drivers/media/v4l2-core/v4l2-mem2mem.c

   1 /*
   2  * Memory-to-memory device framework for Video for Linux 2 and videobuf.
   3  *
   4  * Helper functions for devices that use videobuf buffers for both their
   5  * source and destination.
   6  *
   7  * Copyright (c) 2009-2010 Samsung Electronics Co., Ltd.
   8  * Pawel Osciak, <pawel@osciak.com>
   9  * Marek Szyprowski, <m.szyprowski@samsung.com>
  10  *
  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 License, or (at your
  14  * option) any later version.
  15  */
  16 #include <linux/module.h>
  17 #include <linux/sched.h>
  18 #include <linux/slab.h>
  19
  20 #include <media/media-device.h>
  21 #include <media/videobuf2-v4l2.h>
  22 #include <media/v4l2-mem2mem.h>
  23 #include <media/v4l2-dev.h>
  24 #include <media/v4l2-device.h>
  25 #include <media/v4l2-fh.h>
  26 #include <media/v4l2-event.h>
  27
  28 MODULE_DESCRIPTION("Mem to mem device framework for videobuf");
  29 MODULE_AUTHOR("Pawel Osciak, <pawel@osciak.com>");
  30 MODULE_LICENSE("GPL");
  31
  32 static bool debug;
  33 module_param(debug, bool, 0644);
  34
  35 #define dprintk(fmt, arg...)                                            \
  36         do {                                                            \
  37                 if (debug)                                              \
  38                         printk(KERN_DEBUG "%s: " fmt, __func__, ## arg);\
  39         } while (0)
  40
  41
  42 /* Instance is already queued on the job_queue */
  43 #define TRANS_QUEUED            (1 << 0)
  44 /* Instance is currently running in hardware */
  45 #define TRANS_RUNNING           (1 << 1)
  46 /* Instance is currently aborting */
  47 #define TRANS_ABORT             (1 << 2)
  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_unregister_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_unregister_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_unregister_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_unregister_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  * @m2m_ops:            driver callbacks
  91  */
  92 struct v4l2_m2m_dev {
  93         struct v4l2_m2m_ctx     *curr_ctx;
  94 #ifdef CONFIG_MEDIA_CONTROLLER
  95         struct media_entity     *source;
  96         struct media_pad        source_pad;
  97         struct media_entity     sink;
  98         struct media_pad        sink_pad;
  99         struct media_entity     proc;
 100         struct media_pad        proc_pads[2];
 101         struct media_intf_devnode *intf_devnode;
 102 #endif
 103
 104         struct list_head        job_queue;
 105         spinlock_t              job_spinlock;
 106
 107         const struct v4l2_m2m_ops *m2m_ops;
 108 };
 109
 110 static struct v4l2_m2m_queue_ctx *get_queue_ctx(struct v4l2_m2m_ctx *m2m_ctx,
 111                                                 enum v4l2_buf_type type)
 112 {
 113         if (V4L2_TYPE_IS_OUTPUT(type))
 114                 return &m2m_ctx->out_q_ctx;
 115         else
 116                 return &m2m_ctx->cap_q_ctx;
 117 }
 118
 119 struct vb2_queue *v4l2_m2m_get_vq(struct v4l2_m2m_ctx *m2m_ctx,
 120                                        enum v4l2_buf_type type)
 121 {
 122         struct v4l2_m2m_queue_ctx *q_ctx;
 123
 124         q_ctx = get_queue_ctx(m2m_ctx, type);
 125         if (!q_ctx)
 126                 return NULL;
 127
 128         return &q_ctx->q;
 129 }
 130 EXPORT_SYMBOL(v4l2_m2m_get_vq);
 131
 132 void *v4l2_m2m_next_buf(struct v4l2_m2m_queue_ctx *q_ctx)
 133 {
 134         struct v4l2_m2m_buffer *b;
 135         unsigned long flags;
 136
 137         spin_lock_irqsave(&q_ctx->rdy_spinlock, flags);
 138
 139         if (list_empty(&q_ctx->rdy_queue)) {
 140                 spin_unlock_irqrestore(&q_ctx->rdy_spinlock, flags);
 141                 return NULL;
 142         }
 143
 144         b = list_first_entry(&q_ctx->rdy_queue, struct v4l2_m2m_buffer, list);
 145         spin_unlock_irqrestore(&q_ctx->rdy_spinlock, flags);
 146         return &b->vb;
 147 }
 148 EXPORT_SYMBOL_GPL(v4l2_m2m_next_buf);
 149
 150 void *v4l2_m2m_last_buf(struct v4l2_m2m_queue_ctx *q_ctx)
 151 {
 152         struct v4l2_m2m_buffer *b;
 153         unsigned long flags;
 154
 155         spin_lock_irqsave(&q_ctx->rdy_spinlock, flags);
 156
 157         if (list_empty(&q_ctx->rdy_queue)) {
 158                 spin_unlock_irqrestore(&q_ctx->rdy_spinlock, flags);
