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
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 int sensors_valid;
88 unsigned long sensors_last_updated;
89 struct sensor_device_attribute sensors[NUM_SENSORS];
90 int num_sensors;
91 s64 trip[2];
92 int num_domain_devices;
93 struct acpi_device **domain_devices;
94 struct kobject *holders_dir;
95 };
96
97 struct sensor_template {
98 char *label;
99 ssize_t (*show)(struct device *dev,
100 struct device_attribute *devattr,
101 char *buf);
102 ssize_t (*set)(struct device *dev,
103 struct device_attribute *devattr,
104 const char *buf, size_t count);
105 int index;
106 };
107
108 /* Averaging interval */
update_avg_interval(struct acpi_power_meter_resource * resource)109 static int update_avg_interval(struct acpi_power_meter_resource *resource)
110 {
111 unsigned long long data;
112 acpi_status status;
113
114 status = acpi_evaluate_integer(resource->acpi_dev->handle, "_GAI",
115 NULL, &data);
116 if (ACPI_FAILURE(status)) {
117 acpi_evaluation_failure_warn(resource->acpi_dev->handle, "_GAI",
118 status);
119 return -ENODEV;
120 }
121
122 resource->avg_interval = data;
123 return 0;
124 }
125
show_avg_interval(struct device * dev,struct device_attribute * devattr,char * buf)126 static ssize_t show_avg_interval(struct device *dev,
127 struct device_attribute *devattr,
128 char *buf)
129 {
130 struct acpi_device *acpi_dev = to_acpi_device(dev);
131 struct acpi_power_meter_resource *resource = acpi_dev->driver_data;
132
133 mutex_lock(&resource->lock);
134 update_avg_interval(resource);
135 mutex_unlock(&resource->lock);
136
137 return sprintf(buf, "%llu\n", resource->avg_interval);
138 }
139
set_avg_interval(struct device * dev,struct device_attribute * devattr,const char * buf,size_t count)140 static ssize_t set_avg_interval(struct device *dev,
141 struct device_attribute *devattr,
142 const char *buf, size_t count)
143 {
144 struct acpi_device *acpi_dev = to_acpi_device(dev);
145 struct acpi_power_meter_resource *resource = acpi_dev->driver_data;
146 union acpi_object arg0 = { ACPI_TYPE_INTEGER };
147 struct acpi_object_list args = { 1, &arg0 };
148 int res;
149 unsigned long temp;
150 unsigned long long data;
151 acpi_status status;
152
153 res = kstrtoul(buf, 10, &temp);
154 if (res)
155 return res;
156
157 if (temp > resource->caps.max_avg_interval ||
158 temp < resource->caps.min_avg_interval)
159 return -EINVAL;
160 arg0.integer.value = temp;
161
162 mutex_lock(&resource->lock);
163 status = acpi_evaluate_integer(resource->acpi_dev->handle, "_PAI",
164 &args, &data);
165 if (ACPI_SUCCESS(status))
166 resource->avg_interval = temp;
167 mutex_unlock(&resource->lock);
168
169 if (ACPI_FAILURE(status)) {
170 acpi_evaluation_failure_warn(resource->acpi_dev->handle, "_PAI",
171 status);
172 return -EINVAL;
173 }
174
175 /* _PAI returns 0 on success, nonzero otherwise */
176 if (data)
177 return -EINVAL;
178
179 return count;
180 }
181
182 /* Cap functions */
update_cap(struct acpi_power_meter_resource * resource)183 static int update_cap(struct acpi_power_meter_resource *resource)
184 {
185 unsigned long long data;
186 acpi_status status;
187
188 status = acpi_evaluate_integer(resource->acpi_dev->handle, "_GHL",
189 NULL, &data);
