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
35#define METER_NOTIFY_CONFIG 0x80
36#define METER_NOTIFY_TRIP 0x81
37#define METER_NOTIFY_CAP 0x82
38#define METER_NOTIFY_CAPPING 0x83
39#define METER_NOTIFY_INTERVAL 0x84
40
41#define POWER_AVERAGE_NAME "power1_average"
42#define POWER_CAP_NAME "power1_cap"
43#define POWER_AVG_INTERVAL_NAME "power1_average_interval"
44#define POWER_ALARM_NAME "power1_alarm"
45
46static int cap_in_hardware;
47static bool force_cap_on;
48
49static int can_cap_in_hardware(void)
50{
51 return force_cap_on || cap_in_hardware;
52}
53
54static const struct acpi_device_id power_meter_ids[] = {
55 {"ACPI000D", 0},
56 {"", 0},
57};
58MODULE_DEVICE_TABLE(acpi, power_meter_ids);
59
60struct acpi_power_meter_capabilities {
61 u64 flags;
62 u64 units;
63 u64 type;
64 u64 accuracy;
65 u64 sampling_time;
66 u64 min_avg_interval;
67 u64 max_avg_interval;
68 u64 hysteresis;
69 u64 configurable_cap;
70 u64 min_cap;
71 u64 max_cap;
72};
73
74struct acpi_power_meter_resource {
75 struct acpi_device *acpi_dev;
76 acpi_bus_id name;
77 struct mutex lock;
78 struct device *hwmon_dev;
79 struct acpi_power_meter_capabilities caps;
80 acpi_string model_number;
81 acpi_string serial_number;
82 acpi_string oem_info;
83 u64 power;
84 u64 cap;
85 u64 avg_interval;
86 int sensors_valid;
87 unsigned long sensors_last_updated;
88 struct sensor_device_attribute sensors[NUM_SENSORS];
89 int num_sensors;
90 s64 trip[2];
91 int num_domain_devices;
92 struct acpi_device **domain_devices;
93 struct kobject *holders_dir;
94};
95
96struct sensor_template {
97 char *label;
98 ssize_t (*show)(struct device *dev,
99 struct device_attribute *devattr,
100 char *buf);
101 ssize_t (*set)(struct device *dev,
102 struct device_attribute *devattr,
103 const char *buf, size_t count);
104 int index;
105};
106
107/* Averaging interval */
108static int update_avg_interval(struct acpi_power_meter_resource *resource)
109{
110 unsigned long long data;
111 acpi_status status;
112
113 status = acpi_evaluate_integer(handle: resource->acpi_dev->handle, pathname: "_GAI",
114 NULL, data: &data);
115 if (ACPI_FAILURE(status)) {
116 acpi_evaluation_failure_warn(handle: resource->acpi_dev->handle, name: "_GAI",
117 status);
118 return -ENODEV;
119 }
120
121 resource->avg_interval = data;
122 return 0;
123}
124
125static ssize_t show_avg_interval(struct device *dev,
126 struct device_attribute *devattr,
127 char *buf)
128{
129 struct acpi_device *acpi_dev = to_acpi_device(dev);
130 struct acpi_power_meter_resource *resource = acpi_dev->driver_data;
131
132 mutex_lock(&resource->lock);
133 update_avg_interval(resource);
134 mutex_unlock(lock: &resource->lock);
135
136 return sprintf(buf, fmt: "%llu\n", resource->avg_interval);
137}
138
139static ssize_t set_avg_interval(struct device *dev,
140 struct device_attribute *devattr,
141 const char *buf, size_t count)
142{
143 struct acpi_device *acpi_dev = to_acpi_device(dev);
144 struct acpi_power_meter_resource *resource = acpi_dev->driver_data;
145 union acpi_object arg0 = { ACPI_TYPE_INTEGER };
146 struct acpi_object_list args = { 1, &arg0 };
147 int res;
148 unsigned long temp;
149 unsigned long long data;
150 acpi_status status;
151
152 res = kstrtoul(s: buf, base: 10, res: &temp);
