1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * video.c - V4L2 component for Mostcore 4 * 5 * Copyright (C) 2015, Microchip Technology Germany II GmbH & Co. KG 6 */ 7 8 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 9 10 #include <linux/module.h> 11 #include <linux/slab.h> 12 #include <linux/init.h> 13 #include <linux/device.h> 14 #include <linux/suspend.h> 15 #include <linux/videodev2.h> 16 #include <linux/mutex.h> 17 #include <media/v4l2-common.h> 18 #include <media/v4l2-ioctl.h> 19 #include <media/v4l2-event.h> 20 #include <media/v4l2-device.h> 21 #include <media/v4l2-ctrls.h> 22 #include <media/v4l2-fh.h> 23 #include <linux/most.h> 24 25 #define V4L2_CMP_MAX_INPUT 1 26 27 static struct most_component comp; 28 29 struct most_video_dev { 30 struct most_interface *iface; 31 int ch_idx; 32 struct list_head list; 33 bool mute; 34 35 struct list_head pending_mbos; 36 spinlock_t list_lock; 37 38 struct v4l2_device v4l2_dev; 39 atomic_t access_ref; 40 struct video_device *vdev; 41 unsigned int ctrl_input; 42 43 struct mutex lock; 44 45 wait_queue_head_t wait_data; 46 }; 47 48 struct comp_fh { 49 /* must be the first field of this struct! */ 50 struct v4l2_fh fh; 51 struct most_video_dev *mdev; 52 u32 offs; 53 }; 54 55 static LIST_HEAD(video_devices); 56 static DEFINE_SPINLOCK(list_lock); 57 58 static inline bool data_ready(struct most_video_dev *mdev) 59 { 60 return !list_empty(&mdev->pending_mbos); 61 } 62 63 static inline struct mbo *get_top_mbo(struct most_video_dev *mdev) 64 { 65 return list_first_entry(&mdev->pending_mbos, struct mbo, list); 66 } 67 68 static int comp_vdev_open(struct file *filp) 69 { 70 int ret; 71 struct video_device *vdev = video_devdata(filp); 72 struct most_video_dev *mdev = video_drvdata(filp); 73 struct comp_fh *fh; 74 75 switch (vdev->vfl_type) { 76 case VFL_TYPE_VIDEO: 77 break; 78 default: 79 return -EINVAL; 80 } 81 82 fh = kzalloc(sizeof(*fh), GFP_KERNEL); 83 if (!fh) 84 return -ENOMEM; 85 86 if (!atomic_inc_and_test(&mdev->access_ref)) { 87 v4l2_err(&mdev->v4l2_dev, "too many clients\n"); 88 ret = -EBUSY; 89 goto err_dec; 90 } 91 92 fh->mdev = mdev; 93 v4l2_fh_init(&fh->fh, vdev); 94 filp->private_data = fh; 95 96 v4l2_fh_add(&fh->fh); 97 98 ret = most_start_channel(mdev->iface, mdev->ch_idx, &comp); 99 if (ret) { 100 v4l2_err(&mdev->v4l2_dev, "most_start_channel() failed\n"); 101 goto err_rm; 102 } 103 104 return 0; 105 106 err_rm: 107 v4l2_fh_del(&fh->fh); 108 v4l2_fh_exit(&fh->fh); 109 110 err_dec: 111 atomic_dec(&mdev->access_ref); 112 kfree(fh); 113 return ret; 114 } 115 116 static int comp_vdev_close(struct file *filp) 117 { 118 struct comp_fh *fh = filp->private_data; 119 struct most_video_dev *mdev = fh->mdev; 120 struct mbo *mbo, *tmp; 121 122 /* 123 * We need to put MBOs back before we call most_stop_channel() 124 * to deallocate MBOs. 125 * From the other hand mostcore still calling rx_completion() 126 * to deliver MBOs until most_stop_channel() is called. 127 * Use mute to work around this issue. 