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torvalds
GitHub Repository: torvalds/linux
Path: blob/master/drivers/hid/hid-core.c
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1
// SPDX-License-Identifier: GPL-2.0-or-later
2
/*
3
* HID support for Linux
4
*
5
* Copyright (c) 1999 Andreas Gal
6
* Copyright (c) 2000-2005 Vojtech Pavlik <[email protected]>
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* Copyright (c) 2005 Michael Haboustak <[email protected]> for Concept2, Inc
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* Copyright (c) 2006-2012 Jiri Kosina
9
*/
10
11
/*
12
*/
13
14
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
15
16
#include <linux/module.h>
17
#include <linux/slab.h>
18
#include <linux/init.h>
19
#include <linux/kernel.h>
20
#include <linux/list.h>
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#include <linux/mm.h>
22
#include <linux/spinlock.h>
23
#include <linux/unaligned.h>
24
#include <asm/byteorder.h>
25
#include <linux/input.h>
26
#include <linux/wait.h>
27
#include <linux/vmalloc.h>
28
#include <linux/sched.h>
29
#include <linux/semaphore.h>
30
31
#include <linux/hid.h>
32
#include <linux/hiddev.h>
33
#include <linux/hid-debug.h>
34
#include <linux/hidraw.h>
35
36
#include "hid-ids.h"
37
38
/*
39
* Version Information
40
*/
41
42
#define DRIVER_DESC "HID core driver"
43
44
static int hid_ignore_special_drivers = 0;
45
module_param_named(ignore_special_drivers, hid_ignore_special_drivers, int, 0600);
46
MODULE_PARM_DESC(ignore_special_drivers, "Ignore any special drivers and handle all devices by generic driver");
47
48
/*
49
* Convert a signed n-bit integer to signed 32-bit integer.
50
*/
51
52
static s32 snto32(__u32 value, unsigned int n)
53
{
54
if (!value || !n)
55
return 0;
56
57
if (n > 32)
58
n = 32;
59
60
return sign_extend32(value, n - 1);
61
}
62
63
/*
64
* Convert a signed 32-bit integer to a signed n-bit integer.
65
*/
66
67
static u32 s32ton(__s32 value, unsigned int n)
68
{
69
s32 a;
70
71
if (!value || !n)
72
return 0;
73
74
a = value >> (n - 1);
75
if (a && a != -1)
76
return value < 0 ? 1 << (n - 1) : (1 << (n - 1)) - 1;
77
return value & ((1 << n) - 1);
78
}
79
80
/*
81
* Register a new report for a device.
82
*/
83
84
struct hid_report *hid_register_report(struct hid_device *device,
85
enum hid_report_type type, unsigned int id,
86
unsigned int application)
87
{
88
struct hid_report_enum *report_enum = device->report_enum + type;
89
struct hid_report *report;
90
91
if (id >= HID_MAX_IDS)
92
return NULL;
93
if (report_enum->report_id_hash[id])
94
return report_enum->report_id_hash[id];
95
96
report = kzalloc(sizeof(struct hid_report), GFP_KERNEL);
97
if (!report)
98
return NULL;
99
100
if (id != 0)
101
report_enum->numbered = 1;
102
103
report->id = id;
104
report->type = type;
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report->size = 0;
106
report->device = device;
107
report->application = application;
108
report_enum->report_id_hash[id] = report;
109
110
list_add_tail(&report->list, &report_enum->report_list);
111
INIT_LIST_HEAD(&report->field_entry_list);
112
113
return report;
114
}
115
EXPORT_SYMBOL_GPL(hid_register_report);
116
117
/*
118
* Register a new field for this report.
119
*/
120
121
static struct hid_field *hid_register_field(struct hid_report *report, unsigned usages)
122
{
123
struct hid_field *field;
124
125
if (report->maxfield == HID_MAX_FIELDS) {
126
hid_err(report->device, "too many fields in report\n");
127
return NULL;
128
}
129
130
field = kvzalloc((sizeof(struct hid_field) +
131
usages * sizeof(struct hid_usage) +
132
3 * usages * sizeof(unsigned int)), GFP_KERNEL);
133
if (!field)
134
return NULL;
135
136
field->index = report->maxfield++;
137
report->field[field->index] = field;
138
field->usage = (struct hid_usage *)(field + 1);
139
field->value = (s32 *)(field->usage + usages);
140
field->new_value = (s32 *)(field->value + usages);
141
field->usages_priorities = (s32 *)(field->new_value + usages);
142
field->report = report;
143
144
return field;
145
}
146
147
/*
148
* Open a collection. The type/usage is pushed on the stack.
149
*/
150
151
static int open_collection(struct hid_parser *parser, unsigned type)
152
{
153
struct hid_collection *collection;
154
unsigned usage;
155
int collection_index;
156
157
usage = parser->local.usage[0];
158
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if (parser->collection_stack_ptr == parser->collection_stack_size) {
160
unsigned int *collection_stack;
161
unsigned int new_size = parser->collection_stack_size +
162
HID_COLLECTION_STACK_SIZE;
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collection_stack = krealloc(parser->collection_stack,
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new_size * sizeof(unsigned int),
166
GFP_KERNEL);
167
if (!collection_stack)
168
return -ENOMEM;
169
170
parser->collection_stack = collection_stack;
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parser->collection_stack_size = new_size;
172
}
173
174
if (parser->device->maxcollection == parser->device->collection_size) {
175
collection = kmalloc(
176
array3_size(sizeof(struct hid_collection),
177
parser->device->collection_size,
178
2),
179
GFP_KERNEL);
180
if (collection == NULL) {
181
hid_err(parser->device, "failed to reallocate collection array\n");
182
return -ENOMEM;
183
}
184
memcpy(collection, parser->device->collection,
185
sizeof(struct hid_collection) *
186
parser->device->collection_size);
187
memset(collection + parser->device->collection_size, 0,
188
sizeof(struct hid_collection) *
189
parser->device->collection_size);
190
kfree(parser->device->collection);
191
parser->device->collection = collection;
192
parser->device->collection_size *= 2;
193
}
194
195
parser->collection_stack[parser->collection_stack_ptr++] =
196
parser->device->maxcollection;
197
198
collection_index = parser->device->maxcollection++;
199
collection = parser->device->collection + collection_index;
200
collection->type = type;
201
collection->usage = usage;
202
collection->level = parser->collection_stack_ptr - 1;
203
collection->parent_idx = (collection->level == 0) ? -1 :
204
parser->collection_stack[collection->level - 1];
205
206
if (type == HID_COLLECTION_APPLICATION)
207
parser->device->maxapplication++;
208
209
return 0;
210
}
211
212
/*
213
* Close a collection.
214
*/
215
216
static int close_collection(struct hid_parser *parser)
217
{
218
if (!parser->collection_stack_ptr) {
219
hid_err(parser->device, "collection stack underflow\n");
220
return -EINVAL;
221
}
222
parser->collection_stack_ptr--;
223
return 0;
224
}
225
226
/*
227
* Climb up the stack, search for the specified collection type
228
* and return the usage.
229
*/
230
231
static unsigned hid_lookup_collection(struct hid_parser *parser, unsigned type)
232
{
233
struct hid_collection *collection = parser->device->collection;
234
int n;
235
236
for (n = parser->collection_stack_ptr - 1; n >= 0; n--) {
237
unsigned index = parser->collection_stack[n];
238
if (collection[index].type == type)
239
return collection[index].usage;
240
}
241
return 0; /* we know nothing about this usage type */
242
}
243
244
/*
245
* Concatenate usage which defines 16 bits or less with the
246
* currently defined usage page to form a 32 bit usage
247
*/
248
249
static void complete_usage(struct hid_parser *parser, unsigned int index)
250
{
251
parser->local.usage[index] &= 0xFFFF;
252
parser->local.usage[index] |=
253
(parser->global.usage_page & 0xFFFF) << 16;
254
}
255
256
/*
257
* Add a usage to the temporary parser table.
258
*/
259
260
static int hid_add_usage(struct hid_parser *parser, unsigned usage, u8 size)
261
{
262
if (parser->local.usage_index >= HID_MAX_USAGES) {
263
hid_err(parser->device, "usage index exceeded\n");
264
return -1;
265
}
266
parser->local.usage[parser->local.usage_index] = usage;
267
268
/*
269
* If Usage item only includes usage id, concatenate it with
270
* currently defined usage page
271
*/
272
if (size <= 2)
273
complete_usage(parser, parser->local.usage_index);
274
275
parser->local.usage_size[parser->local.usage_index] = size;
276
parser->local.collection_index[parser->local.usage_index] =
277
parser->collection_stack_ptr ?
278
parser->collection_stack[parser->collection_stack_ptr - 1] : 0;
279
parser->local.usage_index++;
280
return 0;
281
}
282
283
/*
284
* Register a new field for this report.
285
*/
286
287
static int hid_add_field(struct hid_parser *parser, unsigned report_type, unsigned flags)
288
{
289
struct hid_report *report;
290
struct hid_field *field;
291
unsigned int max_buffer_size = HID_MAX_BUFFER_SIZE;
292
unsigned int usages;
293
unsigned int offset;
294
unsigned int i;
295
unsigned int application;
296
297
application = hid_lookup_collection(parser, HID_COLLECTION_APPLICATION);
298
299
report = hid_register_report(parser->device, report_type,
300
parser->global.report_id, application);
301
if (!report) {
302
hid_err(parser->device, "hid_register_report failed\n");
303
return -1;
304
}
305
306
/* Handle both signed and unsigned cases properly */
307
if ((parser->global.logical_minimum < 0 &&
308
parser->global.logical_maximum <
309
parser->global.logical_minimum) ||
310
(parser->global.logical_minimum >= 0 &&
311
(__u32)parser->global.logical_maximum <
312
(__u32)parser->global.logical_minimum)) {
313
dbg_hid("logical range invalid 0x%x 0x%x\n",
314
parser->global.logical_minimum,
315
parser->global.logical_maximum);
316
return -1;
317
}
318
319
offset = report->size;
320
report->size += parser->global.report_size * parser->global.report_count;
321
322
if (parser->device->ll_driver->max_buffer_size)
323
max_buffer_size = parser->device->ll_driver->max_buffer_size;
324
325
/* Total size check: Allow for possible report index byte */
326
if (report->size > (max_buffer_size - 1) << 3) {
327
hid_err(parser->device, "report is too long\n");
328
return -1;
329
}
330
331
if (!parser->local.usage_index) /* Ignore padding fields */
332
return 0;
333
334
usages = max_t(unsigned, parser->local.usage_index,
335
parser->global.report_count);
336
337
field = hid_register_field(report, usages);
338
if (!field)
339
return 0;
340
341
field->physical = hid_lookup_collection(parser, HID_COLLECTION_PHYSICAL);
342
field->logical = hid_lookup_collection(parser, HID_COLLECTION_LOGICAL);
343
field->application = application;
344
345
for (i = 0; i < usages; i++) {
346
unsigned j = i;
347
/* Duplicate the last usage we parsed if we have excess values */
348
if (i >= parser->local.usage_index)
349
j = parser->local.usage_index - 1;
350
field->usage[i].hid = parser->local.usage[j];
351
field->usage[i].collection_index =
352
parser->local.collection_index[j];
353
field->usage[i].usage_index = i;
354
field->usage[i].resolution_multiplier = 1;
355
}
356
357
field->maxusage = usages;
358
field->flags = flags;
359
field->report_offset = offset;
360
field->report_type = report_type;
361
field->report_size = parser->global.report_size;
362
field->report_count = parser->global.report_count;
363
field->logical_minimum = parser->global.logical_minimum;
364
field->logical_maximum = parser->global.logical_maximum;
365
field->physical_minimum = parser->global.physical_minimum;
366
field->physical_maximum = parser->global.physical_maximum;
367
field->unit_exponent = parser->global.unit_exponent;
368
field->unit = parser->global.unit;
369
370
return 0;
371
}
372
373
/*
374
* Read data value from item.
375
*/
376
377
static u32 item_udata(struct hid_item *item)
378
{
379
switch (item->size) {
380
case 1: return item->data.u8;
381
case 2: return item->data.u16;
382
case 4: return item->data.u32;
383
}
384
return 0;
385
}
386
387
static s32 item_sdata(struct hid_item *item)
388
{
389
switch (item->size) {
390
case 1: return item->data.s8;
391
case 2: return item->data.s16;
392
case 4: return item->data.s32;
393
}
394
return 0;
395
}
396
397
/*
398
* Process a global item.
