xref: /openbmc/linux/drivers/hwmon/adm1021.c (revision 8e7a49e0)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * adm1021.c - Part of lm_sensors, Linux kernel modules for hardware
4  *	       monitoring
5  * Copyright (c) 1998, 1999  Frodo Looijaard <frodol@dds.nl> and
6  *			     Philip Edelbrock <phil@netroedge.com>
7  */
8 
9 #include <linux/module.h>
10 #include <linux/init.h>
11 #include <linux/slab.h>
12 #include <linux/jiffies.h>
13 #include <linux/i2c.h>
14 #include <linux/hwmon.h>
15 #include <linux/hwmon-sysfs.h>
16 #include <linux/err.h>
17 #include <linux/mutex.h>
18 
19 
20 /* Addresses to scan */
21 static const unsigned short normal_i2c[] = {
22 	0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b, 0x4c, 0x4d, 0x4e, I2C_CLIENT_END };
23 
24 enum chips {
25 	adm1021, adm1023, max1617, max1617a, thmc10, lm84, gl523sm, mc1066 };
26 
27 /* adm1021 constants specified below */
28 
29 /* The adm1021 registers */
30 /* Read-only */
31 /* For nr in 0-1 */
32 #define ADM1021_REG_TEMP(nr)		(nr)
33 #define ADM1021_REG_STATUS		0x02
34 /* 0x41 = AD, 0x49 = TI, 0x4D = Maxim, 0x23 = Genesys , 0x54 = Onsemi */
35 #define ADM1021_REG_MAN_ID		0xFE
36 /* ADM1021 = 0x0X, ADM1023 = 0x3X */
37 #define ADM1021_REG_DEV_ID		0xFF
38 /* These use different addresses for reading/writing */
39 #define ADM1021_REG_CONFIG_R		0x03
40 #define ADM1021_REG_CONFIG_W		0x09
41 #define ADM1021_REG_CONV_RATE_R		0x04
42 #define ADM1021_REG_CONV_RATE_W		0x0A
43 /* These are for the ADM1023's additional precision on the remote temp sensor */
44 #define ADM1023_REG_REM_TEMP_PREC	0x10
45 #define ADM1023_REG_REM_OFFSET		0x11
46 #define ADM1023_REG_REM_OFFSET_PREC	0x12
47 #define ADM1023_REG_REM_TOS_PREC	0x13
48 #define ADM1023_REG_REM_THYST_PREC	0x14
49 /* limits */
50 /* For nr in 0-1 */
51 #define ADM1021_REG_TOS_R(nr)		(0x05 + 2 * (nr))
52 #define ADM1021_REG_TOS_W(nr)		(0x0B + 2 * (nr))
53 #define ADM1021_REG_THYST_R(nr)		(0x06 + 2 * (nr))
54 #define ADM1021_REG_THYST_W(nr)		(0x0C + 2 * (nr))
55 /* write-only */
56 #define ADM1021_REG_ONESHOT		0x0F
57 
58 /* Initial values */
59 
60 /*
61  * Note: Even though I left the low and high limits named os and hyst,
62  * they don't quite work like a thermostat the way the LM75 does.  I.e.,
63  * a lower temp than THYST actually triggers an alarm instead of
64  * clearing it.  Weird, ey?   --Phil
65  */
66 
67 /* Each client has this additional data */
68 struct adm1021_data {
69 	struct i2c_client *client;
70 	enum chips type;
71 
72 	const struct attribute_group *groups[3];
73 
74 	struct mutex update_lock;
75 	bool valid;		/* true if following fields are valid */
76 	char low_power;		/* !=0 if device in low power mode */
77 	unsigned long last_updated;	/* In jiffies */
78 
79 	int temp_max[2];		/* Register values */
80 	int temp_min[2];
81 	int temp[2];
82 	u8 alarms;
83 	/* Special values for ADM1023 only */
84 	u8 remote_temp_offset;
85 	u8 remote_temp_offset_prec;
86 };
87 
88 /* (amalysh) read only mode, otherwise any limit's writing confuse BIOS */
89 static bool read_only;
90 
91 static struct adm1021_data *adm1021_update_device(struct device *dev)
92 {
93 	struct adm1021_data *data = dev_get_drvdata(dev);
94 	struct i2c_client *client = data->client;
95 
96 	mutex_lock(&data->update_lock);
97 
98 	if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
99 	    || !data->valid) {
100 		int i;
101 
102 		dev_dbg(dev, "Starting adm1021 update\n");
103 
104 		for (i = 0; i < 2; i++) {
105 			data->temp[i] = 1000 *
106 				(s8) i2c_smbus_read_byte_data(
107 					client, ADM1021_REG_TEMP(i));
108 			data->temp_max[i] = 1000 *
109 				(s8) i2c_smbus_read_byte_data(
110 					client, ADM1021_REG_TOS_R(i));
111 			if (data->type != lm84) {
112 				data->temp_min[i] = 1000 *
113 				  (s8) i2c_smbus_read_byte_data(client,
114 							ADM1021_REG_THYST_R(i));
115 			}
116 		}
117 		data->alarms = i2c_smbus_read_byte_data(client,
118 						ADM1021_REG_STATUS) & 0x7c;
119 		if (data->type == adm1023) {
120 			/*
121 			 * The ADM1023 provides 3 extra bits of precision for
122 			 * the remote sensor in extra registers.
