drivers/staging/most/aim-v4l2/video.c

   1 /*
   2  * V4L2 AIM - V4L2 Application Interface Module for MostCore
   3  *
   4  * Copyright (C) 2015, Microchip Technology Germany II GmbH & Co. KG
   5  *
   6  * This program is distributed in the hope that it will be useful,
   7  * but WITHOUT ANY WARRANTY; without even the implied warranty of
   8  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   9  * GNU General Public License for more details.
  10  *
  11  * This file is licensed under GPLv2.
  12  */
  13
  14 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  15
  16 #include <linux/module.h>
  17 #include <linux/slab.h>
  18 #include <linux/init.h>
  19 #include <linux/device.h>
  20 #include <linux/suspend.h>
  21 #include <linux/videodev2.h>
  22 #include <linux/mutex.h>
  23 #include <media/v4l2-common.h>
  24 #include <media/v4l2-ioctl.h>
  25 #include <media/v4l2-event.h>
  26 #include <media/v4l2-device.h>
  27 #include <media/v4l2-ctrls.h>
  28 #include <media/v4l2-fh.h>
  29
  30 #include "mostcore.h"
  31
  32
  33 #define V4L2_AIM_MAX_INPUT  1
  34
  35
  36 struct most_video_dev {
  37         struct most_interface *iface;
  38         int ch_idx;
  39         struct list_head list;
  40         bool mute;
  41
  42         struct list_head pending_mbos;
  43         spinlock_t list_lock;
  44
  45         struct v4l2_device v4l2_dev;
  46         atomic_t access_ref;
  47         struct video_device *vdev;
  48         unsigned int ctrl_input;
  49
  50         struct mutex lock;
  51
  52         wait_queue_head_t wait_data;
  53 };
  54
  55 struct aim_fh {
  56         /* must be the first field of this struct! */
  57         struct v4l2_fh fh;
  58         struct most_video_dev *mdev;
  59         u32 offs;
  60 };
  61
  62
  63 static struct list_head video_devices = LIST_HEAD_INIT(video_devices);
  64 static struct spinlock list_lock;
  65
  66
  67 static inline bool data_ready(struct most_video_dev *mdev)
  68 {
  69         return !list_empty(&mdev->pending_mbos);
  70 }
  71
  72 static inline struct mbo *get_top_mbo(struct most_video_dev *mdev)
  73 {
  74         return list_first_entry(&mdev->pending_mbos, struct mbo, list);
  75 }
  76
  77
  78 static int aim_vdev_open(struct file *filp)
  79 {
  80         int ret;
  81         struct video_device *vdev = video_devdata(filp);
  82         struct most_video_dev *mdev = video_drvdata(filp);
  83         struct aim_fh *fh;
  84
  85         pr_info("aim_vdev_open()\n");
  86
  87         switch (vdev->vfl_type) {
  88         case VFL_TYPE_GRABBER:
  89                 break;
  90         default:
  91                 return -EINVAL;
  92         }
  93
  94         fh = kzalloc(sizeof(struct aim_fh), GFP_KERNEL);
  95         if (!fh)
  96                 return -ENOMEM;
  97
  98         if (!atomic_inc_and_test(&mdev->access_ref)) {
  99                 pr_err("too many clients\n");
 100                 ret = -EBUSY;
 101                 goto err_dec;
 102         }
 103
 104         fh->mdev = mdev;
 105         v4l2_fh_init(&fh->fh, vdev);
 106         filp->private_data = fh;
 107
 108         v4l2_fh_add(&fh->fh);
 109
 110         ret = most_start_channel(mdev->iface, mdev->ch_idx);
 111         if (ret) {
 112                 pr_err("most_start_channel() failed\n");
 113                 goto err_rm;
 114         }
 115
 116         return 0;
 117
 118 err_rm:
 119         v4l2_fh_del(&fh->fh);
 120         v4l2_fh_exit(&fh->fh);
 121
 122 err_dec:
 123         atomic_dec(&mdev->access_ref);
 124         kfree(fh);
 125         return ret;
 126 }
 127
 128 static int aim_vdev_close(struct file *filp)
 129 {
 130         struct aim_fh *fh = filp->private_data;
 131         struct most_video_dev *mdev = fh->mdev;
 132         struct mbo *mbo, *tmp;
 133
 134         pr_info("aim_vdev_close()\n");
 135
 136         /*
 137          * We need to put MBOs back before we call most_stop_channel()
 138          * to deallocate MBOs.