399
*/
400
401
static int hid_parser_global(struct hid_parser *parser, struct hid_item *item)
402
{
403
__s32 raw_value;
404
switch (item->tag) {
405
case HID_GLOBAL_ITEM_TAG_PUSH:
406
407
if (parser->global_stack_ptr == HID_GLOBAL_STACK_SIZE) {
408
hid_err(parser->device, "global environment stack overflow\n");
409
return -1;
410
}
411
412
memcpy(parser->global_stack + parser->global_stack_ptr++,
413
&parser->global, sizeof(struct hid_global));
414
return 0;
415
416
case HID_GLOBAL_ITEM_TAG_POP:
417
418
if (!parser->global_stack_ptr) {
419
hid_err(parser->device, "global environment stack underflow\n");
420
return -1;
421
}
422
423
memcpy(&parser->global, parser->global_stack +
424
--parser->global_stack_ptr, sizeof(struct hid_global));
425
return 0;
426
427
case HID_GLOBAL_ITEM_TAG_USAGE_PAGE:
428
parser->global.usage_page = item_udata(item);
429
return 0;
430
431
case HID_GLOBAL_ITEM_TAG_LOGICAL_MINIMUM:
432
parser->global.logical_minimum = item_sdata(item);
433
return 0;
434
435
case HID_GLOBAL_ITEM_TAG_LOGICAL_MAXIMUM:
436
if (parser->global.logical_minimum < 0)
437
parser->global.logical_maximum = item_sdata(item);
438
else
439
parser->global.logical_maximum = item_udata(item);
440
return 0;
441
442
case HID_GLOBAL_ITEM_TAG_PHYSICAL_MINIMUM:
443
parser->global.physical_minimum = item_sdata(item);
444
return 0;
445
446
case HID_GLOBAL_ITEM_TAG_PHYSICAL_MAXIMUM:
447
if (parser->global.physical_minimum < 0)
448
parser->global.physical_maximum = item_sdata(item);
449
else
450
parser->global.physical_maximum = item_udata(item);
451
return 0;
452
453
case HID_GLOBAL_ITEM_TAG_UNIT_EXPONENT:
454
/* Many devices provide unit exponent as a two's complement
455
* nibble due to the common misunderstanding of HID
456
* specification 1.11, 6.2.2.7 Global Items. Attempt to handle
457
* both this and the standard encoding. */
458
raw_value = item_sdata(item);
459
if (!(raw_value & 0xfffffff0))
460
parser->global.unit_exponent = snto32(raw_value, 4);
461
else
462
parser->global.unit_exponent = raw_value;
463
return 0;
464
465
case HID_GLOBAL_ITEM_TAG_UNIT:
466
parser->global.unit = item_udata(item);
467
return 0;
468
469
case HID_GLOBAL_ITEM_TAG_REPORT_SIZE:
470
parser->global.report_size = item_udata(item);
471
if (parser->global.report_size > 256) {
472
hid_err(parser->device, "invalid report_size %d\n",
473
parser->global.report_size);
474
return -1;
475
}
476
return 0;
477
478
case HID_GLOBAL_ITEM_TAG_REPORT_COUNT:
479
parser->global.report_count = item_udata(item);
480
if (parser->global.report_count > HID_MAX_USAGES) {
481
hid_err(parser->device, "invalid report_count %d\n",
482
parser->global.report_count);
483
return -1;
484
}
485
return 0;
486
487
case HID_GLOBAL_ITEM_TAG_REPORT_ID:
488
parser->global.report_id = item_udata(item);
489
if (parser->global.report_id == 0 ||
490
parser->global.report_id >= HID_MAX_IDS) {
491
hid_err(parser->device, "report_id %u is invalid\n",
492
parser->global.report_id);
493
return -1;
494
}
495
return 0;
496
497
default:
498
hid_err(parser->device, "unknown global tag 0x%x\n", item->tag);
499
return -1;
500
}
501
}
502
503
/*
504
* Process a local item.
505
*/
506
507
static int hid_parser_local(struct hid_parser *parser, struct hid_item *item)
508
{
509
__u32 data;
510
unsigned n;
511
__u32 count;
512
513
data = item_udata(item);
514
515
switch (item->tag) {
516
case HID_LOCAL_ITEM_TAG_DELIMITER:
517
518
if (data) {
519
/*
520
* We treat items before the first delimiter
521
* as global to all usage sets (branch 0).
522
* In the moment we process only these global
523
* items and the first delimiter set.
524
*/
525
if (parser->local.delimiter_depth != 0) {
526
hid_err(parser->device, "nested delimiters\n");
527
return -1;
528
}
529
parser->local.delimiter_depth++;
530
parser->local.delimiter_branch++;
531
} else {
532
if (parser->local.delimiter_depth < 1) {
533
hid_err(parser->device, "bogus close delimiter\n");
534
return -1;
535
}
536
parser->local.delimiter_depth--;
537
}
538
return 0;
539
540
case HID_LOCAL_ITEM_TAG_USAGE:
541
542
if (parser->local.delimiter_branch > 1) {
543
dbg_hid("alternative usage ignored\n");
544
return 0;
545
}
546
547
return hid_add_usage(parser, data, item->size);
548
549
case HID_LOCAL_ITEM_TAG_USAGE_MINIMUM:
550
551
if (parser->local.delimiter_branch > 1) {
552
dbg_hid("alternative usage ignored\n");
553
return 0;
554
}
555
556
parser->local.usage_minimum = data;
557
return 0;
558
559
case HID_LOCAL_ITEM_TAG_USAGE_MAXIMUM:
560
561
if (parser->local.delimiter_branch > 1) {
562
dbg_hid("alternative usage ignored\n");
563
return 0;
564
}
565
566
count = data - parser->local.usage_minimum;
567
if (count + parser->local.usage_index >= HID_MAX_USAGES) {
568
/*
569
* We do not warn if the name is not set, we are
570
* actually pre-scanning the device.
571
*/
572
if (dev_name(&parser->device->dev))
573
hid_warn(parser->device,
574
"ignoring exceeding usage max\n");
575
data = HID_MAX_USAGES - parser->local.usage_index +
576
parser->local.usage_minimum - 1;
577
if (data <= 0) {
578
hid_err(parser->device,
579
"no more usage index available\n");
580
return -1;
581
}
582
}
583
584
for (n = parser->local.usage_minimum; n <= data; n++)
585
if (hid_add_usage(parser, n, item->size)) {
586
dbg_hid("hid_add_usage failed\n");
587
return -1;
588
}
589
return 0;
590
591
default:
592
593
dbg_hid("unknown local item tag 0x%x\n", item->tag);
594
return 0;
595
}
596
return 0;
597
}
598
599
/*
600
* Concatenate Usage Pages into Usages where relevant:
601
* As per specification, 6.2.2.8: "When the parser encounters a main item it
602
* concatenates the last declared Usage Page with a Usage to form a complete
603
* usage value."
604
*/
605
606
static void hid_concatenate_last_usage_page(struct hid_parser *parser)
607
{
608
int i;
609
unsigned int usage_page;
610
unsigned int current_page;
611
612
if (!parser->local.usage_index)
613
return;
614
615
usage_page = parser->global.usage_page;
616
617
/*
618
* Concatenate usage page again only if last declared Usage Page
619
* has not been already used in previous usages concatenation
620
*/
621
for (i = parser->local.usage_index - 1; i >= 0; i--) {
622
if (parser->local.usage_size[i] > 2)
623
/* Ignore extended usages */
624
continue;
625
626
current_page = parser->local.usage[i] >> 16;
627
if (current_page == usage_page)
628
break;
629
630
complete_usage(parser, i);
631
}
632
}
633
634
/*
635
* Process a main item.
636
*/
637
638
static int hid_parser_main(struct hid_parser *parser, struct hid_item *item)
639
{
640
__u32 data;
641
int ret;
642
643
hid_concatenate_last_usage_page(parser);
644
645
data = item_udata(item);
646
647
switch (item->tag) {
648
case HID_MAIN_ITEM_TAG_BEGIN_COLLECTION:
649
ret = open_collection(parser, data & 0xff);
650
break;
651
case HID_MAIN_ITEM_TAG_END_COLLECTION:
652
ret = close_collection(parser);
653
break;
654
case HID_MAIN_ITEM_TAG_INPUT:
655
ret = hid_add_field(parser, HID_INPUT_REPORT, data);
656
break;
657
case HID_MAIN_ITEM_TAG_OUTPUT:
658
ret = hid_add_field(parser, HID_OUTPUT_REPORT, data);
659
break;
660
case HID_MAIN_ITEM_TAG_FEATURE:
661
ret = hid_add_field(parser, HID_FEATURE_REPORT, data);
662
break;
663
default:
664
if (item->tag >= HID_MAIN_ITEM_TAG_RESERVED_MIN &&
665
item->tag <= HID_MAIN_ITEM_TAG_RESERVED_MAX)
666
hid_warn_ratelimited(parser->device, "reserved main item tag 0x%x\n", item->tag);
667
else
668
hid_warn_ratelimited(parser->device, "unknown main item tag 0x%x\n", item->tag);
669
ret = 0;
670
}
671
672
memset(&parser->local, 0, sizeof(parser->local)); /* Reset the local parser environment */
673
674
return ret;
675
}
676
677
/*
678
* Process a reserved item.
679
*/
680
681
static int hid_parser_reserved(struct hid_parser *parser, struct hid_item *item)
682
{
683
dbg_hid("reserved item type, tag 0x%x\n", item->tag);
684
return 0;
685
}
686
687
/*
688
* Free a report and all registered fields. The field->usage and
689
* field->value table's are allocated behind the field, so we need
690
* only to free(field) itself.
691
*/
692
693
static void hid_free_report(struct hid_report *report)
694
{
695
unsigned n;
696
697
kfree(report->field_entries);
698
699
for (n = 0; n < report->maxfield; n++)
700
kvfree(report->field[n]);
701
kfree(report);
702
}
703
704
/*
705
* Close report. This function returns the device
706
* state to the point prior to hid_open_report().
707
*/
708
static void hid_close_report(struct hid_device *device)
709
{
710
unsigned i, j;
711
712
for (i = 0; i < HID_REPORT_TYPES; i++) {
713
struct hid_report_enum *report_enum = device->report_enum + i;
714
715
for (j = 0; j < HID_MAX_IDS; j++) {
716
struct hid_report *report = report_enum->report_id_hash[j];
717
if (report)
718
hid_free_report(report);
719
}
720
memset(report_enum, 0, sizeof(*report_enum));
721
INIT_LIST_HEAD(&report_enum->report_list);
722
}
723
724
/*
725
* If the HID driver had a rdesc_fixup() callback, dev->rdesc
726
* will be allocated by hid-core and needs to be freed.
727
* Otherwise, it is either equal to dev_rdesc or bpf_rdesc, in
728
* which cases it'll be freed later on device removal or destroy.
729
*/
730
if (device->rdesc != device->dev_rdesc && device->rdesc != device->bpf_rdesc)
731
kfree(device->rdesc);
732
device->rdesc = NULL;
733
device->rsize = 0;
734
735
kfree(device->collection);
736
device->collection = NULL;
737
device->collection_size = 0;
738
device->maxcollection = 0;
739
device->maxapplication = 0;
740
741
device->status &= ~HID_STAT_PARSED;
742
}
743
744
static inline void hid_free_bpf_rdesc(struct hid_device *hdev)
745
{
746
/* bpf_rdesc is either equal to dev_rdesc or allocated by call_hid_bpf_rdesc_fixup() */
747
if (hdev->bpf_rdesc != hdev->dev_rdesc)
748
kfree(hdev->bpf_rdesc);
749
hdev->bpf_rdesc = NULL;
750
}
751
752
/*
753
* Free a device structure, all reports, and all fields.
754
*/
755
756
void hiddev_free(struct kref *ref)
757
{
758
struct hid_device *hid = container_of(ref, struct hid_device, ref);
759
760
hid_close_report(hid);
761
hid_free_bpf_rdesc(hid);
762
kfree(hid->dev_rdesc);
763
kfree(hid);
764
}
765
766
static void hid_device_release(struct device *dev)
767
{
768
struct hid_device *hid = to_hid_device(dev);
769
770
kref_put(&hid->ref, hiddev_free);
771
}
772
773
/*
774
* Fetch a report description item from the data stream. We support long
775
* items, though they are not used yet.
776
*/
777
778
static const u8 *fetch_item(const __u8 *start, const __u8 *end, struct hid_item *item)
779
{
780
u8 b;
781
782
if ((end - start) <= 0)
783
return NULL;
784
785
b = *start++;
786
787
item->type = (b >> 2) & 3;
788
item->tag = (b >> 4) & 15;
789
790
if (item->tag == HID_ITEM_TAG_LONG) {
791
792
item->format = HID_ITEM_FORMAT_LONG;
793
794
if ((end - start) < 2)
795
return NULL;
796
797
item->size = *start++;
798
item->tag = *start++;
799
800
if ((end - start) < item->size)
801
return NULL;
802
803
item->data.longdata = start;
804
start += item->size;
805
return start;
806
}
807
808
item->format = HID_ITEM_FORMAT_SHORT;
809
item->size = BIT(b & 3) >> 1; /* 0, 1, 2, 3 -> 0, 1, 2, 4 */
810
811
if (end - start < item->size)
812
return NULL;
813
814
switch (item->size) {
815
case 0:
816
break;
817
818
case 1:
819
item->data.u8 = *start;
820
break;
821
822
case 2:
823
item->data.u16 = get_unaligned_le16(start);
824
break;
825
826
case 4:
827
item->data.u32 = get_unaligned_le32(start);
828
break;
829
}
830
831
return start + item->size;
832
}
833
834
static void hid_scan_input_usage(struct hid_parser *parser, u32 usage)
835
{
836
struct hid_device *hid = parser->device;
837
838
if (usage == HID_DG_CONTACTID)
839
hid->group = HID_GROUP_MULTITOUCH;
840
}
841
842
static void hid_scan_feature_usage(struct hid_parser *parser, u32 usage)
843
{
844
if (usage == 0xff0000c5 && parser->global.report_count == 256 &&
845
parser->global.report_size == 8)
846
parser->scan_flags |= HID_SCAN_FLAG_MT_WIN_8;
847
848
if (usage == 0xff0000c6 && parser->global.report_count == 1 &&
849
parser->global.report_size == 8)
850
parser->scan_flags |= HID_SCAN_FLAG_MT_WIN_8;
851
}
852
853
static void hid_scan_collection(struct hid_parser *parser, unsigned type)
854
{
855
struct hid_device *hid = parser->device;
856
int i;
857
858
if (((parser->global.usage_page << 16) == HID_UP_SENSOR) &&
859
(type == HID_COLLECTION_PHYSICAL ||
860
type == HID_COLLECTION_APPLICATION))
861
hid->group = HID_GROUP_SENSOR_HUB;
862
863
if (hid->vendor == USB_VENDOR_ID_MICROSOFT &&
864
hid->product == USB_DEVICE_ID_MS_POWER_COVER &&
865
hid->group == HID_GROUP_MULTITOUCH)
866
hid->group = HID_GROUP_GENERIC;
867
868
if ((parser->global.usage_page << 16) == HID_UP_GENDESK)
869
for (i = 0; i < parser->local.usage_index; i++)
870
if (parser->local.usage[i] == HID_GD_POINTER)
871
parser->scan_flags |= HID_SCAN_FLAG_GD_POINTER;
872
873
if ((parser->global.usage_page << 16) >= HID_UP_MSVENDOR)
874
parser->scan_flags |= HID_SCAN_FLAG_VENDOR_SPECIFIC;
875
876
if ((parser->global.usage_page << 16) == HID_UP_GOOGLEVENDOR)
877
for (i = 0; i < parser->local.usage_index; i++)
878
if (parser->local.usage[i] ==
879
(HID_UP_GOOGLEVENDOR | 0x0001))
880
parser->device->group =
881
HID_GROUP_VIVALDI;
882
}
883
884
static int hid_scan_main(struct hid_parser *parser, struct hid_item *item)
885
{
886
__u32 data;
887
int i;
888
889
hid_concatenate_last_usage_page(parser);
890
891
data = item_udata(item);
892
893
switch (item->tag) {
894
case HID_MAIN_ITEM_TAG_BEGIN_COLLECTION:
895
hid_scan_collection(parser, data & 0xff);
896
break;
897
case HID_MAIN_ITEM_TAG_END_COLLECTION:
898
break;
899
case HID_MAIN_ITEM_TAG_INPUT:
900
/* ignore constant inputs, they will be ignored by hid-input */
901
if (data & HID_MAIN_ITEM_CONSTANT)
902
break;
903
for (i = 0; i < parser->local.usage_index; i++)
904
hid_scan_input_usage(parser, parser->local.usage[i]);
905
break;
906
case HID_MAIN_ITEM_TAG_OUTPUT:
907
break;
908
case HID_MAIN_ITEM_TAG_FEATURE:
909
for (i = 0; i < parser->local.usage_index; i++)
910
hid_scan_feature_usage(parser, parser->local.usage[i]);
911
break;
912
}
913
914
/* Reset the local parser environment */
915
memset(&parser->local, 0, sizeof(parser->local));
916
917
return 0;
918
}
919
920
/*
921
* Scan a report descriptor before the device is added to the bus.