123 			 */
124 			data->temp[1] += 125 * (i2c_smbus_read_byte_data(
125 				client, ADM1023_REG_REM_TEMP_PREC) >> 5);
126 			data->temp_max[1] += 125 * (i2c_smbus_read_byte_data(
127 				client, ADM1023_REG_REM_TOS_PREC) >> 5);
128 			data->temp_min[1] += 125 * (i2c_smbus_read_byte_data(
129 				client, ADM1023_REG_REM_THYST_PREC) >> 5);
130 			data->remote_temp_offset =
131 				i2c_smbus_read_byte_data(client,
132 						ADM1023_REG_REM_OFFSET);
133 			data->remote_temp_offset_prec =
134 				i2c_smbus_read_byte_data(client,
135 						ADM1023_REG_REM_OFFSET_PREC);
136 		}
137 		data->last_updated = jiffies;
138 		data->valid = true;
139 	}
140 
141 	mutex_unlock(&data->update_lock);
142 
143 	return data;
144 }
145 
146 static ssize_t temp_show(struct device *dev, struct device_attribute *devattr,
147 			 char *buf)
148 {
149 	int index = to_sensor_dev_attr(devattr)->index;
150 	struct adm1021_data *data = adm1021_update_device(dev);
151 
152 	return sprintf(buf, "%d\n", data->temp[index]);
153 }
154 
155 static ssize_t temp_max_show(struct device *dev,
156 			     struct device_attribute *devattr, char *buf)
157 {
158 	int index = to_sensor_dev_attr(devattr)->index;
159 	struct adm1021_data *data = adm1021_update_device(dev);
160 
161 	return sprintf(buf, "%d\n", data->temp_max[index]);
162 }
163 
164 static ssize_t temp_min_show(struct device *dev,
165 			     struct device_attribute *devattr, char *buf)
166 {
167 	int index = to_sensor_dev_attr(devattr)->index;
168 	struct adm1021_data *data = adm1021_update_device(dev);
169 
170 	return sprintf(buf, "%d\n", data->temp_min[index]);
171 }
172 
173 static ssize_t alarm_show(struct device *dev, struct device_attribute *attr,
174 			  char *buf)
175 {
176 	int index = to_sensor_dev_attr(attr)->index;
177 	struct adm1021_data *data = adm1021_update_device(dev);
178 	return sprintf(buf, "%u\n", (data->alarms >> index) & 1);
179 }
180 
181 static ssize_t alarms_show(struct device *dev,
182 			   struct device_attribute *attr,
183 			   char *buf)
184 {
185 	struct adm1021_data *data = adm1021_update_device(dev);
186 	return sprintf(buf, "%u\n", data->alarms);
187 }
188 
189 static ssize_t temp_max_store(struct device *dev,
190 			      struct device_attribute *devattr,
191 			      const char *buf, size_t count)
192 {
193 	int index = to_sensor_dev_attr(devattr)->index;
194 	struct adm1021_data *data = dev_get_drvdata(dev);
195 	struct i2c_client *client = data->client;
196 	long temp;
197 	int reg_val, err;
198 
199 	err = kstrtol(buf, 10, &temp);
200 	if (err)
201 		return err;
202 	temp /= 1000;
203 
204 	mutex_lock(&data->update_lock);
205 	reg_val = clamp_val(temp, -128, 127);
206 	data->temp_max[index] = reg_val * 1000;
207 	if (!read_only)
208 		i2c_smbus_write_byte_data(client, ADM1021_REG_TOS_W(index),
209 					  reg_val);
210 	mutex_unlock(&data->update_lock);
211 
212 	return count;
213 }
214 
215 static ssize_t temp_min_store(struct device *dev,
216 			      struct device_attribute *devattr,
217 			      const char *buf, size_t count)
218 {