190 if (ACPI_FAILURE(status)) {
191 acpi_evaluation_failure_warn(resource->acpi_dev->handle, "_GHL",
192 status);
193 return -ENODEV;
194 }
195
196 resource->cap = data;
197 return 0;
198 }
199
show_cap(struct device * dev,struct device_attribute * devattr,char * buf)200 static ssize_t show_cap(struct device *dev,
201 struct device_attribute *devattr,
202 char *buf)
203 {
204 struct acpi_device *acpi_dev = to_acpi_device(dev);
205 struct acpi_power_meter_resource *resource = acpi_dev->driver_data;
206
207 mutex_lock(&resource->lock);
208 update_cap(resource);
209 mutex_unlock(&resource->lock);
210
211 return sprintf(buf, "%llu\n", resource->cap * 1000);
212 }
213
set_cap(struct device * dev,struct device_attribute * devattr,const char * buf,size_t count)214 static ssize_t set_cap(struct device *dev, struct device_attribute *devattr,
215 const char *buf, size_t count)
216 {
217 struct acpi_device *acpi_dev = to_acpi_device(dev);
218 struct acpi_power_meter_resource *resource = acpi_dev->driver_data;
219 union acpi_object arg0 = { ACPI_TYPE_INTEGER };
220 struct acpi_object_list args = { 1, &arg0 };
221 int res;
222 unsigned long temp;
223 unsigned long long data;
224 acpi_status status;
225
226 res = kstrtoul(buf, 10, &temp);
227 if (res)
228 return res;
229
230 temp = DIV_ROUND_CLOSEST(temp, 1000);
231 if (temp > resource->caps.max_cap || temp < resource->caps.min_cap)
232 return -EINVAL;
233 arg0.integer.value = temp;
234
235 mutex_lock(&resource->lock);
236 status = acpi_evaluate_integer(resource->acpi_dev->handle, "_SHL",
237 &args, &data);
238 if (ACPI_SUCCESS(status))
239 resource->cap = temp;
240 mutex_unlock(&resource->lock);
241
242 if (ACPI_FAILURE(status)) {
243 acpi_evaluation_failure_warn(resource->acpi_dev->handle, "_SHL",
244 status);
245 return -EINVAL;
246 }
247
248 /* _SHL returns 0 on success, nonzero otherwise */
249 if (data)
250 return -EINVAL;
251
252 return count;
253 }
254
255 /* Power meter trip points */
set_acpi_trip(struct acpi_power_meter_resource * resource)256 static int set_acpi_trip(struct acpi_power_meter_resource *resource)
257 {
258 union acpi_object arg_objs[] = {
259 {ACPI_TYPE_INTEGER},
260 {ACPI_TYPE_INTEGER}
261 };
262 struct acpi_object_list args = { 2, arg_objs };
263 unsigned long long data;
264 acpi_status status;
265
266 /* Both trip levels must be set */
267 if (resource->trip[0] < 0 || resource->trip[1] < 0)
268 return 0;
269
270 /* This driver stores min, max; ACPI wants max, min. */
271 arg_objs[0].integer.value = resource->trip[1];
272 arg_objs[1].integer.value = resource->trip[0];
273
274 status = acpi_evaluate_integer(resource->acpi_dev->handle, "_PTP",
275 &args, &data);
276 if (ACPI_FAILURE(status)) {
277 acpi_evaluation_failure_warn(resource->acpi_dev->handle, "_PTP",
278 status);
279 return -EINVAL;
280 }
281
282 /* _PTP returns 0 on success, nonzero otherwise */
283 if (data)
284 return -EINVAL;
285
286 return 0;
287 }
288
set_trip(struct device * dev,struct device_attribute * devattr,const char * buf,size_t count)289 static ssize_t set_trip(struct device *dev, struct device_attribute *devattr,
290 const char *buf, size_t count)
291 {
292 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
293 struct acpi_device *acpi_dev = to_acpi_device(dev);