128 * This must be implemented in core. 129 */ 130 131 spin_lock_irq(&mdev->list_lock); 132 mdev->mute = true; 133 list_for_each_entry_safe(mbo, tmp, &mdev->pending_mbos, list) { 134 list_del(&mbo->list); 135 spin_unlock_irq(&mdev->list_lock); 136 most_put_mbo(mbo); 137 spin_lock_irq(&mdev->list_lock); 138 } 139 spin_unlock_irq(&mdev->list_lock); 140 most_stop_channel(mdev->iface, mdev->ch_idx, &comp); 141 mdev->mute = false; 142 143 v4l2_fh_del(&fh->fh); 144 v4l2_fh_exit(&fh->fh); 145 146 atomic_dec(&mdev->access_ref); 147 kfree(fh); 148 return 0; 149 } 150 151 static ssize_t comp_vdev_read(struct file *filp, char __user *buf, 152 size_t count, loff_t *pos) 153 { 154 struct comp_fh *fh = filp->private_data; 155 struct most_video_dev *mdev = fh->mdev; 156 int ret = 0; 157 158 if (*pos) 159 return -ESPIPE; 160 161 if (!mdev) 162 return -ENODEV; 163 164 /* wait for the first buffer */ 165 if (!(filp->f_flags & O_NONBLOCK)) { 166 if (wait_event_interruptible(mdev->wait_data, data_ready(mdev))) 167 return -ERESTARTSYS; 168 } 169 170 if (!data_ready(mdev)) 171 return -EAGAIN; 172 173 while (count > 0 && data_ready(mdev)) { 174 struct mbo *const mbo = get_top_mbo(mdev); 175 int const rem = mbo->processed_length - fh->offs; 176 int const cnt = rem < count ? rem : count; 177 178 if (copy_to_user(buf, mbo->virt_address + fh->offs, cnt)) { 179 v4l2_err(&mdev->v4l2_dev, "read: copy_to_user failed\n"); 180 if (!ret) 181 ret = -EFAULT; 182 return ret; 183 } 184 185 fh->offs += cnt; 186 count -= cnt; 187 buf += cnt; 188 ret += cnt; 189 190 if (cnt >= rem) { 191 fh->offs = 0; 192 spin_lock_irq(&mdev->list_lock); 193 list_del(&mbo->list); 194 spin_unlock_irq(&mdev->list_lock); 195 most_put_mbo(mbo); 196 } 197 } 198 return ret; 199 } 200 201 static __poll_t comp_vdev_poll(struct file *filp, poll_table *wait) 202 { 203 struct comp_fh *fh = filp->private_data; 204 struct most_video_dev *mdev = fh->mdev; 205 __poll_t mask = 0; 206 207 /* only wait if no data is available */ 208 if (!data_ready(mdev)) 209 poll_wait(filp, &mdev->wait_data, wait); 210 if (data_ready(mdev)) 211 mask |= EPOLLIN | EPOLLRDNORM; 212 213 return mask; 214 } 215 216 static void comp_set_format_struct(struct v4l2_format *f) 217 { 218 f->fmt.pix.width = 8; 219 f->fmt.pix.height = 8; 220 f->fmt.pix.pixelformat = V4L2_PIX_FMT_MPEG; 221 f->fmt.pix.bytesperline = 0; 222 f->fmt.pix.sizeimage = 188 * 2; 223 f->fmt.pix.colorspace = V4L2_COLORSPACE_REC709; 224 f->fmt.pix.field = V4L2_FIELD_NONE; 225 f->fmt.pix.priv = 0; 226 } 227 228 static int comp_set_format(struct most_video_dev *mdev, unsigned int cmd, 229 struct v4l2_format *format) 230 { 231 if (format->fmt.pix.pixelformat != V4L2_PIX_FMT_MPEG) 232 return -EINVAL; 233 234 if (cmd == VIDIOC_TRY_FMT) 235 return 0; 236 237 comp_set_format_struct(format); 238 239 return 0; 240 } 241 242 static int vidioc_querycap(struct file *file, void *priv, 243 struct v4l2_capability *cap) 244 { 245 struct comp_fh *fh = priv; 246 struct most_video_dev *mdev = fh->mdev; 247 248 