summaryrefslogtreecommitdiff
path: root/include/media/v4l2-mem2mem.h
blob: 98753f00df7e88a8aca0db913677604463743ae2 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
 * Memory-to-memory device framework for Video for Linux 2.
 *
 * Helper functions for devices that use memory buffers for both source
 * and destination.
 *
 * Copyright (c) 2009 Samsung Electronics Co., Ltd.
 * Pawel Osciak, <pawel@osciak.com>
 * Marek Szyprowski, <m.szyprowski@samsung.com>
 */

#ifndef _MEDIA_V4L2_MEM2MEM_H
#define _MEDIA_V4L2_MEM2MEM_H

#include <media/videobuf2-v4l2.h>

/**
 * struct v4l2_m2m_ops - mem-to-mem device driver callbacks
 * @device_run:	required. Begin the actual job (transaction) inside this
 *		callback.
 *		The job does NOT have to end before this callback returns
 *		(and it will be the usual case). When the job finishes,
 *		v4l2_m2m_job_finish() or v4l2_m2m_buf_done_and_job_finish()
 *		has to be called.
 * @job_ready:	optional. Should return 0 if the driver does not have a job
 *		fully prepared to run yet (i.e. it will not be able to finish a
 *		transaction without sleeping). If not provided, it will be
 *		assumed that one source and one destination buffer are all
 *		that is required for the driver to perform one full transaction.
 *		This method may not sleep.
 * @job_abort:	optional. Informs the driver that it has to abort the currently
 *		running transaction as soon as possible (i.e. as soon as it can
 *		stop the device safely; e.g. in the next interrupt handler),
 *		even if the transaction would not have been finished by then.
 *		After the driver performs the necessary steps, it has to call
 *		v4l2_m2m_job_finish() or v4l2_m2m_buf_done_and_job_finish() as
 *		if the transaction ended normally.
 *		This function does not have to (and will usually not) wait
 *		until the device enters a state when it can be stopped.
 */
struct v4l2_m2m_ops {
	void (*device_run)(void *priv);
	int (*job_ready)(void *priv);
	void (*job_abort)(void *priv);
};

struct video_device;
struct v4l2_m2m_dev;

/**
 * struct v4l2_m2m_queue_ctx - represents a queue for buffers ready to be
 *	processed
 *
 * @q:		pointer to struct &vb2_queue
 * @rdy_queue:	List of V4L2 mem-to-mem queues
 * @rdy_spinlock: spin lock to protect the struct usage
 * @num_rdy:	number of buffers ready to be processed
 * @buffered:	is the queue buffered?
 *
 * Queue for buffers ready to be processed as soon as this
 * instance receives access to the device.
 */

struct v4l2_m2m_queue_ctx {
	struct vb2_queue	q;

	struct list_head	rdy_queue;
	spinlock_t		rdy_spinlock;
	u8			num_rdy;
	bool			buffered;
};

/**
 * struct v4l2_m2m_ctx - Memory to memory context structure
 *
 * @q_lock: struct &mutex lock
 * @new_frame: valid in the device_run callback: if true, then this
 *		starts a new frame; if false, then this is a new slice
 *		for an existing frame. This is always true unless
 *		V4L2_BUF_CAP_SUPPORTS_M2M_HOLD_CAPTURE_BUF is set, which
 *		indicates slicing support.
 * @is_draining: indicates device is in draining phase
 * @last_src_buf: indicate the last source buffer for draining
 * @next_buf_last: next capture queud buffer will be tagged as last
 * @has_stopped: indicate the device has been stopped
 * @m2m_dev: opaque pointer to the internal data to handle M2M context
 * @cap_q_ctx: Capture (output to memory) queue context
 * @out_q_ctx: Output (input from memory) queue context
 * @queue: List of memory to memory contexts
 * @job_flags: Job queue flags, used internally by v4l2-mem2mem.c:
 *		%TRANS_QUEUED, %TRANS_RUNNING and %TRANS_ABORT.
 * @finished: Wait queue used to signalize when a job queue finished.
 * @priv: Instance private data
 *
 * The memory to memory context is specific to a file handle, NOT to e.g.
 * a device.
 */
struct v4l2_m2m_ctx {
	/* optional cap/out vb2 queues lock */
	struct mutex			*q_lock;

	bool				new_frame;

	bool				is_draining;
	struct vb2_v4l2_buffer		*last_src_buf;
	bool				next_buf_last;
	bool				has_stopped;

