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treewide: remove redundant IS_ERR() before error code check
[linux/fpc-iii.git] / drivers / hid / hid-core.c
blob851fe54ea59e7c2636ab204372c49b749a136014
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 <vojtech@suse.cz>
7 * Copyright (c) 2005 Michael Haboustak <mike-@cinci.rr.com> for Concept2, Inc
8 * 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>
21 #include <linux/mm.h>
22 #include <linux/spinlock.h>
23 #include <asm/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 int hid_debug = 0;
45 module_param_named(debug, hid_debug, int, 0600);
46 MODULE_PARM_DESC(debug, "toggle HID debugging messages");
47 EXPORT_SYMBOL_GPL(hid_debug);
48
49 static int hid_ignore_special_drivers = 0;
50 module_param_named(ignore_special_drivers, hid_ignore_special_drivers, int, 0600);
51 MODULE_PARM_DESC(ignore_special_drivers, "Ignore any special drivers and handle all devices by generic driver");
52
53 /*
54 * Register a new report for a device.
55 */
56
57 struct hid_report *hid_register_report(struct hid_device *device,
58 unsigned int type, unsigned int id,
59 unsigned int application)
60 {
61 struct hid_report_enum *report_enum = device->report_enum + type;
62 struct hid_report *report;
63
64 if (id >= HID_MAX_IDS)
65 return NULL;
66 if (report_enum->report_id_hash[id])
67 return report_enum->report_id_hash[id];
68
69 report = kzalloc(sizeof(struct hid_report), GFP_KERNEL);
70 if (!report)
71 return NULL;
72
73 if (id != 0)
74 report_enum->numbered = 1;
75
76 report->id = id;
77 report->type = type;
78 report->size = 0;
79 report->device = device;
80 report->application = application;
81 report_enum->report_id_hash[id] = report;
82
83 list_add_tail(&report->list, &report_enum->report_list);
84
85 return report;
86 }
87 EXPORT_SYMBOL_GPL(hid_register_report);
88
89 /*
90 * Register a new field for this report.
91 */
92
93 static struct hid_field *hid_register_field(struct hid_report *report, unsigned usages, unsigned values)
94 {
95 struct hid_field *field;
96
97 if (report->maxfield == HID_MAX_FIELDS) {
98 hid_err(report->device, "too many fields in report\n");
99 return NULL;
100 }
101
102 field = kzalloc((sizeof(struct hid_field) +
103 usages * sizeof(struct hid_usage) +
104 values * sizeof(unsigned)), GFP_KERNEL);
105 if (!field)
106 return NULL;
107
108 field->index = report->maxfield++;
109 report->field[field->index] = field;
110 field->usage = (struct hid_usage *)(field + 1);
111 field->value = (s32 *)(field->usage + usages);
112 field->report = report;
113
114 return field;
115 }
116
117 /*
118 * Open a collection. The type/usage is pushed on the stack.
119 */
120
121 static int open_collection(struct hid_parser *parser, unsigned type)
122 {
123 struct hid_collection *collection;
124 unsigned usage;
125 int collection_index;
126
127 usage = parser->local.usage[0];
128
129 if (parser->collection_stack_ptr == parser->collection_stack_size) {
130 unsigned int *collection_stack;
131 unsigned int new_size = parser->collection_stack_size +
132 HID_COLLECTION_STACK_SIZE;
133
134 collection_stack = krealloc(parser->collection_stack,
135 new_size * sizeof(unsigned int),
136 GFP_KERNEL);
137 if (!collection_stack)
138 return -ENOMEM;
139
140 parser->collection_stack = collection_stack;
141 parser->collection_stack_size = new_size;
142 }
143
144 if (parser->device->maxcollection == parser->device->collection_size) {
145 collection = kmalloc(
146 array3_size(sizeof(struct hid_collection),
147 parser->device->collection_size,
148 2),
149 GFP_KERNEL);
150 if (collection == NULL) {
151 hid_err(parser->device, "failed to reallocate collection array\n");
152 return -ENOMEM;
153 }
154 memcpy(collection, parser->device->collection,
155 sizeof(struct hid_collection) *
156 parser->device->collection_size);
157 memset(collection + parser->device->collection_size, 0,
158 sizeof(struct hid_collection) *
159 parser->device->collection_size);
160 kfree(parser->device->collection);
161 parser->device->collection = collection;
162 parser->device->collection_size *= 2;
163 }
164
165 parser->collection_stack[parser->collection_stack_ptr++] =
166 parser->device->maxcollection;
167
168 collection_index = parser->device->maxcollection++;
169 collection = parser->device->collection + collection_index;
170 collection->type = type;
171 collection->usage = usage;
172 collection->level = parser->collection_stack_ptr - 1;
173 collection->parent_idx = (collection->level == 0) ? -1 :
174 parser->collection_stack[collection->level - 1];
175
176 if (type == HID_COLLECTION_APPLICATION)
177 parser->device->maxapplication++;
178
179 return 0;
180 }
181
182 /*
183 * Close a collection.
184 */
185
186 static int close_collection(struct hid_parser *parser)
187 {
188 if (!parser->collection_stack_ptr) {
189 hid_err(parser->device, "collection stack underflow\n");
190 return -EINVAL;
191 }
192 parser->collection_stack_ptr--;
193 return 0;
194 }
195
196 /*
197 * Climb up the stack, search for the specified collection type
198 * and return the usage.
199 */
200
201 static unsigned hid_lookup_collection(struct hid_parser *parser, unsigned type)
202 {
203 struct hid_collection *collection = parser->device->collection;
204 int n;
205
206 for (n = parser->collection_stack_ptr - 1; n >= 0; n--) {
207 unsigned index = parser->collection_stack[n];
208 if (collection[index].type == type)
209 return collection[index].usage;
210 }
211 return 0; /* we know nothing about this usage type */
212 }
213
214 /*
215 * Concatenate usage which defines 16 bits or less with the
216 * currently defined usage page to form a 32 bit usage
217 */
218
219 static void complete_usage(struct hid_parser *parser, unsigned int index)
220 {
221 parser->local.usage[index] &= 0xFFFF;
222 parser->local.usage[index] |=
223 (parser->global.usage_page & 0xFFFF) << 16;
224 }
225
226 /*
227 * Add a usage to the temporary parser table.
228 */
229
230 static int hid_add_usage(struct hid_parser *parser, unsigned usage, u8 size)
231 {
232 if (parser->local.usage_index >= HID_MAX_USAGES) {
233 hid_err(parser->device, "usage index exceeded\n");
234 return -1;
235 }
236 parser->local.usage[parser->local.usage_index] = usage;
237
238 /*
239 * If Usage item only includes usage id, concatenate it with
240 * currently defined usage page
241 */
242 if (size <= 2)
243 complete_usage(parser, parser->local.usage_index);
244
245 parser->local.usage_size[parser->local.usage_index] = size;
246 parser->local.collection_index[parser->local.usage_index] =
247 parser->collection_stack_ptr ?
248 parser->collection_stack[parser->collection_stack_ptr - 1] : 0;
249 parser->local.usage_index++;
250 return 0;
251 }
252
253 /*
254 * Register a new field for this report.
255 */
256
257 static int hid_add_field(struct hid_parser *parser, unsigned report_type, unsigned flags)
258 {
259 struct hid_report *report;
260 struct hid_field *field;
261 unsigned int usages;
262 unsigned int offset;
263 unsigned int i;
264 unsigned int application;
265
266 application = hid_lookup_collection(parser, HID_COLLECTION_APPLICATION);
267
268 report = hid_register_report(parser->device, report_type,
269 parser->global.report_id, application);
270 if (!report) {
271 hid_err(parser->device, "hid_register_report failed\n");
272 return -1;
273 }
274
275 /* Handle both signed and unsigned cases properly */
276 if ((parser->global.logical_minimum < 0 &&
277 parser->global.logical_maximum <
278 parser->global.logical_minimum) ||
279 (parser->global.logical_minimum >= 0 &&
280 (__u32)parser->global.logical_maximum <
281 (__u32)parser->global.logical_minimum)) {
282 dbg_hid("logical range invalid 0x%x 0x%x\n",
283 parser->global.logical_minimum,
284 parser->global.logical_maximum);
285 return -1;
286 }
287
288 offset = report->size;
289 report->size += parser->global.report_size * parser->global.report_count;
290
291 /* Total size check: Allow for possible report index byte */
292 if (report->size > (HID_MAX_BUFFER_SIZE - 1) << 3) {
293 hid_err(parser->device, "report is too long\n");
294 return -1;
295 }
296
297 if (!parser->local.usage_index) /* Ignore padding fields */
298 return 0;
299
300 usages = max_t(unsigned, parser->local.usage_index,
301 parser->global.report_count);
302
303 field = hid_register_field(report, usages, parser->global.report_count);
304 if (!field)
305 return 0;
306
307 field->physical = hid_lookup_collection(parser, HID_COLLECTION_PHYSICAL);
308 field->logical = hid_lookup_collection(parser, HID_COLLECTION_LOGICAL);
309 field->application = application;
310
311 for (i = 0; i < usages; i++) {
312 unsigned j = i;
313 /* Duplicate the last usage we parsed if we have excess values */
314 if (i >= parser->local.usage_index)
315 j = parser->local.usage_index - 1;
316 field->usage[i].hid = parser->local.usage[j];
317 field->usage[i].collection_index =
318 parser->local.collection_index[j];
319 field->usage[i].usage_index = i;
320 field->usage[i].resolution_multiplier = 1;
321 }
322
323 field->maxusage = usages;
324 field->flags = flags;
325 field->report_offset = offset;
326 field->report_type = report_type;
327 field->report_size = parser->global.report_size;
328 field->report_count = parser->global.report_count;
329 field->logical_minimum = parser->global.logical_minimum;
330 field->logical_maximum = parser->global.logical_maximum;
331 field->physical_minimum = parser->global.physical_minimum;
332 field->physical_maximum = parser->global.physical_maximum;
333 field->unit_exponent = parser->global.unit_exponent;
334 field->unit = parser->global.unit;
335
336 return 0;
337 }
338
339 /*
340 * Read data value from item.
341 */
342
343 static u32 item_udata(struct hid_item *item)
344 {
345 switch (item->size) {
346 case 1: return item->data.u8;
347 case 2: return item->data.u16;
348 case 4: return item->data.u32;
349 }
350 return 0;
351 }
352
353 static s32 item_sdata(struct hid_item *item)
354 {
355 switch (item->size) {
356 case 1: return item->data.s8;
357 case 2: return item->data.s16;
358 case 4: return item->data.s32;
359 }
360 return 0;
361 }
362
363 /*
364 * Process a global item.
