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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * drivers/acpi/device_sysfs.c - ACPI device sysfs attributes and modalias.
4 *
5 * Copyright (C) 2015, Intel Corp.
6 * Author: Mika Westerberg <mika.westerberg@linux.intel.com>
7 * Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
8 *
9 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
10 *
11 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
12 */
13
14#include <linux/acpi.h>
15#include <linux/device.h>
16#include <linux/export.h>
17#include <linux/nls.h>
18
19#include "internal.h"
20
21static ssize_t acpi_object_path(acpi_handle handle, char *buf)
22{
23 struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
24 int result;
25
26 result = acpi_get_name(handle, ACPI_FULL_PATHNAME, &path);
27 if (result)
28 return result;
29
30 result = sprintf(buf, "%s\n", (char *)path.pointer);
31 kfree(path.pointer);
32 return result;
33}
34
35struct acpi_data_node_attr {
36 struct attribute attr;
37 ssize_t (*show)(struct acpi_data_node *, char *);
38 ssize_t (*store)(struct acpi_data_node *, const char *, size_t count);
39};
40
41#define DATA_NODE_ATTR(_name) \
42 static struct acpi_data_node_attr data_node_##_name = \
43 __ATTR(_name, 0444, data_node_show_##_name, NULL)
44
45static ssize_t data_node_show_path(struct acpi_data_node *dn, char *buf)
46{
47 return dn->handle ? acpi_object_path(dn->handle, buf) : 0;
48}
49
50DATA_NODE_ATTR(path);
51
52static struct attribute *acpi_data_node_default_attrs[] = {
53 &data_node_path.attr,
54 NULL
55};
56
57#define to_data_node(k) container_of(k, struct acpi_data_node, kobj)
58#define to_attr(a) container_of(a, struct acpi_data_node_attr, attr)
59
60static ssize_t acpi_data_node_attr_show(struct kobject *kobj,
61 struct attribute *attr, char *buf)
62{
63 struct acpi_data_node *dn = to_data_node(kobj);
64 struct acpi_data_node_attr *dn_attr = to_attr(attr);
65
66 return dn_attr->show ? dn_attr->show(dn, buf) : -ENXIO;
67}
68
69static const struct sysfs_ops acpi_data_node_sysfs_ops = {
70 .show = acpi_data_node_attr_show,
71};
72
73static void acpi_data_node_release(struct kobject *kobj)
74{
75 struct acpi_data_node *dn = to_data_node(kobj);
76
77 complete(&dn->kobj_done);
78}
79
80static struct kobj_type acpi_data_node_ktype = {
81 .sysfs_ops = &acpi_data_node_sysfs_ops,
82 .default_attrs = acpi_data_node_default_attrs,
83 .release = acpi_data_node_release,
84};
85
86static void acpi_expose_nondev_subnodes(struct kobject *kobj,
87 struct acpi_device_data *data)
88{
89 struct list_head *list = &data->subnodes;
90 struct acpi_data_node *dn;
91
92 if (list_empty(list))
93 return;
94
95 list_for_each_entry(dn, list, sibling) {
96 int ret;
97
98 init_completion(&dn->kobj_done);
99 ret = kobject_init_and_add(&dn->kobj, &acpi_data_node_ktype,
100 kobj, "%s", dn->name);
101 if (!ret)
102 acpi_expose_nondev_subnodes(&dn->kobj, &dn->data);
103 else if (dn->handle)
104 acpi_handle_err(dn->handle, "Failed to expose (%d)\n", ret);
105 }
106}
107
108static void acpi_hide_nondev_subnodes(struct acpi_device_data *data)
109{
110 struct list_head *list = &data->subnodes;
111 struct acpi_data_node *dn;
112
113 if (list_empty(list))
114 return;
115
116 list_for_each_entry_reverse(dn, list, sibling) {
117 acpi_hide_nondev_subnodes(&dn->data);
118 kobject_put(&dn->kobj);
119 }
120}
121
122/**
123 * create_pnp_modalias - Create hid/cid(s) string for modalias and uevent
124 * @acpi_dev: ACPI device object.
125 * @modalias: Buffer to print into.
126 * @size: Size of the buffer.