 139          * From the other hand mostcore still calling rx_completion()
 140          * to deliver MBOs until most_stop_channel() is called.
 141          * Use mute to work around this issue.
 142          * This must be implemented in core.
 143          */
 144
 145         spin_lock(&mdev->list_lock);
 146         mdev->mute = true;
 147         list_for_each_entry_safe(mbo, tmp, &mdev->pending_mbos, list) {
 148                 list_del(&mbo->list);
 149                 spin_unlock(&mdev->list_lock);
 150                 most_put_mbo(mbo);
 151                 spin_lock(&mdev->list_lock);
 152         }
 153         spin_unlock(&mdev->list_lock);
 154         most_stop_channel(mdev->iface, mdev->ch_idx);
 155         mdev->mute = false;
 156
 157         v4l2_fh_del(&fh->fh);
 158         v4l2_fh_exit(&fh->fh);
 159
 160         atomic_dec(&mdev->access_ref);
 161         kfree(fh);
 162         return 0;
 163 }
 164
 165 static ssize_t aim_vdev_read(struct file *filp, char __user *buf,
 166                              size_t count, loff_t *pos)
 167 {
 168         struct aim_fh *fh = filp->private_data;
 169         struct most_video_dev *mdev = fh->mdev;
 170         int ret = 0;
 171
 172         if (*pos)
 173                 return -ESPIPE;
 174
 175         if (!mdev)
 176                 return -ENODEV;
 177
 178         /* wait for the first buffer */
 179         if (!(filp->f_flags & O_NONBLOCK)) {
 180                 if (wait_event_interruptible(mdev->wait_data, data_ready(mdev)))
 181                         return -ERESTARTSYS;
 182         }
 183
 184         if (!data_ready(mdev))
 185                 return -EAGAIN;
 186
 187         while (count > 0 && data_ready(mdev)) {
 188                 struct mbo *const mbo = get_top_mbo(mdev);
 189                 int const rem = mbo->processed_length - fh->offs;
 190                 int const cnt = rem < count ? rem : count;
 191
 192                 if (copy_to_user(buf, mbo->virt_address + fh->offs, cnt)) {
 193                         pr_err("read: copy_to_user failed\n");
 194                         if (!ret)
 195                                 ret = -EFAULT;
 196                         return ret;
 197                 }
 198
 199                 fh->offs += cnt;
 200                 count -= cnt;
 201                 buf += cnt;
 202                 ret += cnt;
 203
 204                 if (cnt >= rem) {
 205                         fh->offs = 0;
 206                         spin_lock(&mdev->list_lock);
 207                         list_del(&mbo->list);
 208                         spin_unlock(&mdev->list_lock);
 209                         most_put_mbo(mbo);
 210                 }
 211         }
 212         return ret;
 213 }
 214
 215 static unsigned int aim_vdev_poll(struct file *filp, poll_table *wait)
 216 {
 217         struct aim_fh *fh = filp->private_data;
 218         struct most_video_dev *mdev = fh->mdev;
 219         unsigned int mask = 0;
 220
 221         /* only wait if no data is available */
 222         if (!data_ready(mdev))
 223                 poll_wait(filp, &mdev->wait_data, wait);
 224         if (data_ready(mdev))
 225                 mask |= POLLIN | POLLRDNORM;
 226
 227         return mask;
 228 }
 229
 230 static void aim_set_format_struct(struct v4l2_format *f)
 231 {
 232         f->fmt.pix.width = 8;
 233         f->fmt.pix.height = 8;
