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v5.9
  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, const struct i2c_device_id *id)
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		= 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");
v4.17
 
  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/bitops.h>
 26#include <linux/module.h>
 27#include <linux/init.h>
 28#include <linux/slab.h>
 29#include <linux/jiffies.h>
 30#include <linux/i2c.h>
 31#include <linux/hwmon.h>
 32#include <linux/err.h>
 33#include <linux/mutex.h>
 34#include <linux/of.h>
 35
 36/* Addresses to scan */
 37static const unsigned short normal_i2c[] = {
 38	0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, I2C_CLIENT_END };
 39
 40/* JC42 registers. All registers are 16 bit. */
 41#define JC42_REG_CAP		0x00
 42#define JC42_REG_CONFIG		0x01
 43#define JC42_REG_TEMP_UPPER	0x02
 44#define JC42_REG_TEMP_LOWER	0x03
 45#define JC42_REG_TEMP_CRITICAL	0x04
 46#define JC42_REG_TEMP		0x05
 47#define JC42_REG_MANID		0x06
 48#define JC42_REG_DEVICEID	0x07
 49#define JC42_REG_SMBUS		0x22 /* NXP and Atmel, possibly others? */
 50
 51/* Status bits in temperature register */
 52#define JC42_ALARM_CRIT_BIT	15
 53#define JC42_ALARM_MAX_BIT	14
 54#define JC42_ALARM_MIN_BIT	13
 55
 56/* Configuration register defines */
 57#define JC42_CFG_CRIT_ONLY	(1 << 2)
 58#define JC42_CFG_TCRIT_LOCK	(1 << 6)
 59#define JC42_CFG_EVENT_LOCK	(1 << 7)
 60#define JC42_CFG_SHUTDOWN	(1 << 8)
 61#define JC42_CFG_HYST_SHIFT	9
 62#define JC42_CFG_HYST_MASK	(0x03 << 9)
 63
 64/* Capabilities */
 65#define JC42_CAP_RANGE		(1 << 2)
 66
 67/* Manufacturer IDs */
 68#define ADT_MANID		0x11d4  /* Analog Devices */
 69#define ATMEL_MANID		0x001f  /* Atmel */
 70#define ATMEL_MANID2		0x1114	/* Atmel */
 71#define MAX_MANID		0x004d  /* Maxim */
 72#define IDT_MANID		0x00b3  /* IDT */
 73#define MCP_MANID		0x0054  /* Microchip */
 74#define NXP_MANID		0x1131  /* NXP Semiconductors */
 75#define ONS_MANID		0x1b09  /* ON Semiconductor */
 76#define STM_MANID		0x104a  /* ST Microelectronics */
 77#define GT_MANID		0x1c68	/* Giantec */
 78#define GT_MANID2		0x132d	/* Giantec, 2nd mfg ID */
 79
 80/* SMBUS register */
 81#define SMBUS_STMOUT		BIT(7)  /* SMBus time-out, active low */
 82
 83/* Supported chips */
 84
 85/* Analog Devices */
 86#define ADT7408_DEVID		0x0801
 87#define ADT7408_DEVID_MASK	0xffff
 88
 89/* Atmel */
 90#define AT30TS00_DEVID		0x8201
 91#define AT30TS00_DEVID_MASK	0xffff
 92
 93#define AT30TSE004_DEVID	0x2200
 94#define AT30TSE004_DEVID_MASK	0xffff
 95
 96/* Giantec */
 97#define GT30TS00_DEVID		0x2200
 98#define GT30TS00_DEVID_MASK	0xff00
 99
100#define GT34TS02_DEVID		0x3300
101#define GT34TS02_DEVID_MASK	0xff00
102
103/* IDT */
104#define TSE2004_DEVID		0x2200
105#define TSE2004_DEVID_MASK	0xff00
106
107#define TS3000_DEVID		0x2900  /* Also matches TSE2002 */
108#define TS3000_DEVID_MASK	0xff00
109
110#define TS3001_DEVID		0x3000