365 */
366
367 static int hid_parser_global(struct hid_parser *parser, struct hid_item *item)
368 {
369 __s32 raw_value;
370 switch (item->tag) {
371 case HID_GLOBAL_ITEM_TAG_PUSH:
372
373 if (parser->global_stack_ptr == HID_GLOBAL_STACK_SIZE) {
374 hid_err(parser->device, "global environment stack overflow\n");
375 return -1;
376 }
377
378 memcpy(parser->global_stack + parser->global_stack_ptr++,
379 &parser->global, sizeof(struct hid_global));
380 return 0;
381
382 case HID_GLOBAL_ITEM_TAG_POP:
383
384 if (!parser->global_stack_ptr) {
385 hid_err(parser->device, "global environment stack underflow\n");
386 return -1;
387 }
388
389 memcpy(&parser->global, parser->global_stack +
390 --parser->global_stack_ptr, sizeof(struct hid_global));
391 return 0;
392
393 case HID_GLOBAL_ITEM_TAG_USAGE_PAGE:
394 parser->global.usage_page = item_udata(item);
395 return 0;
396
397 case HID_GLOBAL_ITEM_TAG_LOGICAL_MINIMUM:
398 parser->global.logical_minimum = item_sdata(item);
399 return 0;
400
401 case HID_GLOBAL_ITEM_TAG_LOGICAL_MAXIMUM:
402 if (parser->global.logical_minimum < 0)
403 parser->global.logical_maximum = item_sdata(item);
404 else
405 parser->global.logical_maximum = item_udata(item);
406 return 0;
407
408 case HID_GLOBAL_ITEM_TAG_PHYSICAL_MINIMUM:
409 parser->global.physical_minimum = item_sdata(item);
410 return 0;
411
412 case HID_GLOBAL_ITEM_TAG_PHYSICAL_MAXIMUM:
413 if (parser->global.physical_minimum < 0)
414 parser->global.physical_maximum = item_sdata(item);
415 else
416 parser->global.physical_maximum = item_udata(item);
417 return 0;
418
419 case HID_GLOBAL_ITEM_TAG_UNIT_EXPONENT:
420 /* Many devices provide unit exponent as a two's complement
421 * nibble due to the common misunderstanding of HID
422 * specification 1.11, 6.2.2.7 Global Items. Attempt to handle
423 * both this and the standard encoding. */
424 raw_value = item_sdata(item);
425 if (!(raw_value & 0xfffffff0))
426 parser->global.unit_exponent = hid_snto32(raw_value, 4);
427 else
428 parser->global.unit_exponent = raw_value;
429 return 0;
430
431 case HID_GLOBAL_ITEM_TAG_UNIT:
432 parser->global.unit = item_udata(item);
433 return 0;
434
435 case HID_GLOBAL_ITEM_TAG_REPORT_SIZE:
436 parser->global.report_size = item_udata(item);
437 if (parser->global.report_size > 256) {
438 hid_err(parser->device, "invalid report_size %d\n",
439 parser->global.report_size);
440 return -1;
441 }
442 return 0;
443
444 case HID_GLOBAL_ITEM_TAG_REPORT_COUNT:
445 parser->global.report_count = item_udata(item);
446 if (parser->global.report_count > HID_MAX_USAGES) {
447 hid_err(parser->device, "invalid report_count %d\n",
448 parser->global.report_count);
449 return -1;
450 }
451 return 0;
452
453 case HID_GLOBAL_ITEM_TAG_REPORT_ID:
454 parser->global.report_id = item_udata(item);
455 if (parser->global.report_id == 0 ||
456 parser->global.report_id >= HID_MAX_IDS) {
457 hid_err(parser->device, "report_id %u is invalid\n",
458 parser->global.report_id);
459 return -1;
460 }
461 return 0;
462
463 default:
464 hid_err(parser->device, "unknown global tag 0x%x\n", item->tag);
465 return -1;
466 }
467 }
468
469 /*
470 * Process a local item.
471 */
472
473 static int hid_parser_local(struct hid_parser *parser, struct hid_item *item)
474 {
475 __u32 data;
476 unsigned n;
477 __u32 count;
478
479 data = item_udata(item);
480
481 switch (item->tag) {
482 case HID_LOCAL_ITEM_TAG_DELIMITER:
483
484 if (data) {
485 /*
486 * We treat items before the first delimiter
487 * as global to all usage sets (branch 0).
488 * In the moment we process only these global
489 * items and the first delimiter set.
490 */
491 if (parser->local.delimiter_depth != 0) {
492 hid_err(parser->device, "nested delimiters\n");
493 return -1;
494 }
495 parser->local.delimiter_depth++;
496 parser->local.delimiter_branch++;
497 } else {
498 if (parser->local.delimiter_depth < 1) {
499 hid_err(parser->device, "bogus close delimiter\n");
500 return -1;
501 }
502 parser->local.delimiter_depth--;
503 }
504 return 0;
505
506 case HID_LOCAL_ITEM_TAG_USAGE:
507
508 if (parser->local.delimiter_branch > 1) {
509 dbg_hid("alternative usage ignored\n");
510 return 0;
511 }
512
513 return hid_add_usage(parser, data, item->size);
514
515 case HID_LOCAL_ITEM_TAG_USAGE_MINIMUM:
516
517 if (parser->local.delimiter_branch > 1) {
518 dbg_hid("alternative usage ignored\n");
519 return 0;
520 }
521
522 parser->local.usage_minimum = data;
523 return 0;
524
525 case HID_LOCAL_ITEM_TAG_USAGE_MAXIMUM:
526
527 if (parser->local.delimiter_branch > 1) {
528 dbg_hid("alternative usage ignored\n");
529 return 0;
530 }
531
532 count = data - parser->local.usage_minimum;
533 if (count + parser->local.usage_index >= HID_MAX_USAGES) {
534 /*
535 * We do not warn if the name is not set, we are
536 * actually pre-scanning the device.
537 */
538 if (dev_name(&parser->device->dev))
539 hid_warn(parser->device,
540 "ignoring exceeding usage max\n");
541 data = HID_MAX_USAGES - parser->local.usage_index +
542 parser->local.usage_minimum - 1;
543 if (data <= 0) {
544 hid_err(parser->device,
545 "no more usage index available\n");
546 return -1;
547 }
548 }
549
550 for (n = parser->local.usage_minimum; n <= data; n++)
551 if (hid_add_usage(parser, n, item->size)) {
552 dbg_hid("hid_add_usage failed\n");
553 return -1;
554 }
555 return 0;
556
557 default:
558
559 dbg_hid("unknown local item tag 0x%x\n", item->tag);
560 return 0;
561 }
562 return 0;
563 }
564
565 /*
566 * Concatenate Usage Pages into Usages where relevant:
567 * As per specification, 6.2.2.8: "When the parser encounters a main item it
568 * concatenates the last declared Usage Page with a Usage to form a complete
569 * usage value."
570 */
571
572 static void hid_concatenate_last_usage_page(struct hid_parser *parser)
573 {
574 int i;
575 unsigned int usage_page;
576 unsigned int current_page;
577
578 if (!parser->local.usage_index)
579 return;
580
581 usage_page = parser->global.usage_page;
582
583 /*
584 * Concatenate usage page again only if last declared Usage Page
585 * has not been already used in previous usages concatenation
586 */
587 for (i = parser->local.usage_index - 1; i >= 0; i--) {
588 if (parser->local.usage_size[i] > 2)
589 /* Ignore extended usages */
590 continue;
591
592 current_page = parser->local.usage[i] >> 16;
593 if (current_page == usage_page)
594 break;
595
596 complete_usage(parser, i);
597 }
598 }
599
600 /*
601 * Process a main item.
602 */
603
604 static int hid_parser_main(struct hid_parser *parser, struct hid_item *item)
605 {
606 __u32 data;
607 int ret;
608
609 hid_concatenate_last_usage_page(parser);
610
611 data = item_udata(item);
612
613 switch (item->tag) {
614 case HID_MAIN_ITEM_TAG_BEGIN_COLLECTION:
615 ret = open_collection(parser, data & 0xff);
616 break;
617 case HID_MAIN_ITEM_TAG_END_COLLECTION:
618 ret = close_collection(parser);
619 break;
620 case HID_MAIN_ITEM_TAG_INPUT:
621 ret = hid_add_field(parser, HID_INPUT_REPORT, data);
622 break;
623 case HID_MAIN_ITEM_TAG_OUTPUT:
624 ret = hid_add_field(parser, HID_OUTPUT_REPORT, data);
625 break;
626 case HID_MAIN_ITEM_TAG_FEATURE:
627 ret = hid_add_field(parser, HID_FEATURE_REPORT, data);
628 break;
629 default:
630 hid_warn(parser->device, "unknown main item tag 0x%x\n", item->tag);
631 ret = 0;
632 }
633
634 memset(&parser->local, 0, sizeof(parser->local)); /* Reset the local parser environment */
635
636 return ret;
637 }
638
639 /*
640 * Process a reserved item.
641 */
642
643 static int hid_parser_reserved(struct hid_parser *parser, struct hid_item *item)
644 {
645 dbg_hid("reserved item type, tag 0x%x\n", item->tag);
646 return 0;
647 }
648
649 /*
650 * Free a report and all registered fields. The field->usage and
651 * field->value table's are allocated behind the field, so we need
652 * only to free(field) itself.
653 */
654
655 static void hid_free_report(struct hid_report *report)
656 {
657 unsigned n;
658
659 for (n = 0; n < report->maxfield; n++)
660 kfree(report->field[n]);
661 kfree(report);
662 }
663
664 /*
665 * Close report. This function returns the device
666 * state to the point prior to hid_open_report().
667 */
668 static void hid_close_report(struct hid_device *device)
669 {
670 unsigned i, j;
671
672 for (i = 0; i < HID_REPORT_TYPES; i++) {
673 struct hid_report_enum *report_enum = device->report_enum + i;
674
675 for (j = 0; j < HID_MAX_IDS; j++) {
676 struct hid_report *report = report_enum->report_id_hash[j];
677 if (report)
678 hid_free_report(report);
679 }
680 memset(report_enum, 0, sizeof(*report_enum));
681 INIT_LIST_HEAD(&report_enum->report_list);
682 }
683
684 kfree(device->rdesc);
685 device->rdesc = NULL;
686 device->rsize = 0;
687
688 kfree(device->collection);
689 device->collection = NULL;
690 device->collection_size = 0;
691 device->maxcollection = 0;
692 device->maxapplication = 0;
693
694 device->status &= ~HID_STAT_PARSED;
695 }
696
697 /*
698 * Free a device structure, all reports, and all fields.
699 */
700
701 static void hid_device_release(struct device *dev)
702 {
703 struct hid_device *hid = to_hid_device(dev);
704
705 hid_close_report(hid);
706 kfree(hid->dev_rdesc);
707 kfree(hid);
708 }
709
710 /*
711 * Fetch a report description item from the data stream. We support long
712 * items, though they are not used yet.