127 *
128 * Creates hid/cid(s) string needed for modalias and uevent
129 * e.g. on a device with hid:IBM0001 and cid:ACPI0001 you get:
130 * char *modalias: "acpi:IBM0001:ACPI0001"
131 * Return: 0: no _HID and no _CID
132 * -EINVAL: output error
133 * -ENOMEM: output is truncated
134 */
135static int create_pnp_modalias(struct acpi_device *acpi_dev, char *modalias,
136 int size)
137{
138 int len;
139 int count;
140 struct acpi_hardware_id *id;
141
142 /* Avoid unnecessarily loading modules for non present devices. */
143 if (!acpi_device_is_present(acpi_dev))
144 return 0;
145
146 /*
147 * Since we skip ACPI_DT_NAMESPACE_HID from the modalias below, 0 should
148 * be returned if ACPI_DT_NAMESPACE_HID is the only ACPI/PNP ID in the
149 * device's list.
150 */
151 count = 0;
152 list_for_each_entry(id, &acpi_dev->pnp.ids, list)
153 if (strcmp(id->id, ACPI_DT_NAMESPACE_HID))
154 count++;
155
156 if (!count)
157 return 0;
158
159 len = snprintf(modalias, size, "acpi:");
160 if (len <= 0)
161 return len;
162
163 size -= len;
164
165 list_for_each_entry(id, &acpi_dev->pnp.ids, list) {
166 if (!strcmp(id->id, ACPI_DT_NAMESPACE_HID))
167 continue;
168
169 count = snprintf(&modalias[len], size, "%s:", id->id);
170 if (count < 0)
171 return -EINVAL;
172
173 if (count >= size)
174 return -ENOMEM;
175
176 len += count;
177 size -= count;
178 }
179 modalias[len] = '\0';
180 return len;
181}
182
183/**
184 * create_of_modalias - Creates DT compatible string for modalias and uevent
185 * @acpi_dev: ACPI device object.
186 * @modalias: Buffer to print into.
187 * @size: Size of the buffer.
188 *
189 * Expose DT compatible modalias as of:NnameTCcompatible. This function should
190 * only be called for devices having ACPI_DT_NAMESPACE_HID in their list of
191 * ACPI/PNP IDs.
192 */
193static int create_of_modalias(struct acpi_device *acpi_dev, char *modalias,
194 int size)
195{
196 struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER };
197 const union acpi_object *of_compatible, *obj;
198 acpi_status status;
199 int len, count;
200 int i, nval;
201 char *c;
202
203 status = acpi_get_name(acpi_dev->handle, ACPI_SINGLE_NAME, &buf);
204 if (ACPI_FAILURE(status))
205 return -ENODEV;
206
207 /* DT strings are all in lower case */
208 for (c = buf.pointer; *c != '\0'; c++)
209 *c = tolower(*c);
210
211 len = snprintf(modalias, size, "of:N%sT", (char *)buf.pointer);
212 ACPI_FREE(buf.pointer);
213
214 if (len <= 0)
215 return len;
216
217 of_compatible = acpi_dev->data.of_compatible;
218 if (of_compatible->type == ACPI_TYPE_PACKAGE) {
219 nval = of_compatible->package.count;
220 obj = of_compatible->package.elements;
221 } else { /* Must be ACPI_TYPE_STRING. */
222 nval = 1;
223 obj = of_compatible;
224 }
225 for (i = 0; i < nval; i++, obj++) {
226 count = snprintf(&modalias[len], size, "C%s",
227 obj->string.pointer);
228 if (count < 0)
229 return -EINVAL;
230
231 if (count >= size)
232 return -ENOMEM;
233
234 len += count;
235 size -= count;
236 }
237 modalias[len] = '\0';
238 return len;
239}
240
241int __acpi_device_uevent_modalias(struct acpi_device *adev,
242 struct kobj_uevent_env *env)
243{
244 int len;
245
246 if (!adev)
247 return -ENODEV;
248
249 if (list_empty(&adev->pnp.ids))
250 return 0;
251
252 if (add_uevent_var(env, "MODALIAS="))
253 return -ENOMEM;
254
255 if (adev->data.of_compatible)
256 len = create_of_modalias(adev, &env->buf[env->buflen - 1],
257 sizeof(env->buf) - env->buflen);
258 else
259 len = create_pnp_modalias(adev, &env->buf[env->buflen - 1],
260 sizeof(env->buf) - env->buflen);
261 if (len < 0)
262 return len;
263
264 env->buflen += len;
265
266 return 0;
267}
268
269/**
270 * acpi_device_uevent_modalias - uevent modalias for ACPI-enumerated devices.
271 * @dev: Struct device to get ACPI device node.
