xref: /linux/drivers/media/v4l2-core/v4l2-mem2mem.c (revision 151ebcf0797b1a3ba53c8843dc21748c80e098c7)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Memory-to-memory device framework for Video for Linux 2 and vb2.
4  *
5  * Helper functions for devices that use vb2 buffers for both their
6  * source and destination.
7  *
8  * Copyright (c) 2009-2010 Samsung Electronics Co., Ltd.
9  * Pawel Osciak, <pawel@osciak.com>
10  * Marek Szyprowski, <m.szyprowski@samsung.com>
11  */
12 #include <linux/module.h>
13 #include <linux/sched.h>
14 #include <linux/slab.h>
15 
16 #include <media/media-device.h>
17 #include <media/videobuf2-v4l2.h>
18 #include <media/v4l2-mem2mem.h>
19 #include <media/v4l2-dev.h>
20 #include <media/v4l2-device.h>
21 #include <media/v4l2-fh.h>
22 #include <media/v4l2-event.h>
23 
24 MODULE_DESCRIPTION("Mem to mem device framework for vb2");
25 MODULE_AUTHOR("Pawel Osciak, <pawel@osciak.com>");
26 MODULE_LICENSE("GPL");
27 
28 static bool debug;
29 module_param(debug, bool, 0644);
30 
31 #define dprintk(fmt, arg...)						\
32 	do {								\
33 		if (debug)						\
34 			printk(KERN_DEBUG "%s: " fmt, __func__, ## arg);\
35 	} while (0)
36 
37 
38 /* Instance is already queued on the job_queue */
39 #define TRANS_QUEUED		(1 << 0)
40 /* Instance is currently running in hardware */
41 #define TRANS_RUNNING		(1 << 1)
42 /* Instance is currently aborting */
43 #define TRANS_ABORT		(1 << 2)
44 
45 
46 /* The job queue is not running new jobs */
47 #define QUEUE_PAUSED		(1 << 0)
48 
49 
50 /* Offset base for buffers on the destination queue - used to distinguish
51  * between source and destination buffers when mmapping - they receive the same
52  * offsets but for different queues */
53 #define DST_QUEUE_OFF_BASE	(1 << 30)
54 
55 enum v4l2_m2m_entity_type {
56 	MEM2MEM_ENT_TYPE_SOURCE,
57 	MEM2MEM_ENT_TYPE_SINK,
58 	MEM2MEM_ENT_TYPE_PROC
59 };
60 
61 static const char * const m2m_entity_name[] = {
62 	"source",
63 	"sink",
64 	"proc"
65 };
66 
67 /**
68  * struct v4l2_m2m_dev - per-device context
69  * @source:		&struct media_entity pointer with the source entity
70  *			Used only when the M2M device is registered via
71  *			v4l2_m2m_register_media_controller().
72  * @source_pad:		&struct media_pad with the source pad.
73  *			Used only when the M2M device is registered via
74  *			v4l2_m2m_register_media_controller().
75  * @sink:		&struct media_entity pointer with the sink entity
76  *			Used only when the M2M device is registered via
77  *			v4l2_m2m_register_media_controller().
78  * @sink_pad:		&struct media_pad with the sink pad.
79  *			Used only when the M2M device is registered via
80  *			v4l2_m2m_register_media_controller().
81  * @proc:		&struct media_entity pointer with the M2M device itself.
82  * @proc_pads:		&struct media_pad with the @proc pads.
83  *			Used only when the M2M device is registered via
84  *			v4l2_m2m_unregister_media_controller().
85  * @intf_devnode:	&struct media_intf devnode pointer with the interface
86  *			with controls the M2M device.
87  * @curr_ctx:		currently running instance
88  * @job_queue:		instances queued to run
89  * @job_spinlock:	protects job_queue
90  * @job_work:		worker to run queued jobs.
91  * @job_queue_flags:	flags of the queue status, %QUEUE_PAUSED.
92  * @m2m_ops:		driver callbacks
93  */
94 struct v4l2_m2m_dev {
95 	struct v4l2_m2m_ctx	*curr_ctx;
96 #ifdef CONFIG_MEDIA_CONTROLLER
97 	struct media_entity	*source;
98 	struct media_pad	source_pad;
99 	struct media_entity	sink;
100 	struct media_pad	sink_pad;
101 	struct media_entity	proc;
102 	struct media_pad	proc_pads[2];
103 	struct media_intf_devnode *intf_devnode;
104 #endif
105 
106 	struct list_head	job_queue;
107 	spinlock_t		job_spinlock;
108 	struct work_struct	job_work;
109 	unsigned long		job_queue_flags;
110 
111 	const struct v4l2_m2m_ops *m2m_ops;
112 };
113 
114 static struct v4l2_m2m_queue_ctx *get_queue_ctx(struct v4l2_m2m_ctx *m2m_ctx,
115 						enum v4l2_buf_type type)
116 {
117 	if (V4L2_TYPE_IS_OUTPUT(type))
118 		return &m2m_ctx->out_q_ctx;
119 	else
120 		return &m2m_ctx->cap_q_ctx;
121 }
122 
123 struct vb2_queue *v4l2_m2m_get_vq(struct v4l2_m2m_ctx *m2m_ctx,
124 				       enum v4l2_buf_type type)
125 {
126 	struct v4l2_m2m_queue_ctx *q_ctx;
127 
128 	q_ctx = get_queue_ctx(m2m_ctx, type);
129 	if (!q_ctx)
130 		return NULL;
131 
132 	return &q_ctx->q;
133 }
134 EXPORT_SYMBOL(v4l2_m2m_get_vq);
135 
136 struct vb2_v4l2_buffer *v4l2_m2m_next_buf(struct v4l2_m2m_queue_ctx *q_ctx)
137 {
138 	struct v4l2_m2m_buffer *b;
139 	unsigned long flags;
140 
141 	spin_lock_irqsave(&q_ctx->rdy_spinlock, flags);
142 
143 	if (list_empty(&q_ctx->rdy_queue)) {
144 		spin_unlock_irqrestore(&q_ctx->rdy_spinlock, flags);
145 		return NULL;
146 	}
147 
148 	b = list_first_entry(&q_ctx->rdy_queue, struct v4l2_m2m_buffer, list);
149 	spin_unlock_irqrestore(&q_ctx->rdy_spinlock, flags);
150 	return &b->vb;
151 }
152 EXPORT_SYMBOL_GPL(v4l2_m2m_next_buf);
153 
154 struct vb2_v4l2_buffer *v4l2_m2m_last_buf(struct v4l2_m2m_queue_ctx *q_ctx)
155 {
156 	struct v4l2_m2m_buffer *b;
157 	unsigned long flags;
158 
159 	spin_lock_irqsave(&q_ctx->rdy_spinlock, flags);
160 
161 	if (list_empty(&q_ctx->rdy_queue)) {
162 		spin_unlock_irqrestore(&q_ctx->rdy_spinlock, flags);
163 		return NULL;
164 	}
165 
166 	b = list_last_entry(&q_ctx->rdy_queue, struct v4l2_m2m_buffer, list);
167 	spin_unlock_irqrestore(&q_ctx->rdy_spinlock, flags);
168 	return &b->vb;
169 }
170 EXPORT_SYMBOL_GPL(v4l2_m2m_last_buf);
171 
172 struct vb2_v4l2_buffer *v4l2_m2m_buf_remove(struct v4l2_m2m_queue_ctx *q_ctx)
173 {
174 	struct v4l2_m2m_buffer *b;
175 	unsigned long flags;
176 
177 	spin_lock_irqsave(&q_ctx->rdy_spinlock, flags);
178 	if (list_empty(&q_ctx->rdy_queue)) {
179 		spin_unlock_irqrestore(&q_ctx->rdy_spinlock, flags);
180 		return NULL;
181 	}
182 	b = list_first_entry(&q_ctx->rdy_queue, struct v4l2_m2m_buffer, list);
183 	list_del(&b->list);
184 	q_ctx->num_rdy--;
185 	spin_unlock_irqrestore(&q_ctx->rdy_spinlock, flags);
186 
187 	return &b->vb;
188 }
189 EXPORT_SYMBOL_GPL(v4l2_m2m_buf_remove);
190 
191 void v4l2_m2m_buf_remove_by_buf(struct v4l2_m2m_queue_ctx *q_ctx,
192 				struct vb2_v4l2_buffer *vbuf)
193 {
194 	struct v4l2_m2m_buffer *b;
195 	unsigned long flags;
196 
197 	spin_lock_irqsave(&q_ctx->rdy_spinlock, flags);
198 	b = container_of(vbuf, struct v4l2_m2m_buffer, vb);
199 	list_del(&b->list);
200 	q_ctx->num_rdy--;
201 	spin_unlock_irqrestore(&q_ctx->rdy_spinlock, flags);
202 }
203 EXPORT_SYMBOL_GPL(v4l2_m2m_buf_remove_by_buf);
204 
205 struct vb2_v4l2_buffer *
206 v4l2_m2m_buf_remove_by_idx(struct v4l2_m2m_queue_ctx *q_ctx, unsigned int idx)
207 
208 {
209 	struct v4l2_m2m_buffer *b, *tmp;
210 	struct vb2_v4l2_buffer *ret = NULL;
211 	unsigned long flags;
212 
213 	spin_lock_irqsave(&q_ctx->rdy_spinlock, flags);
214 	list_for_each_entry_safe(b, tmp, &q_ctx->rdy_queue, list) {
215 		if (b->vb.vb2_buf.index == idx) {
216 			list_del(&b->list);
217 			q_ctx->num_rdy--;
218 			ret = &b->vb;
219 			break;
220 		}
221 	}
222 	spin_unlock_irqrestore(&q_ctx->rdy_spinlock, flags);
223 
224 	return ret;
225 }
226 EXPORT_SYMBOL_GPL(v4l2_m2m_buf_remove_by_idx);
227 
228 /*
229  * Scheduling handlers
230  */
231 
232 void *v4l2_m2m_get_curr_priv(struct v4l2_m2m_dev *m2m_dev)
233 {
234 	unsigned long flags;
235 	void *ret = NULL;
236 
237 	spin_lock_irqsave(&m2m_dev->job_spinlock, flags);
238 	if (m2m_dev->curr_ctx)
239 		ret = m2m_dev->curr_ctx->priv;
240 	spin_unlock_irqrestore(&m2m_dev->job_spinlock, flags);
241 
242 	return ret;
243 }
244 EXPORT_SYMBOL(v4l2_m2m_get_curr_priv);
245 
246 /**
247  * v4l2_m2m_try_run() - select next job to perform and run it if possible
248  * @m2m_dev: per-device context
249  *
250  * Get next transaction (if present) from the waiting jobs list and run it.
