xref: /openbmc/linux/drivers/hwmon/hwmon.c (revision 9b93eb47)
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 #ifdef CONFIG_THERMAL_OF
122 static int hwmon_thermal_get_temp(void *data, int *temp)
123 {
124 	struct hwmon_thermal_data *tdata = data;
125 	struct hwmon_device *hwdev = tdata->hwdev;
126 	int ret;
127 	long t;
128 
129 	ret = hwdev->chip->ops->read(&hwdev->dev, hwmon_temp, hwmon_temp_input,
130 				     tdata->index, &t);
131 	if (ret < 0)
132 		return ret;
133 
134 	*temp = t;
135 
136 	return 0;
137 }
138 
139 static const struct thermal_zone_of_device_ops hwmon_thermal_ops = {
140 	.get_temp = hwmon_thermal_get_temp,
141 };
142 
143 static int hwmon_thermal_add_sensor(struct device *dev,
144 				    struct hwmon_device *hwdev, int index)
145 {
146 	struct hwmon_thermal_data *tdata;
147 	struct thermal_zone_device *tzd;
148 
149 	tdata = devm_kzalloc(dev, sizeof(*tdata), GFP_KERNEL);
150 	if (!tdata)
151 		return -ENOMEM;
152 
153 	tdata->hwdev = hwdev;
154 	tdata->index = index;
155 
156 	tzd = devm_thermal_zone_of_sensor_register(&hwdev->dev, index, tdata,
157 						   &hwmon_thermal_ops);
158 	/*
159 	 * If CONFIG_THERMAL_OF is disabled, this returns -ENODEV,
160 	 * so ignore that error but forward any other error.
161 	 */
162 	if (IS_ERR(tzd) && (PTR_ERR(tzd) != -ENODEV))
163 		return PTR_ERR(tzd);
164 
165 	return 0;
166 }
167 #else
168 static int hwmon_thermal_add_sensor(struct device *dev,
169 				    struct hwmon_device *hwdev, int index)
170 {
171 	return 0;
172 }
173 #endif /* IS_REACHABLE(CONFIG_THERMAL) && ... */
174 
175 static int hwmon_attr_base(enum hwmon_sensor_types type)
176 {
177 	if (type == hwmon_in)
178 		return 0;
179 	return 1;
180 }
181 
182 /* sysfs attribute management */
183 
184 static ssize_t hwmon_attr_show(struct device *dev,
185 			       struct device_attribute *devattr, char *buf)
186 {
187 	struct hwmon_device_attribute *hattr = to_hwmon_attr(devattr);
188 	long val;
189 	int ret;
190 
191 	ret = hattr->ops->read(dev, hattr->type, hattr->attr, hattr->index,
192 			       &val);
193 	if (ret < 0)
194 		return ret;
195 
196 	trace_hwmon_attr_show(hattr->index + hwmon_attr_base(hattr->type),
197 			      hattr->name, val);
198 
199 	return sprintf(buf, "%ld\n", val);
200 }
201 
202 static ssize_t hwmon_attr_show_string(struct device *dev,
203 				      struct device_attribute *devattr,
204 				      char *buf)
205 {
206 	struct hwmon_device_attribute *hattr = to_hwmon_attr(devattr);
207 	enum hwmon_sensor_types type = hattr->type;
208 	const char *s;
209 	int ret;
210 
211 	ret = hattr->ops->read_string(dev, hattr->type, hattr->attr,
212 				      hattr->index, &s);
213 	if (ret < 0)
214 		return ret;
215 
216 	trace_hwmon_attr_show_string(hattr->index + hwmon_attr_base(type),
217 				     hattr->name, s);
218 
219 	return sprintf(buf, "%s\n", s);
220 }
221 