153 if (res)
154 return res;
155
156 if (temp > resource->caps.max_avg_interval ||
157 temp < resource->caps.min_avg_interval)
158 return -EINVAL;
159 arg0.integer.value = temp;
160
161 mutex_lock(&resource->lock);
162 status = acpi_evaluate_integer(handle: resource->acpi_dev->handle, pathname: "_PAI",
163 arguments: &args, data: &data);
164 if (ACPI_SUCCESS(status))
165 resource->avg_interval = temp;
166 mutex_unlock(lock: &resource->lock);
167
168 if (ACPI_FAILURE(status)) {
169 acpi_evaluation_failure_warn(handle: resource->acpi_dev->handle, name: "_PAI",
170 status);
171 return -EINVAL;
172 }
173
174 /* _PAI returns 0 on success, nonzero otherwise */
175 if (data)
176 return -EINVAL;
177
178 return count;
179}
180
181/* Cap functions */
182static int update_cap(struct acpi_power_meter_resource *resource)
183{
184 unsigned long long data;
185 acpi_status status;
186
187 status = acpi_evaluate_integer(handle: resource->acpi_dev->handle, pathname: "_GHL",
188 NULL, data: &data);
189 if (ACPI_FAILURE(status)) {
190 acpi_evaluation_failure_warn(handle: resource->acpi_dev->handle, name: "_GHL",
191 status);
192 return -ENODEV;
193 }
194
195 resource->cap = data;
196 return 0;
197}
198
199static ssize_t show_cap(struct device *dev,
200 struct device_attribute *devattr,
201 char *buf)
202{
203 struct acpi_device *acpi_dev = to_acpi_device(dev);
204 struct acpi_power_meter_resource *resource = acpi_dev->driver_data;
205
206 mutex_lock(&resource->lock);
207 update_cap(resource);
208 mutex_unlock(lock: &resource->lock);
209
210 return sprintf(buf, fmt: "%llu\n", resource->cap * 1000);
211}
212
213static ssize_t set_cap(struct device *dev, struct device_attribute *devattr,
214 const char *buf, size_t count)
215{
216 struct acpi_device *acpi_dev = to_acpi_device(dev);
217 struct acpi_power_meter_resource *resource = acpi_dev->driver_data;
218 union acpi_object arg0 = { ACPI_TYPE_INTEGER };
219 struct acpi_object_list args = { 1, &arg0 };
220 int res;
221 unsigned long temp;
222 unsigned long long data;
223 acpi_status status;
224
225 res = kstrtoul(s: buf, base: 10, res: &temp);
226 if (res)
227 return res;
228
229 temp = DIV_ROUND_CLOSEST(temp, 1000);
230 if (temp > resource->caps.max_cap || temp < resource->caps.min_cap)
231 return -EINVAL;
232 arg0.integer.value = temp;
233
234 mutex_lock(&resource->lock);
235 status = acpi_evaluate_integer(handle: resource->acpi_dev->handle, pathname: "_SHL",
236 arguments: &args, data: &data);
237 if (ACPI_SUCCESS(status))
238 resource->cap = temp;
239 mutex_unlock(lock: &resource->lock);
240
241 if (ACPI_FAILURE(status)) {
242 acpi_evaluation_failure_warn(handle: resource->acpi_dev->handle, name: "_SHL",
243 status);
244 return -EINVAL;
245 }
246
247 /* _SHL returns 0 on success, nonzero otherwise */
248 if (data)
249 return -EINVAL;
250
251 return count;
252}
253
254/* Power meter trip points */
255static int set_acpi_trip(struct acpi_power_meter_resource *resource)
256{
257 union acpi_object arg_objs[] = {
258 {ACPI_TYPE_INTEGER},
259 {ACPI_TYPE_INTEGER}
260 };
261 struct acpi_object_list args = { 2, arg_objs };
262 unsigned long long data;
263 acpi_status status;
264
265 /* Both trip levels must be set */
266 if (resource->trip[0] < 0 || resource->trip[1] < 0)