 234         f->fmt.pix.pixelformat = V4L2_PIX_FMT_MPEG;
 235         f->fmt.pix.bytesperline = 0;
 236         f->fmt.pix.sizeimage = 188 * 2;
 237         f->fmt.pix.colorspace = V4L2_COLORSPACE_REC709;
 238         f->fmt.pix.field = V4L2_FIELD_NONE;
 239         f->fmt.pix.priv = 0;
 240 }
 241
 242 static int aim_set_format(struct most_video_dev *mdev, unsigned int cmd,
 243                           struct v4l2_format *format)
 244 {
 245 #if 0
 246         u32 const pixfmt = format->fmt.pix.pixelformat;
 247         const char *fmt;
 248
 249         if (pixfmt != V4L2_PIX_FMT_MPEG) {
 250                 if (cmd == VIDIOC_TRY_FMT)
 251                         fmt = KERN_ERR "try %c%c%c%c failed\n";
 252                 else
 253                         fmt = KERN_ERR "set %c%c%c%c failed\n";
 254         } else {
 255                 if (cmd == VIDIOC_TRY_FMT)
 256                         fmt = KERN_ERR "try %c%c%c%c\n";
 257                 else
 258                         fmt = KERN_ERR "set %c%c%c%c\n";
 259         }
 260         printk(fmt,
 261                (pixfmt) & 255,
 262                (pixfmt >> 8) & 255,
 263                (pixfmt >> 16) & 255,
 264                (pixfmt >> 24) & 255);
 265 #endif
 266
 267         if (format->fmt.pix.pixelformat != V4L2_PIX_FMT_MPEG)
 268                 return -EINVAL;
 269
 270         if (cmd == VIDIOC_TRY_FMT)
 271                 return 0;
 272
 273         aim_set_format_struct(format);
 274
 275         return 0;
 276 }
 277
 278
 279 static int vidioc_querycap(struct file *file, void  *priv,
 280                            struct v4l2_capability *cap)
 281 {
 282         struct aim_fh *fh = priv;
 283         struct most_video_dev *mdev = fh->mdev;
 284
 285         pr_info("vidioc_querycap()\n");
 286
 287         strlcpy(cap->driver, "v4l2_most_aim", sizeof(cap->driver));
 288         strlcpy(cap->card, "my_card", sizeof(cap->card));
 289         snprintf(cap->bus_info, sizeof(cap->bus_info),
 290                  "%s", mdev->iface->description);
 291
 292         cap->capabilities =
 293                 V4L2_CAP_READWRITE |
 294                 V4L2_CAP_TUNER |
 295                 V4L2_CAP_VIDEO_CAPTURE;
 296         return 0;
 297 }
 298
 299 static int vidioc_enum_fmt_vid_cap(struct file *file, void  *priv,
 300                                    struct v4l2_fmtdesc *f)
 301 {
 302         pr_info("vidioc_enum_fmt_vid_cap() %d\n", f->index);
 303
 304         if (f->index)
 305                 return -EINVAL;
 306
 307         strcpy(f->description, "MPEG");
 308         f->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
 309         f->flags = V4L2_FMT_FLAG_COMPRESSED;
 310         f->pixelformat = V4L2_PIX_FMT_MPEG;
 311
 312         return 0;
 313 }
 314
 315 static int vidioc_g_fmt_vid_cap(struct file *file, void *priv,
 316                                 struct v4l2_format *f)
 317 {
 318         pr_info("vidioc_g_fmt_vid_cap()\n");
 319
 320         aim_set_format_struct(f);
 321         return 0;
 322 }
 323
 324 static int vidioc_try_fmt_vid_cap(struct file *file, void *priv,
 325                                   struct v4l2_format *f)
 326 {
 327         struct aim_fh *fh  = priv;
 328         struct most_video_dev *mdev = fh->mdev;
 329
 330         return aim_set_format(mdev, VIDIOC_TRY_FMT, f);
 331 }
 332
 333 static int vidioc_s_fmt_vid_cap(struct file *file, void *priv,
