Merge tag 'armsoc-defconfig' of git://git.kernel.org/pub/scm/linux/kernel/git/arm...
[firefly-linux-kernel-4.4.55.git] / drivers / acpi / device_sysfs.c
1 /*
2  * drivers/acpi/device_sysfs.c - ACPI device sysfs attributes and modalias.
3  *
4  * Copyright (C) 2015, Intel Corp.
5  * Author: Mika Westerberg <mika.westerberg@linux.intel.com>
6  * Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
7  *
8  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
9  *
10  *  This program is free software; you can redistribute it and/or modify
11  *  it under the terms of the GNU General Public License version 2 as published
12  *  by the Free Software Foundation.
13  *
14  *  This program is distributed in the hope that it will be useful, but
15  *  WITHOUT ANY WARRANTY; without even the implied warranty of
16  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17  *  General Public License for more details.
18  *
19  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
20  */
21
22 #include <linux/acpi.h>
23 #include <linux/device.h>
24 #include <linux/export.h>
25 #include <linux/nls.h>
26
27 #include "internal.h"
28
29 static ssize_t acpi_object_path(acpi_handle handle, char *buf)
30 {
31         struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
32         int result;
33
34         result = acpi_get_name(handle, ACPI_FULL_PATHNAME, &path);
35         if (result)
36                 return result;
37
38         result = sprintf(buf, "%s\n", (char*)path.pointer);
39         kfree(path.pointer);
40         return result;
41 }
42
43 struct acpi_data_node_attr {
44         struct attribute attr;
45         ssize_t (*show)(struct acpi_data_node *, char *);
46         ssize_t (*store)(struct acpi_data_node *, const char *, size_t count);
47 };
48
49 #define DATA_NODE_ATTR(_name)                   \
50         static struct acpi_data_node_attr data_node_##_name =   \
51                 __ATTR(_name, 0444, data_node_show_##_name, NULL)
52
53 static ssize_t data_node_show_path(struct acpi_data_node *dn, char *buf)
54 {
55         return acpi_object_path(dn->handle, buf);
56 }
57
58 DATA_NODE_ATTR(path);
59
60 static struct attribute *acpi_data_node_default_attrs[] = {
61         &data_node_path.attr,
62         NULL
63 };
64
65 #define to_data_node(k) container_of(k, struct acpi_data_node, kobj)
66 #define to_attr(a) container_of(a, struct acpi_data_node_attr, attr)
67
68 static ssize_t acpi_data_node_attr_show(struct kobject *kobj,
69                                         struct attribute *attr, char *buf)
70 {
71         struct acpi_data_node *dn = to_data_node(kobj);
72         struct acpi_data_node_attr *dn_attr = to_attr(attr);
73
74         return dn_attr->show ? dn_attr->show(dn, buf) : -ENXIO;
75 }
76
77 static const struct sysfs_ops acpi_data_node_sysfs_ops = {
78         .show   = acpi_data_node_attr_show,
79 };
80
81 static void acpi_data_node_release(struct kobject *kobj)
82 {
83         struct acpi_data_node *dn = to_data_node(kobj);
84         complete(&dn->kobj_done);
85 }
86
87 static struct kobj_type acpi_data_node_ktype = {
88         .sysfs_ops = &acpi_data_node_sysfs_ops,
89         .default_attrs = acpi_data_node_default_attrs,
90         .release = acpi_data_node_release,
91 };
92
93 static void acpi_expose_nondev_subnodes(struct kobject *kobj,
94                                         struct acpi_device_data *data)
95 {
96         struct list_head *list = &data->subnodes;
97         struct acpi_data_node *dn;
98
99         if (list_empty(list))
100                 return;
101
102         list_for_each_entry(dn, list, sibling) {
103                 int ret;
104
105                 init_completion(&dn->kobj_done);
106                 ret = kobject_init_and_add(&dn->kobj, &acpi_data_node_ktype,
107                                            kobj, dn->name);
108                 if (ret)
109                         acpi_handle_err(dn->handle, "Failed to expose (%d)\n", ret);
110                 else
111                         acpi_expose_nondev_subnodes(&dn->kobj, &dn->data);
112         }
113 }
114
115 static void acpi_hide_nondev_subnodes(struct acpi_device_data *data)
116 {
117         struct list_head *list = &data->subnodes;
118         struct acpi_data_node *dn;
119
120         if (list_empty(list))
121                 return;
122
123         list_for_each_entry_reverse(dn, list, sibling) {
124                 acpi_hide_nondev_subnodes(&dn->data);
125                 kobject_put(&dn->kobj);
126         }
127 }
128
129 /**
130  * create_pnp_modalias - Create hid/cid(s) string for modalias and uevent
131  * @acpi_dev: ACPI device object.