222 static ssize_t hwmon_attr_store(struct device *dev,
223 				struct device_attribute *devattr,
224 				const char *buf, size_t count)
225 {
226 	struct hwmon_device_attribute *hattr = to_hwmon_attr(devattr);
227 	long val;
228 	int ret;
229 
230 	ret = kstrtol(buf, 10, &val);
231 	if (ret < 0)
232 		return ret;
233 
234 	ret = hattr->ops->write(dev, hattr->type, hattr->attr, hattr->index,
235 				val);
236 	if (ret < 0)
237 		return ret;
238 
239 	trace_hwmon_attr_store(hattr->index + hwmon_attr_base(hattr->type),
240 			       hattr->name, val);
241 
242 	return count;
243 }
244 
245 static bool is_string_attr(enum hwmon_sensor_types type, u32 attr)
246 {
247 	return (type == hwmon_temp && attr == hwmon_temp_label) ||
248 	       (type == hwmon_in && attr == hwmon_in_label) ||
249 	       (type == hwmon_curr && attr == hwmon_curr_label) ||
250 	       (type == hwmon_power && attr == hwmon_power_label) ||
251 	       (type == hwmon_energy && attr == hwmon_energy_label) ||
252 	       (type == hwmon_humidity && attr == hwmon_humidity_label) ||
253 	       (type == hwmon_fan && attr == hwmon_fan_label);
254 }
255 
256 static struct attribute *hwmon_genattr(struct device *dev,
257 				       const void *drvdata,
258 				       enum hwmon_sensor_types type,
259 				       u32 attr,
260 				       int index,
261 				       const char *template,
262 				       const struct hwmon_ops *ops)
263 {
264 	struct hwmon_device_attribute *hattr;
265 	struct device_attribute *dattr;
266 	struct attribute *a;
267 	umode_t mode;
268 	const char *name;
269 	bool is_string = is_string_attr(type, attr);
270 
271 	/* The attribute is invisible if there is no template string */
272 	if (!template)
273 		return ERR_PTR(-ENOENT);
274 
275 	mode = ops->is_visible(drvdata, type, attr, index);
276 	if (!mode)
277 		return ERR_PTR(-ENOENT);
278 
279 	if ((mode & 0444) && ((is_string && !ops->read_string) ||
280 				 (!is_string && !ops->read)))
281 		return ERR_PTR(-EINVAL);
282 	if ((mode & 0222) && !ops->write)
283 		return ERR_PTR(-EINVAL);
284 
285 	hattr = devm_kzalloc(dev, sizeof(*hattr), GFP_KERNEL);
286 	if (!hattr)
287 		return ERR_PTR(-ENOMEM);
288 
289 	if (type == hwmon_chip) {
290 		name = template;
291 	} else {
292 		scnprintf(hattr->name, sizeof(hattr->name), template,
293 			  index + hwmon_attr_base(type));
294 		name = hattr->name;
295 	}
296 
297 	hattr->type = type;
298 	hattr->attr = attr;
299 	hattr->index = index;
300 	hattr->ops = ops;
301 
302 	dattr = &hattr->dev_attr;
303 	dattr->show = is_string ? hwmon_attr_show_string : hwmon_attr_show;
304 	dattr->store = hwmon_attr_store;
305 
306 	a = &dattr->attr;
307 	sysfs_attr_init(a);
308 	a->name = name;
309 	a->mode = mode;
310 
311 	return a;
312 }
313 
314 /*
315  * Chip attributes are not attribute templates but actual sysfs attributes.
316  * See hwmon_genattr() for special handling.