267 return 0;
268
269 /* This driver stores min, max; ACPI wants max, min. */
270 arg_objs[0].integer.value = resource->trip[1];
271 arg_objs[1].integer.value = resource->trip[0];
272
273 status = acpi_evaluate_integer(handle: resource->acpi_dev->handle, pathname: "_PTP",
274 arguments: &args, data: &data);
275 if (ACPI_FAILURE(status)) {
276 acpi_evaluation_failure_warn(handle: resource->acpi_dev->handle, name: "_PTP",
277 status);
278 return -EINVAL;
279 }
280
281 /* _PTP returns 0 on success, nonzero otherwise */
282 if (data)
283 return -EINVAL;
284
285 return 0;
286}
287
288static ssize_t set_trip(struct device *dev, struct device_attribute *devattr,
289 const char *buf, size_t count)
290{
291 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
292 struct acpi_device *acpi_dev = to_acpi_device(dev);
293 struct acpi_power_meter_resource *resource = acpi_dev->driver_data;
294 int res;
295 unsigned long temp;
296
297 res = kstrtoul(s: buf, base: 10, res: &temp);
298 if (res)
299 return res;
300
301 temp = DIV_ROUND_CLOSEST(temp, 1000);
302
303 mutex_lock(&resource->lock);
304 resource->trip[attr->index - 7] = temp;
305 res = set_acpi_trip(resource);
306 mutex_unlock(lock: &resource->lock);
307
308 if (res)
309 return res;
310
311 return count;
312}
313
314/* Power meter */
315static int update_meter(struct acpi_power_meter_resource *resource)
316{
317 unsigned long long data;
318 acpi_status status;
319 unsigned long local_jiffies = jiffies;
320
321 if (time_before(local_jiffies, resource->sensors_last_updated +
322 msecs_to_jiffies(resource->caps.sampling_time)) &&
323 resource->sensors_valid)
324 return 0;
325
326 status = acpi_evaluate_integer(handle: resource->acpi_dev->handle, pathname: "_PMM",
327 NULL, data: &data);
328 if (ACPI_FAILURE(status)) {
329 acpi_evaluation_failure_warn(handle: resource->acpi_dev->handle, name: "_PMM",
330 status);
331 return -ENODEV;
332 }
333
334 resource->power = data;
335 resource->sensors_valid = 1;
336 resource->sensors_last_updated = jiffies;
337 return 0;
338}
339
340static ssize_t show_power(struct device *dev,
341 struct device_attribute *devattr,
342 char *buf)
343{
344 struct acpi_device *acpi_dev = to_acpi_device(dev);
345 struct acpi_power_meter_resource *resource = acpi_dev->driver_data;
346
347 mutex_lock(&resource->lock);
348 update_meter(resource);
349 mutex_unlock(lock: &resource->lock);
350
351 return sprintf(buf, fmt: "%llu\n", resource->power * 1000);
352}
353
354/* Miscellaneous */
355static ssize_t show_str(struct device *dev,
356 struct device_attribute *devattr,
357 char *buf)
358{
359 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
360 struct acpi_device *acpi_dev = to_acpi_device(dev);
361 struct acpi_power_meter_resource *resource = acpi_dev->driver_data;
362 acpi_string val;
363 int ret;
364
365 mutex_lock(&resource->lock);
366 switch (attr->index) {
367 case 0:
368 val = resource->model_number;
369 break;
370 case 1:
371 val = resource->serial_number;
372 break;
373 case 2:
374 val = resource->oem_info;
375 break;
376 default:
377 WARN(1, "Implementation error: unexpected attribute index %d\n",
378 attr->index);
379 val = "";
380 break;
381 }
382 ret = sprintf(buf, fmt: "%s\n", val);