	/* internal use only */
	struct v4l2_m2m_dev		*m2m_dev;

	struct v4l2_m2m_queue_ctx	cap_q_ctx;

	struct v4l2_m2m_queue_ctx	out_q_ctx;

	/* For device job queue */
	struct list_head		queue;
	unsigned long			job_flags;
	wait_queue_head_t		finished;

	void				*priv;
};

/**
 * struct v4l2_m2m_buffer - Memory to memory buffer
 *
 * @vb: pointer to struct &vb2_v4l2_buffer
 * @list: list of m2m buffers
 */
struct v4l2_m2m_buffer {
	struct vb2_v4l2_buffer	vb;
	struct list_head	list;
};

/**
 * v4l2_m2m_get_curr_priv() - return driver private data for the currently
 * running instance or NULL if no instance is running
 *
 * @m2m_dev: opaque pointer to the internal data to handle M2M context
 */
void *v4l2_m2m_get_curr_priv(struct v4l2_m2m_dev *m2m_dev);

/**
 * v4l2_m2m_get_vq() - return vb2_queue for the given type
 *
 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
 * @type: type of the V4L2 buffer, as defined by enum &v4l2_buf_type
 */
struct vb2_queue *v4l2_m2m_get_vq(struct v4l2_m2m_ctx *m2m_ctx,
				       enum v4l2_buf_type type);

/**
 * v4l2_m2m_try_schedule() - check whether an instance is ready to be added to
 * the pending job queue and add it if so.
 *
 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
 *
 * There are three basic requirements an instance has to meet to be able to run:
 * 1) at least one source buffer has to be queued,
 * 2) at least one destination buffer has to be queued,
 * 3) streaming has to be on.
 *
 * If a queue is buffered (for example a decoder hardware ringbuffer that has
 * to be drained before doing streamoff), allow scheduling without v4l2 buffers
 * on that queue.
 *
 * There may also be additional, custom requirements. In such case the driver
 * should supply a custom callback (job_ready in v4l2_m2m_ops) that should
 * return 1 if the instance is ready.
 * An example of the above could be an instance that requires more than one
 * src/dst buffer per transaction.
 */
void v4l2_m2m_try_schedule(struct v4l2_m2m_ctx *m2m_ctx);

/**
 * v4l2_m2m_job_finish() - inform the framework that a job has been finished
 * and have it clean up
 *
 * @m2m_dev: opaque pointer to the internal data to handle M2M context
 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
 *
 * Called by a driver to yield back the device after it has finished with it.
 * Should be called as soon as possible after reaching a state which allows
 * other instances to take control of the device.
 *
 * This function has to be called only after &v4l2_m2m_ops->device_run
 * callback has been called on the driver. To prevent recursion, it should
 * not be called directly from the &v4l2_m2m_ops->device_run callback though.
 */
void v4l2_m2m_job_finish(struct v4l2_m2m_dev *m2m_dev,
			 struct v4l2_m2m_ctx *m2m_ctx);