294 struct acpi_power_meter_resource *resource = acpi_dev->driver_data;
295 int res;
296 unsigned long temp;
297
298 res = kstrtoul(buf, 10, &temp);
299 if (res)
300 return res;
301
302 temp = DIV_ROUND_CLOSEST(temp, 1000);
303
304 mutex_lock(&resource->lock);
305 resource->trip[attr->index - 7] = temp;
306 res = set_acpi_trip(resource);
307 mutex_unlock(&resource->lock);
308
309 if (res)
310 return res;
311
312 return count;
313 }
314
315 /* Power meter */
update_meter(struct acpi_power_meter_resource * resource)316 static int update_meter(struct acpi_power_meter_resource *resource)
317 {
318 unsigned long long data;
319 acpi_status status;
320 unsigned long local_jiffies = jiffies;
321
322 if (time_before(local_jiffies, resource->sensors_last_updated +
323 msecs_to_jiffies(resource->caps.sampling_time)) &&
324 resource->sensors_valid)
325 return 0;
326
327 status = acpi_evaluate_integer(resource->acpi_dev->handle, "_PMM",
328 NULL, &data);
329 if (ACPI_FAILURE(status)) {
330 acpi_evaluation_failure_warn(resource->acpi_dev->handle, "_PMM",
331 status);
332 return -ENODEV;
333 }
334
335 resource->power = data;
336 resource->sensors_valid = 1;
337 resource->sensors_last_updated = jiffies;
338 return 0;
339 }
340
show_power(struct device * dev,struct device_attribute * devattr,char * buf)341 static ssize_t show_power(struct device *dev,
342 struct device_attribute *devattr,
343 char *buf)
344 {
345 struct acpi_device *acpi_dev = to_acpi_device(dev);
346 struct acpi_power_meter_resource *resource = acpi_dev->driver_data;
347
348 mutex_lock(&resource->lock);
349 update_meter(resource);
350 mutex_unlock(&resource->lock);
351
352 if (resource->power == UNKNOWN_POWER)
353 return -ENODATA;
354
355 return sprintf(buf, "%llu\n", resource->power * 1000);
356 }
357
358 /* Miscellaneous */
show_str(struct device * dev,struct device_attribute * devattr,char * buf)359 static ssize_t show_str(struct device *dev,
360 struct device_attribute *devattr,
361 char *buf)
362 {
363 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
364 struct acpi_device *acpi_dev = to_acpi_device(dev);
365 struct acpi_power_meter_resource *resource = acpi_dev->driver_data;
366 acpi_string val;
367 int ret;
368
369 mutex_lock(&resource->lock);
370 switch (attr->index) {
371 case 0:
372 val = resource->model_number;
373 break;
374 case 1:
375 val = resource->serial_number;
376 break;
377 case 2:
378 val = resource->oem_info;
379 break;
380 default:
381 WARN(1, "Implementation error: unexpected attribute index %d\n",
382 attr->index);
383 val = "";
384 break;
385 }
386 ret = sprintf(buf, "%s\n", val);
387 mutex_unlock(&resource->lock);
388 return ret;
389 }
390
show_val(struct device * dev,struct device_attribute * devattr,char * buf)391 static ssize_t show_val(struct device *dev,
392 struct device_attribute *devattr,
393 char *buf)
394 {
395 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
396 struct acpi_device *acpi_dev = to_acpi_device(dev);
397 struct acpi_power_meter_resource *resource = acpi_dev->driver_data;
398 u64 val = 0;
399
400 switch (attr->index) {
401 case 0:
402 val = resource->caps.min_avg_interval;
403 break;
404 case 1:
405 val = resource->caps.max_avg_interval;
406 break;
407 case 2:
408 val = resource->caps.min_cap * 1000;
409 break;
410 case 3:
411 val = resource->caps.max_cap * 1000;
412 break;
413 case 4:
414 if (resource->caps.hysteresis == UNKNOWN_HYSTERESIS)
415 return sprintf(buf, "unknown\n");
416
417 val = resource->caps.hysteresis * 1000;
418 break;
419 case 5:
420 if (resource->caps.flags & POWER_METER_IS_BATTERY)
421 val = 1;
422 else
423 val = 0;
424 break;
425 case 6:
426 if (resource->power > resource->cap)
427 val = 1;
428 else
429 val = 0;
430 break;
431 case 7:
432 case 8:
433 if (resource->trip[attr->index - 7] < 0)
434 return sprintf(buf, "unknown\n");
435
436 val = resource->trip[attr->index - 7] * 1000;
437 break;
438 default:
439 WARN(1, "Implementation error: unexpected attribute index %d\n",
440 attr->index);
441 break;
442 }
443
444 return sprintf(buf, "%llu\n", val);
445 }
446
show_accuracy(struct device * dev,struct device_attribute * devattr,char * buf)447 static ssize_t show_accuracy(struct device *dev,
448 struct device_attribute *devattr,
449 char *buf)
450 {
451 struct acpi_device *acpi_dev = to_acpi_device(dev);
452 struct acpi_power_meter_resource *resource = acpi_dev->driver_data;
453 unsigned int acc = resource->caps.accuracy;
454
455 return sprintf(buf, "%u.%u%%\n", acc / 1000, acc % 1000);
456 }
457
show_name(struct device * dev,struct device_attribute * devattr,char * buf)458 static ssize_t show_name(struct device *dev,
459 struct device_attribute *devattr,
460 char *buf)
461 {
462 return sprintf(buf, "%s\n", ACPI_POWER_METER_NAME);
463 }
464
465 #define RO_SENSOR_TEMPLATE(_label, _show, _index) \
466 { \
467 .label = _label, \
468 .show = _show, \
469 .index = _index, \
470 }
471
472 #define RW_SENSOR_TEMPLATE(_label, _show, _set, _index) \
473 { \
474 .label = _label, \
475 .show = _show, \
476 .set = _set, \
477 .index = _index, \
478 }
479
480 /* Sensor descriptions. If you add a sensor, update NUM_SENSORS above! */
481 static struct sensor_template meter_attrs[] = {
482 RO_SENSOR_TEMPLATE(POWER_AVERAGE_NAME, show_power, 0),
483 RO_SENSOR_TEMPLATE("power1_accuracy", show_accuracy, 0),
484 RO_SENSOR_TEMPLATE("power1_average_interval_min", show_val, 0),
485 RO_SENSOR_TEMPLATE("power1_average_interval_max", show_val, 1),
486 RO_SENSOR_TEMPLATE("power1_is_battery", show_val, 5),
487 RW_SENSOR_TEMPLATE(POWER_AVG_INTERVAL_NAME, show_avg_interval,
488 set_avg_interval, 0),
489 {},
490 };
491
492 static struct sensor_template misc_cap_attrs[] = {
493 RO_SENSOR_TEMPLATE("power1_cap_min", show_val, 2),
494 RO_SENSOR_TEMPLATE("power1_cap_max", show_val, 3),
495 RO_SENSOR_TEMPLATE("power1_cap_hyst", show_val, 4),
496 RO_SENSOR_TEMPLATE(POWER_ALARM_NAME, show_val, 6),
497 {},
498 };
499
500 static struct sensor_template ro_cap_attrs[] = {
501 RO_SENSOR_TEMPLATE(POWER_CAP_NAME, show_cap, 0),
502 {},
503 };
504
505 static struct sensor_template rw_cap_attrs[] = {
506 RW_SENSOR_TEMPLATE(POWER_CAP_NAME, show_cap, set_cap, 0),
507 {},
508 };
509
510 static struct sensor_template trip_attrs[] = {
511 RW_SENSOR_TEMPLATE("power1_average_min", show_val, set_trip, 7),
512 RW_SENSOR_TEMPLATE("power1_average_max", show_val, set_trip, 8),
513 {},
514 };
515
516 static struct sensor_template misc_attrs[] = {
517 RO_SENSOR_TEMPLATE("name", show_name, 0),