922
* Sets device groups and other properties that determine what driver
923
* to load.
924
*/
925
static int hid_scan_report(struct hid_device *hid)
926
{
927
struct hid_parser *parser;
928
struct hid_item item;
929
const __u8 *start = hid->dev_rdesc;
930
const __u8 *end = start + hid->dev_rsize;
931
static int (*dispatch_type[])(struct hid_parser *parser,
932
struct hid_item *item) = {
933
hid_scan_main,
934
hid_parser_global,
935
hid_parser_local,
936
hid_parser_reserved
937
};
938
939
parser = vzalloc(sizeof(struct hid_parser));
940
if (!parser)
941
return -ENOMEM;
942
943
parser->device = hid;
944
hid->group = HID_GROUP_GENERIC;
945
946
/*
947
* In case we are re-scanning after a BPF has been loaded,
948
* we need to use the bpf report descriptor, not the original one.
949
*/
950
if (hid->bpf_rdesc && hid->bpf_rsize) {
951
start = hid->bpf_rdesc;
952
end = start + hid->bpf_rsize;
953
}
954
955
/*
956
* The parsing is simpler than the one in hid_open_report() as we should
957
* be robust against hid errors. Those errors will be raised by
958
* hid_open_report() anyway.
959
*/
960
while ((start = fetch_item(start, end, &item)) != NULL)
961
dispatch_type[item.type](parser, &item);
962
963
/*
964
* Handle special flags set during scanning.
965
*/
966
if ((parser->scan_flags & HID_SCAN_FLAG_MT_WIN_8) &&
967
(hid->group == HID_GROUP_MULTITOUCH))
968
hid->group = HID_GROUP_MULTITOUCH_WIN_8;
969
970
/*
971
* Vendor specific handlings
972
*/
973
switch (hid->vendor) {
974
case USB_VENDOR_ID_WACOM:
975
hid->group = HID_GROUP_WACOM;
976
break;
977
case USB_VENDOR_ID_SYNAPTICS:
978
if (hid->group == HID_GROUP_GENERIC)
979
if ((parser->scan_flags & HID_SCAN_FLAG_VENDOR_SPECIFIC)
980
&& (parser->scan_flags & HID_SCAN_FLAG_GD_POINTER))
981
/*
982
* hid-rmi should take care of them,
983
* not hid-generic
984
*/
985
hid->group = HID_GROUP_RMI;
986
break;
987
}
988
989
kfree(parser->collection_stack);
990
vfree(parser);
991
return 0;
992
}
993
994
/**
995
* hid_parse_report - parse device report
996
*
997
* @hid: hid device
998
* @start: report start
999
* @size: report size
1000
*
1001
* Allocate the device report as read by the bus driver. This function should
1002
* only be called from parse() in ll drivers.
1003
*/
1004
int hid_parse_report(struct hid_device *hid, const __u8 *start, unsigned size)
1005
{
1006
hid->dev_rdesc = kmemdup(start, size, GFP_KERNEL);
1007
if (!hid->dev_rdesc)
1008
return -ENOMEM;
1009
hid->dev_rsize = size;
1010
return 0;
1011
}
1012
EXPORT_SYMBOL_GPL(hid_parse_report);
1013
1014
static const char * const hid_report_names[] = {
1015
"HID_INPUT_REPORT",
1016
"HID_OUTPUT_REPORT",
1017
"HID_FEATURE_REPORT",
1018
};
1019
/**
1020
* hid_validate_values - validate existing device report's value indexes
1021
*
1022
* @hid: hid device
1023
* @type: which report type to examine
1024
* @id: which report ID to examine (0 for first)
1025
* @field_index: which report field to examine
1026
* @report_counts: expected number of values
1027
*
1028
* Validate the number of values in a given field of a given report, after
1029
* parsing.
1030
*/
1031
struct hid_report *hid_validate_values(struct hid_device *hid,
1032
enum hid_report_type type, unsigned int id,
1033
unsigned int field_index,
1034
unsigned int report_counts)
1035
{
1036
struct hid_report *report;
1037
1038
if (type > HID_FEATURE_REPORT) {
1039
hid_err(hid, "invalid HID report type %u\n", type);
1040
return NULL;
1041
}
1042
1043
if (id >= HID_MAX_IDS) {
1044
hid_err(hid, "invalid HID report id %u\n", id);
1045
return NULL;
1046
}
1047
1048
/*
1049
* Explicitly not using hid_get_report() here since it depends on
1050
* ->numbered being checked, which may not always be the case when
1051
* drivers go to access report values.
1052
*/
1053
if (id == 0) {
1054
/*
1055
* Validating on id 0 means we should examine the first
1056
* report in the list.
1057
*/
1058
report = list_first_entry_or_null(
1059
&hid->report_enum[type].report_list,
1060
struct hid_report, list);
1061
} else {
1062
report = hid->report_enum[type].report_id_hash[id];
1063
}
1064
if (!report) {
1065
hid_err(hid, "missing %s %u\n", hid_report_names[type], id);
1066
return NULL;
1067
}
1068
if (report->maxfield <= field_index) {
1069
hid_err(hid, "not enough fields in %s %u\n",
1070
hid_report_names[type], id);
1071
return NULL;
1072
}
1073
if (report->field[field_index]->report_count < report_counts) {
1074
hid_err(hid, "not enough values in %s %u field %u\n",
1075
hid_report_names[type], id, field_index);
1076
return NULL;
1077
}
1078
return report;
1079
}
1080
EXPORT_SYMBOL_GPL(hid_validate_values);
1081
1082
static int hid_calculate_multiplier(struct hid_device *hid,
1083
struct hid_field *multiplier)
1084
{
1085
int m;
1086
__s32 v = *multiplier->value;
1087
__s32 lmin = multiplier->logical_minimum;
1088
__s32 lmax = multiplier->logical_maximum;
1089
__s32 pmin = multiplier->physical_minimum;
1090
__s32 pmax = multiplier->physical_maximum;
1091
1092
/*
1093
* "Because OS implementations will generally divide the control's
1094
* reported count by the Effective Resolution Multiplier, designers
1095
* should take care not to establish a potential Effective
1096
* Resolution Multiplier of zero."
1097
* HID Usage Table, v1.12, Section 4.3.1, p31
1098
*/
1099
if (lmax - lmin == 0)
1100
return 1;
1101
/*
1102
* Handling the unit exponent is left as an exercise to whoever
1103
* finds a device where that exponent is not 0.
1104
*/
1105
m = ((v - lmin)/(lmax - lmin) * (pmax - pmin) + pmin);
1106
if (unlikely(multiplier->unit_exponent != 0)) {
1107
hid_warn(hid,
1108
"unsupported Resolution Multiplier unit exponent %d\n",
1109
multiplier->unit_exponent);
1110
}
1111
1112
/* There are no devices with an effective multiplier > 255 */
1113
if (unlikely(m == 0 || m > 255 || m < -255)) {
1114
hid_warn(hid, "unsupported Resolution Multiplier %d\n", m);
1115
m = 1;
1116
}
1117
1118
return m;
1119
}
1120
1121
static void hid_apply_multiplier_to_field(struct hid_device *hid,
1122
struct hid_field *field,
1123
struct hid_collection *multiplier_collection,
1124
int effective_multiplier)
1125
{
1126
struct hid_collection *collection;
1127
struct hid_usage *usage;
1128
int i;
1129
1130
/*
1131
* If multiplier_collection is NULL, the multiplier applies
1132
* to all fields in the report.
1133
* Otherwise, it is the Logical Collection the multiplier applies to
1134
* but our field may be in a subcollection of that collection.
1135
*/
1136
for (i = 0; i < field->maxusage; i++) {
1137
usage = &field->usage[i];
1138
1139
collection = &hid->collection[usage->collection_index];
1140
while (collection->parent_idx != -1 &&
1141
collection != multiplier_collection)
1142
collection = &hid->collection[collection->parent_idx];
1143
1144
if (collection->parent_idx != -1 ||
1145
multiplier_collection == NULL)
1146
usage->resolution_multiplier = effective_multiplier;
1147
1148
}
1149
}
1150
1151
static void hid_apply_multiplier(struct hid_device *hid,
1152
struct hid_field *multiplier)
1153
{
1154
struct hid_report_enum *rep_enum;
1155
struct hid_report *rep;
1156
struct hid_field *field;
1157
struct hid_collection *multiplier_collection;
1158
int effective_multiplier;
1159
int i;
1160
1161
/*
1162
* "The Resolution Multiplier control must be contained in the same
1163
* Logical Collection as the control(s) to which it is to be applied.
1164
* If no Resolution Multiplier is defined, then the Resolution
1165
* Multiplier defaults to 1. If more than one control exists in a
1166
* Logical Collection, the Resolution Multiplier is associated with
1167
* all controls in the collection. If no Logical Collection is
1168
* defined, the Resolution Multiplier is associated with all
1169
* controls in the report."
1170
* HID Usage Table, v1.12, Section 4.3.1, p30
1171
*
1172
* Thus, search from the current collection upwards until we find a
1173
* logical collection. Then search all fields for that same parent
1174
* collection. Those are the fields the multiplier applies to.
1175
*
1176
* If we have more than one multiplier, it will overwrite the
1177
* applicable fields later.
1178
*/
1179
multiplier_collection = &hid->collection[multiplier->usage->collection_index];
1180
while (multiplier_collection->parent_idx != -1 &&
1181
multiplier_collection->type != HID_COLLECTION_LOGICAL)
1182
multiplier_collection = &hid->collection[multiplier_collection->parent_idx];
1183
if (multiplier_collection->type != HID_COLLECTION_LOGICAL)
1184
multiplier_collection = NULL;
1185
1186
effective_multiplier = hid_calculate_multiplier(hid, multiplier);
1187
1188
rep_enum = &hid->report_enum[HID_INPUT_REPORT];
1189
list_for_each_entry(rep, &rep_enum->report_list, list) {
1190
for (i = 0; i < rep->maxfield; i++) {
1191
field = rep->field[i];
1192
hid_apply_multiplier_to_field(hid, field,
1193
multiplier_collection,
1194
effective_multiplier);
1195
}
1196
}
1197
}
1198
1199
/*
1200
* hid_setup_resolution_multiplier - set up all resolution multipliers
1201
*
1202
* @device: hid device
1203
*
1204
* Search for all Resolution Multiplier Feature Reports and apply their
1205
* value to all matching Input items. This only updates the internal struct
1206
* fields.
1207
*
1208
* The Resolution Multiplier is applied by the hardware. If the multiplier
1209
* is anything other than 1, the hardware will send pre-multiplied events
1210
* so that the same physical interaction generates an accumulated
1211
* accumulated_value = value * * multiplier
1212
* This may be achieved by sending
1213
* - "value * multiplier" for each event, or
1214
* - "value" but "multiplier" times as frequently, or
1215
* - a combination of the above
1216
* The only guarantee is that the same physical interaction always generates
1217
* an accumulated 'value * multiplier'.
1218
*
1219
* This function must be called before any event processing and after
1220
* any SetRequest to the Resolution Multiplier.
