xref: /linux/drivers/hwmon/hwmon.c (revision d4ce5458ea1b7d8ca49c436d602095c4912777d3)
1 /*
2  * hwmon.c - part of lm_sensors, Linux kernel modules for hardware monitoring
3  *
4  * This file defines the sysfs class "hwmon", for use by sensors drivers.
5  *
6  * Copyright (C) 2005 Mark M. Hoffman <mhoffman@lightlink.com>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; version 2 of the License.
11  */
12 
13 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
14 
15 #include <linux/bitops.h>
16 #include <linux/device.h>
17 #include <linux/err.h>
18 #include <linux/gfp.h>
19 #include <linux/hwmon.h>
20 #include <linux/idr.h>
21 #include <linux/module.h>
22 #include <linux/pci.h>
23 #include <linux/slab.h>
24 #include <linux/string.h>
25 #include <linux/thermal.h>
26 
27 #define CREATE_TRACE_POINTS
28 #include <trace/events/hwmon.h>
29 
30 #define HWMON_ID_PREFIX "hwmon"
31 #define HWMON_ID_FORMAT HWMON_ID_PREFIX "%d"
32 
33 struct hwmon_device {
34 	const char *name;
35 	struct device dev;
36 	const struct hwmon_chip_info *chip;
37 
38 	struct attribute_group group;
39 	const struct attribute_group **groups;
40 };
41 
42 #define to_hwmon_device(d) container_of(d, struct hwmon_device, dev)
43 
44 #define MAX_SYSFS_ATTR_NAME_LENGTH	32
45 
46 struct hwmon_device_attribute {
47 	struct device_attribute dev_attr;
48 	const struct hwmon_ops *ops;
49 	enum hwmon_sensor_types type;
50 	u32 attr;
51 	int index;
52 	char name[MAX_SYSFS_ATTR_NAME_LENGTH];
53 };
54 
55 #define to_hwmon_attr(d) \
56 	container_of(d, struct hwmon_device_attribute, dev_attr)
57 
58 /*
59  * Thermal zone information
60  * In addition to the reference to the hwmon device,
61  * also provides the sensor index.
62  */
63 struct hwmon_thermal_data {
64 	struct hwmon_device *hwdev;	/* Reference to hwmon device */
65 	int index;			/* sensor index */
66 };
67 
68 static ssize_t
69 name_show(struct device *dev, struct device_attribute *attr, char *buf)
70 {
71 	return sprintf(buf, "%s\n", to_hwmon_device(dev)->name);
72 }
73 static DEVICE_ATTR_RO(name);
74 
75 static struct attribute *hwmon_dev_attrs[] = {
76 	&dev_attr_name.attr,
77 	NULL
78 };
79 
80 static umode_t hwmon_dev_name_is_visible(struct kobject *kobj,
81 					 struct attribute *attr, int n)
82 {
83 	struct device *dev = container_of(kobj, struct device, kobj);
84 
85 	if (to_hwmon_device(dev)->name == NULL)
86 		return 0;
87 
88 	return attr->mode;
89 }
90 
91 static const struct attribute_group hwmon_dev_attr_group = {
92 	.attrs		= hwmon_dev_attrs,
93 	.is_visible	= hwmon_dev_name_is_visible,
94 };
95 
96 static const struct attribute_group *hwmon_dev_attr_groups[] = {
97 	&hwmon_dev_attr_group,
98 	NULL
99 };
100 
101 static void hwmon_dev_release(struct device *dev)
102 {
103 	kfree(to_hwmon_device(dev));
104 }
105 
106 static struct class hwmon_class = {
107 	.name = "hwmon",
108 	.owner = THIS_MODULE,
109 	.dev_groups = hwmon_dev_attr_groups,
110 	.dev_release = hwmon_dev_release,
111 };
112 
113 static DEFINE_IDA(hwmon_ida);
114 
115 /* Thermal zone handling */
116 
117 /*
118  * The complex conditional is necessary to avoid a cyclic dependency
119  * between hwmon and thermal_sys modules.