132  * @modalias: Buffer to print into.
133  * @size: Size of the buffer.
134  *
135  * Creates hid/cid(s) string needed for modalias and uevent
136  * e.g. on a device with hid:IBM0001 and cid:ACPI0001 you get:
137  * char *modalias: "acpi:IBM0001:ACPI0001"
138  * Return: 0: no _HID and no _CID
139  *         -EINVAL: output error
140  *         -ENOMEM: output is truncated
141 */
142 static int create_pnp_modalias(struct acpi_device *acpi_dev, char *modalias,
143                                int size)
144 {
145         int len;
146         int count;
147         struct acpi_hardware_id *id;
148
149         /*
150          * Since we skip ACPI_DT_NAMESPACE_HID from the modalias below, 0 should
151          * be returned if ACPI_DT_NAMESPACE_HID is the only ACPI/PNP ID in the
152          * device's list.
153          */
154         count = 0;
155         list_for_each_entry(id, &acpi_dev->pnp.ids, list)
156                 if (strcmp(id->id, ACPI_DT_NAMESPACE_HID))
157                         count++;
158
159         if (!count)
160                 return 0;
161
162         len = snprintf(modalias, size, "acpi:");
163         if (len <= 0)
164                 return len;
165
166         size -= len;
167
168         list_for_each_entry(id, &acpi_dev->pnp.ids, list) {
169                 if (!strcmp(id->id, ACPI_DT_NAMESPACE_HID))
170                         continue;
171
172                 count = snprintf(&modalias[len], size, "%s:", id->id);
173                 if (count < 0)
174                         return -EINVAL;
175
176                 if (count >= size)
177                         return -ENOMEM;
178
179                 len += count;
180                 size -= count;
181         }
182         modalias[len] = '\0';
183         return len;
184 }
185
186 /**
187  * create_of_modalias - Creates DT compatible string for modalias and uevent
188  * @acpi_dev: ACPI device object.
189  * @modalias: Buffer to print into.
190  * @size: Size of the buffer.
191  *
192  * Expose DT compatible modalias as of:NnameTCcompatible.  This function should
193  * only be called for devices having ACPI_DT_NAMESPACE_HID in their list of
194  * ACPI/PNP IDs.
195  */
196 static int create_of_modalias(struct acpi_device *acpi_dev, char *modalias,
197                               int size)
198 {
199         struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER };
200         const union acpi_object *of_compatible, *obj;
201         int len, count;
202         int i, nval;
203         char *c;
204
205         acpi_get_name(acpi_dev->handle, ACPI_SINGLE_NAME, &buf);
206         /* DT strings are all in lower case */
207         for (c = buf.pointer; *c != '\0'; c++)
208                 *c = tolower(*c);
209
210         len = snprintf(modalias, size, "of:N%sT", (char *)buf.pointer);
211         ACPI_FREE(buf.pointer);
212
213         if (len <= 0)
214                 return len;
215
216         of_compatible = acpi_dev->data.of_compatible;
217         if (of_compatible->type == ACPI_TYPE_PACKAGE) {
218                 nval = of_compatible->package.count;
219                 obj = of_compatible->package.elements;
220         } else { /* Must be ACPI_TYPE_STRING. */
221                 nval = 1;
222                 obj = of_compatible;
223         }
224         for (i = 0; i < nval; i++, obj++) {
225                 count = snprintf(&modalias[len], size, "C%s",
226                                  obj->string.pointer);
227                 if (count < 0)
228                         return -EINVAL;
229
230                 if (count >= size)
231                         return -ENOMEM;
232
233                 len += count;
234                 size -= count;
235         }
236         modalias[len] = '\0';
237         return len;
238 }
239
240 int __acpi_device_uevent_modalias(struct acpi_device *adev,
241                                   struct kobj_uevent_env *env)
242 {
243         int len;
244
245         if (!adev)
246                 return -ENODEV;
247
248         if (list_empty(&adev->pnp.ids))
249                 return 0;
250
251         if (add_uevent_var(env, "MODALIAS="))
252                 return -ENOMEM;
253
254         len = create_pnp_modalias(adev, &env->buf[env->buflen - 1],
255                                   sizeof(env->buf) - env->buflen);
256         if (len < 0)
257                 return len;
258
259         env->buflen += len;
260         if (!adev->data.of_compatible)
261                 return 0;
262
263         if (len > 0 && add_uevent_var(env, "MODALIAS="))
264                 return -ENOMEM;
265
266         len = create_of_modalias(adev, &env->buf[env->buflen - 1],
267                                  sizeof(env->buf) - env->buflen);
268         if (len < 0)
269                 return len;
270
271         env->buflen += len;
272
273         return 0;
274 }
275
276 /**
277  * acpi_device_uevent_modalias - uevent modalias for ACPI-enumerated devices.