1221
*/
1222
void hid_setup_resolution_multiplier(struct hid_device *hid)
1223
{
1224
struct hid_report_enum *rep_enum;
1225
struct hid_report *rep;
1226
struct hid_usage *usage;
1227
int i, j;
1228
1229
rep_enum = &hid->report_enum[HID_FEATURE_REPORT];
1230
list_for_each_entry(rep, &rep_enum->report_list, list) {
1231
for (i = 0; i < rep->maxfield; i++) {
1232
/* Ignore if report count is out of bounds. */
1233
if (rep->field[i]->report_count < 1)
1234
continue;
1235
1236
for (j = 0; j < rep->field[i]->maxusage; j++) {
1237
usage = &rep->field[i]->usage[j];
1238
if (usage->hid == HID_GD_RESOLUTION_MULTIPLIER)
1239
hid_apply_multiplier(hid,
1240
rep->field[i]);
1241
}
1242
}
1243
}
1244
}
1245
EXPORT_SYMBOL_GPL(hid_setup_resolution_multiplier);
1246
1247
/**
1248
* hid_open_report - open a driver-specific device report
1249
*
1250
* @device: hid device
1251
*
1252
* Parse a report description into a hid_device structure. Reports are
1253
* enumerated, fields are attached to these reports.
1254
* 0 returned on success, otherwise nonzero error value.
1255
*
1256
* This function (or the equivalent hid_parse() macro) should only be
1257
* called from probe() in drivers, before starting the device.
1258
*/
1259
int hid_open_report(struct hid_device *device)
1260
{
1261
struct hid_parser *parser;
1262
struct hid_item item;
1263
unsigned int size;
1264
const __u8 *start;
1265
const __u8 *end;
1266
const __u8 *next;
1267
int ret;
1268
int i;
1269
static int (*dispatch_type[])(struct hid_parser *parser,
1270
struct hid_item *item) = {
1271
hid_parser_main,
1272
hid_parser_global,
1273
hid_parser_local,
1274
hid_parser_reserved
1275
};
1276
1277
if (WARN_ON(device->status & HID_STAT_PARSED))
1278
return -EBUSY;
1279
1280
start = device->bpf_rdesc;
1281
if (WARN_ON(!start))
1282
return -ENODEV;
1283
size = device->bpf_rsize;
1284
1285
if (device->driver->report_fixup) {
1286
/*
1287
* device->driver->report_fixup() needs to work
1288
* on a copy of our report descriptor so it can
1289
* change it.
1290
*/
1291
__u8 *buf = kmemdup(start, size, GFP_KERNEL);
1292
1293
if (buf == NULL)
1294
return -ENOMEM;
1295
1296
start = device->driver->report_fixup(device, buf, &size);
1297
1298
/*
1299
* The second kmemdup is required in case report_fixup() returns
1300
* a static read-only memory, but we have no idea if that memory
1301
* needs to be cleaned up or not at the end.
1302
*/
1303
start = kmemdup(start, size, GFP_KERNEL);
1304
kfree(buf);
1305
if (start == NULL)
1306
return -ENOMEM;
1307
}
1308
1309
device->rdesc = start;
1310
device->rsize = size;
1311
1312
parser = vzalloc(sizeof(struct hid_parser));
1313
if (!parser) {
1314
ret = -ENOMEM;
1315
goto alloc_err;
1316
}
1317
1318
parser->device = device;
1319
1320
end = start + size;
1321
1322
device->collection = kcalloc(HID_DEFAULT_NUM_COLLECTIONS,
1323
sizeof(struct hid_collection), GFP_KERNEL);
1324
if (!device->collection) {
1325
ret = -ENOMEM;
1326
goto err;
1327
}
1328
device->collection_size = HID_DEFAULT_NUM_COLLECTIONS;
1329
for (i = 0; i < HID_DEFAULT_NUM_COLLECTIONS; i++)
1330
device->collection[i].parent_idx = -1;
1331
1332
ret = -EINVAL;
1333
while ((next = fetch_item(start, end, &item)) != NULL) {
1334
start = next;
1335
1336
if (item.format != HID_ITEM_FORMAT_SHORT) {
1337
hid_err(device, "unexpected long global item\n");
1338
goto err;
1339
}
1340
1341
if (dispatch_type[item.type](parser, &item)) {
1342
hid_err(device, "item %u %u %u %u parsing failed\n",
1343
item.format, (unsigned)item.size,
1344
(unsigned)item.type, (unsigned)item.tag);
1345
goto err;
1346
}
1347
1348
if (start == end) {
1349
if (parser->collection_stack_ptr) {
1350
hid_err(device, "unbalanced collection at end of report description\n");
1351
goto err;
1352
}
1353
if (parser->local.delimiter_depth) {
1354
hid_err(device, "unbalanced delimiter at end of report description\n");
1355
goto err;
1356
}
1357
1358
/*
1359
* fetch initial values in case the device's
1360
* default multiplier isn't the recommended 1
1361
*/
1362
hid_setup_resolution_multiplier(device);
1363
1364
kfree(parser->collection_stack);
1365
vfree(parser);
1366
device->status |= HID_STAT_PARSED;
1367
1368
return 0;
1369
}
1370
}
1371
1372
hid_err(device, "item fetching failed at offset %u/%u\n",
1373
size - (unsigned int)(end - start), size);
1374
err:
1375
kfree(parser->collection_stack);
1376
alloc_err:
1377
vfree(parser);
1378
hid_close_report(device);
1379
return ret;
1380
}
1381
EXPORT_SYMBOL_GPL(hid_open_report);
1382
1383
/*
1384
* Extract/implement a data field from/to a little endian report (bit array).
1385
*
1386
* Code sort-of follows HID spec:
1387
* http://www.usb.org/developers/hidpage/HID1_11.pdf
1388
*
1389
* While the USB HID spec allows unlimited length bit fields in "report
1390
* descriptors", most devices never use more than 16 bits.
1391
* One model of UPS is claimed to report "LINEV" as a 32-bit field.
1392
* Search linux-kernel and linux-usb-devel archives for "hid-core extract".
1393
*/
1394
1395
static u32 __extract(u8 *report, unsigned offset, int n)
1396
{
1397
unsigned int idx = offset / 8;
1398
unsigned int bit_nr = 0;
1399
unsigned int bit_shift = offset % 8;
1400
int bits_to_copy = 8 - bit_shift;
1401
u32 value = 0;
1402
u32 mask = n < 32 ? (1U << n) - 1 : ~0U;
1403
1404
while (n > 0) {
1405
value |= ((u32)report[idx] >> bit_shift) << bit_nr;
1406
n -= bits_to_copy;
1407
bit_nr += bits_to_copy;
1408
bits_to_copy = 8;
1409
bit_shift = 0;
1410
idx++;
1411
}
1412
1413
return value & mask;
1414
}
1415
1416
u32 hid_field_extract(const struct hid_device *hid, u8 *report,
1417
unsigned offset, unsigned n)
1418
{
1419
if (n > 32) {
1420
hid_warn_once(hid, "%s() called with n (%d) > 32! (%s)\n",
1421
__func__, n, current->comm);
1422
n = 32;
1423
}
1424
1425
return __extract(report, offset, n);
1426
}
1427
EXPORT_SYMBOL_GPL(hid_field_extract);
1428
1429
/*
1430
* "implement" : set bits in a little endian bit stream.
1431
* Same concepts as "extract" (see comments above).
1432
* The data mangled in the bit stream remains in little endian
1433
* order the whole time. It make more sense to talk about
1434
* endianness of register values by considering a register
1435
* a "cached" copy of the little endian bit stream.
1436
*/
1437
1438
static void __implement(u8 *report, unsigned offset, int n, u32 value)
1439
{
1440
unsigned int idx = offset / 8;
1441
unsigned int bit_shift = offset % 8;
1442
int bits_to_set = 8 - bit_shift;
1443
1444
while (n - bits_to_set >= 0) {
1445
report[idx] &= ~(0xff << bit_shift);
1446
report[idx] |= value << bit_shift;
1447
value >>= bits_to_set;
1448
n -= bits_to_set;
1449
bits_to_set = 8;
1450
bit_shift = 0;
1451
idx++;
1452
}
1453
1454
/* last nibble */
1455
if (n) {
1456
u8 bit_mask = ((1U << n) - 1);
1457
report[idx] &= ~(bit_mask << bit_shift);
1458
report[idx] |= value << bit_shift;
1459
}
1460
}
1461
1462
static void implement(const struct hid_device *hid, u8 *report,
1463
unsigned offset, unsigned n, u32 value)
1464
{
1465
if (unlikely(n > 32)) {
1466
hid_warn(hid, "%s() called with n (%d) > 32! (%s)\n",
1467
__func__, n, current->comm);
1468
n = 32;
1469
} else if (n < 32) {
1470
u32 m = (1U << n) - 1;
1471
1472
if (unlikely(value > m)) {
1473
hid_warn(hid,
1474
"%s() called with too large value %d (n: %d)! (%s)\n",
1475
__func__, value, n, current->comm);
1476
value &= m;
1477
}
1478
}
1479
1480
__implement(report, offset, n, value);
1481
}
1482
1483
/*
1484
* Search an array for a value.
1485
*/
1486
1487
static int search(__s32 *array, __s32 value, unsigned n)
1488
{
1489
while (n--) {
1490
if (*array++ == value)
1491
return 0;
1492
}
1493
return -1;
1494
}
1495
1496
/**
1497
* hid_match_report - check if driver's raw_event should be called
1498
*
1499
* @hid: hid device
1500
* @report: hid report to match against
1501
*
1502
* compare hid->driver->report_table->report_type to report->type
1503
*/
1504
static int hid_match_report(struct hid_device *hid, struct hid_report *report)
1505
{
1506
const struct hid_report_id *id = hid->driver->report_table;
1507
1508
if (!id) /* NULL means all */
1509
return 1;
1510
1511
for (; id->report_type != HID_TERMINATOR; id++)
1512
if (id->report_type == HID_ANY_ID ||
1513
id->report_type == report->type)
1514
return 1;
1515
return 0;
1516
}
1517
1518
/**
1519
* hid_match_usage - check if driver's event should be called
1520
*
1521
* @hid: hid device
1522
* @usage: usage to match against
1523
*
1524
* compare hid->driver->usage_table->usage_{type,code} to
1525
* usage->usage_{type,code}
1526
*/
1527
static int hid_match_usage(struct hid_device *hid, struct hid_usage *usage)
1528
{
1529
const struct hid_usage_id *id = hid->driver->usage_table;
1530
1531
if (!id) /* NULL means all */
1532
return 1;
1533
1534
for (; id->usage_type != HID_ANY_ID - 1; id++)
1535
if ((id->usage_hid == HID_ANY_ID ||
1536
id->usage_hid == usage->hid) &&
1537
(id->usage_type == HID_ANY_ID ||
1538
id->usage_type == usage->type) &&
1539
(id->usage_code == HID_ANY_ID ||
1540
id->usage_code == usage->code))
1541
return 1;
1542
return 0;
1543
}
1544
1545
static void hid_process_event(struct hid_device *hid, struct hid_field *field,
1546
struct hid_usage *usage, __s32 value, int interrupt)
1547
{
1548
struct hid_driver *hdrv = hid->driver;
1549
int ret;
1550
1551
if (!list_empty(&hid->debug_list))
1552
hid_dump_input(hid, usage, value);
1553
1554
if (hdrv && hdrv->event && hid_match_usage(hid, usage)) {
1555
ret = hdrv->event(hid, field, usage, value);
1556
if (ret != 0) {
1557
if (ret < 0)
1558
hid_err(hid, "%s's event failed with %d\n",
1559
hdrv->name, ret);
1560
return;
1561
}
1562
}
1563
1564
if (hid->claimed & HID_CLAIMED_INPUT)
1565
hidinput_hid_event(hid, field, usage, value);
1566
if (hid->claimed & HID_CLAIMED_HIDDEV && interrupt && hid->hiddev_hid_event)
1567
hid->hiddev_hid_event(hid, field, usage, value);
1568
}
1569
1570
/*
1571
* Checks if the given value is valid within this field
1572
*/
1573
static inline int hid_array_value_is_valid(struct hid_field *field,
1574
__s32 value)
1575
{
1576
__s32 min = field->logical_minimum;
1577
1578
/*
1579
* Value needs to be between logical min and max, and
1580
* (value - min) is used as an index in the usage array.
1581
* This array is of size field->maxusage
1582
*/
1583
return value >= min &&
1584
value <= field->logical_maximum &&
1585
value - min < field->maxusage;
1586
}
1587
1588
/*
1589
* Fetch the field from the data. The field content is stored for next
1590
* report processing (we do differential reporting to the layer).
1591
*/
1592
static void hid_input_fetch_field(struct hid_device *hid,
1593
struct hid_field *field,
1594
__u8 *data)
1595
{
1596
unsigned n;
1597
unsigned count = field->report_count;
1598
unsigned offset = field->report_offset;
1599
unsigned size = field->report_size;
1600
__s32 min = field->logical_minimum;
1601
__s32 *value;
1602
1603
value = field->new_value;
1604
memset(value, 0, count * sizeof(__s32));
1605
field->ignored = false;
1606
1607
for (n = 0; n < count; n++) {
1608
1609
value[n] = min < 0 ?
1610
snto32(hid_field_extract(hid, data, offset + n * size,
1611
size), size) :
1612
hid_field_extract(hid, data, offset + n * size, size);
1613
1614
/* Ignore report if ErrorRollOver */
1615
if (!(field->flags & HID_MAIN_ITEM_VARIABLE) &&
1616
hid_array_value_is_valid(field, value[n]) &&
1617
field->usage[value[n] - min].hid == HID_UP_KEYBOARD + 1) {
1618
field->ignored = true;
1619
return;
1620
}
1621
}
1622
}
1623
1624
/*
1625
* Process a received variable field.