272 * @env: Environment variables of the kobject uevent.
273 *
274 * Create the uevent modalias field for ACPI-enumerated devices.
275 *
276 * Because other buses do not support ACPI HIDs & CIDs, e.g. for a device with
277 * hid:IBM0001 and cid:ACPI0001 you get: "acpi:IBM0001:ACPI0001".
278 */
279int acpi_device_uevent_modalias(struct device *dev, struct kobj_uevent_env *env)
280{
281 return __acpi_device_uevent_modalias(acpi_companion_match(dev), env);
282}
283EXPORT_SYMBOL_GPL(acpi_device_uevent_modalias);
284
285static int __acpi_device_modalias(struct acpi_device *adev, char *buf, int size)
286{
287 int len, count;
288
289 if (!adev)
290 return -ENODEV;
291
292 if (list_empty(&adev->pnp.ids))
293 return 0;
294
295 len = create_pnp_modalias(adev, buf, size - 1);
296 if (len < 0) {
297 return len;
298 } else if (len > 0) {
299 buf[len++] = '\n';
300 size -= len;
301 }
302 if (!adev->data.of_compatible)
303 return len;
304
305 count = create_of_modalias(adev, buf + len, size - 1);
306 if (count < 0) {
307 return count;
308 } else if (count > 0) {
309 len += count;
310 buf[len++] = '\n';
311 }
312
313 return len;
314}
315
316/**
317 * acpi_device_modalias - modalias sysfs attribute for ACPI-enumerated devices.
318 * @dev: Struct device to get ACPI device node.
319 * @buf: The buffer to save pnp_modalias and of_modalias.
320 * @size: Size of buffer.
321 *
322 * Create the modalias sysfs attribute for ACPI-enumerated devices.
323 *
324 * Because other buses do not support ACPI HIDs & CIDs, e.g. for a device with
325 * hid:IBM0001 and cid:ACPI0001 you get: "acpi:IBM0001:ACPI0001".
326 */
327int acpi_device_modalias(struct device *dev, char *buf, int size)
328{
329 return __acpi_device_modalias(acpi_companion_match(dev), buf, size);
330}
331EXPORT_SYMBOL_GPL(acpi_device_modalias);
332
333static ssize_t
334modalias_show(struct device *dev, struct device_attribute *attr, char *buf)
335{
336 return __acpi_device_modalias(to_acpi_device(dev), buf, 1024);
337}
338static DEVICE_ATTR_RO(modalias);
339
340static ssize_t real_power_state_show(struct device *dev,
341 struct device_attribute *attr, char *buf)
342{
343 struct acpi_device *adev = to_acpi_device(dev);
344 int state;
345 int ret;
346
347 ret = acpi_device_get_power(adev, &state);
348 if (ret)
349 return ret;
350
351 return sprintf(buf, "%s\n", acpi_power_state_string(state));
352}
353
354static DEVICE_ATTR_RO(real_power_state);
355
356static ssize_t power_state_show(struct device *dev,
357 struct device_attribute *attr, char *buf)
358{
359 struct acpi_device *adev = to_acpi_device(dev);
360
361 return sprintf(buf, "%s\n", acpi_power_state_string(adev->power.state));
362}
363
364static DEVICE_ATTR_RO(power_state);
365
366static ssize_t
367eject_store(struct device *d, struct device_attribute *attr,
368 const char *buf, size_t count)
369{
370 struct acpi_device *acpi_device = to_acpi_device(d);
371 acpi_object_type not_used;
372 acpi_status status;
373
374 if (!count || buf[0] != '1')
375 return -EINVAL;
376
377 if ((!acpi_device->handler || !acpi_device->handler->hotplug.enabled)
378 && !acpi_device->driver)
379 return -ENODEV;
380
381 status = acpi_get_type(acpi_device->handle, ¬_used);
382 if (ACPI_FAILURE(status) || !acpi_device->flags.ejectable)
383 return -ENODEV;
384
385 acpi_dev_get(acpi_device);
386 status = acpi_hotplug_schedule(acpi_device, ACPI_OST_EC_OSPM_EJECT);
387 if (ACPI_SUCCESS(status))
388 return count;
389
390 acpi_dev_put(acpi_device);