 159                 return NULL;
 160         }
 161
 162         b = list_last_entry(&q_ctx->rdy_queue, struct v4l2_m2m_buffer, list);
 163         spin_unlock_irqrestore(&q_ctx->rdy_spinlock, flags);
 164         return &b->vb;
 165 }
 166 EXPORT_SYMBOL_GPL(v4l2_m2m_last_buf);
 167
 168 void *v4l2_m2m_buf_remove(struct v4l2_m2m_queue_ctx *q_ctx)
 169 {
 170         struct v4l2_m2m_buffer *b;
 171         unsigned long flags;
 172
 173         spin_lock_irqsave(&q_ctx->rdy_spinlock, flags);
 174         if (list_empty(&q_ctx->rdy_queue)) {
 175                 spin_unlock_irqrestore(&q_ctx->rdy_spinlock, flags);
 176                 return NULL;
 177         }
 178         b = list_first_entry(&q_ctx->rdy_queue, struct v4l2_m2m_buffer, list);
 179         list_del(&b->list);
 180         q_ctx->num_rdy--;
 181         spin_unlock_irqrestore(&q_ctx->rdy_spinlock, flags);
 182
 183         return &b->vb;
 184 }
 185 EXPORT_SYMBOL_GPL(v4l2_m2m_buf_remove);
 186
 187 void v4l2_m2m_buf_remove_by_buf(struct v4l2_m2m_queue_ctx *q_ctx,
 188                                 struct vb2_v4l2_buffer *vbuf)
 189 {
 190         struct v4l2_m2m_buffer *b;
 191         unsigned long flags;
 192
 193         spin_lock_irqsave(&q_ctx->rdy_spinlock, flags);
 194         b = container_of(vbuf, struct v4l2_m2m_buffer, vb);
 195         list_del(&b->list);
 196         q_ctx->num_rdy--;
 197         spin_unlock_irqrestore(&q_ctx->rdy_spinlock, flags);
 198 }
 199 EXPORT_SYMBOL_GPL(v4l2_m2m_buf_remove_by_buf);
 200
 201 struct vb2_v4l2_buffer *
 202 v4l2_m2m_buf_remove_by_idx(struct v4l2_m2m_queue_ctx *q_ctx, unsigned int idx)
 203
 204 {
 205         struct v4l2_m2m_buffer *b, *tmp;
 206         struct vb2_v4l2_buffer *ret = NULL;
 207         unsigned long flags;
 208
 209         spin_lock_irqsave(&q_ctx->rdy_spinlock, flags);
 210         list_for_each_entry_safe(b, tmp, &q_ctx->rdy_queue, list) {
 211                 if (b->vb.vb2_buf.index == idx) {
 212                         list_del(&b->list);
 213                         q_ctx->num_rdy--;
 214                         ret = &b->vb;
 215                         break;
 216                 }
 217         }
 218         spin_unlock_irqrestore(&q_ctx->rdy_spinlock, flags);
 219
 220         return ret;
 221 }
 222 EXPORT_SYMBOL_GPL(v4l2_m2m_buf_remove_by_idx);
 223
 224 /*
 225  * Scheduling handlers
 226  */
 227
 228 void *v4l2_m2m_get_curr_priv(struct v4l2_m2m_dev *m2m_dev)
 229 {
 230         unsigned long flags;
 231         void *ret = NULL;
 232
 233         spin_lock_irqsave(&m2m_dev->job_spinlock, flags);
 234         if (m2m_dev->curr_ctx)
 235                 ret = m2m_dev->curr_ctx->priv;
 236         spin_unlock_irqrestore(&m2m_dev->job_spinlock, flags);
 237
 238         return ret;
 239 }
 240 EXPORT_SYMBOL(v4l2_m2m_get_curr_priv);
 241
 242 /**
 243  * v4l2_m2m_try_run() - select next job to perform and run it if possible
 244  * @m2m_dev: per-device context
 245  *
 246  * Get next transaction (if present) from the waiting jobs list and run it.
 247  */
 248 static void v4l2_m2m_try_run(struct v4l2_m2m_dev *m2m_dev)
 249 {
 250         unsigned long flags;
 251
 252         spin_lock_irqsave(&m2m_dev->job_spinlock, flags);
 253         if (NULL != m2m_dev->curr_ctx) {
 254                 spin_unlock_irqrestore(&m2m_dev->job_spinlock, flags);
 255                 dprintk("Another instance is running, won't run now\n");
 256                 return;
 257         }
 258
 259         if (list_empty(&m2m_dev->job_queue)) {
 260                 spin_unlock_irqrestore(&m2m_dev->job_spinlock, flags);
 261                 dprintk("No job pending\n");
 262                 return;
 263         }
 264
 265         m2m_dev->curr_ctx = list_first_entry(&m2m_dev->job_queue,
 266                                    struct v4l2_m2m_ctx, queue);
 267         m2m_dev->curr_ctx->job_flags |= TRANS_RUNNING;
 268         spin_unlock_irqrestore(&m2m_dev->job_spinlock, flags);
 269
 270         dprintk("Running job on m2m_ctx: %p\n", m2m_dev->curr_ctx);
 271         m2m_dev->m2m_ops->device_run(m2m_dev->curr_ctx->priv);
 272 }
 273
 274 /*
 275  * __v4l2_m2m_try_queue() - queue a job
 276  * @m2m_dev: m2m device
 277  * @m2m_ctx: m2m context
 278  *
 279  * Check if this context is ready to queue a job.
 280  *
 281  * This function can run in interrupt context.