1626
*/
1627
1628
static void hid_input_var_field(struct hid_device *hid,
1629
struct hid_field *field,
1630
int interrupt)
1631
{
1632
unsigned int count = field->report_count;
1633
__s32 *value = field->new_value;
1634
unsigned int n;
1635
1636
for (n = 0; n < count; n++)
1637
hid_process_event(hid,
1638
field,
1639
&field->usage[n],
1640
value[n],
1641
interrupt);
1642
1643
memcpy(field->value, value, count * sizeof(__s32));
1644
}
1645
1646
/*
1647
* Process a received array field. The field content is stored for
1648
* next report processing (we do differential reporting to the layer).
1649
*/
1650
1651
static void hid_input_array_field(struct hid_device *hid,
1652
struct hid_field *field,
1653
int interrupt)
1654
{
1655
unsigned int n;
1656
unsigned int count = field->report_count;
1657
__s32 min = field->logical_minimum;
1658
__s32 *value;
1659
1660
value = field->new_value;
1661
1662
/* ErrorRollOver */
1663
if (field->ignored)
1664
return;
1665
1666
for (n = 0; n < count; n++) {
1667
if (hid_array_value_is_valid(field, field->value[n]) &&
1668
search(value, field->value[n], count))
1669
hid_process_event(hid,
1670
field,
1671
&field->usage[field->value[n] - min],
1672
0,
1673
interrupt);
1674
1675
if (hid_array_value_is_valid(field, value[n]) &&
1676
search(field->value, value[n], count))
1677
hid_process_event(hid,
1678
field,
1679
&field->usage[value[n] - min],
1680
1,
1681
interrupt);
1682
}
1683
1684
memcpy(field->value, value, count * sizeof(__s32));
1685
}
1686
1687
/*
1688
* Analyse a received report, and fetch the data from it. The field
1689
* content is stored for next report processing (we do differential
1690
* reporting to the layer).
1691
*/
1692
static void hid_process_report(struct hid_device *hid,
1693
struct hid_report *report,
1694
__u8 *data,
1695
int interrupt)
1696
{
1697
unsigned int a;
1698
struct hid_field_entry *entry;
1699
struct hid_field *field;
1700
1701
/* first retrieve all incoming values in data */
1702
for (a = 0; a < report->maxfield; a++)
1703
hid_input_fetch_field(hid, report->field[a], data);
1704
1705
if (!list_empty(&report->field_entry_list)) {
1706
/* INPUT_REPORT, we have a priority list of fields */
1707
list_for_each_entry(entry,
1708
&report->field_entry_list,
1709
list) {
1710
field = entry->field;
1711
1712
if (field->flags & HID_MAIN_ITEM_VARIABLE)
1713
hid_process_event(hid,
1714
field,
1715
&field->usage[entry->index],
1716
field->new_value[entry->index],
1717
interrupt);
1718
else
1719
hid_input_array_field(hid, field, interrupt);
1720
}
1721
1722
/* we need to do the memcpy at the end for var items */
1723
for (a = 0; a < report->maxfield; a++) {
1724
field = report->field[a];
1725
1726
if (field->flags & HID_MAIN_ITEM_VARIABLE)
1727
memcpy(field->value, field->new_value,
1728
field->report_count * sizeof(__s32));
1729
}
1730
} else {
1731
/* FEATURE_REPORT, regular processing */
1732
for (a = 0; a < report->maxfield; a++) {
1733
field = report->field[a];
1734
1735
if (field->flags & HID_MAIN_ITEM_VARIABLE)
1736
hid_input_var_field(hid, field, interrupt);
1737
else
1738
hid_input_array_field(hid, field, interrupt);
1739
}
1740
}
1741
}
1742
1743
/*
1744
* Insert a given usage_index in a field in the list
1745
* of processed usages in the report.
1746
*
1747
* The elements of lower priority score are processed
1748
* first.
1749
*/
1750
static void __hid_insert_field_entry(struct hid_device *hid,
1751
struct hid_report *report,
1752
struct hid_field_entry *entry,
1753
struct hid_field *field,
1754
unsigned int usage_index)
1755
{
1756
struct hid_field_entry *next;
1757
1758
entry->field = field;
1759
entry->index = usage_index;
1760
entry->priority = field->usages_priorities[usage_index];
1761
1762
/* insert the element at the correct position */
1763
list_for_each_entry(next,
1764
&report->field_entry_list,
1765
list) {
1766
/*
1767
* the priority of our element is strictly higher
1768
* than the next one, insert it before
1769
*/
1770
if (entry->priority > next->priority) {
1771
list_add_tail(&entry->list, &next->list);
1772
return;
1773
}
1774
}
1775
1776
/* lowest priority score: insert at the end */
1777
list_add_tail(&entry->list, &report->field_entry_list);
1778
}
1779
1780
static void hid_report_process_ordering(struct hid_device *hid,
1781
struct hid_report *report)
1782
{
1783
struct hid_field *field;
1784
struct hid_field_entry *entries;
1785
unsigned int a, u, usages;
1786
unsigned int count = 0;
1787
1788
/* count the number of individual fields in the report */
1789
for (a = 0; a < report->maxfield; a++) {
1790
field = report->field[a];
1791
1792
if (field->flags & HID_MAIN_ITEM_VARIABLE)
1793
count += field->report_count;
1794
else
1795
count++;
1796
}
1797
1798
/* allocate the memory to process the fields */
1799
entries = kcalloc(count, sizeof(*entries), GFP_KERNEL);
1800
if (!entries)
1801
return;
1802
1803
report->field_entries = entries;
1804
1805
/*
1806
* walk through all fields in the report and
1807
* store them by priority order in report->field_entry_list
1808
*
1809
* - Var elements are individualized (field + usage_index)
1810
* - Arrays are taken as one, we can not chose an order for them
1811
*/
1812
usages = 0;
1813
for (a = 0; a < report->maxfield; a++) {
1814
field = report->field[a];
1815
1816
if (field->flags & HID_MAIN_ITEM_VARIABLE) {
1817
for (u = 0; u < field->report_count; u++) {
1818
__hid_insert_field_entry(hid, report,
1819
&entries[usages],
1820
field, u);
1821
usages++;
1822
}
1823
} else {
1824
__hid_insert_field_entry(hid, report, &entries[usages],
1825
field, 0);
1826
usages++;
1827
}
1828
}
1829
}
1830
1831
static void hid_process_ordering(struct hid_device *hid)
1832
{
1833
struct hid_report *report;
1834
struct hid_report_enum *report_enum = &hid->report_enum[HID_INPUT_REPORT];
1835
1836
list_for_each_entry(report, &report_enum->report_list, list)
1837
hid_report_process_ordering(hid, report);
1838
}
1839
1840
/*
1841
* Output the field into the report.
1842
*/
1843
1844
static void hid_output_field(const struct hid_device *hid,
1845
struct hid_field *field, __u8 *data)
1846
{
1847
unsigned count = field->report_count;
1848
unsigned offset = field->report_offset;
1849
unsigned size = field->report_size;
1850
unsigned n;
1851
1852
for (n = 0; n < count; n++) {
1853
if (field->logical_minimum < 0) /* signed values */
1854
implement(hid, data, offset + n * size, size,
1855
s32ton(field->value[n], size));
1856
else /* unsigned values */
1857
implement(hid, data, offset + n * size, size,
1858
field->value[n]);
1859
}
1860
}
1861
1862
/*
1863
* Compute the size of a report.
1864
*/
1865
static size_t hid_compute_report_size(struct hid_report *report)
1866
{
1867
if (report->size)
1868
return ((report->size - 1) >> 3) + 1;
1869
1870
return 0;
1871
}
1872
1873
/*
1874
* Create a report. 'data' has to be allocated using
1875
* hid_alloc_report_buf() so that it has proper size.
1876
*/
1877
1878
void hid_output_report(struct hid_report *report, __u8 *data)
1879
{
1880
unsigned n;
1881
1882
if (report->id > 0)
1883
*data++ = report->id;
1884
1885
memset(data, 0, hid_compute_report_size(report));
1886
for (n = 0; n < report->maxfield; n++)
1887
hid_output_field(report->device, report->field[n], data);
1888
}
1889
EXPORT_SYMBOL_GPL(hid_output_report);
1890
1891
/*
1892
* Allocator for buffer that is going to be passed to hid_output_report()
1893
*/
1894
u8 *hid_alloc_report_buf(struct hid_report *report, gfp_t flags)
1895
{
1896
/*
1897
* 7 extra bytes are necessary to achieve proper functionality
1898
* of implement() working on 8 byte chunks
1899
* 1 extra byte for the report ID if it is null (not used) so
1900
* we can reserve that extra byte in the first position of the buffer
1901
* when sending it to .raw_request()
1902
*/
1903
1904
u32 len = hid_report_len(report) + 7 + (report->id == 0);
1905
1906
return kzalloc(len, flags);
1907
}
1908
EXPORT_SYMBOL_GPL(hid_alloc_report_buf);
1909
1910
/*
1911
* Set a field value. The report this field belongs to has to be
1912
* created and transferred to the device, to set this value in the
1913
* device.
1914
*/
1915
1916
int hid_set_field(struct hid_field *field, unsigned offset, __s32 value)
1917
{
1918
unsigned size;
1919
1920
if (!field)
1921
return -1;
1922
1923
size = field->report_size;
1924
1925
hid_dump_input(field->report->device, field->usage + offset, value);
1926
1927
if (offset >= field->report_count) {
1928
hid_err(field->report->device, "offset (%d) exceeds report_count (%d)\n",
1929
offset, field->report_count);
1930
return -1;
1931
}
1932
if (field->logical_minimum < 0) {
1933
if (value != snto32(s32ton(value, size), size)) {
1934
hid_err(field->report->device, "value %d is out of range\n", value);
1935
return -1;
1936
}
1937
}
1938
field->value[offset] = value;
1939
return 0;
1940
}
1941
EXPORT_SYMBOL_GPL(hid_set_field);
1942
1943
struct hid_field *hid_find_field(struct hid_device *hdev, unsigned int report_type,
1944
unsigned int application, unsigned int usage)
1945
{
1946
struct list_head *report_list = &hdev->report_enum[report_type].report_list;
1947
struct hid_report *report;
1948
int i, j;
1949
1950
list_for_each_entry(report, report_list, list) {
1951
if (report->application != application)
1952
continue;
1953
1954
for (i = 0; i < report->maxfield; i++) {
1955
struct hid_field *field = report->field[i];
1956
1957
for (j = 0; j < field->maxusage; j++) {
1958
if (field->usage[j].hid == usage)
1959
return field;
1960
}
1961
}
1962
}
1963
1964
return NULL;
1965
}
1966
EXPORT_SYMBOL_GPL(hid_find_field);
1967
1968
static struct hid_report *hid_get_report(struct hid_report_enum *report_enum,
1969
const u8 *data)
1970
{
1971
struct hid_report *report;
1972
unsigned int n = 0; /* Normally report number is 0 */
1973
1974
/* Device uses numbered reports, data[0] is report number */
1975
if (report_enum->numbered)
1976
n = *data;
1977
1978
report = report_enum->report_id_hash[n];
1979
if (report == NULL)
1980
dbg_hid("undefined report_id %u received\n", n);
1981
1982
return report;
1983
}
1984
1985
/*
1986
* Implement a generic .request() callback, using .raw_request()
1987
* DO NOT USE in hid drivers directly, but through hid_hw_request instead.
