1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * A hwmon driver for ACPI 4.0 power meters
4 * Copyright (C) 2009 IBM
5 *
6 * Author: Darrick J. Wong <[email protected]>
7 */
8
9 #include <linux/module.h>
10 #include <linux/hwmon.h>
11 #include <linux/hwmon-sysfs.h>
12 #include <linux/jiffies.h>
13 #include <linux/mutex.h>
14 #include <linux/dmi.h>
15 #include <linux/slab.h>
16 #include <linux/kdev_t.h>
17 #include <linux/sched.h>
18 #include <linux/time.h>
19 #include <linux/err.h>
20 #include <linux/acpi.h>
21
22 #define ACPI_POWER_METER_NAME "power_meter"
23 #define ACPI_POWER_METER_DEVICE_NAME "Power Meter"
24 #define ACPI_POWER_METER_CLASS "pwr_meter_resource"
25
26 #define NUM_SENSORS 17
27
28 #define POWER_METER_CAN_MEASURE (1 << 0)
29 #define POWER_METER_CAN_TRIP (1 << 1)
30 #define POWER_METER_CAN_CAP (1 << 2)
31 #define POWER_METER_CAN_NOTIFY (1 << 3)
32 #define POWER_METER_IS_BATTERY (1 << 8)
33 #define UNKNOWN_HYSTERESIS 0xFFFFFFFF
34 #define UNKNOWN_POWER 0xFFFFFFFF
35
36 #define METER_NOTIFY_CONFIG 0x80
37 #define METER_NOTIFY_TRIP 0x81
38 #define METER_NOTIFY_CAP 0x82
39 #define METER_NOTIFY_CAPPING 0x83
40 #define METER_NOTIFY_INTERVAL 0x84
41
42 #define POWER_AVERAGE_NAME "power1_average"
43 #define POWER_CAP_NAME "power1_cap"
44 #define POWER_AVG_INTERVAL_NAME "power1_average_interval"
45 #define POWER_ALARM_NAME "power1_alarm"
46
47 static int cap_in_hardware;
48 static bool force_cap_on;
49
can_cap_in_hardware(void)50 static int can_cap_in_hardware(void)
51 {
52 return force_cap_on || cap_in_hardware;
53 }
54
55 static const struct acpi_device_id power_meter_ids[] = {
56 {"ACPI000D", 0},
57 {"", 0},
58 };
59 MODULE_DEVICE_TABLE(acpi, power_meter_ids);
60
61 struct acpi_power_meter_capabilities {
62 u64 flags;
63 u64 units;
64 u64 type;
65 u64 accuracy;
66 u64 sampling_time;
67 u64 min_avg_interval;
68 u64 max_avg_interval;
69 u64 hysteresis;
70 u64 configurable_cap;
71 u64 min_cap;
72 u64 max_cap;
73 };
74
75 struct acpi_power_meter_resource {
76 struct acpi_device *acpi_dev;
77 acpi_bus_id name;
78 struct mutex lock;
79 struct device *hwmon_dev;
80 struct acpi_power_meter_capabilities caps;
81 acpi_string model_number;
82 acpi_string serial_number;
83 acpi_string oem_info;
84 u64 power;
85 u64 cap;
86 u64 avg_interval;
87 bool power_alarm;
88 int sensors_valid;
89 unsigned long sensors_last_updated;
90 #define POWER_METER_TRIP_AVERAGE_MIN_IDX 0
91 #define POWER_METER_TRIP_AVERAGE_MAX_IDX 1
92 s64 trip[2];
93 int num_domain_devices;
94 struct acpi_device **domain_devices;
95 struct kobject *holders_dir;
96 };
97
98 /* Averaging interval */
update_avg_interval(struct acpi_power_meter_resource * resource)99 static int update_avg_interval(struct acpi_power_meter_resource *resource)
100 {
101 unsigned long long data;
102 acpi_status status;
103
104 status = acpi_evaluate_integer(resource->acpi_dev->handle, "_GAI",
105 NULL, &data);
106 if (ACPI_FAILURE(status)) {
107 acpi_evaluation_failure_warn(resource->acpi_dev->handle, "_GAI",
108 status);
109 return -ENODEV;
110 }
111
112 resource->avg_interval = data;
113 return 0;
114 }
115
116 /* Cap functions */
update_cap(struct acpi_power_meter_resource * resource)117 static int update_cap(struct acpi_power_meter_resource *resource)
118 {
119 unsigned long long data;
120 acpi_status status;
121
122 status = acpi_evaluate_integer(resource->acpi_dev->handle, "_GHL",
123 NULL, &data);
124 if (ACPI_FAILURE(status)) {
125 acpi_evaluation_failure_warn(resource->acpi_dev->handle, "_GHL",
126 status);
127 return -ENODEV;
128 }
129
130 resource->cap = data;
131 return 0;
132 }
133
134 /* Power meter trip points */
set_acpi_trip(struct acpi_power_meter_resource * resource)135 static int set_acpi_trip(struct acpi_power_meter_resource *resource)
136 {
137 union acpi_object arg_objs[] = {
