xref: /openbmc/linux/drivers/hwmon/hwmon.c (revision a17922de)
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 HWMON_ID_PREFIX "hwmon"
28 #define HWMON_ID_FORMAT HWMON_ID_PREFIX "%d"
29 
30 struct hwmon_device {
31 	const char *name;
32 	struct device dev;
33 	const struct hwmon_chip_info *chip;
34 
35 	struct attribute_group group;
36 	const struct attribute_group **groups;
37 };
38 
39 #define to_hwmon_device(d) container_of(d, struct hwmon_device, dev)
40 
41 #define MAX_SYSFS_ATTR_NAME_LENGTH	32
42 
43 struct hwmon_device_attribute {
44 	struct device_attribute dev_attr;
45 	const struct hwmon_ops *ops;
46 	enum hwmon_sensor_types type;
47 	u32 attr;
48 	int index;
49 	char name[MAX_SYSFS_ATTR_NAME_LENGTH];
50 };
51 
52 #define to_hwmon_attr(d) \
53 	container_of(d, struct hwmon_device_attribute, dev_attr)
54 
55 /*
56  * Thermal zone information
57  * In addition to the reference to the hwmon device,
58  * also provides the sensor index.
59  */
60 struct hwmon_thermal_data {
61 	struct hwmon_device *hwdev;	/* Reference to hwmon device */
62 	int index;			/* sensor index */
63 };
64 
65 static ssize_t
66 name_show(struct device *dev, struct device_attribute *attr, char *buf)
67 {
68 	return sprintf(buf, "%s\n", to_hwmon_device(dev)->name);
69 }
70 static DEVICE_ATTR_RO(name);
71 
72 static struct attribute *hwmon_dev_attrs[] = {
73 	&dev_attr_name.attr,
74 	NULL
75 };
76 
77 static umode_t hwmon_dev_name_is_visible(struct kobject *kobj,
78 					 struct attribute *attr, int n)
79 {
80 	struct device *dev = container_of(kobj, struct device, kobj);
81 
82 	if (to_hwmon_device(dev)->name == NULL)
83 		return 0;
84 
85 	return attr->mode;
86 }
87 
88 static const struct attribute_group hwmon_dev_attr_group = {
89 	.attrs		= hwmon_dev_attrs,
90 	.is_visible	= hwmon_dev_name_is_visible,
91 };
92 
93 static const struct attribute_group *hwmon_dev_attr_groups[] = {
94 	&hwmon_dev_attr_group,
95 	NULL
96 };
97 
98 static void hwmon_dev_release(struct device *dev)
99 {
100 	kfree(to_hwmon_device(dev));
101 }
102 
103 static struct class hwmon_class = {
104 	.name = "hwmon",
105 	.owner = THIS_MODULE,
106 	.dev_groups = hwmon_dev_attr_groups,
107 	.dev_release = hwmon_dev_release,
108 };
109 
110 static DEFINE_IDA(hwmon_ida);
111 
112 /* Thermal zone handling */
113 
114 /*
115  * The complex conditional is necessary to avoid a cyclic dependency
116  * between hwmon and thermal_sys modules.
117  */
118 #if IS_REACHABLE(CONFIG_THERMAL) && defined(CONFIG_THERMAL_OF) && \
119 	(!defined(CONFIG_THERMAL_HWMON) || \
120 	 !(defined(MODULE) && IS_MODULE(CONFIG_THERMAL)))
121 static int hwmon_thermal_get_temp(void *data, int *temp)
122 {
123 	struct hwmon_thermal_data *tdata = data;
124 	struct hwmon_device *hwdev = tdata->hwdev;
125 	int ret;
126 	long t;
127 
128 	ret = hwdev->chip->ops->read(&hwdev->dev, hwmon_temp, hwmon_temp_input,
129 				     tdata->index, &t);
130 	if (ret < 0)
131 		return ret;
132 
133 	*temp = t;
134 
135 	return 0;
136 }
137 
138 static const struct thermal_zone_of_device_ops hwmon_thermal_ops = {
139 	.get_temp = hwmon_thermal_get_temp,
140 };
141 
142 static int hwmon_thermal_add_sensor(struct device *dev,
143 				    struct hwmon_device *hwdev, int index)
144 {
145 	struct hwmon_thermal_data *tdata;
146 	struct thermal_zone_device *tzd;
147 
148 	tdata = devm_kzalloc(dev, sizeof(*tdata), GFP_KERNEL);
149 	if (!tdata)
150 		return -ENOMEM;
151 
152 	tdata->hwdev = hwdev;
153 	tdata->index = index;
154 
155 	tzd = devm_thermal_zone_of_sensor_register(&hwdev->dev, index, tdata,
156 						   &hwmon_thermal_ops);
157 	/*
158 	 * If CONFIG_THERMAL_OF is disabled, this returns -ENODEV,
159 	 * so ignore that error but forward any other error.