 282  */
 283 static void __v4l2_m2m_try_queue(struct v4l2_m2m_dev *m2m_dev,
 284                                  struct v4l2_m2m_ctx *m2m_ctx)
 285 {
 286         unsigned long flags_job, flags_out, flags_cap;
 287
 288         dprintk("Trying to schedule a job for m2m_ctx: %p\n", m2m_ctx);
 289
 290         if (!m2m_ctx->out_q_ctx.q.streaming
 291             || !m2m_ctx->cap_q_ctx.q.streaming) {
 292                 dprintk("Streaming needs to be on for both queues\n");
 293                 return;
 294         }
 295
 296         spin_lock_irqsave(&m2m_dev->job_spinlock, flags_job);
 297
 298         /* If the context is aborted then don't schedule it */
 299         if (m2m_ctx->job_flags & TRANS_ABORT) {
 300                 spin_unlock_irqrestore(&m2m_dev->job_spinlock, flags_job);
 301                 dprintk("Aborted context\n");
 302                 return;
 303         }
 304
 305         if (m2m_ctx->job_flags & TRANS_QUEUED) {
 306                 spin_unlock_irqrestore(&m2m_dev->job_spinlock, flags_job);
 307                 dprintk("On job queue already\n");
 308                 return;
 309         }
 310
 311         spin_lock_irqsave(&m2m_ctx->out_q_ctx.rdy_spinlock, flags_out);
 312         if (list_empty(&m2m_ctx->out_q_ctx.rdy_queue)
 313             && !m2m_ctx->out_q_ctx.buffered) {
 314                 spin_unlock_irqrestore(&m2m_ctx->out_q_ctx.rdy_spinlock,
 315                                         flags_out);
 316                 spin_unlock_irqrestore(&m2m_dev->job_spinlock, flags_job);
 317                 dprintk("No input buffers available\n");
 318                 return;
 319         }
 320         spin_lock_irqsave(&m2m_ctx->cap_q_ctx.rdy_spinlock, flags_cap);
 321         if (list_empty(&m2m_ctx->cap_q_ctx.rdy_queue)
 322             && !m2m_ctx->cap_q_ctx.buffered) {
 323                 spin_unlock_irqrestore(&m2m_ctx->cap_q_ctx.rdy_spinlock,
 324                                         flags_cap);
 325                 spin_unlock_irqrestore(&m2m_ctx->out_q_ctx.rdy_spinlock,
 326                                         flags_out);
 327                 spin_unlock_irqrestore(&m2m_dev->job_spinlock, flags_job);
 328                 dprintk("No output buffers available\n");
 329                 return;
 330         }
 331         spin_unlock_irqrestore(&m2m_ctx->cap_q_ctx.rdy_spinlock, flags_cap);
 332         spin_unlock_irqrestore(&m2m_ctx->out_q_ctx.rdy_spinlock, flags_out);
 333
 334         if (m2m_dev->m2m_ops->job_ready
 335                 && (!m2m_dev->m2m_ops->job_ready(m2m_ctx->priv))) {
 336                 spin_unlock_irqrestore(&m2m_dev->job_spinlock, flags_job);
 337                 dprintk("Driver not ready\n");
 338                 return;
 339         }
 340
 341         list_add_tail(&m2m_ctx->queue, &m2m_dev->job_queue);
 342         m2m_ctx->job_flags |= TRANS_QUEUED;
 343
 344         spin_unlock_irqrestore(&m2m_dev->job_spinlock, flags_job);
 345 }
 346
 347 /**
 348  * v4l2_m2m_try_schedule() - schedule and possibly run a job for any context
 349  * @m2m_ctx: m2m context
 350  *
 351  * Check if this context is ready to queue a job. If suitable,
 352  * run the next queued job on the mem2mem device.
 353  *
 354  * This function shouldn't run in interrupt context.
 355  *
 356  * Note that v4l2_m2m_try_schedule() can schedule one job for this context,
 357  * and then run another job for another context.
 358  */
 359 void v4l2_m2m_try_schedule(struct v4l2_m2m_ctx *m2m_ctx)
 360 {
 361         struct v4l2_m2m_dev *m2m_dev = m2m_ctx->m2m_dev;
 362
 363         __v4l2_m2m_try_queue(m2m_dev, m2m_ctx);
 364         v4l2_m2m_try_run(m2m_dev);
 365 }
 366 EXPORT_SYMBOL_GPL(v4l2_m2m_try_schedule);
 367
 368 /**
 369  * v4l2_m2m_cancel_job() - cancel pending jobs for the context
 370  * @m2m_ctx: m2m context with jobs to be canceled
 371  *
 372  * In case of streamoff or release called on any context,
 373  * 1] If the context is currently running, then abort job will be called
 374  * 2] If the context is queued, then the context will be removed from
 375  *    the job_queue
 376  */
 377 static void v4l2_m2m_cancel_job(struct v4l2_m2m_ctx *m2m_ctx)
 378 {
 379         struct v4l2_m2m_dev *m2m_dev;
 380         unsigned long flags;
 381
 382         m2m_dev = m2m_ctx->m2m_dev;
 383         spin_lock_irqsave(&m2m_dev->job_spinlock, flags);
 384
 385         m2m_ctx->job_flags |= TRANS_ABORT;
 386         if (m2m_ctx->job_flags & TRANS_RUNNING) {
 387                 spin_unlock_irqrestore(&m2m_dev->job_spinlock, flags);
 388                 if (m2m_dev->m2m_ops->job_abort)
 389                         m2m_dev->m2m_ops->job_abort(m2m_ctx->priv);
 390                 dprintk("m2m_ctx %p running, will wait to complete", m2m_ctx);
 391                 wait_event(m2m_ctx->finished,
 392                                 !(m2m_ctx->job_flags & TRANS_RUNNING));
 393         } else if (m2m_ctx->job_flags & TRANS_QUEUED) {
 394                 list_del(&m2m_ctx->queue);
 395                 m2m_ctx->job_flags &= ~(TRANS_QUEUED | TRANS_RUNNING);
 396                 spin_unlock_irqrestore(&m2m_dev->job_spinlock, flags);
 397                 dprintk("m2m_ctx: %p had been on queue and was removed\n",