strscpy(cap->driver, "v4l2_component", sizeof(cap->driver)); 249 strscpy(cap->card, "MOST", sizeof(cap->card)); 250 snprintf(cap->bus_info, sizeof(cap->bus_info), 251 "%s", mdev->iface->description); 252 return 0; 253 } 254 255 static int vidioc_enum_fmt_vid_cap(struct file *file, void *priv, 256 struct v4l2_fmtdesc *f) 257 { 258 if (f->index) 259 return -EINVAL; 260 261 strscpy(f->description, "MPEG", sizeof(f->description)); 262 f->type = V4L2_BUF_TYPE_VIDEO_CAPTURE; 263 f->flags = V4L2_FMT_FLAG_COMPRESSED; 264 f->pixelformat = V4L2_PIX_FMT_MPEG; 265 266 return 0; 267 } 268 269 static int vidioc_g_fmt_vid_cap(struct file *file, void *priv, 270 struct v4l2_format *f) 271 { 272 comp_set_format_struct(f); 273 return 0; 274 } 275 276 static int vidioc_try_fmt_vid_cap(struct file *file, void *priv, 277 struct v4l2_format *f) 278 { 279 struct comp_fh *fh = priv; 280 struct most_video_dev *mdev = fh->mdev; 281 282 return comp_set_format(mdev, VIDIOC_TRY_FMT, f); 283 } 284 285 static int vidioc_s_fmt_vid_cap(struct file *file, void *priv, 286 struct v4l2_format *f) 287 { 288 struct comp_fh *fh = priv; 289 struct most_video_dev *mdev = fh->mdev; 290 291 return comp_set_format(mdev, VIDIOC_S_FMT, f); 292 } 293 294 static int vidioc_g_std(struct file *file, void *priv, v4l2_std_id *norm) 295 { 296 *norm = V4L2_STD_UNKNOWN; 297 return 0; 298 } 299 300 static int vidioc_enum_input(struct file *file, void *priv, 301 struct v4l2_input *input) 302 { 303 struct comp_fh *fh = priv; 304 struct most_video_dev *mdev = fh->mdev; 305 306 if (input->index >= V4L2_CMP_MAX_INPUT) 307 return -EINVAL; 308 309 strscpy(input->name, "MOST Video", sizeof(input->name)); 310 input->type |= V4L2_INPUT_TYPE_CAMERA; 311 input->audioset = 0; 312 313 input->std = mdev->vdev->tvnorms; 314 315 return 0; 316 } 317 318 static int vidioc_g_input(struct file *file, void *priv, unsigned int *i) 319 { 320 struct comp_fh *fh = priv; 321 struct most_video_dev *mdev = fh->mdev; 322 *i = mdev->ctrl_input; 323 return 0; 324 } 325 326 static int vidioc_s_input(struct file *file, void *priv, unsigned int index) 327 { 328 struct comp_fh *fh = priv; 329 struct most_video_dev *mdev = fh->mdev; 330 331 if (index >= V4L2_CMP_MAX_INPUT) 332 return -EINVAL; 333 mdev->ctrl_input = index; 334 return 0; 335 } 336 337 static const struct v4l2_file_operations comp_fops = { 338 .owner = THIS_MODULE, 339 .open = comp_vdev_open, 340 .release = comp_vdev_close, 341 .read = comp_vdev_read, 342 .poll = comp_vdev_poll, 343 .unlocked_ioctl = video_ioctl2, 344 }; 345 346 static const struct v4l2_ioctl_ops video_ioctl_ops = { 347 .vidioc_querycap = vidioc_querycap, 348 .vidioc_enum_fmt_vid_cap = vidioc_enum_fmt_vid_cap, 349 .vidioc_g_fmt_vid_cap = vidioc_g_fmt_vid_cap, 350 .vidioc_try_fmt_vid_cap = vidioc_try_fmt_vid_cap, 351 .vidioc_s_fmt_vid_cap = vidioc_s_fmt_vid_cap, 352 .vidioc_g_std = vidioc_g_std, 353 .vidioc_enum_input = vidioc_enum_input, 354 .vidioc_g_input = vidioc_g_input, 355 .vidioc_s_input = vidioc_s_input, 356 }; 357 358 static const struct video_device