xref: /linux/drivers/hwmon/hwmon.c (revision 2dbc0838bcf24ca59cabc3130cf3b1d6809cdcd4)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * hwmon.c - part of lm_sensors, Linux kernel modules for hardware monitoring
4  *
5  * This file defines the sysfs class "hwmon", for use by sensors drivers.
6  *
7  * Copyright (C) 2005 Mark M. Hoffman <mhoffman@lightlink.com>
8  */
9 
10 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
11 
12 #include <linux/bitops.h>
13 #include <linux/device.h>
14 #include <linux/err.h>
15 #include <linux/gfp.h>
16 #include <linux/hwmon.h>
17 #include <linux/idr.h>
18 #include <linux/module.h>
19 #include <linux/pci.h>
20 #include <linux/slab.h>
21 #include <linux/string.h>
22 #include <linux/thermal.h>
23 
24 #define CREATE_TRACE_POINTS
25 #include <trace/events/hwmon.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 #ifdef CONFIG_THERMAL_OF
119 static int hwmon_thermal_get_temp(void *data, int *temp)
120 {
121 	struct hwmon_thermal_data *tdata = data;
122 	struct hwmon_device *hwdev = tdata->hwdev;
123 	int ret;
124 	long t;
125 
126 	ret = hwdev->chip->ops->read(&hwdev->dev, hwmon_temp, hwmon_temp_input,
127 				     tdata->index, &t);
128 	if (ret < 0)
129 		return ret;
130 
131 	*temp = t;
132 
133 	return 0;
134 }
135 
136 static const struct thermal_zone_of_device_ops hwmon_thermal_ops = {
137 	.get_temp = hwmon_thermal_get_temp,
138 };
139 
140 static int hwmon_thermal_add_sensor(struct device *dev,
141 				    struct hwmon_device *hwdev, int index)
142 {
143 	struct hwmon_thermal_data *tdata;
144 	struct thermal_zone_device *tzd;
145 
146 	tdata = devm_kzalloc(dev, sizeof(*tdata), GFP_KERNEL);
147 	if (!tdata)
148 		return -ENOMEM;
149 
150 	tdata->hwdev = hwdev;
151 	tdata->index = index;
152 
153 	tzd = devm_thermal_zone_of_sensor_register(&hwdev->dev, index, tdata,
154 						   &hwmon_thermal_ops);
155 	/*
156 	 * If CONFIG_THERMAL_OF is disabled, this returns -ENODEV,
157 	 * so ignore that error but forward any other error.
158 	 */
159 	if (IS_ERR(tzd) && (PTR_ERR(tzd) != -ENODEV))
160 		return PTR_ERR(tzd);
161 
162 	return 0;
163 }
164 #else
165 static int hwmon_thermal_add_sensor(struct device *dev,
166 				    struct hwmon_device *hwdev, int index)
167 {
168 	return 0;
169 }
170 #endif /* IS_REACHABLE(CONFIG_THERMAL) && ... */
171 
172 static int hwmon_attr_base(enum hwmon_sensor_types type)
173 {
174 	if (type == hwmon_in)
175 		return 0;
176 	return 1;
177 }
178 
179 /* sysfs attribute management */
180 
181 static ssize_t hwmon_attr_show(struct device *dev,
182 			       struct device_attribute *devattr, char *buf)
183 {
184 	struct hwmon_device_attribute *hattr = to_hwmon_attr(devattr);
185 	long val;
186 	int ret;
187 
188 	ret = hattr->ops->read(dev, hattr->type, hattr->attr, hattr->index,
189 			       &val);
190 	if (ret < 0)
191 		return ret;
192 
193 	trace_hwmon_attr_show(hattr->index + hwmon_attr_base(hattr->type),
194 			      hattr->name, val);
195 
196 	return sprintf(buf, "%ld\n", val);
197 }
198 
199 static ssize_t hwmon_attr_show_string(struct device *dev,
200 				      struct device_attribute *devattr,
201 				      char *buf)
202 {
203 	struct hwmon_device_attribute *hattr = to_hwmon_attr(devattr);
204 	enum hwmon_sensor_types type = hattr->type;
205 	const char *s;
206 	int ret;
207 
208 	ret = hattr->ops->read_string(dev, hattr->type, hattr->attr,
209 				      hattr->index, &s);
210 	if (ret < 0)
211 		return ret;
212 
213 	trace_hwmon_attr_show_string(hattr->index + hwmon_attr_base(type),
214 				     hattr->name, s);
215 
216 	return sprintf(buf, "%s\n", s);
217 }
218 
219 static ssize_t hwmon_attr_store(struct device *dev,
220 				struct device_attribute *devattr,