111#define TS3001_DEVID_MASK	0xff00
112
113/* Maxim */
114#define MAX6604_DEVID		0x3e00
115#define MAX6604_DEVID_MASK	0xffff
116
117/* Microchip */
118#define MCP9804_DEVID		0x0200
119#define MCP9804_DEVID_MASK	0xfffc
120
121#define MCP9808_DEVID		0x0400
122#define MCP9808_DEVID_MASK	0xfffc
123
124#define MCP98242_DEVID		0x2000
125#define MCP98242_DEVID_MASK	0xfffc
126
127#define MCP98243_DEVID		0x2100
128#define MCP98243_DEVID_MASK	0xfffc
129
130#define MCP98244_DEVID		0x2200
131#define MCP98244_DEVID_MASK	0xfffc
132
133#define MCP9843_DEVID		0x0000	/* Also matches mcp9805 */
134#define MCP9843_DEVID_MASK	0xfffe
135
136/* NXP */
137#define SE97_DEVID		0xa200
138#define SE97_DEVID_MASK		0xfffc
139
140#define SE98_DEVID		0xa100
141#define SE98_DEVID_MASK		0xfffc
142
143/* ON Semiconductor */
144#define CAT6095_DEVID		0x0800	/* Also matches CAT34TS02 */
145#define CAT6095_DEVID_MASK	0xffe0
146
147#define CAT34TS02C_DEVID	0x0a00
148#define CAT34TS02C_DEVID_MASK	0xfff0
149
150#define CAT34TS04_DEVID		0x2200
151#define CAT34TS04_DEVID_MASK	0xfff0
152
153/* ST Microelectronics */
154#define STTS424_DEVID		0x0101
155#define STTS424_DEVID_MASK	0xffff
156
157#define STTS424E_DEVID		0x0000
158#define STTS424E_DEVID_MASK	0xfffe
159
160#define STTS2002_DEVID		0x0300
161#define STTS2002_DEVID_MASK	0xffff
162
163#define STTS2004_DEVID		0x2201
164#define STTS2004_DEVID_MASK	0xffff
165
166#define STTS3000_DEVID		0x0200
167#define STTS3000_DEVID_MASK	0xffff
168
169static u16 jc42_hysteresis[] = { 0, 1500, 3000, 6000 };
170
171struct jc42_chips {
172	u16 manid;
173	u16 devid;
174	u16 devid_mask;
175};
176
177static struct jc42_chips jc42_chips[] = {
178	{ ADT_MANID, ADT7408_DEVID, ADT7408_DEVID_MASK },
179	{ ATMEL_MANID, AT30TS00_DEVID, AT30TS00_DEVID_MASK },
180	{ ATMEL_MANID2, AT30TSE004_DEVID, AT30TSE004_DEVID_MASK },
181	{ GT_MANID, GT30TS00_DEVID, GT30TS00_DEVID_MASK },
182	{ GT_MANID2, GT34TS02_DEVID, GT34TS02_DEVID_MASK },
183	{ IDT_MANID, TSE2004_DEVID, TSE2004_DEVID_MASK },
184	{ IDT_MANID, TS3000_DEVID, TS3000_DEVID_MASK },
185	{ IDT_MANID, TS3001_DEVID, TS3001_DEVID_MASK },
186	{ MAX_MANID, MAX6604_DEVID, MAX6604_DEVID_MASK },
187	{ MCP_MANID, MCP9804_DEVID, MCP9804_DEVID_MASK },
188	{ MCP_MANID, MCP9808_DEVID, MCP9808_DEVID_MASK },
189	{ MCP_MANID, MCP98242_DEVID, MCP98242_DEVID_MASK },
190	{ MCP_MANID, MCP98243_DEVID, MCP98243_DEVID_MASK },
191	{ MCP_MANID, MCP98244_DEVID, MCP98244_DEVID_MASK },
192	{ MCP_MANID, MCP9843_DEVID, MCP9843_DEVID_MASK },
193	{ NXP_MANID, SE97_DEVID, SE97_DEVID_MASK },
194	{ ONS_MANID, CAT6095_DEVID, CAT6095_DEVID_MASK },
195	{ ONS_MANID, CAT34TS02C_DEVID, CAT34TS02C_DEVID_MASK },
196	{ ONS_MANID, CAT34TS04_DEVID, CAT34TS04_DEVID_MASK },
197	{ NXP_MANID, SE98_DEVID, SE98_DEVID_MASK },
198	{ STM_MANID, STTS424_DEVID, STTS424_DEVID_MASK },
199	{ STM_MANID, STTS424E_DEVID, STTS424E_DEVID_MASK },
200	{ STM_MANID, STTS2002_DEVID, STTS2002_DEVID_MASK },
201	{ STM_MANID, STTS2004_DEVID, STTS2004_DEVID_MASK },
