2 * Memory-to-memory device framework for Video for Linux 2.
4 * Helper functions for devices that use memory buffers for both source
7 * Copyright (c) 2009 Samsung Electronics Co., Ltd.
8 * Pawel Osciak, <pawel@osciak.com>
9 * Marek Szyprowski, <m.szyprowski@samsung.com>
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by the
13 * Free Software Foundation; either version 2 of the
14 * License, or (at your option) any later version
17 #ifndef _MEDIA_V4L2_MEM2MEM_H
18 #define _MEDIA_V4L2_MEM2MEM_H
20 #include <media/videobuf2-v4l2.h>
23 * struct v4l2_m2m_ops - mem-to-mem device driver callbacks
24 * @device_run: required. Begin the actual job (transaction) inside this
26 * The job does NOT have to end before this callback returns
27 * (and it will be the usual case). When the job finishes,
28 * v4l2_m2m_job_finish() has to be called.
29 * @job_ready: optional. Should return 0 if the driver does not have a job
30 * fully prepared to run yet (i.e. it will not be able to finish a
31 * transaction without sleeping). If not provided, it will be
32 * assumed that one source and one destination buffer are all
33 * that is required for the driver to perform one full transaction.
34 * This method may not sleep.
35 * @job_abort: required. Informs the driver that it has to abort the currently
36 * running transaction as soon as possible (i.e. as soon as it can
37 * stop the device safely; e.g. in the next interrupt handler),
38 * even if the transaction would not have been finished by then.
39 * After the driver performs the necessary steps, it has to call
40 * v4l2_m2m_job_finish() (as if the transaction ended normally).
41 * This function does not have to (and will usually not) wait
42 * until the device enters a state when it can be stopped.
43 * @lock: optional. Define a driver's own lock callback, instead of using
44 * &v4l2_m2m_ctx->q_lock.
45 * @unlock: optional. Define a driver's own unlock callback, instead of
46 * using &v4l2_m2m_ctx->q_lock.
49 void (*device_run)(void *priv);
50 int (*job_ready)(void *priv);
51 void (*job_abort)(void *priv);
52 void (*lock)(void *priv);
53 void (*unlock)(void *priv);
59 * struct v4l2_m2m_queue_ctx - represents a queue for buffers ready to be
62 * @q: pointer to struct &vb2_queue
63 * @rdy_queue: List of V4L2 mem-to-mem queues
64 * @rdy_spinlock: spin lock to protect the struct usage
65 * @num_rdy: number of buffers ready to be processed
66 * @buffered: is the queue buffered?
68 * Queue for buffers ready to be processed as soon as this
69 * instance receives access to the device.
72 struct v4l2_m2m_queue_ctx {
75 struct list_head rdy_queue;
76 spinlock_t rdy_spinlock;
82 * struct v4l2_m2m_ctx - Memory to memory context structure
84 * @q_lock: struct &mutex lock
85 * @m2m_dev: opaque pointer to the internal data to handle M2M context
86 * @cap_q_ctx: Capture (output to memory) queue context
87 * @out_q_ctx: Output (input from memory) queue context
88 * @queue: List of memory to memory contexts
89 * @job_flags: Job queue flags, used internally by v4l2-mem2mem.c:
90 * %TRANS_QUEUED, %TRANS_RUNNING and %TRANS_ABORT.
91 * @finished: Wait queue used to signalize when a job queue finished.
92 * @priv: Instance private data
94 * The memory to memory context is specific to a file handle, NOT to e.g.
98 /* optional cap/out vb2 queues lock */
101 /* internal use only */
102 struct v4l2_m2m_dev *m2m_dev;
104 struct v4l2_m2m_queue_ctx cap_q_ctx;
106 struct v4l2_m2m_queue_ctx out_q_ctx;
108 /* For device job queue */
109 struct list_head queue;
110 unsigned long job_flags;
111 wait_queue_head_t finished;
117 * struct v4l2_m2m_buffer - Memory to memory buffer
119 * @vb: pointer to struct &vb2_v4l2_buffer
120 * @list: list of m2m buffers
122 struct v4l2_m2m_buffer {
123 struct vb2_v4l2_buffer vb;
124 struct list_head list;
128 * v4l2_m2m_get_curr_priv() - return driver private data for the currently
129 * running instance or NULL if no instance is running
131 * @m2m_dev: opaque pointer to the internal data to handle M2M context
133 void *v4l2_m2m_get_curr_priv(struct v4l2_m2m_dev *m2m_dev);
136 * v4l2_m2m_get_vq() - return vb2_queue for the given type
138 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
139 * @type: type of the V4L2 buffer, as defined by enum &v4l2_buf_type
141 struct vb2_queue *v4l2_m2m_get_vq(struct v4l2_m2m_ctx *m2m_ctx,
142 enum v4l2_buf_type type);
145 * v4l2_m2m_try_schedule() - check whether an instance is ready to be added to
146 * the pending job queue and add it if so.