 398                         m2m_ctx);
 399         } else {
 400                 /* Do nothing, was not on queue/running */
 401                 spin_unlock_irqrestore(&m2m_dev->job_spinlock, flags);
 402         }
 403 }
 404
 405 void v4l2_m2m_job_finish(struct v4l2_m2m_dev *m2m_dev,
 406                          struct v4l2_m2m_ctx *m2m_ctx)
 407 {
 408         unsigned long flags;
 409
 410         spin_lock_irqsave(&m2m_dev->job_spinlock, flags);
 411         if (!m2m_dev->curr_ctx || m2m_dev->curr_ctx != m2m_ctx) {
 412                 spin_unlock_irqrestore(&m2m_dev->job_spinlock, flags);
 413                 dprintk("Called by an instance not currently running\n");
 414                 return;
 415         }
 416
 417         list_del(&m2m_dev->curr_ctx->queue);
 418         m2m_dev->curr_ctx->job_flags &= ~(TRANS_QUEUED | TRANS_RUNNING);
 419         wake_up(&m2m_dev->curr_ctx->finished);
 420         m2m_dev->curr_ctx = NULL;
 421
 422         spin_unlock_irqrestore(&m2m_dev->job_spinlock, flags);
 423
 424         /* This instance might have more buffers ready, but since we do not
 425          * allow more than one job on the job_queue per instance, each has
 426          * to be scheduled separately after the previous one finishes. */
 427         v4l2_m2m_try_schedule(m2m_ctx);
 428 }
 429 EXPORT_SYMBOL(v4l2_m2m_job_finish);
 430
 431 int v4l2_m2m_reqbufs(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
 432                      struct v4l2_requestbuffers *reqbufs)
 433 {
 434         struct vb2_queue *vq;
 435         int ret;
 436
 437         vq = v4l2_m2m_get_vq(m2m_ctx, reqbufs->type);
 438         ret = vb2_reqbufs(vq, reqbufs);
 439         /* If count == 0, then the owner has released all buffers and he
 440            is no longer owner of the queue. Otherwise we have an owner. */
 441         if (ret == 0)
 442                 vq->owner = reqbufs->count ? file->private_data : NULL;
 443
 444         return ret;
 445 }
 446 EXPORT_SYMBOL_GPL(v4l2_m2m_reqbufs);
 447
 448 static void v4l2_m2m_adjust_mem_offset(struct vb2_queue *vq,
 449                                        struct v4l2_buffer *buf)
 450 {
 451         /* Adjust MMAP memory offsets for the CAPTURE queue */
 452         if (buf->memory == V4L2_MEMORY_MMAP && !V4L2_TYPE_IS_OUTPUT(vq->type)) {
 453                 if (V4L2_TYPE_IS_MULTIPLANAR(vq->type)) {
 454                         unsigned int i;
 455
 456                         for (i = 0; i < buf->length; ++i)
 457                                 buf->m.planes[i].m.mem_offset
 458                                         += DST_QUEUE_OFF_BASE;
 459                 } else {
 460                         buf->m.offset += DST_QUEUE_OFF_BASE;
 461                 }
 462         }
 463 }
 464
 465 int v4l2_m2m_querybuf(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
 466                       struct v4l2_buffer *buf)
 467 {
 468         struct vb2_queue *vq;
 469         int ret;
 470
 471         vq = v4l2_m2m_get_vq(m2m_ctx, buf->type);
 472         ret = vb2_querybuf(vq, buf);
 473         if (ret)
 474                 return ret;
 475
 476         /* Adjust MMAP memory offsets for the CAPTURE queue */
 477         v4l2_m2m_adjust_mem_offset(vq, buf);
 478
 479         return 0;
 480 }
 481 EXPORT_SYMBOL_GPL(v4l2_m2m_querybuf);
 482
 483 int v4l2_m2m_qbuf(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
 484                   struct v4l2_buffer *buf)
 485 {
 486         struct vb2_queue *vq;
 487         int ret;
 488
 489         vq = v4l2_m2m_get_vq(m2m_ctx, buf->type);
 490         ret = vb2_qbuf(vq, buf);
 491         if (ret)
 492                 return ret;
 493
 494         /* Adjust MMAP memory offsets for the CAPTURE queue */
 495         v4l2_m2m_adjust_mem_offset(vq, buf);
 496
 497         v4l2_m2m_try_schedule(m2m_ctx);
 498
 499         return 0;
 500 }
 501 EXPORT_SYMBOL_GPL(v4l2_m2m_qbuf);
 502
 503 int v4l2_m2m_dqbuf(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
 504                    struct v4l2_buffer *buf)
 505 {
 506         struct vb2_queue *vq;
 507         int ret;
 508
 509         vq = v4l2_m2m_get_vq(m2m_ctx, buf->type);
 510         ret = vb2_dqbuf(vq, buf, file->f_flags & O_NONBLOCK);
 511         if (ret)
 512                 return ret;
 513
 514         /* Adjust MMAP memory offsets for the CAPTURE queue */
 515         v4l2_m2m_adjust_mem_offset(vq, buf);
 516
 517         return 0;
 518 }
 519 EXPORT_SYMBOL_GPL(v4l2_m2m_dqbuf);
 520
 521 int v4l2_m2m_prepare_buf(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
 522                          struct v4l2_buffer *buf)
 523 {
 524         struct vb2_queue *vq;
 525         int ret;
 526
 527         vq = v4l2_m2m_get_vq(m2m_ctx, buf->type);
 528         ret = vb2_prepare_buf(vq, buf);
 529         if (ret)
 530                 return ret;
 531
 532         /* Adjust MMAP memory offsets for the CAPTURE queue */
 533         v4l2_m2m_adjust_mem_offset(vq, buf);
 534
 535         v4l2_m2m_try_schedule(m2m_ctx);
 536
 537         return 0;
 538 }
 539 EXPORT_SYMBOL_GPL(v4l2_m2m_prepare_buf);
 540
 541 int v4l2_m2m_create_bufs(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