202	{ STM_MANID, STTS3000_DEVID, STTS3000_DEVID_MASK },
203};
204
205enum temp_index {
206	t_input = 0,
207	t_crit,
208	t_min,
209	t_max,
210	t_num_temp
211};
212
213static const u8 temp_regs[t_num_temp] = {
214	[t_input] = JC42_REG_TEMP,
215	[t_crit] = JC42_REG_TEMP_CRITICAL,
216	[t_min] = JC42_REG_TEMP_LOWER,
217	[t_max] = JC42_REG_TEMP_UPPER,
218};
219
220/* Each client has this additional data */
221struct jc42_data {
222	struct i2c_client *client;
223	struct mutex	update_lock;	/* protect register access */
224	bool		extended;	/* true if extended range supported */
225	bool		valid;
226	unsigned long	last_updated;	/* In jiffies */
227	u16		orig_config;	/* original configuration */
228	u16		config;		/* current configuration */
229	u16		temp[t_num_temp];/* Temperatures */
230};
231
232#define JC42_TEMP_MIN_EXTENDED	(-40000)
233#define JC42_TEMP_MIN		0
234#define JC42_TEMP_MAX		125000
235
236static u16 jc42_temp_to_reg(long temp, bool extended)
237{
238	int ntemp = clamp_val(temp,
239			      extended ? JC42_TEMP_MIN_EXTENDED :
240			      JC42_TEMP_MIN, JC42_TEMP_MAX);
241
242	/* convert from 0.001 to 0.0625 resolution */
243	return (ntemp * 2 / 125) & 0x1fff;
244}
245
246static int jc42_temp_from_reg(s16 reg)
247{
248	reg = sign_extend32(reg, 12);
249
250	/* convert from 0.0625 to 0.001 resolution */
251	return reg * 125 / 2;
252}
253
254static struct jc42_data *jc42_update_device(struct device *dev)
255{
256	struct jc42_data *data = dev_get_drvdata(dev);
257	struct i2c_client *client = data->client;
258	struct jc42_data *ret = data;
259	int i, val;
260
261	mutex_lock(&data->update_lock);
262
263	if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
264		for (i = 0; i < t_num_temp; i++) {
265			val = i2c_smbus_read_word_swapped(client, temp_regs[i]);
266			if (val < 0) {
267				ret = ERR_PTR(val);
268				goto abort;
269			}
270			data->temp[i] = val;
271		}
272		data->last_updated = jiffies;
273		data->valid = true;
274	}
275abort:
276	mutex_unlock(&data->update_lock);
277	return ret;
278}
279
280static int jc42_read(struct device *dev, enum hwmon_sensor_types type,
281		     u32 attr, int channel, long *val)
282{
283	struct jc42_data *data = jc42_update_device(dev);
284	int temp, hyst;
285
286	if (IS_ERR(data))
287		return PTR_ERR(data);
288
289	switch (attr) {
290	case hwmon_temp_input:
291		*val = jc42_temp_from_reg(data->temp[t_input]);
292		return 0;
293	case hwmon_temp_min:
294		*val = jc42_temp_from_reg(data->temp[t_min]);
295		return 0;
296	case hwmon_temp_max:
297		*val = jc42_temp_from_reg(data->temp[t_max]);
298		return 0;
299	case hwmon_temp_crit:
300		*val = jc42_temp_from_reg(data->temp[t_crit]);
301		return 0;
302	case hwmon_temp_max_hyst:
303		temp = jc42_temp_from_reg(data->temp[t_max]);
304		hyst = jc42_hysteresis[(data->config & JC42_CFG_HYST_MASK)
305						>> JC42_CFG_HYST_SHIFT];
306		*val = temp - hyst;
307		return 0;
308	case hwmon_temp_crit_hyst:
309		temp = jc42_temp_from_reg(data->temp[t_crit]);
310		hyst = jc42_hysteresis[(data->config & JC42_CFG_HYST_MASK)
311						>> JC42_CFG_HYST_SHIFT];
312		*val = temp - hyst;
313		return 0;
314	case hwmon_temp_min_alarm:
315		*val = (data->temp[t_input] >> JC42_ALARM_MIN_BIT) & 1;
316		return 0;
317	case hwmon_temp_max_alarm:
318		*val = (data->temp[t_input] >> JC42_ALARM_MAX_BIT) & 1;
319		return 0;
320	case hwmon_temp_crit_alarm:
321		*val = (data->temp[t_input] >> JC42_ALARM_CRIT_BIT) & 1;
322		return 0;
323	default:
324		return -EOPNOTSUPP;
325	}
326}
327
328static int jc42_write(struct device *dev, enum hwmon_sensor_types type,
329		      u32 attr, int channel, long val)
330{
331	struct jc42_data *data = dev_get_drvdata(dev);
332	struct i2c_client *client = data->client;
333	int diff, hyst;
334	int ret;
335
336	mutex_lock(&data->update_lock);
337
338	switch (attr) {
339	case hwmon_temp_min:
340		data->temp[t_min] = jc42_temp_to_reg(val, data->extended);
341		ret = i2c_smbus_write_word_swapped(client, temp_regs[t_min],
342						   data->temp[t_min]);
343		break;
344	case hwmon_temp_max:
345		data->temp[t_max] = jc42_temp_to_reg(val, data->extended);
346		ret = i2c_smbus_write_word_swapped(client, temp_regs[t_max],
347						   data->temp[t_max]);
348		break;
349	case hwmon_temp_crit:
350		data->temp[t_crit] = jc42_temp_to_reg(val, data->extended);
351		ret = i2c_smbus_write_word_swapped(client, temp_regs[t_crit],
352						   data->temp[t_crit]);
353		break;
354	case hwmon_temp_crit_hyst:
355		/*
356		 * JC42.4 compliant chips only support four hysteresis values.
357		 * Pick best choice and go from there.
358		 */
359		val = clamp_val(val, (data->extended ? JC42_TEMP_MIN_EXTENDED
360						     : JC42_TEMP_MIN) - 6000,
361				JC42_TEMP_MAX);
362		diff = jc42_temp_from_reg(data->temp[t_crit]) - val;
363		hyst = 0;
364		if (diff > 0) {
365			if (diff < 2250)
366				hyst = 1;	/* 1.5 degrees C */
367			else if (diff < 4500)
368				hyst = 2;	/* 3.0 degrees C */
369			else
370				hyst = 3;	/* 6.0 degrees C */
371		}
372		data->config = (data->config & ~JC42_CFG_HYST_MASK) |
373				(hyst << JC42_CFG_HYST_SHIFT);
374		ret = i2c_smbus_write_word_swapped(data->client,
375						   JC42_REG_CONFIG,
376						   data->config);
377		break;
378	default:
379		ret = -EOPNOTSUPP;
380		break;
381	}
382
383	mutex_unlock(&data->update_lock);
384
385	return ret;
386}
387
388static umode_t jc42_is_visible(const void *_data, enum hwmon_sensor_types type,
389			       u32 attr, int channel)
390{
391	const struct jc42_data *data = _data;
392	unsigned int config = data->config;
393	umode_t mode = S_IRUGO;
394
395	switch (attr) {
396	case hwmon_temp_min:
397	case hwmon_temp_max:
398		if (!(config & JC42_CFG_EVENT_LOCK))
399			mode |= S_IWUSR;
400		break;
401	case hwmon_temp_crit:
402		if (!(config & JC42_CFG_TCRIT_LOCK))
403			mode |= S_IWUSR;
404		break;
405	case hwmon_temp_crit_hyst:
406		if (!(config & (JC42_CFG_EVENT_LOCK | JC42_CFG_TCRIT_LOCK)))