160 	 */
161 	if (IS_ERR(tzd) && (PTR_ERR(tzd) != -ENODEV))
162 		return PTR_ERR(tzd);
163 
164 	return 0;
165 }
166 #else
167 static int hwmon_thermal_add_sensor(struct device *dev,
168 				    struct hwmon_device *hwdev, int index)
169 {
170 	return 0;
171 }
172 #endif /* IS_REACHABLE(CONFIG_THERMAL) && ... */
173 
174 /* sysfs attribute management */
175 
176 static ssize_t hwmon_attr_show(struct device *dev,
177 			       struct device_attribute *devattr, char *buf)
178 {
179 	struct hwmon_device_attribute *hattr = to_hwmon_attr(devattr);
180 	long val;
181 	int ret;
182 
183 	ret = hattr->ops->read(dev, hattr->type, hattr->attr, hattr->index,
184 			       &val);
185 	if (ret < 0)
186 		return ret;
187 
188 	return sprintf(buf, "%ld\n", val);
189 }
190 
191 static ssize_t hwmon_attr_show_string(struct device *dev,
192 				      struct device_attribute *devattr,
193 				      char *buf)
194 {
195 	struct hwmon_device_attribute *hattr = to_hwmon_attr(devattr);
196 	const char *s;
197 	int ret;
198 
199 	ret = hattr->ops->read_string(dev, hattr->type, hattr->attr,
200 				      hattr->index, &s);
201 	if (ret < 0)
202 		return ret;
203 
204 	return sprintf(buf, "%s\n", s);
205 }
206 
207 static ssize_t hwmon_attr_store(struct device *dev,
208 				struct device_attribute *devattr,
209 				const char *buf, size_t count)
210 {
211 	struct hwmon_device_attribute *hattr = to_hwmon_attr(devattr);
212 	long val;
213 	int ret;
214 
215 	ret = kstrtol(buf, 10, &val);
216 	if (ret < 0)
217 		return ret;
218 
219 	ret = hattr->ops->write(dev, hattr->type, hattr->attr, hattr->index,
220 				val);
221 	if (ret < 0)
222 		return ret;
223 
224 	return count;
225 }
226 
227 static int hwmon_attr_base(enum hwmon_sensor_types type)
228 {
229 	if (type == hwmon_in)
230 		return 0;
231 	return 1;
232 }
233 
234 static bool is_string_attr(enum hwmon_sensor_types type, u32 attr)
235 {
236 	return (type == hwmon_temp && attr == hwmon_temp_label) ||
237 	       (type == hwmon_in && attr == hwmon_in_label) ||
238 	       (type == hwmon_curr && attr == hwmon_curr_label) ||
239 	       (type == hwmon_power && attr == hwmon_power_label) ||
240 	       (type == hwmon_energy && attr == hwmon_energy_label) ||
241 	       (type == hwmon_humidity && attr == hwmon_humidity_label) ||
242 	       (type == hwmon_fan && attr == hwmon_fan_label);
243 }
244 
245 static struct attribute *hwmon_genattr(struct device *dev,
246 				       const void *drvdata,
247 				       enum hwmon_sensor_types type,
248 				       u32 attr,
249 				       int index,
250 				       const char *template,
251 				       const struct hwmon_ops *ops)
252 {
253 	struct hwmon_device_attribute *hattr;
254 	struct device_attribute *dattr;
255 	struct attribute *a;
256 	umode_t mode;
257 	char *name;
258 	bool is_string = is_string_attr(type, attr);
259 
260 	/* The attribute is invisible if there is no template string */
261 	if (!template)
262 		return ERR_PTR(-ENOENT);
263 
264 	mode = ops->is_visible(drvdata, type, attr, index);
265 	if (!mode)
266 		return ERR_PTR(-ENOENT);
267 
268 	if ((mode & S_IRUGO) && ((is_string && !ops->read_string) ||
269 				 (!is_string && !ops->read)))
270 		return ERR_PTR(-EINVAL);
271 	if ((mode & S_IWUGO) && !ops->write)
272 		return ERR_PTR(-EINVAL);
273 
274 	hattr = devm_kzalloc(dev, sizeof(*hattr), GFP_KERNEL);
275 	if (!hattr)
276 		return ERR_PTR(-ENOMEM);
277 
278 	if (type == hwmon_chip) {
279 		name = (char *)template;
280 	} else {
281 		scnprintf(hattr->name, sizeof(hattr->name), template,
282 			  index + hwmon_attr_base(type));
283 		name = hattr->name;
284 	}
285 
286 	hattr->type = type;
287 	hattr->attr = attr;
288 	hattr->index = index;
289 	hattr->ops = ops;
290 
291 	dattr = &hattr->dev_attr;
292 	dattr->show = is_string ? hwmon_attr_show_string : hwmon_attr_show;
293 	dattr->store = hwmon_attr_store;
294 
295 	a = &dattr->attr;
296 	sysfs_attr_init(a);
297 	a->name = name;
298 	a->mode = mode;
299 
300 	return a;
301 }
302 
303 /*
304  * Chip attributes are not attribute templates but actual sysfs attributes.