713 */
714
715 static u8 *fetch_item(__u8 *start, __u8 *end, struct hid_item *item)
716 {
717 u8 b;
718
719 if ((end - start) <= 0)
720 return NULL;
721
722 b = *start++;
723
724 item->type = (b >> 2) & 3;
725 item->tag = (b >> 4) & 15;
726
727 if (item->tag == HID_ITEM_TAG_LONG) {
728
729 item->format = HID_ITEM_FORMAT_LONG;
730
731 if ((end - start) < 2)
732 return NULL;
733
734 item->size = *start++;
735 item->tag = *start++;
736
737 if ((end - start) < item->size)
738 return NULL;
739
740 item->data.longdata = start;
741 start += item->size;
742 return start;
743 }
744
745 item->format = HID_ITEM_FORMAT_SHORT;
746 item->size = b & 3;
747
748 switch (item->size) {
749 case 0:
750 return start;
751
752 case 1:
753 if ((end - start) < 1)
754 return NULL;
755 item->data.u8 = *start++;
756 return start;
757
758 case 2:
759 if ((end - start) < 2)
760 return NULL;
761 item->data.u16 = get_unaligned_le16(start);
762 start = (__u8 *)((__le16 *)start + 1);
763 return start;
764
765 case 3:
766 item->size++;
767 if ((end - start) < 4)
768 return NULL;
769 item->data.u32 = get_unaligned_le32(start);
770 start = (__u8 *)((__le32 *)start + 1);
771 return start;
772 }
773
774 return NULL;
775 }
776
777 static void hid_scan_input_usage(struct hid_parser *parser, u32 usage)
778 {
779 struct hid_device *hid = parser->device;
780
781 if (usage == HID_DG_CONTACTID)
782 hid->group = HID_GROUP_MULTITOUCH;
783 }
784
785 static void hid_scan_feature_usage(struct hid_parser *parser, u32 usage)
786 {
787 if (usage == 0xff0000c5 && parser->global.report_count == 256 &&
788 parser->global.report_size == 8)
789 parser->scan_flags |= HID_SCAN_FLAG_MT_WIN_8;
790
791 if (usage == 0xff0000c6 && parser->global.report_count == 1 &&
792 parser->global.report_size == 8)
793 parser->scan_flags |= HID_SCAN_FLAG_MT_WIN_8;
794 }
795
796 static void hid_scan_collection(struct hid_parser *parser, unsigned type)
797 {
798 struct hid_device *hid = parser->device;
799 int i;
800
801 if (((parser->global.usage_page << 16) == HID_UP_SENSOR) &&
802 type == HID_COLLECTION_PHYSICAL)
803 hid->group = HID_GROUP_SENSOR_HUB;
804
805 if (hid->vendor == USB_VENDOR_ID_MICROSOFT &&
806 hid->product == USB_DEVICE_ID_MS_POWER_COVER &&
807 hid->group == HID_GROUP_MULTITOUCH)
808 hid->group = HID_GROUP_GENERIC;
809
810 if ((parser->global.usage_page << 16) == HID_UP_GENDESK)
811 for (i = 0; i < parser->local.usage_index; i++)
812 if (parser->local.usage[i] == HID_GD_POINTER)
813 parser->scan_flags |= HID_SCAN_FLAG_GD_POINTER;
814
815 if ((parser->global.usage_page << 16) >= HID_UP_MSVENDOR)
816 parser->scan_flags |= HID_SCAN_FLAG_VENDOR_SPECIFIC;
817 }
818
819 static int hid_scan_main(struct hid_parser *parser, struct hid_item *item)
820 {
821 __u32 data;
822 int i;
823
824 hid_concatenate_last_usage_page(parser);
825
826 data = item_udata(item);
827
828 switch (item->tag) {
829 case HID_MAIN_ITEM_TAG_BEGIN_COLLECTION:
830 hid_scan_collection(parser, data & 0xff);
831 break;
832 case HID_MAIN_ITEM_TAG_END_COLLECTION:
833 break;
834 case HID_MAIN_ITEM_TAG_INPUT:
835 /* ignore constant inputs, they will be ignored by hid-input */
836 if (data & HID_MAIN_ITEM_CONSTANT)
837 break;
838 for (i = 0; i < parser->local.usage_index; i++)
839 hid_scan_input_usage(parser, parser->local.usage[i]);
840 break;
841 case HID_MAIN_ITEM_TAG_OUTPUT:
842 break;
843 case HID_MAIN_ITEM_TAG_FEATURE:
844 for (i = 0; i < parser->local.usage_index; i++)
845 hid_scan_feature_usage(parser, parser->local.usage[i]);
846 break;
847 }
848
849 /* Reset the local parser environment */
850 memset(&parser->local, 0, sizeof(parser->local));
851
852 return 0;
853 }
854
855 /*
856 * Scan a report descriptor before the device is added to the bus.
857 * Sets device groups and other properties that determine what driver
858 * to load.
859 */
860 static int hid_scan_report(struct hid_device *hid)
861 {
862 struct hid_parser *parser;
863 struct hid_item item;
864 __u8 *start = hid->dev_rdesc;
865 __u8 *end = start + hid->dev_rsize;
866 static int (*dispatch_type[])(struct hid_parser *parser,
867 struct hid_item *item) = {
868 hid_scan_main,
869 hid_parser_global,
870 hid_parser_local,
871 hid_parser_reserved
872 };
873
874 parser = vzalloc(sizeof(struct hid_parser));
875 if (!parser)
876 return -ENOMEM;
877
878 parser->device = hid;
879 hid->group = HID_GROUP_GENERIC;
880
881 /*
882 * The parsing is simpler than the one in hid_open_report() as we should
883 * be robust against hid errors. Those errors will be raised by
884 * hid_open_report() anyway.
885 */
886 while ((start = fetch_item(start, end, &item)) != NULL)
887 dispatch_type[item.type](parser, &item);
888
889 /*
890 * Handle special flags set during scanning.
891 */
892 if ((parser->scan_flags & HID_SCAN_FLAG_MT_WIN_8) &&
893 (hid->group == HID_GROUP_MULTITOUCH))
894 hid->group = HID_GROUP_MULTITOUCH_WIN_8;
895
896 /*
897 * Vendor specific handlings
898 */
899 switch (hid->vendor) {
900 case USB_VENDOR_ID_WACOM:
901 hid->group = HID_GROUP_WACOM;
902 break;
903 case USB_VENDOR_ID_SYNAPTICS:
904 if (hid->group == HID_GROUP_GENERIC)
905 if ((parser->scan_flags & HID_SCAN_FLAG_VENDOR_SPECIFIC)
906 && (parser->scan_flags & HID_SCAN_FLAG_GD_POINTER))
907 /*
908 * hid-rmi should take care of them,
909 * not hid-generic
910 */
911 hid->group = HID_GROUP_RMI;
912 break;
913 }
914
915 kfree(parser->collection_stack);
916 vfree(parser);
917 return 0;
918 }
919
920 /**
921 * hid_parse_report - parse device report
922 *
923 * @device: hid device
924 * @start: report start
925 * @size: report size
926 *
927 * Allocate the device report as read by the bus driver. This function should
928 * only be called from parse() in ll drivers.
929 */
930 int hid_parse_report(struct hid_device *hid, __u8 *start, unsigned size)
931 {
932 hid->dev_rdesc = kmemdup(start, size, GFP_KERNEL);
933 if (!hid->dev_rdesc)
934 return -ENOMEM;
935 hid->dev_rsize = size;
936 return 0;
937 }
938 EXPORT_SYMBOL_GPL(hid_parse_report);
939
940 static const char * const hid_report_names[] = {
941 "HID_INPUT_REPORT",
942 "HID_OUTPUT_REPORT",
943 "HID_FEATURE_REPORT",
944 };
945 /**
946 * hid_validate_values - validate existing device report's value indexes
947 *
948 * @device: hid device
949 * @type: which report type to examine
950 * @id: which report ID to examine (0 for first)
951 * @field_index: which report field to examine
952 * @report_counts: expected number of values
953 *
954 * Validate the number of values in a given field of a given report, after
955 * parsing.
956 */
957 struct hid_report *hid_validate_values(struct hid_device *hid,
958 unsigned int type, unsigned int id,
959 unsigned int field_index,
960 unsigned int report_counts)
961 {
962 struct hid_report *report;
963
964 if (type > HID_FEATURE_REPORT) {
965 hid_err(hid, "invalid HID report type %u\n", type);
966 return NULL;
967 }
968
969 if (id >= HID_MAX_IDS) {
970 hid_err(hid, "invalid HID report id %u\n", id);
971 return NULL;
972 }
973
974 /*
975 * Explicitly not using hid_get_report() here since it depends on
976 * ->numbered being checked, which may not always be the case when
977 * drivers go to access report values.
978 */
979 if (id == 0) {
980 /*
981 * Validating on id 0 means we should examine the first
982 * report in the list.
983 */
984 report = list_entry(
985 hid->report_enum[type].report_list.next,
986 struct hid_report, list);
987 } else {
988 report = hid->report_enum[type].report_id_hash[id];
989 }
990 if (!report) {
991 hid_err(hid, "missing %s %u\n", hid_report_names[type], id);
992 return NULL;
993 }
994 if (report->maxfield <= field_index) {
995 hid_err(hid, "not enough fields in %s %u\n",
996 hid_report_names[type], id);
997 return NULL;
998 }
999 if (report->field[field_index]->report_count < report_counts) {
1000 hid_err(hid, "not enough values in %s %u field %u\n",
1001 hid_report_names[type], id, field_index);
1002 return NULL;
1003 }
1004 return report;
1005 }
1006 EXPORT_SYMBOL_GPL(hid_validate_values);
1007
1008 static int hid_calculate_multiplier(struct hid_device *hid,
1009 struct hid_field *multiplier)
1010 {
1011 int m;
1012 __s32 v = *multiplier->value;
1013 __s32 lmin = multiplier->logical_minimum;
1014 __s32 lmax = multiplier->logical_maximum;
1015 __s32 pmin = multiplier->physical_minimum;
1016 __s32 pmax = multiplier->physical_maximum;
1017
1018 /*
1019 * "Because OS implementations will generally divide the control's
1020 * reported count by the Effective Resolution Multiplier, designers
1021 * should take care not to establish a potential Effective
1022 * Resolution Multiplier of zero."
1023 * HID Usage Table, v1.12, Section 4.3.1, p31
1024 */
1025 if (lmax - lmin == 0)
1026 return 1;
1027 /*
1028 * Handling the unit exponent is left as an exercise to whoever
1029 * finds a device where that exponent is not 0.
1030 */
1031 m = ((v - lmin)/(lmax - lmin) * (pmax - pmin) + pmin);
1032 if (unlikely(multiplier->unit_exponent != 0)) {
1033 hid_warn(hid,
1034 "unsupported Resolution Multiplier unit exponent %d\n",
1035 multiplier->unit_exponent);
1036 }
1037
1038 /* There are no devices with an effective multiplier > 255 */
1039 if (unlikely(m == 0 || m > 255 || m < -255)) {
1040 hid_warn(hid, "unsupported Resolution Multiplier %d\n", m);
1041 m = 1;
1042 }
1043
1044 return m;
1045 }
1046
1047 static void hid_apply_multiplier_to_field(struct hid_device *hid,
1048 struct hid_field *field,
1049 struct hid_collection *multiplier_collection,
1050 int effective_multiplier)
1051 {
1052 struct hid_collection *collection;
1053 struct hid_usage *usage;
1054 int i;
1055
1056 /*
1057 * If multiplier_collection is NULL, the multiplier applies
1058 * to all fields in the report.
1059 * Otherwise, it is the Logical Collection the multiplier applies to
1060 * but our field may be in a subcollection of that collection.