383 mutex_unlock(lock: &resource->lock);
384 return ret;
385}
386
387static ssize_t show_val(struct device *dev,
388 struct device_attribute *devattr,
389 char *buf)
390{
391 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
392 struct acpi_device *acpi_dev = to_acpi_device(dev);
393 struct acpi_power_meter_resource *resource = acpi_dev->driver_data;
394 u64 val = 0;
395
396 switch (attr->index) {
397 case 0:
398 val = resource->caps.min_avg_interval;
399 break;
400 case 1:
401 val = resource->caps.max_avg_interval;
402 break;
403 case 2:
404 val = resource->caps.min_cap * 1000;
405 break;
406 case 3:
407 val = resource->caps.max_cap * 1000;
408 break;
409 case 4:
410 if (resource->caps.hysteresis == UNKNOWN_HYSTERESIS)
411 return sprintf(buf, fmt: "unknown\n");
412
413 val = resource->caps.hysteresis * 1000;
414 break;
415 case 5:
416 if (resource->caps.flags & POWER_METER_IS_BATTERY)
417 val = 1;
418 else
419 val = 0;
420 break;
421 case 6:
422 if (resource->power > resource->cap)
423 val = 1;
424 else
425 val = 0;
426 break;
427 case 7:
428 case 8:
429 if (resource->trip[attr->index - 7] < 0)
430 return sprintf(buf, fmt: "unknown\n");
431
432 val = resource->trip[attr->index - 7] * 1000;
433 break;
434 default:
435 WARN(1, "Implementation error: unexpected attribute index %d\n",
436 attr->index);
437 break;
438 }
439
440 return sprintf(buf, fmt: "%llu\n", val);
441}
442
443static ssize_t show_accuracy(struct device *dev,
444 struct device_attribute *devattr,
445 char *buf)
446{
447 struct acpi_device *acpi_dev = to_acpi_device(dev);
448 struct acpi_power_meter_resource *resource = acpi_dev->driver_data;
449 unsigned int acc = resource->caps.accuracy;
450
451 return sprintf(buf, fmt: "%u.%u%%\n", acc / 1000, acc % 1000);
452}
453
454static ssize_t show_name(struct device *dev,
455 struct device_attribute *devattr,
456 char *buf)
457{
458 return sprintf(buf, fmt: "%s\n", ACPI_POWER_METER_NAME);
459}
460
461#define RO_SENSOR_TEMPLATE(_label, _show, _index) \
462 { \
463 .label = _label, \
464 .show = _show, \
465 .index = _index, \
466 }
467
468#define RW_SENSOR_TEMPLATE(_label, _show, _set, _index) \
469 { \
470 .label = _label, \
471 .show = _show, \
472 .set = _set, \
473 .index = _index, \
474 }
475
476/* Sensor descriptions. If you add a sensor, update NUM_SENSORS above! */
477static struct sensor_template meter_attrs[] = {
478 RO_SENSOR_TEMPLATE(POWER_AVERAGE_NAME, show_power, 0),
479 RO_SENSOR_TEMPLATE("power1_accuracy", show_accuracy, 0),
480 RO_SENSOR_TEMPLATE("power1_average_interval_min", show_val, 0),
481 RO_SENSOR_TEMPLATE("power1_average_interval_max", show_val, 1),
482 RO_SENSOR_TEMPLATE("power1_is_battery", show_val, 5),
483 RW_SENSOR_TEMPLATE(POWER_AVG_INTERVAL_NAME, show_avg_interval,
484 set_avg_interval, 0),
485 {},
486};
487
488static struct sensor_template misc_cap_attrs[] = {
489 RO_SENSOR_TEMPLATE("power1_cap_min", show_val, 2),
490 RO_SENSOR_TEMPLATE("power1_cap_max", show_val, 3),
491 RO_SENSOR_TEMPLATE("power1_cap_hyst", show_val, 4),
492 RO_SENSOR_TEMPLATE(POWER_ALARM_NAME, show_val, 6),
493 {},
494};
495
496static struct sensor_template ro_cap_attrs[] = {
497 RO_SENSOR_TEMPLATE(POWER_CAP_NAME, show_cap, 0),
498 {},
499};
500
501static struct sensor_template rw_cap_attrs[] = {