 542                          struct v4l2_create_buffers *create)
 543 {
 544         struct vb2_queue *vq;
 545
 546         vq = v4l2_m2m_get_vq(m2m_ctx, create->format.type);
 547         return vb2_create_bufs(vq, create);
 548 }
 549 EXPORT_SYMBOL_GPL(v4l2_m2m_create_bufs);
 550
 551 int v4l2_m2m_expbuf(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
 552                   struct v4l2_exportbuffer *eb)
 553 {
 554         struct vb2_queue *vq;
 555
 556         vq = v4l2_m2m_get_vq(m2m_ctx, eb->type);
 557         return vb2_expbuf(vq, eb);
 558 }
 559 EXPORT_SYMBOL_GPL(v4l2_m2m_expbuf);
 560
 561 int v4l2_m2m_streamon(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
 562                       enum v4l2_buf_type type)
 563 {
 564         struct vb2_queue *vq;
 565         int ret;
 566
 567         vq = v4l2_m2m_get_vq(m2m_ctx, type);
 568         ret = vb2_streamon(vq, type);
 569         if (!ret)
 570                 v4l2_m2m_try_schedule(m2m_ctx);
 571
 572         return ret;
 573 }
 574 EXPORT_SYMBOL_GPL(v4l2_m2m_streamon);
 575
 576 int v4l2_m2m_streamoff(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
 577                        enum v4l2_buf_type type)
 578 {
 579         struct v4l2_m2m_dev *m2m_dev;
 580         struct v4l2_m2m_queue_ctx *q_ctx;
 581         unsigned long flags_job, flags;
 582         int ret;
 583
 584         /* wait until the current context is dequeued from job_queue */
 585         v4l2_m2m_cancel_job(m2m_ctx);
 586
 587         q_ctx = get_queue_ctx(m2m_ctx, type);
 588         ret = vb2_streamoff(&q_ctx->q, type);
 589         if (ret)
 590                 return ret;
 591
 592         m2m_dev = m2m_ctx->m2m_dev;
 593         spin_lock_irqsave(&m2m_dev->job_spinlock, flags_job);
 594         /* We should not be scheduled anymore, since we're dropping a queue. */
 595         if (m2m_ctx->job_flags & TRANS_QUEUED)
 596                 list_del(&m2m_ctx->queue);
 597         m2m_ctx->job_flags = 0;
 598
 599         spin_lock_irqsave(&q_ctx->rdy_spinlock, flags);
 600         /* Drop queue, since streamoff returns device to the same state as after
 601          * calling reqbufs. */
 602         INIT_LIST_HEAD(&q_ctx->rdy_queue);
 603         q_ctx->num_rdy = 0;
 604         spin_unlock_irqrestore(&q_ctx->rdy_spinlock, flags);
 605
 606         if (m2m_dev->curr_ctx == m2m_ctx) {
 607                 m2m_dev->curr_ctx = NULL;
 608                 wake_up(&m2m_ctx->finished);
 609         }
 610         spin_unlock_irqrestore(&m2m_dev->job_spinlock, flags_job);
 611
 612         return 0;
 613 }
 614 EXPORT_SYMBOL_GPL(v4l2_m2m_streamoff);
 615
 616 __poll_t v4l2_m2m_poll(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
 617                            struct poll_table_struct *wait)
 618 {
 619         struct video_device *vfd = video_devdata(file);
 620         __poll_t req_events = poll_requested_events(wait);
 621         struct vb2_queue *src_q, *dst_q;
 622         struct vb2_buffer *src_vb = NULL, *dst_vb = NULL;
 623         __poll_t rc = 0;
 624         unsigned long flags;
 625
 626         if (test_bit(V4L2_FL_USES_V4L2_FH, &vfd->flags)) {
 627                 struct v4l2_fh *fh = file->private_data;
 628
 629                 if (v4l2_event_pending(fh))
 630                         rc = EPOLLPRI;
 631                 else if (req_events & EPOLLPRI)
 632                         poll_wait(file, &fh->wait, wait);
 633                 if (!(req_events & (EPOLLOUT | EPOLLWRNORM | EPOLLIN | EPOLLRDNORM)))
 634                         return rc;
 635         }
 636
 637         src_q = v4l2_m2m_get_src_vq(m2m_ctx);
 638         dst_q = v4l2_m2m_get_dst_vq(m2m_ctx);
 639
 640         /*
 641          * There has to be at least one buffer queued on each queued_list, which
 642          * means either in driver already or waiting for driver to claim it
 643          * and start processing.
 644          */
 645         if ((!src_q->streaming || list_empty(&src_q->queued_list))
 646                 && (!dst_q->streaming || list_empty(&dst_q->queued_list))) {
 647                 rc |= EPOLLERR;
 648                 goto end;
 649         }
 650
 651         spin_lock_irqsave(&src_q->done_lock, flags);
 652         if (list_empty(&src_q->done_list))
 653                 poll_wait(file, &src_q->done_wq, wait);
 654         spin_unlock_irqrestore(&src_q->done_lock, flags);
 655
 656         spin_lock_irqsave(&dst_q->done_lock, flags);
 657         if (list_empty(&dst_q->done_list)) {
 658                 /*
 659                  * If the last buffer was dequeued from the capture queue,
 660                  * return immediately. DQBUF will return -EPIPE.
 661                  */
 662                 if (dst_q->last_buffer_dequeued) {
 663                         spin_unlock_irqrestore(&dst_q->done_lock, flags);
 664                         return rc | EPOLLIN | EPOLLRDNORM;
 665                 }
 666
 667                 poll_wait(file, &dst_q->done_wq, wait);
 668         }
 669         spin_unlock_irqrestore(&dst_q->done_lock, flags);
 670
 671         spin_lock_irqsave(&src_q->done_lock, flags);
 672         if (!list_empty(&src_q->done_list))