 334                                 struct v4l2_format *f)
 335 {
 336         struct aim_fh *fh  = priv;
 337         struct most_video_dev *mdev = fh->mdev;
 338
 339         return aim_set_format(mdev, VIDIOC_S_FMT, f);
 340 }
 341
 342 static int vidioc_g_std(struct file *file, void *priv, v4l2_std_id *norm)
 343 {
 344         pr_info("vidioc_g_std()\n");
 345
 346         *norm = V4L2_STD_UNKNOWN;
 347         return 0;
 348 }
 349
 350 static int vidioc_enum_input(struct file *file, void *priv,
 351                              struct v4l2_input *input)
 352 {
 353         struct aim_fh *fh = priv;
 354         struct most_video_dev *mdev = fh->mdev;
 355
 356         if (input->index >= V4L2_AIM_MAX_INPUT)
 357                 return -EINVAL;
 358
 359         strcpy(input->name, "MOST Video");
 360         input->type |= V4L2_INPUT_TYPE_CAMERA;
 361         input->audioset = 0;
 362
 363         input->std = mdev->vdev->tvnorms;
 364
 365         return 0;
 366 }
 367
 368 static int vidioc_g_input(struct file *file, void *priv, unsigned int *i)
 369 {
 370         struct aim_fh *fh = priv;
 371         struct most_video_dev *mdev = fh->mdev;
 372         *i = mdev->ctrl_input;
 373         return 0;
 374 }
 375
 376 static int vidioc_s_input(struct file *file, void *priv, unsigned int index)
 377 {
 378         struct aim_fh *fh = priv;
 379         struct most_video_dev *mdev = fh->mdev;
 380
 381         pr_info("vidioc_s_input(%d)\n", index);
 382
 383         if (index >= V4L2_AIM_MAX_INPUT)
 384                 return -EINVAL;
 385         mdev->ctrl_input = index;
 386         return 0;
 387 }
 388
 389 static struct v4l2_file_operations aim_fops = {
 390         .owner      = THIS_MODULE,
 391         .open       = aim_vdev_open,
 392         .release    = aim_vdev_close,
 393         .read       = aim_vdev_read,
 394         .poll       = aim_vdev_poll,
 395         .unlocked_ioctl = video_ioctl2,
 396 };
 397
 398 static const struct v4l2_ioctl_ops video_ioctl_ops = {
 399         .vidioc_querycap            = vidioc_querycap,
 400         .vidioc_enum_fmt_vid_cap    = vidioc_enum_fmt_vid_cap,
 401         .vidioc_g_fmt_vid_cap       = vidioc_g_fmt_vid_cap,
 402         .vidioc_try_fmt_vid_cap     = vidioc_try_fmt_vid_cap,
 403         .vidioc_s_fmt_vid_cap       = vidioc_s_fmt_vid_cap,
 404         .vidioc_g_std               = vidioc_g_std,
 405         .vidioc_enum_input          = vidioc_enum_input,
 406         .vidioc_g_input             = vidioc_g_input,
 407         .vidioc_s_input             = vidioc_s_input,
 408 };
 409
 410 static const struct video_device aim_videodev_template = {
 411         .fops = &aim_fops,
 412         .release = video_device_release,
 413         .ioctl_ops = &video_ioctl_ops,
 414         .tvnorms = V4L2_STD_UNKNOWN,
 415 };
 416
 417 /**************************************************************************/
 418
 419 static struct most_video_dev *get_aim_dev(
 420         struct most_interface *iface, int channel_idx)
 421 {
 422         struct most_video_dev *mdev, *tmp;
 423
 424         spin_lock(&list_lock);
 425         list_for_each_entry_safe(mdev, tmp, &video_devices, list) {
 426                 if (mdev->iface == iface && mdev->ch_idx == channel_idx) {
 427                         spin_unlock(&list_lock);
 428                         return mdev;
 429                 }
 430         }