138 {ACPI_TYPE_INTEGER},
139 {ACPI_TYPE_INTEGER}
140 };
141 struct acpi_object_list args = { 2, arg_objs };
142 unsigned long long data;
143 acpi_status status;
144
145 /* Both trip levels must be set */
146 if (resource->trip[0] < 0 || resource->trip[1] < 0)
147 return 0;
148
149 /* This driver stores min, max; ACPI wants max, min. */
150 arg_objs[0].integer.value = resource->trip[1];
151 arg_objs[1].integer.value = resource->trip[0];
152
153 status = acpi_evaluate_integer(resource->acpi_dev->handle, "_PTP",
154 &args, &data);
155 if (ACPI_FAILURE(status)) {
156 acpi_evaluation_failure_warn(resource->acpi_dev->handle, "_PTP",
157 status);
158 return -EINVAL;
159 }
160
161 /* _PTP returns 0 on success, nonzero otherwise */
162 if (data)
163 return -EINVAL;
164
165 return 0;
166 }
167
168 /* Power meter */
update_meter(struct acpi_power_meter_resource * resource)169 static int update_meter(struct acpi_power_meter_resource *resource)
170 {
171 unsigned long long data;
172 acpi_status status;
173 unsigned long local_jiffies = jiffies;
174
175 if (time_before(local_jiffies, resource->sensors_last_updated +
176 msecs_to_jiffies(resource->caps.sampling_time)) &&
177 resource->sensors_valid)
178 return 0;
179
180 status = acpi_evaluate_integer(resource->acpi_dev->handle, "_PMM",
181 NULL, &data);
182 if (ACPI_FAILURE(status)) {
183 acpi_evaluation_failure_warn(resource->acpi_dev->handle, "_PMM",
184 status);
185 return -ENODEV;
186 }
187
188 resource->power = data;
189 resource->sensors_valid = 1;
190 resource->sensors_last_updated = jiffies;
191 return 0;
192 }
193
194 /* Read power domain data */
remove_domain_devices(struct acpi_power_meter_resource * resource)195 static void remove_domain_devices(struct acpi_power_meter_resource *resource)
196 {
197 int i;
198
199 if (!resource->num_domain_devices)
200 return;
201
202 for (i = 0; i < resource->num_domain_devices; i++) {
203 struct acpi_device *obj = resource->domain_devices[i];
204
205 if (!obj)
206 continue;
207
208 sysfs_remove_link(resource->holders_dir,
209 kobject_name(&obj->dev.kobj));
210 acpi_dev_put(obj);
211 }
212
213 kfree(resource->domain_devices);
214 kobject_put(resource->holders_dir);
215 resource->num_domain_devices = 0;
216 }
217
read_domain_devices(struct acpi_power_meter_resource * resource)218 static int read_domain_devices(struct acpi_power_meter_resource *resource)
219 {
220 int res = 0;
221 int i;
222 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
223 union acpi_object *pss;
224 acpi_status status;
225
226 status = acpi_evaluate_object(resource->acpi_dev->handle, "_PMD", NULL,
227 &buffer);
228 if (ACPI_FAILURE(status)) {
229 acpi_evaluation_failure_warn(resource->acpi_dev->handle, "_PMD",
230 status);
231 return -ENODEV;
232 }
233
234 pss = buffer.pointer;
235 if (!pss ||
236 pss->type != ACPI_TYPE_PACKAGE) {
237 dev_err(&resource->acpi_dev->dev, ACPI_POWER_METER_NAME
238 "Invalid _PMD data\n");
239 res = -EFAULT;
240 goto end;
241 }
242
243 if (!pss->package.count)
244 goto end;
245
246 resource->domain_devices = kcalloc(pss->package.count,
247 sizeof(struct acpi_device *),
248 GFP_KERNEL);
249 if (!resource->domain_devices) {
250 res = -ENOMEM;
251 goto end;
252 }
253
254 resource->holders_dir = kobject_create_and_add("measures",
255 &resource->acpi_dev->dev.kobj);
256 if (!resource->holders_dir) {
257 res = -ENOMEM;
258 goto exit_free;
259 }
260
261 resource->num_domain_devices = pss->package.count;
262
263 for (i = 0; i < pss->package.count; i++) {
264 struct acpi_device *obj;
265 union acpi_object *element = &pss->package.elements[i];
266
267 /* Refuse non-references */
268 if (element->type != ACPI_TYPE_LOCAL_REFERENCE)
269 continue;
270
271 /* Create a symlink to domain objects */
272 obj = acpi_get_acpi_dev(element->reference.handle);