 673                 src_vb = list_first_entry(&src_q->done_list, struct vb2_buffer,
 674                                                 done_entry);
 675         if (src_vb && (src_vb->state == VB2_BUF_STATE_DONE
 676                         || src_vb->state == VB2_BUF_STATE_ERROR))
 677                 rc |= EPOLLOUT | EPOLLWRNORM;
 678         spin_unlock_irqrestore(&src_q->done_lock, flags);
 679
 680         spin_lock_irqsave(&dst_q->done_lock, flags);
 681         if (!list_empty(&dst_q->done_list))
 682                 dst_vb = list_first_entry(&dst_q->done_list, struct vb2_buffer,
 683                                                 done_entry);
 684         if (dst_vb && (dst_vb->state == VB2_BUF_STATE_DONE
 685                         || dst_vb->state == VB2_BUF_STATE_ERROR))
 686                 rc |= EPOLLIN | EPOLLRDNORM;
 687         spin_unlock_irqrestore(&dst_q->done_lock, flags);
 688
 689 end:
 690         return rc;
 691 }
 692 EXPORT_SYMBOL_GPL(v4l2_m2m_poll);
 693
 694 int v4l2_m2m_mmap(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
 695                          struct vm_area_struct *vma)
 696 {
 697         unsigned long offset = vma->vm_pgoff << PAGE_SHIFT;
 698         struct vb2_queue *vq;
 699
 700         if (offset < DST_QUEUE_OFF_BASE) {
 701                 vq = v4l2_m2m_get_src_vq(m2m_ctx);
 702         } else {
 703                 vq = v4l2_m2m_get_dst_vq(m2m_ctx);
 704                 vma->vm_pgoff -= (DST_QUEUE_OFF_BASE >> PAGE_SHIFT);
 705         }
 706
 707         return vb2_mmap(vq, vma);
 708 }
 709 EXPORT_SYMBOL(v4l2_m2m_mmap);
 710
 711 #if defined(CONFIG_MEDIA_CONTROLLER)
 712 void v4l2_m2m_unregister_media_controller(struct v4l2_m2m_dev *m2m_dev)
 713 {
 714         media_remove_intf_links(&m2m_dev->intf_devnode->intf);
 715         media_devnode_remove(m2m_dev->intf_devnode);
 716
 717         media_entity_remove_links(m2m_dev->source);
 718         media_entity_remove_links(&m2m_dev->sink);
 719         media_entity_remove_links(&m2m_dev->proc);
 720         media_device_unregister_entity(m2m_dev->source);
 721         media_device_unregister_entity(&m2m_dev->sink);
 722         media_device_unregister_entity(&m2m_dev->proc);
 723         kfree(m2m_dev->source->name);
 724         kfree(m2m_dev->sink.name);
 725         kfree(m2m_dev->proc.name);
 726 }
 727 EXPORT_SYMBOL_GPL(v4l2_m2m_unregister_media_controller);
 728
 729 static int v4l2_m2m_register_entity(struct media_device *mdev,
 730         struct v4l2_m2m_dev *m2m_dev, enum v4l2_m2m_entity_type type,
 731         struct video_device *vdev, int function)
 732 {
 733         struct media_entity *entity;
 734         struct media_pad *pads;
 735         char *name;
 736         unsigned int len;
 737         int num_pads;
 738         int ret;
 739
 740         switch (type) {
 741         case MEM2MEM_ENT_TYPE_SOURCE:
 742                 entity = m2m_dev->source;
 743                 pads = &m2m_dev->source_pad;
 744                 pads[0].flags = MEDIA_PAD_FL_SOURCE;
 745                 num_pads = 1;
 746                 break;
 747         case MEM2MEM_ENT_TYPE_SINK:
 748                 entity = &m2m_dev->sink;
 749                 pads = &m2m_dev->sink_pad;
 750                 pads[0].flags = MEDIA_PAD_FL_SINK;
 751                 num_pads = 1;
 752                 break;
 753         case MEM2MEM_ENT_TYPE_PROC:
 754                 entity = &m2m_dev->proc;
 755                 pads = m2m_dev->proc_pads;
 756                 pads[0].flags = MEDIA_PAD_FL_SINK;
 757                 pads[1].flags = MEDIA_PAD_FL_SOURCE;
 758                 num_pads = 2;
 759                 break;
 760         default:
 761                 return -EINVAL;
 762         }
 763
 764         entity->obj_type = MEDIA_ENTITY_TYPE_BASE;
 765         if (type != MEM2MEM_ENT_TYPE_PROC) {
 766                 entity->info.dev.major = VIDEO_MAJOR;
 767                 entity->info.dev.minor = vdev->minor;
 768         }
 769         len = strlen(vdev->name) + 2 + strlen(m2m_entity_name[type]);
 770         name = kmalloc(len, GFP_KERNEL);
 771         if (!name)
 772                 return -ENOMEM;
 773         snprintf(name, len, "%s-%s", vdev->name, m2m_entity_name[type]);
 774         entity->name = name;
 775         entity->function = function;
 776
 777         ret = media_entity_pads_init(entity, num_pads, pads);
 778         if (ret)
 779                 return ret;
 780         ret = media_device_register_entity(mdev, entity);
 781         if (ret)
 782                 return ret;
 783
 784         return 0;
 785 }
 786
 787 int v4l2_m2m_register_media_controller(struct v4l2_m2m_dev *m2m_dev,
 788                 struct video_device *vdev, int function)
 789 {
 790         struct media_device *mdev = vdev->v4l2_dev->mdev;
 791         struct media_link *link;
 792         int ret;
 793
 794         if (!mdev)
 795                 return 0;
 796
 797         /* A memory-to-memory device consists in two
 798          * DMA engine and one video processing entities.
 799          * The DMA engine entities are linked to a V4L interface
 800          */
 801
 802         /* Create the three entities with their pads */