 431         spin_unlock(&list_lock);
 432         return NULL;
 433 }
 434
 435 static int aim_rx_data(struct mbo *mbo)
 436 {
 437         struct most_video_dev *mdev =
 438                 get_aim_dev(mbo->ifp, mbo->hdm_channel_id);
 439
 440         if (!mdev)
 441                 return -EIO;
 442
 443         spin_lock(&mdev->list_lock);
 444         if (unlikely(mdev->mute)) {
 445                 spin_unlock(&mdev->list_lock);
 446                 return -EIO;
 447         }
 448
 449         list_add_tail(&mbo->list, &mdev->pending_mbos);
 450         spin_unlock(&mdev->list_lock);
 451         wake_up_interruptible(&mdev->wait_data);
 452         return 0;
 453 }
 454
 455 static int aim_register_videodev(struct most_video_dev *mdev)
 456 {
 457         int retval = -ENOMEM;
 458         int ret;
 459
 460         pr_info("aim_register_videodev()\n");
 461
 462         init_waitqueue_head(&mdev->wait_data);
 463
 464         /* allocate and fill v4l2 video struct */
 465         mdev->vdev = video_device_alloc();
 466         if (!mdev->vdev)
 467                 return -ENOMEM;
 468
 469         /* Fill the video capture device struct */
 470         *mdev->vdev = aim_videodev_template;
 471         mdev->vdev->v4l2_dev = &mdev->v4l2_dev;
 472         mdev->vdev->lock = &mdev->lock;
 473         strcpy(mdev->vdev->name, "most v4l2 aim video");
 474
 475         /* Register the v4l2 device */
 476         video_set_drvdata(mdev->vdev, mdev);
 477         retval = video_register_device(mdev->vdev, VFL_TYPE_GRABBER, -1);
 478         if (retval != 0) {
 479                 pr_err("video_register_device failed (%d)\n", retval);
 480                 ret = -ENODEV;
 481                 goto err_vbi_dev;
 482         }
 483
 484         return 0;
 485
 486 err_vbi_dev:
 487         video_device_release(mdev->vdev);
 488         return ret;
 489 }
 490
 491 static void aim_unregister_videodev(struct most_video_dev *mdev)
 492 {
 493         pr_info("aim_unregister_videodev()\n");
 494
 495         video_unregister_device(mdev->vdev);
 496 }
 497
 498
 499 static void aim_v4l2_dev_release(struct v4l2_device *v4l2_dev)
 500 {
 501         struct most_video_dev *mdev =
 502                 container_of(v4l2_dev, struct most_video_dev, v4l2_dev);
 503
 504         v4l2_device_unregister(v4l2_dev);
 505         kfree(mdev);
 506 }
 507
 508 static int aim_probe_channel(struct most_interface *iface, int channel_idx,
 509                              struct most_channel_config *ccfg,
 510                              struct kobject *parent, char *name)
 511 {
 512         int ret;
 513         struct most_video_dev *mdev = get_aim_dev(iface, channel_idx);
 514
 515         pr_info("aim_probe_channel()\n");
 516
 517         if (mdev) {
 518                 pr_err("channel already linked\n");
 519                 return -EEXIST;
 520         }
 521
 522         if (ccfg->direction != MOST_CH_RX) {
 523                 pr_err("wrong direction, expect rx\n");
 524                 return -EINVAL;
 525         }
 526
 527         if (ccfg->data_type != MOST_CH_SYNC &&
 528             ccfg->data_type != MOST_CH_ISOC_AVP) {
 529                 pr_err("wrong channel type, expect sync or isoc_avp\n");
 530                 return -EINVAL;
 531         }
 532
 533         mdev = kzalloc(sizeof(*mdev), GFP_KERNEL);
 534         if (!mdev)
 535                 return -ENOMEM;