120  */
121 #if IS_REACHABLE(CONFIG_THERMAL) && defined(CONFIG_THERMAL_OF) && \
122 	(!defined(CONFIG_THERMAL_HWMON) || \
123 	 !(defined(MODULE) && IS_MODULE(CONFIG_THERMAL)))
124 static int hwmon_thermal_get_temp(void *data, int *temp)
125 {
126 	struct hwmon_thermal_data *tdata = data;
127 	struct hwmon_device *hwdev = tdata->hwdev;
128 	int ret;
129 	long t;
130 
131 	ret = hwdev->chip->ops->read(&hwdev->dev, hwmon_temp, hwmon_temp_input,
132 				     tdata->index, &t);
133 	if (ret < 0)
134 		return ret;
135 
136 	*temp = t;
137 
138 	return 0;
139 }
140 
141 static const struct thermal_zone_of_device_ops hwmon_thermal_ops = {
142 	.get_temp = hwmon_thermal_get_temp,
143 };
144 
145 static int hwmon_thermal_add_sensor(struct device *dev,
146 				    struct hwmon_device *hwdev, int index)
147 {
148 	struct hwmon_thermal_data *tdata;
149 	struct thermal_zone_device *tzd;
150 
151 	tdata = devm_kzalloc(dev, sizeof(*tdata), GFP_KERNEL);
152 	if (!tdata)
153 		return -ENOMEM;
154 
155 	tdata->hwdev = hwdev;
156 	tdata->index = index;
157 
158 	tzd = devm_thermal_zone_of_sensor_register(&hwdev->dev, index, tdata,
159 						   &hwmon_thermal_ops);
160 	/*
161 	 * If CONFIG_THERMAL_OF is disabled, this returns -ENODEV,
162 	 * so ignore that error but forward any other error.
163 	 */
164 	if (IS_ERR(tzd) && (PTR_ERR(tzd) != -ENODEV))
165 		return PTR_ERR(tzd);
166 
167 	return 0;
168 }
169 #else
170 static int hwmon_thermal_add_sensor(struct device *dev,
171 				    struct hwmon_device *hwdev, int index)
172 {
173 	return 0;
174 }
175 #endif /* IS_REACHABLE(CONFIG_THERMAL) && ... */
176 
177 static int hwmon_attr_base(enum hwmon_sensor_types type)
178 {
179 	if (type == hwmon_in)
180 		return 0;
181 	return 1;
182 }
183 
184 /* sysfs attribute management */
185 
186 static ssize_t hwmon_attr_show(struct device *dev,
187 			       struct device_attribute *devattr, char *buf)
188 {
189 	struct hwmon_device_attribute *hattr = to_hwmon_attr(devattr);
190 	long val;
191 	int ret;
192 
193 	ret = hattr->ops->read(dev, hattr->type, hattr->attr, hattr->index,
194 			       &val);
195 	if (ret < 0)
196 		return ret;
197 
198 	trace_hwmon_attr_show(hattr->index + hwmon_attr_base(hattr->type),
199 			      hattr->name, val);
200 
201 	return sprintf(buf, "%ld\n", val);
202 }
203 
204 static ssize_t hwmon_attr_show_string(struct device *dev,
205 				      struct device_attribute *devattr,
206 				      char *buf)
207 {
208 	struct hwmon_device_attribute *hattr = to_hwmon_attr(devattr);
209 	enum hwmon_sensor_types type = hattr->type;
210 	const char *s;
211 	int ret;
212 
213 	ret = hattr->ops->read_string(dev, hattr->type, hattr->attr,
214 				      hattr->index, &s);
215 	if (ret < 0)
216 		return ret;
217 
218 	trace_hwmon_attr_show_string(hattr->index + hwmon_attr_base(type),
219 				     hattr->name, s);
220 
221 	return sprintf(buf, "%s\n", s);
222 }
223 
224 static ssize_t hwmon_attr_store(struct device *dev,
225 				struct device_attribute *devattr,
226 				const char *buf, size_t count)
227 {
228 	struct hwmon_device_attribute *hattr = to_hwmon_attr(devattr);
229 	long val;
230 	int ret;
231 
232 	ret = kstrtol(buf, 10, &val);
233 	if (ret < 0)
234 		return ret;
235 
236 	ret = hattr->ops->write(dev, hattr->type, hattr->attr, hattr->index,
237 				val);
238 	if (ret < 0)
239 		return ret;
240 
241 	trace_hwmon_attr_store(hattr->index + hwmon_attr_base(hattr->type),
242 			       hattr->name, val);
243 
244 	return count;
245 }
246 
247 static bool is_string_attr(enum hwmon_sensor_types type, u32 attr)
248 {
249 	return (type == hwmon_temp && attr == hwmon_temp_label) ||