148 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
150 * There are three basic requirements an instance has to meet to be able to run:
151 * 1) at least one source buffer has to be queued,
152 * 2) at least one destination buffer has to be queued,
153 * 3) streaming has to be on.
155 * If a queue is buffered (for example a decoder hardware ringbuffer that has
156 * to be drained before doing streamoff), allow scheduling without v4l2 buffers
159 * There may also be additional, custom requirements. In such case the driver
160 * should supply a custom callback (job_ready in v4l2_m2m_ops) that should
161 * return 1 if the instance is ready.
162 * An example of the above could be an instance that requires more than one
163 * src/dst buffer per transaction.
165 void v4l2_m2m_try_schedule(struct v4l2_m2m_ctx *m2m_ctx);
168 * v4l2_m2m_job_finish() - inform the framework that a job has been finished
169 * and have it clean up
171 * @m2m_dev: opaque pointer to the internal data to handle M2M context
172 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
174 * Called by a driver to yield back the device after it has finished with it.
175 * Should be called as soon as possible after reaching a state which allows
176 * other instances to take control of the device.
178 * This function has to be called only after &v4l2_m2m_ops->device_run
179 * callback has been called on the driver. To prevent recursion, it should
180 * not be called directly from the &v4l2_m2m_ops->device_run callback though.
182 void v4l2_m2m_job_finish(struct v4l2_m2m_dev *m2m_dev,
183 struct v4l2_m2m_ctx *m2m_ctx);
186 v4l2_m2m_buf_done(struct vb2_v4l2_buffer *buf, enum vb2_buffer_state state)
188 vb2_buffer_done(&buf->vb2_buf, state);
192 * v4l2_m2m_reqbufs() - multi-queue-aware REQBUFS multiplexer
194 * @file: pointer to struct &file
195 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
196 * @reqbufs: pointer to struct &v4l2_requestbuffers
198 int v4l2_m2m_reqbufs(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
199 struct v4l2_requestbuffers *reqbufs);
202 * v4l2_m2m_querybuf() - multi-queue-aware QUERYBUF multiplexer
204 * @file: pointer to struct &file
205 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
206 * @buf: pointer to struct &v4l2_buffer
208 * See v4l2_m2m_mmap() documentation for details.