219 	int index = to_sensor_dev_attr(devattr)->index;
220 	struct adm1021_data *data = dev_get_drvdata(dev);
221 	struct i2c_client *client = data->client;
222 	long temp;
223 	int reg_val, err;
224 
225 	err = kstrtol(buf, 10, &temp);
226 	if (err)
227 		return err;
228 	temp /= 1000;
229 
230 	mutex_lock(&data->update_lock);
231 	reg_val = clamp_val(temp, -128, 127);
232 	data->temp_min[index] = reg_val * 1000;
233 	if (!read_only)
234 		i2c_smbus_write_byte_data(client, ADM1021_REG_THYST_W(index),
235 					  reg_val);
236 	mutex_unlock(&data->update_lock);
237 
238 	return count;
239 }
240 
241 static ssize_t low_power_show(struct device *dev,
242 			      struct device_attribute *devattr, char *buf)
243 {
244 	struct adm1021_data *data = adm1021_update_device(dev);
245 	return sprintf(buf, "%d\n", data->low_power);
246 }
247 
248 static ssize_t low_power_store(struct device *dev,
249 			       struct device_attribute *devattr,
250 			       const char *buf, size_t count)
251 {
252 	struct adm1021_data *data = dev_get_drvdata(dev);
253 	struct i2c_client *client = data->client;
254 	char low_power;
255 	unsigned long val;
256 	int err;
257 
258 	err = kstrtoul(buf, 10, &val);
259 	if (err)
260 		return err;
261 	low_power = val != 0;
262 
263 	mutex_lock(&data->update_lock);
264 	if (low_power != data->low_power) {
265 		int config = i2c_smbus_read_byte_data(
266 			client, ADM1021_REG_CONFIG_R);
267 		data->low_power = low_power;
268 		i2c_smbus_write_byte_data(client, ADM1021_REG_CONFIG_W,
269 			(config & 0xBF) | (low_power << 6));
270 	}
271 	mutex_unlock(&data->update_lock);
272 
273 	return count;
274 }
275 
276 
277 static SENSOR_DEVICE_ATTR_RO(temp1_input, temp, 0);
278 static SENSOR_DEVICE_ATTR_RW(temp1_max, temp_max, 0);
279 static SENSOR_DEVICE_ATTR_RW(temp1_min, temp_min, 0);
280 static SENSOR_DEVICE_ATTR_RO(temp2_input, temp, 1);
281 static SENSOR_DEVICE_ATTR_RW(temp2_max, temp_max, 1);
282 static SENSOR_DEVICE_ATTR_RW(temp2_min, temp_min, 1);
283 static SENSOR_DEVICE_ATTR_RO(temp1_max_alarm, alarm, 6);
284 static SENSOR_DEVICE_ATTR_RO(temp1_min_alarm, alarm, 5);
285 static SENSOR_DEVICE_ATTR_RO(temp2_max_alarm, alarm, 4);
286 static SENSOR_DEVICE_ATTR_RO(temp2_min_alarm, alarm, 3);
287 static SENSOR_DEVICE_ATTR_RO(temp2_fault, alarm, 2);
288 
289 static DEVICE_ATTR_RO(alarms);
290 static DEVICE_ATTR_RW(low_power);
291 
292 static struct attribute *adm1021_attributes[] = {
293 	&sensor_dev_attr_temp1_max.dev_attr.attr,
294 	&sensor_dev_attr_temp1_input.dev_attr.attr,
295 	&sensor_dev_attr_temp2_max.dev_attr.attr,
296 	&sensor_dev_attr_temp2_input.dev_attr.attr,
297 	&sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
298 	&sensor_dev_attr_temp2_max_alarm.dev_attr.attr,
299 	&sensor_dev_attr_temp2_fault.dev_attr.attr,
300 	&dev_attr_alarms.attr,
301 	&dev_attr_low_power.attr,
302 	NULL
303 };
304 
305 static const struct attribute_group adm1021_group = {
306 	.attrs = adm1021_attributes,
307 };
308 
309 static struct attribute *adm1021_min_attributes[] = {
310 	&sensor_dev_attr_temp1_min.dev_attr.attr,
311 	&sensor_dev_attr_temp2_min.dev_attr.attr,