273 resource->domain_devices[i] = obj;
274 if (!obj)
275 continue;
276
277 res = sysfs_create_link(resource->holders_dir, &obj->dev.kobj,
278 kobject_name(&obj->dev.kobj));
279 if (res) {
280 acpi_dev_put(obj);
281 resource->domain_devices[i] = NULL;
282 }
283 }
284
285 res = 0;
286 goto end;
287
288 exit_free:
289 kfree(resource->domain_devices);
290 end:
291 kfree(buffer.pointer);
292 return res;
293 }
294
set_trip(struct acpi_power_meter_resource * resource,u16 trip_idx,unsigned long trip)295 static int set_trip(struct acpi_power_meter_resource *resource, u16 trip_idx,
296 unsigned long trip)
297 {
298 unsigned long trip_bk;
299 int ret;
300
301 trip = DIV_ROUND_CLOSEST(trip, 1000);
302 trip_bk = resource->trip[trip_idx];
303
304 resource->trip[trip_idx] = trip;
305 ret = set_acpi_trip(resource);
306 if (ret) {
307 dev_err(&resource->acpi_dev->dev, "set %s failed.\n",
308 (trip_idx == POWER_METER_TRIP_AVERAGE_MIN_IDX) ?
309 "power1_average_min" : "power1_average_max");
310 resource->trip[trip_idx] = trip_bk;
311 }
312
313 return ret;
314 }
315
set_cap(struct acpi_power_meter_resource * resource,unsigned long cap)316 static int set_cap(struct acpi_power_meter_resource *resource,
317 unsigned long cap)
318 {
319 union acpi_object arg0 = { ACPI_TYPE_INTEGER };
320 struct acpi_object_list args = { 1, &arg0 };
321 unsigned long long data;
322 acpi_status status;
323
324 cap = DIV_ROUND_CLOSEST(cap, 1000);
325 if (cap > resource->caps.max_cap || cap < resource->caps.min_cap)
326 return -EINVAL;
327
328 arg0.integer.value = cap;
329 status = acpi_evaluate_integer(resource->acpi_dev->handle, "_SHL",
330 &args, &data);
331 if (ACPI_FAILURE(status)) {
332 acpi_evaluation_failure_warn(resource->acpi_dev->handle, "_SHL",
333 status);
334 return -EINVAL;
335 }
336 resource->cap = cap;
337
338 /* _SHL returns 0 on success, nonzero otherwise */
339 if (data)
340 return -EINVAL;
341
342 return 0;
343 }
344
set_avg_interval(struct acpi_power_meter_resource * resource,unsigned long val)345 static int set_avg_interval(struct acpi_power_meter_resource *resource,
346 unsigned long val)
347 {
348 union acpi_object arg0 = { ACPI_TYPE_INTEGER };
349 struct acpi_object_list args = { 1, &arg0 };
350 unsigned long long data;
351 acpi_status status;
352
353 if (val > resource->caps.max_avg_interval ||
354 val < resource->caps.min_avg_interval)
355 return -EINVAL;
356
357 arg0.integer.value = val;
358 status = acpi_evaluate_integer(resource->acpi_dev->handle, "_PAI",
359 &args, &data);
360 if (ACPI_FAILURE(status)) {
361 acpi_evaluation_failure_warn(resource->acpi_dev->handle, "_PAI",
362 status);
363 return -EINVAL;
364 }
365 resource->avg_interval = val;
366
367 /* _PAI returns 0 on success, nonzero otherwise */
368 if (data)
369 return -EINVAL;
370
371 return 0;
372 }
373
get_power_alarm_state(struct acpi_power_meter_resource * resource,long * val)374 static int get_power_alarm_state(struct acpi_power_meter_resource *resource,
375 long *val)
376 {
377 int ret;
378
379 ret = update_meter(resource);
380 if (ret)
381 return ret;
382
383 /* need to update cap if not to support the notification. */
384 if (!(resource->caps.flags & POWER_METER_CAN_NOTIFY)) {
385 ret = update_cap(resource);
386 if (ret)
387 return ret;
388 resource->power_alarm = resource->power > resource->cap;
389 *val = resource->power_alarm;
390 } else {
391 *val = resource->power_alarm || resource->power > resource->cap;
392 resource->power_alarm = resource->power > resource->cap;
393 }
394
395 return 0;
396 }
397
power_meter_is_visible(const void * data,enum hwmon_sensor_types type,u32 attr,int channel)398 static umode_t power_meter_is_visible(const void *data,
399 enum hwmon_sensor_types type,
400 u32 attr, int channel)
401 {
402 const struct acpi_power_meter_resource *res = data;
403