1061 */
1062 for (i = 0; i < field->maxusage; i++) {
1063 usage = &field->usage[i];
1064
1065 collection = &hid->collection[usage->collection_index];
1066 while (collection->parent_idx != -1 &&
1067 collection != multiplier_collection)
1068 collection = &hid->collection[collection->parent_idx];
1069
1070 if (collection->parent_idx != -1 ||
1071 multiplier_collection == NULL)
1072 usage->resolution_multiplier = effective_multiplier;
1073
1074 }
1075 }
1076
1077 static void hid_apply_multiplier(struct hid_device *hid,
1078 struct hid_field *multiplier)
1079 {
1080 struct hid_report_enum *rep_enum;
1081 struct hid_report *rep;
1082 struct hid_field *field;
1083 struct hid_collection *multiplier_collection;
1084 int effective_multiplier;
1085 int i;
1086
1087 /*
1088 * "The Resolution Multiplier control must be contained in the same
1089 * Logical Collection as the control(s) to which it is to be applied.
1090 * If no Resolution Multiplier is defined, then the Resolution
1091 * Multiplier defaults to 1. If more than one control exists in a
1092 * Logical Collection, the Resolution Multiplier is associated with
1093 * all controls in the collection. If no Logical Collection is
1094 * defined, the Resolution Multiplier is associated with all
1095 * controls in the report."
1096 * HID Usage Table, v1.12, Section 4.3.1, p30
1097 *
1098 * Thus, search from the current collection upwards until we find a
1099 * logical collection. Then search all fields for that same parent
1100 * collection. Those are the fields the multiplier applies to.
1101 *
1102 * If we have more than one multiplier, it will overwrite the
1103 * applicable fields later.
1104 */
1105 multiplier_collection = &hid->collection[multiplier->usage->collection_index];
1106 while (multiplier_collection->parent_idx != -1 &&
1107 multiplier_collection->type != HID_COLLECTION_LOGICAL)
1108 multiplier_collection = &hid->collection[multiplier_collection->parent_idx];
1109
1110 effective_multiplier = hid_calculate_multiplier(hid, multiplier);
1111
1112 rep_enum = &hid->report_enum[HID_INPUT_REPORT];
1113 list_for_each_entry(rep, &rep_enum->report_list, list) {
1114 for (i = 0; i < rep->maxfield; i++) {
1115 field = rep->field[i];
1116 hid_apply_multiplier_to_field(hid, field,
1117 multiplier_collection,
1118 effective_multiplier);
1119 }
1120 }
1121 }
1122
1123 /*
1124 * hid_setup_resolution_multiplier - set up all resolution multipliers
1125 *
1126 * @device: hid device
1127 *
1128 * Search for all Resolution Multiplier Feature Reports and apply their
1129 * value to all matching Input items. This only updates the internal struct
1130 * fields.
1131 *
1132 * The Resolution Multiplier is applied by the hardware. If the multiplier
1133 * is anything other than 1, the hardware will send pre-multiplied events
1134 * so that the same physical interaction generates an accumulated
1135 * accumulated_value = value * * multiplier
1136 * This may be achieved by sending
1137 * - "value * multiplier" for each event, or
1138 * - "value" but "multiplier" times as frequently, or
1139 * - a combination of the above
1140 * The only guarantee is that the same physical interaction always generates
1141 * an accumulated 'value * multiplier'.
1142 *
1143 * This function must be called before any event processing and after
1144 * any SetRequest to the Resolution Multiplier.
1145 */
1146 void hid_setup_resolution_multiplier(struct hid_device *hid)
1147 {
1148 struct hid_report_enum *rep_enum;
1149 struct hid_report *rep;
1150 struct hid_usage *usage;
1151 int i, j;
1152
1153 rep_enum = &hid->report_enum[HID_FEATURE_REPORT];
1154 list_for_each_entry(rep, &rep_enum->report_list, list) {
1155 for (i = 0; i < rep->maxfield; i++) {
1156 /* Ignore if report count is out of bounds. */
1157 if (rep->field[i]->report_count < 1)
1158 continue;
1159
1160 for (j = 0; j < rep->field[i]->maxusage; j++) {
1161 usage = &rep->field[i]->usage[j];
1162 if (usage->hid == HID_GD_RESOLUTION_MULTIPLIER)
1163 hid_apply_multiplier(hid,
1164 rep->field[i]);
1165 }
1166 }
1167 }
1168 }
1169 EXPORT_SYMBOL_GPL(hid_setup_resolution_multiplier);
1170
1171 /**
1172 * hid_open_report - open a driver-specific device report
1173 *
1174 * @device: hid device
1175 *
1176 * Parse a report description into a hid_device structure. Reports are
1177 * enumerated, fields are attached to these reports.
1178 * 0 returned on success, otherwise nonzero error value.
1179 *
1180 * This function (or the equivalent hid_parse() macro) should only be
1181 * called from probe() in drivers, before starting the device.
1182 */
1183 int hid_open_report(struct hid_device *device)
1184 {
1185 struct hid_parser *parser;
1186 struct hid_item item;
1187 unsigned int size;
1188 __u8 *start;
1189 __u8 *buf;
1190 __u8 *end;
1191 __u8 *next;
1192 int ret;
1193 static int (*dispatch_type[])(struct hid_parser *parser,
1194 struct hid_item *item) = {
1195 hid_parser_main,
1196 hid_parser_global,
1197 hid_parser_local,
1198 hid_parser_reserved
1199 };
1200
1201 if (WARN_ON(device->status & HID_STAT_PARSED))
1202 return -EBUSY;
1203
1204 start = device->dev_rdesc;
1205 if (WARN_ON(!start))
1206 return -ENODEV;
1207 size = device->dev_rsize;
1208
1209 buf = kmemdup(start, size, GFP_KERNEL);
1210 if (buf == NULL)
1211 return -ENOMEM;
1212
1213 if (device->driver->report_fixup)
1214 start = device->driver->report_fixup(device, buf, &size);
1215 else
1216 start = buf;
1217
1218 start = kmemdup(start, size, GFP_KERNEL);
1219 kfree(buf);
1220 if (start == NULL)
1221 return -ENOMEM;
1222
1223 device->rdesc = start;
1224 device->rsize = size;
1225
1226 parser = vzalloc(sizeof(struct hid_parser));
1227 if (!parser) {
1228 ret = -ENOMEM;
1229 goto alloc_err;
1230 }
1231
1232 parser->device = device;
1233
1234 end = start + size;
1235
1236 device->collection = kcalloc(HID_DEFAULT_NUM_COLLECTIONS,
1237 sizeof(struct hid_collection), GFP_KERNEL);
1238 if (!device->collection) {
1239 ret = -ENOMEM;
1240 goto err;
1241 }
1242 device->collection_size = HID_DEFAULT_NUM_COLLECTIONS;
1243
1244 ret = -EINVAL;
1245 while ((next = fetch_item(start, end, &item)) != NULL) {
1246 start = next;
1247
1248 if (item.format != HID_ITEM_FORMAT_SHORT) {
1249 hid_err(device, "unexpected long global item\n");
1250 goto err;
1251 }
1252
1253 if (dispatch_type[item.type](parser, &item)) {
1254 hid_err(device, "item %u %u %u %u parsing failed\n",
1255 item.format, (unsigned)item.size,
1256 (unsigned)item.type, (unsigned)item.tag);
1257 goto err;
1258 }
1259
1260 if (start == end) {
1261 if (parser->collection_stack_ptr) {
1262 hid_err(device, "unbalanced collection at end of report description\n");
1263 goto err;
1264 }
1265 if (parser->local.delimiter_depth) {
1266 hid_err(device, "unbalanced delimiter at end of report description\n");
1267 goto err;
1268 }
1269
1270 /*
1271 * fetch initial values in case the device's
1272 * default multiplier isn't the recommended 1
1273 */
1274 hid_setup_resolution_multiplier(device);
1275
1276 kfree(parser->collection_stack);
1277 vfree(parser);
1278 device->status |= HID_STAT_PARSED;
1279
1280 return 0;
1281 }
1282 }
1283
1284 hid_err(device, "item fetching failed at offset %u/%u\n",
1285 size - (unsigned int)(end - start), size);
1286 err:
1287 kfree(parser->collection_stack);
1288 alloc_err:
1289 vfree(parser);
1290 hid_close_report(device);
1291 return ret;
1292 }
1293 EXPORT_SYMBOL_GPL(hid_open_report);
1294
1295 /*
1296 * Convert a signed n-bit integer to signed 32-bit integer. Common
1297 * cases are done through the compiler, the screwed things has to be
1298 * done by hand.
1299 */
1300
1301 static s32 snto32(__u32 value, unsigned n)
1302 {
1303 switch (n) {
1304 case 8: return ((__s8)value);
1305 case 16: return ((__s16)value);
1306 case 32: return ((__s32)value);
1307 }
1308 return value & (1 << (n - 1)) ? value | (~0U << n) : value;
1309 }
1310
1311 s32 hid_snto32(__u32 value, unsigned n)
1312 {
1313 return snto32(value, n);
1314 }
1315 EXPORT_SYMBOL_GPL(hid_snto32);
1316
1317 /*
1318 * Convert a signed 32-bit integer to a signed n-bit integer.
1319 */
1320
1321 static u32 s32ton(__s32 value, unsigned n)
1322 {
1323 s32 a = value >> (n - 1);
1324 if (a && a != -1)
1325 return value < 0 ? 1 << (n - 1) : (1 << (n - 1)) - 1;
1326 return value & ((1 << n) - 1);
1327 }
1328
1329 /*
1330 * Extract/implement a data field from/to a little endian report (bit array).
1331 *
1332 * Code sort-of follows HID spec:
1333 * http://www.usb.org/developers/hidpage/HID1_11.pdf
1334 *
1335 * While the USB HID spec allows unlimited length bit fields in "report
1336 * descriptors", most devices never use more than 16 bits.
1337 * One model of UPS is claimed to report "LINEV" as a 32-bit field.
1338 * Search linux-kernel and linux-usb-devel archives for "hid-core extract".
1339 */
1340
1341 static u32 __extract(u8 *report, unsigned offset, int n)
1342 {
1343 unsigned int idx = offset / 8;
1344 unsigned int bit_nr = 0;
1345 unsigned int bit_shift = offset % 8;
1346 int bits_to_copy = 8 - bit_shift;
1347 u32 value = 0;
1348 u32 mask = n < 32 ? (1U << n) - 1 : ~0U;
1349
1350 while (n > 0) {
1351 value |= ((u32)report[idx] >> bit_shift) << bit_nr;
1352 n -= bits_to_copy;
1353 bit_nr += bits_to_copy;
1354 bits_to_copy = 8;
1355 bit_shift = 0;
1356 idx++;
1357 }
1358
1359 return value & mask;
1360 }
1361
1362 u32 hid_field_extract(const struct hid_device *hid, u8 *report,
1363 unsigned offset, unsigned n)
1364 {
1365 if (n > 32) {
1366 hid_warn_once(hid, "%s() called with n (%d) > 32! (%s)\n",
1367 __func__, n, current->comm);
1368 n = 32;
1369 }
1370
1371 return __extract(report, offset, n);
1372 }
1373 EXPORT_SYMBOL_GPL(hid_field_extract);
1374
1375 /*
1376 * "implement" : set bits in a little endian bit stream.