407			mode |= S_IWUSR;
408		break;
409	case hwmon_temp_input:
410	case hwmon_temp_max_hyst:
411	case hwmon_temp_min_alarm:
412	case hwmon_temp_max_alarm:
413	case hwmon_temp_crit_alarm:
414		break;
415	default:
416		mode = 0;
417		break;
418	}
419	return mode;
420}
421
422/* Return 0 if detection is successful, -ENODEV otherwise */
423static int jc42_detect(struct i2c_client *client, struct i2c_board_info *info)
424{
425	struct i2c_adapter *adapter = client->adapter;
426	int i, config, cap, manid, devid;
427
428	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA |
429				     I2C_FUNC_SMBUS_WORD_DATA))
430		return -ENODEV;
431
432	cap = i2c_smbus_read_word_swapped(client, JC42_REG_CAP);
433	config = i2c_smbus_read_word_swapped(client, JC42_REG_CONFIG);
434	manid = i2c_smbus_read_word_swapped(client, JC42_REG_MANID);
435	devid = i2c_smbus_read_word_swapped(client, JC42_REG_DEVICEID);
436
437	if (cap < 0 || config < 0 || manid < 0 || devid < 0)
438		return -ENODEV;
439
440	if ((cap & 0xff00) || (config & 0xf800))
441		return -ENODEV;
442
443	for (i = 0; i < ARRAY_SIZE(jc42_chips); i++) {
444		struct jc42_chips *chip = &jc42_chips[i];
445		if (manid == chip->manid &&
446		    (devid & chip->devid_mask) == chip->devid) {
447			strlcpy(info->type, "jc42", I2C_NAME_SIZE);
448			return 0;
449		}
450	}
451	return -ENODEV;
452}
453
454static const u32 jc42_temp_config[] = {
455	HWMON_T_INPUT | HWMON_T_MIN | HWMON_T_MAX | HWMON_T_CRIT |
456	HWMON_T_MAX_HYST | HWMON_T_CRIT_HYST |
457	HWMON_T_MIN_ALARM | HWMON_T_MAX_ALARM | HWMON_T_CRIT_ALARM,
458	0
459};
460
461static const struct hwmon_channel_info jc42_temp = {
462	.type = hwmon_temp,
463	.config = jc42_temp_config,
464};
465
466static const struct hwmon_channel_info *jc42_info[] = {
467	&jc42_temp,
 
 
 
 
468	NULL
469};
470
471static const struct hwmon_ops jc42_hwmon_ops = {
472	.is_visible = jc42_is_visible,
473	.read = jc42_read,
474	.write = jc42_write,
475};
476
477static const struct hwmon_chip_info jc42_chip_info = {
478	.ops = &jc42_hwmon_ops,
479	.info = jc42_info,
480};
481
482static int jc42_probe(struct i2c_client *client, const struct i2c_device_id *id)
483{
484	struct device *dev = &client->dev;
485	struct device *hwmon_dev;
486	struct jc42_data *data;
487	int config, cap;
488
489	data = devm_kzalloc(dev, sizeof(struct jc42_data), GFP_KERNEL);
490	if (!data)
491		return -ENOMEM;
492
493	data->client = client;
494	i2c_set_clientdata(client, data);
495	mutex_init(&data->update_lock);
496
497	cap = i2c_smbus_read_word_swapped(client, JC42_REG_CAP);
498	if (cap < 0)
499		return cap;
500
501	data->extended = !!(cap & JC42_CAP_RANGE);
502
503	if (device_property_read_bool(dev, "smbus-timeout-disable")) {
504		int smbus;
505
506		/*
507		 * Not all chips support this register, but from a
508		 * quick read of various datasheets no chip appears
509		 * incompatible with the below attempt to disable
510		 * the timeout. And the whole thing is opt-in...