312 	&sensor_dev_attr_temp1_min_alarm.dev_attr.attr,
313 	&sensor_dev_attr_temp2_min_alarm.dev_attr.attr,
314 	NULL
315 };
316 
317 static const struct attribute_group adm1021_min_group = {
318 	.attrs = adm1021_min_attributes,
319 };
320 
321 /* Return 0 if detection is successful, -ENODEV otherwise */
322 static int adm1021_detect(struct i2c_client *client,
323 			  struct i2c_board_info *info)
324 {
325 	struct i2c_adapter *adapter = client->adapter;
326 	const char *type_name;
327 	int reg, conv_rate, status, config, man_id, dev_id;
328 
329 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) {
330 		pr_debug("detect failed, smbus byte data not supported!\n");
331 		return -ENODEV;
332 	}
333 
334 	status = i2c_smbus_read_byte_data(client, ADM1021_REG_STATUS);
335 	conv_rate = i2c_smbus_read_byte_data(client,
336 					     ADM1021_REG_CONV_RATE_R);
337 	config = i2c_smbus_read_byte_data(client, ADM1021_REG_CONFIG_R);
338 
339 	/* Check unused bits */
340 	if ((status & 0x03) || (config & 0x3F) || (conv_rate & 0xF8)) {
341 		pr_debug("detect failed, chip not detected!\n");
342 		return -ENODEV;
343 	}
344 
345 	/* Determine the chip type. */
346 	man_id = i2c_smbus_read_byte_data(client, ADM1021_REG_MAN_ID);
347 	dev_id = i2c_smbus_read_byte_data(client, ADM1021_REG_DEV_ID);
348 
349 	if (man_id < 0 || dev_id < 0)
350 		return -ENODEV;
351 
352 	if (man_id == 0x4d && dev_id == 0x01) {
353 		/*
354 		 * dev_id 0x01 matches MAX6680, MAX6695, MAX6696, and possibly
355 		 * others. Read register which is unsupported on MAX1617 but
356 		 * exists on all those chips and compare with the dev_id
357 		 * register. If it matches, it may be a MAX1617A.
358 		 */
359 		reg = i2c_smbus_read_byte_data(client,
360 					       ADM1023_REG_REM_TEMP_PREC);
361 		if (reg != dev_id)
362 			return -ENODEV;
363 		type_name = "max1617a";
364 	} else if (man_id == 0x41) {
365 		if ((dev_id & 0xF0) == 0x30)
366 			type_name = "adm1023";
367 		else if ((dev_id & 0xF0) == 0x00)
368 			type_name = "adm1021";
369 		else
370 			return -ENODEV;
371 	} else if (man_id == 0x49)
372 		type_name = "thmc10";
373 	else if (man_id == 0x23)
374 		type_name = "gl523sm";
375 	else if (man_id == 0x54)
376 		type_name = "mc1066";
377 	else {
378 		int lte, rte, lhi, rhi, llo, rlo;
379 
380 		/* extra checks for LM84 and MAX1617 to avoid misdetections */
381 
382 		llo = i2c_smbus_read_byte_data(client, ADM1021_REG_THYST_R(0));
383 		rlo = i2c_smbus_read_byte_data(client, ADM1021_REG_THYST_R(1));
384 
385 		/* fail if any of the additional register reads failed */
386 		if (llo < 0 || rlo < 0)
387 			return -ENODEV;
388 
389 		lte = i2c_smbus_read_byte_data(client, ADM1021_REG_TEMP(0));
390 		rte = i2c_smbus_read_byte_data(client, ADM1021_REG_TEMP(1));
391 		lhi = i2c_smbus_read_byte_data(client, ADM1021_REG_TOS_R(0));
392 		rhi = i2c_smbus_read_byte_data(client, ADM1021_REG_TOS_R(1));
393 
394 		/*
395 		 * Fail for negative temperatures and negative high limits.
396 		 * This check also catches read errors on the tested registers.