502 RW_SENSOR_TEMPLATE(POWER_CAP_NAME, show_cap, set_cap, 0),
503 {},
504};
505
506static struct sensor_template trip_attrs[] = {
507 RW_SENSOR_TEMPLATE("power1_average_min", show_val, set_trip, 7),
508 RW_SENSOR_TEMPLATE("power1_average_max", show_val, set_trip, 8),
509 {},
510};
511
512static struct sensor_template misc_attrs[] = {
513 RO_SENSOR_TEMPLATE("name", show_name, 0),
514 RO_SENSOR_TEMPLATE("power1_model_number", show_str, 0),
515 RO_SENSOR_TEMPLATE("power1_oem_info", show_str, 2),
516 RO_SENSOR_TEMPLATE("power1_serial_number", show_str, 1),
517 {},
518};
519
520#undef RO_SENSOR_TEMPLATE
521#undef RW_SENSOR_TEMPLATE
522
523/* Read power domain data */
524static void remove_domain_devices(struct acpi_power_meter_resource *resource)
525{
526 int i;
527
528 if (!resource->num_domain_devices)
529 return;
530
531 for (i = 0; i < resource->num_domain_devices; i++) {
532 struct acpi_device *obj = resource->domain_devices[i];
533
534 if (!obj)
535 continue;
536
537 sysfs_remove_link(kobj: resource->holders_dir,
538 name: kobject_name(kobj: &obj->dev.kobj));
539 acpi_dev_put(adev: obj);
540 }
541
542 kfree(objp: resource->domain_devices);
543 kobject_put(kobj: resource->holders_dir);
544 resource->num_domain_devices = 0;
545}
546
547static int read_domain_devices(struct acpi_power_meter_resource *resource)
548{
549 int res = 0;
550 int i;
551 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
552 union acpi_object *pss;
553 acpi_status status;
554
555 status = acpi_evaluate_object(object: resource->acpi_dev->handle, pathname: "_PMD", NULL,
556 return_object_buffer: &buffer);
557 if (ACPI_FAILURE(status)) {
558 acpi_evaluation_failure_warn(handle: resource->acpi_dev->handle, name: "_PMD",
559 status);
560 return -ENODEV;
561 }
562
563 pss = buffer.pointer;
564 if (!pss ||
565 pss->type != ACPI_TYPE_PACKAGE) {
566 dev_err(&resource->acpi_dev->dev, ACPI_POWER_METER_NAME
567 "Invalid _PMD data\n");
568 res = -EFAULT;
569 goto end;
570 }
571
572 if (!pss->package.count)
573 goto end;
574
575 resource->domain_devices = kcalloc(n: pss->package.count,
576 size: sizeof(struct acpi_device *),
577 GFP_KERNEL);
578 if (!resource->domain_devices) {
579 res = -ENOMEM;
580 goto end;
581 }
582
583 resource->holders_dir = kobject_create_and_add(name: "measures",
584 parent: &resource->acpi_dev->dev.kobj);
585 if (!resource->holders_dir) {
586 res = -ENOMEM;
587 goto exit_free;
588 }
589
590 resource->num_domain_devices = pss->package.count;
591
592 for (i = 0; i < pss->package.count; i++) {
593 struct acpi_device *obj;
594 union acpi_object *element = &pss->package.elements[i];
595
596 /* Refuse non-references */
597 if (element->type != ACPI_TYPE_LOCAL_REFERENCE)
598 continue;
599
600 /* Create a symlink to domain objects */
601 obj = acpi_get_acpi_dev(handle: element->reference.handle);
602 resource->domain_devices[i] = obj;
603 if (!obj)
604 continue;
605
606 res = sysfs_create_link(kobj: resource->holders_dir, target: &obj->dev.kobj,
607 name: kobject_name(kobj: &obj->dev.kobj));
608 if (res) {
609 acpi_dev_put(adev: obj);
610 resource->domain_devices[i] = NULL;
611 }
612 }
613
614 res = 0;
615 goto end;
616
617exit_free:
618 kfree(objp: resource->domain_devices);
619end:
620 kfree(objp: buffer.pointer);