251  *
252  * Note that this function can run on a given v4l2_m2m_ctx context,
253  * but call .device_run for another context.
254  */
255 static void v4l2_m2m_try_run(struct v4l2_m2m_dev *m2m_dev)
256 {
257 	unsigned long flags;
258 
259 	spin_lock_irqsave(&m2m_dev->job_spinlock, flags);
260 	if (NULL != m2m_dev->curr_ctx) {
261 		spin_unlock_irqrestore(&m2m_dev->job_spinlock, flags);
262 		dprintk("Another instance is running, won't run now\n");
263 		return;
264 	}
265 
266 	if (list_empty(&m2m_dev->job_queue)) {
267 		spin_unlock_irqrestore(&m2m_dev->job_spinlock, flags);
268 		dprintk("No job pending\n");
269 		return;
270 	}
271 
272 	if (m2m_dev->job_queue_flags & QUEUE_PAUSED) {
273 		spin_unlock_irqrestore(&m2m_dev->job_spinlock, flags);
274 		dprintk("Running new jobs is paused\n");
275 		return;
276 	}
277 
278 	m2m_dev->curr_ctx = list_first_entry(&m2m_dev->job_queue,
279 				   struct v4l2_m2m_ctx, queue);
280 	m2m_dev->curr_ctx->job_flags |= TRANS_RUNNING;
281 	spin_unlock_irqrestore(&m2m_dev->job_spinlock, flags);
282 
283 	dprintk("Running job on m2m_ctx: %p\n", m2m_dev->curr_ctx);
284 	m2m_dev->m2m_ops->device_run(m2m_dev->curr_ctx->priv);
285 }
286 
287 /*
288  * __v4l2_m2m_try_queue() - queue a job
289  * @m2m_dev: m2m device
290  * @m2m_ctx: m2m context
291  *
292  * Check if this context is ready to queue a job.
293  *
294  * This function can run in interrupt context.
295  */
296 static void __v4l2_m2m_try_queue(struct v4l2_m2m_dev *m2m_dev,
297 				 struct v4l2_m2m_ctx *m2m_ctx)
298 {
299 	unsigned long flags_job;
300 	struct vb2_v4l2_buffer *dst, *src;
301 
302 	dprintk("Trying to schedule a job for m2m_ctx: %p\n", m2m_ctx);
303 
304 	if (!m2m_ctx->out_q_ctx.q.streaming ||
305 	    (!m2m_ctx->cap_q_ctx.q.streaming && !m2m_ctx->ignore_cap_streaming)) {
306 		if (!m2m_ctx->ignore_cap_streaming)
307 			dprintk("Streaming needs to be on for both queues\n");
308 		else
309 			dprintk("Streaming needs to be on for the OUTPUT queue\n");
310 		return;
311 	}
312 
313 	spin_lock_irqsave(&m2m_dev->job_spinlock, flags_job);
314 
315 	/* If the context is aborted then don't schedule it */
316 	if (m2m_ctx->job_flags & TRANS_ABORT) {
317 		dprintk("Aborted context\n");
318 		goto job_unlock;
319 	}
320 
321 	if (m2m_ctx->job_flags & TRANS_QUEUED) {
322 		dprintk("On job queue already\n");
323 		goto job_unlock;
324 	}
325 
326 	src = v4l2_m2m_next_src_buf(m2m_ctx);
327 	dst = v4l2_m2m_next_dst_buf(m2m_ctx);
328 	if (!src && !m2m_ctx->out_q_ctx.buffered) {
329 		dprintk("No input buffers available\n");
330 		goto job_unlock;
331 	}
332 	if (!dst && !m2m_ctx->cap_q_ctx.buffered) {
333 		dprintk("No output buffers available\n");
334 		goto job_unlock;
335 	}
336 
337 	m2m_ctx->new_frame = true;
338 
339 	if (src && dst && dst->is_held &&
340 	    dst->vb2_buf.copied_timestamp &&
341 	    dst->vb2_buf.timestamp != src->vb2_buf.timestamp) {
342 		dprintk("Timestamp mismatch, returning held capture buffer\n");
343 		dst->is_held = false;
344 		v4l2_m2m_dst_buf_remove(m2m_ctx);
345 		v4l2_m2m_buf_done(dst, VB2_BUF_STATE_DONE);
346 		dst = v4l2_m2m_next_dst_buf(m2m_ctx);
347 
348 		if (!dst && !m2m_ctx->cap_q_ctx.buffered) {
349 			dprintk("No output buffers available after returning held buffer\n");
350 			goto job_unlock;
351 		}
352 	}
353 
354 	if (src && dst && (m2m_ctx->out_q_ctx.q.subsystem_flags &
355 			   VB2_V4L2_FL_SUPPORTS_M2M_HOLD_CAPTURE_BUF))
356 		m2m_ctx->new_frame = !dst->vb2_buf.copied_timestamp ||
357 			dst->vb2_buf.timestamp != src->vb2_buf.timestamp;
358 
359 	if (m2m_ctx->has_stopped) {
360 		dprintk("Device has stopped\n");
361 		goto job_unlock;
362 	}
363 
364 	if (m2m_dev->m2m_ops->job_ready
365 		&& (!m2m_dev->m2m_ops->job_ready(m2m_ctx->priv))) {
366 		dprintk("Driver not ready\n");
367 		goto job_unlock;
368 	}
369 
370 	list_add_tail(&m2m_ctx->queue, &m2m_dev->job_queue);
371 	m2m_ctx->job_flags |= TRANS_QUEUED;
372 
373 job_unlock:
374 	spin_unlock_irqrestore(&m2m_dev->job_spinlock, flags_job);
375 }
376 
377 /**
378  * v4l2_m2m_try_schedule() - schedule and possibly run a job for any context
379  * @m2m_ctx: m2m context
380  *
381  * Check if this context is ready to queue a job. If suitable,
382  * run the next queued job on the mem2mem device.
383  *
384  * This function shouldn't run in interrupt context.
385  *
386  * Note that v4l2_m2m_try_schedule() can schedule one job for this context,
387  * and then run another job for another context.
388  */
389 void v4l2_m2m_try_schedule(struct v4l2_m2m_ctx *m2m_ctx)
390 {
391 	struct v4l2_m2m_dev *m2m_dev = m2m_ctx->m2m_dev;
392 
393 	__v4l2_m2m_try_queue(m2m_dev, m2m_ctx);
394 	v4l2_m2m_try_run(m2m_dev);
395 }
396 EXPORT_SYMBOL_GPL(v4l2_m2m_try_schedule);
397 
398 /**
399  * v4l2_m2m_device_run_work() - run pending jobs for the context
400  * @work: Work structure used for scheduling the execution of this function.
401  */
402 static void v4l2_m2m_device_run_work(struct work_struct *work)
403 {
404 	struct v4l2_m2m_dev *m2m_dev =
405 		container_of(work, struct v4l2_m2m_dev, job_work);
406 
407 	v4l2_m2m_try_run(m2m_dev);
408 }
409 
410 /**
411  * v4l2_m2m_cancel_job() - cancel pending jobs for the context
412  * @m2m_ctx: m2m context with jobs to be canceled
413  *
414  * In case of streamoff or release called on any context,
415  * 1] If the context is currently running, then abort job will be called
416  * 2] If the context is queued, then the context will be removed from
417  *    the job_queue
418  */
419 static void v4l2_m2m_cancel_job(struct v4l2_m2m_ctx *m2m_ctx)
420 {
421 	struct v4l2_m2m_dev *m2m_dev;
422 	unsigned long flags;
423 
424 	m2m_dev = m2m_ctx->m2m_dev;
425 	spin_lock_irqsave(&m2m_dev->job_spinlock, flags);
426 
427 	m2m_ctx->job_flags |= TRANS_ABORT;
428 	if (m2m_ctx->job_flags & TRANS_RUNNING) {
429 		spin_unlock_irqrestore(&m2m_dev->job_spinlock, flags);
430 		if (m2m_dev->m2m_ops->job_abort)
431 			m2m_dev->m2m_ops->job_abort(m2m_ctx->priv);
432 		dprintk("m2m_ctx %p running, will wait to complete\n", m2m_ctx);
433 		wait_event(m2m_ctx->finished,
434 				!(m2m_ctx->job_flags & TRANS_RUNNING));
435 	} else if (m2m_ctx->job_flags & TRANS_QUEUED) {
436 		list_del(&m2m_ctx->queue);
437 		m2m_ctx->job_flags &= ~(TRANS_QUEUED | TRANS_RUNNING);
438 		spin_unlock_irqrestore(&m2m_dev->job_spinlock, flags);
439 		dprintk("m2m_ctx: %p had been on queue and was removed\n",
440 			m2m_ctx);
441 	} else {
442 		/* Do nothing, was not on queue/running */
443 		spin_unlock_irqrestore(&m2m_dev->job_spinlock, flags);
444 	}
445 }
446 
447 /*
448  * Schedule the next job, called from v4l2_m2m_job_finish() or
449  * v4l2_m2m_buf_done_and_job_finish().