250 	       (type == hwmon_in && attr == hwmon_in_label) ||
251 	       (type == hwmon_curr && attr == hwmon_curr_label) ||
252 	       (type == hwmon_power && attr == hwmon_power_label) ||
253 	       (type == hwmon_energy && attr == hwmon_energy_label) ||
254 	       (type == hwmon_humidity && attr == hwmon_humidity_label) ||
255 	       (type == hwmon_fan && attr == hwmon_fan_label);
256 }
257 
258 static struct attribute *hwmon_genattr(struct device *dev,
259 				       const void *drvdata,
260 				       enum hwmon_sensor_types type,
261 				       u32 attr,
262 				       int index,
263 				       const char *template,
264 				       const struct hwmon_ops *ops)
265 {
266 	struct hwmon_device_attribute *hattr;
267 	struct device_attribute *dattr;
268 	struct attribute *a;
269 	umode_t mode;
270 	const char *name;
271 	bool is_string = is_string_attr(type, attr);
272 
273 	/* The attribute is invisible if there is no template string */
274 	if (!template)
275 		return ERR_PTR(-ENOENT);
276 
277 	mode = ops->is_visible(drvdata, type, attr, index);
278 	if (!mode)
279 		return ERR_PTR(-ENOENT);
280 
281 	if ((mode & S_IRUGO) && ((is_string && !ops->read_string) ||
282 				 (!is_string && !ops->read)))
283 		return ERR_PTR(-EINVAL);
284 	if ((mode & S_IWUGO) && !ops->write)
285 		return ERR_PTR(-EINVAL);
286 
287 	hattr = devm_kzalloc(dev, sizeof(*hattr), GFP_KERNEL);
288 	if (!hattr)
289 		return ERR_PTR(-ENOMEM);
290 
291 	if (type == hwmon_chip) {
292 		name = template;
293 	} else {
294 		scnprintf(hattr->name, sizeof(hattr->name), template,
295 			  index + hwmon_attr_base(type));
296 		name = hattr->name;
297 	}
298 
299 	hattr->type = type;
300 	hattr->attr = attr;
301 	hattr->index = index;
302 	hattr->ops = ops;
303 
304 	dattr = &hattr->dev_attr;
305 	dattr->show = is_string ? hwmon_attr_show_string : hwmon_attr_show;
306 	dattr->store = hwmon_attr_store;
307 
308 	a = &dattr->attr;
309 	sysfs_attr_init(a);
310 	a->name = name;
311 	a->mode = mode;
312 
313 	return a;
314 }
315 
316 /*
317  * Chip attributes are not attribute templates but actual sysfs attributes.
318  * See hwmon_genattr() for special handling.
319  */
320 static const char * const hwmon_chip_attrs[] = {
321 	[hwmon_chip_temp_reset_history] = "temp_reset_history",
322 	[hwmon_chip_in_reset_history] = "in_reset_history",
323 	[hwmon_chip_curr_reset_history] = "curr_reset_history",
324 	[hwmon_chip_power_reset_history] = "power_reset_history",
325 	[hwmon_chip_update_interval] = "update_interval",
326 	[hwmon_chip_alarms] = "alarms",
327 };
328 
329 static const char * const hwmon_temp_attr_templates[] = {
330 	[hwmon_temp_input] = "temp%d_input",
331 	[hwmon_temp_type] = "temp%d_type",
332 	[hwmon_temp_lcrit] = "temp%d_lcrit",
333 	[hwmon_temp_lcrit_hyst] = "temp%d_lcrit_hyst",
334 	[hwmon_temp_min] = "temp%d_min",
335 	[hwmon_temp_min_hyst] = "temp%d_min_hyst",
336 	[hwmon_temp_max] = "temp%d_max",
337 	[hwmon_temp_max_hyst] = "temp%d_max_hyst",
338 	[hwmon_temp_crit] = "temp%d_crit",
339 	[hwmon_temp_crit_hyst] = "temp%d_crit_hyst",
340 	[hwmon_temp_emergency] = "temp%d_emergency",
341 	[hwmon_temp_emergency_hyst] = "temp%d_emergency_hyst",
342 	[hwmon_temp_alarm] = "temp%d_alarm",
343 	[hwmon_temp_lcrit_alarm] = "temp%d_lcrit_alarm",
344 	[hwmon_temp_min_alarm] = "temp%d_min_alarm",
345 	[hwmon_temp_max_alarm] = "temp%d_max_alarm",
346 	[hwmon_temp_crit_alarm] = "temp%d_crit_alarm",
347 	[hwmon_temp_emergency_alarm] = "temp%d_emergency_alarm",
348 	[hwmon_temp_fault] = "temp%d_fault",
349 	[hwmon_temp_offset] = "temp%d_offset",