305  * See hwmon_genattr() for special handling.
306  */
307 static const char * const hwmon_chip_attrs[] = {
308 	[hwmon_chip_temp_reset_history] = "temp_reset_history",
309 	[hwmon_chip_in_reset_history] = "in_reset_history",
310 	[hwmon_chip_curr_reset_history] = "curr_reset_history",
311 	[hwmon_chip_power_reset_history] = "power_reset_history",
312 	[hwmon_chip_update_interval] = "update_interval",
313 	[hwmon_chip_alarms] = "alarms",
314 };
315 
316 static const char * const hwmon_temp_attr_templates[] = {
317 	[hwmon_temp_input] = "temp%d_input",
318 	[hwmon_temp_type] = "temp%d_type",
319 	[hwmon_temp_lcrit] = "temp%d_lcrit",
320 	[hwmon_temp_lcrit_hyst] = "temp%d_lcrit_hyst",
321 	[hwmon_temp_min] = "temp%d_min",
322 	[hwmon_temp_min_hyst] = "temp%d_min_hyst",
323 	[hwmon_temp_max] = "temp%d_max",
324 	[hwmon_temp_max_hyst] = "temp%d_max_hyst",
325 	[hwmon_temp_crit] = "temp%d_crit",
326 	[hwmon_temp_crit_hyst] = "temp%d_crit_hyst",
327 	[hwmon_temp_emergency] = "temp%d_emergency",
328 	[hwmon_temp_emergency_hyst] = "temp%d_emergency_hyst",
329 	[hwmon_temp_alarm] = "temp%d_alarm",
330 	[hwmon_temp_lcrit_alarm] = "temp%d_lcrit_alarm",
331 	[hwmon_temp_min_alarm] = "temp%d_min_alarm",
332 	[hwmon_temp_max_alarm] = "temp%d_max_alarm",
333 	[hwmon_temp_crit_alarm] = "temp%d_crit_alarm",
334 	[hwmon_temp_emergency_alarm] = "temp%d_emergency_alarm",
335 	[hwmon_temp_fault] = "temp%d_fault",
336 	[hwmon_temp_offset] = "temp%d_offset",
337 	[hwmon_temp_label] = "temp%d_label",
338 	[hwmon_temp_lowest] = "temp%d_lowest",
339 	[hwmon_temp_highest] = "temp%d_highest",
340 	[hwmon_temp_reset_history] = "temp%d_reset_history",
341 };
342 
343 static const char * const hwmon_in_attr_templates[] = {
344 	[hwmon_in_input] = "in%d_input",
345 	[hwmon_in_min] = "in%d_min",
346 	[hwmon_in_max] = "in%d_max",
347 	[hwmon_in_lcrit] = "in%d_lcrit",
348 	[hwmon_in_crit] = "in%d_crit",
349 	[hwmon_in_average] = "in%d_average",
350 	[hwmon_in_lowest] = "in%d_lowest",
351 	[hwmon_in_highest] = "in%d_highest",
352 	[hwmon_in_reset_history] = "in%d_reset_history",
353 	[hwmon_in_label] = "in%d_label",
354 	[hwmon_in_alarm] = "in%d_alarm",
355 	[hwmon_in_min_alarm] = "in%d_min_alarm",
356 	[hwmon_in_max_alarm] = "in%d_max_alarm",
357 	[hwmon_in_lcrit_alarm] = "in%d_lcrit_alarm",
358 	[hwmon_in_crit_alarm] = "in%d_crit_alarm",
359 };
360 
361 static const char * const hwmon_curr_attr_templates[] = {
362 	[hwmon_curr_input] = "curr%d_input",
363 	[hwmon_curr_min] = "curr%d_min",
364 	[hwmon_curr_max] = "curr%d_max",
365 	[hwmon_curr_lcrit] = "curr%d_lcrit",
366 	[hwmon_curr_crit] = "curr%d_crit",
367 	[hwmon_curr_average] = "curr%d_average",
368 	[hwmon_curr_lowest] = "curr%d_lowest",
369 	[hwmon_curr_highest] = "curr%d_highest",
370 	[hwmon_curr_reset_history] = "curr%d_reset_history",
371 	[hwmon_curr_label] = "curr%d_label",
372 	[hwmon_curr_alarm] = "curr%d_alarm",
373 	[hwmon_curr_min_alarm] = "curr%d_min_alarm",
374 	[hwmon_curr_max_alarm] = "curr%d_max_alarm",
375 	[hwmon_curr_lcrit_alarm] = "curr%d_lcrit_alarm",