317  */
318 static const char * const hwmon_chip_attrs[] = {
319 	[hwmon_chip_temp_reset_history] = "temp_reset_history",
320 	[hwmon_chip_in_reset_history] = "in_reset_history",
321 	[hwmon_chip_curr_reset_history] = "curr_reset_history",
322 	[hwmon_chip_power_reset_history] = "power_reset_history",
323 	[hwmon_chip_update_interval] = "update_interval",
324 	[hwmon_chip_alarms] = "alarms",
325 	[hwmon_chip_samples] = "samples",
326 	[hwmon_chip_curr_samples] = "curr_samples",
327 	[hwmon_chip_in_samples] = "in_samples",
328 	[hwmon_chip_power_samples] = "power_samples",
329 	[hwmon_chip_temp_samples] = "temp_samples",
330 };
331 
332 static const char * const hwmon_temp_attr_templates[] = {
333 	[hwmon_temp_input] = "temp%d_input",
334 	[hwmon_temp_type] = "temp%d_type",
335 	[hwmon_temp_lcrit] = "temp%d_lcrit",
336 	[hwmon_temp_lcrit_hyst] = "temp%d_lcrit_hyst",
337 	[hwmon_temp_min] = "temp%d_min",
338 	[hwmon_temp_min_hyst] = "temp%d_min_hyst",
339 	[hwmon_temp_max] = "temp%d_max",
340 	[hwmon_temp_max_hyst] = "temp%d_max_hyst",
341 	[hwmon_temp_crit] = "temp%d_crit",
342 	[hwmon_temp_crit_hyst] = "temp%d_crit_hyst",
343 	[hwmon_temp_emergency] = "temp%d_emergency",
344 	[hwmon_temp_emergency_hyst] = "temp%d_emergency_hyst",
345 	[hwmon_temp_alarm] = "temp%d_alarm",
346 	[hwmon_temp_lcrit_alarm] = "temp%d_lcrit_alarm",
347 	[hwmon_temp_min_alarm] = "temp%d_min_alarm",
348 	[hwmon_temp_max_alarm] = "temp%d_max_alarm",
349 	[hwmon_temp_crit_alarm] = "temp%d_crit_alarm",
350 	[hwmon_temp_emergency_alarm] = "temp%d_emergency_alarm",
351 	[hwmon_temp_fault] = "temp%d_fault",
352 	[hwmon_temp_offset] = "temp%d_offset",
353 	[hwmon_temp_label] = "temp%d_label",
354 	[hwmon_temp_lowest] = "temp%d_lowest",
355 	[hwmon_temp_highest] = "temp%d_highest",
356 	[hwmon_temp_reset_history] = "temp%d_reset_history",
357 };
358 
359 static const char * const hwmon_in_attr_templates[] = {
360 	[hwmon_in_input] = "in%d_input",
361 	[hwmon_in_min] = "in%d_min",
362 	[hwmon_in_max] = "in%d_max",
363 	[hwmon_in_lcrit] = "in%d_lcrit",
364 	[hwmon_in_crit] = "in%d_crit",
365 	[hwmon_in_average] = "in%d_average",
366 	[hwmon_in_lowest] = "in%d_lowest",
367 	[hwmon_in_highest] = "in%d_highest",
368 	[hwmon_in_reset_history] = "in%d_reset_history",
369 	[hwmon_in_label] = "in%d_label",
370 	[hwmon_in_alarm] = "in%d_alarm",
371 	[hwmon_in_min_alarm] = "in%d_min_alarm",
372 	[hwmon_in_max_alarm] = "in%d_max_alarm",
373 	[hwmon_in_lcrit_alarm] = "in%d_lcrit_alarm",
374 	[hwmon_in_crit_alarm] = "in%d_crit_alarm",
375 	[hwmon_in_enable] = "in%d_enable",
376 };
377 
378 static const char * const hwmon_curr_attr_templates[] = {
379 	[hwmon_curr_input] = "curr%d_input",
380 	[hwmon_curr_min] = "curr%d_min",
381 	[hwmon_curr_max] = "curr%d_max",
382 	[hwmon_curr_lcrit] = "curr%d_lcrit",
383 	[hwmon_curr_crit] = "curr%d_crit",
384 	[hwmon_curr_average] = "curr%d_average",
385 	[hwmon_curr_lowest] = "curr%d_lowest",
386 	[hwmon_curr_highest] = "curr%d_highest",
387 	[hwmon_curr_reset_history] = "curr%d_reset_history",
388 	[hwmon_curr_label] = "curr%d_label",
389 	[hwmon_curr_alarm] = "curr%d_alarm",