1377 * Same concepts as "extract" (see comments above).
1378 * The data mangled in the bit stream remains in little endian
1379 * order the whole time. It make more sense to talk about
1380 * endianness of register values by considering a register
1381 * a "cached" copy of the little endian bit stream.
1382 */
1383
1384 static void __implement(u8 *report, unsigned offset, int n, u32 value)
1385 {
1386 unsigned int idx = offset / 8;
1387 unsigned int bit_shift = offset % 8;
1388 int bits_to_set = 8 - bit_shift;
1389
1390 while (n - bits_to_set >= 0) {
1391 report[idx] &= ~(0xff << bit_shift);
1392 report[idx] |= value << bit_shift;
1393 value >>= bits_to_set;
1394 n -= bits_to_set;
1395 bits_to_set = 8;
1396 bit_shift = 0;
1397 idx++;
1398 }
1399
1400 /* last nibble */
1401 if (n) {
1402 u8 bit_mask = ((1U << n) - 1);
1403 report[idx] &= ~(bit_mask << bit_shift);
1404 report[idx] |= value << bit_shift;
1405 }
1406 }
1407
1408 static void implement(const struct hid_device *hid, u8 *report,
1409 unsigned offset, unsigned n, u32 value)
1410 {
1411 if (unlikely(n > 32)) {
1412 hid_warn(hid, "%s() called with n (%d) > 32! (%s)\n",
1413 __func__, n, current->comm);
1414 n = 32;
1415 } else if (n < 32) {
1416 u32 m = (1U << n) - 1;
1417
1418 if (unlikely(value > m)) {
1419 hid_warn(hid,
1420 "%s() called with too large value %d (n: %d)! (%s)\n",
1421 __func__, value, n, current->comm);
1422 WARN_ON(1);
1423 value &= m;
1424 }
1425 }
1426
1427 __implement(report, offset, n, value);
1428 }
1429
1430 /*
1431 * Search an array for a value.
1432 */
1433
1434 static int search(__s32 *array, __s32 value, unsigned n)
1435 {
1436 while (n--) {
1437 if (*array++ == value)
1438 return 0;
1439 }
1440 return -1;
1441 }
1442
1443 /**
1444 * hid_match_report - check if driver's raw_event should be called
1445 *
1446 * @hid: hid device
1447 * @report_type: type to match against
1448 *
1449 * compare hid->driver->report_table->report_type to report->type
1450 */
1451 static int hid_match_report(struct hid_device *hid, struct hid_report *report)
1452 {
1453 const struct hid_report_id *id = hid->driver->report_table;
1454
1455 if (!id) /* NULL means all */
1456 return 1;
1457
1458 for (; id->report_type != HID_TERMINATOR; id++)
1459 if (id->report_type == HID_ANY_ID ||
1460 id->report_type == report->type)
1461 return 1;
1462 return 0;
1463 }
1464
1465 /**
1466 * hid_match_usage - check if driver's event should be called
1467 *
1468 * @hid: hid device
1469 * @usage: usage to match against
1470 *
1471 * compare hid->driver->usage_table->usage_{type,code} to
1472 * usage->usage_{type,code}
1473 */
1474 static int hid_match_usage(struct hid_device *hid, struct hid_usage *usage)
1475 {
1476 const struct hid_usage_id *id = hid->driver->usage_table;
1477
1478 if (!id) /* NULL means all */
1479 return 1;
1480
1481 for (; id->usage_type != HID_ANY_ID - 1; id++)
1482 if ((id->usage_hid == HID_ANY_ID ||
1483 id->usage_hid == usage->hid) &&
1484 (id->usage_type == HID_ANY_ID ||
1485 id->usage_type == usage->type) &&
1486 (id->usage_code == HID_ANY_ID ||
1487 id->usage_code == usage->code))
1488 return 1;
1489 return 0;
1490 }
1491
1492 static void hid_process_event(struct hid_device *hid, struct hid_field *field,
1493 struct hid_usage *usage, __s32 value, int interrupt)
1494 {
1495 struct hid_driver *hdrv = hid->driver;
1496 int ret;
1497
1498 if (!list_empty(&hid->debug_list))
1499 hid_dump_input(hid, usage, value);
1500
1501 if (hdrv && hdrv->event && hid_match_usage(hid, usage)) {
1502 ret = hdrv->event(hid, field, usage, value);
1503 if (ret != 0) {
1504 if (ret < 0)
1505 hid_err(hid, "%s's event failed with %d\n",
1506 hdrv->name, ret);
1507 return;
1508 }
1509 }
1510
1511 if (hid->claimed & HID_CLAIMED_INPUT)
1512 hidinput_hid_event(hid, field, usage, value);
1513 if (hid->claimed & HID_CLAIMED_HIDDEV && interrupt && hid->hiddev_hid_event)
1514 hid->hiddev_hid_event(hid, field, usage, value);
1515 }
1516
1517 /*
1518 * Analyse a received field, and fetch the data from it. The field
1519 * content is stored for next report processing (we do differential
1520 * reporting to the layer).
1521 */
1522
1523 static void hid_input_field(struct hid_device *hid, struct hid_field *field,
1524 __u8 *data, int interrupt)
1525 {
1526 unsigned n;
1527 unsigned count = field->report_count;
1528 unsigned offset = field->report_offset;
1529 unsigned size = field->report_size;
1530 __s32 min = field->logical_minimum;
1531 __s32 max = field->logical_maximum;
1532 __s32 *value;
1533
1534 value = kmalloc_array(count, sizeof(__s32), GFP_ATOMIC);
1535 if (!value)
1536 return;
1537
1538 for (n = 0; n < count; n++) {
1539
1540 value[n] = min < 0 ?
1541 snto32(hid_field_extract(hid, data, offset + n * size,
1542 size), size) :
1543 hid_field_extract(hid, data, offset + n * size, size);
1544
1545 /* Ignore report if ErrorRollOver */
1546 if (!(field->flags & HID_MAIN_ITEM_VARIABLE) &&
1547 value[n] >= min && value[n] <= max &&
1548 value[n] - min < field->maxusage &&
1549 field->usage[value[n] - min].hid == HID_UP_KEYBOARD + 1)
1550 goto exit;
1551 }
1552
1553 for (n = 0; n < count; n++) {
1554
1555 if (HID_MAIN_ITEM_VARIABLE & field->flags) {
1556 hid_process_event(hid, field, &field->usage[n], value[n], interrupt);
1557 continue;
1558 }
1559
1560 if (field->value[n] >= min && field->value[n] <= max
1561 && field->value[n] - min < field->maxusage
1562 && field->usage[field->value[n] - min].hid
1563 && search(value, field->value[n], count))
1564 hid_process_event(hid, field, &field->usage[field->value[n] - min], 0, interrupt);
1565
1566 if (value[n] >= min && value[n] <= max
1567 && value[n] - min < field->maxusage
1568 && field->usage[value[n] - min].hid
1569 && search(field->value, value[n], count))
1570 hid_process_event(hid, field, &field->usage[value[n] - min], 1, interrupt);
1571 }
1572
1573 memcpy(field->value, value, count * sizeof(__s32));
1574 exit:
1575 kfree(value);
1576 }
1577
1578 /*
1579 * Output the field into the report.
1580 */
1581
1582 static void hid_output_field(const struct hid_device *hid,
1583 struct hid_field *field, __u8 *data)
1584 {
1585 unsigned count = field->report_count;
1586 unsigned offset = field->report_offset;
1587 unsigned size = field->report_size;
1588 unsigned n;
1589
1590 for (n = 0; n < count; n++) {
1591 if (field->logical_minimum < 0) /* signed values */
1592 implement(hid, data, offset + n * size, size,
1593 s32ton(field->value[n], size));
1594 else /* unsigned values */
1595 implement(hid, data, offset + n * size, size,
1596 field->value[n]);
1597 }
1598 }
1599
1600 /*
1601 * Create a report. 'data' has to be allocated using
1602 * hid_alloc_report_buf() so that it has proper size.
1603 */
1604
1605 void hid_output_report(struct hid_report *report, __u8 *data)
1606 {
1607 unsigned n;
1608
1609 if (report->id > 0)
1610 *data++ = report->id;
1611
1612 memset(data, 0, ((report->size - 1) >> 3) + 1);
1613 for (n = 0; n < report->maxfield; n++)
1614 hid_output_field(report->device, report->field[n], data);
1615 }
1616 EXPORT_SYMBOL_GPL(hid_output_report);
1617
1618 /*
1619 * Allocator for buffer that is going to be passed to hid_output_report()
1620 */
1621 u8 *hid_alloc_report_buf(struct hid_report *report, gfp_t flags)
1622 {
1623 /*
1624 * 7 extra bytes are necessary to achieve proper functionality
1625 * of implement() working on 8 byte chunks
1626 */
1627
1628 u32 len = hid_report_len(report) + 7;
1629
1630 return kmalloc(len, flags);
1631 }
1632 EXPORT_SYMBOL_GPL(hid_alloc_report_buf);
1633
1634 /*
1635 * Set a field value. The report this field belongs to has to be
1636 * created and transferred to the device, to set this value in the
1637 * device.
1638 */
1639
1640 int hid_set_field(struct hid_field *field, unsigned offset, __s32 value)
1641 {
1642 unsigned size;
1643
1644 if (!field)
1645 return -1;
1646
1647 size = field->report_size;
1648
1649 hid_dump_input(field->report->device, field->usage + offset, value);
1650
1651 if (offset >= field->report_count) {
1652 hid_err(field->report->device, "offset (%d) exceeds report_count (%d)\n",
1653 offset, field->report_count);
1654 return -1;
1655 }
1656 if (field->logical_minimum < 0) {
1657 if (value != snto32(s32ton(value, size), size)) {
1658 hid_err(field->report->device, "value %d is out of range\n", value);
1659 return -1;
1660 }
1661 }
1662 field->value[offset] = value;
1663 return 0;
1664 }
1665 EXPORT_SYMBOL_GPL(hid_set_field);
1666
1667 static struct hid_report *hid_get_report(struct hid_report_enum *report_enum,
1668 const u8 *data)
1669 {
1670 struct hid_report *report;
1671 unsigned int n = 0; /* Normally report number is 0 */
1672
1673 /* Device uses numbered reports, data[0] is report number */
1674 if (report_enum->numbered)
1675 n = *data;
1676
1677 report = report_enum->report_id_hash[n];
1678 if (report == NULL)
1679 dbg_hid("undefined report_id %u received\n", n);
1680
1681 return report;
1682 }
1683
1684 /*
1685 * Implement a generic .request() callback, using .raw_request()
1686 * DO NOT USE in hid drivers directly, but through hid_hw_request instead.