376 	[hwmon_curr_crit_alarm] = "curr%d_crit_alarm",
377 };
378 
379 static const char * const hwmon_power_attr_templates[] = {
380 	[hwmon_power_average] = "power%d_average",
381 	[hwmon_power_average_interval] = "power%d_average_interval",
382 	[hwmon_power_average_interval_max] = "power%d_interval_max",
383 	[hwmon_power_average_interval_min] = "power%d_interval_min",
384 	[hwmon_power_average_highest] = "power%d_average_highest",
385 	[hwmon_power_average_lowest] = "power%d_average_lowest",
386 	[hwmon_power_average_max] = "power%d_average_max",
387 	[hwmon_power_average_min] = "power%d_average_min",
388 	[hwmon_power_input] = "power%d_input",
389 	[hwmon_power_input_highest] = "power%d_input_highest",
390 	[hwmon_power_input_lowest] = "power%d_input_lowest",
391 	[hwmon_power_reset_history] = "power%d_reset_history",
392 	[hwmon_power_accuracy] = "power%d_accuracy",
393 	[hwmon_power_cap] = "power%d_cap",
394 	[hwmon_power_cap_hyst] = "power%d_cap_hyst",
395 	[hwmon_power_cap_max] = "power%d_cap_max",
396 	[hwmon_power_cap_min] = "power%d_cap_min",
397 	[hwmon_power_min] = "power%d_min",
398 	[hwmon_power_max] = "power%d_max",
399 	[hwmon_power_lcrit] = "power%d_lcrit",
400 	[hwmon_power_crit] = "power%d_crit",
401 	[hwmon_power_label] = "power%d_label",
402 	[hwmon_power_alarm] = "power%d_alarm",
403 	[hwmon_power_cap_alarm] = "power%d_cap_alarm",
404 	[hwmon_power_min_alarm] = "power%d_min_alarm",
405 	[hwmon_power_max_alarm] = "power%d_max_alarm",
406 	[hwmon_power_lcrit_alarm] = "power%d_lcrit_alarm",
407 	[hwmon_power_crit_alarm] = "power%d_crit_alarm",
408 };
409 
410 static const char * const hwmon_energy_attr_templates[] = {
411 	[hwmon_energy_input] = "energy%d_input",
412 	[hwmon_energy_label] = "energy%d_label",
413 };
414 
415 static const char * const hwmon_humidity_attr_templates[] = {
416 	[hwmon_humidity_input] = "humidity%d_input",
417 	[hwmon_humidity_label] = "humidity%d_label",
418 	[hwmon_humidity_min] = "humidity%d_min",
419 	[hwmon_humidity_min_hyst] = "humidity%d_min_hyst",
420 	[hwmon_humidity_max] = "humidity%d_max",
421 	[hwmon_humidity_max_hyst] = "humidity%d_max_hyst",
422 	[hwmon_humidity_alarm] = "humidity%d_alarm",
423 	[hwmon_humidity_fault] = "humidity%d_fault",
424 };
425 
426 static const char * const hwmon_fan_attr_templates[] = {
427 	[hwmon_fan_input] = "fan%d_input",
428 	[hwmon_fan_label] = "fan%d_label",
429 	[hwmon_fan_min] = "fan%d_min",
430 	[hwmon_fan_max] = "fan%d_max",
431 	[hwmon_fan_div] = "fan%d_div",
432 	[hwmon_fan_pulses] = "fan%d_pulses",
433 	[hwmon_fan_target] = "fan%d_target",
434 	[hwmon_fan_alarm] = "fan%d_alarm",
435 	[hwmon_fan_min_alarm] = "fan%d_min_alarm",
436 	[hwmon_fan_max_alarm] = "fan%d_max_alarm",
437 	[hwmon_fan_fault] = "fan%d_fault",
438 };
439 
440 static const char * const hwmon_pwm_attr_templates[] = {
441 	[hwmon_pwm_input] = "pwm%d",
442 	[hwmon_pwm_enable] = "pwm%d_enable",
443 	[hwmon_pwm_mode] = "pwm%d_mode",
444 	[hwmon_pwm_freq] = "pwm%d_freq",
445 };
446 
447 static const char * const *__templates[] = {
448 	[hwmon_chip] = hwmon_chip_attrs,