210 int v4l2_m2m_querybuf(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
211 struct v4l2_buffer *buf);
214 * v4l2_m2m_qbuf() - enqueue a source or destination buffer, depending on
217 * @file: pointer to struct &file
218 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
219 * @buf: pointer to struct &v4l2_buffer
221 int v4l2_m2m_qbuf(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
222 struct v4l2_buffer *buf);
225 * v4l2_m2m_dqbuf() - dequeue a source or destination buffer, depending on
228 * @file: pointer to struct &file
229 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
230 * @buf: pointer to struct &v4l2_buffer
232 int v4l2_m2m_dqbuf(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
233 struct v4l2_buffer *buf);
236 * v4l2_m2m_prepare_buf() - prepare a source or destination buffer, depending on
239 * @file: pointer to struct &file
240 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
241 * @buf: pointer to struct &v4l2_buffer
243 int v4l2_m2m_prepare_buf(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
244 struct v4l2_buffer *buf);
247 * v4l2_m2m_create_bufs() - create a source or destination buffer, depending
250 * @file: pointer to struct &file
251 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
252 * @create: pointer to struct &v4l2_create_buffers
254 int v4l2_m2m_create_bufs(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
255 struct v4l2_create_buffers *create);
258 * v4l2_m2m_expbuf() - export a source or destination buffer, depending on
261 * @file: pointer to struct &file
262 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
263 * @eb: pointer to struct &v4l2_exportbuffer
265 int v4l2_m2m_expbuf(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
266 struct v4l2_exportbuffer *eb);
269 * v4l2_m2m_streamon() - turn on streaming for a video queue
271 * @file: pointer to struct &file
272 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
273 * @type: type of the V4L2 buffer, as defined by enum &v4l2_buf_type
275 int v4l2_m2m_streamon(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
276 enum v4l2_buf_type type);
279 * v4l2_m2m_streamoff() - turn off streaming for a video queue
281 * @file: pointer to struct &file
282 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
283 * @type: type of the V4L2 buffer, as defined by enum &v4l2_buf_type
285 int v4l2_m2m_streamoff(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
286 enum v4l2_buf_type type);
289 * v4l2_m2m_poll() - poll replacement, for destination buffers only
291 * @file: pointer to struct &file
292 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
293 * @wait: pointer to struct &poll_table_struct
295 * Call from the driver's poll() function. Will poll both queues. If a buffer
296 * is available to dequeue (with dqbuf) from the source queue, this will
297 * indicate that a non-blocking write can be performed, while read will be
298 * returned in case of the destination queue.
300 unsigned int v4l2_m2m_poll(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
301 struct poll_table_struct *wait);
304 * v4l2_m2m_mmap() - source and destination queues-aware mmap multiplexer
306 * @file: pointer to struct &file
307 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
308 * @vma: pointer to struct &vm_area_struct
310 * Call from driver's mmap() function. Will handle mmap() for both queues
311 * seamlessly for videobuffer, which will receive normal per-queue offsets and
312 * proper videobuf queue pointers. The differentiation is made outside videobuf
313 * by adding a predefined offset to buffers from one of the queues and
314 * subtracting it before passing it back to videobuf. Only drivers (and
315 * thus applications) receive modified offsets.
317 int v4l2_m2m_mmap(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
318 struct vm_area_struct *vma);
321 * v4l2_m2m_init() - initialize per-driver m2m data
323 * @m2m_ops: pointer to struct v4l2_m2m_ops
325 * Usually called from driver's ``probe()`` function.
327 * Return: returns an opaque pointer to the internal data to handle M2M context
329 struct v4l2_m2m_dev *v4l2_m2m_init(const struct v4l2_m2m_ops *m2m_ops);
332 * v4l2_m2m_release() - cleans up and frees a m2m_dev structure
334 * @m2m_dev: opaque pointer to the internal data to handle M2M context
336 * Usually called from driver's ``remove()`` function.
338 void v4l2_m2m_release(struct v4l2_m2m_dev *m2m_dev);
341 * v4l2_m2m_ctx_init() - allocate and initialize a m2m context
343 * @m2m_dev: opaque pointer to the internal data to handle M2M context
344 * @drv_priv: driver's instance private data
345 * @queue_init: a callback for queue type-specific initialization function
346 * to be used for initializing videobuf_queues
348 * Usually called from driver's ``open()`` function.
350 struct v4l2_m2m_ctx *v4l2_m2m_ctx_init(struct v4l2_m2m_dev *m2m_dev,
352 int (*queue_init)(void *priv, struct vb2_queue *src_vq, struct vb2_queue *dst_vq));
354 static inline void v4l2_m2m_set_src_buffered(struct v4l2_m2m_ctx *m2m_ctx,
357 m2m_ctx->out_q_ctx.buffered = buffered;
360 static inline void v4l2_m2m_set_dst_buffered(struct v4l2_m2m_ctx *m2m_ctx,
363 m2m_ctx->cap_q_ctx.buffered = buffered;
367 * v4l2_m2m_ctx_release() - release m2m context
369 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
371 * Usually called from driver's release() function.
373 void v4l2_m2m_ctx_release(struct v4l2_m2m_ctx *m2m_ctx);
376 * v4l2_m2m_buf_queue() - add a buffer to the proper ready buffers list.
378 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
379 * @vbuf: pointer to struct &vb2_v4l2_buffer
381 * Call from videobuf_queue_ops->ops->buf_queue, videobuf_queue_ops callback.