450  */
451 static void v4l2_m2m_schedule_next_job(struct v4l2_m2m_dev *m2m_dev,
452 				       struct v4l2_m2m_ctx *m2m_ctx)
453 {
454 	/*
455 	 * This instance might have more buffers ready, but since we do not
456 	 * allow more than one job on the job_queue per instance, each has
457 	 * to be scheduled separately after the previous one finishes.
458 	 */
459 	__v4l2_m2m_try_queue(m2m_dev, m2m_ctx);
460 
461 	/*
462 	 * We might be running in atomic context,
463 	 * but the job must be run in non-atomic context.
464 	 */
465 	schedule_work(&m2m_dev->job_work);
466 }
467 
468 /*
469  * Assumes job_spinlock is held, called from v4l2_m2m_job_finish() or
470  * v4l2_m2m_buf_done_and_job_finish().
471  */
472 static bool _v4l2_m2m_job_finish(struct v4l2_m2m_dev *m2m_dev,
473 				 struct v4l2_m2m_ctx *m2m_ctx)
474 {
475 	if (!m2m_dev->curr_ctx || m2m_dev->curr_ctx != m2m_ctx) {
476 		dprintk("Called by an instance not currently running\n");
477 		return false;
478 	}
479 
480 	list_del(&m2m_dev->curr_ctx->queue);
481 	m2m_dev->curr_ctx->job_flags &= ~(TRANS_QUEUED | TRANS_RUNNING);
482 	wake_up(&m2m_dev->curr_ctx->finished);
483 	m2m_dev->curr_ctx = NULL;
484 	return true;
485 }
486 
487 void v4l2_m2m_job_finish(struct v4l2_m2m_dev *m2m_dev,
488 			 struct v4l2_m2m_ctx *m2m_ctx)
489 {
490 	unsigned long flags;
491 	bool schedule_next;
492 
493 	/*
494 	 * This function should not be used for drivers that support
495 	 * holding capture buffers. Those should use
496 	 * v4l2_m2m_buf_done_and_job_finish() instead.
497 	 */
498 	WARN_ON(m2m_ctx->out_q_ctx.q.subsystem_flags &
499 		VB2_V4L2_FL_SUPPORTS_M2M_HOLD_CAPTURE_BUF);
500 	spin_lock_irqsave(&m2m_dev->job_spinlock, flags);
501 	schedule_next = _v4l2_m2m_job_finish(m2m_dev, m2m_ctx);
502 	spin_unlock_irqrestore(&m2m_dev->job_spinlock, flags);
503 
504 	if (schedule_next)
505 		v4l2_m2m_schedule_next_job(m2m_dev, m2m_ctx);
506 }
507 EXPORT_SYMBOL(v4l2_m2m_job_finish);
508 
509 void v4l2_m2m_buf_done_and_job_finish(struct v4l2_m2m_dev *m2m_dev,
510 				      struct v4l2_m2m_ctx *m2m_ctx,
511 				      enum vb2_buffer_state state)
512 {
513 	struct vb2_v4l2_buffer *src_buf, *dst_buf;
514 	bool schedule_next = false;
515 	unsigned long flags;
516 
517 	spin_lock_irqsave(&m2m_dev->job_spinlock, flags);
518 	src_buf = v4l2_m2m_src_buf_remove(m2m_ctx);
519 	dst_buf = v4l2_m2m_next_dst_buf(m2m_ctx);
520 
521 	if (WARN_ON(!src_buf || !dst_buf))
522 		goto unlock;
523 	dst_buf->is_held = src_buf->flags & V4L2_BUF_FLAG_M2M_HOLD_CAPTURE_BUF;
524 	if (!dst_buf->is_held) {
525 		v4l2_m2m_dst_buf_remove(m2m_ctx);
526 		v4l2_m2m_buf_done(dst_buf, state);
527 	}
528 	/*
529 	 * If the request API is being used, returning the OUTPUT
530 	 * (src) buffer will wake-up any process waiting on the
531 	 * request file descriptor.
532 	 *
533 	 * Therefore, return the CAPTURE (dst) buffer first,
534 	 * to avoid signalling the request file descriptor
535 	 * before the CAPTURE buffer is done.
536 	 */
537 	v4l2_m2m_buf_done(src_buf, state);
538 	schedule_next = _v4l2_m2m_job_finish(m2m_dev, m2m_ctx);
539 unlock:
540 	spin_unlock_irqrestore(&m2m_dev->job_spinlock, flags);
541 
542 	if (schedule_next)
543 		v4l2_m2m_schedule_next_job(m2m_dev, m2m_ctx);
544 }
545 EXPORT_SYMBOL(v4l2_m2m_buf_done_and_job_finish);
546 
547 void v4l2_m2m_suspend(struct v4l2_m2m_dev *m2m_dev)
548 {
549 	unsigned long flags;
550 	struct v4l2_m2m_ctx *curr_ctx;
551 
552 	spin_lock_irqsave(&m2m_dev->job_spinlock, flags);
553 	m2m_dev->job_queue_flags |= QUEUE_PAUSED;
554 	curr_ctx = m2m_dev->curr_ctx;
555 	spin_unlock_irqrestore(&m2m_dev->job_spinlock, flags);
556 
557 	if (curr_ctx)
558 		wait_event(curr_ctx->finished,
559 			   !(curr_ctx->job_flags & TRANS_RUNNING));
560 }
561 EXPORT_SYMBOL(v4l2_m2m_suspend);
562 
563 void v4l2_m2m_resume(struct v4l2_m2m_dev *m2m_dev)
564 {
565 	unsigned long flags;
566 
567 	spin_lock_irqsave(&m2m_dev->job_spinlock, flags);
568 	m2m_dev->job_queue_flags &= ~QUEUE_PAUSED;
569 	spin_unlock_irqrestore(&m2m_dev->job_spinlock, flags);
570 
571 	v4l2_m2m_try_run(m2m_dev);
572 }
573 EXPORT_SYMBOL(v4l2_m2m_resume);
574 
575 int v4l2_m2m_reqbufs(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
576 		     struct v4l2_requestbuffers *reqbufs)
577 {
578 	struct vb2_queue *vq;
579 	int ret;
580 
581 	vq = v4l2_m2m_get_vq(m2m_ctx, reqbufs->type);
582 	ret = vb2_reqbufs(vq, reqbufs);
583 	/* If count == 0, then the owner has released all buffers and he
584 	   is no longer owner of the queue. Otherwise we have an owner. */
585 	if (ret == 0)
586 		vq->owner = reqbufs->count ? file->private_data : NULL;
587 
588 	return ret;
589 }
590 EXPORT_SYMBOL_GPL(v4l2_m2m_reqbufs);
591 
592 static void v4l2_m2m_adjust_mem_offset(struct vb2_queue *vq,
593 				       struct v4l2_buffer *buf)
594 {
595 	/* Adjust MMAP memory offsets for the CAPTURE queue */
596 	if (buf->memory == V4L2_MEMORY_MMAP && V4L2_TYPE_IS_CAPTURE(vq->type)) {
597 		if (V4L2_TYPE_IS_MULTIPLANAR(vq->type)) {
598 			unsigned int i;
599 
600 			for (i = 0; i < buf->length; ++i)
601 				buf->m.planes[i].m.mem_offset
602 					+= DST_QUEUE_OFF_BASE;
603 		} else {
604 			buf->m.offset += DST_QUEUE_OFF_BASE;
605 		}
606 	}
607 }
608 
609 int v4l2_m2m_querybuf(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
610 		      struct v4l2_buffer *buf)
611 {
612 	struct vb2_queue *vq;
613 	int ret;
614 
615 	vq = v4l2_m2m_get_vq(m2m_ctx, buf->type);
616 	ret = vb2_querybuf(vq, buf);
617 	if (ret)
618 		return ret;
619 
620 	/* Adjust MMAP memory offsets for the CAPTURE queue */
621 	v4l2_m2m_adjust_mem_offset(vq, buf);
622 
623 	return 0;
624 }
625 EXPORT_SYMBOL_GPL(v4l2_m2m_querybuf);
626 
627 /*
628  * This will add the LAST flag and mark the buffer management
629  * state as stopped.