518 RO_SENSOR_TEMPLATE("power1_model_number", show_str, 0),
519 RO_SENSOR_TEMPLATE("power1_oem_info", show_str, 2),
520 RO_SENSOR_TEMPLATE("power1_serial_number", show_str, 1),
521 {},
522 };
523
524 #undef RO_SENSOR_TEMPLATE
525 #undef RW_SENSOR_TEMPLATE
526
527 /* Read power domain data */
remove_domain_devices(struct acpi_power_meter_resource * resource)528 static void remove_domain_devices(struct acpi_power_meter_resource *resource)
529 {
530 int i;
531
532 if (!resource->num_domain_devices)
533 return;
534
535 for (i = 0; i < resource->num_domain_devices; i++) {
536 struct acpi_device *obj = resource->domain_devices[i];
537
538 if (!obj)
539 continue;
540
541 sysfs_remove_link(resource->holders_dir,
542 kobject_name(&obj->dev.kobj));
543 acpi_dev_put(obj);
544 }
545
546 kfree(resource->domain_devices);
547 kobject_put(resource->holders_dir);
548 resource->num_domain_devices = 0;
549 }
550
read_domain_devices(struct acpi_power_meter_resource * resource)551 static int read_domain_devices(struct acpi_power_meter_resource *resource)
552 {
553 int res = 0;
554 int i;
555 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
556 union acpi_object *pss;
557 acpi_status status;
558
559 status = acpi_evaluate_object(resource->acpi_dev->handle, "_PMD", NULL,
560 &buffer);
561 if (ACPI_FAILURE(status)) {
562 acpi_evaluation_failure_warn(resource->acpi_dev->handle, "_PMD",
563 status);
564 return -ENODEV;
565 }
566
567 pss = buffer.pointer;
568 if (!pss ||
569 pss->type != ACPI_TYPE_PACKAGE) {
570 dev_err(&resource->acpi_dev->dev, ACPI_POWER_METER_NAME
571 "Invalid _PMD data\n");
572 res = -EFAULT;
573 goto end;
574 }
575
576 if (!pss->package.count)
577 goto end;
578
579 resource->domain_devices = kcalloc(pss->package.count,
580 sizeof(struct acpi_device *),
581 GFP_KERNEL);
582 if (!resource->domain_devices) {
583 res = -ENOMEM;
584 goto end;
585 }
586
587 resource->holders_dir = kobject_create_and_add("measures",
588 &resource->acpi_dev->dev.kobj);
589 if (!resource->holders_dir) {
590 res = -ENOMEM;
591 goto exit_free;
592 }
593
594 resource->num_domain_devices = pss->package.count;
595
596 for (i = 0; i < pss->package.count; i++) {
597 struct acpi_device *obj;
598 union acpi_object *element = &pss->package.elements[i];
599
600 /* Refuse non-references */
601 if (element->type != ACPI_TYPE_LOCAL_REFERENCE)
602 continue;
603
604 /* Create a symlink to domain objects */
605 obj = acpi_get_acpi_dev(element->reference.handle);
606 resource->domain_devices[i] = obj;
607 if (!obj)
608 continue;
609
610 res = sysfs_create_link(resource->holders_dir, &obj->dev.kobj,
611 kobject_name(&obj->dev.kobj));
612 if (res) {
613 acpi_dev_put(obj);
614 resource->domain_devices[i] = NULL;
615 }
616 }
617
618 res = 0;
619 goto end;
620
621 exit_free:
622 kfree(resource->domain_devices);
623 end:
624 kfree(buffer.pointer);
625 return res;
626 }
627
628 /* Registration and deregistration */
register_attrs(struct acpi_power_meter_resource * resource,struct sensor_template * attrs)629 static int register_attrs(struct acpi_power_meter_resource *resource,
630 struct sensor_template *attrs)
631 {
632 struct device *dev = &resource->acpi_dev->dev;
633 struct sensor_device_attribute *sensors =
634 &resource->sensors[resource->num_sensors];