278  *
279  * Create the uevent modalias field for ACPI-enumerated devices.
280  *
281  * Because other buses do not support ACPI HIDs & CIDs, e.g. for a device with
282  * hid:IBM0001 and cid:ACPI0001 you get: "acpi:IBM0001:ACPI0001".
283  */
284 int acpi_device_uevent_modalias(struct device *dev, struct kobj_uevent_env *env)
285 {
286         return __acpi_device_uevent_modalias(acpi_companion_match(dev), env);
287 }
288 EXPORT_SYMBOL_GPL(acpi_device_uevent_modalias);
289
290 static int __acpi_device_modalias(struct acpi_device *adev, char *buf, int size)
291 {
292         int len, count;
293
294         if (!adev)
295                 return -ENODEV;
296
297         if (list_empty(&adev->pnp.ids))
298                 return 0;
299
300         len = create_pnp_modalias(adev, buf, size - 1);
301         if (len < 0) {
302                 return len;
303         } else if (len > 0) {
304                 buf[len++] = '\n';
305                 size -= len;
306         }
307         if (!adev->data.of_compatible)
308                 return len;
309
310         count = create_of_modalias(adev, buf + len, size - 1);
311         if (count < 0) {
312                 return count;
313         } else if (count > 0) {
314                 len += count;
315                 buf[len++] = '\n';
316         }
317
318         return len;
319 }
320
321 /**
322  * acpi_device_modalias - modalias sysfs attribute for ACPI-enumerated devices.
323  *
324  * Create the modalias sysfs attribute for ACPI-enumerated devices.
325  *
326  * Because other buses do not support ACPI HIDs & CIDs, e.g. for a device with
327  * hid:IBM0001 and cid:ACPI0001 you get: "acpi:IBM0001:ACPI0001".
328  */
329 int acpi_device_modalias(struct device *dev, char *buf, int size)
330 {
331         return __acpi_device_modalias(acpi_companion_match(dev), buf, size);
332 }
333 EXPORT_SYMBOL_GPL(acpi_device_modalias);
334
335 static ssize_t
336 acpi_device_modalias_show(struct device *dev, struct device_attribute *attr, char *buf) {
337         return __acpi_device_modalias(to_acpi_device(dev), buf, 1024);
338 }
339 static DEVICE_ATTR(modalias, 0444, acpi_device_modalias_show, NULL);
340
341 static ssize_t real_power_state_show(struct device *dev,
342                                      struct device_attribute *attr, char *buf)
343 {
344         struct acpi_device *adev = to_acpi_device(dev);
345         int state;
346         int ret;
347
348         ret = acpi_device_get_power(adev, &state);
349         if (ret)
350                 return ret;
351
352         return sprintf(buf, "%s\n", acpi_power_state_string(state));
353 }
354
355 static DEVICE_ATTR(real_power_state, 0444, real_power_state_show, NULL);
356
357 static ssize_t power_state_show(struct device *dev,
358                                 struct device_attribute *attr, char *buf)
359 {
360         struct acpi_device *adev = to_acpi_device(dev);
361
362         return sprintf(buf, "%s\n", acpi_power_state_string(adev->power.state));
363 }
364
365 static DEVICE_ATTR(power_state, 0444, power_state_show, NULL);
366
367 static ssize_t
368 acpi_eject_store(struct device *d, struct device_attribute *attr,
369                 const char *buf, size_t count)
370 {
371         struct acpi_device *acpi_device = to_acpi_device(d);
372         acpi_object_type not_used;
373         acpi_status status;
374
375         if (!count || buf[0] != '1')
376                 return -EINVAL;
377
378         if ((!acpi_device->handler || !acpi_device->handler->hotplug.enabled)
379             && !acpi_device->driver)
380                 return -ENODEV;
381
382         status = acpi_get_type(acpi_device->handle, &not_used);
383         if (ACPI_FAILURE(status) || !acpi_device->flags.ejectable)
384                 return -ENODEV;
385