449 	[hwmon_temp] = hwmon_temp_attr_templates,
450 	[hwmon_in] = hwmon_in_attr_templates,
451 	[hwmon_curr] = hwmon_curr_attr_templates,
452 	[hwmon_power] = hwmon_power_attr_templates,
453 	[hwmon_energy] = hwmon_energy_attr_templates,
454 	[hwmon_humidity] = hwmon_humidity_attr_templates,
455 	[hwmon_fan] = hwmon_fan_attr_templates,
456 	[hwmon_pwm] = hwmon_pwm_attr_templates,
457 };
458 
459 static const int __templates_size[] = {
460 	[hwmon_chip] = ARRAY_SIZE(hwmon_chip_attrs),
461 	[hwmon_temp] = ARRAY_SIZE(hwmon_temp_attr_templates),
462 	[hwmon_in] = ARRAY_SIZE(hwmon_in_attr_templates),
463 	[hwmon_curr] = ARRAY_SIZE(hwmon_curr_attr_templates),
464 	[hwmon_power] = ARRAY_SIZE(hwmon_power_attr_templates),
465 	[hwmon_energy] = ARRAY_SIZE(hwmon_energy_attr_templates),
466 	[hwmon_humidity] = ARRAY_SIZE(hwmon_humidity_attr_templates),
467 	[hwmon_fan] = ARRAY_SIZE(hwmon_fan_attr_templates),
468 	[hwmon_pwm] = ARRAY_SIZE(hwmon_pwm_attr_templates),
469 };
470 
471 static int hwmon_num_channel_attrs(const struct hwmon_channel_info *info)
472 {
473 	int i, n;
474 
475 	for (i = n = 0; info->config[i]; i++)
476 		n += hweight32(info->config[i]);
477 
478 	return n;
479 }
480 
481 static int hwmon_genattrs(struct device *dev,
482 			  const void *drvdata,
483 			  struct attribute **attrs,
484 			  const struct hwmon_ops *ops,
485 			  const struct hwmon_channel_info *info)
486 {
487 	const char * const *templates;
488 	int template_size;
489 	int i, aindex = 0;
490 
491 	if (info->type >= ARRAY_SIZE(__templates))
492 		return -EINVAL;
493 
494 	templates = __templates[info->type];
495 	template_size = __templates_size[info->type];
496 
497 	for (i = 0; info->config[i]; i++) {
498 		u32 attr_mask = info->config[i];
499 		u32 attr;
500 
501 		while (attr_mask) {
502 			struct attribute *a;
503 
504 			attr = __ffs(attr_mask);
505 			attr_mask &= ~BIT(attr);
506 			if (attr >= template_size)
507 				return -EINVAL;
508 			a = hwmon_genattr(dev, drvdata, info->type, attr, i,
509 					  templates[attr], ops);
510 			if (IS_ERR(a)) {
511 				if (PTR_ERR(a) != -ENOENT)
512 					return PTR_ERR(a);
513 				continue;
514 			}
515 			attrs[aindex++] = a;
516 		}
517 	}
518 	return aindex;
519 }
520 
521 static struct attribute **
522 __hwmon_create_attrs(struct device *dev, const void *drvdata,
523 		     const struct hwmon_chip_info *chip)
524 {
525 	int ret, i, aindex = 0, nattrs = 0;
526 	struct attribute **attrs;
527 
528 	for (i = 0; chip->info[i]; i++)
529 		nattrs += hwmon_num_channel_attrs(chip->info[i]);
530 
531 	if (nattrs == 0)
532 		return ERR_PTR(-EINVAL);
533 
534 	attrs = devm_kcalloc(dev, nattrs + 1, sizeof(*attrs), GFP_KERNEL);
535 	if (!attrs)
536 		return ERR_PTR(-ENOMEM);
537 
538 	for (i = 0; chip->info[i]; i++) {
539 		ret = hwmon_genattrs(dev, drvdata, &attrs[aindex], chip->ops,
540 				     chip->info[i]);
541 		if (ret < 0)
542 			return ERR_PTR(ret);
543 		aindex += ret;
544 	}
545 
546 	return attrs;
547 }
548 
549 static struct device *
550 __hwmon_device_register(struct device *dev, const char *name, void *drvdata,