/**
 * v4l2_m2m_buf_done_and_job_finish() - return source/destination buffers with
 * state and inform the framework that a job has been finished and have it
 * clean up
 *
 * @m2m_dev: opaque pointer to the internal data to handle M2M context
 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
 * @state: vb2 buffer state passed to v4l2_m2m_buf_done().
 *
 * Drivers that set V4L2_BUF_CAP_SUPPORTS_M2M_HOLD_CAPTURE_BUF must use this
 * function instead of job_finish() to take held buffers into account. It is
 * optional for other drivers.
 *
 * This function removes the source buffer from the ready list and returns
 * it with the given state. The same is done for the destination buffer, unless
 * it is marked 'held'. In that case the buffer is kept on the ready list.
 *
 * After that the job is finished (see job_finish()).
 *
 * This allows for multiple output buffers to be used to fill in a single
 * capture buffer. This is typically used by stateless decoders where
 * multiple e.g. H.264 slices contribute to a single decoded frame.
 */
void v4l2_m2m_buf_done_and_job_finish(struct v4l2_m2m_dev *m2m_dev,
				      struct v4l2_m2m_ctx *m2m_ctx,
				      enum vb2_buffer_state state);

static inline void
v4l2_m2m_buf_done(struct vb2_v4l2_buffer *buf, enum vb2_buffer_state state)
{
	vb2_buffer_done(&buf->vb2_buf, state);
}

/**
 * v4l2_m2m_clear_state() - clear encoding/decoding state
 *
 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
 */
static inline void
v4l2_m2m_clear_state(struct v4l2_m2m_ctx *m2m_ctx)
{
	m2m_ctx->next_buf_last = false;
	m2m_ctx->is_draining = false;
	m2m_ctx->has_stopped = false;
}

/**
 * v4l2_m2m_mark_stopped() - set current encoding/decoding state as stopped
 *
 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
 */
static inline void
v4l2_m2m_mark_stopped(struct v4l2_m2m_ctx *m2m_ctx)
{
	m2m_ctx->next_buf_last = false;
	m2m_ctx->is_draining = false;
	m2m_ctx->has_stopped = true;
}

/**
 * v4l2_m2m_dst_buf_is_last() - return the current encoding/decoding session
 * draining management state of next queued capture buffer
 *
 * This last capture buffer should be tagged with V4L2_BUF_FLAG_LAST to notify
 * the end of the capture session.
 *
 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
 */
static inline bool
v4l2_m2m_dst_buf_is_last(struct v4l2_m2m_ctx *m2m_ctx)
{
	return m2m_ctx->is_draining && m2m_ctx->next_buf_last;
}

/**
 * v4l2_m2m_has_stopped() - return the current encoding/decoding session
 * stopped state
 *
 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
 */
static inline bool
v4l2_m2m_has_stopped(struct v4l2_m2m_ctx *m2m_ctx)
{
	return m2m_ctx->has_stopped;
}

/**
 * v4l2_m2m_is_last_draining_src_buf() - return the output buffer draining
 * state in the current encoding/decoding session
 *
 * This will identify the last output buffer queued before a session stop
 * was required, leading to an actual encoding/decoding session stop state
 * in the encoding/decoding process after being processed.
 *
 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
 * @vbuf: pointer to struct &v4l2_buffer
 */
static inline bool
v4l2_m2m_is_last_draining_src_buf(struct v4l2_m2m_ctx *m2m_ctx,
				  struct vb2_v4l2_buffer *vbuf)
{
	return m2m_ctx->is_draining && vbuf == m2m_ctx->last_src_buf;
}

/**
 * v4l2_m2m_last_buffer_done() - marks the buffer with LAST flag and DONE
 *
 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
 * @vbuf: pointer to struct &v4l2_buffer
 */
void v4l2_m2m_last_buffer_done(struct v4l2_m2m_ctx *m2m_ctx,
			       struct vb2_v4l2_buffer *vbuf);

/**
 * v4l2_m2m_reqbufs() - multi-queue-aware REQBUFS multiplexer
 *
 * @file: pointer to struct &file
 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
 * @reqbufs: pointer to struct &v4l2_requestbuffers
 */
int v4l2_m2m_reqbufs(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
		     struct v4l2_requestbuffers *reqbufs);