386         get_device(&acpi_device->dev);
387         status = acpi_hotplug_schedule(acpi_device, ACPI_OST_EC_OSPM_EJECT);
388         if (ACPI_SUCCESS(status))
389                 return count;
390
391         put_device(&acpi_device->dev);
392         acpi_evaluate_ost(acpi_device->handle, ACPI_OST_EC_OSPM_EJECT,
393                           ACPI_OST_SC_NON_SPECIFIC_FAILURE, NULL);
394         return status == AE_NO_MEMORY ? -ENOMEM : -EAGAIN;
395 }
396
397 static DEVICE_ATTR(eject, 0200, NULL, acpi_eject_store);
398
399 static ssize_t
400 acpi_device_hid_show(struct device *dev, struct device_attribute *attr, char *buf) {
401         struct acpi_device *acpi_dev = to_acpi_device(dev);
402
403         return sprintf(buf, "%s\n", acpi_device_hid(acpi_dev));
404 }
405 static DEVICE_ATTR(hid, 0444, acpi_device_hid_show, NULL);
406
407 static ssize_t acpi_device_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 }
414 static DEVICE_ATTR(uid, 0444, acpi_device_uid_show, NULL);
415
416 static ssize_t acpi_device_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         return sprintf(buf, "0x%08x\n",
422                        (unsigned int)(acpi_dev->pnp.bus_address));
423 }
424 static DEVICE_ATTR(adr, 0444, acpi_device_adr_show, NULL);
425
426 static ssize_t acpi_device_path_show(struct device *dev,
427                                      struct device_attribute *attr, char *buf)
428 {
429         struct acpi_device *acpi_dev = to_acpi_device(dev);
430
431         return acpi_object_path(acpi_dev->handle, buf);
432 }
433 static DEVICE_ATTR(path, 0444, acpi_device_path_show, NULL);
434
435 /* sysfs file that shows description text from the ACPI _STR method */
436 static ssize_t description_show(struct device *dev,
437                                 struct device_attribute *attr,
438                                 char *buf) {
439         struct acpi_device *acpi_dev = to_acpi_device(dev);
440         int result;
441
442         if (acpi_dev->pnp.str_obj == NULL)
443                 return 0;
444
445         /*
446          * The _STR object contains a Unicode identifier for a device.
447          * We need to convert to utf-8 so it can be displayed.
448          */
449         result = utf16s_to_utf8s(
450                 (wchar_t *)acpi_dev->pnp.str_obj->buffer.pointer,
451                 acpi_dev->pnp.str_obj->buffer.length,
452                 UTF16_LITTLE_ENDIAN, buf,
453                 PAGE_SIZE);
454
455         buf[result++] = '\n';
456
457         return result;
458 }
459 static DEVICE_ATTR(description, 0444, description_show, NULL);
460
461 static ssize_t
462 acpi_device_sun_show(struct device *dev, struct device_attribute *attr,
463                      char *buf) {
464         struct acpi_device *acpi_dev = to_acpi_device(dev);
465         acpi_status status;
466         unsigned long long sun;
467
468         status = acpi_evaluate_integer(acpi_dev->handle, "_SUN", NULL, &sun);
469         if (ACPI_FAILURE(status))
470                 return -ENODEV;
471
472         return sprintf(buf, "%llu\n", sun);
473 }
474 static DEVICE_ATTR(sun, 0444, acpi_device_sun_show, NULL);
475
476 static ssize_t status_show(struct device *dev, struct device_attribute *attr,
477                                 char *buf) {
478         struct acpi_device *acpi_dev = to_acpi_device(dev);
479         acpi_status status;
480         unsigned long long sta;
481
482         status = acpi_evaluate_integer(acpi_dev->handle, "_STA", NULL, &sta);
483         if (ACPI_FAILURE(status))
484                 return -ENODEV;
485
486         return sprintf(buf, "%llu\n", sta);
487 }
488 static DEVICE_ATTR_RO(status);
489
490 /**
491  * acpi_device_setup_files - Create sysfs attributes of an ACPI device.
492  * @dev: ACPI device object.