630  * This is called when the last capture buffer must be flagged as LAST
631  * in draining mode from the encoder/decoder driver buf_queue() callback
632  * or from v4l2_update_last_buf_state() when a capture buffer is available.
633  */
634 void v4l2_m2m_last_buffer_done(struct v4l2_m2m_ctx *m2m_ctx,
635 			       struct vb2_v4l2_buffer *vbuf)
636 {
637 	vbuf->flags |= V4L2_BUF_FLAG_LAST;
638 	vb2_buffer_done(&vbuf->vb2_buf, VB2_BUF_STATE_DONE);
639 
640 	v4l2_m2m_mark_stopped(m2m_ctx);
641 }
642 EXPORT_SYMBOL_GPL(v4l2_m2m_last_buffer_done);
643 
644 /* When stop command is issued, update buffer management state */
645 static int v4l2_update_last_buf_state(struct v4l2_m2m_ctx *m2m_ctx)
646 {
647 	struct vb2_v4l2_buffer *next_dst_buf;
648 
649 	if (m2m_ctx->is_draining)
650 		return -EBUSY;
651 
652 	if (m2m_ctx->has_stopped)
653 		return 0;
654 
655 	m2m_ctx->last_src_buf = v4l2_m2m_last_src_buf(m2m_ctx);
656 	m2m_ctx->is_draining = true;
657 
658 	/*
659 	 * The processing of the last output buffer queued before
660 	 * the STOP command is expected to mark the buffer management
661 	 * state as stopped with v4l2_m2m_mark_stopped().
662 	 */
663 	if (m2m_ctx->last_src_buf)
664 		return 0;
665 
666 	/*
667 	 * In case the output queue is empty, try to mark the last capture
668 	 * buffer as LAST.
669 	 */
670 	next_dst_buf = v4l2_m2m_dst_buf_remove(m2m_ctx);
671 	if (!next_dst_buf) {
672 		/*
673 		 * Wait for the next queued one in encoder/decoder driver
674 		 * buf_queue() callback using the v4l2_m2m_dst_buf_is_last()
675 		 * helper or in v4l2_m2m_qbuf() if encoder/decoder is not yet
676 		 * streaming.
677 		 */
678 		m2m_ctx->next_buf_last = true;
679 		return 0;
680 	}
681 
682 	v4l2_m2m_last_buffer_done(m2m_ctx, next_dst_buf);
683 
684 	return 0;
685 }
686 
687 /*
688  * Updates the encoding/decoding buffer management state, should
689  * be called from encoder/decoder drivers start_streaming()
690  */
691 void v4l2_m2m_update_start_streaming_state(struct v4l2_m2m_ctx *m2m_ctx,
692 					   struct vb2_queue *q)
693 {
694 	/* If start streaming again, untag the last output buffer */
695 	if (V4L2_TYPE_IS_OUTPUT(q->type))
696 		m2m_ctx->last_src_buf = NULL;
697 }
698 EXPORT_SYMBOL_GPL(v4l2_m2m_update_start_streaming_state);
699 
700 /*
701  * Updates the encoding/decoding buffer management state, should
702  * be called from encoder/decoder driver stop_streaming()
703  */
704 void v4l2_m2m_update_stop_streaming_state(struct v4l2_m2m_ctx *m2m_ctx,
705 					  struct vb2_queue *q)
706 {
707 	if (V4L2_TYPE_IS_OUTPUT(q->type)) {
708 		/*
709 		 * If in draining state, either mark next dst buffer as
710 		 * done or flag next one to be marked as done either
711 		 * in encoder/decoder driver buf_queue() callback using
712 		 * the v4l2_m2m_dst_buf_is_last() helper or in v4l2_m2m_qbuf()
713 		 * if encoder/decoder is not yet streaming
714 		 */
715 		if (m2m_ctx->is_draining) {
716 			struct vb2_v4l2_buffer *next_dst_buf;
717 
718 			m2m_ctx->last_src_buf = NULL;
719 			next_dst_buf = v4l2_m2m_dst_buf_remove(m2m_ctx);
720 			if (!next_dst_buf)
721 				m2m_ctx->next_buf_last = true;
722 			else
723 				v4l2_m2m_last_buffer_done(m2m_ctx,
724 							  next_dst_buf);
725 		}
726 	} else {
727 		v4l2_m2m_clear_state(m2m_ctx);
728 	}
729 }
730 EXPORT_SYMBOL_GPL(v4l2_m2m_update_stop_streaming_state);
731 
732 static void v4l2_m2m_force_last_buf_done(struct v4l2_m2m_ctx *m2m_ctx,
733 					 struct vb2_queue *q)
734 {
735 	struct vb2_buffer *vb;
736 	struct vb2_v4l2_buffer *vbuf;
737 	unsigned int i;
738 
739 	if (WARN_ON(q->is_output))
740 		return;
741 	if (list_empty(&q->queued_list))
742 		return;
743 
744 	vb = list_first_entry(&q->queued_list, struct vb2_buffer, queued_entry);
745 	for (i = 0; i < vb->num_planes; i++)
746 		vb2_set_plane_payload(vb, i, 0);
747 
748 	/*
749 	 * Since the buffer hasn't been queued to the ready queue,
750 	 * mark is active and owned before marking it LAST and DONE
751 	 */
752 	vb->state = VB2_BUF_STATE_ACTIVE;
753 	atomic_inc(&q->owned_by_drv_count);
754 
755 	vbuf = to_vb2_v4l2_buffer(vb);
756 	vbuf->field = V4L2_FIELD_NONE;
757 
758 	v4l2_m2m_last_buffer_done(m2m_ctx, vbuf);
759 }
760 
761 int v4l2_m2m_qbuf(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
762 		  struct v4l2_buffer *buf)
763 {
764 	struct video_device *vdev = video_devdata(file);
765 	struct vb2_queue *vq;
766 	int ret;
767 
768 	vq = v4l2_m2m_get_vq(m2m_ctx, buf->type);
769 	if (V4L2_TYPE_IS_CAPTURE(vq->type) &&
770 	    (buf->flags & V4L2_BUF_FLAG_REQUEST_FD)) {
771 		dprintk("%s: requests cannot be used with capture buffers\n",
772 			__func__);
773 		return -EPERM;
774 	}
775 
776 	ret = vb2_qbuf(vq, vdev->v4l2_dev->mdev, buf);
777 	if (ret)
778 		return ret;
779 
780 	/* Adjust MMAP memory offsets for the CAPTURE queue */
781 	v4l2_m2m_adjust_mem_offset(vq, buf);
782 
783 	/*
784 	 * If the capture queue is streaming, but streaming hasn't started
785 	 * on the device, but was asked to stop, mark the previously queued
786 	 * buffer as DONE with LAST flag since it won't be queued on the
787 	 * device.