 803         m2m_dev->source = &vdev->entity;
 804         ret = v4l2_m2m_register_entity(mdev, m2m_dev,
 805                         MEM2MEM_ENT_TYPE_SOURCE, vdev, MEDIA_ENT_F_IO_V4L);
 806         if (ret)
 807                 return ret;
 808         ret = v4l2_m2m_register_entity(mdev, m2m_dev,
 809                         MEM2MEM_ENT_TYPE_PROC, vdev, function);
 810         if (ret)
 811                 goto err_rel_entity0;
 812         ret = v4l2_m2m_register_entity(mdev, m2m_dev,
 813                         MEM2MEM_ENT_TYPE_SINK, vdev, MEDIA_ENT_F_IO_V4L);
 814         if (ret)
 815                 goto err_rel_entity1;
 816
 817         /* Connect the three entities */
 818         ret = media_create_pad_link(m2m_dev->source, 0, &m2m_dev->proc, 0,
 819                         MEDIA_LNK_FL_IMMUTABLE | MEDIA_LNK_FL_ENABLED);
 820         if (ret)
 821                 goto err_rel_entity2;
 822
 823         ret = media_create_pad_link(&m2m_dev->proc, 1, &m2m_dev->sink, 0,
 824                         MEDIA_LNK_FL_IMMUTABLE | MEDIA_LNK_FL_ENABLED);
 825         if (ret)
 826                 goto err_rm_links0;
 827
 828         /* Create video interface */
 829         m2m_dev->intf_devnode = media_devnode_create(mdev,
 830                         MEDIA_INTF_T_V4L_VIDEO, 0,
 831                         VIDEO_MAJOR, vdev->minor);
 832         if (!m2m_dev->intf_devnode) {
 833                 ret = -ENOMEM;
 834                 goto err_rm_links1;
 835         }
 836
 837         /* Connect the two DMA engines to the interface */
 838         link = media_create_intf_link(m2m_dev->source,
 839                         &m2m_dev->intf_devnode->intf,
 840                         MEDIA_LNK_FL_IMMUTABLE | MEDIA_LNK_FL_ENABLED);
 841         if (!link) {
 842                 ret = -ENOMEM;
 843                 goto err_rm_devnode;
 844         }
 845
 846         link = media_create_intf_link(&m2m_dev->sink,
 847                         &m2m_dev->intf_devnode->intf,
 848                         MEDIA_LNK_FL_IMMUTABLE | MEDIA_LNK_FL_ENABLED);
 849         if (!link) {
 850                 ret = -ENOMEM;
 851                 goto err_rm_intf_link;
 852         }
 853         return 0;
 854
 855 err_rm_intf_link:
 856         media_remove_intf_links(&m2m_dev->intf_devnode->intf);
 857 err_rm_devnode:
 858         media_devnode_remove(m2m_dev->intf_devnode);
 859 err_rm_links1:
 860         media_entity_remove_links(&m2m_dev->sink);
 861 err_rm_links0:
 862         media_entity_remove_links(&m2m_dev->proc);
 863         media_entity_remove_links(m2m_dev->source);
 864 err_rel_entity2:
 865         media_device_unregister_entity(&m2m_dev->proc);
 866         kfree(m2m_dev->proc.name);
 867 err_rel_entity1:
 868         media_device_unregister_entity(&m2m_dev->sink);
 869         kfree(m2m_dev->sink.name);
 870 err_rel_entity0:
 871         media_device_unregister_entity(m2m_dev->source);
 872         kfree(m2m_dev->source->name);
 873         return ret;
 874         return 0;
 875 }
 876 EXPORT_SYMBOL_GPL(v4l2_m2m_register_media_controller);
 877 #endif
 878
 879 struct v4l2_m2m_dev *v4l2_m2m_init(const struct v4l2_m2m_ops *m2m_ops)
 880 {
 881         struct v4l2_m2m_dev *m2m_dev;
 882
 883         if (!m2m_ops || WARN_ON(!m2m_ops->device_run))
 884                 return ERR_PTR(-EINVAL);
 885
 886         m2m_dev = kzalloc(sizeof *m2m_dev, GFP_KERNEL);
 887         if (!m2m_dev)
 888                 return ERR_PTR(-ENOMEM);
 889
 890         m2m_dev->curr_ctx = NULL;
 891         m2m_dev->m2m_ops = m2m_ops;
 892         INIT_LIST_HEAD(&m2m_dev->job_queue);
 893         spin_lock_init(&m2m_dev->job_spinlock);
 894
 895         return m2m_dev;
 896 }
 897 EXPORT_SYMBOL_GPL(v4l2_m2m_init);
 898
 899 void v4l2_m2m_release(struct v4l2_m2m_dev *m2m_dev)
 900 {
 901         kfree(m2m_dev);
 902 }
 903 EXPORT_SYMBOL_GPL(v4l2_m2m_release);
 904
 905 struct v4l2_m2m_ctx *v4l2_m2m_ctx_init(struct v4l2_m2m_dev *m2m_dev,
 906                 void *drv_priv,
 907                 int (*queue_init)(void *priv, struct vb2_queue *src_vq, struct vb2_queue *dst_vq))
 908 {
 909         struct v4l2_m2m_ctx *m2m_ctx;
 910         struct v4l2_m2m_queue_ctx *out_q_ctx, *cap_q_ctx;
 911         int ret;
 912
 913         m2m_ctx = kzalloc(sizeof *m2m_ctx, GFP_KERNEL);
 914         if (!m2m_ctx)
 915                 return ERR_PTR(-ENOMEM);
 916
 917         m2m_ctx->priv = drv_priv;
 918         m2m_ctx->m2m_dev = m2m_dev;
 919         init_waitqueue_head(&m2m_ctx->finished);
 920
 921         out_q_ctx = &m2m_ctx->out_q_ctx;
 922         cap_q_ctx = &m2m_ctx->cap_q_ctx;
 923
 924         INIT_LIST_HEAD(&out_q_ctx->rdy_queue);
 925         INIT_LIST_HEAD(&cap_q_ctx->rdy_queue);
 926         spin_lock_init(&out_q_ctx->rdy_spinlock);
 927         spin_lock_init(&cap_q_ctx->rdy_spinlock);
 928
 929         INIT_LIST_HEAD(&m2m_ctx->queue);
 930
 931         ret = queue_init(drv_priv, &out_q_ctx->q, &cap_q_ctx->q);
 932
 933         if (ret)
 934                 goto err;
 935         /*
 936          * If both queues use same mutex assign it as the common buffer
 937          * queues lock to the m2m context. This lock is used in the
 938          * v4l2_m2m_ioctl_* helpers.