551 			const struct hwmon_chip_info *chip,
552 			const struct attribute_group **groups)
553 {
554 	struct hwmon_device *hwdev;
555 	struct device *hdev;
556 	int i, j, err, id;
557 
558 	/* Complain about invalid characters in hwmon name attribute */
559 	if (name && (!strlen(name) || strpbrk(name, "-* \t\n")))
560 		dev_warn(dev,
561 			 "hwmon: '%s' is not a valid name attribute, please fix\n",
562 			 name);
563 
564 	id = ida_simple_get(&hwmon_ida, 0, 0, GFP_KERNEL);
565 	if (id < 0)
566 		return ERR_PTR(id);
567 
568 	hwdev = kzalloc(sizeof(*hwdev), GFP_KERNEL);
569 	if (hwdev == NULL) {
570 		err = -ENOMEM;
571 		goto ida_remove;
572 	}
573 
574 	hdev = &hwdev->dev;
575 
576 	if (chip) {
577 		struct attribute **attrs;
578 		int ngroups = 2; /* terminating NULL plus &hwdev->groups */
579 
580 		if (groups)
581 			for (i = 0; groups[i]; i++)
582 				ngroups++;
583 
584 		hwdev->groups = devm_kcalloc(dev, ngroups, sizeof(*groups),
585 					     GFP_KERNEL);
586 		if (!hwdev->groups) {
587 			err = -ENOMEM;
588 			goto free_hwmon;
589 		}
590 
591 		attrs = __hwmon_create_attrs(dev, drvdata, chip);
592 		if (IS_ERR(attrs)) {
593 			err = PTR_ERR(attrs);
594 			goto free_hwmon;
595 		}
596 
597 		hwdev->group.attrs = attrs;
598 		ngroups = 0;
599 		hwdev->groups[ngroups++] = &hwdev->group;
600 
601 		if (groups) {
602 			for (i = 0; groups[i]; i++)
603 				hwdev->groups[ngroups++] = groups[i];
604 		}
605 
606 		hdev->groups = hwdev->groups;
607 	} else {
608 		hdev->groups = groups;
609 	}
610 
611 	hwdev->name = name;
612 	hdev->class = &hwmon_class;
613 	hdev->parent = dev;
614 	hdev->of_node = dev ? dev->of_node : NULL;
615 	hwdev->chip = chip;
616 	dev_set_drvdata(hdev, drvdata);
617 	dev_set_name(hdev, HWMON_ID_FORMAT, id);
618 	err = device_register(hdev);
619 	if (err)
620 		goto free_hwmon;
621 
622 	if (dev && chip && chip->ops->read &&
623 	    chip->info[0]->type == hwmon_chip &&
624 	    (chip->info[0]->config[0] & HWMON_C_REGISTER_TZ)) {
625 		const struct hwmon_channel_info **info = chip->info;
626 
627 		for (i = 1; info[i]; i++) {
628 			if (info[i]->type != hwmon_temp)
629 				continue;
630 
631 			for (j = 0; info[i]->config[j]; j++) {
632 				if (!chip->ops->is_visible(drvdata, hwmon_temp,
633 							   hwmon_temp_input, j))
634 					continue;
635 				if (info[i]->config[j] & HWMON_T_INPUT) {
636 					err = hwmon_thermal_add_sensor(dev,
637 								hwdev, j);
638 					if (err)
639 						goto free_device;
640 				}
641 			}
642 		}
643 	}
644 
645 	return hdev;
646 
647 free_device:
648 	device_unregister(hdev);
649 free_hwmon:
650 	kfree(hwdev);
651 ida_remove:
652 	ida_simple_remove(&hwmon_ida, id);
653 	return ERR_PTR(err);
654 }
655 
656 /**
657  * hwmon_device_register_with_groups - register w/ hwmon
658  * @dev: the parent device
659  * @name: hwmon name attribute
660  * @drvdata: driver data to attach to created device
661  * @groups: List of attribute groups to create
662  *
663  * hwmon_device_unregister() must be called when the device is no
664  * longer needed.