788 	 */
789 	if (V4L2_TYPE_IS_CAPTURE(vq->type) &&
790 	    vb2_is_streaming(vq) && !vb2_start_streaming_called(vq) &&
791 	   (v4l2_m2m_has_stopped(m2m_ctx) || v4l2_m2m_dst_buf_is_last(m2m_ctx)))
792 		v4l2_m2m_force_last_buf_done(m2m_ctx, vq);
793 	else if (!(buf->flags & V4L2_BUF_FLAG_IN_REQUEST))
794 		v4l2_m2m_try_schedule(m2m_ctx);
795 
796 	return 0;
797 }
798 EXPORT_SYMBOL_GPL(v4l2_m2m_qbuf);
799 
800 int v4l2_m2m_dqbuf(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
801 		   struct v4l2_buffer *buf)
802 {
803 	struct vb2_queue *vq;
804 	int ret;
805 
806 	vq = v4l2_m2m_get_vq(m2m_ctx, buf->type);
807 	ret = vb2_dqbuf(vq, buf, file->f_flags & O_NONBLOCK);
808 	if (ret)
809 		return ret;
810 
811 	/* Adjust MMAP memory offsets for the CAPTURE queue */
812 	v4l2_m2m_adjust_mem_offset(vq, buf);
813 
814 	return 0;
815 }
816 EXPORT_SYMBOL_GPL(v4l2_m2m_dqbuf);
817 
818 int v4l2_m2m_prepare_buf(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
819 			 struct v4l2_buffer *buf)
820 {
821 	struct video_device *vdev = video_devdata(file);
822 	struct vb2_queue *vq;
823 	int ret;
824 
825 	vq = v4l2_m2m_get_vq(m2m_ctx, buf->type);
826 	ret = vb2_prepare_buf(vq, vdev->v4l2_dev->mdev, buf);
827 	if (ret)
828 		return ret;
829 
830 	/* Adjust MMAP memory offsets for the CAPTURE queue */
831 	v4l2_m2m_adjust_mem_offset(vq, buf);
832 
833 	return 0;
834 }
835 EXPORT_SYMBOL_GPL(v4l2_m2m_prepare_buf);
836 
837 int v4l2_m2m_create_bufs(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
838 			 struct v4l2_create_buffers *create)
839 {
840 	struct vb2_queue *vq;
841 
842 	vq = v4l2_m2m_get_vq(m2m_ctx, create->format.type);
843 	return vb2_create_bufs(vq, create);
844 }
845 EXPORT_SYMBOL_GPL(v4l2_m2m_create_bufs);
846 
847 int v4l2_m2m_expbuf(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
848 		  struct v4l2_exportbuffer *eb)
849 {
850 	struct vb2_queue *vq;
851 
852 	vq = v4l2_m2m_get_vq(m2m_ctx, eb->type);
853 	return vb2_expbuf(vq, eb);
854 }
855 EXPORT_SYMBOL_GPL(v4l2_m2m_expbuf);
856 
857 int v4l2_m2m_streamon(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
858 		      enum v4l2_buf_type type)
859 {
860 	struct vb2_queue *vq;
861 	int ret;
862 
863 	vq = v4l2_m2m_get_vq(m2m_ctx, type);
864 	ret = vb2_streamon(vq, type);
865 	if (!ret)
866 		v4l2_m2m_try_schedule(m2m_ctx);
867 
868 	return ret;
869 }
870 EXPORT_SYMBOL_GPL(v4l2_m2m_streamon);
871 
872 int v4l2_m2m_streamoff(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
873 		       enum v4l2_buf_type type)
874 {
875 	struct v4l2_m2m_dev *m2m_dev;
876 	struct v4l2_m2m_queue_ctx *q_ctx;
877 	unsigned long flags_job, flags;
878 	int ret;
879 
880 	/* wait until the current context is dequeued from job_queue */
881 	v4l2_m2m_cancel_job(m2m_ctx);
882 
883 	q_ctx = get_queue_ctx(m2m_ctx, type);
884 	ret = vb2_streamoff(&q_ctx->q, type);
885 	if (ret)
886 		return ret;
887 
888 	m2m_dev = m2m_ctx->m2m_dev;
889 	spin_lock_irqsave(&m2m_dev->job_spinlock, flags_job);
890 	/* We should not be scheduled anymore, since we're dropping a queue. */
891 	if (m2m_ctx->job_flags & TRANS_QUEUED)
892 		list_del(&m2m_ctx->queue);
893 	m2m_ctx->job_flags = 0;
894 
895 	spin_lock_irqsave(&q_ctx->rdy_spinlock, flags);
896 	/* Drop queue, since streamoff returns device to the same state as after
897 	 * calling reqbufs. */
898 	INIT_LIST_HEAD(&q_ctx->rdy_queue);
899 	q_ctx->num_rdy = 0;
900 	spin_unlock_irqrestore(&q_ctx->rdy_spinlock, flags);
901 
902 	if (m2m_dev->curr_ctx == m2m_ctx) {
903 		m2m_dev->curr_ctx = NULL;
904 		wake_up(&m2m_ctx->finished);
905 	}
906 	spin_unlock_irqrestore(&m2m_dev->job_spinlock, flags_job);
907 
908 	return 0;
909 }
910 EXPORT_SYMBOL_GPL(v4l2_m2m_streamoff);
911 
912 static __poll_t v4l2_m2m_poll_for_data(struct file *file,
913 				       struct v4l2_m2m_ctx *m2m_ctx,
914 				       struct poll_table_struct *wait)
915 {
916 	struct vb2_queue *src_q, *dst_q;
917 	__poll_t rc = 0;
918 	unsigned long flags;
919 
920 	src_q = v4l2_m2m_get_src_vq(m2m_ctx);
921 	dst_q = v4l2_m2m_get_dst_vq(m2m_ctx);
922 
923 	/*
924 	 * There has to be at least one buffer queued on each queued_list, which
925 	 * means either in driver already or waiting for driver to claim it
926 	 * and start processing.
927 	 */
928 	if ((!vb2_is_streaming(src_q) || src_q->error ||
929 	     list_empty(&src_q->queued_list)) &&
930 	    (!vb2_is_streaming(dst_q) || dst_q->error ||
931 	     (list_empty(&dst_q->queued_list) && !dst_q->last_buffer_dequeued)))
932 		return EPOLLERR;
933 
934 	spin_lock_irqsave(&src_q->done_lock, flags);
935 	if (!list_empty(&src_q->done_list))
936 		rc |= EPOLLOUT | EPOLLWRNORM;
937 	spin_unlock_irqrestore(&src_q->done_lock, flags);
938 
939 	spin_lock_irqsave(&dst_q->done_lock, flags);
940 	/*
941 	 * If the last buffer was dequeued from the capture queue, signal
942 	 * userspace. DQBUF(CAPTURE) will return -EPIPE.
943 	 */
944 	if (!list_empty(&dst_q->done_list) || dst_q->last_buffer_dequeued)
945 		rc |= EPOLLIN | EPOLLRDNORM;
946 	spin_unlock_irqrestore(&dst_q->done_lock, flags);
947 
948 	return rc;
949 }
950 
951 __poll_t v4l2_m2m_poll(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
952 		       struct poll_table_struct *wait)
953 {
954 	struct video_device *vfd = video_devdata(file);
955 	struct vb2_queue *src_q = v4l2_m2m_get_src_vq(m2m_ctx);
956 	struct vb2_queue *dst_q = v4l2_m2m_get_dst_vq(m2m_ctx);
957 	__poll_t req_events = poll_requested_events(wait);
958 	__poll_t rc = 0;
959 
960 	/*
961 	 * poll_wait() MUST be called on the first invocation on all the
962 	 * potential queues of interest, even if we are not interested in their
963 	 * events during this first call. Failure to do so will result in
964 	 * queue's events to be ignored because the poll_table won't be capable
965 	 * of adding new wait queues thereafter.
966 	 */
967 	poll_wait(file, &src_q->done_wq, wait);
968 	poll_wait(file, &dst_q->done_wq, wait);
969 
970 	if (req_events & (EPOLLOUT | EPOLLWRNORM | EPOLLIN | EPOLLRDNORM))
971 		rc = v4l2_m2m_poll_for_data(file, m2m_ctx, wait);
972 
973 	if (test_bit(V4L2_FL_USES_V4L2_FH, &vfd->flags)) {
974 		struct v4l2_fh *fh = file->private_data;
975 
976 		poll_wait(file, &fh->wait, wait);
977 		if (v4l2_event_pending(fh))
978 			rc |= EPOLLPRI;
979 	}
980 
981 	return rc;
982 }
983 EXPORT_SYMBOL_GPL(v4l2_m2m_poll);
984 
985 int v4l2_m2m_mmap(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
986 			 struct vm_area_struct *vma)
987 {
988 	unsigned long offset = vma->vm_pgoff << PAGE_SHIFT;
989 	struct vb2_queue *vq;
990 
991 	if (offset < DST_QUEUE_OFF_BASE) {
992 		vq = v4l2_m2m_get_src_vq(m2m_ctx);
993 	} else {
994 		vq = v4l2_m2m_get_dst_vq(m2m_ctx);
995 		vma->vm_pgoff -= (DST_QUEUE_OFF_BASE >> PAGE_SHIFT);
996 	}
997 
998 	return vb2_mmap(vq, vma);
999 }
1000 EXPORT_SYMBOL(v4l2_m2m_mmap);
1001 
1002 #ifndef CONFIG_MMU
1003 unsigned long v4l2_m2m_get_unmapped_area(struct file *file, unsigned long addr,
1004 					 unsigned long len, unsigned long pgoff,
1005 					 unsigned long flags)
1006 {
1007 	struct v4l2_fh *fh = file->private_data;
1008 	unsigned long offset = pgoff << PAGE_SHIFT;
1009 	struct vb2_queue *vq;
1010 
1011 	if (offset < DST_QUEUE_OFF_BASE) {
1012 		vq = v4l2_m2m_get_src_vq(fh->m2m_ctx);
1013 	} else {
1014 		vq = v4l2_m2m_get_dst_vq(fh->m2m_ctx);
1015 		pgoff -= (DST_QUEUE_OFF_BASE >> PAGE_SHIFT);
1016 	}
1017 
1018 	return vb2_get_unmapped_area(vq, addr, len, pgoff, flags);
1019 }
1020 EXPORT_SYMBOL_GPL(v4l2_m2m_get_unmapped_area);
1021 #endif
1022 
1023 #if defined(CONFIG_MEDIA_CONTROLLER)
1024 void v4l2_m2m_unregister_media_controller(struct v4l2_m2m_dev *m2m_dev)
1025 {
1026 	media_remove_intf_links(&m2m_dev->intf_devnode->intf);
1027 	media_devnode_remove(m2m_dev->intf_devnode);
1028 
1029 	media_entity_remove_links(m2m_dev->source);
1030 	media_entity_remove_links(&m2m_dev->sink);
1031 	media_entity_remove_links(&m2m_dev->proc);
1032 	media_device_unregister_entity(m2m_dev->source);
1033 	media_device_unregister_entity(&m2m_dev->sink);
1034 	media_device_unregister_entity(&m2m_dev->proc);
1035 	kfree(m2m_dev->source->name);
1036 	kfree(m2m_dev->sink.name);
1037 	kfree(m2m_dev->proc.name);
1038 }
1039 EXPORT_SYMBOL_GPL(v4l2_m2m_unregister_media_controller);
1040 
1041 static int v4l2_m2m_register_entity(struct media_device *mdev,
1042 	struct v4l2_m2m_dev *m2m_dev, enum v4l2_m2m_entity_type type,
1043 	struct video_device *vdev, int function)
1044 {
1045 	struct media_entity *entity;
1046 	struct media_pad *pads;
1047 	char *name;
1048 	unsigned int len;
1049 	int num_pads;
1050 	int ret;
1051 
1052 	switch (type) {
1053 	case MEM2MEM_ENT_TYPE_SOURCE:
1054 		entity = m2m_dev->source;
1055 		pads = &m2m_dev->source_pad;
1056 		pads[0].flags = MEDIA_PAD_FL_SOURCE;
1057 		num_pads = 1;
1058 		break;
1059 	case MEM2MEM_ENT_TYPE_SINK:
1060 		entity = &m2m_dev->sink;
1061 		pads = &m2m_dev->sink_pad;
1062 		pads[0].flags = MEDIA_PAD_FL_SINK;
1063 		num_pads = 1;
1064 		break;
1065 	case MEM2MEM_ENT_TYPE_PROC:
1066 		entity = &m2m_dev->proc;
1067 		pads = m2m_dev->proc_pads;
1068 		pads[0].flags = MEDIA_PAD_FL_SINK;
1069 		pads[1].flags = MEDIA_PAD_FL_SOURCE;
1070 		num_pads = 2;
1071 		break;
1072 	default:
1073 		return -EINVAL;
1074 	}
1075 
1076 	entity->obj_type = MEDIA_ENTITY_TYPE_BASE;
1077 	if (type != MEM2MEM_ENT_TYPE_PROC) {
1078 		entity->info.dev.major = VIDEO_MAJOR;
1079 		entity->info.dev.minor = vdev->minor;
1080 	}
1081 	len = strlen(vdev->name) + 2 + strlen(m2m_entity_name[type]);
1082 	name = kmalloc(len, GFP_KERNEL);
1083 	if (!name)
1084 		return -ENOMEM;
1085 	snprintf(name, len, "%s-%s", vdev->name, m2m_entity_name[type]);
1086 	entity->name = name;
1087 	entity->function = function;
1088 
1089 	ret = media_entity_pads_init(entity, num_pads, pads);
1090 	if (ret) {
1091 		kfree(entity->name);
1092 		entity->name = NULL;
1093 		return ret;
1094 	}
1095 	ret = media_device_register_entity(mdev, entity);
1096 	if (ret) {
1097 		kfree(entity->name);
1098 		entity->name = NULL;
1099 		return ret;
1100 	}
1101 
1102 	return 0;
1103 }
1104 
1105 int v4l2_m2m_register_media_controller(struct v4l2_m2m_dev *m2m_dev,
1106 		struct video_device *vdev, int function)
1107 {
1108 	struct media_device *mdev = vdev->v4l2_dev->mdev;
1109 	struct media_link *link;
1110 	int ret;
1111 
1112 	if (!mdev)
1113 		return 0;
1114 
1115 	/* A memory-to-memory device consists in two
1116 	 * DMA engine and one video processing entities.