1988
*/
1989
int __hid_request(struct hid_device *hid, struct hid_report *report,
1990
enum hid_class_request reqtype)
1991
{
1992
char *buf, *data_buf;
1993
int ret;
1994
u32 len;
1995
1996
buf = hid_alloc_report_buf(report, GFP_KERNEL);
1997
if (!buf)
1998
return -ENOMEM;
1999
2000
data_buf = buf;
2001
len = hid_report_len(report);
2002
2003
if (report->id == 0) {
2004
/* reserve the first byte for the report ID */
2005
data_buf++;
2006
len++;
2007
}
2008
2009
if (reqtype == HID_REQ_SET_REPORT)
2010
hid_output_report(report, data_buf);
2011
2012
ret = hid_hw_raw_request(hid, report->id, buf, len, report->type, reqtype);
2013
if (ret < 0) {
2014
dbg_hid("unable to complete request: %d\n", ret);
2015
goto out;
2016
}
2017
2018
if (reqtype == HID_REQ_GET_REPORT)
2019
hid_input_report(hid, report->type, buf, ret, 0);
2020
2021
ret = 0;
2022
2023
out:
2024
kfree(buf);
2025
return ret;
2026
}
2027
EXPORT_SYMBOL_GPL(__hid_request);
2028
2029
int hid_report_raw_event(struct hid_device *hid, enum hid_report_type type, u8 *data, u32 size,
2030
int interrupt)
2031
{
2032
struct hid_report_enum *report_enum = hid->report_enum + type;
2033
struct hid_report *report;
2034
struct hid_driver *hdrv;
2035
int max_buffer_size = HID_MAX_BUFFER_SIZE;
2036
u32 rsize, csize = size;
2037
u8 *cdata = data;
2038
int ret = 0;
2039
2040
report = hid_get_report(report_enum, data);
2041
if (!report)
2042
goto out;
2043
2044
if (report_enum->numbered) {
2045
cdata++;
2046
csize--;
2047
}
2048
2049
rsize = hid_compute_report_size(report);
2050
2051
if (hid->ll_driver->max_buffer_size)
2052
max_buffer_size = hid->ll_driver->max_buffer_size;
2053
2054
if (report_enum->numbered && rsize >= max_buffer_size)
2055
rsize = max_buffer_size - 1;
2056
else if (rsize > max_buffer_size)
2057
rsize = max_buffer_size;
2058
2059
if (csize < rsize) {
2060
dbg_hid("report %d is too short, (%d < %d)\n", report->id,
2061
csize, rsize);
2062
memset(cdata + csize, 0, rsize - csize);
2063
}
2064
2065
if ((hid->claimed & HID_CLAIMED_HIDDEV) && hid->hiddev_report_event)
2066
hid->hiddev_report_event(hid, report);
2067
if (hid->claimed & HID_CLAIMED_HIDRAW) {
2068
ret = hidraw_report_event(hid, data, size);
2069
if (ret)
2070
goto out;
2071
}
2072
2073
if (hid->claimed != HID_CLAIMED_HIDRAW && report->maxfield) {
2074
hid_process_report(hid, report, cdata, interrupt);
2075
hdrv = hid->driver;
2076
if (hdrv && hdrv->report)
2077
hdrv->report(hid, report);
2078
}
2079
2080
if (hid->claimed & HID_CLAIMED_INPUT)
2081
hidinput_report_event(hid, report);
2082
out:
2083
return ret;
2084
}
2085
EXPORT_SYMBOL_GPL(hid_report_raw_event);
2086
2087
2088
static int __hid_input_report(struct hid_device *hid, enum hid_report_type type,
2089
u8 *data, u32 size, int interrupt, u64 source, bool from_bpf,
2090
bool lock_already_taken)
2091
{
2092
struct hid_report_enum *report_enum;
2093
struct hid_driver *hdrv;
2094
struct hid_report *report;
2095
int ret = 0;
2096
2097
if (!hid)
2098
return -ENODEV;
2099
2100
ret = down_trylock(&hid->driver_input_lock);
2101
if (lock_already_taken && !ret) {
2102
up(&hid->driver_input_lock);
2103
return -EINVAL;
2104
} else if (!lock_already_taken && ret) {
2105
return -EBUSY;
2106
}
2107
2108
if (!hid->driver) {
2109
ret = -ENODEV;
2110
goto unlock;
2111
}
2112
report_enum = hid->report_enum + type;
2113
hdrv = hid->driver;
2114
2115
data = dispatch_hid_bpf_device_event(hid, type, data, &size, interrupt, source, from_bpf);
2116
if (IS_ERR(data)) {
2117
ret = PTR_ERR(data);
2118
goto unlock;
2119
}
2120
2121
if (!size) {
2122
dbg_hid("empty report\n");
2123
ret = -1;
2124
goto unlock;
2125
}
2126
2127
/* Avoid unnecessary overhead if debugfs is disabled */
2128
if (!list_empty(&hid->debug_list))
2129
hid_dump_report(hid, type, data, size);
2130
2131
report = hid_get_report(report_enum, data);
2132
2133
if (!report) {
2134
ret = -1;
2135
goto unlock;
2136
}
2137
2138
if (hdrv && hdrv->raw_event && hid_match_report(hid, report)) {
2139
ret = hdrv->raw_event(hid, report, data, size);
2140
if (ret < 0)
2141
goto unlock;
2142
}
2143
2144
ret = hid_report_raw_event(hid, type, data, size, interrupt);
2145
2146
unlock:
2147
if (!lock_already_taken)
2148
up(&hid->driver_input_lock);
2149
return ret;
2150
}
2151
2152
/**
2153
* hid_input_report - report data from lower layer (usb, bt...)
2154
*
2155
* @hid: hid device
2156
* @type: HID report type (HID_*_REPORT)
2157
* @data: report contents
2158
* @size: size of data parameter
2159
* @interrupt: distinguish between interrupt and control transfers
2160
*
2161
* This is data entry for lower layers.
2162
*/
2163
int hid_input_report(struct hid_device *hid, enum hid_report_type type, u8 *data, u32 size,
2164
int interrupt)
2165
{
2166
return __hid_input_report(hid, type, data, size, interrupt, 0,
2167
false, /* from_bpf */
2168
false /* lock_already_taken */);
2169
}
2170
EXPORT_SYMBOL_GPL(hid_input_report);
2171
2172
bool hid_match_one_id(const struct hid_device *hdev,
2173
const struct hid_device_id *id)
2174
{
2175
return (id->bus == HID_BUS_ANY || id->bus == hdev->bus) &&
2176
(id->group == HID_GROUP_ANY || id->group == hdev->group) &&
2177
(id->vendor == HID_ANY_ID || id->vendor == hdev->vendor) &&
2178
(id->product == HID_ANY_ID || id->product == hdev->product);
2179
}
2180
2181
const struct hid_device_id *hid_match_id(const struct hid_device *hdev,
2182
const struct hid_device_id *id)
2183
{
2184
for (; id->bus; id++)
2185
if (hid_match_one_id(hdev, id))
2186
return id;
2187
2188
return NULL;
2189
}
2190
EXPORT_SYMBOL_GPL(hid_match_id);
2191
2192
static const struct hid_device_id hid_hiddev_list[] = {
2193
{ HID_USB_DEVICE(USB_VENDOR_ID_MGE, USB_DEVICE_ID_MGE_UPS) },
2194
{ HID_USB_DEVICE(USB_VENDOR_ID_MGE, USB_DEVICE_ID_MGE_UPS1) },
2195
{ }
2196
};
2197
2198
static bool hid_hiddev(struct hid_device *hdev)
2199
{
2200
return !!hid_match_id(hdev, hid_hiddev_list);
2201
}
2202
2203
2204
static ssize_t
2205
report_descriptor_read(struct file *filp, struct kobject *kobj,
2206
const struct bin_attribute *attr,
2207
char *buf, loff_t off, size_t count)
2208
{
2209
struct device *dev = kobj_to_dev(kobj);
2210
struct hid_device *hdev = to_hid_device(dev);
2211
2212
if (off >= hdev->rsize)
2213
return 0;
2214
2215
if (off + count > hdev->rsize)
2216
count = hdev->rsize - off;
2217
2218
memcpy(buf, hdev->rdesc + off, count);
2219
2220
return count;
2221
}
2222
2223
static ssize_t
2224
country_show(struct device *dev, struct device_attribute *attr,
2225
char *buf)
2226
{
2227
struct hid_device *hdev = to_hid_device(dev);
2228
2229
return sprintf(buf, "%02x\n", hdev->country & 0xff);
2230
}
2231
2232
static const BIN_ATTR_RO(report_descriptor, HID_MAX_DESCRIPTOR_SIZE);
2233
2234
static const DEVICE_ATTR_RO(country);
2235
2236
int hid_connect(struct hid_device *hdev, unsigned int connect_mask)
2237
{
2238
static const char *types[] = { "Device", "Pointer", "Mouse", "Device",
2239
"Joystick", "Gamepad", "Keyboard", "Keypad",
2240
"Multi-Axis Controller"
2241
};
2242
const char *type, *bus;
2243
char buf[64] = "";
2244
unsigned int i;
2245
int len;
2246
int ret;
2247
2248
ret = hid_bpf_connect_device(hdev);
2249
if (ret)
2250
return ret;
2251
2252
if (hdev->quirks & HID_QUIRK_HIDDEV_FORCE)
2253
connect_mask |= (HID_CONNECT_HIDDEV_FORCE | HID_CONNECT_HIDDEV);
2254
if (hdev->quirks & HID_QUIRK_HIDINPUT_FORCE)
2255
connect_mask |= HID_CONNECT_HIDINPUT_FORCE;
2256
if (hdev->bus != BUS_USB)
2257
connect_mask &= ~HID_CONNECT_HIDDEV;
2258
if (hid_hiddev(hdev))
2259
connect_mask |= HID_CONNECT_HIDDEV_FORCE;
2260
2261
if ((connect_mask & HID_CONNECT_HIDINPUT) && !hidinput_connect(hdev,
2262
connect_mask & HID_CONNECT_HIDINPUT_FORCE))
2263
hdev->claimed |= HID_CLAIMED_INPUT;
2264
2265
if ((connect_mask & HID_CONNECT_HIDDEV) && hdev->hiddev_connect &&
2266
!hdev->hiddev_connect(hdev,
2267
connect_mask & HID_CONNECT_HIDDEV_FORCE))
2268
hdev->claimed |= HID_CLAIMED_HIDDEV;
2269
if ((connect_mask & HID_CONNECT_HIDRAW) && !hidraw_connect(hdev))
2270
hdev->claimed |= HID_CLAIMED_HIDRAW;
2271
2272
if (connect_mask & HID_CONNECT_DRIVER)
2273
hdev->claimed |= HID_CLAIMED_DRIVER;
2274
2275
/* Drivers with the ->raw_event callback set are not required to connect
2276
* to any other listener. */
2277
if (!hdev->claimed && !hdev->driver->raw_event) {
2278
hid_err(hdev, "device has no listeners, quitting\n");
2279
return -ENODEV;
2280
}
2281
2282
hid_process_ordering(hdev);
2283
2284
if ((hdev->claimed & HID_CLAIMED_INPUT) &&
2285
(connect_mask & HID_CONNECT_FF) && hdev->ff_init)
2286
hdev->ff_init(hdev);
2287
2288
len = 0;
2289
if (hdev->claimed & HID_CLAIMED_INPUT)
2290
len += sprintf(buf + len, "input");
2291
if (hdev->claimed & HID_CLAIMED_HIDDEV)
2292
len += sprintf(buf + len, "%shiddev%d", len ? "," : "",
2293
((struct hiddev *)hdev->hiddev)->minor);
2294
if (hdev->claimed & HID_CLAIMED_HIDRAW)
2295
len += sprintf(buf + len, "%shidraw%d", len ? "," : "",
2296
((struct hidraw *)hdev->hidraw)->minor);
2297
2298
type = "Device";
2299
for (i = 0; i < hdev->maxcollection; i++) {
2300
struct hid_collection *col = &hdev->collection[i];
2301
if (col->type == HID_COLLECTION_APPLICATION &&
2302
(col->usage & HID_USAGE_PAGE) == HID_UP_GENDESK &&
2303
(col->usage & 0xffff) < ARRAY_SIZE(types)) {
2304
type = types[col->usage & 0xffff];
2305
break;
2306
}
2307
}
2308
2309
switch (hdev->bus) {
2310
case BUS_USB:
2311
bus = "USB";
2312
break;
2313
case BUS_BLUETOOTH:
2314
bus = "BLUETOOTH";
2315
break;
2316
case BUS_I2C:
2317
bus = "I2C";
2318
break;
2319
case BUS_SDW:
2320
bus = "SOUNDWIRE";
2321
break;
2322
case BUS_VIRTUAL:
2323
bus = "VIRTUAL";
2324
break;
2325
case BUS_INTEL_ISHTP:
2326
case BUS_AMD_SFH:
2327
bus = "SENSOR HUB";
2328
break;
2329
default:
2330
bus = "<UNKNOWN>";
2331
}
2332
2333
ret = device_create_file(&hdev->dev, &dev_attr_country);
2334
if (ret)
2335
hid_warn(hdev,
2336
"can't create sysfs country code attribute err: %d\n", ret);
2337
2338
hid_info(hdev, "%s: %s HID v%x.%02x %s [%s] on %s\n",
2339
buf, bus, hdev->version >> 8, hdev->version & 0xff,
2340
type, hdev->name, hdev->phys);
2341
2342
return 0;
2343
}
2344
EXPORT_SYMBOL_GPL(hid_connect);
2345
2346
void hid_disconnect(struct hid_device *hdev)
2347
{
2348
device_remove_file(&hdev->dev, &dev_attr_country);
2349
if (hdev->claimed & HID_CLAIMED_INPUT)
2350
hidinput_disconnect(hdev);
2351
if (hdev->claimed & HID_CLAIMED_HIDDEV)
2352
hdev->hiddev_disconnect(hdev);
2353
if (hdev->claimed & HID_CLAIMED_HIDRAW)
2354
hidraw_disconnect(hdev);
2355
hdev->claimed = 0;
2356
2357
hid_bpf_disconnect_device(hdev);
2358
}
2359
EXPORT_SYMBOL_GPL(hid_disconnect);
2360
2361
/**
2362
* hid_hw_start - start underlying HW
2363
* @hdev: hid device
2364
* @connect_mask: which outputs to connect, see HID_CONNECT_*
2365
*
2366
* Call this in probe function *after* hid_parse. This will setup HW
2367
* buffers and start the device (if not defeirred to device open).
2368
* hid_hw_stop must be called if this was successful.
2369
*/
2370
int hid_hw_start(struct hid_device *hdev, unsigned int connect_mask)
2371
{
2372
int error;
2373
2374
error = hdev->ll_driver->start(hdev);
2375
if (error)
2376
return error;
2377
2378
if (connect_mask) {
2379
error = hid_connect(hdev, connect_mask);
2380
if (error) {
2381
hdev->ll_driver->stop(hdev);
2382
return error;
2383
}
2384
}
2385
2386
return 0;
2387
}
2388
EXPORT_SYMBOL_GPL(hid_hw_start);
2389
2390
/**
2391
* hid_hw_stop - stop underlying HW
2392
* @hdev: hid device
2393
*
2394
* This is usually called from remove function or from probe when something
2395
* failed and hid_hw_start was called already.
2396
*/
2397
void hid_hw_stop(struct hid_device *hdev)
2398
{
2399
hid_disconnect(hdev);
2400
hdev->ll_driver->stop(hdev);
2401
}
2402
EXPORT_SYMBOL_GPL(hid_hw_stop);
2403
2404
/**
2405
* hid_hw_open - signal underlying HW to start delivering events
2406
* @hdev: hid device
2407
*
2408
* Tell underlying HW to start delivering events from the device.
2409
* This function should be called sometime after successful call
2410
* to hid_hw_start().