390 	[hwmon_curr_min_alarm] = "curr%d_min_alarm",
391 	[hwmon_curr_max_alarm] = "curr%d_max_alarm",
392 	[hwmon_curr_lcrit_alarm] = "curr%d_lcrit_alarm",
393 	[hwmon_curr_crit_alarm] = "curr%d_crit_alarm",
394 };
395 
396 static const char * const hwmon_power_attr_templates[] = {
397 	[hwmon_power_average] = "power%d_average",
398 	[hwmon_power_average_interval] = "power%d_average_interval",
399 	[hwmon_power_average_interval_max] = "power%d_interval_max",
400 	[hwmon_power_average_interval_min] = "power%d_interval_min",
401 	[hwmon_power_average_highest] = "power%d_average_highest",
402 	[hwmon_power_average_lowest] = "power%d_average_lowest",
403 	[hwmon_power_average_max] = "power%d_average_max",
404 	[hwmon_power_average_min] = "power%d_average_min",
405 	[hwmon_power_input] = "power%d_input",
406 	[hwmon_power_input_highest] = "power%d_input_highest",
407 	[hwmon_power_input_lowest] = "power%d_input_lowest",
408 	[hwmon_power_reset_history] = "power%d_reset_history",
409 	[hwmon_power_accuracy] = "power%d_accuracy",
410 	[hwmon_power_cap] = "power%d_cap",
411 	[hwmon_power_cap_hyst] = "power%d_cap_hyst",
412 	[hwmon_power_cap_max] = "power%d_cap_max",
413 	[hwmon_power_cap_min] = "power%d_cap_min",
414 	[hwmon_power_min] = "power%d_min",
415 	[hwmon_power_max] = "power%d_max",
416 	[hwmon_power_lcrit] = "power%d_lcrit",
417 	[hwmon_power_crit] = "power%d_crit",
418 	[hwmon_power_label] = "power%d_label",
419 	[hwmon_power_alarm] = "power%d_alarm",
420 	[hwmon_power_cap_alarm] = "power%d_cap_alarm",
421 	[hwmon_power_min_alarm] = "power%d_min_alarm",
422 	[hwmon_power_max_alarm] = "power%d_max_alarm",
423 	[hwmon_power_lcrit_alarm] = "power%d_lcrit_alarm",
424 	[hwmon_power_crit_alarm] = "power%d_crit_alarm",
425 };
426 
427 static const char * const hwmon_energy_attr_templates[] = {
428 	[hwmon_energy_input] = "energy%d_input",
429 	[hwmon_energy_label] = "energy%d_label",
430 };
431 
432 static const char * const hwmon_humidity_attr_templates[] = {
433 	[hwmon_humidity_input] = "humidity%d_input",
434 	[hwmon_humidity_label] = "humidity%d_label",
435 	[hwmon_humidity_min] = "humidity%d_min",
436 	[hwmon_humidity_min_hyst] = "humidity%d_min_hyst",
437 	[hwmon_humidity_max] = "humidity%d_max",
438 	[hwmon_humidity_max_hyst] = "humidity%d_max_hyst",
439 	[hwmon_humidity_alarm] = "humidity%d_alarm",
440 	[hwmon_humidity_fault] = "humidity%d_fault",
441 };
442 
443 static const char * const hwmon_fan_attr_templates[] = {
444 	[hwmon_fan_input] = "fan%d_input",
445 	[hwmon_fan_label] = "fan%d_label",
446 	[hwmon_fan_min] = "fan%d_min",
447 	[hwmon_fan_max] = "fan%d_max",
448 	[hwmon_fan_div] = "fan%d_div",
449 	[hwmon_fan_pulses] = "fan%d_pulses",
450 	[hwmon_fan_target] = "fan%d_target",
451 	[hwmon_fan_alarm] = "fan%d_alarm",
452 	[hwmon_fan_min_alarm] = "fan%d_min_alarm",
453 	[hwmon_fan_max_alarm] = "fan%d_max_alarm",
454 	[hwmon_fan_fault] = "fan%d_fault",
455 };
456 
457 static const char * const hwmon_pwm_attr_templates[] = {
458 	[hwmon_pwm_input] = "pwm%d",
459 	[hwmon_pwm_enable] = "pwm%d_enable",
460 	[hwmon_pwm_mode] = "pwm%d_mode",
461 	[hwmon_pwm_freq] = "pwm%d_freq",
462 };
463 
