_T_MIN_ALARM |
446			   HWMON_T_MAX_ALARM | HWMON_T_CRIT_ALARM),
447	NULL
448};
449
450static const struct hwmon_ops jc42_hwmon_ops = {
451	.is_visible = jc42_is_visible,
452	.read = jc42_read,
453	.write = jc42_write,
454};
455
456static const struct hwmon_chip_info jc42_chip_info = {
457	.ops = &jc42_hwmon_ops,
458	.info = jc42_info,
459};
460
461static int jc42_probe(struct i2c_client *client)
462{
463	struct device *dev = &client->dev;
464	struct device *hwmon_dev;
465	struct jc42_data *data;
466	int config, cap;
467
468	data = devm_kzalloc(dev, sizeof(struct jc42_data), GFP_KERNEL);
469	if (!data)
470		return -ENOMEM;
 
 
471
472	data->client = client;
473	i2c_set_clientdata(client, data);
474	mutex_init(&data->update_lock);
475
476	cap = i2c_smbus_read_word_swapped(client, JC42_REG_CAP);
477	if (cap < 0)
478		return cap;
479
 
480	data->extended = !!(cap & JC42_CAP_RANGE);
481
482	if (device_property_read_bool(dev, "smbus-timeout-disable")) {
483		int smbus;
484
485		/*
486		 * Not all chips support this register, but from a
487		 * quick read of various datasheets no chip appears
488		 * incompatible with the below attempt to disable
489		 * the timeout. And the whole thing is opt-in...
490		 */
491		smbus = i2c_smbus_read_word_swapped(client, JC42_REG_SMBUS);
492		if (smbus < 0)
493			return smbus;
494		i2c_smbus_write_word_swapped(client, JC42_REG_SMBUS,
495					     smbus | SMBUS_STMOUT);
496	}
497
498	config = i2c_smbus_read_word_swapped(client, JC42_REG_CONFIG);
499	if (config < 0)
500		return config;
501
502	data->orig_config = config;
503	if (config & JC42_CFG_SHUTDOWN) {
504		config &= ~JC42_CFG_SHUTDOWN;
505		i2c_smbus_write_word_swapped(client, JC42_REG_CONFIG, config);
506	}
507	data->config = config;
508
509	hwmon_dev = devm_hwmon_device_register_with_info(dev, "jc42",
510							 data, &jc42_chip_info,
511							 NULL);
512	return PTR_ERR_OR_ZERO(hwmon_dev);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
513}
514
515static int jc42_remove(struct i2c_client *client)
516{
517	struct jc42_data *data = i2c_get_clientdata(client);
518
519	/* Restore original configuration except hysteresis */
520	if ((data->config & ~JC42_CFG_HYST_MASK) !=
521	    (data->orig_config & ~JC42_CFG_HYST_MASK)) {
522		int config;
523
524		config = (data->orig_config & ~JC42_CFG_HYST_MASK)
525		  | (data->config & JC42_CFG_HYST_MASK);
526		i2c_smbus_write_word_swapped(client, JC42_REG_CONFIG, config);
527	}
528	return 0;
529}
530
531#ifdef CONFIG_PM
 
 
 
 
 
 
 
532
533static int jc42_suspend(struct device *dev)
534{
535	struct jc42_data *data = dev_get_drvdata(dev);
536
537	data->config |= JC42_CFG_SHUTDOWN;
538	i2c_smbus_write_word_swapped(data->client, JC42_REG_CONFIG,
539				     data->config);
540	return 0;
541}
542
543static int jc42_resume(struct device *dev)
544{
545	struct jc42_data *data = dev_get_drvdata(dev);
 
 
 
 
 
546
547	data->config &= ~JC42_CFG_SHUTDOWN;
548	i2c_smbus_write_word_swapped(data->client, JC42_REG_CONFIG,
549				     data->config);
550	return 0;
551}
 
 
552
553static const struct dev_pm_ops jc42_dev_pm_ops = {
554	.suspend = jc42_suspend,
555	.resume = jc42_resume,
556};
 
 
557
558#define JC42_DEV_PM_OPS (&jc42_dev_pm_ops)
559#else
560#define JC42_DEV_PM_OPS NULL
561#endif /* CONFIG_PM */
 
 
562
563static const struct i2c_device_id jc42_id[] = {
564	{ "jc42", 0 },
565	{ }
566};
567MODULE_DEVICE_TABLE(i2c, jc42_id);
 
568
569#ifdef CONFIG_OF
570static const struct of_device_id jc42_of_ids[] = {
571	{ .compatible = "jedec,jc-42.4-temp", },
572	{ }
573};
574MODULE_DEVICE_TABLE(of, jc42_of_ids);
575#endif
576
577static struct i2c_driver jc42_driver = {
578	.class		= I2C_CLASS_SPD | I2C_CLASS_HWMON,
579	.driver = {
580		.name	= "jc42",
581		.pm = JC42_DEV_PM_OPS,
582		.of_match_table = of_match_ptr(jc42_of_ids),
583	},
584	.probe_new	= jc42_probe,
585	.remove		= jc42_remove,
586	.id_table	= jc42_id,
587	.detect		= jc42_detect,
588	.address_list	= normal_i2c,
589};
590
591module_i2c_driver(jc42_driver);
 
 
 
592
593MODULE_AUTHOR("Guenter Roeck <linux@roeck-us.net>");
594MODULE_DESCRIPTION("JC42 driver");
595MODULE_LICENSE("GPL");