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