 536
 537         mutex_init(&mdev->lock);
 538         atomic_set(&mdev->access_ref, -1);
 539         spin_lock_init(&mdev->list_lock);
 540         INIT_LIST_HEAD(&mdev->pending_mbos);
 541         mdev->iface = iface;
 542         mdev->ch_idx = channel_idx;
 543         mdev->v4l2_dev.release = aim_v4l2_dev_release;
 544
 545         /* Create the v4l2_device */
 546         strlcpy(mdev->v4l2_dev.name, "most_video_device",
 547                 sizeof(mdev->v4l2_dev.name));
 548         ret = v4l2_device_register(NULL, &mdev->v4l2_dev);
 549         if (ret) {
 550                 pr_err("v4l2_device_register() failed\n");
 551                 kfree(mdev);
 552                 return ret;
 553         }
 554
 555         ret = aim_register_videodev(mdev);
 556         if (ret)
 557                 goto err_unreg;
 558
 559         spin_lock(&list_lock);
 560         list_add(&mdev->list, &video_devices);
 561         spin_unlock(&list_lock);
 562         return 0;
 563
 564 err_unreg:
 565         v4l2_device_disconnect(&mdev->v4l2_dev);
 566         v4l2_device_put(&mdev->v4l2_dev);
 567         return ret;
 568 }
 569
 570 static int aim_disconnect_channel(struct most_interface *iface,
 571                                   int channel_idx)
 572 {
 573         struct most_video_dev *mdev = get_aim_dev(iface, channel_idx);
 574
 575         pr_info("aim_disconnect_channel()\n");
 576
 577         if (!mdev) {
 578                 pr_err("no such channel is linked\n");
 579                 return -ENOENT;
 580         }
 581
 582         spin_lock(&list_lock);
 583         list_del(&mdev->list);
 584         spin_unlock(&list_lock);
 585
 586         aim_unregister_videodev(mdev);
 587         v4l2_device_disconnect(&mdev->v4l2_dev);
 588         v4l2_device_put(&mdev->v4l2_dev);
 589         return 0;
 590 }
 591
 592 static struct most_aim aim_info = {
 593         .name = "v4l",
 594         .probe_channel = aim_probe_channel,
 595         .disconnect_channel = aim_disconnect_channel,
 596         .rx_completion = aim_rx_data,
 597 };
 598
 599 static int __init aim_init(void)
 600 {
 601         spin_lock_init(&list_lock);
 602         return most_register_aim(&aim_info);
 603 }
 604
 605 static void __exit aim_exit(void)
 606 {
 607         struct most_video_dev *mdev, *tmp;
 608
 609         /*
 610          * As the mostcore currently doesn't call disconnect_channel()
 611          * for linked channels while we call most_deregister_aim()
 612          * we simulate this call here.
 613          * This must be fixed in core.
 614          */
 615         spin_lock(&list_lock);
 616         list_for_each_entry_safe(mdev, tmp, &video_devices, list) {
 617                 list_del(&mdev->list);
 618                 spin_unlock(&list_lock);
 619
 620                 aim_unregister_videodev(mdev);
 621                 v4l2_device_disconnect(&mdev->v4l2_dev);
 622                 v4l2_device_put(&mdev->v4l2_dev);
 623                 spin_lock(&list_lock);
 624         }
 625         spin_unlock(&list_lock);
 626
 627         most_deregister_aim(&aim_info);
 628         BUG_ON(!list_empty(&video_devices));
 629 }
 630
 631 module_init(aim_init);
 632 module_exit(aim_exit);
 633
 634 MODULE_DESCRIPTION("V4L2 Application Interface Module for MostCore");
 635 MODULE_AUTHOR("Andrey Shvetsov <andrey.shvetsov@k2l.de>");
 636 MODULE_LICENSE("GPL");