635 int res = 0;
636
637 while (attrs->label) {
638 sensors->dev_attr.attr.name = attrs->label;
639 sensors->dev_attr.attr.mode = 0444;
640 sensors->dev_attr.show = attrs->show;
641 sensors->index = attrs->index;
642
643 if (attrs->set) {
644 sensors->dev_attr.attr.mode |= 0200;
645 sensors->dev_attr.store = attrs->set;
646 }
647
648 sysfs_attr_init(&sensors->dev_attr.attr);
649 res = device_create_file(dev, &sensors->dev_attr);
650 if (res) {
651 sensors->dev_attr.attr.name = NULL;
652 goto error;
653 }
654 sensors++;
655 resource->num_sensors++;
656 attrs++;
657 }
658
659 error:
660 return res;
661 }
662
remove_attrs(struct acpi_power_meter_resource * resource)663 static void remove_attrs(struct acpi_power_meter_resource *resource)
664 {
665 int i;
666
667 for (i = 0; i < resource->num_sensors; i++) {
668 if (!resource->sensors[i].dev_attr.attr.name)
669 continue;
670 device_remove_file(&resource->acpi_dev->dev,
671 &resource->sensors[i].dev_attr);
672 }
673
674 remove_domain_devices(resource);
675
676 resource->num_sensors = 0;
677 }
678
setup_attrs(struct acpi_power_meter_resource * resource)679 static int setup_attrs(struct acpi_power_meter_resource *resource)
680 {
681 int res = 0;
682
683 res = read_domain_devices(resource);
684 if (res)
685 return res;
686
687 if (resource->caps.flags & POWER_METER_CAN_MEASURE) {
688 res = register_attrs(resource, meter_attrs);
689 if (res)
690 goto error;
691 }
692
693 if (resource->caps.flags & POWER_METER_CAN_CAP) {
694 if (!can_cap_in_hardware()) {
695 dev_warn(&resource->acpi_dev->dev,
696 "Ignoring unsafe software power cap!\n");
697 goto skip_unsafe_cap;
698 }
699
700 if (resource->caps.configurable_cap)
701 res = register_attrs(resource, rw_cap_attrs);
702 else
703 res = register_attrs(resource, ro_cap_attrs);
704
705 if (res)
706 goto error;
707
708 res = register_attrs(resource, misc_cap_attrs);
709 if (res)
710 goto error;
711 }
712
713 skip_unsafe_cap:
714 if (resource->caps.flags & POWER_METER_CAN_TRIP) {
715 res = register_attrs(resource, trip_attrs);
716 if (res)
717 goto error;
718 }
719
720 res = register_attrs(resource, misc_attrs);
721 if (res)
722 goto error;
723
724 return res;
725 error:
726 remove_attrs(resource);
727 return res;
728 }
729
free_capabilities(struct acpi_power_meter_resource * resource)730 static void free_capabilities(struct acpi_power_meter_resource *resource)
731 {
732 acpi_string *str;
733 int i;
734
735 str = &resource->model_number;
736 for (i = 0; i < 3; i++, str++) {
737 kfree(*str);
738 *str = NULL;
739 }
740 }
741
read_capabilities(struct acpi_power_meter_resource * resource)742 static int read_capabilities(struct acpi_power_meter_resource *resource)
743 {
744 int res = 0;
745 int i;
746 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
747 struct acpi_buffer state = { 0, NULL };
748 struct acpi_buffer format = { sizeof("NNNNNNNNNNN"), "NNNNNNNNNNN" };
749 union acpi_object *pss;
750 acpi_string *str;
751 acpi_status status;
752
753 status = acpi_evaluate_object(resource->acpi_dev->handle, "_PMC", NULL,
754 &buffer);
755 if (ACPI_FAILURE(status)) {
756 acpi_evaluation_failure_warn(resource->acpi_dev->handle, "_PMC",
757 status);
758 return -ENODEV;
759 }
760
761 pss = buffer.pointer;
762 if (!pss ||