/**
 * v4l2_m2m_querybuf() - multi-queue-aware QUERYBUF multiplexer
 *
 * @file: pointer to struct &file
 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
 * @buf: pointer to struct &v4l2_buffer
 *
 * See v4l2_m2m_mmap() documentation for details.
 */
int v4l2_m2m_querybuf(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
		      struct v4l2_buffer *buf);

/**
 * v4l2_m2m_qbuf() - enqueue a source or destination buffer, depending on
 * the type
 *
 * @file: pointer to struct &file
 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
 * @buf: pointer to struct &v4l2_buffer
 */
int v4l2_m2m_qbuf(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
		  struct v4l2_buffer *buf);

/**
 * v4l2_m2m_dqbuf() - dequeue a source or destination buffer, depending on
 * the type
 *
 * @file: pointer to struct &file
 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
 * @buf: pointer to struct &v4l2_buffer
 */
int v4l2_m2m_dqbuf(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
		   struct v4l2_buffer *buf);

/**
 * v4l2_m2m_prepare_buf() - prepare a source or destination buffer, depending on
 * the type
 *
 * @file: pointer to struct &file
 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
 * @buf: pointer to struct &v4l2_buffer
 */
int v4l2_m2m_prepare_buf(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
			 struct v4l2_buffer *buf);

/**
 * v4l2_m2m_create_bufs() - create a source or destination buffer, depending
 * on the type
 *
 * @file: pointer to struct &file
 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
 * @create: pointer to struct &v4l2_create_buffers
 */
int v4l2_m2m_create_bufs(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
			 struct v4l2_create_buffers *create);

/**
 * v4l2_m2m_expbuf() - export a source or destination buffer, depending on
 * the type
 *
 * @file: pointer to struct &file
 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
 * @eb: pointer to struct &v4l2_exportbuffer
 */
int v4l2_m2m_expbuf(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
		   struct v4l2_exportbuffer *eb);

/**
 * v4l2_m2m_streamon() - turn on streaming for a video queue
 *
 * @file: pointer to struct &file
 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
 * @type: type of the V4L2 buffer, as defined by enum &v4l2_buf_type
 */
int v4l2_m2m_streamon(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
		      enum v4l2_buf_type type);

/**
 * v4l2_m2m_streamoff() - turn off streaming for a video queue
 *
 * @file: pointer to struct &file
 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
 * @type: type of the V4L2 buffer, as defined by enum &v4l2_buf_type
 */
int v4l2_m2m_streamoff(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
		       enum v4l2_buf_type type);

/**
 * v4l2_m2m_update_start_streaming_state() - update the encoding/decoding
 * session state when a start of streaming of a video queue is requested
 *
 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
 * @q: queue
 */
void v4l2_m2m_update_start_streaming_state(struct v4l2_m2m_ctx *m2m_ctx,
					   struct vb2_queue *q);

/**
 * v4l2_m2m_update_stop_streaming_state() -  update the encoding/decoding
 * session state when a stop of streaming of a video queue is requested
 *
 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
 * @q: queue
 */
void v4l2_m2m_update_stop_streaming_state(struct v4l2_m2m_ctx *m2m_ctx,
					  struct vb2_queue *q);

/**
 * v4l2_m2m_encoder_cmd() - execute an encoder command
 *
 * @file: pointer to struct &file
 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
 * @ec: pointer to the encoder command
 */
int v4l2_m2m_encoder_cmd(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
			 struct v4l2_encoder_cmd *ec);

/**
 * v4l2_m2m_decoder_cmd() - execute a decoder command
 *
 * @file: pointer to struct &file
 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
 * @dc: pointer to the decoder command
 */
int v4l2_m2m_decoder_cmd(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
			 struct v4l2_decoder_cmd *dc);

/**
 * v4l2_m2m_poll() - poll replacement, for destination buffers only
 *
 * @file: pointer to struct &file
 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
 * @wait: pointer to struct &poll_table_struct
 *
 * Call from the driver's poll() function. Will poll both queues. If a buffer
 * is available to dequeue (with dqbuf) from the source queue, this will
 * indicate that a non-blocking write can be performed, while read will be
 * returned in case of the destination queue.
 */
__poll_t v4l2_m2m_poll(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
			   struct poll_table_struct *wait);