404 if (type != hwmon_power)
405 return 0;
406
407 switch (attr) {
408 case hwmon_power_average:
409 case hwmon_power_average_interval_min:
410 case hwmon_power_average_interval_max:
411 if (res->caps.flags & POWER_METER_CAN_MEASURE)
412 return 0444;
413 break;
414 case hwmon_power_average_interval:
415 if (res->caps.flags & POWER_METER_CAN_MEASURE)
416 return 0644;
417 break;
418 case hwmon_power_cap_min:
419 case hwmon_power_cap_max:
420 case hwmon_power_alarm:
421 if (res->caps.flags & POWER_METER_CAN_CAP && can_cap_in_hardware())
422 return 0444;
423 break;
424 case hwmon_power_cap:
425 if (res->caps.flags & POWER_METER_CAN_CAP && can_cap_in_hardware()) {
426 if (res->caps.configurable_cap)
427 return 0644;
428 else
429 return 0444;
430 }
431 break;
432 default:
433 break;
434 }
435
436 return 0;
437 }
438
power_meter_read(struct device * dev,enum hwmon_sensor_types type,u32 attr,int channel,long * val)439 static int power_meter_read(struct device *dev, enum hwmon_sensor_types type,
440 u32 attr, int channel, long *val)
441 {
442 struct acpi_power_meter_resource *res = dev_get_drvdata(dev);
443 int ret = 0;
444
445 if (type != hwmon_power)
446 return -EINVAL;
447
448 guard(mutex)(&res->lock);
449
450 switch (attr) {
451 case hwmon_power_average:
452 ret = update_meter(res);
453 if (ret)
454 return ret;
455 if (res->power == UNKNOWN_POWER)
456 return -ENODATA;
457 *val = res->power * 1000;
458 break;
459 case hwmon_power_average_interval_min:
460 *val = res->caps.min_avg_interval;
461 break;
462 case hwmon_power_average_interval_max:
463 *val = res->caps.max_avg_interval;
464 break;
465 case hwmon_power_average_interval:
466 ret = update_avg_interval(res);
467 if (ret)
468 return ret;
469 *val = (res)->avg_interval;
470 break;
471 case hwmon_power_cap_min:
472 *val = res->caps.min_cap * 1000;
473 break;
474 case hwmon_power_cap_max:
475 *val = res->caps.max_cap * 1000;
476 break;
477 case hwmon_power_alarm:
478 ret = get_power_alarm_state(res, val);
479 if (ret)
480 return ret;
481 break;
482 case hwmon_power_cap:
483 ret = update_cap(res);
484 if (ret)
485 return ret;
486 *val = res->cap * 1000;
487 break;
488 default:
489 break;
490 }
491
492 return 0;
493 }
494
power_meter_write(struct device * dev,enum hwmon_sensor_types type,u32 attr,int channel,long val)495 static int power_meter_write(struct device *dev, enum hwmon_sensor_types type,
496 u32 attr, int channel, long val)
497 {
498 struct acpi_power_meter_resource *res = dev_get_drvdata(dev);
499 int ret;
500
501 if (type != hwmon_power)
502 return -EINVAL;
503
504 guard(mutex)(&res->lock);
505 switch (attr) {
506 case hwmon_power_cap:
507 ret = set_cap(res, val);
508 break;
509 case hwmon_power_average_interval:
510 ret = set_avg_interval(res, val);
511 break;
512 default:
513 ret = -EOPNOTSUPP;
514 }
515
516 return ret;
517 }
518
519 static const struct hwmon_channel_info * const power_meter_info[] = {
520 HWMON_CHANNEL_INFO(power, HWMON_P_AVERAGE |
521 HWMON_P_AVERAGE_INTERVAL | HWMON_P_AVERAGE_INTERVAL_MIN |
522 HWMON_P_AVERAGE_INTERVAL_MAX | HWMON_P_CAP | HWMON_P_CAP_MIN |
523 HWMON_P_CAP_MAX | HWMON_P_ALARM),
524 NULL
525 };
526
527 static const struct hwmon_ops power_meter_ops = {
528 .is_visible = power_meter_is_visible,
529 .read = power_meter_read,
530 .write = power_meter_write,
531 };
532
533 static const struct hwmon_chip_info power_meter_chip_info = {
534 .ops = &power_meter_ops,
535 .info = power_meter_info,
536 };
537
power1_average_max_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)538 static ssize_t power1_average_max_store(struct device *dev,
539 struct device_attribute *attr,
540 const char *buf, size_t count)
541 {
542 struct acpi_power_meter_resource *res = dev_get_drvdata(dev);
543 unsigned long trip;
544 int ret;
545
546 ret = kstrtoul(buf, 10, &trip);