464 static const char * const *__templates[] = {
465 	[hwmon_chip] = hwmon_chip_attrs,
466 	[hwmon_temp] = hwmon_temp_attr_templates,
467 	[hwmon_in] = hwmon_in_attr_templates,
468 	[hwmon_curr] = hwmon_curr_attr_templates,
469 	[hwmon_power] = hwmon_power_attr_templates,
470 	[hwmon_energy] = hwmon_energy_attr_templates,
471 	[hwmon_humidity] = hwmon_humidity_attr_templates,
472 	[hwmon_fan] = hwmon_fan_attr_templates,
473 	[hwmon_pwm] = hwmon_pwm_attr_templates,
474 };
475 
476 static const int __templates_size[] = {
477 	[hwmon_chip] = ARRAY_SIZE(hwmon_chip_attrs),
478 	[hwmon_temp] = ARRAY_SIZE(hwmon_temp_attr_templates),
479 	[hwmon_in] = ARRAY_SIZE(hwmon_in_attr_templates),
480 	[hwmon_curr] = ARRAY_SIZE(hwmon_curr_attr_templates),
481 	[hwmon_power] = ARRAY_SIZE(hwmon_power_attr_templates),
482 	[hwmon_energy] = ARRAY_SIZE(hwmon_energy_attr_templates),
483 	[hwmon_humidity] = ARRAY_SIZE(hwmon_humidity_attr_templates),
484 	[hwmon_fan] = ARRAY_SIZE(hwmon_fan_attr_templates),
485 	[hwmon_pwm] = ARRAY_SIZE(hwmon_pwm_attr_templates),
486 };
487 
488 static int hwmon_num_channel_attrs(const struct hwmon_channel_info *info)
489 {
490 	int i, n;
491 
492 	for (i = n = 0; info->config[i]; i++)
493 		n += hweight32(info->config[i]);
494 
495 	return n;
496 }
497 
498 static int hwmon_genattrs(struct device *dev,
499 			  const void *drvdata,
500 			  struct attribute **attrs,
501 			  const struct hwmon_ops *ops,
502 			  const struct hwmon_channel_info *info)
503 {
504 	const char * const *templates;
505 	int template_size;
506 	int i, aindex = 0;
507 
508 	if (info->type >= ARRAY_SIZE(__templates))
509 		return -EINVAL;
510 
511 	templates = __templates[info->type];
512 	template_size = __templates_size[info->type];
513 
514 	for (i = 0; info->config[i]; i++) {
515 		u32 attr_mask = info->config[i];
516 		u32 attr;
517 
518 		while (attr_mask) {
519 			struct attribute *a;
520 
521 			attr = __ffs(attr_mask);
522 			attr_mask &= ~BIT(attr);
523 			if (attr >= template_size)
524 				return -EINVAL;
525 			a = hwmon_genattr(dev, drvdata, info->type, attr, i,
526 					  templates[attr], ops);
527 			if (IS_ERR(a)) {
528 				if (PTR_ERR(a) != -ENOENT)
529 					return PTR_ERR(a);
530 				continue;
531 			}
532 			attrs[aindex++] = a;
533 		}
534 	}
535 	return aindex;
536 }
537 
538 static struct attribute **
539 __hwmon_create_attrs(struct device *dev, const void *drvdata,
540 		     const struct hwmon_chip_info *chip)
541 {
542 	int ret, i, aindex = 0, nattrs = 0;
543 	struct attribute **attrs;
544 
545 	for (i = 0; chip->info[i]; i++)
546 		nattrs += hwmon_num_channel_attrs(chip->info[i]);
547 
548 	if (nattrs == 0)
549 		return ERR_PTR(-EINVAL);
550 
551 	attrs = devm_kcalloc(dev, nattrs + 1, sizeof(*attrs), GFP_KERNEL);
552 	if (!attrs)
553 		return ERR_PTR(-ENOMEM);
554 
555 	for (i = 0; chip->info[i]; i++) {
556 		ret = hwmon_genattrs(dev, drvdata, &attrs[aindex], chip->ops,
557 				     chip->info[i]);
558 		if (ret < 0)
559 			return ERR_PTR(ret);
560 		aindex += ret;
561 	}
562 
563 	return attrs;
564 }
565 
566 static struct device *
567 __hwmon_device_register(struct device *dev, const char *name, void *drvdata,