397 		 */
398 		if ((s8)lte < 0 || (s8)rte < 0 || (s8)lhi < 0 || (s8)rhi < 0)
399 			return -ENODEV;
400 
401 		/* fail if all registers hold the same value */
402 		if (lte == rte && lte == lhi && lte == rhi && lte == llo
403 		    && lte == rlo)
404 			return -ENODEV;
405 
406 		/*
407 		 * LM84 Mfr ID is in a different place,
408 		 * and it has more unused bits. Registers at 0xfe and 0xff
409 		 * are undefined and return the most recently read value,
410 		 * here the value of the configuration register.
411 		 */
412 		if (conv_rate == 0x00
413 		    && man_id == config && dev_id == config
414 		    && (config & 0x7F) == 0x00
415 		    && (status & 0xAB) == 0x00) {
416 			type_name = "lm84";
417 		} else {
418 			if ((config & 0x3f) || (status & 0x03))
419 				return -ENODEV;
420 			/* fail if low limits are larger than high limits */
421 			if ((s8)llo > lhi || (s8)rlo > rhi)
422 				return -ENODEV;
423 			type_name = "max1617";
424 		}
425 	}
426 
427 	pr_debug("Detected chip %s at adapter %d, address 0x%02x.\n",
428 		 type_name, i2c_adapter_id(adapter), client->addr);
429 	strscpy(info->type, type_name, I2C_NAME_SIZE);
430 
431 	return 0;
432 }
433 
434 static void adm1021_init_client(struct i2c_client *client)
435 {
436 	/* Enable ADC and disable suspend mode */
437 	i2c_smbus_write_byte_data(client, ADM1021_REG_CONFIG_W,
438 		i2c_smbus_read_byte_data(client, ADM1021_REG_CONFIG_R) & 0xBF);
439 	/* Set Conversion rate to 1/sec (this can be tinkered with) */
440 	i2c_smbus_write_byte_data(client, ADM1021_REG_CONV_RATE_W, 0x04);
441 }
442 
443 static const struct i2c_device_id adm1021_id[];
444 
445 static int adm1021_probe(struct i2c_client *client)
446 {
447 	struct device *dev = &client->dev;
448 	struct adm1021_data *data;
449 	struct device *hwmon_dev;
450 
451 	data = devm_kzalloc(dev, sizeof(struct adm1021_data), GFP_KERNEL);
452 	if (!data)
453 		return -ENOMEM;
454 
455 	data->client = client;
456 	data->type = i2c_match_id(adm1021_id, client)->driver_data;
457 	mutex_init(&data->update_lock);
458 
459 	/* Initialize the ADM1021 chip */
460 	if (data->type != lm84 && !read_only)
461 		adm1021_init_client(client);
462 
463 	data->groups[0] = &adm1021_group;
464 	if (data->type != lm84)
465 		data->groups[1] = &adm1021_min_group;
466 
467 	hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
468 							   data, data->groups);
469 
470 	return PTR_ERR_OR_ZERO(hwmon_dev);
471 }
472 
473 static const struct i2c_device_id adm1021_id[] = {
474 	{ "adm1021", adm1021 },
475 	{ "adm1023", adm1023 },
476 	{ "max1617", max1617 },
477 	{ "max1617a", max1617a },
478 	{ "thmc10", thmc10 },
479 	{ "lm84", lm84 },
480 	{ "gl523sm", gl523sm },
481 	{ "mc1066", mc1066 },
482 	{ }
483 };
484 MODULE_DEVICE_TABLE(i2c, adm1021_id);
485 
486 static struct i2c_driver adm1021_driver = {
487 	.class		= I2C_CLASS_HWMON,
488 	.driver = {
489 		.name	= "adm1021",
490 	},
491 	.probe_new	= adm1021_probe,
492 	.id_table	= adm1021_id,
493 	.detect		= adm1021_detect,
494 	.address_list	= normal_i2c,
495 };
496 
497 module_i2c_driver(adm1021_driver);
498 
499 MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl> and "
500 		"Philip Edelbrock <phil@netroedge.com>");
501 MODULE_DESCRIPTION("adm1021 driver");
502 MODULE_LICENSE("GPL");
503 
504 module_param(read_only, bool, 0);
505 MODULE_PARM_DESC(read_only, "Don't set any values, read only mode");
506