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