1117 	 * The DMA engine entities are linked to a V4L interface
1118 	 */
1119 
1120 	/* Create the three entities with their pads */
1121 	m2m_dev->source = &vdev->entity;
1122 	ret = v4l2_m2m_register_entity(mdev, m2m_dev,
1123 			MEM2MEM_ENT_TYPE_SOURCE, vdev, MEDIA_ENT_F_IO_V4L);
1124 	if (ret)
1125 		return ret;
1126 	ret = v4l2_m2m_register_entity(mdev, m2m_dev,
1127 			MEM2MEM_ENT_TYPE_PROC, vdev, function);
1128 	if (ret)
1129 		goto err_rel_entity0;
1130 	ret = v4l2_m2m_register_entity(mdev, m2m_dev,
1131 			MEM2MEM_ENT_TYPE_SINK, vdev, MEDIA_ENT_F_IO_V4L);
1132 	if (ret)
1133 		goto err_rel_entity1;
1134 
1135 	/* Connect the three entities */
1136 	ret = media_create_pad_link(m2m_dev->source, 0, &m2m_dev->proc, 0,
1137 			MEDIA_LNK_FL_IMMUTABLE | MEDIA_LNK_FL_ENABLED);
1138 	if (ret)
1139 		goto err_rel_entity2;
1140 
1141 	ret = media_create_pad_link(&m2m_dev->proc, 1, &m2m_dev->sink, 0,
1142 			MEDIA_LNK_FL_IMMUTABLE | MEDIA_LNK_FL_ENABLED);
1143 	if (ret)
1144 		goto err_rm_links0;
1145 
1146 	/* Create video interface */
1147 	m2m_dev->intf_devnode = media_devnode_create(mdev,
1148 			MEDIA_INTF_T_V4L_VIDEO, 0,
1149 			VIDEO_MAJOR, vdev->minor);
1150 	if (!m2m_dev->intf_devnode) {
1151 		ret = -ENOMEM;
1152 		goto err_rm_links1;
1153 	}
1154 
1155 	/* Connect the two DMA engines to the interface */
1156 	link = media_create_intf_link(m2m_dev->source,
1157 			&m2m_dev->intf_devnode->intf,
1158 			MEDIA_LNK_FL_IMMUTABLE | MEDIA_LNK_FL_ENABLED);
1159 	if (!link) {
1160 		ret = -ENOMEM;
1161 		goto err_rm_devnode;
1162 	}
1163 
1164 	link = media_create_intf_link(&m2m_dev->sink,
1165 			&m2m_dev->intf_devnode->intf,
1166 			MEDIA_LNK_FL_IMMUTABLE | MEDIA_LNK_FL_ENABLED);
1167 	if (!link) {
1168 		ret = -ENOMEM;
1169 		goto err_rm_intf_link;
1170 	}
1171 	return 0;
1172 
1173 err_rm_intf_link:
1174 	media_remove_intf_links(&m2m_dev->intf_devnode->intf);
1175 err_rm_devnode:
1176 	media_devnode_remove(m2m_dev->intf_devnode);
1177 err_rm_links1:
1178 	media_entity_remove_links(&m2m_dev->sink);
1179 err_rm_links0:
1180 	media_entity_remove_links(&m2m_dev->proc);
1181 	media_entity_remove_links(m2m_dev->source);
1182 err_rel_entity2:
1183 	media_device_unregister_entity(&m2m_dev->proc);
1184 	kfree(m2m_dev->proc.name);
1185 err_rel_entity1:
1186 	media_device_unregister_entity(&m2m_dev->sink);
1187 	kfree(m2m_dev->sink.name);
1188 err_rel_entity0:
1189 	media_device_unregister_entity(m2m_dev->source);
1190 	kfree(m2m_dev->source->name);
1191 	return ret;
1192 	return 0;
1193 }
1194 EXPORT_SYMBOL_GPL(v4l2_m2m_register_media_controller);
1195 #endif
1196 
1197 struct v4l2_m2m_dev *v4l2_m2m_init(const struct v4l2_m2m_ops *m2m_ops)
1198 {
1199 	struct v4l2_m2m_dev *m2m_dev;
1200 
1201 	if (!m2m_ops || WARN_ON(!m2m_ops->device_run))
1202 		return ERR_PTR(-EINVAL);
1203 
1204 	m2m_dev = kzalloc(sizeof *m2m_dev, GFP_KERNEL);
1205 	if (!m2m_dev)
1206 		return ERR_PTR(-ENOMEM);
1207 
1208 	m2m_dev->curr_ctx = NULL;
1209 	m2m_dev->m2m_ops = m2m_ops;
1210 	INIT_LIST_HEAD(&m2m_dev->job_queue);
1211 	spin_lock_init(&m2m_dev->job_spinlock);
1212 	INIT_WORK(&m2m_dev->job_work, v4l2_m2m_device_run_work);
1213 
1214 	return m2m_dev;
1215 }
1216 EXPORT_SYMBOL_GPL(v4l2_m2m_init);
1217 
1218 void v4l2_m2m_release(struct v4l2_m2m_dev *m2m_dev)
1219 {
1220 	kfree(m2m_dev);
1221 }
1222 EXPORT_SYMBOL_GPL(v4l2_m2m_release);
1223 
1224 struct v4l2_m2m_ctx *v4l2_m2m_ctx_init(struct v4l2_m2m_dev *m2m_dev,
1225 		void *drv_priv,
1226 		int (*queue_init)(void *priv, struct vb2_queue *src_vq, struct vb2_queue *dst_vq))
1227 {
1228 	struct v4l2_m2m_ctx *m2m_ctx;
1229 	struct v4l2_m2m_queue_ctx *out_q_ctx, *cap_q_ctx;
1230 	int ret;
1231 
1232 	m2m_ctx = kzalloc(sizeof *m2m_ctx, GFP_KERNEL);
1233 	if (!m2m_ctx)
1234 		return ERR_PTR(-ENOMEM);
1235 
1236 	m2m_ctx->priv = drv_priv;
1237 	m2m_ctx->m2m_dev = m2m_dev;
1238 	init_waitqueue_head(&m2m_ctx->finished);
1239 
1240 	out_q_ctx = &m2m_ctx->out_q_ctx;
1241 	cap_q_ctx = &m2m_ctx->cap_q_ctx;
1242 
1243 	INIT_LIST_HEAD(&out_q_ctx->rdy_queue);
1244 	INIT_LIST_HEAD(&cap_q_ctx->rdy_queue);
1245 	spin_lock_init(&out_q_ctx->rdy_spinlock);
1246 	spin_lock_init(&cap_q_ctx->rdy_spinlock);
1247 
1248 	INIT_LIST_HEAD(&m2m_ctx->queue);
1249 
1250 	ret = queue_init(drv_priv, &out_q_ctx->q, &cap_q_ctx->q);
1251 
1252 	if (ret)
1253 		goto err;
1254 	/*
1255 	 * Both queues should use same the mutex to lock the m2m context.