493  */
494 int acpi_device_setup_files(struct acpi_device *dev)
495 {
496         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
497         acpi_status status;
498         int result = 0;
499
500         /*
501          * Devices gotten from FADT don't have a "path" attribute
502          */
503         if (dev->handle) {
504                 result = device_create_file(&dev->dev, &dev_attr_path);
505                 if (result)
506                         goto end;
507         }
508
509         if (!list_empty(&dev->pnp.ids)) {
510                 result = device_create_file(&dev->dev, &dev_attr_hid);
511                 if (result)
512                         goto end;
513
514                 result = device_create_file(&dev->dev, &dev_attr_modalias);
515                 if (result)
516                         goto end;
517         }
518
519         /*
520          * If device has _STR, 'description' file is created
521          */
522         if (acpi_has_method(dev->handle, "_STR")) {
523                 status = acpi_evaluate_object(dev->handle, "_STR",
524                                         NULL, &buffer);
525                 if (ACPI_FAILURE(status))
526                         buffer.pointer = NULL;
527                 dev->pnp.str_obj = buffer.pointer;
528                 result = device_create_file(&dev->dev, &dev_attr_description);
529                 if (result)
530                         goto end;
531         }
532
533         if (dev->pnp.type.bus_address)
534                 result = device_create_file(&dev->dev, &dev_attr_adr);
535         if (dev->pnp.unique_id)
536                 result = device_create_file(&dev->dev, &dev_attr_uid);
537
538         if (acpi_has_method(dev->handle, "_SUN")) {
539                 result = device_create_file(&dev->dev, &dev_attr_sun);
540                 if (result)
541                         goto end;
542         }
543
544         if (acpi_has_method(dev->handle, "_STA")) {
545                 result = device_create_file(&dev->dev, &dev_attr_status);
546                 if (result)
547                         goto end;
548         }
549
550         /*
551          * If device has _EJ0, 'eject' file is created that is used to trigger
552          * hot-removal function from userland.
553          */
554         if (acpi_has_method(dev->handle, "_EJ0")) {
555                 result = device_create_file(&dev->dev, &dev_attr_eject);
556                 if (result)
557                         return result;
558         }
559
560         if (dev->flags.power_manageable) {
561                 result = device_create_file(&dev->dev, &dev_attr_power_state);
562                 if (result)
563                         return result;
564
565                 if (dev->power.flags.power_resources)
566                         result = device_create_file(&dev->dev,
567                                                     &dev_attr_real_power_state);
568         }
569
570         acpi_expose_nondev_subnodes(&dev->dev.kobj, &dev->data);
571
572 end:
573         return result;
574 }
575
576 /**
577  * acpi_device_remove_files - Remove sysfs attributes of an ACPI device.
578  * @dev: ACPI device object.
579  */
580 void acpi_device_remove_files(struct acpi_device *dev)
581 {
582         acpi_hide_nondev_subnodes(&dev->data);
583
584         if (dev->flags.power_manageable) {
585                 device_remove_file(&dev->dev, &dev_attr_power_state);
586                 if (dev->power.flags.power_resources)
587                         device_remove_file(&dev->dev,
588                                            &dev_attr_real_power_state);
589         }
590
591         /*
592          * If device has _STR, remove 'description' file
593          */
594         if (acpi_has_method(dev->handle, "_STR")) {
595                 kfree(dev->pnp.str_obj);
596                 device_remove_file(&dev->dev, &dev_attr_description);
597         }
598         /*
599          * If device has _EJ0, remove 'eject' file.
600          */
601         if (acpi_has_method(dev->handle, "_EJ0"))
602                 device_remove_file(&dev->dev, &dev_attr_eject);
603
604         if (acpi_has_method(dev->handle, "_SUN"))
605                 device_remove_file(&dev->dev, &dev_attr_sun);
606
607         if (dev->pnp.unique_id)
608                 device_remove_file(&dev->dev, &dev_attr_uid);
609         if (dev->pnp.type.bus_address)
610                 device_remove_file(&dev->dev, &dev_attr_adr);
611         device_remove_file(&dev->dev, &dev_attr_modalias);
612         device_remove_file(&dev->dev, &dev_attr_hid);
613         if (acpi_has_method(dev->handle, "_STA"))
614                 device_remove_file(&dev->dev, &dev_attr_status);
615         if (dev->handle)
616                 device_remove_file(&dev->dev, &dev_attr_path);
617 }