621 return res;
622}
623
624/* Registration and deregistration */
625static int register_attrs(struct acpi_power_meter_resource *resource,
626 struct sensor_template *attrs)
627{
628 struct device *dev = &resource->acpi_dev->dev;
629 struct sensor_device_attribute *sensors =
630 &resource->sensors[resource->num_sensors];
631 int res = 0;
632
633 while (attrs->label) {
634 sensors->dev_attr.attr.name = attrs->label;
635 sensors->dev_attr.attr.mode = 0444;
636 sensors->dev_attr.show = attrs->show;
637 sensors->index = attrs->index;
638
639 if (attrs->set) {
640 sensors->dev_attr.attr.mode |= 0200;
641 sensors->dev_attr.store = attrs->set;
642 }
643
644 sysfs_attr_init(&sensors->dev_attr.attr);
645 res = device_create_file(device: dev, entry: &sensors->dev_attr);
646 if (res) {
647 sensors->dev_attr.attr.name = NULL;
648 goto error;
649 }
650 sensors++;
651 resource->num_sensors++;
652 attrs++;
653 }
654
655error:
656 return res;
657}
658
659static void remove_attrs(struct acpi_power_meter_resource *resource)
660{
661 int i;
662
663 for (i = 0; i < resource->num_sensors; i++) {
664 if (!resource->sensors[i].dev_attr.attr.name)
665 continue;
666 device_remove_file(dev: &resource->acpi_dev->dev,
667 attr: &resource->sensors[i].dev_attr);
668 }
669
670 remove_domain_devices(resource);
671
672 resource->num_sensors = 0;
673}
674
675static int setup_attrs(struct acpi_power_meter_resource *resource)
676{
677 int res = 0;
678
679 res = read_domain_devices(resource);
680 if (res)
681 return res;
682
683 if (resource->caps.flags & POWER_METER_CAN_MEASURE) {
684 res = register_attrs(resource, attrs: meter_attrs);
685 if (res)
686 goto error;
687 }
688
689 if (resource->caps.flags & POWER_METER_CAN_CAP) {
690 if (!can_cap_in_hardware()) {
691 dev_warn(&resource->acpi_dev->dev,
692 "Ignoring unsafe software power cap!\n");
693 goto skip_unsafe_cap;
694 }
695
696 if (resource->caps.configurable_cap)
697 res = register_attrs(resource, attrs: rw_cap_attrs);
698 else
699 res = register_attrs(resource, attrs: ro_cap_attrs);
700
701 if (res)
702 goto error;
703
704 res = register_attrs(resource, attrs: misc_cap_attrs);
705 if (res)
706 goto error;
707 }
708
709skip_unsafe_cap:
710 if (resource->caps.flags & POWER_METER_CAN_TRIP) {
711 res = register_attrs(resource, attrs: trip_attrs);
712 if (res)
713 goto error;
714 }
715
716 res = register_attrs(resource, attrs: misc_attrs);
717 if (res)
718 goto error;
719
720 return res;
721error:
722 remove_attrs(resource);
723 return res;
724}
725
726static void free_capabilities(struct acpi_power_meter_resource *resource)
727{
728 acpi_string *str;
729 int i;
730
731 str = &resource->model_number;
732 for (i = 0; i < 3; i++, str++) {
733 kfree(objp: *str);
734 *str = NULL;
735 }
736}
737
738static int read_capabilities(struct acpi_power_meter_resource *resource)
739{
740 int res = 0;
741 int i;
742 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
743 struct acpi_buffer state = { 0, NULL };
744 struct acpi_buffer format = { sizeof("NNNNNNNNNNN"), "NNNNNNNNNNN" };
745 union acpi_object *pss;
746 acpi_string *str;
747 acpi_status status;
748
749 status = acpi_evaluate_object(object: resource->acpi_dev->handle, pathname: "_PMC", NULL,
750 return_object_buffer: &buffer);