547 if (ret)
548 return ret;
549
550 mutex_lock(&res->lock);
551 ret = set_trip(res, POWER_METER_TRIP_AVERAGE_MAX_IDX, trip);
552 mutex_unlock(&res->lock);
553
554 return ret == 0 ? count : ret;
555 }
556
power1_average_min_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)557 static ssize_t power1_average_min_store(struct device *dev,
558 struct device_attribute *attr,
559 const char *buf, size_t count)
560 {
561 struct acpi_power_meter_resource *res = dev_get_drvdata(dev);
562 unsigned long trip;
563 int ret;
564
565 ret = kstrtoul(buf, 10, &trip);
566 if (ret)
567 return ret;
568
569 mutex_lock(&res->lock);
570 ret = set_trip(res, POWER_METER_TRIP_AVERAGE_MIN_IDX, trip);
571 mutex_unlock(&res->lock);
572
573 return ret == 0 ? count : ret;
574 }
575
power1_average_min_show(struct device * dev,struct device_attribute * attr,char * buf)576 static ssize_t power1_average_min_show(struct device *dev,
577 struct device_attribute *attr, char *buf)
578 {
579 struct acpi_power_meter_resource *res = dev_get_drvdata(dev);
580
581 if (res->trip[POWER_METER_TRIP_AVERAGE_MIN_IDX] < 0)
582 return sysfs_emit(buf, "unknown\n");
583
584 return sysfs_emit(buf, "%lld\n",
585 res->trip[POWER_METER_TRIP_AVERAGE_MIN_IDX] * 1000);
586 }
587
power1_average_max_show(struct device * dev,struct device_attribute * attr,char * buf)588 static ssize_t power1_average_max_show(struct device *dev,
589 struct device_attribute *attr, char *buf)
590 {
591 struct acpi_power_meter_resource *res = dev_get_drvdata(dev);
592
593 if (res->trip[POWER_METER_TRIP_AVERAGE_MAX_IDX] < 0)
594 return sysfs_emit(buf, "unknown\n");
595
596 return sysfs_emit(buf, "%lld\n",
597 res->trip[POWER_METER_TRIP_AVERAGE_MAX_IDX] * 1000);
598 }
599
power1_cap_hyst_show(struct device * dev,struct device_attribute * attr,char * buf)600 static ssize_t power1_cap_hyst_show(struct device *dev,
601 struct device_attribute *attr, char *buf)
602 {
603 struct acpi_power_meter_resource *res = dev_get_drvdata(dev);
604
605 if (res->caps.hysteresis == UNKNOWN_HYSTERESIS)
606 return sysfs_emit(buf, "unknown\n");
607
608 return sysfs_emit(buf, "%llu\n", res->caps.hysteresis * 1000);
609 }
610
power1_accuracy_show(struct device * dev,struct device_attribute * attr,char * buf)611 static ssize_t power1_accuracy_show(struct device *dev,
612 struct device_attribute *attr,
613 char *buf)
614 {
615 struct acpi_power_meter_resource *res = dev_get_drvdata(dev);
616 unsigned int acc = res->caps.accuracy;
617
618 return sysfs_emit(buf, "%u.%u%%\n", acc / 1000, acc % 1000);
619 }
620
power1_is_battery_show(struct device * dev,struct device_attribute * attr,char * buf)621 static ssize_t power1_is_battery_show(struct device *dev,
622 struct device_attribute *attr,
623 char *buf)
624 {
625 struct acpi_power_meter_resource *res = dev_get_drvdata(dev);
626
627 return sysfs_emit(buf, "%u\n",
628 res->caps.flags & POWER_METER_IS_BATTERY ? 1 : 0);
629 }
630
power1_model_number_show(struct device * dev,struct device_attribute * attr,char * buf)631 static ssize_t power1_model_number_show(struct device *dev,
632 struct device_attribute *attr,
633 char *buf)
634 {
635 struct acpi_power_meter_resource *res = dev_get_drvdata(dev);
636
637 return sysfs_emit(buf, "%s\n", res->model_number);
638 }
639
power1_oem_info_show(struct device * dev,struct device_attribute * attr,char * buf)640 static ssize_t power1_oem_info_show(struct device *dev,
641 struct device_attribute *attr,
642 char *buf)
643 {
644 struct acpi_power_meter_resource *res = dev_get_drvdata(dev);
645
646 return sysfs_emit(buf, "%s\n", res->oem_info);
647 }
648
power1_serial_number_show(struct device * dev,struct device_attribute * attr,char * buf)649 static ssize_t power1_serial_number_show(struct device *dev,
650 struct device_attribute *attr,
651 char *buf)