2411
*/
2412
int hid_hw_open(struct hid_device *hdev)
2413
{
2414
int ret;
2415
2416
ret = mutex_lock_killable(&hdev->ll_open_lock);
2417
if (ret)
2418
return ret;
2419
2420
if (!hdev->ll_open_count++) {
2421
ret = hdev->ll_driver->open(hdev);
2422
if (ret)
2423
hdev->ll_open_count--;
2424
2425
if (hdev->driver->on_hid_hw_open)
2426
hdev->driver->on_hid_hw_open(hdev);
2427
}
2428
2429
mutex_unlock(&hdev->ll_open_lock);
2430
return ret;
2431
}
2432
EXPORT_SYMBOL_GPL(hid_hw_open);
2433
2434
/**
2435
* hid_hw_close - signal underlaying HW to stop delivering events
2436
*
2437
* @hdev: hid device
2438
*
2439
* This function indicates that we are not interested in the events
2440
* from this device anymore. Delivery of events may or may not stop,
2441
* depending on the number of users still outstanding.
2442
*/
2443
void hid_hw_close(struct hid_device *hdev)
2444
{
2445
mutex_lock(&hdev->ll_open_lock);
2446
if (!--hdev->ll_open_count) {
2447
hdev->ll_driver->close(hdev);
2448
2449
if (hdev->driver->on_hid_hw_close)
2450
hdev->driver->on_hid_hw_close(hdev);
2451
}
2452
mutex_unlock(&hdev->ll_open_lock);
2453
}
2454
EXPORT_SYMBOL_GPL(hid_hw_close);
2455
2456
/**
2457
* hid_hw_request - send report request to device
2458
*
2459
* @hdev: hid device
2460
* @report: report to send
2461
* @reqtype: hid request type
2462
*/
2463
void hid_hw_request(struct hid_device *hdev,
2464
struct hid_report *report, enum hid_class_request reqtype)
2465
{
2466
if (hdev->ll_driver->request)
2467
return hdev->ll_driver->request(hdev, report, reqtype);
2468
2469
__hid_request(hdev, report, reqtype);
2470
}
2471
EXPORT_SYMBOL_GPL(hid_hw_request);
2472
2473
int __hid_hw_raw_request(struct hid_device *hdev,
2474
unsigned char reportnum, __u8 *buf,
2475
size_t len, enum hid_report_type rtype,
2476
enum hid_class_request reqtype,
2477
u64 source, bool from_bpf)
2478
{
2479
unsigned int max_buffer_size = HID_MAX_BUFFER_SIZE;
2480
int ret;
2481
2482
if (hdev->ll_driver->max_buffer_size)
2483
max_buffer_size = hdev->ll_driver->max_buffer_size;
2484
2485
if (len < 1 || len > max_buffer_size || !buf)
2486
return -EINVAL;
2487
2488
ret = dispatch_hid_bpf_raw_requests(hdev, reportnum, buf, len, rtype,
2489
reqtype, source, from_bpf);
2490
if (ret)
2491
return ret;
2492
2493
return hdev->ll_driver->raw_request(hdev, reportnum, buf, len,
2494
rtype, reqtype);
2495
}
2496
2497
/**
2498
* hid_hw_raw_request - send report request to device
2499
*
2500
* @hdev: hid device
2501
* @reportnum: report ID
2502
* @buf: in/out data to transfer
2503
* @len: length of buf
2504
* @rtype: HID report type
2505
* @reqtype: HID_REQ_GET_REPORT or HID_REQ_SET_REPORT
2506
*
2507
* Return: count of data transferred, negative if error
2508
*
2509
* Same behavior as hid_hw_request, but with raw buffers instead.
2510
*/
2511
int hid_hw_raw_request(struct hid_device *hdev,
2512
unsigned char reportnum, __u8 *buf,
2513
size_t len, enum hid_report_type rtype, enum hid_class_request reqtype)
2514
{
2515
return __hid_hw_raw_request(hdev, reportnum, buf, len, rtype, reqtype, 0, false);
2516
}
2517
EXPORT_SYMBOL_GPL(hid_hw_raw_request);
2518
2519
int __hid_hw_output_report(struct hid_device *hdev, __u8 *buf, size_t len, u64 source,
2520
bool from_bpf)
2521
{
2522
unsigned int max_buffer_size = HID_MAX_BUFFER_SIZE;
2523
int ret;
2524
2525
if (hdev->ll_driver->max_buffer_size)
2526
max_buffer_size = hdev->ll_driver->max_buffer_size;
2527
2528
if (len < 1 || len > max_buffer_size || !buf)
2529
return -EINVAL;
2530
2531
ret = dispatch_hid_bpf_output_report(hdev, buf, len, source, from_bpf);
2532
if (ret)
2533
return ret;
2534
2535
if (hdev->ll_driver->output_report)
2536
return hdev->ll_driver->output_report(hdev, buf, len);
2537
2538
return -ENOSYS;
2539
}
2540
2541
/**
2542
* hid_hw_output_report - send output report to device
2543
*
2544
* @hdev: hid device
2545
* @buf: raw data to transfer
2546
* @len: length of buf
2547
*
2548
* Return: count of data transferred, negative if error
2549
*/
2550
int hid_hw_output_report(struct hid_device *hdev, __u8 *buf, size_t len)
2551
{
2552
return __hid_hw_output_report(hdev, buf, len, 0, false);
2553
}
2554
EXPORT_SYMBOL_GPL(hid_hw_output_report);
2555
2556
#ifdef CONFIG_PM
2557
int hid_driver_suspend(struct hid_device *hdev, pm_message_t state)
2558
{
2559
if (hdev->driver && hdev->driver->suspend)
2560
return hdev->driver->suspend(hdev, state);
2561
2562
return 0;
2563
}
2564
EXPORT_SYMBOL_GPL(hid_driver_suspend);
2565
2566
int hid_driver_reset_resume(struct hid_device *hdev)
2567
{
2568
if (hdev->driver && hdev->driver->reset_resume)
2569
return hdev->driver->reset_resume(hdev);
2570
2571
return 0;
2572
}
2573
EXPORT_SYMBOL_GPL(hid_driver_reset_resume);
2574
2575
int hid_driver_resume(struct hid_device *hdev)
2576
{
2577
if (hdev->driver && hdev->driver->resume)
2578
return hdev->driver->resume(hdev);
2579
2580
return 0;
2581
}
2582
EXPORT_SYMBOL_GPL(hid_driver_resume);
2583
#endif /* CONFIG_PM */
2584
2585
struct hid_dynid {
2586
struct list_head list;
2587
struct hid_device_id id;
2588
};
2589
2590
/**
2591
* new_id_store - add a new HID device ID to this driver and re-probe devices
2592
* @drv: target device driver
2593
* @buf: buffer for scanning device ID data
2594
* @count: input size
2595
*
2596
* Adds a new dynamic hid device ID to this driver,
2597
* and causes the driver to probe for all devices again.
2598
*/
2599
static ssize_t new_id_store(struct device_driver *drv, const char *buf,
2600
size_t count)
2601
{
2602
struct hid_driver *hdrv = to_hid_driver(drv);
2603
struct hid_dynid *dynid;
2604
__u32 bus, vendor, product;
2605
unsigned long driver_data = 0;
2606
int ret;
2607
2608
ret = sscanf(buf, "%x %x %x %lx",
2609
&bus, &vendor, &product, &driver_data);
2610
if (ret < 3)
2611
return -EINVAL;
2612
2613
dynid = kzalloc(sizeof(*dynid), GFP_KERNEL);
2614
if (!dynid)
2615
return -ENOMEM;
2616
2617
dynid->id.bus = bus;
2618
dynid->id.group = HID_GROUP_ANY;
2619
dynid->id.vendor = vendor;
2620
dynid->id.product = product;
2621
dynid->id.driver_data = driver_data;
2622
2623
spin_lock(&hdrv->dyn_lock);
2624
list_add_tail(&dynid->list, &hdrv->dyn_list);
2625
spin_unlock(&hdrv->dyn_lock);
2626
2627
ret = driver_attach(&hdrv->driver);
2628
2629
return ret ? : count;
2630
}
2631
static DRIVER_ATTR_WO(new_id);
2632
2633
static struct attribute *hid_drv_attrs[] = {
2634
&driver_attr_new_id.attr,
2635
NULL,
2636
};
2637
ATTRIBUTE_GROUPS(hid_drv);
2638
2639
static void hid_free_dynids(struct hid_driver *hdrv)
2640
{
2641
struct hid_dynid *dynid, *n;
2642
2643
spin_lock(&hdrv->dyn_lock);
2644
list_for_each_entry_safe(dynid, n, &hdrv->dyn_list, list) {
2645
list_del(&dynid->list);
2646
kfree(dynid);
2647
}
2648
spin_unlock(&hdrv->dyn_lock);
2649
}
2650
2651
const struct hid_device_id *hid_match_device(struct hid_device *hdev,
2652
struct hid_driver *hdrv)
2653
{
2654
struct hid_dynid *dynid;
2655
2656
spin_lock(&hdrv->dyn_lock);
2657
list_for_each_entry(dynid, &hdrv->dyn_list, list) {
2658
if (hid_match_one_id(hdev, &dynid->id)) {
2659
spin_unlock(&hdrv->dyn_lock);
2660
return &dynid->id;
2661
}
2662
}
2663
spin_unlock(&hdrv->dyn_lock);
2664
2665
return hid_match_id(hdev, hdrv->id_table);
2666
}
2667
EXPORT_SYMBOL_GPL(hid_match_device);
2668
2669
static int hid_bus_match(struct device *dev, const struct device_driver *drv)
2670
{
2671
struct hid_driver *hdrv = to_hid_driver(drv);
2672
struct hid_device *hdev = to_hid_device(dev);
2673
2674
return hid_match_device(hdev, hdrv) != NULL;
2675
}
2676
2677
/**
2678
* hid_compare_device_paths - check if both devices share the same path
2679
* @hdev_a: hid device
2680
* @hdev_b: hid device
2681
* @separator: char to use as separator
2682
*
2683
* Check if two devices share the same path up to the last occurrence of
2684
* the separator char. Both paths must exist (i.e., zero-length paths
2685
* don't match).
2686
*/
2687
bool hid_compare_device_paths(struct hid_device *hdev_a,
2688
struct hid_device *hdev_b, char separator)
2689
{
2690
int n1 = strrchr(hdev_a->phys, separator) - hdev_a->phys;
2691
int n2 = strrchr(hdev_b->phys, separator) - hdev_b->phys;
2692
2693
if (n1 != n2 || n1 <= 0 || n2 <= 0)
2694
return false;
2695
2696
return !strncmp(hdev_a->phys, hdev_b->phys, n1);
2697
}
2698
EXPORT_SYMBOL_GPL(hid_compare_device_paths);
2699
2700
static bool hid_check_device_match(struct hid_device *hdev,
2701
struct hid_driver *hdrv,
2702
const struct hid_device_id **id)
2703
{
2704
*id = hid_match_device(hdev, hdrv);
2705
if (!*id)
2706
return false;
2707
2708
if (hdrv->match)
2709
return hdrv->match(hdev, hid_ignore_special_drivers);
2710
2711
/*
2712
* hid-generic implements .match(), so we must be dealing with a
2713
* different HID driver here, and can simply check if
2714
* hid_ignore_special_drivers or HID_QUIRK_IGNORE_SPECIAL_DRIVER
2715
* are set or not.
2716
*/
2717
return !hid_ignore_special_drivers && !(hdev->quirks & HID_QUIRK_IGNORE_SPECIAL_DRIVER);
2718
}
2719
2720
static void hid_set_group(struct hid_device *hdev)
2721
{
2722
int ret;
2723
2724
if (hid_ignore_special_drivers) {
2725
hdev->group = HID_GROUP_GENERIC;
2726
} else if (!hdev->group &&
2727
!(hdev->quirks & HID_QUIRK_HAVE_SPECIAL_DRIVER)) {
2728
ret = hid_scan_report(hdev);
2729
if (ret)
2730
hid_warn(hdev, "bad device descriptor (%d)\n", ret);
2731
}
2732
}
2733
2734
static int __hid_device_probe(struct hid_device *hdev, struct hid_driver *hdrv)
2735
{
2736
const struct hid_device_id *id;
2737
int ret;
2738
2739
if (!hdev->bpf_rsize) {
2740
/* we keep a reference to the currently scanned report descriptor */
2741
const __u8 *original_rdesc = hdev->bpf_rdesc;
2742
2743
if (!original_rdesc)
2744
original_rdesc = hdev->dev_rdesc;
2745
2746
/* in case a bpf program gets detached, we need to free the old one */
2747
hid_free_bpf_rdesc(hdev);
2748
2749
/* keep this around so we know we called it once */
2750
hdev->bpf_rsize = hdev->dev_rsize;
2751
2752
/* call_hid_bpf_rdesc_fixup will always return a valid pointer */
2753
hdev->bpf_rdesc = call_hid_bpf_rdesc_fixup(hdev, hdev->dev_rdesc,
2754
&hdev->bpf_rsize);
2755
2756
/* the report descriptor changed, we need to re-scan it */
2757
if (original_rdesc != hdev->bpf_rdesc) {
2758
hdev->group = 0;
2759
hid_set_group(hdev);
2760
}
2761
}
2762
2763
if (!hid_check_device_match(hdev, hdrv, &id))
2764
return -ENODEV;
2765
2766
hdev->devres_group_id = devres_open_group(&hdev->dev, NULL, GFP_KERNEL);
2767
if (!hdev->devres_group_id)
2768
return -ENOMEM;
2769
2770
/* reset the quirks that has been previously set */
2771
hdev->quirks = hid_lookup_quirk(hdev);
2772
hdev->driver = hdrv;
2773
2774
if (hdrv->probe) {
2775
ret = hdrv->probe(hdev, id);
2776
} else { /* default probe */
2777
ret = hid_open_report(hdev);
2778
if (!ret)
2779
ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
2780
}
2781
2782
/*
2783
* Note that we are not closing the devres group opened above so
2784
* even resources that were attached to the device after probe is
2785
* run are released when hid_device_remove() is executed. This is
2786
* needed as some drivers would allocate additional resources,
2787
* for example when updating firmware.
