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 <darrick.wong@oracle.com>
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
50 static DEFINE_MUTEX(acpi_notify_lock);
51
can_cap_in_hardware(void)52 static int can_cap_in_hardware(void)
53 {
54 return force_cap_on || cap_in_hardware;
55 }
56
57 static const struct acpi_device_id power_meter_ids[] = {
58 {"ACPI000D", 0},
59 {"", 0},
60 };
61 MODULE_DEVICE_TABLE(acpi, power_meter_ids);
62
63 struct acpi_power_meter_capabilities {
64 u64 flags;
65 u64 units;
66 u64 type;
67 u64 accuracy;
68 u64 sampling_time;
69 u64 min_avg_interval;
70 u64 max_avg_interval;
71 u64 hysteresis;
72 u64 configurable_cap;
73 u64 min_cap;
74 u64 max_cap;
75 };
76
77 struct acpi_power_meter_resource {
78 struct acpi_device *acpi_dev;
79 acpi_bus_id name;
80 struct mutex lock;
81 struct device *hwmon_dev;
82 struct acpi_power_meter_capabilities caps;
83 acpi_string model_number;
84 acpi_string serial_number;
85 acpi_string oem_info;
86 u64 power;
87 u64 cap;
88 u64 avg_interval;
89 bool power_alarm;
90 int sensors_valid;
91 unsigned long sensors_last_updated;
92 #define POWER_METER_TRIP_AVERAGE_MIN_IDX 0
93 #define POWER_METER_TRIP_AVERAGE_MAX_IDX 1
94 s64 trip[2];
95 int num_domain_devices;
96 struct acpi_device **domain_devices;
97 struct kobject *holders_dir;
98 };
99
100 /* Averaging interval */
update_avg_interval(struct acpi_power_meter_resource * resource)101 static int update_avg_interval(struct acpi_power_meter_resource *resource)
102 {
103 unsigned long long data;
104 acpi_status status;
105
106 status = acpi_evaluate_integer(resource->acpi_dev->handle, "_GAI",
107 NULL, &data);
108 if (ACPI_FAILURE(status)) {
109 acpi_evaluation_failure_warn(resource->acpi_dev->handle, "_GAI",
110 status);
111 return -ENODEV;
112 }
113
114 resource->avg_interval = data;
115 return 0;
116 }
117
118 /* Cap functions */
update_cap(struct acpi_power_meter_resource * resource)119 static int update_cap(struct acpi_power_meter_resource *resource)
120 {
121 unsigned long long data;
122 acpi_status status;
123
124 status = acpi_evaluate_integer(resource->acpi_dev->handle, "_GHL",
125 NULL, &data);
126 if (ACPI_FAILURE(status)) {
127 acpi_evaluation_failure_warn(resource->acpi_dev->handle, "_GHL",
128 status);
129 return -ENODEV;
130 }
131
132 resource->cap = data;
133 return 0;
134 }
135
136 /* Power meter trip points */
set_acpi_trip(struct acpi_power_meter_resource * resource)137 static int set_acpi_trip(struct acpi_power_meter_resource *resource)
138 {
139 union acpi_object arg_objs[] = {
140 {ACPI_TYPE_INTEGER},
141 {ACPI_TYPE_INTEGER}
142 };
143 struct acpi_object_list args = { 2, arg_objs };
144 unsigned long long data;
145 acpi_status status;
146
147 /* Both trip levels must be set */
148 if (resource->trip[0] < 0 || resource->trip[1] < 0)
149 return 0;
150
151 /* This driver stores min, max; ACPI wants max, min. */
152 arg_objs[0].integer.value = resource->trip[1];
153 arg_objs[1].integer.value = resource->trip[0];
154
155 status = acpi_evaluate_integer(resource->acpi_dev->handle, "_PTP",
156 &args, &data);
157 if (ACPI_FAILURE(status)) {
158 acpi_evaluation_failure_warn(resource->acpi_dev->handle, "_PTP",
159 status);
160 return -EINVAL;
161 }
162
163 /* _PTP returns 0 on success, nonzero otherwise */
164 if (data)
165 return -EINVAL;
166
167 return 0;
168 }
169
170 /* Power meter */
update_meter(struct acpi_power_meter_resource * resource)171 static int update_meter(struct acpi_power_meter_resource *resource)
172 {
173 unsigned long long data;
174 acpi_status status;
175 unsigned long local_jiffies = jiffies;
176
177 if (time_before(local_jiffies, resource->sensors_last_updated +