1687 */
1688 int __hid_request(struct hid_device *hid, struct hid_report *report,
1689 int reqtype)
1690 {
1691 char *buf;
1692 int ret;
1693 u32 len;
1694
1695 buf = hid_alloc_report_buf(report, GFP_KERNEL);
1696 if (!buf)
1697 return -ENOMEM;
1698
1699 len = hid_report_len(report);
1700
1701 if (reqtype == HID_REQ_SET_REPORT)
1702 hid_output_report(report, buf);
1703
1704 ret = hid->ll_driver->raw_request(hid, report->id, buf, len,
1705 report->type, reqtype);
1706 if (ret < 0) {
1707 dbg_hid("unable to complete request: %d\n", ret);
1708 goto out;
1709 }
1710
1711 if (reqtype == HID_REQ_GET_REPORT)
1712 hid_input_report(hid, report->type, buf, ret, 0);
1713
1714 ret = 0;
1715
1716 out:
1717 kfree(buf);
1718 return ret;
1719 }
1720 EXPORT_SYMBOL_GPL(__hid_request);
1721
1722 int hid_report_raw_event(struct hid_device *hid, int type, u8 *data, u32 size,
1723 int interrupt)
1724 {
1725 struct hid_report_enum *report_enum = hid->report_enum + type;
1726 struct hid_report *report;
1727 struct hid_driver *hdrv;
1728 unsigned int a;
1729 u32 rsize, csize = size;
1730 u8 *cdata = data;
1731 int ret = 0;
1732
1733 report = hid_get_report(report_enum, data);
1734 if (!report)
1735 goto out;
1736
1737 if (report_enum->numbered) {
1738 cdata++;
1739 csize--;
1740 }
1741
1742 rsize = ((report->size - 1) >> 3) + 1;
1743
1744 if (rsize > HID_MAX_BUFFER_SIZE)
1745 rsize = HID_MAX_BUFFER_SIZE;
1746
1747 if (csize < rsize) {
1748 dbg_hid("report %d is too short, (%d < %d)\n", report->id,
1749 csize, rsize);
1750 memset(cdata + csize, 0, rsize - csize);
1751 }
1752
1753 if ((hid->claimed & HID_CLAIMED_HIDDEV) && hid->hiddev_report_event)
1754 hid->hiddev_report_event(hid, report);
1755 if (hid->claimed & HID_CLAIMED_HIDRAW) {
1756 ret = hidraw_report_event(hid, data, size);
1757 if (ret)
1758 goto out;
1759 }
1760
1761 if (hid->claimed != HID_CLAIMED_HIDRAW && report->maxfield) {
1762 for (a = 0; a < report->maxfield; a++)
1763 hid_input_field(hid, report->field[a], cdata, interrupt);
1764 hdrv = hid->driver;
1765 if (hdrv && hdrv->report)
1766 hdrv->report(hid, report);
1767 }
1768
1769 if (hid->claimed & HID_CLAIMED_INPUT)
1770 hidinput_report_event(hid, report);
1771 out:
1772 return ret;
1773 }
1774 EXPORT_SYMBOL_GPL(hid_report_raw_event);
1775
1776 /**
1777 * hid_input_report - report data from lower layer (usb, bt...)
1778 *
1779 * @hid: hid device
1780 * @type: HID report type (HID_*_REPORT)
1781 * @data: report contents
1782 * @size: size of data parameter
1783 * @interrupt: distinguish between interrupt and control transfers
1784 *
1785 * This is data entry for lower layers.
1786 */
1787 int hid_input_report(struct hid_device *hid, int type, u8 *data, u32 size, int interrupt)
1788 {
1789 struct hid_report_enum *report_enum;
1790 struct hid_driver *hdrv;
1791 struct hid_report *report;
1792 int ret = 0;
1793
1794 if (!hid)
1795 return -ENODEV;
1796
1797 if (down_trylock(&hid->driver_input_lock))
1798 return -EBUSY;
1799
1800 if (!hid->driver) {
1801 ret = -ENODEV;
1802 goto unlock;
1803 }
1804 report_enum = hid->report_enum + type;
1805 hdrv = hid->driver;
1806
1807 if (!size) {
1808 dbg_hid("empty report\n");
1809 ret = -1;
1810 goto unlock;
1811 }
1812
1813 /* Avoid unnecessary overhead if debugfs is disabled */
1814 if (!list_empty(&hid->debug_list))
1815 hid_dump_report(hid, type, data, size);
1816
1817 report = hid_get_report(report_enum, data);
1818
1819 if (!report) {
1820 ret = -1;
1821 goto unlock;
1822 }
1823
1824 if (hdrv && hdrv->raw_event && hid_match_report(hid, report)) {
1825 ret = hdrv->raw_event(hid, report, data, size);
1826 if (ret < 0)
1827 goto unlock;
1828 }
1829
1830 ret = hid_report_raw_event(hid, type, data, size, interrupt);
1831
1832 unlock:
1833 up(&hid->driver_input_lock);
1834 return ret;
1835 }
1836 EXPORT_SYMBOL_GPL(hid_input_report);
1837
1838 bool hid_match_one_id(const struct hid_device *hdev,
1839 const struct hid_device_id *id)
1840 {
1841 return (id->bus == HID_BUS_ANY || id->bus == hdev->bus) &&
1842 (id->group == HID_GROUP_ANY || id->group == hdev->group) &&
1843 (id->vendor == HID_ANY_ID || id->vendor == hdev->vendor) &&
1844 (id->product == HID_ANY_ID || id->product == hdev->product);
1845 }
1846
1847 const struct hid_device_id *hid_match_id(const struct hid_device *hdev,
1848 const struct hid_device_id *id)
1849 {
1850 for (; id->bus; id++)
1851 if (hid_match_one_id(hdev, id))
1852 return id;
1853
1854 return NULL;
1855 }
1856
1857 static const struct hid_device_id hid_hiddev_list[] = {
1858 { HID_USB_DEVICE(USB_VENDOR_ID_MGE, USB_DEVICE_ID_MGE_UPS) },
1859 { HID_USB_DEVICE(USB_VENDOR_ID_MGE, USB_DEVICE_ID_MGE_UPS1) },
1860 { }
1861 };
1862
1863 static bool hid_hiddev(struct hid_device *hdev)
1864 {
1865 return !!hid_match_id(hdev, hid_hiddev_list);
1866 }
1867
1868
1869 static ssize_t
1870 read_report_descriptor(struct file *filp, struct kobject *kobj,
1871 struct bin_attribute *attr,
1872 char *buf, loff_t off, size_t count)
1873 {
1874 struct device *dev = kobj_to_dev(kobj);
1875 struct hid_device *hdev = to_hid_device(dev);
1876
1877 if (off >= hdev->rsize)
1878 return 0;
1879
1880 if (off + count > hdev->rsize)
1881 count = hdev->rsize - off;
1882
1883 memcpy(buf, hdev->rdesc + off, count);
1884
1885 return count;
1886 }
1887
1888 static ssize_t
1889 show_country(struct device *dev, struct device_attribute *attr,
1890 char *buf)
1891 {
1892 struct hid_device *hdev = to_hid_device(dev);
1893
1894 return sprintf(buf, "%02x\n", hdev->country & 0xff);
1895 }
1896
1897 static struct bin_attribute dev_bin_attr_report_desc = {
1898 .attr = { .name = "report_descriptor", .mode = 0444 },
1899 .read = read_report_descriptor,
1900 .size = HID_MAX_DESCRIPTOR_SIZE,
1901 };
1902
1903 static const struct device_attribute dev_attr_country = {
1904 .attr = { .name = "country", .mode = 0444 },
1905 .show = show_country,
1906 };
1907
1908 int hid_connect(struct hid_device *hdev, unsigned int connect_mask)
1909 {
1910 static const char *types[] = { "Device", "Pointer", "Mouse", "Device",
1911 "Joystick", "Gamepad", "Keyboard", "Keypad",
1912 "Multi-Axis Controller"
1913 };
1914 const char *type, *bus;
1915 char buf[64] = "";
1916 unsigned int i;
1917 int len;
1918 int ret;
1919
1920 if (hdev->quirks & HID_QUIRK_HIDDEV_FORCE)
1921 connect_mask |= (HID_CONNECT_HIDDEV_FORCE | HID_CONNECT_HIDDEV);
1922 if (hdev->quirks & HID_QUIRK_HIDINPUT_FORCE)
1923 connect_mask |= HID_CONNECT_HIDINPUT_FORCE;
1924 if (hdev->bus != BUS_USB)
1925 connect_mask &= ~HID_CONNECT_HIDDEV;
1926 if (hid_hiddev(hdev))
1927 connect_mask |= HID_CONNECT_HIDDEV_FORCE;
1928
1929 if ((connect_mask & HID_CONNECT_HIDINPUT) && !hidinput_connect(hdev,
1930 connect_mask & HID_CONNECT_HIDINPUT_FORCE))
1931 hdev->claimed |= HID_CLAIMED_INPUT;
1932
1933 if ((connect_mask & HID_CONNECT_HIDDEV) && hdev->hiddev_connect &&
1934 !hdev->hiddev_connect(hdev,
1935 connect_mask & HID_CONNECT_HIDDEV_FORCE))
1936 hdev->claimed |= HID_CLAIMED_HIDDEV;
1937 if ((connect_mask & HID_CONNECT_HIDRAW) && !hidraw_connect(hdev))
1938 hdev->claimed |= HID_CLAIMED_HIDRAW;
1939
1940 if (connect_mask & HID_CONNECT_DRIVER)
1941 hdev->claimed |= HID_CLAIMED_DRIVER;
1942
1943 /* Drivers with the ->raw_event callback set are not required to connect
1944 * to any other listener. */
1945 if (!hdev->claimed && !hdev->driver->raw_event) {
1946 hid_err(hdev, "device has no listeners, quitting\n");
1947 return -ENODEV;
1948 }
1949
1950 if ((hdev->claimed & HID_CLAIMED_INPUT) &&
1951 (connect_mask & HID_CONNECT_FF) && hdev->ff_init)
1952 hdev->ff_init(hdev);
1953
1954 len = 0;
1955 if (hdev->claimed & HID_CLAIMED_INPUT)
1956 len += sprintf(buf + len, "input");
1957 if (hdev->claimed & HID_CLAIMED_HIDDEV)
1958 len += sprintf(buf + len, "%shiddev%d", len ? "," : "",
1959 ((struct hiddev *)hdev->hiddev)->minor);
1960 if (hdev->claimed & HID_CLAIMED_HIDRAW)
1961 len += sprintf(buf + len, "%shidraw%d", len ? "," : "",
1962 ((struct hidraw *)hdev->hidraw)->minor);
1963
1964 type = "Device";
1965 for (i = 0; i < hdev->maxcollection; i++) {
1966 struct hid_collection *col = &hdev->collection[i];
1967 if (col->type == HID_COLLECTION_APPLICATION &&
1968 (col->usage & HID_USAGE_PAGE) == HID_UP_GENDESK &&
1969 (col->usage & 0xffff) < ARRAY_SIZE(types)) {
1970 type = types[col->usage & 0xffff];
1971 break;
1972 }
1973 }
1974
1975 switch (hdev->bus) {
1976 case BUS_USB:
1977 bus = "USB";
1978 break;
1979 case BUS_BLUETOOTH:
1980 bus = "BLUETOOTH";
1981 break;
1982 case BUS_I2C:
1983 bus = "I2C";
1984 break;
1985 default:
1986 bus = "<UNKNOWN>";
1987 }
1988
1989 ret = device_create_file(&hdev->dev, &dev_attr_country);
1990 if (ret)
1991 hid_warn(hdev,
1992 "can't create sysfs country code attribute err: %d\n", ret);
1993
1994 hid_info(hdev, "%s: %s HID v%x.%02x %s [%s] on %s\n",
1995 buf, bus, hdev->version >> 8, hdev->version & 0xff,
1996 type, hdev->name, hdev->phys);
1997
1998 return 0;
1999 }
2000 EXPORT_SYMBOL_GPL(hid_connect);
2001
2002 void hid_disconnect(struct hid_device *hdev)
2003 {
2004 device_remove_file(&hdev->dev, &dev_attr_country);
2005 if (hdev->claimed & HID_CLAIMED_INPUT)
2006 hidinput_disconnect(hdev);
2007 if (hdev->claimed & HID_CLAIMED_HIDDEV)
2008 hdev->hiddev_disconnect(hdev);
2009 if (hdev->claimed & HID_CLAIMED_HIDRAW)
2010 hidraw_disconnect(hdev);
2011 hdev->claimed = 0;
2012 }
2013 EXPORT_SYMBOL_GPL(hid_disconnect);
2014
2015 /**
2016 * hid_hw_start - start underlying HW
2017 * @hdev: hid device
2018 * @connect_mask: which outputs to connect, see HID_CONNECT_*
2019 *
2020 * Call this in probe function *after* hid_parse. This will setup HW
2021 * buffers and start the device (if not defeirred to device open).