568 			const struct hwmon_chip_info *chip,
569 			const struct attribute_group **groups)
570 {
571 	struct hwmon_device *hwdev;
572 	struct device *hdev;
573 	int i, j, err, id;
574 
575 	/* Complain about invalid characters in hwmon name attribute */
576 	if (name && (!strlen(name) || strpbrk(name, "-* \t\n")))
577 		dev_warn(dev,
578 			 "hwmon: '%s' is not a valid name attribute, please fix\n",
579 			 name);
580 
581 	id = ida_simple_get(&hwmon_ida, 0, 0, GFP_KERNEL);
582 	if (id < 0)
583 		return ERR_PTR(id);
584 
585 	hwdev = kzalloc(sizeof(*hwdev), GFP_KERNEL);
586 	if (hwdev == NULL) {
587 		err = -ENOMEM;
588 		goto ida_remove;
589 	}
590 
591 	hdev = &hwdev->dev;
592 
593 	if (chip) {
594 		struct attribute **attrs;
595 		int ngroups = 2; /* terminating NULL plus &hwdev->groups */
596 
597 		if (groups)
598 			for (i = 0; groups[i]; i++)
599 				ngroups++;
600 
601 		hwdev->groups = devm_kcalloc(dev, ngroups, sizeof(*groups),
602 					     GFP_KERNEL);
603 		if (!hwdev->groups) {
604 			err = -ENOMEM;
605 			goto free_hwmon;
606 		}
607 
608 		attrs = __hwmon_create_attrs(dev, drvdata, chip);
609 		if (IS_ERR(attrs)) {
610 			err = PTR_ERR(attrs);
611 			goto free_hwmon;
612 		}
613 
614 		hwdev->group.attrs = attrs;
615 		ngroups = 0;
616 		hwdev->groups[ngroups++] = &hwdev->group;
617 
618 		if (groups) {
619 			for (i = 0; groups[i]; i++)
620 				hwdev->groups[ngroups++] = groups[i];
621 		}
622 
623 		hdev->groups = hwdev->groups;
624 	} else {
625 		hdev->groups = groups;
626 	}
627 
628 	hwdev->name = name;
629 	hdev->class = &hwmon_class;
630 	hdev->parent = dev;
631 	hdev->of_node = dev ? dev->of_node : NULL;
632 	hwdev->chip = chip;
633 	dev_set_drvdata(hdev, drvdata);
634 	dev_set_name(hdev, HWMON_ID_FORMAT, id);
635 	err = device_register(hdev);
636 	if (err)
637 		goto free_hwmon;
638 
639 	if (dev && chip && chip->ops->read &&
640 	    chip->info[0]->type == hwmon_chip &&
641 	    (chip->info[0]->config[0] & HWMON_C_REGISTER_TZ)) {
642 		const struct hwmon_channel_info **info = chip->info;
643 
644 		for (i = 1; info[i]; i++) {
645 			if (info[i]->type != hwmon_temp)
646 				continue;
647 
648 			for (j = 0; info[i]->config[j]; j++) {
649 				if (!chip->ops->is_visible(drvdata, hwmon_temp,
650 							   hwmon_temp_input, j))
651 					continue;
652 				if (info[i]->config[j] & HWMON_T_INPUT) {
653 					err = hwmon_thermal_add_sensor(dev,
654 								hwdev, j);
655 					if (err) {
656 						device_unregister(hdev);
657 						goto ida_remove;
658 					}
659 				}
660 			}
661 		}
662 	}
663 
664 	return hdev;
665 
666 free_hwmon:
667 	kfree(hwdev);
668 ida_remove:
669 	ida_simple_remove(&hwmon_ida, id);
670 	return ERR_PTR(err);
671 }
672 
673 /**
674  * hwmon_device_register_with_groups - register w/ hwmon
675  * @dev: the parent device
676  * @name: hwmon name attribute
677  * @drvdata: driver data to attach to created device
678  * @groups: List of attribute groups to create
679  *
680  * hwmon_device_unregister() must be called when the device is no
681  * longer needed.
682  *
683  * Returns the pointer to the new device.