665  *
666  * Returns the pointer to the new device.
667  */
668 struct device *
669 hwmon_device_register_with_groups(struct device *dev, const char *name,
670 				  void *drvdata,
671 				  const struct attribute_group **groups)
672 {
673 	if (!name)
674 		return ERR_PTR(-EINVAL);
675 
676 	return __hwmon_device_register(dev, name, drvdata, NULL, groups);
677 }
678 EXPORT_SYMBOL_GPL(hwmon_device_register_with_groups);
679 
680 /**
681  * hwmon_device_register_with_info - register w/ hwmon
682  * @dev: the parent device
683  * @name: hwmon name attribute
684  * @drvdata: driver data to attach to created device
685  * @chip: pointer to hwmon chip information
686  * @extra_groups: pointer to list of additional non-standard attribute groups
687  *
688  * hwmon_device_unregister() must be called when the device is no
689  * longer needed.
690  *
691  * Returns the pointer to the new device.
692  */
693 struct device *
694 hwmon_device_register_with_info(struct device *dev, const char *name,
695 				void *drvdata,
696 				const struct hwmon_chip_info *chip,
697 				const struct attribute_group **extra_groups)
698 {
699 	if (!name)
700 		return ERR_PTR(-EINVAL);
701 
702 	if (chip && (!chip->ops || !chip->ops->is_visible || !chip->info))
703 		return ERR_PTR(-EINVAL);
704 
705 	if (chip && !dev)
706 		return ERR_PTR(-EINVAL);
707 
708 	return __hwmon_device_register(dev, name, drvdata, chip, extra_groups);
709 }
710 EXPORT_SYMBOL_GPL(hwmon_device_register_with_info);
711 
712 /**
713  * hwmon_device_register - register w/ hwmon
714  * @dev: the device to register
715  *
716  * hwmon_device_unregister() must be called when the device is no
717  * longer needed.
718  *
719  * Returns the pointer to the new device.
720  */
721 struct device *hwmon_device_register(struct device *dev)
722 {
723 	dev_warn(dev,
724 		 "hwmon_device_register() is deprecated. Please convert the driver to use hwmon_device_register_with_info().\n");
725 
726 	return __hwmon_device_register(dev, NULL, NULL, NULL, NULL);
727 }
728 EXPORT_SYMBOL_GPL(hwmon_device_register);
729 
730 /**
731  * hwmon_device_unregister - removes the previously registered class device
732  *
733  * @dev: the class device to destroy
734  */
735 void hwmon_device_unregister(struct device *dev)
736 {
737 	int id;
738 
739 	if (likely(sscanf(dev_name(dev), HWMON_ID_FORMAT, &id) == 1)) {
740 		device_unregister(dev);
741 		ida_simple_remove(&hwmon_ida, id);
742 	} else
743 		dev_dbg(dev->parent,
744 			"hwmon_device_unregister() failed: bad class ID!\n");
745 }
746 EXPORT_SYMBOL_GPL(hwmon_device_unregister);
747 
748 static void devm_hwmon_release(struct device *dev, void *res)
749 {
750 	struct device *hwdev = *(struct device **)res;
751 
752 	hwmon_device_unregister(hwdev);
753 }
754 
755 /**
756  * devm_hwmon_device_register_with_groups - register w/ hwmon
757  * @dev: the parent device
758  * @name: hwmon name attribute
759  * @drvdata: driver data to attach to created device
760  * @groups: List of attribute groups to create
761  *
762  * Returns the pointer to the new device. The new device is automatically
763  * unregistered with the parent device.