comp_videodev_template = { 359 .fops = &comp_fops, 360 .release = video_device_release, 361 .ioctl_ops = &video_ioctl_ops, 362 .tvnorms = V4L2_STD_UNKNOWN, 363 .device_caps = V4L2_CAP_READWRITE | V4L2_CAP_VIDEO_CAPTURE, 364 }; 365 366 /**************************************************************************/ 367 368 static struct most_video_dev *get_comp_dev(struct most_interface *iface, int channel_idx) 369 { 370 struct most_video_dev *mdev; 371 unsigned long flags; 372 373 spin_lock_irqsave(&list_lock, flags); 374 list_for_each_entry(mdev, &video_devices, list) { 375 if (mdev->iface == iface && mdev->ch_idx == channel_idx) { 376 spin_unlock_irqrestore(&list_lock, flags); 377 return mdev; 378 } 379 } 380 spin_unlock_irqrestore(&list_lock, flags); 381 return NULL; 382 } 383 384 static int comp_rx_data(struct mbo *mbo) 385 { 386 unsigned long flags; 387 struct most_video_dev *mdev = 388 get_comp_dev(mbo->ifp, mbo->hdm_channel_id); 389 390 if (!mdev) 391 return -EIO; 392 393 spin_lock_irqsave(&mdev->list_lock, flags); 394 if (unlikely(mdev->mute)) { 395 spin_unlock_irqrestore(&mdev->list_lock, flags); 396 return -EIO; 397 } 398 399 list_add_tail(&mbo->list, &mdev->pending_mbos); 400 spin_unlock_irqrestore(&mdev->list_lock, flags); 401 wake_up_interruptible(&mdev->wait_data); 402 return 0; 403 } 404 405 static int comp_register_videodev(struct most_video_dev *mdev) 406 { 407 int ret; 408 409 init_waitqueue_head(&mdev->wait_data); 410 411 /* allocate and fill v4l2 video struct */ 412 mdev->vdev = video_device_alloc(); 413 if (!mdev->vdev) 414 return -ENOMEM; 415 416 /* Fill the video capture device struct */ 417 *mdev->vdev = comp_videodev_template; 418 mdev->vdev->v4l2_dev = &mdev->v4l2_dev; 419 mdev->vdev->lock = &mdev->lock; 420 snprintf(mdev->vdev->name, sizeof(mdev->vdev->name), "MOST: %s", 421 mdev->v4l2_dev.name); 422 423 /* Register the v4l2 device */ 424 video_set_drvdata(mdev->vdev, mdev); 425 ret = video_register_device(mdev->vdev, VFL_TYPE_VIDEO, -1); 426 if (ret) { 427 v4l2_err(&mdev->v4l2_dev, "video_register_device failed (%d)\n", 428 ret); 429 video_device_release(mdev->vdev); 430 } 431 432 return ret; 433 } 434 435 static void comp_unregister_videodev(struct most_video_dev *mdev) 436 { 437 video_unregister_device(mdev->vdev); 438 } 439 440 static void comp_v4l2_dev_release(struct v4l2_device *v4l2_dev) 441 { 442 struct most_video_dev *mdev = 443 container_of(v4l2_dev, struct most_video_dev, v4l2_dev); 444 445 v4l2_device_unregister(v4l2_dev); 446 kfree(mdev); 447 } 448 449 static int comp_probe_channel(struct most_interface *iface, int channel_idx, 450 struct most_channel_config *ccfg, char *name, 451 char *args) 452 { 453 int ret; 454 struct most_video_dev *mdev = get_comp_dev(iface, channel_idx); 455 456 if (mdev) { 457 pr_err("channel already linked\n"); 458 return -EEXIST; 459 } 460 461 if (ccfg->direction != MOST_CH_RX) { 462 pr_err("wrong direction, expect rx\n"); 463 return -EINVAL; 464 } 465 466 if (ccfg->data_type != MOST_CH_SYNC && 467 