/**
 * v4l2_m2m_mmap() - source and destination queues-aware mmap multiplexer
 *
 * @file: pointer to struct &file
 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
 * @vma: pointer to struct &vm_area_struct
 *
 * Call from driver's mmap() function. Will handle mmap() for both queues
 * seamlessly for videobuffer, which will receive normal per-queue offsets and
 * proper videobuf queue pointers. The differentiation is made outside videobuf
 * by adding a predefined offset to buffers from one of the queues and
 * subtracting it before passing it back to videobuf. Only drivers (and
 * thus applications) receive modified offsets.
 */
int v4l2_m2m_mmap(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
		  struct vm_area_struct *vma);

/**
 * v4l2_m2m_init() - initialize per-driver m2m data
 *
 * @m2m_ops: pointer to struct v4l2_m2m_ops
 *
 * Usually called from driver's ``probe()`` function.
 *
 * Return: returns an opaque pointer to the internal data to handle M2M context
 */
struct v4l2_m2m_dev *v4l2_m2m_init(const struct v4l2_m2m_ops *m2m_ops);

#if defined(CONFIG_MEDIA_CONTROLLER)
void v4l2_m2m_unregister_media_controller(struct v4l2_m2m_dev *m2m_dev);
int v4l2_m2m_register_media_controller(struct v4l2_m2m_dev *m2m_dev,
			struct video_device *vdev, int function);
#else
static inline void
v4l2_m2m_unregister_media_controller(struct v4l2_m2m_dev *m2m_dev)
{
}

static inline int
v4l2_m2m_register_media_controller(struct v4l2_m2m_dev *m2m_dev,
		struct video_device *vdev, int function)
{
	return 0;
}
#endif

/**
 * v4l2_m2m_release() - cleans up and frees a m2m_dev structure
 *
 * @m2m_dev: opaque pointer to the internal data to handle M2M context
 *
 * Usually called from driver's ``remove()`` function.
 */
void v4l2_m2m_release(struct v4l2_m2m_dev *m2m_dev);

/**
 * v4l2_m2m_ctx_init() - allocate and initialize a m2m context
 *
 * @m2m_dev: opaque pointer to the internal data to handle M2M context
 * @drv_priv: driver's instance private data
 * @queue_init: a callback for queue type-specific initialization function
 *	to be used for initializing videobuf_queues
 *
 * Usually called from driver's ``open()`` function.
 */
struct v4l2_m2m_ctx *v4l2_m2m_ctx_init(struct v4l2_m2m_dev *m2m_dev,
		void *drv_priv,
		int (*queue_init)(void *priv, struct vb2_queue *src_vq, struct vb2_queue *dst_vq));

static inline void v4l2_m2m_set_src_buffered(struct v4l2_m2m_ctx *m2m_ctx,
					     bool buffered)
{
	m2m_ctx->out_q_ctx.buffered = buffered;
}

static inline void v4l2_m2m_set_dst_buffered(struct v4l2_m2m_ctx *m2m_ctx,
					     bool buffered)
{
	m2m_ctx->cap_q_ctx.buffered = buffered;
}

/**
 * v4l2_m2m_ctx_release() - release m2m context
 *
 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
 *
 * Usually called from driver's release() function.
 */
void v4l2_m2m_ctx_release(struct v4l2_m2m_ctx *m2m_ctx);

/**
 * v4l2_m2m_buf_queue() - add a buffer to the proper ready buffers list.
 *
 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
 * @vbuf: pointer to struct &vb2_v4l2_buffer
 *
 * Call from videobuf_queue_ops->ops->buf_queue, videobuf_queue_ops callback.
 */
void v4l2_m2m_buf_queue(struct v4l2_m2m_ctx *m2m_ctx,
			struct vb2_v4l2_buffer *vbuf);