178 msecs_to_jiffies(resource->caps.sampling_time)) &&
179 resource->sensors_valid)
180 return 0;
181
182 status = acpi_evaluate_integer(resource->acpi_dev->handle, "_PMM",
183 NULL, &data);
184 if (ACPI_FAILURE(status)) {
185 acpi_evaluation_failure_warn(resource->acpi_dev->handle, "_PMM",
186 status);
187 return -ENODEV;
188 }
189
190 resource->power = data;
191 resource->sensors_valid = 1;
192 resource->sensors_last_updated = jiffies;
193 return 0;
194 }
195
196 /* Read power domain data */
remove_domain_devices(struct acpi_power_meter_resource * resource)197 static void remove_domain_devices(struct acpi_power_meter_resource *resource)
198 {
199 int i;
200
201 if (!resource->num_domain_devices)
202 return;
203
204 for (i = 0; i < resource->num_domain_devices; i++) {
205 struct acpi_device *obj = resource->domain_devices[i];
206
207 if (!obj)
208 continue;
209
210 sysfs_remove_link(resource->holders_dir,
211 kobject_name(&obj->dev.kobj));
212 acpi_dev_put(obj);
213 }
214
215 kfree(resource->domain_devices);
216 kobject_put(resource->holders_dir);
217 resource->num_domain_devices = 0;
218 }
219
read_domain_devices(struct acpi_power_meter_resource * resource)220 static int read_domain_devices(struct acpi_power_meter_resource *resource)
221 {
222 int res = 0;
223 int i;
224 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
225 union acpi_object *pss;
226 acpi_status status;
227
228 status = acpi_evaluate_object(resource->acpi_dev->handle, "_PMD", NULL,
229 &buffer);
230 if (ACPI_FAILURE(status)) {
231 acpi_evaluation_failure_warn(resource->acpi_dev->handle, "_PMD",
232 status);
233 return -ENODEV;
234 }
235
236 pss = buffer.pointer;
237 if (!pss ||
238 pss->type != ACPI_TYPE_PACKAGE) {
239 dev_err(&resource->acpi_dev->dev, ACPI_POWER_METER_NAME
240 "Invalid _PMD data\n");
241 res = -EFAULT;
242 goto end;
243 }
244
245 if (!pss->package.count)
246 goto end;
247
248 resource->domain_devices = kcalloc(pss->package.count,
249 sizeof(struct acpi_device *),
250 GFP_KERNEL);
251 if (!resource->domain_devices) {
252 res = -ENOMEM;
253 goto end;
254 }
255
256 resource->holders_dir = kobject_create_and_add("measures",
257 &resource->acpi_dev->dev.kobj);
258 if (!resource->holders_dir) {
259 res = -ENOMEM;
260 goto exit_free;
261 }
262
263 resource->num_domain_devices = pss->package.count;
264
265 for (i = 0; i < pss->package.count; i++) {
266 struct acpi_device *obj;
267 union acpi_object *element = &pss->package.elements[i];
268
269 /* Refuse non-references */
270 if (element->type != ACPI_TYPE_LOCAL_REFERENCE)
271 continue;
272
273 /* Create a symlink to domain objects */
274 obj = acpi_get_acpi_dev(element->reference.handle);
275 resource->domain_devices[i] = obj;
276 if (!obj)
277 continue;
278
279 res = sysfs_create_link(resource->holders_dir, &obj->dev.kobj,
280 kobject_name(&obj->dev.kobj));
281 if (res) {
282 acpi_dev_put(obj);
283 resource->domain_devices[i] = NULL;
284 }
285 }
286
287 res = 0;
288 goto end;
289
290 exit_free:
291 kfree(resource->domain_devices);
292 end:
293 kfree(buffer.pointer);
294 return res;
295 }
296
set_trip(struct acpi_power_meter_resource * resource,u16 trip_idx,unsigned long trip)297 static int set_trip(struct acpi_power_meter_resource *resource, u16 trip_idx,
298 unsigned long trip)
299 {
300 unsigned long trip_bk;
301 int ret;
302
303 trip = DIV_ROUND_CLOSEST(trip, 1000);
304 trip_bk = resource->trip[trip_idx];
305
306 resource->trip[trip_idx] = trip;
307 ret = set_acpi_trip(resource);
308 if (ret) {
309 dev_err(&resource->acpi_dev->dev, "set %s failed.\n",
310 (trip_idx == POWER_METER_TRIP_AVERAGE_MIN_IDX) ?
