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