350 	[hwmon_temp_label] = "temp%d_label",
351 	[hwmon_temp_lowest] = "temp%d_lowest",
352 	[hwmon_temp_highest] = "temp%d_highest",
353 	[hwmon_temp_reset_history] = "temp%d_reset_history",
354 };
355 
356 static const char * const hwmon_in_attr_templates[] = {
357 	[hwmon_in_input] = "in%d_input",
358 	[hwmon_in_min] = "in%d_min",
359 	[hwmon_in_max] = "in%d_max",
360 	[hwmon_in_lcrit] = "in%d_lcrit",
361 	[hwmon_in_crit] = "in%d_crit",
362 	[hwmon_in_average] = "in%d_average",
363 	[hwmon_in_lowest] = "in%d_lowest",
364 	[hwmon_in_highest] = "in%d_highest",
365 	[hwmon_in_reset_history] = "in%d_reset_history",
366 	[hwmon_in_label] = "in%d_label",
367 	[hwmon_in_alarm] = "in%d_alarm",
368 	[hwmon_in_min_alarm] = "in%d_min_alarm",
369 	[hwmon_in_max_alarm] = "in%d_max_alarm",
370 	[hwmon_in_lcrit_alarm] = "in%d_lcrit_alarm",
371 	[hwmon_in_crit_alarm] = "in%d_crit_alarm",
372 	[hwmon_in_enable] = "in%d_enable",
373 };
374 
375 static const char * const hwmon_curr_attr_templates[] = {
376 	[hwmon_curr_input] = "curr%d_input",
377 	[hwmon_curr_min] = "curr%d_min",
378 	[hwmon_curr_max] = "curr%d_max",
379 	[hwmon_curr_lcrit] = "curr%d_lcrit",
380 	[hwmon_curr_crit] = "curr%d_crit",
381 	[hwmon_curr_average] = "curr%d_average",
382 	[hwmon_curr_lowest] = "curr%d_lowest",
383 	[hwmon_curr_highest] = "curr%d_highest",
384 	[hwmon_curr_reset_history] = "curr%d_reset_history",
385 	[hwmon_curr_label] = "curr%d_label",
386 	[hwmon_curr_alarm] = "curr%d_alarm",
387 	[hwmon_curr_min_alarm] = "curr%d_min_alarm",
388 	[hwmon_curr_max_alarm] = "curr%d_max_alarm",
389 	[hwmon_curr_lcrit_alarm] = "curr%d_lcrit_alarm",
390 	[hwmon_curr_crit_alarm] = "curr%d_crit_alarm",
391 };
392 
393 static const char * const hwmon_power_attr_templates[] = {
394 	[hwmon_power_average] = "power%d_average",
395 	[hwmon_power_average_interval] = "power%d_average_interval",
396 	[hwmon_power_average_interval_max] = "power%d_interval_max",
397 	[hwmon_power_average_interval_min] = "power%d_interval_min",
398 	[hwmon_power_average_highest] = "power%d_average_highest",
399 	[hwmon_power_average_lowest] = "power%d_average_lowest",
400 	[hwmon_power_average_max] = "power%d_average_max",
401 	[hwmon_power_average_min] = "power%d_average_min",
402 	[hwmon_power_input] = "power%d_input",
403 	[hwmon_power_input_highest] = "power%d_input_highest",
404 	[hwmon_power_input_lowest] = "power%d_input_lowest",
405 	[hwmon_power_reset_history] = "power%d_reset_history",
406 	[hwmon_power_accuracy] = "power%d_accuracy",
407 	[hwmon_power_cap] = "power%d_cap",
408 	[hwmon_power_cap_hyst] = "power%d_cap_hyst",
409 	[hwmon_power_cap_max] = "power%d_cap_max",
410 	[hwmon_power_cap_min] = "power%d_cap_min",
411 	[hwmon_power_min] = "power%d_min",
412 	[hwmon_power_max] = "power%d_max",
413 	[hwmon_power_lcrit] = "power%d_lcrit",
414 	[hwmon_power_crit] = "power%d_crit",
415 	[hwmon_power_label] = "power%d_label",
416 	[hwmon_power_alarm] = "power%d_alarm",
417 	[hwmon_power_cap_alarm] = "power%d_cap_alarm",
418 	[hwmon_power_min_alarm] = "power%d_min_alarm",
419 	[hwmon_power_max_alarm] = "power%d_max_alarm",
420 	[hwmon_power_lcrit_alarm] = "power%d_lcrit_alarm",
421 	[hwmon_power_crit_alarm] = "power%d_crit_alarm",
422 };
423 
424 static const char * const hwmon_energy_attr_templates[] = {
425 	[hwmon_energy_input] = "energy%d_input",
426 	[hwmon_energy_label] = "energy%d_label",
427 };
428 
429 static const char * const hwmon_humidity_attr_templates[] = {
430 	[hwmon_humidity_input] = "humidity%d_input",
431 	[hwmon_humidity_label] = "humidity%d_label",
432 	[hwmon_humidity_min] = "humidity%d_min",