311 "power1_average_min" : "power1_average_max");
312 resource->trip[trip_idx] = trip_bk;
313 }
314
315 return ret;
316 }
317
set_cap(struct acpi_power_meter_resource * resource,unsigned long cap)318 static int set_cap(struct acpi_power_meter_resource *resource,
319 unsigned long cap)
320 {
321 union acpi_object arg0 = { ACPI_TYPE_INTEGER };
322 struct acpi_object_list args = { 1, &arg0 };
323 unsigned long long data;
324 acpi_status status;
325
326 cap = DIV_ROUND_CLOSEST(cap, 1000);
327 if (cap > resource->caps.max_cap || cap < resource->caps.min_cap)
328 return -EINVAL;
329
330 arg0.integer.value = cap;
331 status = acpi_evaluate_integer(resource->acpi_dev->handle, "_SHL",
332 &args, &data);
333 if (ACPI_FAILURE(status)) {
334 acpi_evaluation_failure_warn(resource->acpi_dev->handle, "_SHL",
335 status);
336 return -EINVAL;
337 }
338 resource->cap = cap;
339
340 /* _SHL returns 0 on success, nonzero otherwise */
341 if (data)
342 return -EINVAL;
343
344 return 0;
345 }
346
set_avg_interval(struct acpi_power_meter_resource * resource,unsigned long val)347 static int set_avg_interval(struct acpi_power_meter_resource *resource,
348 unsigned long val)
349 {
350 union acpi_object arg0 = { ACPI_TYPE_INTEGER };
351 struct acpi_object_list args = { 1, &arg0 };
352 unsigned long long data;
353 acpi_status status;
354
355 if (val > resource->caps.max_avg_interval ||
356 val < resource->caps.min_avg_interval)
357 return -EINVAL;
358
359 arg0.integer.value = val;
360 status = acpi_evaluate_integer(resource->acpi_dev->handle, "_PAI",
361 &args, &data);
362 if (ACPI_FAILURE(status)) {
363 acpi_evaluation_failure_warn(resource->acpi_dev->handle, "_PAI",
364 status);
365 return -EINVAL;
366 }
367 resource->avg_interval = val;
368
369 /* _PAI returns 0 on success, nonzero otherwise */
370 if (data)
371 return -EINVAL;
372
373 return 0;
374 }
375
get_power_alarm_state(struct acpi_power_meter_resource * resource,long * val)376 static int get_power_alarm_state(struct acpi_power_meter_resource *resource,
377 long *val)
378 {
379 int ret;
380
381 ret = update_meter(resource);
382 if (ret)
383 return ret;
384
385 /* need to update cap if not to support the notification. */
386 if (!(resource->caps.flags & POWER_METER_CAN_NOTIFY)) {
387 ret = update_cap(resource);
388 if (ret)
389 return ret;
390 resource->power_alarm = resource->power > resource->cap;
391 *val = resource->power_alarm;
392 } else {
393 *val = resource->power_alarm || resource->power > resource->cap;
394 resource->power_alarm = resource->power > resource->cap;
395 }
396
397 return 0;
398 }
399
power_meter_is_visible(const void * data,enum hwmon_sensor_types type,u32 attr,int channel)400 static umode_t power_meter_is_visible(const void *data,
401 enum hwmon_sensor_types type,
402 u32 attr, int channel)
403 {
404 const struct acpi_power_meter_resource *res = data;
405
406 if (type != hwmon_power)
407 return 0;
408
409 switch (attr) {
410 case hwmon_power_average:
411 case hwmon_power_average_interval_min:
412 case hwmon_power_average_interval_max:
413 if (res->caps.flags & POWER_METER_CAN_MEASURE)
414 return 0444;
415 break;
416 case hwmon_power_average_interval:
417 if (res->caps.flags & POWER_METER_CAN_MEASURE)
418 return 0644;
419 break;
420 case hwmon_power_cap_min:
421 case hwmon_power_cap_max:
422 case hwmon_power_alarm:
423 if (res->caps.flags & POWER_METER_CAN_CAP && can_cap_in_hardware())
424 return 0444;
425 break;
426 case hwmon_power_cap:
427 if (res->caps.flags & POWER_METER_CAN_CAP && can_cap_in_hardware()) {
428 if (res->caps.configurable_cap)
429 return 0644;
430 else
431 return 0444;
432 }
433 break;
434 default:
435 break;
436 }
437
438 return 0;
439 }
440
power_meter_read(struct device * dev,enum hwmon_sensor_types type,u32 attr,int channel,long * val)441 static int power_meter_read(struct device *dev, enum hwmon_sensor_types type,
442 u32 attr, int channel, long *val)
443 {
444 struct acpi_power_meter_resource *res = dev_get_drvdata(dev);
445 int ret = 0;
446
447 if (type != hwmon_power)
448 return -EINVAL;
449
450 guard(mutex)(&res->lock);
451
452 switch (attr) {
453 case hwmon_power_average:
454 ret = update_meter(res);
455 if (ret)
456 return ret;
457 if (res->power == UNKNOWN_POWER)
458 return -ENODATA;
459 *val = res->power * 1000;
460 break;
461 case hwmon_power_average_interval_min:
462 *val = res->caps.min_avg_interval;
463 break;
464 case hwmon_power_average_interval_max:
465 *val = res->caps.max_avg_interval;
466 break;
467 case hwmon_power_average_interval:
468 ret = update_avg_interval(res);
469 if (ret)
470 return ret;
471 *val = (res)->avg_interval;
472 break;
473 case hwmon_power_cap_min:
474 *val = res->caps.min_cap * 1000;
475 break;
476 case hwmon_power_cap_max:
477 *val = res->caps.max_cap * 1000;
478 break;
479 case hwmon_power_alarm:
480 ret = get_power_alarm_state(res, val);
481 if (ret)
482 return ret;
483 break;
484 case hwmon_power_cap:
485 ret = update_cap(res);
486 if (ret)
487 return ret;
488 *val = res->cap * 1000;
489 break;
490 default:
491 break;
492 }
493
494 return 0;
495 }
496
power_meter_write(struct device * dev,enum hwmon_sensor_types type,u32 attr,int channel,long val)497 static int power_meter_write(struct device *dev, enum hwmon_sensor_types type,
498 u32 attr, int channel, long val)
499 {
500 struct acpi_power_meter_resource *res = dev_get_drvdata(dev);
501 int ret;
502
503 if (type != hwmon_power)
504 return -EINVAL;
505
506 guard(mutex)(&res->lock);
507 switch (attr) {
508 case hwmon_power_cap:
509 ret = set_cap(res, val);
510 break;
511 case hwmon_power_average_interval:
512 ret = set_avg_interval(res, val);
513 break;
514 default:
515 ret = -EOPNOTSUPP;
516 }
517
518 return ret;
519 }
520
521 static const struct hwmon_channel_info * const power_meter_info[] = {
522 HWMON_CHANNEL_INFO(power, HWMON_P_AVERAGE |
523 HWMON_P_AVERAGE_INTERVAL | HWMON_P_AVERAGE_INTERVAL_MIN |
524 HWMON_P_AVERAGE_INTERVAL_MAX | HWMON_P_CAP | HWMON_P_CAP_MIN |
525 HWMON_P_CAP_MAX | HWMON_P_ALARM),
526 NULL
527 };
528
529 static const struct hwmon_ops power_meter_ops = {
530 .is_visible = power_meter_is_visible,
531 .read = power_meter_read,
532 .write = power_meter_write,
533 };
534
535 static const struct hwmon_chip_info power_meter_chip_info = {
536 .ops = &power_meter_ops,
537 .info = power_meter_info,
538 };
539
power1_average_max_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)540 static ssize_t power1_average_max_store(struct device *dev,
541 struct device_attribute *attr,
542 const char *buf, size_t count)
543 {
544 struct acpi_power_meter_resource *res = dev_get_drvdata(dev);
545 unsigned long trip;
546 int ret;
547
548 ret = kstrtoul(buf, 10, &trip);
549 if (ret)
550 return ret;
551
552 mutex_lock(&res->lock);
553 ret = set_trip(res, POWER_METER_TRIP_AVERAGE_MAX_IDX, trip);
554 mutex_unlock(&res->lock);
555
556 return ret == 0 ? count : ret;
557 }
558
power1_average_min_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)559 static ssize_t power1_average_min_store(struct device *dev,
560 struct device_attribute *attr,
561 const char *buf, size_t count)
562 {
563 struct acpi_power_meter_resource *res = dev_get_drvdata(dev);
564 unsigned long trip;
565 int ret;
566
567 ret = kstrtoul(buf, 10, &trip);
568 if (ret)
569 return ret;
570