/**
 * v4l2_m2m_num_src_bufs_ready() - return the number of source buffers ready for
 * use
 *
 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
 */
static inline
unsigned int v4l2_m2m_num_src_bufs_ready(struct v4l2_m2m_ctx *m2m_ctx)
{
	return m2m_ctx->out_q_ctx.num_rdy;
}

/**
 * v4l2_m2m_num_dst_bufs_ready() - return the number of destination buffers
 * ready for use
 *
 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
 */
static inline
unsigned int v4l2_m2m_num_dst_bufs_ready(struct v4l2_m2m_ctx *m2m_ctx)
{
	return m2m_ctx->cap_q_ctx.num_rdy;
}

/**
 * v4l2_m2m_next_buf() - return next buffer from the list of ready buffers
 *
 * @q_ctx: pointer to struct @v4l2_m2m_queue_ctx
 */
struct vb2_v4l2_buffer *v4l2_m2m_next_buf(struct v4l2_m2m_queue_ctx *q_ctx);

/**
 * v4l2_m2m_next_src_buf() - return next source buffer from the list of ready
 * buffers
 *
 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
 */
static inline struct vb2_v4l2_buffer *
v4l2_m2m_next_src_buf(struct v4l2_m2m_ctx *m2m_ctx)
{
	return v4l2_m2m_next_buf(&m2m_ctx->out_q_ctx);
}

/**
 * v4l2_m2m_next_dst_buf() - return next destination buffer from the list of
 * ready buffers
 *
 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
 */
static inline struct vb2_v4l2_buffer *
v4l2_m2m_next_dst_buf(struct v4l2_m2m_ctx *m2m_ctx)
{
	return v4l2_m2m_next_buf(&m2m_ctx->cap_q_ctx);
}

/**
 * v4l2_m2m_last_buf() - return last buffer from the list of ready buffers
 *
 * @q_ctx: pointer to struct @v4l2_m2m_queue_ctx
 */
struct vb2_v4l2_buffer *v4l2_m2m_last_buf(struct v4l2_m2m_queue_ctx *q_ctx);

/**
 * v4l2_m2m_last_src_buf() - return last destination buffer from the list of
 * ready buffers
 *
 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
 */
static inline struct vb2_v4l2_buffer *
v4l2_m2m_last_src_buf(struct v4l2_m2m_ctx *m2m_ctx)
{
	return v4l2_m2m_last_buf(&m2m_ctx->out_q_ctx);
}

/**
 * v4l2_m2m_last_dst_buf() - return last destination buffer from the list of
 * ready buffers
 *
 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
 */
static inline struct vb2_v4l2_buffer *
v4l2_m2m_last_dst_buf(struct v4l2_m2m_ctx *m2m_ctx)
{
	return v4l2_m2m_last_buf(&m2m_ctx->cap_q_ctx);
}

/**
 * v4l2_m2m_for_each_dst_buf() - iterate over a list of destination ready
 * buffers
 *
 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
 * @b: current buffer of type struct v4l2_m2m_buffer
 */
#define v4l2_m2m_for_each_dst_buf(m2m_ctx, b)	\
	list_for_each_entry(b, &m2m_ctx->cap_q_ctx.rdy_queue, list)

/**
 * v4l2_m2m_for_each_src_buf() - iterate over a list of source ready buffers
 *
 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
 * @b: current buffer of type struct v4l2_m2m_buffer
 */
#define v4l2_m2m_for_each_src_buf(m2m_ctx, b)	\
	list_for_each_entry(b, &m2m_ctx->out_q_ctx.rdy_queue, list)

/**
 * v4l2_m2m_for_each_dst_buf_safe() - iterate over a list of destination ready
 * buffers safely
 *
 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
 * @b: current buffer of type struct v4l2_m2m_buffer
 * @n: used as temporary storage
 */
#define v4l2_m2m_for_each_dst_buf_safe(m2m_ctx, b, n)	\
	list_for_each_entry_safe(b, n, &m2m_ctx->cap_q_ctx.rdy_queue, list)