433 	[hwmon_humidity_min_hyst] = "humidity%d_min_hyst",
434 	[hwmon_humidity_max] = "humidity%d_max",
435 	[hwmon_humidity_max_hyst] = "humidity%d_max_hyst",
436 	[hwmon_humidity_alarm] = "humidity%d_alarm",
437 	[hwmon_humidity_fault] = "humidity%d_fault",
438 };
439 
440 static const char * const hwmon_fan_attr_templates[] = {
441 	[hwmon_fan_input] = "fan%d_input",
442 	[hwmon_fan_label] = "fan%d_label",
443 	[hwmon_fan_min] = "fan%d_min",
444 	[hwmon_fan_max] = "fan%d_max",
445 	[hwmon_fan_div] = "fan%d_div",
446 	[hwmon_fan_pulses] = "fan%d_pulses",
447 	[hwmon_fan_target] = "fan%d_target",
448 	[hwmon_fan_alarm] = "fan%d_alarm",
449 	[hwmon_fan_min_alarm] = "fan%d_min_alarm",
450 	[hwmon_fan_max_alarm] = "fan%d_max_alarm",
451 	[hwmon_fan_fault] = "fan%d_fault",
452 };
453 
454 static const char * const hwmon_pwm_attr_templates[] = {
455 	[hwmon_pwm_input] = "pwm%d",
456 	[hwmon_pwm_enable] = "pwm%d_enable",
457 	[hwmon_pwm_mode] = "pwm%d_mode",
458 	[hwmon_pwm_freq] = "pwm%d_freq",
459 };
460 
461 static const char * const *__templates[] = {
462 	[hwmon_chip] = hwmon_chip_attrs,
463 	[hwmon_temp] = hwmon_temp_attr_templates,
464 	[hwmon_in] = hwmon_in_attr_templates,
465 	[hwmon_curr] = hwmon_curr_attr_templates,
466 	[hwmon_power] = hwmon_power_attr_templates,
467 	[hwmon_energy] = hwmon_energy_attr_templates,
468 	[hwmon_humidity] = hwmon_humidity_attr_templates,
469 	[hwmon_fan] = hwmon_fan_attr_templates,
470 	[hwmon_pwm] = hwmon_pwm_attr_templates,
471 };
472 
473 static const int __templates_size[] = {
474 	[hwmon_chip] = ARRAY_SIZE(hwmon_chip_attrs),
475 	[hwmon_temp] = ARRAY_SIZE(hwmon_temp_attr_templates),
476 	[hwmon_in] = ARRAY_SIZE(hwmon_in_attr_templates),
477 	[hwmon_curr] = ARRAY_SIZE(hwmon_curr_attr_templates),
478 	[hwmon_power] = ARRAY_SIZE(hwmon_power_attr_templates),
479 	[hwmon_energy] = ARRAY_SIZE(hwmon_energy_attr_templates),
480 	[hwmon_humidity] = ARRAY_SIZE(hwmon_humidity_attr_templates),
481 	[hwmon_fan] = ARRAY_SIZE(hwmon_fan_attr_templates),
482 	[hwmon_pwm] = ARRAY_SIZE(hwmon_pwm_attr_templates),
483 };
484 
485 static int hwmon_num_channel_attrs(const struct hwmon_channel_info *info)
486 {
487 	int i, n;
488 
489 	for (i = n = 0; info->config[i]; i++)
490 		n += hweight32(info->config[i]);
491 
492 	return n;
493 }
494 
495 static int hwmon_genattrs(struct device *dev,
496 			  const void *drvdata,
497 			  struct attribute **attrs,
498 			  const struct hwmon_ops *ops,
499 			  const struct hwmon_channel_info *info)
500 {
501 	const char * const *templates;
502 	int template_size;
503 	int i, aindex = 0;
504 
505 	if (info->type >= ARRAY_SIZE(__templates))
506 		return -EINVAL;
507 
508 	templates = __templates[info->type];
509 	template_size = __templates_size[info->type];
510 
511 	for (i = 0; info->config[i]; i++) {
512 		u32 attr_mask = info->config[i];
513 		u32 attr;
514 
515 		while (attr_mask) {
516 			struct attribute *a;
517 
518 			attr = __ffs(attr_mask);
519 			attr_mask &= ~BIT(attr);
520 			if (attr >= template_size)
521 				return -EINVAL;
522 			a = hwmon_genattr(dev, drvdata, info->type, attr, i,
523 					  templates[attr], ops);
524 			if (IS_ERR(a)) {
525 				if (PTR_ERR(a) != -ENOENT)
526 					return PTR_ERR(a);
527 				continue;
528 			}
529 			attrs[aindex++] = a;
530 		}
531 	}
532 	return aindex;
533 }
534 
535 static struct attribute **
536 __hwmon_create_attrs(struct device *dev, const void *drvdata,
537 		     const struct hwmon_chip_info *chip)
538 {
539 	int ret, i, aindex = 0, nattrs = 0;
540 	struct attribute **attrs;
541 
542 	for (i = 0; chip->info[i]; i++)
543 		nattrs += hwmon_num_channel_attrs(chip->info[i]);