751 if (ACPI_FAILURE(status)) {
752 acpi_evaluation_failure_warn(handle: resource->acpi_dev->handle, name: "_PMC",
753 status);
754 return -ENODEV;
755 }
756
757 pss = buffer.pointer;
758 if (!pss ||
759 pss->type != ACPI_TYPE_PACKAGE ||
760 pss->package.count != 14) {
761 dev_err(&resource->acpi_dev->dev, ACPI_POWER_METER_NAME
762 "Invalid _PMC data\n");
763 res = -EFAULT;
764 goto end;
765 }
766
767 /* Grab all the integer data at once */
768 state.length = sizeof(struct acpi_power_meter_capabilities);
769 state.pointer = &resource->caps;
770
771 status = acpi_extract_package(package: pss, format: &format, buffer: &state);
772 if (ACPI_FAILURE(status)) {
773 dev_err(&resource->acpi_dev->dev, ACPI_POWER_METER_NAME
774 "_PMC package parsing failed: %s\n",
775 acpi_format_exception(status));
776 res = -EFAULT;
777 goto end;
778 }
779
780 if (resource->caps.units) {
781 dev_err(&resource->acpi_dev->dev, ACPI_POWER_METER_NAME
782 "Unknown units %llu.\n",
783 resource->caps.units);
784 res = -EINVAL;
785 goto end;
786 }
787
788 /* Grab the string data */
789 str = &resource->model_number;
790
791 for (i = 11; i < 14; i++) {
792 union acpi_object *element = &pss->package.elements[i];
793
794 if (element->type != ACPI_TYPE_STRING) {
795 res = -EINVAL;
796 goto error;
797 }
798
799 *str = kmemdup_nul(s: element->string.pointer, len: element->string.length,
800 GFP_KERNEL);
801 if (!*str) {
802 res = -ENOMEM;
803 goto error;
804 }
805
806 str++;
807 }
808
809 dev_info(&resource->acpi_dev->dev, "Found ACPI power meter.\n");
810 goto end;
811error:
812 free_capabilities(resource);
813end:
814 kfree(objp: buffer.pointer);
815 return res;
816}
817
818/* Handle ACPI event notifications */
819static void acpi_power_meter_notify(struct acpi_device *device, u32 event)
820{
821 struct acpi_power_meter_resource *resource;
822 int res;
823
824 if (!device || !acpi_driver_data(d: device))
825 return;
826
827 resource = acpi_driver_data(d: device);
828
829 switch (event) {
830 case METER_NOTIFY_CONFIG:
831 mutex_lock(&resource->lock);
832 free_capabilities(resource);
833 res = read_capabilities(resource);
834 mutex_unlock(lock: &resource->lock);
835 if (res)
836 break;
837
838 remove_attrs(resource);
839 setup_attrs(resource);
840 break;
841 case METER_NOTIFY_TRIP:
842 sysfs_notify(kobj: &device->dev.kobj, NULL, POWER_AVERAGE_NAME);
843 break;
844 case METER_NOTIFY_CAP:
845 sysfs_notify(kobj: &device->dev.kobj, NULL, POWER_CAP_NAME);
846 break;
847 case METER_NOTIFY_INTERVAL:
848 sysfs_notify(kobj: &device->dev.kobj, NULL, POWER_AVG_INTERVAL_NAME);
849 break;
850 case METER_NOTIFY_CAPPING:
851 sysfs_notify(kobj: &device->dev.kobj, NULL, POWER_ALARM_NAME);
852 dev_info(&device->dev, "Capping in progress.\n");
853 break;
854 default:
855 WARN(1, "Unexpected event %d\n", event);
856 break;
857 }
858
859 acpi_bus_generate_netlink_event(ACPI_POWER_METER_CLASS,
860 dev_name(dev: &device->dev), event, 0);
861}
862
863static int acpi_power_meter_add(struct acpi_device *device)
864{
865 int res;
866 struct acpi_power_meter_resource *resource;
867
868 if (!device)
869 return -EINVAL;
870
871 resource = kzalloc(size: sizeof(*resource), GFP_KERNEL);
872 if (!resource)
873 return -ENOMEM;
874
875 resource->sensors_valid = 0;