383 void v4l2_m2m_buf_queue(struct v4l2_m2m_ctx *m2m_ctx,
384 struct vb2_v4l2_buffer *vbuf);
387 * v4l2_m2m_num_src_bufs_ready() - return the number of source buffers ready for
390 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
393 unsigned int v4l2_m2m_num_src_bufs_ready(struct v4l2_m2m_ctx *m2m_ctx)
395 return m2m_ctx->out_q_ctx.num_rdy;
399 * v4l2_m2m_num_dst_bufs_ready() - return the number of destination buffers
402 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
405 unsigned int v4l2_m2m_num_dst_bufs_ready(struct v4l2_m2m_ctx *m2m_ctx)
407 return m2m_ctx->cap_q_ctx.num_rdy;
411 * v4l2_m2m_next_buf() - return next buffer from the list of ready buffers
413 * @q_ctx: pointer to struct @v4l2_m2m_queue_ctx
415 void *v4l2_m2m_next_buf(struct v4l2_m2m_queue_ctx *q_ctx);
418 * v4l2_m2m_next_src_buf() - return next source buffer from the list of ready
421 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
423 static inline void *v4l2_m2m_next_src_buf(struct v4l2_m2m_ctx *m2m_ctx)
425 return v4l2_m2m_next_buf(&m2m_ctx->out_q_ctx);
429 * v4l2_m2m_next_dst_buf() - return next destination buffer from the list of
432 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
434 static inline void *v4l2_m2m_next_dst_buf(struct v4l2_m2m_ctx *m2m_ctx)
436 return v4l2_m2m_next_buf(&m2m_ctx->cap_q_ctx);
440 * v4l2_m2m_for_each_dst_buf() - iterate over a list of destination ready
443 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
444 * @b: current buffer of type struct v4l2_m2m_buffer
446 #define v4l2_m2m_for_each_dst_buf(m2m_ctx, b) \
447 list_for_each_entry(b, &m2m_ctx->cap_q_ctx.rdy_queue, list)
450 * v4l2_m2m_for_each_src_buf() - iterate over a list of source ready buffers
452 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
453 * @b: current buffer of type struct v4l2_m2m_buffer
455 #define v4l2_m2m_for_each_src_buf(m2m_ctx, b) \
456 list_for_each_entry(b, &m2m_ctx->out_q_ctx.rdy_queue, list)
459 * v4l2_m2m_for_each_dst_buf_safe() - iterate over a list of destination ready
462 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
463 * @b: current buffer of type struct v4l2_m2m_buffer
464 * @n: used as temporary storage
466 #define v4l2_m2m_for_each_dst_buf_safe(m2m_ctx, b, n) \
467 list_for_each_entry_safe(b, n, &m2m_ctx->cap_q_ctx.rdy_queue, list)
470 * v4l2_m2m_for_each_src_buf_safe() - iterate over a list of source ready
473 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
474 * @b: current buffer of type struct v4l2_m2m_buffer
475 * @n: used as temporary storage
477 #define v4l2_m2m_for_each_src_buf_safe(m2m_ctx, b, n) \
478 list_for_each_entry_safe(b, n, &m2m_ctx->out_q_ctx.rdy_queue, list)
481 * v4l2_m2m_get_src_vq() - return vb2_queue for source buffers
483 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
486 struct vb2_queue *v4l2_m2m_get_src_vq(struct v4l2_m2m_ctx *m2m_ctx)
488 return &m2m_ctx->out_q_ctx.q;
492 * v4l2_m2m_get_dst_vq() - return vb2_queue for destination buffers
494 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
497 struct vb2_queue *v4l2_m2m_get_dst_vq(struct v4l2_m2m_ctx *m2m_ctx)
499 return &m2m_ctx->cap_q_ctx.q;
503 * v4l2_m2m_buf_remove() - take off a buffer from the list of ready buffers and
506 * @q_ctx: pointer to struct @v4l2_m2m_queue_ctx