684  */
685 struct device *
686 hwmon_device_register_with_groups(struct device *dev, const char *name,
687 				  void *drvdata,
688 				  const struct attribute_group **groups)
689 {
690 	if (!name)
691 		return ERR_PTR(-EINVAL);
692 
693 	return __hwmon_device_register(dev, name, drvdata, NULL, groups);
694 }
695 EXPORT_SYMBOL_GPL(hwmon_device_register_with_groups);
696 
697 /**
698  * hwmon_device_register_with_info - register w/ hwmon
699  * @dev: the parent device
700  * @name: hwmon name attribute
701  * @drvdata: driver data to attach to created device
702  * @chip: pointer to hwmon chip information
703  * @extra_groups: pointer to list of additional non-standard attribute groups
704  *
705  * hwmon_device_unregister() must be called when the device is no
706  * longer needed.
707  *
708  * Returns the pointer to the new device.
709  */
710 struct device *
711 hwmon_device_register_with_info(struct device *dev, const char *name,
712 				void *drvdata,
713 				const struct hwmon_chip_info *chip,
714 				const struct attribute_group **extra_groups)
715 {
716 	if (!name)
717 		return ERR_PTR(-EINVAL);
718 
719 	if (chip && (!chip->ops || !chip->ops->is_visible || !chip->info))
720 		return ERR_PTR(-EINVAL);
721 
722 	if (chip && !dev)
723 		return ERR_PTR(-EINVAL);
724 
725 	return __hwmon_device_register(dev, name, drvdata, chip, extra_groups);
726 }
727 EXPORT_SYMBOL_GPL(hwmon_device_register_with_info);
728 
729 /**
730  * hwmon_device_register - register w/ hwmon
731  * @dev: the device to register
732  *
733  * hwmon_device_unregister() must be called when the device is no
734  * longer needed.
735  *
736  * Returns the pointer to the new device.
737  */
738 struct device *hwmon_device_register(struct device *dev)
739 {
740 	dev_warn(dev,
741 		 "hwmon_device_register() is deprecated. Please convert the driver to use hwmon_device_register_with_info().\n");
742 
743 	return __hwmon_device_register(dev, NULL, NULL, NULL, NULL);
744 }
745 EXPORT_SYMBOL_GPL(hwmon_device_register);
746 
747 /**
748  * hwmon_device_unregister - removes the previously registered class device
749  *
750  * @dev: the class device to destroy
751  */
752 void hwmon_device_unregister(struct device *dev)
753 {
754 	int id;
755 
756 	if (likely(sscanf(dev_name(dev), HWMON_ID_FORMAT, &id) == 1)) {
757 		device_unregister(dev);
758 		ida_simple_remove(&hwmon_ida, id);
759 	} else
760 		dev_dbg(dev->parent,
761 			"hwmon_device_unregister() failed: bad class ID!\n");
762 }
763 EXPORT_SYMBOL_GPL(hwmon_device_unregister);
764 
765 static void devm_hwmon_release(struct device *dev, void *res)
766 {
767 	struct device *hwdev = *(struct device **)res;
768 
769 	hwmon_device_unregister(hwdev);
770 }
771 
772 /**
773  * devm_hwmon_device_register_with_groups - register w/ hwmon
774  * @dev: the parent device
775  * @name: hwmon name attribute
776  * @drvdata: driver data to attach to created device
777  * @groups: List of attribute groups to create
778  *
779  * Returns the pointer to the new device. The new device is automatically
780  * unregistered with the parent device.
781  */
782 struct device *
783 devm_hwmon_device_register_with_groups(struct device *dev, const char *name,
784 				       void *drvdata,
785 				       const struct attribute_group **groups)
786 {
787 	struct device **ptr, *hwdev;
788 
789 	if (!dev)
790 		return ERR_PTR(-EINVAL);
791 
792 	ptr = devres_alloc(devm_hwmon_release, sizeof(*ptr), GFP_KERNEL);
793 	if (!ptr)
794 		return ERR_PTR(-ENOMEM);
795 
796 	hwdev = hwmon_device_register_with_groups(dev, name, drvdata, groups);
797 	if (IS_ERR(hwdev))
798 		goto error;
799 
800 	*ptr = hwdev;
801 	devres_add(dev, ptr);
802 	return hwdev;
803 
804 error:
805 	devres_free(ptr);
806 	return hwdev;
807 }
808 EXPORT_SYMBOL_GPL(devm_hwmon_device_register_with_groups);
809 
810 /**
811  * devm_hwmon_device_register_with_info - register w/ hwmon
812  * @dev:	the parent device
813  * @name:	hwmon name attribute
814  * @drvdata:	driver data to attach to created device
815  * @chip:	pointer to hwmon chip information
816  * @groups:	pointer to list of driver specific attribute groups
817  *
818  * Returns the pointer to the new device. The new device is automatically
819  * unregistered with the parent device.
