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