391 acpi_evaluate_ost(acpi_device->handle, ACPI_OST_EC_OSPM_EJECT,
392 ACPI_OST_SC_NON_SPECIFIC_FAILURE, NULL);
393 return status == AE_NO_MEMORY ? -ENOMEM : -EAGAIN;
394}
395
396static DEVICE_ATTR_WO(eject);
397
398static ssize_t
399hid_show(struct device *dev, struct device_attribute *attr, char *buf)
400{
401 struct acpi_device *acpi_dev = to_acpi_device(dev);
402
403 return sprintf(buf, "%s\n", acpi_device_hid(acpi_dev));
404}
405static DEVICE_ATTR_RO(hid);
406
407static ssize_t uid_show(struct device *dev,
408 struct device_attribute *attr, char *buf)
409{
410 struct acpi_device *acpi_dev = to_acpi_device(dev);
411
412 return sprintf(buf, "%s\n", acpi_dev->pnp.unique_id);
413}
414static DEVICE_ATTR_RO(uid);
415
416static ssize_t adr_show(struct device *dev,
417 struct device_attribute *attr, char *buf)
418{
419 struct acpi_device *acpi_dev = to_acpi_device(dev);
420
421 if (acpi_dev->pnp.bus_address > U32_MAX)
422 return sprintf(buf, "0x%016llx\n", acpi_dev->pnp.bus_address);
423 else
424 return sprintf(buf, "0x%08llx\n", acpi_dev->pnp.bus_address);
425}
426static DEVICE_ATTR_RO(adr);
427
428static ssize_t path_show(struct device *dev,
429 struct device_attribute *attr, char *buf)
430{
431 struct acpi_device *acpi_dev = to_acpi_device(dev);
432
433 return acpi_object_path(acpi_dev->handle, buf);
434}
435static DEVICE_ATTR_RO(path);
436
437/* sysfs file that shows description text from the ACPI _STR method */
438static ssize_t description_show(struct device *dev,
439 struct device_attribute *attr,
440 char *buf)
441{
442 struct acpi_device *acpi_dev = to_acpi_device(dev);
443 int result;
444
445 if (acpi_dev->pnp.str_obj == NULL)
446 return 0;
447
448 /*
449 * The _STR object contains a Unicode identifier for a device.
450 * We need to convert to utf-8 so it can be displayed.
451 */
452 result = utf16s_to_utf8s(
453 (wchar_t *)acpi_dev->pnp.str_obj->buffer.pointer,
454 acpi_dev->pnp.str_obj->buffer.length,
455 UTF16_LITTLE_ENDIAN, buf,
456 PAGE_SIZE - 1);
457
458 buf[result++] = '\n';
459
460 return result;
461}
462static DEVICE_ATTR_RO(description);
463
464static ssize_t
465sun_show(struct device *dev, struct device_attribute *attr,
466 char *buf)
467{
468 struct acpi_device *acpi_dev = to_acpi_device(dev);
469 acpi_status status;
470 unsigned long long sun;
471
472 status = acpi_evaluate_integer(acpi_dev->handle, "_SUN", NULL, &sun);
473 if (ACPI_FAILURE(status))
474 return -EIO;
475
476 return sprintf(buf, "%llu\n", sun);
477}
478static DEVICE_ATTR_RO(sun);
479
480static ssize_t
481hrv_show(struct device *dev, struct device_attribute *attr,
482 char *buf)
483{
484 struct acpi_device *acpi_dev = to_acpi_device(dev);
485 acpi_status status;
486 unsigned long long hrv;
487
488 status = acpi_evaluate_integer(acpi_dev->handle, "_HRV", NULL, &hrv);
489 if (ACPI_FAILURE(status))
490 return -EIO;
491
492 return sprintf(buf, "%llu\n", hrv);
493}
494static DEVICE_ATTR_RO(hrv);
495
496static ssize_t status_show(struct device *dev, struct device_attribute *attr,
497 char *buf)
498{
499 struct acpi_device *acpi_dev = to_acpi_device(dev);
500 acpi_status status;
501 unsigned long long sta;
502
503 status = acpi_evaluate_integer(acpi_dev->handle, "_STA", NULL, &sta);
504 if (ACPI_FAILURE(status))
505 return -EIO;
506
507 return sprintf(buf, "%llu\n", sta);
508}
509static DEVICE_ATTR_RO(status);
510
511/**
512 * acpi_device_setup_files - Create sysfs attributes of an ACPI device.
513 * @dev: ACPI device object.