221 				const char *buf, size_t count)
222 {
223 	struct hwmon_device_attribute *hattr = to_hwmon_attr(devattr);
224 	long val;
225 	int ret;
226 
227 	ret = kstrtol(buf, 10, &val);
228 	if (ret < 0)
229 		return ret;
230 
231 	ret = hattr->ops->write(dev, hattr->type, hattr->attr, hattr->index,
232 				val);
233 	if (ret < 0)
234 		return ret;
235 
236 	trace_hwmon_attr_store(hattr->index + hwmon_attr_base(hattr->type),
237 			       hattr->name, val);
238 
239 	return count;
240 }
241 
242 static bool is_string_attr(enum hwmon_sensor_types type, u32 attr)
243 {
244 	return (type == hwmon_temp && attr == hwmon_temp_label) ||
245 	       (type == hwmon_in && attr == hwmon_in_label) ||
246 	       (type == hwmon_curr && attr == hwmon_curr_label) ||
247 	       (type == hwmon_power && attr == hwmon_power_label) ||
248 	       (type == hwmon_energy && attr == hwmon_energy_label) ||
249 	       (type == hwmon_humidity && attr == hwmon_humidity_label) ||
250 	       (type == hwmon_fan && attr == hwmon_fan_label);
251 }
252 
253 static struct attribute *hwmon_genattr(struct device *dev,
254 				       const void *drvdata,
255 				       enum hwmon_sensor_types type,
256 				       u32 attr,
257 				       int index,
258 				       const char *template,
259 				       const struct hwmon_ops *ops)
260 {
261 	struct hwmon_device_attribute *hattr;
262 	struct device_attribute *dattr;
263 	struct attribute *a;
264 	umode_t mode;
265 	const char *name;
266 	bool is_string = is_string_attr(type, attr);
267 
268 	/* The attribute is invisible if there is no template string */
269 	if (!template)
270 		return ERR_PTR(-ENOENT);
271 
272 	mode = ops->is_visible(drvdata, type, attr, index);
273 	if (!mode)
274 		return ERR_PTR(-ENOENT);
275 
276 	if ((mode & 0444) && ((is_string && !ops->read_string) ||
277 				 (!is_string && !ops->read)))
278 		return ERR_PTR(-EINVAL);
279 	if ((mode & 0222) && !ops->write)
280 		return ERR_PTR(-EINVAL);
281 
282 	hattr = devm_kzalloc(dev, sizeof(*hattr), GFP_KERNEL);
283 	if (!hattr)
284 		return ERR_PTR(-ENOMEM);
285 
286 	if (type == hwmon_chip) {
287 		name = template;
288 	} else {
289 		scnprintf(hattr->name, sizeof(hattr->name), template,
290 			  index + hwmon_attr_base(type));
291 		name = hattr->name;
292 	}
293 
294 	hattr->type = type;
295 	hattr->attr = attr;
296 	hattr->index = index;
297 	hattr->ops = ops;
298 
299 	dattr = &hattr->dev_attr;
300 	dattr->show = is_string ? hwmon_attr_show_string : hwmon_attr_show;
301 	dattr->store = hwmon_attr_store;
302 
303 	a = &dattr->attr;
304 	sysfs_attr_init(a);
305 	a->name = name;
306 	a->mode = mode;
307 
308 	return a;
309 }
310 
311 /*
312  * Chip attributes are not attribute templates but actual sysfs attributes.
313  * See hwmon_genattr() for special handling.
314  */
315 static const char * const hwmon_chip_attrs[] = {
316 	[hwmon_chip_temp_reset_history] = "temp_reset_history",
317 	[hwmon_chip_in_reset_history] = "in_reset_history",
318 	[hwmon_chip_curr_reset_history] = "curr_reset_history",
319 	[hwmon_chip_power_reset_history] = "power_reset_history",
320 	[hwmon_chip_update_interval] = "update_interval",
321 	[hwmon_chip_alarms] = "alarms",
322 	[hwmon_chip_samples] = "samples",
323 	[hwmon_chip_curr_samples] = "curr_samples",
324 	[hwmon_chip_in_samples] = "in_samples",
325 	[hwmon_chip_power_samples] = "power_samples",
326 	[hwmon_chip_temp_samples] = "temp_samples",
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 && dev->of_node && 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 						/*
655 						 * Don't worry about hwdev;
656 						 * hwmon_dev_release(), called
657 						 * from device_unregister(),
658 						 * will free it.