1256 	 * This lock is used in some v4l2_m2m_* helpers.
1257 	 */
1258 	if (WARN_ON(out_q_ctx->q.lock != cap_q_ctx->q.lock)) {
1259 		ret = -EINVAL;
1260 		goto err;
1261 	}
1262 	m2m_ctx->q_lock = out_q_ctx->q.lock;
1263 
1264 	return m2m_ctx;
1265 err:
1266 	kfree(m2m_ctx);
1267 	return ERR_PTR(ret);
1268 }
1269 EXPORT_SYMBOL_GPL(v4l2_m2m_ctx_init);
1270 
1271 void v4l2_m2m_ctx_release(struct v4l2_m2m_ctx *m2m_ctx)
1272 {
1273 	/* wait until the current context is dequeued from job_queue */
1274 	v4l2_m2m_cancel_job(m2m_ctx);
1275 
1276 	vb2_queue_release(&m2m_ctx->cap_q_ctx.q);
1277 	vb2_queue_release(&m2m_ctx->out_q_ctx.q);
1278 
1279 	kfree(m2m_ctx);
1280 }
1281 EXPORT_SYMBOL_GPL(v4l2_m2m_ctx_release);
1282 
1283 void v4l2_m2m_buf_queue(struct v4l2_m2m_ctx *m2m_ctx,
1284 		struct vb2_v4l2_buffer *vbuf)
1285 {
1286 	struct v4l2_m2m_buffer *b = container_of(vbuf,
1287 				struct v4l2_m2m_buffer, vb);
1288 	struct v4l2_m2m_queue_ctx *q_ctx;
1289 	unsigned long flags;
1290 
1291 	q_ctx = get_queue_ctx(m2m_ctx, vbuf->vb2_buf.vb2_queue->type);
1292 	if (!q_ctx)
1293 		return;
1294 
1295 	spin_lock_irqsave(&q_ctx->rdy_spinlock, flags);
1296 	list_add_tail(&b->list, &q_ctx->rdy_queue);
1297 	q_ctx->num_rdy++;
1298 	spin_unlock_irqrestore(&q_ctx->rdy_spinlock, flags);
1299 }
1300 EXPORT_SYMBOL_GPL(v4l2_m2m_buf_queue);
1301 
1302 void v4l2_m2m_buf_copy_metadata(const struct vb2_v4l2_buffer *out_vb,
1303 				struct vb2_v4l2_buffer *cap_vb,
1304 				bool copy_frame_flags)
1305 {
1306 	u32 mask = V4L2_BUF_FLAG_TIMECODE | V4L2_BUF_FLAG_TSTAMP_SRC_MASK;
1307 
1308 	if (copy_frame_flags)
1309 		mask |= V4L2_BUF_FLAG_KEYFRAME | V4L2_BUF_FLAG_PFRAME |
1310 			V4L2_BUF_FLAG_BFRAME;
1311 
1312 	cap_vb->vb2_buf.timestamp = out_vb->vb2_buf.timestamp;
1313 
1314 	if (out_vb->flags & V4L2_BUF_FLAG_TIMECODE)
1315 		cap_vb->timecode = out_vb->timecode;
1316 	cap_vb->field = out_vb->field;
1317 	cap_vb->flags &= ~mask;
1318 	cap_vb->flags |= out_vb->flags & mask;
1319 	cap_vb->vb2_buf.copied_timestamp = 1;
1320 }
1321 EXPORT_SYMBOL_GPL(v4l2_m2m_buf_copy_metadata);
1322 
1323 void v4l2_m2m_request_queue(struct media_request *req)
1324 {
1325 	struct media_request_object *obj, *obj_safe;
1326 	struct v4l2_m2m_ctx *m2m_ctx = NULL;
1327 
1328 	/*
1329 	 * Queue all objects. Note that buffer objects are at the end of the
1330 	 * objects list, after all other object types. Once buffer objects
1331 	 * are queued, the driver might delete them immediately (if the driver
1332 	 * processes the buffer at once), so we have to use
1333 	 * list_for_each_entry_safe() to handle the case where the object we
1334 	 * queue is deleted.
1335 	 */
1336 	list_for_each_entry_safe(obj, obj_safe, &req->objects, list) {
1337 		struct v4l2_m2m_ctx *m2m_ctx_obj;
1338 		struct vb2_buffer *vb;
1339 
1340 		if (!obj->ops->queue)
1341 			continue;
1342 
1343 		if (vb2_request_object_is_buffer(obj)) {
1344 			/* Sanity checks */
1345 			vb = container_of(obj, struct vb2_buffer, req_obj);
1346 			WARN_ON(!V4L2_TYPE_IS_OUTPUT(vb->vb2_queue->type));
1347 			m2m_ctx_obj = container_of(vb->vb2_queue,
1348 						   struct v4l2_m2m_ctx,
1349 						   out_q_ctx.q);
1350 			WARN_ON(m2m_ctx && m2m_ctx_obj != m2m_ctx);
1351 			m2m_ctx = m2m_ctx_obj;
1352 		}
1353 
1354 		/*
1355 		 * The buffer we queue here can in theory be immediately
1356 		 * unbound, hence the use of list_for_each_entry_safe()
1357 		 * above and why we call the queue op last.
1358 		 */
1359 		obj->ops->queue(obj);
1360 	}
1361 
1362 	WARN_ON(!m2m_ctx);
1363 
1364 	if (m2m_ctx)
1365 		v4l2_m2m_try_schedule(m2m_ctx);
1366 }
1367 EXPORT_SYMBOL_GPL(v4l2_m2m_request_queue);
1368 
1369 /* Videobuf2 ioctl helpers */
1370 
1371 int v4l2_m2m_ioctl_reqbufs(struct file *file, void *priv,
1372 				struct v4l2_requestbuffers *rb)
1373 {
1374 	struct v4l2_fh *fh = file->private_data;
1375 
1376 	return v4l2_m2m_reqbufs(file, fh->m2m_ctx, rb);
1377 }
1378 EXPORT_SYMBOL_GPL(v4l2_m2m_ioctl_reqbufs);
1379 
1380 int v4l2_m2m_ioctl_create_bufs(struct file *file, void *priv,
1381 				struct v4l2_create_buffers *create)
1382 {
1383 	struct v4l2_fh *fh = file->private_data;
1384 
1385 	return v4l2_m2m_create_bufs(file, fh->m2m_ctx, create);
1386 }
1387 EXPORT_SYMBOL_GPL(v4l2_m2m_ioctl_create_bufs);
1388 
1389 int v4l2_m2m_ioctl_remove_bufs(struct file *file, void *priv,
1390 			       struct v4l2_remove_buffers *remove)
1391 {
1392 	struct v4l2_fh *fh = file->private_data;
1393 	struct vb2_queue *q = v4l2_m2m_get_vq(fh->m2m_ctx, remove->type);
1394 
1395 	if (!q)
1396 		return -EINVAL;
1397 	if (q->type != remove->type)
1398 		return -EINVAL;
1399 
1400 	return vb2_core_remove_bufs(q, remove->index, remove->count);
1401 }
1402 EXPORT_SYMBOL_GPL(v4l2_m2m_ioctl_remove_bufs);
1403 
1404 int v4l2_m2m_ioctl_querybuf(struct file *file, void *priv,
1405 				struct v4l2_buffer *buf)
1406 {
1407 	struct v4l2_fh *fh = file->private_data;
1408 
1409 	return v4l2_m2m_querybuf(file, fh->m2m_ctx, buf);
1410 }
1411 EXPORT_SYMBOL_GPL(v4l2_m2m_ioctl_querybuf);
1412 
1413 int v4l2_m2m_ioctl_qbuf(struct file *file, void *priv,
1414 				struct v4l2_buffer *buf)
1415 {
1416 	struct v4l2_fh *fh = file->private_data;
1417 
1418 	return v4l2_m2m_qbuf(file, fh->m2m_ctx, buf);
1419 }
1420 EXPORT_SYMBOL_GPL(v4l2_m2m_ioctl_qbuf);
1421 
1422 int v4l2_m2m_ioctl_dqbuf(struct file *file, void *priv,
1423 				struct v4l2_buffer *buf)
1424 {
1425 	struct v4l2_fh *fh = file->private_data;
1426 
1427 	return v4l2_m2m_dqbuf(file, fh->m2m_ctx, buf);
1428 }
1429 EXPORT_SYMBOL_GPL(v4l2_m2m_ioctl_dqbuf);
1430 
1431 int v4l2_m2m_ioctl_prepare_buf(struct file *file, void *priv,
1432 			       struct v4l2_buffer *buf)
1433 {
1434 	struct v4l2_fh *fh = file->private_data;
1435 
1436 	return v4l2_m2m_prepare_buf(file, fh->m2m_ctx, buf);
1437 }
1438 EXPORT_SYMBOL_GPL(v4l2_m2m_ioctl_prepare_buf);
1439 
1440 int v4l2_m2m_ioctl_expbuf(struct file *file, void *priv,
1441 				struct v4l2_exportbuffer *eb)
1442 {
1443 	struct v4l2_fh *fh = file->private_data;
1444 
1445 	return v4l2_m2m_expbuf(file, fh->m2m_ctx, eb);