2788
*/
2789
2790
if (ret) {
2791
devres_release_group(&hdev->dev, hdev->devres_group_id);
2792
hid_close_report(hdev);
2793
hdev->driver = NULL;
2794
}
2795
2796
return ret;
2797
}
2798
2799
static int hid_device_probe(struct device *dev)
2800
{
2801
struct hid_device *hdev = to_hid_device(dev);
2802
struct hid_driver *hdrv = to_hid_driver(dev->driver);
2803
int ret = 0;
2804
2805
if (down_interruptible(&hdev->driver_input_lock))
2806
return -EINTR;
2807
2808
hdev->io_started = false;
2809
clear_bit(ffs(HID_STAT_REPROBED), &hdev->status);
2810
2811
if (!hdev->driver)
2812
ret = __hid_device_probe(hdev, hdrv);
2813
2814
if (!hdev->io_started)
2815
up(&hdev->driver_input_lock);
2816
2817
return ret;
2818
}
2819
2820
static void hid_device_remove(struct device *dev)
2821
{
2822
struct hid_device *hdev = to_hid_device(dev);
2823
struct hid_driver *hdrv;
2824
2825
down(&hdev->driver_input_lock);
2826
hdev->io_started = false;
2827
2828
hdrv = hdev->driver;
2829
if (hdrv) {
2830
if (hdrv->remove)
2831
hdrv->remove(hdev);
2832
else /* default remove */
2833
hid_hw_stop(hdev);
2834
2835
/* Release all devres resources allocated by the driver */
2836
devres_release_group(&hdev->dev, hdev->devres_group_id);
2837
2838
hid_close_report(hdev);
2839
hdev->driver = NULL;
2840
}
2841
2842
if (!hdev->io_started)
2843
up(&hdev->driver_input_lock);
2844
}
2845
2846
static ssize_t modalias_show(struct device *dev, struct device_attribute *a,
2847
char *buf)
2848
{
2849
struct hid_device *hdev = container_of(dev, struct hid_device, dev);
2850
2851
return sysfs_emit(buf, "hid:b%04Xg%04Xv%08Xp%08X\n",
2852
hdev->bus, hdev->group, hdev->vendor, hdev->product);
2853
}
2854
static DEVICE_ATTR_RO(modalias);
2855
2856
static struct attribute *hid_dev_attrs[] = {
2857
&dev_attr_modalias.attr,
2858
NULL,
2859
};
2860
static const struct bin_attribute *hid_dev_bin_attrs[] = {
2861
&bin_attr_report_descriptor,
2862
NULL
2863
};
2864
static const struct attribute_group hid_dev_group = {
2865
.attrs = hid_dev_attrs,
2866
.bin_attrs = hid_dev_bin_attrs,
2867
};
2868
__ATTRIBUTE_GROUPS(hid_dev);
2869
2870
static int hid_uevent(const struct device *dev, struct kobj_uevent_env *env)
2871
{
2872
const struct hid_device *hdev = to_hid_device(dev);
2873
2874
if (add_uevent_var(env, "HID_ID=%04X:%08X:%08X",
2875
hdev->bus, hdev->vendor, hdev->product))
2876
return -ENOMEM;
2877
2878
if (add_uevent_var(env, "HID_NAME=%s", hdev->name))
2879
return -ENOMEM;
2880
2881
if (add_uevent_var(env, "HID_PHYS=%s", hdev->phys))
2882
return -ENOMEM;
2883
2884
if (add_uevent_var(env, "HID_UNIQ=%s", hdev->uniq))
2885
return -ENOMEM;
2886
2887
if (add_uevent_var(env, "MODALIAS=hid:b%04Xg%04Xv%08Xp%08X",
2888
hdev->bus, hdev->group, hdev->vendor, hdev->product))
2889
return -ENOMEM;
2890
2891
return 0;
2892
}
2893
2894
const struct bus_type hid_bus_type = {
2895
.name = "hid",
2896
.dev_groups = hid_dev_groups,
2897
.drv_groups = hid_drv_groups,
2898
.match = hid_bus_match,
2899
.probe = hid_device_probe,
2900
.remove = hid_device_remove,
2901
.uevent = hid_uevent,
2902
};
2903
EXPORT_SYMBOL(hid_bus_type);
2904
2905
int hid_add_device(struct hid_device *hdev)
2906
{
2907
static atomic_t id = ATOMIC_INIT(0);
2908
int ret;
2909
2910
if (WARN_ON(hdev->status & HID_STAT_ADDED))
2911
return -EBUSY;
2912
2913
hdev->quirks = hid_lookup_quirk(hdev);
2914
2915
/* we need to kill them here, otherwise they will stay allocated to
2916
* wait for coming driver */
2917
if (hid_ignore(hdev))
2918
return -ENODEV;
2919
2920
/*
2921
* Check for the mandatory transport channel.
2922
*/
2923
if (!hdev->ll_driver->raw_request) {
2924
hid_err(hdev, "transport driver missing .raw_request()\n");
2925
return -EINVAL;
2926
}
2927
2928
/*
2929
* Read the device report descriptor once and use as template
2930
* for the driver-specific modifications.
2931
*/
2932
ret = hdev->ll_driver->parse(hdev);
2933
if (ret)
2934
return ret;
2935
if (!hdev->dev_rdesc)
2936
return -ENODEV;
2937
2938
/*
2939
* Scan generic devices for group information
2940
*/
2941
hid_set_group(hdev);
2942
2943
hdev->id = atomic_inc_return(&id);
2944
2945
/* XXX hack, any other cleaner solution after the driver core
2946
* is converted to allow more than 20 bytes as the device name? */
2947
dev_set_name(&hdev->dev, "%04X:%04X:%04X.%04X", hdev->bus,
2948
hdev->vendor, hdev->product, hdev->id);
2949
2950
hid_debug_register(hdev, dev_name(&hdev->dev));
2951
ret = device_add(&hdev->dev);
2952
if (!ret)
2953
hdev->status |= HID_STAT_ADDED;
2954
else
2955
hid_debug_unregister(hdev);
2956
2957
return ret;
2958
}
2959
EXPORT_SYMBOL_GPL(hid_add_device);
2960
2961
/**
2962
* hid_allocate_device - allocate new hid device descriptor
2963
*
2964
* Allocate and initialize hid device, so that hid_destroy_device might be
2965
* used to free it.
2966
*
2967
* New hid_device pointer is returned on success, otherwise ERR_PTR encoded
2968
* error value.
2969
*/
2970
struct hid_device *hid_allocate_device(void)
2971
{
2972
struct hid_device *hdev;
2973
int ret = -ENOMEM;
2974
2975
hdev = kzalloc(sizeof(*hdev), GFP_KERNEL);
2976
if (hdev == NULL)
2977
return ERR_PTR(ret);
2978
2979
device_initialize(&hdev->dev);
2980
hdev->dev.release = hid_device_release;
2981
hdev->dev.bus = &hid_bus_type;
2982
device_enable_async_suspend(&hdev->dev);
2983
2984
hid_close_report(hdev);
2985
2986
init_waitqueue_head(&hdev->debug_wait);
2987
INIT_LIST_HEAD(&hdev->debug_list);
2988
spin_lock_init(&hdev->debug_list_lock);
2989
sema_init(&hdev->driver_input_lock, 1);
2990
mutex_init(&hdev->ll_open_lock);
2991
kref_init(&hdev->ref);
2992
2993
ret = hid_bpf_device_init(hdev);
2994
if (ret)
2995
goto out_err;
2996
2997
return hdev;
2998
2999
out_err:
3000
hid_destroy_device(hdev);
3001
return ERR_PTR(ret);
3002
}
3003
EXPORT_SYMBOL_GPL(hid_allocate_device);
3004
3005
static void hid_remove_device(struct hid_device *hdev)
3006
{
3007
if (hdev->status & HID_STAT_ADDED) {
3008
device_del(&hdev->dev);
3009
hid_debug_unregister(hdev);
3010
hdev->status &= ~HID_STAT_ADDED;
3011
}
3012
hid_free_bpf_rdesc(hdev);
3013
kfree(hdev->dev_rdesc);
3014
hdev->dev_rdesc = NULL;
3015
hdev->dev_rsize = 0;
3016
hdev->bpf_rsize = 0;
3017
}
3018
3019
/**
3020
* hid_destroy_device - free previously allocated device
3021
*
3022
* @hdev: hid device
3023
*
3024
* If you allocate hid_device through hid_allocate_device, you should ever
3025
* free by this function.
3026
*/
3027
void hid_destroy_device(struct hid_device *hdev)
3028
{
3029
hid_bpf_destroy_device(hdev);
3030
hid_remove_device(hdev);
3031
put_device(&hdev->dev);
3032
}
3033
EXPORT_SYMBOL_GPL(hid_destroy_device);
3034
3035
3036
static int __hid_bus_reprobe_drivers(struct device *dev, void *data)
3037
{
3038
struct hid_driver *hdrv = data;
3039
struct hid_device *hdev = to_hid_device(dev);
3040
3041
if (hdev->driver == hdrv &&
3042
!hdrv->match(hdev, hid_ignore_special_drivers) &&
3043
!test_and_set_bit(ffs(HID_STAT_REPROBED), &hdev->status))
3044
return device_reprobe(dev);
3045
3046
return 0;
3047
}
3048
3049
static int __hid_bus_driver_added(struct device_driver *drv, void *data)
3050
{
3051
struct hid_driver *hdrv = to_hid_driver(drv);
3052
3053
if (hdrv->match) {
3054
bus_for_each_dev(&hid_bus_type, NULL, hdrv,
3055
__hid_bus_reprobe_drivers);
3056
}
3057
3058
return 0;
3059
}
3060
3061
static int __bus_removed_driver(struct device_driver *drv, void *data)
3062
{
3063
return bus_rescan_devices(&hid_bus_type);
3064
}
3065
3066
int __hid_register_driver(struct hid_driver *hdrv, struct module *owner,
3067
const char *mod_name)
3068
{
3069
int ret;
3070
3071
hdrv->driver.name = hdrv->name;
3072
hdrv->driver.bus = &hid_bus_type;
3073
hdrv->driver.owner = owner;
3074
hdrv->driver.mod_name = mod_name;
3075
3076
INIT_LIST_HEAD(&hdrv->dyn_list);
3077
spin_lock_init(&hdrv->dyn_lock);
3078
3079
ret = driver_register(&hdrv->driver);
3080
3081
if (ret == 0)
3082
bus_for_each_drv(&hid_bus_type, NULL, NULL,
3083
__hid_bus_driver_added);
3084
3085
return ret;
3086
}
3087
EXPORT_SYMBOL_GPL(__hid_register_driver);
3088
3089
void hid_unregister_driver(struct hid_driver *hdrv)
3090
{
3091
driver_unregister(&hdrv->driver);
3092
hid_free_dynids(hdrv);
3093
3094
bus_for_each_drv(&hid_bus_type, NULL, hdrv, __bus_removed_driver);
3095
}
3096
EXPORT_SYMBOL_GPL(hid_unregister_driver);
3097
3098
int hid_check_keys_pressed(struct hid_device *hid)
3099
{
3100
struct hid_input *hidinput;
3101
int i;
3102
3103
if (!(hid->claimed & HID_CLAIMED_INPUT))
3104
return 0;
3105
3106
list_for_each_entry(hidinput, &hid->inputs, list) {
3107
for (i = 0; i < BITS_TO_LONGS(KEY_MAX); i++)
3108
if (hidinput->input->key[i])
3109
return 1;
3110
}
3111
3112
return 0;
3113
}
3114
EXPORT_SYMBOL_GPL(hid_check_keys_pressed);
3115
3116
#ifdef CONFIG_HID_BPF
3117
static const struct hid_ops __hid_ops = {
3118
.hid_get_report = hid_get_report,
3119
.hid_hw_raw_request = __hid_hw_raw_request,
3120
.hid_hw_output_report = __hid_hw_output_report,
3121
.hid_input_report = __hid_input_report,
3122
.owner = THIS_MODULE,
3123
.bus_type = &hid_bus_type,
3124
};
3125
#endif
3126
3127
static int __init hid_init(void)
3128
{
3129
int ret;
3130
3131
ret = bus_register(&hid_bus_type);
3132
if (ret) {
3133
pr_err("can't register hid bus\n");
3134
goto err;
3135
}
3136
3137
#ifdef CONFIG_HID_BPF
3138
hid_ops = &__hid_ops;
3139
#endif
3140
3141
ret = hidraw_init();
3142
if (ret)
3143
goto err_bus;
3144
3145
hid_debug_init();
3146
3147
return 0;
3148
err_bus:
3149
bus_unregister(&hid_bus_type);
3150
err:
3151
return ret;
3152
}
3153
3154
static void __exit hid_exit(void)
3155
{
3156
#ifdef CONFIG_HID_BPF
3157
hid_ops = NULL;
3158
#endif
3159
hid_debug_exit();
3160
hidraw_exit();
3161
bus_unregister(&hid_bus_type);
3162
hid_quirks_exit(HID_BUS_ANY);
3163
}
3164
3165
module_init(hid_init);
3166
module_exit(hid_exit);
3167
3168
MODULE_AUTHOR("Andreas Gal");
3169
MODULE_AUTHOR("Vojtech Pavlik");
3170
MODULE_AUTHOR("Jiri Kosina");
3171
MODULE_DESCRIPTION("HID support for Linux");
3172
MODULE_LICENSE("GPL");
3173
3174