652 {
653 struct acpi_power_meter_resource *res = dev_get_drvdata(dev);
654
655 return sysfs_emit(buf, "%s\n", res->serial_number);
656 }
657
658 /* depend on POWER_METER_CAN_TRIP */
659 static DEVICE_ATTR_RW(power1_average_max);
660 static DEVICE_ATTR_RW(power1_average_min);
661
662 /* depend on POWER_METER_CAN_CAP */
663 static DEVICE_ATTR_RO(power1_cap_hyst);
664
665 /* depend on POWER_METER_CAN_MEASURE */
666 static DEVICE_ATTR_RO(power1_accuracy);
667 static DEVICE_ATTR_RO(power1_is_battery);
668
669 static DEVICE_ATTR_RO(power1_model_number);
670 static DEVICE_ATTR_RO(power1_oem_info);
671 static DEVICE_ATTR_RO(power1_serial_number);
672
power_extra_is_visible(struct kobject * kobj,struct attribute * attr,int idx)673 static umode_t power_extra_is_visible(struct kobject *kobj,
674 struct attribute *attr, int idx)
675 {
676 struct device *dev = kobj_to_dev(kobj);
677 struct acpi_power_meter_resource *res = dev_get_drvdata(dev);
678
679 if (attr == &dev_attr_power1_is_battery.attr ||
680 attr == &dev_attr_power1_accuracy.attr) {
681 if ((res->caps.flags & POWER_METER_CAN_MEASURE) == 0)
682 return 0;
683 }
684
685 if (attr == &dev_attr_power1_cap_hyst.attr) {
686 if ((res->caps.flags & POWER_METER_CAN_CAP) == 0) {
687 return 0;
688 } else if (!can_cap_in_hardware()) {
689 dev_warn(&res->acpi_dev->dev,
690 "Ignoring unsafe software power cap!\n");
691 return 0;
692 }
693 }
694
695 if (attr == &dev_attr_power1_average_max.attr ||
696 attr == &dev_attr_power1_average_min.attr) {
697 if ((res->caps.flags & POWER_METER_CAN_TRIP) == 0)
698 return 0;
699 }
700
701 return attr->mode;
702 }
703
704 static struct attribute *power_extra_attrs[] = {
705 &dev_attr_power1_average_max.attr,
706 &dev_attr_power1_average_min.attr,
707 &dev_attr_power1_cap_hyst.attr,
708 &dev_attr_power1_accuracy.attr,
709 &dev_attr_power1_is_battery.attr,
710 &dev_attr_power1_model_number.attr,
711 &dev_attr_power1_oem_info.attr,
712 &dev_attr_power1_serial_number.attr,
713 NULL
714 };
715
716 static const struct attribute_group power_extra_group = {
717 .attrs = power_extra_attrs,
718 .is_visible = power_extra_is_visible,
719 };
720
721 __ATTRIBUTE_GROUPS(power_extra);
722
free_capabilities(struct acpi_power_meter_resource * resource)723 static void free_capabilities(struct acpi_power_meter_resource *resource)
724 {
725 acpi_string *str;
726 int i;
727
728 str = &resource->model_number;
729 for (i = 0; i < 3; i++, str++) {
730 kfree(*str);
731 *str = NULL;
732 }
733 }
734
read_capabilities(struct acpi_power_meter_resource * resource)735 static int read_capabilities(struct acpi_power_meter_resource *resource)
736 {
737 int res = 0;
738 int i;
739 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
740 struct acpi_buffer state = { 0, NULL };
741 struct acpi_buffer format = { sizeof("NNNNNNNNNNN"), "NNNNNNNNNNN" };
742 union acpi_object *pss;
743 acpi_string *str;
744 acpi_status status;
745
746 status = acpi_evaluate_object(resource->acpi_dev->handle, "_PMC", NULL,
747 &buffer);
748 if (ACPI_FAILURE(status)) {
749 acpi_evaluation_failure_warn(resource->acpi_dev->handle, "_PMC",
750 status);
751 return -ENODEV;
752 }
753
754 pss = buffer.pointer;
755 if (!pss ||
756 pss->type != ACPI_TYPE_PACKAGE ||
757 pss->package.count != 14) {
758 dev_err(&resource->acpi_dev->dev, ACPI_POWER_METER_NAME
759 "Invalid _PMC data\n");
760 res = -EFAULT;
761 goto end;
762 }
763
764 /* Grab all the integer data at once */
765 state.length = sizeof(struct acpi_power_meter_capabilities);
766 state.pointer = &resource->caps;
767
768 status = acpi_extract_package(pss, &format, &state);
769 if (ACPI_FAILURE(status)) {
770 dev_err(&resource->acpi_dev->dev, ACPI_POWER_METER_NAME
771 "_PMC package parsing failed: %s\n",
772 acpi_format_exception(status));
773 res = -EFAULT;
774 goto end;