2022 * hid_hw_stop must be called if this was successful.
2023 */
2024 int hid_hw_start(struct hid_device *hdev, unsigned int connect_mask)
2025 {
2026 int error;
2027
2028 error = hdev->ll_driver->start(hdev);
2029 if (error)
2030 return error;
2031
2032 if (connect_mask) {
2033 error = hid_connect(hdev, connect_mask);
2034 if (error) {
2035 hdev->ll_driver->stop(hdev);
2036 return error;
2037 }
2038 }
2039
2040 return 0;
2041 }
2042 EXPORT_SYMBOL_GPL(hid_hw_start);
2043
2044 /**
2045 * hid_hw_stop - stop underlying HW
2046 * @hdev: hid device
2047 *
2048 * This is usually called from remove function or from probe when something
2049 * failed and hid_hw_start was called already.
2050 */
2051 void hid_hw_stop(struct hid_device *hdev)
2052 {
2053 hid_disconnect(hdev);
2054 hdev->ll_driver->stop(hdev);
2055 }
2056 EXPORT_SYMBOL_GPL(hid_hw_stop);
2057
2058 /**
2059 * hid_hw_open - signal underlying HW to start delivering events
2060 * @hdev: hid device
2061 *
2062 * Tell underlying HW to start delivering events from the device.
2063 * This function should be called sometime after successful call
2064 * to hid_hw_start().
2065 */
2066 int hid_hw_open(struct hid_device *hdev)
2067 {
2068 int ret;
2069
2070 ret = mutex_lock_killable(&hdev->ll_open_lock);
2071 if (ret)
2072 return ret;
2073
2074 if (!hdev->ll_open_count++) {
2075 ret = hdev->ll_driver->open(hdev);
2076 if (ret)
2077 hdev->ll_open_count--;
2078 }
2079
2080 mutex_unlock(&hdev->ll_open_lock);
2081 return ret;
2082 }
2083 EXPORT_SYMBOL_GPL(hid_hw_open);
2084
2085 /**
2086 * hid_hw_close - signal underlaying HW to stop delivering events
2087 *
2088 * @hdev: hid device
2089 *
2090 * This function indicates that we are not interested in the events
2091 * from this device anymore. Delivery of events may or may not stop,
2092 * depending on the number of users still outstanding.
2093 */
2094 void hid_hw_close(struct hid_device *hdev)
2095 {
2096 mutex_lock(&hdev->ll_open_lock);
2097 if (!--hdev->ll_open_count)
2098 hdev->ll_driver->close(hdev);
2099 mutex_unlock(&hdev->ll_open_lock);
2100 }
2101 EXPORT_SYMBOL_GPL(hid_hw_close);
2102
2103 struct hid_dynid {
2104 struct list_head list;
2105 struct hid_device_id id;
2106 };
2107
2108 /**
2109 * store_new_id - add a new HID device ID to this driver and re-probe devices
2110 * @driver: target device driver
2111 * @buf: buffer for scanning device ID data
2112 * @count: input size
2113 *
2114 * Adds a new dynamic hid device ID to this driver,
2115 * and causes the driver to probe for all devices again.
2116 */
2117 static ssize_t new_id_store(struct device_driver *drv, const char *buf,
2118 size_t count)
2119 {
2120 struct hid_driver *hdrv = to_hid_driver(drv);
2121 struct hid_dynid *dynid;
2122 __u32 bus, vendor, product;
2123 unsigned long driver_data = 0;
2124 int ret;
2125
2126 ret = sscanf(buf, "%x %x %x %lx",
2127 &bus, &vendor, &product, &driver_data);
2128 if (ret < 3)
2129 return -EINVAL;
2130
2131 dynid = kzalloc(sizeof(*dynid), GFP_KERNEL);
2132 if (!dynid)
2133 return -ENOMEM;
2134
2135 dynid->id.bus = bus;
2136 dynid->id.group = HID_GROUP_ANY;
2137 dynid->id.vendor = vendor;
2138 dynid->id.product = product;
2139 dynid->id.driver_data = driver_data;
2140
2141 spin_lock(&hdrv->dyn_lock);
2142 list_add_tail(&dynid->list, &hdrv->dyn_list);
2143 spin_unlock(&hdrv->dyn_lock);
2144
2145 ret = driver_attach(&hdrv->driver);
2146
2147 return ret ? : count;
2148 }
2149 static DRIVER_ATTR_WO(new_id);
2150
2151 static struct attribute *hid_drv_attrs[] = {
2152 &driver_attr_new_id.attr,
2153 NULL,
2154 };
2155 ATTRIBUTE_GROUPS(hid_drv);
2156
2157 static void hid_free_dynids(struct hid_driver *hdrv)
2158 {
2159 struct hid_dynid *dynid, *n;
2160
2161 spin_lock(&hdrv->dyn_lock);
2162 list_for_each_entry_safe(dynid, n, &hdrv->dyn_list, list) {
2163 list_del(&dynid->list);
2164 kfree(dynid);
2165 }
2166 spin_unlock(&hdrv->dyn_lock);
2167 }
2168
2169 const struct hid_device_id *hid_match_device(struct hid_device *hdev,
2170 struct hid_driver *hdrv)
2171 {
2172 struct hid_dynid *dynid;
2173
2174 spin_lock(&hdrv->dyn_lock);
2175 list_for_each_entry(dynid, &hdrv->dyn_list, list) {
2176 if (hid_match_one_id(hdev, &dynid->id)) {
2177 spin_unlock(&hdrv->dyn_lock);
2178 return &dynid->id;
2179 }
2180 }
2181 spin_unlock(&hdrv->dyn_lock);
2182
2183 return hid_match_id(hdev, hdrv->id_table);
2184 }
2185 EXPORT_SYMBOL_GPL(hid_match_device);
2186
2187 static int hid_bus_match(struct device *dev, struct device_driver *drv)
2188 {
2189 struct hid_driver *hdrv = to_hid_driver(drv);
2190 struct hid_device *hdev = to_hid_device(dev);
2191
2192 return hid_match_device(hdev, hdrv) != NULL;
2193 }
2194
2195 /**
2196 * hid_compare_device_paths - check if both devices share the same path
2197 * @hdev_a: hid device
2198 * @hdev_b: hid device
2199 * @separator: char to use as separator
2200 *
2201 * Check if two devices share the same path up to the last occurrence of
2202 * the separator char. Both paths must exist (i.e., zero-length paths
2203 * don't match).
2204 */
2205 bool hid_compare_device_paths(struct hid_device *hdev_a,
2206 struct hid_device *hdev_b, char separator)
2207 {
2208 int n1 = strrchr(hdev_a->phys, separator) - hdev_a->phys;
2209 int n2 = strrchr(hdev_b->phys, separator) - hdev_b->phys;
2210
2211 if (n1 != n2 || n1 <= 0 || n2 <= 0)
2212 return false;
2213
2214 return !strncmp(hdev_a->phys, hdev_b->phys, n1);
2215 }
2216 EXPORT_SYMBOL_GPL(hid_compare_device_paths);
2217
2218 static int hid_device_probe(struct device *dev)
2219 {
2220 struct hid_driver *hdrv = to_hid_driver(dev->driver);
2221 struct hid_device *hdev = to_hid_device(dev);
2222 const struct hid_device_id *id;
2223 int ret = 0;
2224
2225 if (down_interruptible(&hdev->driver_input_lock)) {
2226 ret = -EINTR;
2227 goto end;
2228 }
2229 hdev->io_started = false;
2230
2231 clear_bit(ffs(HID_STAT_REPROBED), &hdev->status);
2232
2233 if (!hdev->driver) {
2234 id = hid_match_device(hdev, hdrv);
2235 if (id == NULL) {
2236 ret = -ENODEV;
2237 goto unlock;
2238 }
2239
2240 if (hdrv->match) {
2241 if (!hdrv->match(hdev, hid_ignore_special_drivers)) {
2242 ret = -ENODEV;
2243 goto unlock;
2244 }
2245 } else {
2246 /*
2247 * hid-generic implements .match(), so if
2248 * hid_ignore_special_drivers is set, we can safely
2249 * return.