511		 */
512		smbus = i2c_smbus_read_word_swapped(client, JC42_REG_SMBUS);
513		if (smbus < 0)
514			return smbus;
515		i2c_smbus_write_word_swapped(client, JC42_REG_SMBUS,
516					     smbus | SMBUS_STMOUT);
517	}
518
519	config = i2c_smbus_read_word_swapped(client, JC42_REG_CONFIG);
520	if (config < 0)
521		return config;
522
523	data->orig_config = config;
524	if (config & JC42_CFG_SHUTDOWN) {
525		config &= ~JC42_CFG_SHUTDOWN;
526		i2c_smbus_write_word_swapped(client, JC42_REG_CONFIG, config);
527	}
528	data->config = config;
529
530	hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
531							 data, &jc42_chip_info,
532							 NULL);
533	return PTR_ERR_OR_ZERO(hwmon_dev);
534}
535
536static int jc42_remove(struct i2c_client *client)
537{
538	struct jc42_data *data = i2c_get_clientdata(client);
539
540	/* Restore original configuration except hysteresis */
541	if ((data->config & ~JC42_CFG_HYST_MASK) !=
542	    (data->orig_config & ~JC42_CFG_HYST_MASK)) {
543		int config;
544
545		config = (data->orig_config & ~JC42_CFG_HYST_MASK)
546		  | (data->config & JC42_CFG_HYST_MASK);
547		i2c_smbus_write_word_swapped(client, JC42_REG_CONFIG, config);
548	}
549	return 0;
550}
551
552#ifdef CONFIG_PM
553
554static int jc42_suspend(struct device *dev)
555{
556	struct jc42_data *data = dev_get_drvdata(dev);
557
558	data->config |= JC42_CFG_SHUTDOWN;
559	i2c_smbus_write_word_swapped(data->client, JC42_REG_CONFIG,
560				     data->config);
561	return 0;
562}
563
564static int jc42_resume(struct device *dev)
565{
566	struct jc42_data *data = dev_get_drvdata(dev);
567
568	data->config &= ~JC42_CFG_SHUTDOWN;
569	i2c_smbus_write_word_swapped(data->client, JC42_REG_CONFIG,
570				     data->config);
571	return 0;
572}
573
574static const struct dev_pm_ops jc42_dev_pm_ops = {
575	.suspend = jc42_suspend,
576	.resume = jc42_resume,
577};
578
579#define JC42_DEV_PM_OPS (&jc42_dev_pm_ops)
580#else
581#define JC42_DEV_PM_OPS NULL
582#endif /* CONFIG_PM */
583
584static const struct i2c_device_id jc42_id[] = {
585	{ "jc42", 0 },
586	{ }
587};
588MODULE_DEVICE_TABLE(i2c, jc42_id);
589
590#ifdef CONFIG_OF
591static const struct of_device_id jc42_of_ids[] = {
592	{ .compatible = "jedec,jc-42.4-temp", },
593	{ }
594};
595MODULE_DEVICE_TABLE(of, jc42_of_ids);
596#endif
597
598static struct i2c_driver jc42_driver = {
599	.class		= I2C_CLASS_SPD | I2C_CLASS_HWMON,
600	.driver = {
601		.name	= "jc42",
602		.pm = JC42_DEV_PM_OPS,
603		.of_match_table = of_match_ptr(jc42_of_ids),
604	},
605	.probe		= jc42_probe,
606	.remove		= jc42_remove,
607	.id_table	= jc42_id,
608	.detect		= jc42_detect,
609	.address_list	= normal_i2c,
610};
611
612module_i2c_driver(jc42_driver);
613
614MODULE_AUTHOR("Guenter Roeck <linux@roeck-us.net>");
615MODULE_DESCRIPTION("JC42 driver");
616MODULE_LICENSE("GPL");