/**
 * v4l2_m2m_for_each_src_buf_safe() - iterate over a list of source ready
 * buffers safely
 *
 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
 * @b: current buffer of type struct v4l2_m2m_buffer
 * @n: used as temporary storage
 */
#define v4l2_m2m_for_each_src_buf_safe(m2m_ctx, b, n)	\
	list_for_each_entry_safe(b, n, &m2m_ctx->out_q_ctx.rdy_queue, list)

/**
 * v4l2_m2m_get_src_vq() - return vb2_queue for source buffers
 *
 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
 */
static inline
struct vb2_queue *v4l2_m2m_get_src_vq(struct v4l2_m2m_ctx *m2m_ctx)
{
	return &m2m_ctx->out_q_ctx.q;
}

/**
 * v4l2_m2m_get_dst_vq() - return vb2_queue for destination buffers
 *
 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
 */
static inline
struct vb2_queue *v4l2_m2m_get_dst_vq(struct v4l2_m2m_ctx *m2m_ctx)
{
	return &m2m_ctx->cap_q_ctx.q;
}

/**
 * v4l2_m2m_buf_remove() - take off a buffer from the list of ready buffers and
 * return it
 *
 * @q_ctx: pointer to struct @v4l2_m2m_queue_ctx
 */
struct vb2_v4l2_buffer *v4l2_m2m_buf_remove(struct v4l2_m2m_queue_ctx *q_ctx);

/**
 * v4l2_m2m_src_buf_remove() - take off a source buffer from the list of ready
 * buffers and return it
 *
 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
 */
static inline struct vb2_v4l2_buffer *
v4l2_m2m_src_buf_remove(struct v4l2_m2m_ctx *m2m_ctx)
{
	return v4l2_m2m_buf_remove(&m2m_ctx->out_q_ctx);
}

/**
 * v4l2_m2m_dst_buf_remove() - take off a destination buffer from the list of
 * ready buffers and return it
 *
 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
 */
static inline struct vb2_v4l2_buffer *
v4l2_m2m_dst_buf_remove(struct v4l2_m2m_ctx *m2m_ctx)
{
	return v4l2_m2m_buf_remove(&m2m_ctx->cap_q_ctx);
}

/**
 * v4l2_m2m_buf_remove_by_buf() - take off exact buffer from the list of ready
 * buffers
 *
 * @q_ctx: pointer to struct @v4l2_m2m_queue_ctx
 * @vbuf: the buffer to be removed
 */
void v4l2_m2m_buf_remove_by_buf(struct v4l2_m2m_queue_ctx *q_ctx,
				struct vb2_v4l2_buffer *vbuf);

/**
 * v4l2_m2m_src_buf_remove_by_buf() - take off exact source buffer from the list
 * of ready buffers
 *
 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
 * @vbuf: the buffer to be removed
 */
static inline void v4l2_m2m_src_buf_remove_by_buf(struct v4l2_m2m_ctx *m2m_ctx,
						  struct vb2_v4l2_buffer *vbuf)
{
	v4l2_m2m_buf_remove_by_buf(&m2m_ctx->out_q_ctx, vbuf);
}

/**
 * v4l2_m2m_dst_buf_remove_by_buf() - take off exact destination buffer from the
 * list of ready buffers
 *
 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
 * @vbuf: the buffer to be removed
 */
static inline void v4l2_m2m_dst_buf_remove_by_buf(struct v4l2_m2m_ctx *m2m_ctx,
						  struct vb2_v4l2_buffer *vbuf)
{
	v4l2_m2m_buf_remove_by_buf(&m2m_ctx->cap_q_ctx, vbuf);
}

struct vb2_v4l2_buffer *
v4l2_m2m_buf_remove_by_idx(struct v4l2_m2m_queue_ctx *q_ctx, unsigned int idx);

static inline struct vb2_v4l2_buffer *
v4l2_m2m_src_buf_remove_by_idx(struct v4l2_m2m_ctx *m2m_ctx, unsigned int idx)
{
	return v4l2_m2m_buf_remove_by_idx(&m2m_ctx->out_q_ctx, idx);
}

static inline struct vb2_v4l2_buffer *
v4l2_m2m_dst_buf_remove_by_idx(struct v4l2_m2m_ctx *m2m_ctx, unsigned int idx)
{
	return v4l2_m2m_buf_remove_by_idx(&m2m_ctx->cap_q_ctx, idx);
}