544 
545 	if (nattrs == 0)
546 		return ERR_PTR(-EINVAL);
547 
548 	attrs = devm_kcalloc(dev, nattrs + 1, sizeof(*attrs), GFP_KERNEL);
549 	if (!attrs)
550 		return ERR_PTR(-ENOMEM);
551 
552 	for (i = 0; chip->info[i]; i++) {
553 		ret = hwmon_genattrs(dev, drvdata, &attrs[aindex], chip->ops,
554 				     chip->info[i]);
555 		if (ret < 0)
556 			return ERR_PTR(ret);
557 		aindex += ret;
558 	}
559 
560 	return attrs;
561 }
562 
563 static struct device *
564 __hwmon_device_register(struct device *dev, const char *name, void *drvdata,
565 			const struct hwmon_chip_info *chip,
566 			const struct attribute_group **groups)
567 {
568 	struct hwmon_device *hwdev;
569 	struct device *hdev;
570 	int i, j, err, id;
571 
572 	/* Complain about invalid characters in hwmon name attribute */
573 	if (name && (!strlen(name) || strpbrk(name, "-* \t\n")))
574 		dev_warn(dev,
575 			 "hwmon: '%s' is not a valid name attribute, please fix\n",
576 			 name);
577 
578 	id = ida_simple_get(&hwmon_ida, 0, 0, GFP_KERNEL);
579 	if (id < 0)
580 		return ERR_PTR(id);
581 
582 	hwdev = kzalloc(sizeof(*hwdev), GFP_KERNEL);
583 	if (hwdev == NULL) {
584 		err = -ENOMEM;
585 		goto ida_remove;
586 	}
587 
588 	hdev = &hwdev->dev;
589 
590 	if (chip) {
591 		struct attribute **attrs;
592 		int ngroups = 2; /* terminating NULL plus &hwdev->groups */
593 
594 		if (groups)
595 			for (i = 0; groups[i]; i++)
596 				ngroups++;
597 
598 		hwdev->groups = devm_kcalloc(dev, ngroups, sizeof(*groups),
599 					     GFP_KERNEL);
600 		if (!hwdev->groups) {
601 			err = -ENOMEM;
602 			goto free_hwmon;
603 		}
604 
605 		attrs = __hwmon_create_attrs(dev, drvdata, chip);
606 		if (IS_ERR(attrs)) {
607 			err = PTR_ERR(attrs);
608 			goto free_hwmon;
609 		}
610 
611 		hwdev->group.attrs = attrs;
612 		ngroups = 0;
613 		hwdev->groups[ngroups++] = &hwdev->group;
614 
615 		if (groups) {
616 			for (i = 0; groups[i]; i++)
617 				hwdev->groups[ngroups++] = groups[i];
618 		}
619 
620 		hdev->groups = hwdev->groups;
621 	} else {
622 		hdev->groups = groups;
623 	}
624 
625 	hwdev->name = name;
626 	hdev->class = &hwmon_class;
627 	hdev->parent = dev;
628 	hdev->of_node = dev ? dev->of_node : NULL;
629 	hwdev->chip = chip;
630 	dev_set_drvdata(hdev, drvdata);
631 	dev_set_name(hdev, HWMON_ID_FORMAT, id);
632 	err = device_register(hdev);
633 	if (err)
634 		goto free_hwmon;
635 
636 	if (dev && chip && chip->ops->read &&
637 	    chip->info[0]->type == hwmon_chip &&
638 	    (chip->info[0]->config[0] & HWMON_C_REGISTER_TZ)) {
639 		const struct hwmon_channel_info **info = chip->info;
640 
641 		for (i = 1; info[i]; i++) {
642 			if (info[i]->type != hwmon_temp)
643 				continue;
644 
645 			for (j = 0; info[i]->config[j]; j++) {
646 				if (!chip->ops->is_visible(drvdata, hwmon_temp,
647 							   hwmon_temp_input, j))
648 					continue;
649 				if (info[i]->config[j] & HWMON_T_INPUT) {
650 					err = hwmon_thermal_add_sensor(dev,
651 								hwdev, j);
652 					if (err) {
653 						device_unregister(hdev);
654 						goto ida_remove;
655 					}
656 				}
657 			}
658 		}
659 	}
660 
661 	return hdev;
662 
663 free_hwmon:
664 	kfree(hwdev);
665 ida_remove:
666 	ida_simple_remove(&hwmon_ida, id);
667 	return ERR_PTR(err);
668 }
669 
670 /**
671  * hwmon_device_register_with_groups - register w/ hwmon
672  * @dev: the parent device
673  * @name: hwmon name attribute
674  * @drvdata: driver data to attach to created device
675  * @groups: List of attribute groups to create
676  *
677  * hwmon_device_unregister() must be called when the device is no
678  * longer needed.