1446 }
1447 EXPORT_SYMBOL_GPL(v4l2_m2m_ioctl_expbuf);
1448 
1449 int v4l2_m2m_ioctl_streamon(struct file *file, void *priv,
1450 				enum v4l2_buf_type type)
1451 {
1452 	struct v4l2_fh *fh = file->private_data;
1453 
1454 	return v4l2_m2m_streamon(file, fh->m2m_ctx, type);
1455 }
1456 EXPORT_SYMBOL_GPL(v4l2_m2m_ioctl_streamon);
1457 
1458 int v4l2_m2m_ioctl_streamoff(struct file *file, void *priv,
1459 				enum v4l2_buf_type type)
1460 {
1461 	struct v4l2_fh *fh = file->private_data;
1462 
1463 	return v4l2_m2m_streamoff(file, fh->m2m_ctx, type);
1464 }
1465 EXPORT_SYMBOL_GPL(v4l2_m2m_ioctl_streamoff);
1466 
1467 int v4l2_m2m_ioctl_try_encoder_cmd(struct file *file, void *fh,
1468 				   struct v4l2_encoder_cmd *ec)
1469 {
1470 	if (ec->cmd != V4L2_ENC_CMD_STOP && ec->cmd != V4L2_ENC_CMD_START)
1471 		return -EINVAL;
1472 
1473 	ec->flags = 0;
1474 	return 0;
1475 }
1476 EXPORT_SYMBOL_GPL(v4l2_m2m_ioctl_try_encoder_cmd);
1477 
1478 int v4l2_m2m_ioctl_try_decoder_cmd(struct file *file, void *fh,
1479 				   struct v4l2_decoder_cmd *dc)
1480 {
1481 	if (dc->cmd != V4L2_DEC_CMD_STOP && dc->cmd != V4L2_DEC_CMD_START)
1482 		return -EINVAL;
1483 
1484 	dc->flags = 0;
1485 
1486 	if (dc->cmd == V4L2_DEC_CMD_STOP) {
1487 		dc->stop.pts = 0;
1488 	} else if (dc->cmd == V4L2_DEC_CMD_START) {
1489 		dc->start.speed = 0;
1490 		dc->start.format = V4L2_DEC_START_FMT_NONE;
1491 	}
1492 	return 0;
1493 }
1494 EXPORT_SYMBOL_GPL(v4l2_m2m_ioctl_try_decoder_cmd);
1495 
1496 /*
1497  * Updates the encoding state on ENC_CMD_STOP/ENC_CMD_START
1498  * Should be called from the encoder driver encoder_cmd() callback
1499  */
1500 int v4l2_m2m_encoder_cmd(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
1501 			 struct v4l2_encoder_cmd *ec)
1502 {
1503 	if (ec->cmd != V4L2_ENC_CMD_STOP && ec->cmd != V4L2_ENC_CMD_START)
1504 		return -EINVAL;
1505 
1506 	if (ec->cmd == V4L2_ENC_CMD_STOP)
1507 		return v4l2_update_last_buf_state(m2m_ctx);
1508 
1509 	if (m2m_ctx->is_draining)
1510 		return -EBUSY;
1511 
1512 	if (m2m_ctx->has_stopped)
1513 		m2m_ctx->has_stopped = false;
1514 
1515 	return 0;
1516 }
1517 EXPORT_SYMBOL_GPL(v4l2_m2m_encoder_cmd);
1518 
1519 /*
1520  * Updates the decoding state on DEC_CMD_STOP/DEC_CMD_START
1521  * Should be called from the decoder driver decoder_cmd() callback
1522  */
1523 int v4l2_m2m_decoder_cmd(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
1524 			 struct v4l2_decoder_cmd *dc)
1525 {
1526 	if (dc->cmd != V4L2_DEC_CMD_STOP && dc->cmd != V4L2_DEC_CMD_START)
1527 		return -EINVAL;
1528 
1529 	if (dc->cmd == V4L2_DEC_CMD_STOP)
1530 		return v4l2_update_last_buf_state(m2m_ctx);
1531 
1532 	if (m2m_ctx->is_draining)
1533 		return -EBUSY;
1534 
1535 	if (m2m_ctx->has_stopped)
1536 		m2m_ctx->has_stopped = false;
1537 
1538 	return 0;
1539 }
1540 EXPORT_SYMBOL_GPL(v4l2_m2m_decoder_cmd);
1541 
1542 int v4l2_m2m_ioctl_encoder_cmd(struct file *file, void *priv,
1543 			       struct v4l2_encoder_cmd *ec)
1544 {
1545 	struct v4l2_fh *fh = file->private_data;
1546 
1547 	return v4l2_m2m_encoder_cmd(file, fh->m2m_ctx, ec);
1548 }
1549 EXPORT_SYMBOL_GPL(v4l2_m2m_ioctl_encoder_cmd);
1550 
1551 int v4l2_m2m_ioctl_decoder_cmd(struct file *file, void *priv,
1552 			       struct v4l2_decoder_cmd *dc)
1553 {
1554 	struct v4l2_fh *fh = file->private_data;
1555 
1556 	return v4l2_m2m_decoder_cmd(file, fh->m2m_ctx, dc);
1557 }
1558 EXPORT_SYMBOL_GPL(v4l2_m2m_ioctl_decoder_cmd);
1559 
1560 int v4l2_m2m_ioctl_stateless_try_decoder_cmd(struct file *file, void *fh,
1561 					     struct v4l2_decoder_cmd *dc)
1562 {
1563 	if (dc->cmd != V4L2_DEC_CMD_FLUSH)
1564 		return -EINVAL;
1565 
1566 	dc->flags = 0;
1567 
1568 	return 0;
1569 }
1570 EXPORT_SYMBOL_GPL(v4l2_m2m_ioctl_stateless_try_decoder_cmd);
1571 
1572 int v4l2_m2m_ioctl_stateless_decoder_cmd(struct file *file, void *priv,
1573 					 struct v4l2_decoder_cmd *dc)
1574 {
1575 	struct v4l2_fh *fh = file->private_data;
1576 	struct vb2_v4l2_buffer *out_vb, *cap_vb;
1577 	struct v4l2_m2m_dev *m2m_dev = fh->m2m_ctx->m2m_dev;
1578 	unsigned long flags;
1579 	int ret;
1580 
1581 	ret = v4l2_m2m_ioctl_stateless_try_decoder_cmd(file, priv, dc);
1582 	if (ret < 0)
1583 		return ret;
1584 
1585 	spin_lock_irqsave(&m2m_dev->job_spinlock, flags);
1586 	out_vb = v4l2_m2m_last_src_buf(fh->m2m_ctx);
1587 	cap_vb = v4l2_m2m_last_dst_buf(fh->m2m_ctx);
1588 
1589 	/*
1590 	 * If there is an out buffer pending, then clear any HOLD flag.
1591 	 *
1592 	 * By clearing this flag we ensure that when this output
1593 	 * buffer is processed any held capture buffer will be released.
1594 	 */
1595 	if (out_vb) {
1596 		out_vb->flags &= ~V4L2_BUF_FLAG_M2M_HOLD_CAPTURE_BUF;
1597 	} else if (cap_vb && cap_vb->is_held) {
1598 		/*
1599 		 * If there were no output buffers, but there is a
1600 		 * capture buffer that is held, then release that
1601 		 * buffer.
1602 		 */
1603 		cap_vb->is_held = false;
1604 		v4l2_m2m_dst_buf_remove(fh->m2m_ctx);
1605 		v4l2_m2m_buf_done(cap_vb, VB2_BUF_STATE_DONE);
1606 	}
1607 	spin_unlock_irqrestore(&m2m_dev->job_spinlock, flags);
1608 
1609 	return 0;
1610 }
1611 EXPORT_SYMBOL_GPL(v4l2_m2m_ioctl_stateless_decoder_cmd);
1612 
1613 /*
1614  * v4l2_file_operations helpers. It is assumed here same lock is used
1615  * for the output and the capture buffer queue.
1616  */
1617 
1618 int v4l2_m2m_fop_mmap(struct file *file, struct vm_area_struct *vma)
1619 {
1620 	struct v4l2_fh *fh = file->private_data;
1621 
1622 	return v4l2_m2m_mmap(file, fh->m2m_ctx, vma);
1623 }
1624 EXPORT_SYMBOL_GPL(v4l2_m2m_fop_mmap);
1625 
1626 __poll_t v4l2_m2m_fop_poll(struct file *file, poll_table *wait)
1627 {
1628 	struct v4l2_fh *fh = file->private_data;
1629 	struct v4l2_m2m_ctx *m2m_ctx = fh->m2m_ctx;
1630 	__poll_t ret;
1631 
1632 	if (m2m_ctx->q_lock)
1633 		mutex_lock(m2m_ctx->q_lock);
1634 
1635 	ret = v4l2_m2m_poll(file, m2m_ctx, wait);
1636 
1637 	if (m2m_ctx->q_lock)
1638 		mutex_unlock(m2m_ctx->q_lock);
1639 
1640 	return ret;
1641 }
1642 EXPORT_SYMBOL_GPL(v4l2_m2m_fop_poll);
1643 
1644