/**
 * v4l2_m2m_buf_copy_metadata() - copy buffer metadata from
 * the output buffer to the capture buffer
 *
 * @out_vb: the output buffer that is the source of the metadata.
 * @cap_vb: the capture buffer that will receive the metadata.
 * @copy_frame_flags: copy the KEY/B/PFRAME flags as well.
 *
 * This helper function copies the timestamp, timecode (if the TIMECODE
 * buffer flag was set), field and the TIMECODE, KEYFRAME, BFRAME, PFRAME
 * and TSTAMP_SRC_MASK flags from @out_vb to @cap_vb.
 *
 * If @copy_frame_flags is false, then the KEYFRAME, BFRAME and PFRAME
 * flags are not copied. This is typically needed for encoders that
 * set this bits explicitly.
 */
void v4l2_m2m_buf_copy_metadata(const struct vb2_v4l2_buffer *out_vb,
				struct vb2_v4l2_buffer *cap_vb,
				bool copy_frame_flags);

/* v4l2 request helper */

void v4l2_m2m_request_queue(struct media_request *req);

/* v4l2 ioctl helpers */

int v4l2_m2m_ioctl_reqbufs(struct file *file, void *priv,
				struct v4l2_requestbuffers *rb);
int v4l2_m2m_ioctl_create_bufs(struct file *file, void *fh,
				struct v4l2_create_buffers *create);
int v4l2_m2m_ioctl_querybuf(struct file *file, void *fh,
				struct v4l2_buffer *buf);
int v4l2_m2m_ioctl_expbuf(struct file *file, void *fh,
				struct v4l2_exportbuffer *eb);
int v4l2_m2m_ioctl_qbuf(struct file *file, void *fh,
				struct v4l2_buffer *buf);
int v4l2_m2m_ioctl_dqbuf(struct file *file, void *fh,
				struct v4l2_buffer *buf);
int v4l2_m2m_ioctl_prepare_buf(struct file *file, void *fh,
			       struct v4l2_buffer *buf);
int v4l2_m2m_ioctl_streamon(struct file *file, void *fh,
				enum v4l2_buf_type type);
int v4l2_m2m_ioctl_streamoff(struct file *file, void *fh,
				enum v4l2_buf_type type);
int v4l2_m2m_ioctl_encoder_cmd(struct file *file, void *fh,
			       struct v4l2_encoder_cmd *ec);
int v4l2_m2m_ioctl_decoder_cmd(struct file *file, void *fh,
			       struct v4l2_decoder_cmd *dc);
int v4l2_m2m_ioctl_try_encoder_cmd(struct file *file, void *fh,
				   struct v4l2_encoder_cmd *ec);
int v4l2_m2m_ioctl_try_decoder_cmd(struct file *file, void *fh,
				   struct v4l2_decoder_cmd *dc);
int v4l2_m2m_ioctl_stateless_try_decoder_cmd(struct file *file, void *fh,
					     struct v4l2_decoder_cmd *dc);
int v4l2_m2m_ioctl_stateless_decoder_cmd(struct file *file, void *priv,
					 struct v4l2_decoder_cmd *dc);
int v4l2_m2m_fop_mmap(struct file *file, struct vm_area_struct *vma);
__poll_t v4l2_m2m_fop_poll(struct file *file, poll_table *wait);

#endif /* _MEDIA_V4L2_MEM2MEM_H */