679  *
680  * Returns the pointer to the new device.
681  */
682 struct device *
683 hwmon_device_register_with_groups(struct device *dev, const char *name,
684 				  void *drvdata,
685 				  const struct attribute_group **groups)
686 {
687 	if (!name)
688 		return ERR_PTR(-EINVAL);
689 
690 	return __hwmon_device_register(dev, name, drvdata, NULL, groups);
691 }
692 EXPORT_SYMBOL_GPL(hwmon_device_register_with_groups);
693 
694 /**
695  * hwmon_device_register_with_info - register w/ hwmon
696  * @dev: the parent device
697  * @name: hwmon name attribute
698  * @drvdata: driver data to attach to created device
699  * @chip: pointer to hwmon chip information
700  * @extra_groups: pointer to list of additional non-standard attribute groups
701  *
702  * hwmon_device_unregister() must be called when the device is no
703  * longer needed.
704  *
705  * Returns the pointer to the new device.
706  */
707 struct device *
708 hwmon_device_register_with_info(struct device *dev, const char *name,
709 				void *drvdata,
710 				const struct hwmon_chip_info *chip,
711 				const struct attribute_group **extra_groups)
712 {
713 	if (!name)
714 		return ERR_PTR(-EINVAL);
715 
716 	if (chip && (!chip->ops || !chip->ops->is_visible || !chip->info))
717 		return ERR_PTR(-EINVAL);
718 
719 	if (chip && !dev)
720 		return ERR_PTR(-EINVAL);
721 
722 	return __hwmon_device_register(dev, name, drvdata, chip, extra_groups);
723 }
724 EXPORT_SYMBOL_GPL(hwmon_device_register_with_info);
725 
726 /**
727  * hwmon_device_register - register w/ hwmon
728  * @dev: the device to register
729  *
730  * hwmon_device_unregister() must be called when the device is no
731  * longer needed.
732  *
733  * Returns the pointer to the new device.
734  */
735 struct device *hwmon_device_register(struct device *dev)
736 {
737 	dev_warn(dev,
738 		 "hwmon_device_register() is deprecated. Please convert the driver to use hwmon_device_register_with_info().\n");
739 
740 	return __hwmon_device_register(dev, NULL, NULL, NULL, NULL);
741 }
742 EXPORT_SYMBOL_GPL(hwmon_device_register);
743 
744 /**
745  * hwmon_device_unregister - removes the previously registered class device
746  *
747  * @dev: the class device to destroy
748  */
749 void hwmon_device_unregister(struct device *dev)
750 {
751 	int id;
752 
753 	if (likely(sscanf(dev_name(dev), HWMON_ID_FORMAT, &id) == 1)) {
754 		device_unregister(dev);
755 		ida_simple_remove(&hwmon_ida, id);
756 	} else
757 		dev_dbg(dev->parent,
758 			"hwmon_device_unregister() failed: bad class ID!\n");
759 }
760 EXPORT_SYMBOL_GPL(hwmon_device_unregister);
761 
762 static void devm_hwmon_release(struct device *dev, void *res)
763 {
764 	struct device *hwdev = *(struct device **)res;
765 
766 	hwmon_device_unregister(hwdev);
767 }
768 
769 /**
770  * devm_hwmon_device_register_with_groups - register w/ hwmon
771  * @dev: the parent device
772  * @name: hwmon name attribute
773  * @drvdata: driver data to attach to created device
774  * @groups: List of attribute groups to create
775  *
776  * Returns the pointer to the new device. The new device is automatically
777  * unregistered with the parent device.