775 }
776
777 if (resource->caps.units) {
778 dev_err(&resource->acpi_dev->dev, ACPI_POWER_METER_NAME
779 "Unknown units %llu.\n",
780 resource->caps.units);
781 res = -EINVAL;
782 goto end;
783 }
784
785 /* Grab the string data */
786 str = &resource->model_number;
787
788 for (i = 11; i < 14; i++) {
789 union acpi_object *element = &pss->package.elements[i];
790
791 if (element->type != ACPI_TYPE_STRING) {
792 res = -EINVAL;
793 goto error;
794 }
795
796 *str = kmemdup_nul(element->string.pointer, element->string.length,
797 GFP_KERNEL);
798 if (!*str) {
799 res = -ENOMEM;
800 goto error;
801 }
802
803 str++;
804 }
805
806 dev_info(&resource->acpi_dev->dev, "Found ACPI power meter.\n");
807 goto end;
808 error:
809 free_capabilities(resource);
810 end:
811 kfree(buffer.pointer);
812 return res;
813 }
814
815 /* Handle ACPI event notifications */
acpi_power_meter_notify(struct acpi_device * device,u32 event)816 static void acpi_power_meter_notify(struct acpi_device *device, u32 event)
817 {
818 struct acpi_power_meter_resource *resource;
819 int res;
820
821 if (!device || !acpi_driver_data(device))
822 return;
823
824 resource = acpi_driver_data(device);
825
826 switch (event) {
827 case METER_NOTIFY_CONFIG:
828 mutex_lock(&resource->lock);
829 free_capabilities(resource);
830 remove_domain_devices(resource);
831 hwmon_device_unregister(resource->hwmon_dev);
832 res = read_capabilities(resource);
833 if (res)
834 dev_err_once(&device->dev, "read capabilities failed.\n");
835 res = read_domain_devices(resource);
836 if (res && res != -ENODEV)
837 dev_err_once(&device->dev, "read domain devices failed.\n");
838 resource->hwmon_dev =
839 hwmon_device_register_with_info(&device->dev,
840 ACPI_POWER_METER_NAME,
841 resource,
842 &power_meter_chip_info,
843 power_extra_groups);
844 if (IS_ERR(resource->hwmon_dev))
845 dev_err_once(&device->dev, "register hwmon device failed.\n");
846 mutex_unlock(&resource->lock);
847 break;
848 case METER_NOTIFY_TRIP:
849 sysfs_notify(&device->dev.kobj, NULL, POWER_AVERAGE_NAME);
850 break;
851 case METER_NOTIFY_CAP:
852 mutex_lock(&resource->lock);
853 res = update_cap(resource);
854 if (res)
855 dev_err_once(&device->dev, "update cap failed when capping value is changed.\n");
856 mutex_unlock(&resource->lock);
857 sysfs_notify(&device->dev.kobj, NULL, POWER_CAP_NAME);
858 break;
859 case METER_NOTIFY_INTERVAL:
860 sysfs_notify(&device->dev.kobj, NULL, POWER_AVG_INTERVAL_NAME);
861 break;
862 case METER_NOTIFY_CAPPING:
863 mutex_lock(&resource->lock);
864 resource->power_alarm = true;
865 mutex_unlock(&resource->lock);
866 sysfs_notify(&device->dev.kobj, NULL, POWER_ALARM_NAME);
867 dev_info(&device->dev, "Capping in progress.\n");
868 break;
869 default:
870 WARN(1, "Unexpected event %d\n", event);
871 break;
872 }
873
874 acpi_bus_generate_netlink_event(ACPI_POWER_METER_CLASS,
875 dev_name(&device->dev), event, 0);
876 }
877
acpi_power_meter_add(struct acpi_device * device)878 static int acpi_power_meter_add(struct acpi_device *device)
879 {
880 int res;
881 struct acpi_power_meter_resource *resource;
882
883 if (!device)
884 return -EINVAL;
885
886 resource = kzalloc(sizeof(*resource), GFP_KERNEL);
887 if (!resource)
888 return -ENOMEM;
889
890 resource->sensors_valid = 0;
891 resource->acpi_dev = device;
892 mutex_init(&resource->lock);
893 strcpy(acpi_device_name(device), ACPI_POWER_METER_DEVICE_NAME);
894 strcpy(acpi_device_class(device), ACPI_POWER_METER_CLASS);
895 device->driver_data = resource;
896
897 #if IS_REACHABLE(CONFIG_ACPI_IPMI)
898 /*
899 * On Dell systems several methods of acpi_power_meter access
900 * variables in IPMI region, so wait until IPMI space handler is
901 * installed by acpi_ipmi and also wait until SMI is selected to make
902 * the space handler fully functional.