514 */
515int acpi_device_setup_files(struct acpi_device *dev)
516{
517 struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
518 acpi_status status;
519 int result = 0;
520
521 /*
522 * Devices gotten from FADT don't have a "path" attribute
523 */
524 if (dev->handle) {
525 result = device_create_file(&dev->dev, &dev_attr_path);
526 if (result)
527 goto end;
528 }
529
530 if (!list_empty(&dev->pnp.ids)) {
531 result = device_create_file(&dev->dev, &dev_attr_hid);
532 if (result)
533 goto end;
534
535 result = device_create_file(&dev->dev, &dev_attr_modalias);
536 if (result)
537 goto end;
538 }
539
540 /*
541 * If device has _STR, 'description' file is created
542 */
543 if (acpi_has_method(dev->handle, "_STR")) {
544 status = acpi_evaluate_object(dev->handle, "_STR",
545 NULL, &buffer);
546 if (ACPI_FAILURE(status))
547 buffer.pointer = NULL;
548 dev->pnp.str_obj = buffer.pointer;
549 result = device_create_file(&dev->dev, &dev_attr_description);
550 if (result)
551 goto end;
552 }
553
554 if (dev->pnp.type.bus_address)
555 result = device_create_file(&dev->dev, &dev_attr_adr);
556 if (dev->pnp.unique_id)
557 result = device_create_file(&dev->dev, &dev_attr_uid);
558
559 if (acpi_has_method(dev->handle, "_SUN")) {
560 result = device_create_file(&dev->dev, &dev_attr_sun);
561 if (result)
562 goto end;
563 }
564
565 if (acpi_has_method(dev->handle, "_HRV")) {
566 result = device_create_file(&dev->dev, &dev_attr_hrv);
567 if (result)
568 goto end;
569 }
570
571 if (acpi_has_method(dev->handle, "_STA")) {
572 result = device_create_file(&dev->dev, &dev_attr_status);
573 if (result)
574 goto end;
575 }
576
577 /*
578 * If device has _EJ0, 'eject' file is created that is used to trigger
579 * hot-removal function from userland.
580 */
581 if (acpi_has_method(dev->handle, "_EJ0")) {
582 result = device_create_file(&dev->dev, &dev_attr_eject);
583 if (result)
584 return result;
585 }
586
587 if (dev->flags.power_manageable) {
588 result = device_create_file(&dev->dev, &dev_attr_power_state);
589 if (result)
590 return result;
591
592 if (dev->power.flags.power_resources)
593 result = device_create_file(&dev->dev,
594 &dev_attr_real_power_state);
595 }
596
597 acpi_expose_nondev_subnodes(&dev->dev.kobj, &dev->data);
598
599end:
600 return result;
601}
602
603/**
604 * acpi_device_remove_files - Remove sysfs attributes of an ACPI device.
605 * @dev: ACPI device object.
606 */
607void acpi_device_remove_files(struct acpi_device *dev)
608{
609 acpi_hide_nondev_subnodes(&dev->data);
610
611 if (dev->flags.power_manageable) {
612 device_remove_file(&dev->dev, &dev_attr_power_state);
613 if (dev->power.flags.power_resources)
614 device_remove_file(&dev->dev,
615 &dev_attr_real_power_state);
616 }
617
618 /*
619 * If device has _STR, remove 'description' file
620 */
621 if (acpi_has_method(dev->handle, "_STR")) {
622 kfree(dev->pnp.str_obj);
623 device_remove_file(&dev->dev, &dev_attr_description);
624 }
625 /*
626 * If device has _EJ0, remove 'eject' file.
627 */
628 if (acpi_has_method(dev->handle, "_EJ0"))
629 device_remove_file(&dev->dev, &dev_attr_eject);
630
631 if (acpi_has_method(dev->handle, "_SUN"))
632 device_remove_file(&dev->dev, &dev_attr_sun);
633
634 if (acpi_has_method(dev->handle, "_HRV"))
635 device_remove_file(&dev->dev, &dev_attr_hrv);
636
637 if (dev->pnp.unique_id)
638 device_remove_file(&dev->dev, &dev_attr_uid);
639 if (dev->pnp.type.bus_address)
640 device_remove_file(&dev->dev, &dev_attr_adr);
641 device_remove_file(&dev->dev, &dev_attr_modalias);
642 device_remove_file(&dev->dev, &dev_attr_hid);
643 if (acpi_has_method(dev->handle, "_STA"))
644 device_remove_file(&dev->dev, &dev_attr_status);
645 if (dev->handle)
646 device_remove_file(&dev->dev, &dev_attr_path);
647}