659 						 */
660 						goto ida_remove;
661 					}
662 				}
663 			}
664 		}
665 	}
666 
667 	return hdev;
668 
669 free_hwmon:
670 	kfree(hwdev);
671 ida_remove:
672 	ida_simple_remove(&hwmon_ida, id);
673 	return ERR_PTR(err);
674 }
675 
676 /**
677  * hwmon_device_register_with_groups - register w/ hwmon
678  * @dev: the parent device
679  * @name: hwmon name attribute
680  * @drvdata: driver data to attach to created device
681  * @groups: List of attribute groups to create
682  *
683  * hwmon_device_unregister() must be called when the device is no
684  * longer needed.
685  *
686  * Returns the pointer to the new device.
687  */
688 struct device *
689 hwmon_device_register_with_groups(struct device *dev, const char *name,
690 				  void *drvdata,
691 				  const struct attribute_group **groups)
692 {
693 	if (!name)
694 		return ERR_PTR(-EINVAL);
695 
696 	return __hwmon_device_register(dev, name, drvdata, NULL, groups);
697 }
698 EXPORT_SYMBOL_GPL(hwmon_device_register_with_groups);
699 
700 /**
701  * hwmon_device_register_with_info - register w/ hwmon
702  * @dev: the parent device
703  * @name: hwmon name attribute
704  * @drvdata: driver data to attach to created device
705  * @chip: pointer to hwmon chip information
706  * @extra_groups: pointer to list of additional non-standard attribute groups
707  *
708  * hwmon_device_unregister() must be called when the device is no
709  * longer needed.
710  *
711  * Returns the pointer to the new device.
712  */
713 struct device *
714 hwmon_device_register_with_info(struct device *dev, const char *name,
715 				void *drvdata,
716 				const struct hwmon_chip_info *chip,
717 				const struct attribute_group **extra_groups)
718 {
719 	if (!name)
720 		return ERR_PTR(-EINVAL);
721 
722 	if (chip && (!chip->ops || !chip->ops->is_visible || !chip->info))
723 		return ERR_PTR(-EINVAL);
724 
725 	if (chip && !dev)
726 		return ERR_PTR(-EINVAL);
727 
728 	return __hwmon_device_register(dev, name, drvdata, chip, extra_groups);
729 }
730 EXPORT_SYMBOL_GPL(hwmon_device_register_with_info);
731 
732 /**
733  * hwmon_device_register - register w/ hwmon
734  * @dev: the device to register
735  *
736  * hwmon_device_unregister() must be called when the device is no
737  * longer needed.
738  *
739  * Returns the pointer to the new device.
740  */
741 struct device *hwmon_device_register(struct device *dev)
742 {
743 	dev_warn(dev,
744 		 "hwmon_device_register() is deprecated. Please convert the driver to use hwmon_device_register_with_info().\n");
745 
746 	return __hwmon_device_register(dev, NULL, NULL, NULL, NULL);
747 }
748 EXPORT_SYMBOL_GPL(hwmon_device_register);
749 
750 /**
751  * hwmon_device_unregister - removes the previously registered class device
752  *
753  * @dev: the class device to destroy
754  */
755 void hwmon_device_unregister(struct device *dev)
756 {
757 	int id;
758 
759 	if (likely(sscanf(dev_name(dev), HWMON_ID_FORMAT, &id) == 1)) {
760 		device_unregister(dev);
761 		ida_simple_remove(&hwmon_ida, id);
762 	} else
763 		dev_dbg(dev->parent,
764 			"hwmon_device_unregister() failed: bad class ID!\n");
765 }
766 EXPORT_SYMBOL_GPL(hwmon_device_unregister);
767 
768 static void devm_hwmon_release(struct device *dev, void *res)
769 {
770 	struct device *hwdev = *(struct device **)res;
771 
772 	hwmon_device_unregister(hwdev);
773 }
774 
775 /**
776  * devm_hwmon_device_register_with_groups - register w/ hwmon
777  * @dev: the parent device
778  * @name: hwmon name attribute
779  * @drvdata: driver data to attach to created device
780  * @groups: List of attribute groups to create
781  *
782  * Returns the pointer to the new device. The new device is automatically
783  * unregistered with the parent device.