763 pss->type != ACPI_TYPE_PACKAGE ||
764 pss->package.count != 14) {
765 dev_err(&resource->acpi_dev->dev, ACPI_POWER_METER_NAME
766 "Invalid _PMC data\n");
767 res = -EFAULT;
768 goto end;
769 }
770
771 /* Grab all the integer data at once */
772 state.length = sizeof(struct acpi_power_meter_capabilities);
773 state.pointer = &resource->caps;
774
775 status = acpi_extract_package(pss, &format, &state);
776 if (ACPI_FAILURE(status)) {
777 dev_err(&resource->acpi_dev->dev, ACPI_POWER_METER_NAME
778 "_PMC package parsing failed: %s\n",
779 acpi_format_exception(status));
780 res = -EFAULT;
781 goto end;
782 }
783
784 if (resource->caps.units) {
785 dev_err(&resource->acpi_dev->dev, ACPI_POWER_METER_NAME
786 "Unknown units %llu.\n",
787 resource->caps.units);
788 res = -EINVAL;
789 goto end;
790 }
791
792 /* Grab the string data */
793 str = &resource->model_number;
794
795 for (i = 11; i < 14; i++) {
796 union acpi_object *element = &pss->package.elements[i];
797
798 if (element->type != ACPI_TYPE_STRING) {
799 res = -EINVAL;
800 goto error;
801 }
802
803 *str = kcalloc(element->string.length + 1, sizeof(u8),
804 GFP_KERNEL);
805 if (!*str) {
806 res = -ENOMEM;
807 goto error;
808 }
809
810 strncpy(*str, element->string.pointer, element->string.length);
811 str++;
812 }
813
814 dev_info(&resource->acpi_dev->dev, "Found ACPI power meter.\n");
815 goto end;
816 error:
817 free_capabilities(resource);
818 end:
819 kfree(buffer.pointer);
820 return res;
821 }
822
823 /* Handle ACPI event notifications */
acpi_power_meter_notify(struct acpi_device * device,u32 event)824 static void acpi_power_meter_notify(struct acpi_device *device, u32 event)
825 {
826 struct acpi_power_meter_resource *resource;
827 int res;
828
829 if (!device || !acpi_driver_data(device))
830 return;
831
832 resource = acpi_driver_data(device);
833
834 switch (event) {
835 case METER_NOTIFY_CONFIG:
836 mutex_lock(&resource->lock);
837 free_capabilities(resource);
838 res = read_capabilities(resource);
839 mutex_unlock(&resource->lock);
840 if (res)
841 break;
842
843 remove_attrs(resource);
844 setup_attrs(resource);
845 break;
846 case METER_NOTIFY_TRIP:
847 sysfs_notify(&device->dev.kobj, NULL, POWER_AVERAGE_NAME);
848 break;
849 case METER_NOTIFY_CAP:
850 sysfs_notify(&device->dev.kobj, NULL, POWER_CAP_NAME);
851 break;
852 case METER_NOTIFY_INTERVAL:
853 sysfs_notify(&device->dev.kobj, NULL, POWER_AVG_INTERVAL_NAME);
854 break;
855 case METER_NOTIFY_CAPPING:
856 sysfs_notify(&device->dev.kobj, NULL, POWER_ALARM_NAME);
857 dev_info(&device->dev, "Capping in progress.\n");
858 break;
859 default:
860 WARN(1, "Unexpected event %d\n", event);
861 break;
862 }
863
864 acpi_bus_generate_netlink_event(ACPI_POWER_METER_CLASS,
865 dev_name(&device->dev), event, 0);
866 }
867
acpi_power_meter_add(struct acpi_device * device)868 static int acpi_power_meter_add(struct acpi_device *device)
869 {
870 int res;
871 struct acpi_power_meter_resource *resource;
872
873 if (!device)
874 return -EINVAL;
875
876 resource = kzalloc(sizeof(*resource), GFP_KERNEL);
877 if (!resource)
878 return -ENOMEM;
879
880 resource->sensors_valid = 0;
881 resource->acpi_dev = device;
882 mutex_init(&resource->lock);
883 strcpy(acpi_device_name(device), ACPI_POWER_METER_DEVICE_NAME);