571 mutex_lock(&res->lock);
572 ret = set_trip(res, POWER_METER_TRIP_AVERAGE_MIN_IDX, trip);
573 mutex_unlock(&res->lock);
574
575 return ret == 0 ? count : ret;
576 }
577
power1_average_min_show(struct device * dev,struct device_attribute * attr,char * buf)578 static ssize_t power1_average_min_show(struct device *dev,
579 struct device_attribute *attr, char *buf)
580 {
581 struct acpi_power_meter_resource *res = dev_get_drvdata(dev);
582
583 if (res->trip[POWER_METER_TRIP_AVERAGE_MIN_IDX] < 0)
584 return sysfs_emit(buf, "unknown\n");
585
586 return sysfs_emit(buf, "%lld\n",
587 res->trip[POWER_METER_TRIP_AVERAGE_MIN_IDX] * 1000);
588 }
589
power1_average_max_show(struct device * dev,struct device_attribute * attr,char * buf)590 static ssize_t power1_average_max_show(struct device *dev,
591 struct device_attribute *attr, char *buf)
592 {
593 struct acpi_power_meter_resource *res = dev_get_drvdata(dev);
594
595 if (res->trip[POWER_METER_TRIP_AVERAGE_MAX_IDX] < 0)
596 return sysfs_emit(buf, "unknown\n");
597
598 return sysfs_emit(buf, "%lld\n",
599 res->trip[POWER_METER_TRIP_AVERAGE_MAX_IDX] * 1000);
600 }
601
power1_cap_hyst_show(struct device * dev,struct device_attribute * attr,char * buf)602 static ssize_t power1_cap_hyst_show(struct device *dev,
603 struct device_attribute *attr, char *buf)
604 {
605 struct acpi_power_meter_resource *res = dev_get_drvdata(dev);
606
607 if (res->caps.hysteresis == UNKNOWN_HYSTERESIS)
608 return sysfs_emit(buf, "unknown\n");
609
610 return sysfs_emit(buf, "%llu\n", res->caps.hysteresis * 1000);
611 }
612
power1_accuracy_show(struct device * dev,struct device_attribute * attr,char * buf)613 static ssize_t power1_accuracy_show(struct device *dev,
614 struct device_attribute *attr,
615 char *buf)
616 {
617 struct acpi_power_meter_resource *res = dev_get_drvdata(dev);
618 unsigned int acc = res->caps.accuracy;
619
620 return sysfs_emit(buf, "%u.%u%%\n", acc / 1000, acc % 1000);
621 }
622
power1_is_battery_show(struct device * dev,struct device_attribute * attr,char * buf)623 static ssize_t power1_is_battery_show(struct device *dev,
624 struct device_attribute *attr,
625 char *buf)
626 {
627 struct acpi_power_meter_resource *res = dev_get_drvdata(dev);
628
629 return sysfs_emit(buf, "%u\n",
630 res->caps.flags & POWER_METER_IS_BATTERY ? 1 : 0);
631 }
632
power1_model_number_show(struct device * dev,struct device_attribute * attr,char * buf)633 static ssize_t power1_model_number_show(struct device *dev,
634 struct device_attribute *attr,
635 char *buf)
636 {
637 struct acpi_power_meter_resource *res = dev_get_drvdata(dev);
638
639 return sysfs_emit(buf, "%s\n", res->model_number);
640 }
641
power1_oem_info_show(struct device * dev,struct device_attribute * attr,char * buf)642 static ssize_t power1_oem_info_show(struct device *dev,
643 struct device_attribute *attr,
644 char *buf)
645 {
646 struct acpi_power_meter_resource *res = dev_get_drvdata(dev);
647
648 return sysfs_emit(buf, "%s\n", res->oem_info);
649 }
650
power1_serial_number_show(struct device * dev,struct device_attribute * attr,char * buf)651 static ssize_t power1_serial_number_show(struct device *dev,
652 struct device_attribute *attr,
653 char *buf)
654 {
655 struct acpi_power_meter_resource *res = dev_get_drvdata(dev);
656
657 return sysfs_emit(buf, "%s\n", res->serial_number);
658 }
659
660 /* depend on POWER_METER_CAN_TRIP */
661 static DEVICE_ATTR_RW(power1_average_max);
662 static DEVICE_ATTR_RW(power1_average_min);
663
664 /* depend on POWER_METER_CAN_CAP */
665 static DEVICE_ATTR_RO(power1_cap_hyst);
666
667 /* depend on POWER_METER_CAN_MEASURE */