784  */
785 struct device *
786 devm_hwmon_device_register_with_groups(struct device *dev, const char *name,
787 				       void *drvdata,
788 				       const struct attribute_group **groups)
789 {
790 	struct device **ptr, *hwdev;
791 
792 	if (!dev)
793 		return ERR_PTR(-EINVAL);
794 
795 	ptr = devres_alloc(devm_hwmon_release, sizeof(*ptr), GFP_KERNEL);
796 	if (!ptr)
797 		return ERR_PTR(-ENOMEM);
798 
799 	hwdev = hwmon_device_register_with_groups(dev, name, drvdata, groups);
800 	if (IS_ERR(hwdev))
801 		goto error;
802 
803 	*ptr = hwdev;
804 	devres_add(dev, ptr);
805 	return hwdev;
806 
807 error:
808 	devres_free(ptr);
809 	return hwdev;
810 }
811 EXPORT_SYMBOL_GPL(devm_hwmon_device_register_with_groups);
812 
813 /**
814  * devm_hwmon_device_register_with_info - register w/ hwmon
815  * @dev:	the parent device
816  * @name:	hwmon name attribute
817  * @drvdata:	driver data to attach to created device
818  * @chip:	pointer to hwmon chip information
819  * @groups:	pointer to list of driver specific attribute groups
820  *
821  * Returns the pointer to the new device. The new device is automatically
822  * unregistered with the parent device.
823  */
824 struct device *
825 devm_hwmon_device_register_with_info(struct device *dev, const char *name,
826 				     void *drvdata,
827 				     const struct hwmon_chip_info *chip,
828 				     const struct attribute_group **groups)
829 {
830 	struct device **ptr, *hwdev;
831 
832 	if (!dev)
833 		return ERR_PTR(-EINVAL);
834 
835 	ptr = devres_alloc(devm_hwmon_release, sizeof(*ptr), GFP_KERNEL);
836 	if (!ptr)
837 		return ERR_PTR(-ENOMEM);
838 
839 	hwdev = hwmon_device_register_with_info(dev, name, drvdata, chip,
840 						groups);
841 	if (IS_ERR(hwdev))
842 		goto error;
843 
844 	*ptr = hwdev;
845 	devres_add(dev, ptr);
846 
847 	return hwdev;
848 
849 error:
850 	devres_free(ptr);
851 	return hwdev;
852 }
853 EXPORT_SYMBOL_GPL(devm_hwmon_device_register_with_info);
854 
855 static int devm_hwmon_match(struct device *dev, void *res, void *data)
856 {
857 	struct device **hwdev = res;
858 
859 	return *hwdev == data;
860 }
861 
862 /**
863  * devm_hwmon_device_unregister - removes a previously registered hwmon device
864  *
865  * @dev: the parent device of the device to unregister
866  */
867 void devm_hwmon_device_unregister(struct device *dev)
868 {
869 	WARN_ON(devres_release(dev, devm_hwmon_release, devm_hwmon_match, dev));
870 }
871 EXPORT_SYMBOL_GPL(devm_hwmon_device_unregister);
872 
873 static void __init hwmon_pci_quirks(void)
874 {
875 #if defined CONFIG_X86 && defined CONFIG_PCI
876 	struct pci_dev *sb;
877 	u16 base;
878 	u8 enable;
879 
880 	/* Open access to 0x295-0x296 on MSI MS-7031 */
881 	sb = pci_get_device(PCI_VENDOR_ID_ATI, 0x436c, NULL);
882 	if (sb) {
883 		if (sb->subsystem_vendor == 0x1462 &&	/* MSI */
884 		    sb->subsystem_device == 0x0031) {	/* MS-7031 */
885 			pci_read_config_byte(sb, 0x48, &enable);
886 			pci_read_config_word(sb, 0x64, &base);
887 
888 			if (base == 0 && !(enable & BIT(2))) {
889 				dev_info(&sb->dev,
890 					 "Opening wide generic port at 0x295\n");
891 				pci_write_config_word(sb, 0x64, 0x295);
892 				pci_write_config_byte(sb, 0x48,
893 						      enable | BIT(2));
894 			}
895 		}
896 		pci_dev_put(sb);
897 	}
898 #endif
899 }
900 
901 static int __init hwmon_init(void)
902 {
903 	int err;
904 
905 	hwmon_pci_quirks();
906 
907 	err = class_register(&hwmon_class);
908 	if (err) {
909 		pr_err("couldn't register hwmon sysfs class\n");
910 		return err;
911 	}
912 	return 0;
913 }
914 
915 static void __exit hwmon_exit(void)
916 {
917 	class_unregister(&hwmon_class);
918 }
919 
920 subsys_initcall(hwmon_init);
921 module_exit(hwmon_exit);
922 
923 MODULE_AUTHOR("Mark M. Hoffman <mhoffman@lightlink.com>");
924 MODULE_DESCRIPTION("hardware monitoring sysfs/class support");
925 MODULE_LICENSE("GPL");
926 
927