884 strcpy(acpi_device_class(device), ACPI_POWER_METER_CLASS);
885 device->driver_data = resource;
886
887 res = read_capabilities(resource);
888 if (res)
889 goto exit_free;
890
891 resource->trip[0] = -1;
892 resource->trip[1] = -1;
893
894 res = setup_attrs(resource);
895 if (res)
896 goto exit_free_capability;
897
898 resource->hwmon_dev = hwmon_device_register(&device->dev);
899 if (IS_ERR(resource->hwmon_dev)) {
900 res = PTR_ERR(resource->hwmon_dev);
901 goto exit_remove;
902 }
903
904 res = 0;
905 goto exit;
906
907 exit_remove:
908 remove_attrs(resource);
909 exit_free_capability:
910 free_capabilities(resource);
911 exit_free:
912 kfree(resource);
913 exit:
914 return res;
915 }
916
acpi_power_meter_remove(struct acpi_device * device)917 static void acpi_power_meter_remove(struct acpi_device *device)
918 {
919 struct acpi_power_meter_resource *resource;
920
921 if (!device || !acpi_driver_data(device))
922 return;
923
924 resource = acpi_driver_data(device);
925 hwmon_device_unregister(resource->hwmon_dev);
926
927 remove_attrs(resource);
928 free_capabilities(resource);
929
930 kfree(resource);
931 }
932
acpi_power_meter_resume(struct device * dev)933 static int acpi_power_meter_resume(struct device *dev)
934 {
935 struct acpi_power_meter_resource *resource;
936
937 if (!dev)
938 return -EINVAL;
939
940 resource = acpi_driver_data(to_acpi_device(dev));
941 if (!resource)
942 return -EINVAL;
943
944 free_capabilities(resource);
945 read_capabilities(resource);
946
947 return 0;
948 }
949
950 static DEFINE_SIMPLE_DEV_PM_OPS(acpi_power_meter_pm, NULL,
951 acpi_power_meter_resume);
952
953 static struct acpi_driver acpi_power_meter_driver = {
954 .name = "power_meter",
955 .class = ACPI_POWER_METER_CLASS,
956 .ids = power_meter_ids,
957 .ops = {
958 .add = acpi_power_meter_add,
959 .remove = acpi_power_meter_remove,
960 .notify = acpi_power_meter_notify,
961 },
962 .drv.pm = pm_sleep_ptr(&acpi_power_meter_pm),
963 };
964
965 /* Module init/exit routines */
enable_cap_knobs(const struct dmi_system_id * d)966 static int __init enable_cap_knobs(const struct dmi_system_id *d)
967 {
968 cap_in_hardware = 1;
969 return 0;
970 }
971
972 static const struct dmi_system_id pm_dmi_table[] __initconst = {
973 {
974 enable_cap_knobs, "IBM Active Energy Manager",
975 {
976 DMI_MATCH(DMI_SYS_VENDOR, "IBM")
977 },
978 },
979 {}
980 };
981
acpi_power_meter_init(void)982 static int __init acpi_power_meter_init(void)
983 {
984 int result;
985
986 if (acpi_disabled)
987 return -ENODEV;
988
989 dmi_check_system(pm_dmi_table);
990
991 result = acpi_bus_register_driver(&acpi_power_meter_driver);
992 if (result < 0)
993 return result;
994
995 return 0;
996 }
997
acpi_power_meter_exit(void)998 static void __exit acpi_power_meter_exit(void)
999 {
1000 acpi_bus_unregister_driver(&acpi_power_meter_driver);
1001 }
1002
1003 MODULE_AUTHOR("Darrick J. Wong <darrick.wong@oracle.com>");
1004 MODULE_DESCRIPTION("ACPI 4.0 power meter driver");
1005 MODULE_LICENSE("GPL");
1006
1007 module_param(force_cap_on, bool, 0644);
1008 MODULE_PARM_DESC(force_cap_on, "Enable power cap even it is unsafe to do so.");
1009
1010 module_init(acpi_power_meter_init);
1011 module_exit(acpi_power_meter_exit);
1012