764  */
765 struct device *
766 devm_hwmon_device_register_with_groups(struct device *dev, const char *name,
767 				       void *drvdata,
768 				       const struct attribute_group **groups)
769 {
770 	struct device **ptr, *hwdev;
771 
772 	if (!dev)
773 		return ERR_PTR(-EINVAL);
774 
775 	ptr = devres_alloc(devm_hwmon_release, sizeof(*ptr), GFP_KERNEL);
776 	if (!ptr)
777 		return ERR_PTR(-ENOMEM);
778 
779 	hwdev = hwmon_device_register_with_groups(dev, name, drvdata, groups);
780 	if (IS_ERR(hwdev))
781 		goto error;
782 
783 	*ptr = hwdev;
784 	devres_add(dev, ptr);
785 	return hwdev;
786 
787 error:
788 	devres_free(ptr);
789 	return hwdev;
790 }
791 EXPORT_SYMBOL_GPL(devm_hwmon_device_register_with_groups);
792 
793 /**
794  * devm_hwmon_device_register_with_info - register w/ hwmon
795  * @dev:	the parent device
796  * @name:	hwmon name attribute
797  * @drvdata:	driver data to attach to created device
798  * @chip:	pointer to hwmon chip information
799  * @groups:	pointer to list of driver specific attribute groups
800  *
801  * Returns the pointer to the new device. The new device is automatically
802  * unregistered with the parent device.
803  */
804 struct device *
805 devm_hwmon_device_register_with_info(struct device *dev, const char *name,
806 				     void *drvdata,
807 				     const struct hwmon_chip_info *chip,
808 				     const struct attribute_group **groups)
809 {
810 	struct device **ptr, *hwdev;
811 
812 	if (!dev)
813 		return ERR_PTR(-EINVAL);
814 
815 	ptr = devres_alloc(devm_hwmon_release, sizeof(*ptr), GFP_KERNEL);
816 	if (!ptr)
817 		return ERR_PTR(-ENOMEM);
818 
819 	hwdev = hwmon_device_register_with_info(dev, name, drvdata, chip,
820 						groups);
821 	if (IS_ERR(hwdev))
822 		goto error;
823 
824 	*ptr = hwdev;
825 	devres_add(dev, ptr);
826 
827 	return hwdev;
828 
829 error:
830 	devres_free(ptr);
831 	return hwdev;
832 }
833 EXPORT_SYMBOL_GPL(devm_hwmon_device_register_with_info);
834 
835 static int devm_hwmon_match(struct device *dev, void *res, void *data)
836 {
837 	struct device **hwdev = res;
838 
839 	return *hwdev == data;
840 }
841 
842 /**
843  * devm_hwmon_device_unregister - removes a previously registered hwmon device
844  *
845  * @dev: the parent device of the device to unregister
846  */
847 void devm_hwmon_device_unregister(struct device *dev)
848 {
849 	WARN_ON(devres_release(dev, devm_hwmon_release, devm_hwmon_match, dev));
850 }
851 EXPORT_SYMBOL_GPL(devm_hwmon_device_unregister);
852 
853 static void __init hwmon_pci_quirks(void)
854 {
855 #if defined CONFIG_X86 && defined CONFIG_PCI
856 	struct pci_dev *sb;
857 	u16 base;
858 	u8 enable;
859 
860 	/* Open access to 0x295-0x296 on MSI MS-7031 */
861 	sb = pci_get_device(PCI_VENDOR_ID_ATI, 0x436c, NULL);
862 	if (sb) {
863 		if (sb->subsystem_vendor == 0x1462 &&	/* MSI */
864 		    sb->subsystem_device == 0x0031) {	/* MS-7031 */
865 			pci_read_config_byte(sb, 0x48, &enable);
866 			pci_read_config_word(sb, 0x64, &base);
867 
868 			if (base == 0 && !(enable & BIT(2))) {
869 				dev_info(&sb->dev,
870 					 "Opening wide generic port at 0x295\n");
871 				pci_write_config_word(sb, 0x64, 0x295);
872 				pci_write_config_byte(sb, 0x48,
873 						      enable | BIT(2));
874 			}
875 		}
876 		pci_dev_put(sb);
877 	}
878 #endif
879 }
880 
881 static int __init hwmon_init(void)
882 {
883 	int err;
884 
885 	hwmon_pci_quirks();
886 
887 	err = class_register(&hwmon_class);
888 	if (err) {
889 		pr_err("couldn't register hwmon sysfs class\n");
890 		return err;
891 	}
892 	return 0;
893 }
894 
895 static void __exit hwmon_exit(void)
896 {
897 	class_unregister(&hwmon_class);
898 }
899 
900 subsys_initcall(hwmon_init);
901 module_exit(hwmon_exit);
902 
903 MODULE_AUTHOR("Mark M. Hoffman <mhoffman@lightlink.com>");
904 MODULE_DESCRIPTION("hardware monitoring sysfs/class support");
905 MODULE_LICENSE("GPL");
906 
907