668 static DEVICE_ATTR_RO(power1_accuracy);
669 static DEVICE_ATTR_RO(power1_is_battery);
670
671 static DEVICE_ATTR_RO(power1_model_number);
672 static DEVICE_ATTR_RO(power1_oem_info);
673 static DEVICE_ATTR_RO(power1_serial_number);
674
power_extra_is_visible(struct kobject * kobj,struct attribute * attr,int idx)675 static umode_t power_extra_is_visible(struct kobject *kobj,
676 struct attribute *attr, int idx)
677 {
678 struct device *dev = kobj_to_dev(kobj);
679 struct acpi_power_meter_resource *res = dev_get_drvdata(dev);
680
681 if (attr == &dev_attr_power1_is_battery.attr ||
682 attr == &dev_attr_power1_accuracy.attr) {
683 if ((res->caps.flags & POWER_METER_CAN_MEASURE) == 0)
684 return 0;
685 }
686
687 if (attr == &dev_attr_power1_cap_hyst.attr) {
688 if ((res->caps.flags & POWER_METER_CAN_CAP) == 0) {
689 return 0;
690 } else if (!can_cap_in_hardware()) {
691 dev_warn(&res->acpi_dev->dev,
692 "Ignoring unsafe software power cap!\n");
693 return 0;
694 }
695 }
696
697 if (attr == &dev_attr_power1_average_max.attr ||
698 attr == &dev_attr_power1_average_min.attr) {
699 if ((res->caps.flags & POWER_METER_CAN_TRIP) == 0)
700 return 0;
701 }
702
703 return attr->mode;
704 }
705
706 static struct attribute *power_extra_attrs[] = {
707 &dev_attr_power1_average_max.attr,
708 &dev_attr_power1_average_min.attr,
709 &dev_attr_power1_cap_hyst.attr,
710 &dev_attr_power1_accuracy.attr,
711 &dev_attr_power1_is_battery.attr,
712 &dev_attr_power1_model_number.attr,
713 &dev_attr_power1_oem_info.attr,
714 &dev_attr_power1_serial_number.attr,
715 NULL
716 };
717
718 static const struct attribute_group power_extra_group = {
719 .attrs = power_extra_attrs,
720 .is_visible = power_extra_is_visible,
721 };
722
723 __ATTRIBUTE_GROUPS(power_extra);
724
free_capabilities(struct acpi_power_meter_resource * resource)725 static void free_capabilities(struct acpi_power_meter_resource *resource)
726 {
727 acpi_string *str;
728 int i;
729
730 str = &resource->model_number;
731 for (i = 0; i < 3; i++, str++) {
732 kfree(*str);
733 *str = NULL;
734 }
735 }
736
read_capabilities(struct acpi_power_meter_resource * resource)737 static int read_capabilities(struct acpi_power_meter_resource *resource)
738 {
739 int res = 0;
740 int i;
741 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
742 struct acpi_buffer state = { 0, NULL };
743 struct acpi_buffer format = { sizeof("NNNNNNNNNNN"), "NNNNNNNNNNN" };
744 union acpi_object *pss;
745 acpi_string *str;
746 acpi_status status;
747
748 status = acpi_evaluate_object(resource->acpi_dev->handle, "_PMC", NULL,
749 &buffer);
750 if (ACPI_FAILURE(status)) {
751 acpi_evaluation_failure_warn(resource->acpi_dev->handle, "_PMC",
752 status);
753 return -ENODEV;
754 }
755
756 pss = buffer.pointer;
757 if (!pss ||
758 pss->type != ACPI_TYPE_PACKAGE ||
759 pss->package.count != 14) {
760 dev_err(&resource->acpi_dev->dev, ACPI_POWER_METER_NAME
761 "Invalid _PMC data\n");
762 res = -EFAULT;
763 goto end;
764 }
765
766 /* Grab all the integer data at once */
767 state.length = sizeof(struct acpi_power_meter_capabilities);
768 state.pointer = &resource->caps;
769
770 status = acpi_extract_package(pss, &format, &state);
771 if (ACPI_FAILURE(status)) {
772 dev_err(&resource->acpi_dev->dev, ACPI_POWER_METER_NAME
773 "_PMC package parsing failed: %s\n",
774 acpi_format_exception(status));
775 res = -EFAULT;
776 goto end;
777 }
778
779 if (resource->caps.units) {
780 dev_err(&resource->acpi_dev->dev, ACPI_POWER_METER_NAME
781 "Unknown units %llu.\n",
782 resource->caps.units);
783 res = -EINVAL;
784 goto end;
785 }
786
787 /* Grab the string data */
788 str = &resource->model_number;