 939          */
 940         if (out_q_ctx->q.lock == cap_q_ctx->q.lock)
 941                 m2m_ctx->q_lock = out_q_ctx->q.lock;
 942
 943         return m2m_ctx;
 944 err:
 945         kfree(m2m_ctx);
 946         return ERR_PTR(ret);
 947 }
 948 EXPORT_SYMBOL_GPL(v4l2_m2m_ctx_init);
 949
 950 void v4l2_m2m_ctx_release(struct v4l2_m2m_ctx *m2m_ctx)
 951 {
 952         /* wait until the current context is dequeued from job_queue */
 953         v4l2_m2m_cancel_job(m2m_ctx);
 954
 955         vb2_queue_release(&m2m_ctx->cap_q_ctx.q);
 956         vb2_queue_release(&m2m_ctx->out_q_ctx.q);
 957
 958         kfree(m2m_ctx);
 959 }
 960 EXPORT_SYMBOL_GPL(v4l2_m2m_ctx_release);
 961
 962 void v4l2_m2m_buf_queue(struct v4l2_m2m_ctx *m2m_ctx,
 963                 struct vb2_v4l2_buffer *vbuf)
 964 {
 965         struct v4l2_m2m_buffer *b = container_of(vbuf,
 966                                 struct v4l2_m2m_buffer, vb);
 967         struct v4l2_m2m_queue_ctx *q_ctx;
 968         unsigned long flags;
 969
 970         q_ctx = get_queue_ctx(m2m_ctx, vbuf->vb2_buf.vb2_queue->type);
 971         if (!q_ctx)
 972                 return;
 973
 974         spin_lock_irqsave(&q_ctx->rdy_spinlock, flags);
 975         list_add_tail(&b->list, &q_ctx->rdy_queue);
 976         q_ctx->num_rdy++;
 977         spin_unlock_irqrestore(&q_ctx->rdy_spinlock, flags);
 978 }
 979 EXPORT_SYMBOL_GPL(v4l2_m2m_buf_queue);
 980
 981 /* Videobuf2 ioctl helpers */
 982
 983 int v4l2_m2m_ioctl_reqbufs(struct file *file, void *priv,
 984                                 struct v4l2_requestbuffers *rb)
 985 {
 986         struct v4l2_fh *fh = file->private_data;
 987
 988         return v4l2_m2m_reqbufs(file, fh->m2m_ctx, rb);
 989 }
 990 EXPORT_SYMBOL_GPL(v4l2_m2m_ioctl_reqbufs);
 991
 992 int v4l2_m2m_ioctl_create_bufs(struct file *file, void *priv,
 993                                 struct v4l2_create_buffers *create)
 994 {
 995         struct v4l2_fh *fh = file->private_data;
 996
 997         return v4l2_m2m_create_bufs(file, fh->m2m_ctx, create);
 998 }
 999 EXPORT_SYMBOL_GPL(v4l2_m2m_ioctl_create_bufs);
1000
1001 int v4l2_m2m_ioctl_querybuf(struct file *file, void *priv,
1002                                 struct v4l2_buffer *buf)
1003 {
1004         struct v4l2_fh *fh = file->private_data;
1005
1006         return v4l2_m2m_querybuf(file, fh->m2m_ctx, buf);
1007 }
1008 EXPORT_SYMBOL_GPL(v4l2_m2m_ioctl_querybuf);
1009
1010 int v4l2_m2m_ioctl_qbuf(struct file *file, void *priv,
1011                                 struct v4l2_buffer *buf)
1012 {
1013         struct v4l2_fh *fh = file->private_data;
1014
1015         return v4l2_m2m_qbuf(file, fh->m2m_ctx, buf);
1016 }
1017 EXPORT_SYMBOL_GPL(v4l2_m2m_ioctl_qbuf);
1018
1019 int v4l2_m2m_ioctl_dqbuf(struct file *file, void *priv,
1020                                 struct v4l2_buffer *buf)
1021 {
1022         struct v4l2_fh *fh = file->private_data;
1023
1024         return v4l2_m2m_dqbuf(file, fh->m2m_ctx, buf);
1025 }
1026 EXPORT_SYMBOL_GPL(v4l2_m2m_ioctl_dqbuf);
1027
1028 int v4l2_m2m_ioctl_prepare_buf(struct file *file, void *priv,
1029                                struct v4l2_buffer *buf)
1030 {
1031         struct v4l2_fh *fh = file->private_data;
1032
1033         return v4l2_m2m_prepare_buf(file, fh->m2m_ctx, buf);
1034 }
1035 EXPORT_SYMBOL_GPL(v4l2_m2m_ioctl_prepare_buf);
1036
1037 int v4l2_m2m_ioctl_expbuf(struct file *file, void *priv,
1038                                 struct v4l2_exportbuffer *eb)
1039 {
1040         struct v4l2_fh *fh = file->private_data;
1041
1042         return v4l2_m2m_expbuf(file, fh->m2m_ctx, eb);
1043 }
1044 EXPORT_SYMBOL_GPL(v4l2_m2m_ioctl_expbuf);
1045
1046 int v4l2_m2m_ioctl_streamon(struct file *file, void *priv,
1047                                 enum v4l2_buf_type type)
1048 {
1049         struct v4l2_fh *fh = file->private_data;
1050
1051         return v4l2_m2m_streamon(file, fh->m2m_ctx, type);
1052 }
1053 EXPORT_SYMBOL_GPL(v4l2_m2m_ioctl_streamon);
1054
1055 int v4l2_m2m_ioctl_streamoff(struct file *file, void *priv,
1056                                 enum v4l2_buf_type type)
1057 {
1058         struct v4l2_fh *fh = file->private_data;
1059
1060         return v4l2_m2m_streamoff(file, fh->m2m_ctx, type);
1061 }
1062 EXPORT_SYMBOL_GPL(v4l2_m2m_ioctl_streamoff);
1063
1064 /*
1065  * v4l2_file_operations helpers. It is assumed here same lock is used
1066  * for the output and the capture buffer queue.
1067  */
1068
1069 int v4l2_m2m_fop_mmap(struct file *file, struct vm_area_struct *vma)
1070 {
1071         struct v4l2_fh *fh = file->private_data;
1072
1073         return v4l2_m2m_mmap(file, fh->m2m_ctx, vma);
1074 }
1075 EXPORT_SYMBOL_GPL(v4l2_m2m_fop_mmap);
1076
1077 __poll_t v4l2_m2m_fop_poll(struct file *file, poll_table *wait)
1078 {
1079         struct v4l2_fh *fh = file->private_data;
1080         struct v4l2_m2m_ctx *m2m_ctx = fh->m2m_ctx;
1081         __poll_t ret;
1082
1083         if (m2m_ctx->q_lock)
1084                 mutex_lock(m2m_ctx->q_lock);
1085
1086         ret = v4l2_m2m_poll(file, m2m_ctx, wait);
1087
1088         if (m2m_ctx->q_lock)
1089                 mutex_unlock(m2m_ctx->q_lock);
1090
1091         return ret;
1092 }
1093 EXPORT_SYMBOL_GPL(v4l2_m2m_fop_poll);
1094