876 resource->acpi_dev = device;
877 mutex_init(&resource->lock);
878 strcpy(acpi_device_name(device), ACPI_POWER_METER_DEVICE_NAME);
879 strcpy(acpi_device_class(device), ACPI_POWER_METER_CLASS);
880 device->driver_data = resource;
881
882 res = read_capabilities(resource);
883 if (res)
884 goto exit_free;
885
886 resource->trip[0] = -1;
887 resource->trip[1] = -1;
888
889 res = setup_attrs(resource);
890 if (res)
891 goto exit_free_capability;
892
893 resource->hwmon_dev = hwmon_device_register(dev: &device->dev);
894 if (IS_ERR(ptr: resource->hwmon_dev)) {
895 res = PTR_ERR(ptr: resource->hwmon_dev);
896 goto exit_remove;
897 }
898
899 res = 0;
900 goto exit;
901
902exit_remove:
903 remove_attrs(resource);
904exit_free_capability:
905 free_capabilities(resource);
906exit_free:
907 kfree(objp: resource);
908exit:
909 return res;
910}
911
912static void acpi_power_meter_remove(struct acpi_device *device)
913{
914 struct acpi_power_meter_resource *resource;
915
916 if (!device || !acpi_driver_data(d: device))
917 return;
918
919 resource = acpi_driver_data(d: device);
920 hwmon_device_unregister(dev: resource->hwmon_dev);
921
922 remove_attrs(resource);
923 free_capabilities(resource);
924
925 kfree(objp: resource);
926}
927
928static int acpi_power_meter_resume(struct device *dev)
929{
930 struct acpi_power_meter_resource *resource;
931
932 if (!dev)
933 return -EINVAL;
934
935 resource = acpi_driver_data(to_acpi_device(dev));
936 if (!resource)
937 return -EINVAL;
938
939 free_capabilities(resource);
940 read_capabilities(resource);
941
942 return 0;
943}
944
945static DEFINE_SIMPLE_DEV_PM_OPS(acpi_power_meter_pm, NULL,
946 acpi_power_meter_resume);
947
948static struct acpi_driver acpi_power_meter_driver = {
949 .name = "power_meter",
950 .class = ACPI_POWER_METER_CLASS,
951 .ids = power_meter_ids,
952 .ops = {
953 .add = acpi_power_meter_add,
954 .remove = acpi_power_meter_remove,
955 .notify = acpi_power_meter_notify,
956 },
957 .drv.pm = pm_sleep_ptr(&acpi_power_meter_pm),
958};
959
960/* Module init/exit routines */
961static int __init enable_cap_knobs(const struct dmi_system_id *d)
962{
963 cap_in_hardware = 1;
964 return 0;
965}
966
967static const struct dmi_system_id pm_dmi_table[] __initconst = {
968 {
969 enable_cap_knobs, "IBM Active Energy Manager",
970 {
971 DMI_MATCH(DMI_SYS_VENDOR, "IBM")
972 },
973 },
974 {}
975};
976
977static int __init acpi_power_meter_init(void)
978{
979 int result;
980
981 if (acpi_disabled)
982 return -ENODEV;
983
984 dmi_check_system(list: pm_dmi_table);
985
986 result = acpi_bus_register_driver(driver: &acpi_power_meter_driver);
987 if (result < 0)
988 return result;
989
990 return 0;
991}
992
993static void __exit acpi_power_meter_exit(void)
994{
995 acpi_bus_unregister_driver(driver: &acpi_power_meter_driver);
996}
997
998MODULE_AUTHOR("Darrick J. Wong <darrick.wong@oracle.com>");
999MODULE_DESCRIPTION("ACPI 4.0 power meter driver");
1000MODULE_LICENSE("GPL");
1001
1002module_param(force_cap_on, bool, 0644);
1003MODULE_PARM_DESC(force_cap_on, "Enable power cap even it is unsafe to do so.");
1004
1005module_init(acpi_power_meter_init);
1006module_exit(acpi_power_meter_exit);
1007

source code of linux/drivers/hwmon/acpi_power_meter.c