789
790 for (i = 11; i < 14; i++) {
791 union acpi_object *element = &pss->package.elements[i];
792
793 if (element->type != ACPI_TYPE_STRING) {
794 res = -EINVAL;
795 goto error;
796 }
797
798 *str = kmemdup_nul(element->string.pointer, element->string.length,
799 GFP_KERNEL);
800 if (!*str) {
801 res = -ENOMEM;
802 goto error;
803 }
804
805 str++;
806 }
807
808 dev_info(&resource->acpi_dev->dev, "Found ACPI power meter.\n");
809 goto end;
810 error:
811 free_capabilities(resource);
812 end:
813 kfree(buffer.pointer);
814 return res;
815 }
816
817 /* Handle ACPI event notifications */
acpi_power_meter_notify(struct acpi_device * device,u32 event)818 static void acpi_power_meter_notify(struct acpi_device *device, u32 event)
819 {
820 struct acpi_power_meter_resource *resource;
821 int res;
822
823 if (!device || !acpi_driver_data(device))
824 return;
825
826 resource = acpi_driver_data(device);
827
828 guard(mutex)(&acpi_notify_lock);
829
830 switch (event) {
831 case METER_NOTIFY_CONFIG:
832 if (!IS_ERR(resource->hwmon_dev))
833 hwmon_device_unregister(resource->hwmon_dev);
834
835 mutex_lock(&resource->lock);
836
837 free_capabilities(resource);
838 remove_domain_devices(resource);
839 res = read_capabilities(resource);
840 if (res)
841 dev_err_once(&device->dev, "read capabilities failed.\n");
842 res = read_domain_devices(resource);
843 if (res && res != -ENODEV)
844 dev_err_once(&device->dev, "read domain devices failed.\n");
845
846 mutex_unlock(&resource->lock);
847
848 resource->hwmon_dev =
849 hwmon_device_register_with_info(&device->dev,
850 ACPI_POWER_METER_NAME,
851 resource,
852 &power_meter_chip_info,
853 power_extra_groups);
854 if (IS_ERR(resource->hwmon_dev))
855 dev_err_once(&device->dev, "register hwmon device failed.\n");
856
857 break;
858 case METER_NOTIFY_TRIP:
859 sysfs_notify(&device->dev.kobj, NULL, POWER_AVERAGE_NAME);
860 break;
861 case METER_NOTIFY_CAP:
862 mutex_lock(&resource->lock);
863 res = update_cap(resource);
864 if (res)
865 dev_err_once(&device->dev, "update cap failed when capping value is changed.\n");
866 mutex_unlock(&resource->lock);
867 sysfs_notify(&device->dev.kobj, NULL, POWER_CAP_NAME);
868 break;
869 case METER_NOTIFY_INTERVAL:
870 sysfs_notify(&device->dev.kobj, NULL, POWER_AVG_INTERVAL_NAME);
871 break;
872 case METER_NOTIFY_CAPPING:
873 mutex_lock(&resource->lock);
874 resource->power_alarm = true;
875 mutex_unlock(&resource->lock);
876 sysfs_notify(&device->dev.kobj, NULL, POWER_ALARM_NAME);
877 dev_info(&device->dev, "Capping in progress.\n");
878 break;
879 default:
880 WARN(1, "Unexpected event %d\n", event);
881 break;
882 }
883
884 acpi_bus_generate_netlink_event(ACPI_POWER_METER_CLASS,
885 dev_name(&device->dev), event, 0);
886 }
887
acpi_power_meter_add(struct acpi_device * device)888 static int acpi_power_meter_add(struct acpi_device *device)
889 {
890 int res;
891 struct acpi_power_meter_resource *resource;
892
893 if (!device)
894 return -EINVAL;
895
896 resource = kzalloc(sizeof(*resource), GFP_KERNEL);
897 if (!resource)
898 return -ENOMEM;
899
900 resource->sensors_valid = 0;
901 resource->acpi_dev = device;
902 mutex_init(&resource->lock);
903 strcpy(acpi_device_name(device), ACPI_POWER_METER_DEVICE_NAME);
904 strcpy(acpi_device_class(device), ACPI_POWER_METER_CLASS);
905 device->driver_data = resource;
906
907 #if IS_REACHABLE(CONFIG_ACPI_IPMI)
908 /*
909 * On Dell systems several methods of acpi_power_meter access
910 * variables in IPMI region, so wait until IPMI space handler is
911 * installed by acpi_ipmi and also wait until SMI is selected to make
912 * the space handler fully functional.