2250 */
2251 if (hid_ignore_special_drivers) {
2252 ret = -ENODEV;
2253 goto unlock;
2254 }
2255 }
2256
2257 /* reset the quirks that has been previously set */
2258 hdev->quirks = hid_lookup_quirk(hdev);
2259 hdev->driver = hdrv;
2260 if (hdrv->probe) {
2261 ret = hdrv->probe(hdev, id);
2262 } else { /* default probe */
2263 ret = hid_open_report(hdev);
2264 if (!ret)
2265 ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
2266 }
2267 if (ret) {
2268 hid_close_report(hdev);
2269 hdev->driver = NULL;
2270 }
2271 }
2272 unlock:
2273 if (!hdev->io_started)
2274 up(&hdev->driver_input_lock);
2275 end:
2276 return ret;
2277 }
2278
2279 static int hid_device_remove(struct device *dev)
2280 {
2281 struct hid_device *hdev = to_hid_device(dev);
2282 struct hid_driver *hdrv;
2283 int ret = 0;
2284
2285 if (down_interruptible(&hdev->driver_input_lock)) {
2286 ret = -EINTR;
2287 goto end;
2288 }
2289 hdev->io_started = false;
2290
2291 hdrv = hdev->driver;
2292 if (hdrv) {
2293 if (hdrv->remove)
2294 hdrv->remove(hdev);
2295 else /* default remove */
2296 hid_hw_stop(hdev);
2297 hid_close_report(hdev);
2298 hdev->driver = NULL;
2299 }
2300
2301 if (!hdev->io_started)
2302 up(&hdev->driver_input_lock);
2303 end:
2304 return ret;
2305 }
2306
2307 static ssize_t modalias_show(struct device *dev, struct device_attribute *a,
2308 char *buf)
2309 {
2310 struct hid_device *hdev = container_of(dev, struct hid_device, dev);
2311
2312 return scnprintf(buf, PAGE_SIZE, "hid:b%04Xg%04Xv%08Xp%08X\n",
2313 hdev->bus, hdev->group, hdev->vendor, hdev->product);
2314 }
2315 static DEVICE_ATTR_RO(modalias);
2316
2317 static struct attribute *hid_dev_attrs[] = {
2318 &dev_attr_modalias.attr,
2319 NULL,
2320 };
2321 static struct bin_attribute *hid_dev_bin_attrs[] = {
2322 &dev_bin_attr_report_desc,
2323 NULL
2324 };
2325 static const struct attribute_group hid_dev_group = {
2326 .attrs = hid_dev_attrs,
2327 .bin_attrs = hid_dev_bin_attrs,
2328 };
2329 __ATTRIBUTE_GROUPS(hid_dev);
2330
2331 static int hid_uevent(struct device *dev, struct kobj_uevent_env *env)
2332 {
2333 struct hid_device *hdev = to_hid_device(dev);
2334
2335 if (add_uevent_var(env, "HID_ID=%04X:%08X:%08X",
2336 hdev->bus, hdev->vendor, hdev->product))
2337 return -ENOMEM;
2338
2339 if (add_uevent_var(env, "HID_NAME=%s", hdev->name))
2340 return -ENOMEM;
2341
2342 if (add_uevent_var(env, "HID_PHYS=%s", hdev->phys))
2343 return -ENOMEM;
2344
2345 if (add_uevent_var(env, "HID_UNIQ=%s", hdev->uniq))
2346 return -ENOMEM;
2347
2348 if (add_uevent_var(env, "MODALIAS=hid:b%04Xg%04Xv%08Xp%08X",
2349 hdev->bus, hdev->group, hdev->vendor, hdev->product))
2350 return -ENOMEM;
2351
2352 return 0;
2353 }
2354
2355 struct bus_type hid_bus_type = {
2356 .name = "hid",
2357 .dev_groups = hid_dev_groups,
2358 .drv_groups = hid_drv_groups,
2359 .match = hid_bus_match,
2360 .probe = hid_device_probe,
2361 .remove = hid_device_remove,
2362 .uevent = hid_uevent,
2363 };
2364 EXPORT_SYMBOL(hid_bus_type);
2365
2366 int hid_add_device(struct hid_device *hdev)
2367 {
2368 static atomic_t id = ATOMIC_INIT(0);
2369 int ret;
2370
2371 if (WARN_ON(hdev->status & HID_STAT_ADDED))
2372 return -EBUSY;
2373
2374 hdev->quirks = hid_lookup_quirk(hdev);
2375
2376 /* we need to kill them here, otherwise they will stay allocated to
2377 * wait for coming driver */
2378 if (hid_ignore(hdev))
2379 return -ENODEV;
2380
2381 /*
2382 * Check for the mandatory transport channel.
2383 */
2384 if (!hdev->ll_driver->raw_request) {
2385 hid_err(hdev, "transport driver missing .raw_request()\n");
2386 return -EINVAL;
2387 }
2388
2389 /*
2390 * Read the device report descriptor once and use as template
2391 * for the driver-specific modifications.
2392 */
2393 ret = hdev->ll_driver->parse(hdev);
2394 if (ret)
2395 return ret;
2396 if (!hdev->dev_rdesc)
2397 return -ENODEV;
2398
2399 /*
2400 * Scan generic devices for group information
2401 */
2402 if (hid_ignore_special_drivers) {
2403 hdev->group = HID_GROUP_GENERIC;
2404 } else if (!hdev->group &&
2405 !(hdev->quirks & HID_QUIRK_HAVE_SPECIAL_DRIVER)) {
2406 ret = hid_scan_report(hdev);
2407 if (ret)
2408 hid_warn(hdev, "bad device descriptor (%d)\n", ret);
2409 }
2410
2411 /* XXX hack, any other cleaner solution after the driver core
2412 * is converted to allow more than 20 bytes as the device name? */
2413 dev_set_name(&hdev->dev, "%04X:%04X:%04X.%04X", hdev->bus,
2414 hdev->vendor, hdev->product, atomic_inc_return(&id));
2415
2416 hid_debug_register(hdev, dev_name(&hdev->dev));
2417 ret = device_add(&hdev->dev);
2418 if (!ret)
2419 hdev->status |= HID_STAT_ADDED;
2420 else
2421 hid_debug_unregister(hdev);
2422
2423 return ret;
2424 }
2425 EXPORT_SYMBOL_GPL(hid_add_device);
2426
2427 /**
2428 * hid_allocate_device - allocate new hid device descriptor
2429 *
2430 * Allocate and initialize hid device, so that hid_destroy_device might be
2431 * used to free it.
2432 *
2433 * New hid_device pointer is returned on success, otherwise ERR_PTR encoded
2434 * error value.
2435 */
2436 struct hid_device *hid_allocate_device(void)
2437 {
2438 struct hid_device *hdev;
2439 int ret = -ENOMEM;
2440
2441 hdev = kzalloc(sizeof(*hdev), GFP_KERNEL);
2442 if (hdev == NULL)
2443 return ERR_PTR(ret);
2444
2445 device_initialize(&hdev->dev);
2446 hdev->dev.release = hid_device_release;
2447 hdev->dev.bus = &hid_bus_type;
2448 device_enable_async_suspend(&hdev->dev);
2449
2450 hid_close_report(hdev);
2451
2452 init_waitqueue_head(&hdev->debug_wait);
2453 INIT_LIST_HEAD(&hdev->debug_list);
2454 spin_lock_init(&hdev->debug_list_lock);
2455 sema_init(&hdev->driver_input_lock, 1);
2456 mutex_init(&hdev->ll_open_lock);
2457
2458 return hdev;
2459 }
2460 EXPORT_SYMBOL_GPL(hid_allocate_device);
2461
2462 static void hid_remove_device(struct hid_device *hdev)
2463 {
2464 if (hdev->status & HID_STAT_ADDED) {
2465 device_del(&hdev->dev);
2466 hid_debug_unregister(hdev);
2467 hdev->status &= ~HID_STAT_ADDED;
2468 }
2469 kfree(hdev->dev_rdesc);
2470 hdev->dev_rdesc = NULL;
2471 hdev->dev_rsize = 0;
2472 }
2473
2474 /**
2475 * hid_destroy_device - free previously allocated device
2476 *
2477 * @hdev: hid device
2478 *
2479 * If you allocate hid_device through hid_allocate_device, you should ever
2480 * free by this function.
2481 */
2482 void hid_destroy_device(struct hid_device *hdev)
2483 {
2484 hid_remove_device(hdev);
2485 put_device(&hdev->dev);
2486 }
2487 EXPORT_SYMBOL_GPL(hid_destroy_device);
2488
2489
2490 static int __hid_bus_reprobe_drivers(struct device *dev, void *data)
2491 {
2492 struct hid_driver *hdrv = data;
2493 struct hid_device *hdev = to_hid_device(dev);
2494
2495 if (hdev->driver == hdrv &&
2496 !hdrv->match(hdev, hid_ignore_special_drivers) &&
2497 !test_and_set_bit(ffs(HID_STAT_REPROBED), &hdev->status))
2498 return device_reprobe(dev);
2499
2500 return 0;
2501 }
2502
2503 static int __hid_bus_driver_added(struct device_driver *drv, void *data)
2504 {
2505 struct hid_driver *hdrv = to_hid_driver(drv);
2506
2507 if (hdrv->match) {
2508 bus_for_each_dev(&hid_bus_type, NULL, hdrv,
2509 __hid_bus_reprobe_drivers);
2510 }
2511
2512 return 0;
2513 }
2514
2515 static int __bus_removed_driver(struct device_driver *drv, void *data)
2516 {
2517 return bus_rescan_devices(&hid_bus_type);
2518 }
2519
2520 int __hid_register_driver(struct hid_driver *hdrv, struct module *owner,
2521 const char *mod_name)
2522 {
2523 int ret;
2524
2525 hdrv->driver.name = hdrv->name;
2526 hdrv->driver.bus = &hid_bus_type;
2527 hdrv->driver.owner = owner;
2528 hdrv->driver.mod_name = mod_name;
2529
2530 INIT_LIST_HEAD(&hdrv->dyn_list);
2531 spin_lock_init(&hdrv->dyn_lock);
2532
2533 ret = driver_register(&hdrv->driver);
2534
2535 if (ret == 0)
2536 bus_for_each_drv(&hid_bus_type, NULL, NULL,
2537 __hid_bus_driver_added);
2538
2539 return ret;
2540 }
2541 EXPORT_SYMBOL_GPL(__hid_register_driver);
2542
2543 void hid_unregister_driver(struct hid_driver *hdrv)
2544 {
2545 driver_unregister(&hdrv->driver);
2546 hid_free_dynids(hdrv);
2547
2548 bus_for_each_drv(&hid_bus_type, NULL, hdrv, __bus_removed_driver);
2549 }
2550 EXPORT_SYMBOL_GPL(hid_unregister_driver);
2551
2552 int hid_check_keys_pressed(struct hid_device *hid)
2553 {
2554 struct hid_input *hidinput;
2555 int i;
2556
2557 if (!(hid->claimed & HID_CLAIMED_INPUT))
2558 return 0;
2559
2560 list_for_each_entry(hidinput, &hid->inputs, list) {
2561 for (i = 0; i < BITS_TO_LONGS(KEY_MAX); i++)
2562 if (hidinput->input->key[i])
2563 return 1;
2564 }
2565
2566 return 0;
2567 }
2568
2569 EXPORT_SYMBOL_GPL(hid_check_keys_pressed);
2570
2571 static int __init hid_init(void)
2572 {
2573 int ret;
2574
2575 if (hid_debug)
2576 pr_warn("hid_debug is now used solely for parser and driver debugging.\n"
2577 "debugfs is now used for inspecting the device (report descriptor, reports)\n");
2578
2579 ret = bus_register(&hid_bus_type);
2580 if (ret) {
2581 pr_err("can't register hid bus\n");
2582 goto err;
2583 }
2584
2585 ret = hidraw_init();
2586 if (ret)
2587 goto err_bus;
2588
2589 hid_debug_init();
2590
2591 return 0;
2592 err_bus:
2593 bus_unregister(&hid_bus_type);
2594 err:
2595 return ret;
2596 }
2597
2598 static void __exit hid_exit(void)
2599 {
2600 hid_debug_exit();
2601 hidraw_exit();
2602 bus_unregister(&hid_bus_type);
2603 hid_quirks_exit(HID_BUS_ANY);
2604 }
2605
2606 module_init(hid_init);
2607 module_exit(hid_exit);
2608
2609 MODULE_AUTHOR("Andreas Gal");
2610 MODULE_AUTHOR("Vojtech Pavlik");
2611 MODULE_AUTHOR("Jiri Kosina");
2612 MODULE_LICENSE("GPL");
Linux with added FPC-III support