903 */
904 if (dmi_match(DMI_SYS_VENDOR, "Dell Inc.")) {
905 struct acpi_device *ipi_device = acpi_dev_get_first_match_dev("IPI0001", NULL, -1);
906
907 if (ipi_device && acpi_wait_for_acpi_ipmi())
908 dev_warn(&device->dev, "Waiting for ACPI IPMI timeout");
909 acpi_dev_put(ipi_device);
910 }
911 #endif
912
913 res = read_capabilities(resource);
914 if (res)
915 goto exit_free;
916
917 resource->trip[0] = -1;
918 resource->trip[1] = -1;
919
920 /* _PMD method is optional. */
921 res = read_domain_devices(resource);
922 if (res && res != -ENODEV)
923 goto exit_free_capability;
924
925 resource->hwmon_dev =
926 hwmon_device_register_with_info(&device->dev,
927 ACPI_POWER_METER_NAME, resource,
928 &power_meter_chip_info,
929 power_extra_groups);
930 if (IS_ERR(resource->hwmon_dev)) {
931 res = PTR_ERR(resource->hwmon_dev);
932 goto exit_remove;
933 }
934
935 res = 0;
936 goto exit;
937
938 exit_remove:
939 remove_domain_devices(resource);
940 exit_free_capability:
941 free_capabilities(resource);
942 exit_free:
943 kfree(resource);
944 exit:
945 return res;
946 }
947
acpi_power_meter_remove(struct acpi_device * device)948 static void acpi_power_meter_remove(struct acpi_device *device)
949 {
950 struct acpi_power_meter_resource *resource;
951
952 if (!device || !acpi_driver_data(device))
953 return;
954
955 resource = acpi_driver_data(device);
956 hwmon_device_unregister(resource->hwmon_dev);
957
958 remove_domain_devices(resource);
959 free_capabilities(resource);
960
961 kfree(resource);
962 }
963
acpi_power_meter_resume(struct device * dev)964 static int acpi_power_meter_resume(struct device *dev)
965 {
966 struct acpi_power_meter_resource *resource;
967
968 if (!dev)
969 return -EINVAL;
970
971 resource = acpi_driver_data(to_acpi_device(dev));
972 if (!resource)
973 return -EINVAL;
974
975 free_capabilities(resource);
976 read_capabilities(resource);
977
978 return 0;
979 }
980
981 static DEFINE_SIMPLE_DEV_PM_OPS(acpi_power_meter_pm, NULL,
982 acpi_power_meter_resume);
983
984 static struct acpi_driver acpi_power_meter_driver = {
985 .name = "power_meter",
986 .class = ACPI_POWER_METER_CLASS,
987 .ids = power_meter_ids,
988 .ops = {
989 .add = acpi_power_meter_add,
990 .remove = acpi_power_meter_remove,
991 .notify = acpi_power_meter_notify,
992 },
993 .drv.pm = pm_sleep_ptr(&acpi_power_meter_pm),
994 };
995
996 /* Module init/exit routines */
enable_cap_knobs(const struct dmi_system_id * d)997 static int __init enable_cap_knobs(const struct dmi_system_id *d)
998 {
999 cap_in_hardware = 1;
1000 return 0;
1001 }
1002
1003 static const struct dmi_system_id pm_dmi_table[] __initconst = {
1004 {
1005 enable_cap_knobs, "IBM Active Energy Manager",
1006 {
1007 DMI_MATCH(DMI_SYS_VENDOR, "IBM")
1008 },
1009 },
1010 {}
1011 };
1012
acpi_power_meter_init(void)1013 static int __init acpi_power_meter_init(void)
1014 {
1015 int result;
1016
1017 if (acpi_disabled)
1018 return -ENODEV;
1019
1020 dmi_check_system(pm_dmi_table);
1021
1022 result = acpi_bus_register_driver(&acpi_power_meter_driver);
1023 if (result < 0)
1024 return result;
1025
1026 return 0;
1027 }
1028
acpi_power_meter_exit(void)1029 static void __exit acpi_power_meter_exit(void)
1030 {
1031 acpi_bus_unregister_driver(&acpi_power_meter_driver);
1032 }
1033
1034 MODULE_AUTHOR("Darrick J. Wong <[email protected]>");
1035 MODULE_DESCRIPTION("ACPI 4.0 power meter driver");
1036 MODULE_LICENSE("GPL");
1037
1038 module_param(force_cap_on, bool, 0644);
1039 MODULE_PARM_DESC(force_cap_on, "Enable power cap even it is unsafe to do so.");
1040
1041 module_init(acpi_power_meter_init);
1042 module_exit(acpi_power_meter_exit);
1043