778  */
779 struct device *
780 devm_hwmon_device_register_with_groups(struct device *dev, const char *name,
781 				       void *drvdata,
782 				       const struct attribute_group **groups)
783 {
784 	struct device **ptr, *hwdev;
785 
786 	if (!dev)
787 		return ERR_PTR(-EINVAL);
788 
789 	ptr = devres_alloc(devm_hwmon_release, sizeof(*ptr), GFP_KERNEL);
790 	if (!ptr)
791 		return ERR_PTR(-ENOMEM);
792 
793 	hwdev = hwmon_device_register_with_groups(dev, name, drvdata, groups);
794 	if (IS_ERR(hwdev))
795 		goto error;
796 
797 	*ptr = hwdev;
798 	devres_add(dev, ptr);
799 	return hwdev;
800 
801 error:
802 	devres_free(ptr);
803 	return hwdev;
804 }
805 EXPORT_SYMBOL_GPL(devm_hwmon_device_register_with_groups);
806 
807 /**
808  * devm_hwmon_device_register_with_info - register w/ hwmon
809  * @dev:	the parent device
810  * @name:	hwmon name attribute
811  * @drvdata:	driver data to attach to created device
812  * @chip:	pointer to hwmon chip information
813  * @groups:	pointer to list of driver specific attribute groups
814  *
815  * Returns the pointer to the new device. The new device is automatically
816  * unregistered with the parent device.
817  */
818 struct device *
819 devm_hwmon_device_register_with_info(struct device *dev, const char *name,
820 				     void *drvdata,
821 				     const struct hwmon_chip_info *chip,
822 				     const struct attribute_group **groups)
823 {
824 	struct device **ptr, *hwdev;
825 
826 	if (!dev)
827 		return ERR_PTR(-EINVAL);
828 
829 	ptr = devres_alloc(devm_hwmon_release, sizeof(*ptr), GFP_KERNEL);
830 	if (!ptr)
831 		return ERR_PTR(-ENOMEM);
832 
833 	hwdev = hwmon_device_register_with_info(dev, name, drvdata, chip,
834 						groups);
835 	if (IS_ERR(hwdev))
836 		goto error;
837 
838 	*ptr = hwdev;
839 	devres_add(dev, ptr);
840 
841 	return hwdev;
842 
843 error:
844 	devres_free(ptr);
845 	return hwdev;
846 }
847 EXPORT_SYMBOL_GPL(devm_hwmon_device_register_with_info);
848 
849 static int devm_hwmon_match(struct device *dev, void *res, void *data)
850 {
851 	struct device **hwdev = res;
852 
853 	return *hwdev == data;
854 }
855 
856 /**
857  * devm_hwmon_device_unregister - removes a previously registered hwmon device
858  *
859  * @dev: the parent device of the device to unregister
860  */
861 void devm_hwmon_device_unregister(struct device *dev)
862 {
863 	WARN_ON(devres_release(dev, devm_hwmon_release, devm_hwmon_match, dev));
864 }
865 EXPORT_SYMBOL_GPL(devm_hwmon_device_unregister);
866 
867 static void __init hwmon_pci_quirks(void)
868 {
869 #if defined CONFIG_X86 && defined CONFIG_PCI
870 	struct pci_dev *sb;
871 	u16 base;
872 	u8 enable;
873 
874 	/* Open access to 0x295-0x296 on MSI MS-7031 */
875 	sb = pci_get_device(PCI_VENDOR_ID_ATI, 0x436c, NULL);
876 	if (sb) {
877 		if (sb->subsystem_vendor == 0x1462 &&	/* MSI */
878 		    sb->subsystem_device == 0x0031) {	/* MS-7031 */
879 			pci_read_config_byte(sb, 0x48, &enable);
880 			pci_read_config_word(sb, 0x64, &base);
881 
882 			if (base == 0 && !(enable & BIT(2))) {
883 				dev_info(&sb->dev,
884 					 "Opening wide generic port at 0x295\n");
885 				pci_write_config_word(sb, 0x64, 0x295);
886 				pci_write_config_byte(sb, 0x48,
887 						      enable | BIT(2));
888 			}
889 		}
890 		pci_dev_put(sb);
891 	}
892 #endif
893 }
894 
895 static int __init hwmon_init(void)
896 {
897 	int err;
898 
899 	hwmon_pci_quirks();
900 
901 	err = class_register(&hwmon_class);
902 	if (err) {
903 		pr_err("couldn't register hwmon sysfs class\n");
904 		return err;
905 	}
906 	return 0;
907 }
908 
909 static void __exit hwmon_exit(void)
910 {
911 	class_unregister(&hwmon_class);
912 }
913 
914 subsys_initcall(hwmon_init);
915 module_exit(hwmon_exit);
916 
917 MODULE_AUTHOR("Mark M. Hoffman <mhoffman@lightlink.com>");
918 MODULE_DESCRIPTION("hardware monitoring sysfs/class support");
919 MODULE_LICENSE("GPL");
920 
921