820  */
821 struct device *
822 devm_hwmon_device_register_with_info(struct device *dev, const char *name,
823 				     void *drvdata,
824 				     const struct hwmon_chip_info *chip,
825 				     const struct attribute_group **groups)
826 {
827 	struct device **ptr, *hwdev;
828 
829 	if (!dev)
830 		return ERR_PTR(-EINVAL);
831 
832 	ptr = devres_alloc(devm_hwmon_release, sizeof(*ptr), GFP_KERNEL);
833 	if (!ptr)
834 		return ERR_PTR(-ENOMEM);
835 
836 	hwdev = hwmon_device_register_with_info(dev, name, drvdata, chip,
837 						groups);
838 	if (IS_ERR(hwdev))
839 		goto error;
840 
841 	*ptr = hwdev;
842 	devres_add(dev, ptr);
843 
844 	return hwdev;
845 
846 error:
847 	devres_free(ptr);
848 	return hwdev;
849 }
850 EXPORT_SYMBOL_GPL(devm_hwmon_device_register_with_info);
851 
852 static int devm_hwmon_match(struct device *dev, void *res, void *data)
853 {
854 	struct device **hwdev = res;
855 
856 	return *hwdev == data;
857 }
858 
859 /**
860  * devm_hwmon_device_unregister - removes a previously registered hwmon device
861  *
862  * @dev: the parent device of the device to unregister
863  */
864 void devm_hwmon_device_unregister(struct device *dev)
865 {
866 	WARN_ON(devres_release(dev, devm_hwmon_release, devm_hwmon_match, dev));
867 }
868 EXPORT_SYMBOL_GPL(devm_hwmon_device_unregister);
869 
870 static void __init hwmon_pci_quirks(void)
871 {
872 #if defined CONFIG_X86 && defined CONFIG_PCI
873 	struct pci_dev *sb;
874 	u16 base;
875 	u8 enable;
876 
877 	/* Open access to 0x295-0x296 on MSI MS-7031 */
878 	sb = pci_get_device(PCI_VENDOR_ID_ATI, 0x436c, NULL);
879 	if (sb) {
880 		if (sb->subsystem_vendor == 0x1462 &&	/* MSI */
881 		    sb->subsystem_device == 0x0031) {	/* MS-7031 */
882 			pci_read_config_byte(sb, 0x48, &enable);
883 			pci_read_config_word(sb, 0x64, &base);
884 
885 			if (base == 0 && !(enable & BIT(2))) {
886 				dev_info(&sb->dev,
887 					 "Opening wide generic port at 0x295\n");
888 				pci_write_config_word(sb, 0x64, 0x295);
889 				pci_write_config_byte(sb, 0x48,
890 						      enable | BIT(2));
891 			}
892 		}
893 		pci_dev_put(sb);
894 	}
895 #endif
896 }
897 
898 static int __init hwmon_init(void)
899 {
900 	int err;
901 
902 	hwmon_pci_quirks();
903 
904 	err = class_register(&hwmon_class);
905 	if (err) {
906 		pr_err("couldn't register hwmon sysfs class\n");
907 		return err;
908 	}
909 	return 0;
910 }
911 
912 static void __exit hwmon_exit(void)
913 {
914 	class_unregister(&hwmon_class);
915 }
916 
917 subsys_initcall(hwmon_init);
918 module_exit(hwmon_exit);
919 
920 MODULE_AUTHOR("Mark M. Hoffman <mhoffman@lightlink.com>");
921 MODULE_DESCRIPTION("hardware monitoring sysfs/class support");
922 MODULE_LICENSE("GPL");
923 
924