508 void *v4l2_m2m_buf_remove(struct v4l2_m2m_queue_ctx *q_ctx);
511 * v4l2_m2m_src_buf_remove() - take off a source buffer from the list of ready
512 * buffers and return it
514 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
516 static inline void *v4l2_m2m_src_buf_remove(struct v4l2_m2m_ctx *m2m_ctx)
518 return v4l2_m2m_buf_remove(&m2m_ctx->out_q_ctx);
522 * v4l2_m2m_dst_buf_remove() - take off a destination buffer from the list of
523 * ready buffers and return it
525 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
527 static inline void *v4l2_m2m_dst_buf_remove(struct v4l2_m2m_ctx *m2m_ctx)
529 return v4l2_m2m_buf_remove(&m2m_ctx->cap_q_ctx);
533 * v4l2_m2m_buf_remove_by_buf() - take off exact buffer from the list of ready
536 * @q_ctx: pointer to struct @v4l2_m2m_queue_ctx
537 * @vbuf: the buffer to be removed
539 void v4l2_m2m_buf_remove_by_buf(struct v4l2_m2m_queue_ctx *q_ctx,
540 struct vb2_v4l2_buffer *vbuf);
543 * v4l2_m2m_src_buf_remove_by_buf() - take off exact source buffer from the list
546 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
547 * @vbuf: the buffer to be removed
549 static inline void v4l2_m2m_src_buf_remove_by_buf(struct v4l2_m2m_ctx *m2m_ctx,
550 struct vb2_v4l2_buffer *vbuf)
552 v4l2_m2m_buf_remove_by_buf(&m2m_ctx->out_q_ctx, vbuf);
556 * v4l2_m2m_dst_buf_remove_by_buf() - take off exact destination buffer from the
557 * list of ready buffers
559 * @m2m_ctx: m2m context assigned to the instance given by struct &v4l2_m2m_ctx
560 * @vbuf: the buffer to be removed
562 static inline void v4l2_m2m_dst_buf_remove_by_buf(struct v4l2_m2m_ctx *m2m_ctx,
563 struct vb2_v4l2_buffer *vbuf)
565 v4l2_m2m_buf_remove_by_buf(&m2m_ctx->cap_q_ctx, vbuf);
568 struct vb2_v4l2_buffer *
569 v4l2_m2m_buf_remove_by_idx(struct v4l2_m2m_queue_ctx *q_ctx, unsigned int idx);
571 static inline struct vb2_v4l2_buffer *
572 v4l2_m2m_src_buf_remove_by_idx(struct v4l2_m2m_ctx *m2m_ctx, unsigned int idx)
574 return v4l2_m2m_buf_remove_by_idx(&m2m_ctx->out_q_ctx, idx);
577 static inline struct vb2_v4l2_buffer *
578 v4l2_m2m_dst_buf_remove_by_idx(struct v4l2_m2m_ctx *m2m_ctx, unsigned int idx)
580 return v4l2_m2m_buf_remove_by_idx(&m2m_ctx->cap_q_ctx, idx);
583 /* v4l2 ioctl helpers */
585 int v4l2_m2m_ioctl_reqbufs(struct file *file, void *priv,
586 struct v4l2_requestbuffers *rb);
587 int v4l2_m2m_ioctl_create_bufs(struct file *file, void *fh,
588 struct v4l2_create_buffers *create);
589 int v4l2_m2m_ioctl_querybuf(struct file *file, void *fh,
590 struct v4l2_buffer *buf);
591 int v4l2_m2m_ioctl_expbuf(struct file *file, void *fh,
592 struct v4l2_exportbuffer *eb);
593 int v4l2_m2m_ioctl_qbuf(struct file *file, void *fh,
594 struct v4l2_buffer *buf);
595 int v4l2_m2m_ioctl_dqbuf(struct file *file, void *fh,
596 struct v4l2_buffer *buf);
597 int v4l2_m2m_ioctl_prepare_buf(struct file *file, void *fh,
598 struct v4l2_buffer *buf);
599 int v4l2_m2m_ioctl_streamon(struct file *file, void *fh,
600 enum v4l2_buf_type type);
601 int v4l2_m2m_ioctl_streamoff(struct file *file, void *fh,
602 enum v4l2_buf_type type);
603 int v4l2_m2m_fop_mmap(struct file *file, struct vm_area_struct *vma);
604 unsigned int v4l2_m2m_fop_poll(struct file *file, poll_table *wait);
606 #endif /* _MEDIA_V4L2_MEM2MEM_H */