913 */
914 if (dmi_match(DMI_SYS_VENDOR, "Dell Inc.")) {
915 struct acpi_device *ipi_device = acpi_dev_get_first_match_dev("IPI0001", NULL, -1);
916
917 if (ipi_device && acpi_wait_for_acpi_ipmi())
918 dev_warn(&device->dev, "Waiting for ACPI IPMI timeout");
919 acpi_dev_put(ipi_device);
920 }
921 #endif
922
923 res = read_capabilities(resource);
924 if (res)
925 goto exit_free;
926
927 resource->trip[0] = -1;
928 resource->trip[1] = -1;
929
930 /* _PMD method is optional. */
931 res = read_domain_devices(resource);
932 if (res && res != -ENODEV)
933 goto exit_free_capability;
934
935 resource->hwmon_dev =
936 hwmon_device_register_with_info(&device->dev,
937 ACPI_POWER_METER_NAME, resource,
938 &power_meter_chip_info,
939 power_extra_groups);
940 if (IS_ERR(resource->hwmon_dev)) {
941 res = PTR_ERR(resource->hwmon_dev);
942 goto exit_remove;
943 }
944
945 res = 0;
946 goto exit;
947
948 exit_remove:
949 remove_domain_devices(resource);
950 exit_free_capability:
951 free_capabilities(resource);
952 exit_free:
953 kfree(resource);
954 exit:
955 return res;
956 }
957
acpi_power_meter_remove(struct acpi_device * device)958 static void acpi_power_meter_remove(struct acpi_device *device)
959 {
960 struct acpi_power_meter_resource *resource;
961
962 if (!device || !acpi_driver_data(device))
963 return;
964
965 resource = acpi_driver_data(device);
966 if (!IS_ERR(resource->hwmon_dev))
967 hwmon_device_unregister(resource->hwmon_dev);
968
969 remove_domain_devices(resource);
970 free_capabilities(resource);
971
972 kfree(resource);
973 }
974
acpi_power_meter_resume(struct device * dev)975 static int acpi_power_meter_resume(struct device *dev)
976 {
977 struct acpi_power_meter_resource *resource;
978
979 if (!dev)
980 return -EINVAL;
981
982 resource = acpi_driver_data(to_acpi_device(dev));
983 if (!resource)
984 return -EINVAL;
985
986 free_capabilities(resource);
987 read_capabilities(resource);
988
989 return 0;
990 }
991
992 static DEFINE_SIMPLE_DEV_PM_OPS(acpi_power_meter_pm, NULL,
993 acpi_power_meter_resume);
994
995 static struct acpi_driver acpi_power_meter_driver = {
996 .name = "power_meter",
997 .class = ACPI_POWER_METER_CLASS,
998 .ids = power_meter_ids,
999 .ops = {
1000 .add = acpi_power_meter_add,
1001 .remove = acpi_power_meter_remove,
1002 .notify = acpi_power_meter_notify,
1003 },
1004 .drv.pm = pm_sleep_ptr(&acpi_power_meter_pm),
1005 };
1006
1007 /* Module init/exit routines */
enable_cap_knobs(const struct dmi_system_id * d)1008 static int __init enable_cap_knobs(const struct dmi_system_id *d)
1009 {
1010 cap_in_hardware = 1;
1011 return 0;
1012 }
1013
1014 static const struct dmi_system_id pm_dmi_table[] __initconst = {
1015 {
1016 enable_cap_knobs, "IBM Active Energy Manager",
1017 {
1018 DMI_MATCH(DMI_SYS_VENDOR, "IBM")
1019 },
1020 },
1021 {}
1022 };
1023
acpi_power_meter_init(void)1024 static int __init acpi_power_meter_init(void)
1025 {
1026 int result;
1027
1028 if (acpi_disabled)
1029 return -ENODEV;
1030
1031 dmi_check_system(pm_dmi_table);
1032
1033 result = acpi_bus_register_driver(&acpi_power_meter_driver);
1034 if (result < 0)
1035 return result;
1036
1037 return 0;
1038 }
1039
acpi_power_meter_exit(void)1040 static void __exit acpi_power_meter_exit(void)
1041 {
1042 acpi_bus_unregister_driver(&acpi_power_meter_driver);
1043 }
1044
1045 MODULE_AUTHOR("Darrick J. Wong <darrick.wong@oracle.com>");
1046 MODULE_DESCRIPTION("ACPI 4.0 power meter driver");
1047 MODULE_LICENSE("GPL");
1048
1049 module_param(force_cap_on, bool, 0644);
1050 MODULE_PARM_DESC(force_cap_on, "Enable power cap even it is unsafe to do so.");
1051
1052 module_init(acpi_power_meter_init);
1053 module_exit(acpi_power_meter_exit);
1054