ccfg->data_type != MOST_CH_ISOC) { 468 pr_err("wrong channel type, expect sync or isoc\n"); 469 return -EINVAL; 470 } 471 472 mdev = kzalloc(sizeof(*mdev), GFP_KERNEL); 473 if (!mdev) 474 return -ENOMEM; 475 476 mutex_init(&mdev->lock); 477 atomic_set(&mdev->access_ref, -1); 478 spin_lock_init(&mdev->list_lock); 479 INIT_LIST_HEAD(&mdev->pending_mbos); 480 mdev->iface = iface; 481 mdev->ch_idx = channel_idx; 482 mdev->v4l2_dev.release = comp_v4l2_dev_release; 483 484 /* Create the v4l2_device */ 485 strscpy(mdev->v4l2_dev.name, name, sizeof(mdev->v4l2_dev.name)); 486 ret = v4l2_device_register(NULL, &mdev->v4l2_dev); 487 if (ret) { 488 pr_err("v4l2_device_register() failed\n"); 489 kfree(mdev); 490 return ret; 491 } 492 493 ret = comp_register_videodev(mdev); 494 if (ret) 495 goto err_unreg; 496 497 spin_lock_irq(&list_lock); 498 list_add(&mdev->list, &video_devices); 499 spin_unlock_irq(&list_lock); 500 return 0; 501 502 err_unreg: 503 v4l2_device_disconnect(&mdev->v4l2_dev); 504 v4l2_device_put(&mdev->v4l2_dev); 505 return ret; 506 } 507 508 static int comp_disconnect_channel(struct most_interface *iface, 509 int channel_idx) 510 { 511 struct most_video_dev *mdev = get_comp_dev(iface, channel_idx); 512 513 if (!mdev) { 514 pr_err("no such channel is linked\n"); 515 return -ENOENT; 516 } 517 518 spin_lock_irq(&list_lock); 519 list_del(&mdev->list); 520 spin_unlock_irq(&list_lock); 521 522 comp_unregister_videodev(mdev); 523 v4l2_device_disconnect(&mdev->v4l2_dev); 524 v4l2_device_put(&mdev->v4l2_dev); 525 return 0; 526 } 527 528 static struct most_component comp = { 529 .mod = THIS_MODULE, 530 .name = "video", 531 .probe_channel = comp_probe_channel, 532 .disconnect_channel = comp_disconnect_channel, 533 .rx_completion = comp_rx_data, 534 }; 535 536 static int __init comp_init(void) 537 { 538 int err; 539 540 err = most_register_component(&comp); 541 if (err) 542 return err; 543 err = most_register_configfs_subsys(&comp); 544 if (err) { 545 most_deregister_component(&comp); 546 return err; 547 } 548 return 0; 549 } 550 551 static void __exit comp_exit(void) 552 { 553 struct most_video_dev *mdev, *tmp; 554 555 /* 556 * As the mostcore currently doesn't call disconnect_channel() 557 * for linked channels while we call most_deregister_component() 558 * we simulate this call here. 559 * This must be fixed in core. 560 */ 561 spin_lock_irq(&list_lock); 562 list_for_each_entry_safe(mdev, tmp, &video_devices, list) { 563 list_del(&mdev->list); 564 spin_unlock_irq(&list_lock); 565 566 comp_unregister_videodev(mdev); 567 v4l2_device_disconnect(&mdev->v4l2_dev); 568 v4l2_device_put(&mdev->v4l2_dev); 569 spin_lock_irq(&list_lock); 570 } 571 spin_unlock_irq(&list_lock); 572 573 most_deregister_configfs_subsys(&comp); 574 most_deregister_component(&comp); 575 BUG_ON(!list_empty(&video_devices)); 576 } 577 578 module_init(comp_init); 579 module_exit(comp_exit); 580 581 MODULE_DESCRIPTION("V4L2 Component Module for Mostcore"); 582 MODULE_AUTHOR("Andrey Shvetsov <andrey.shvetsov@k2l.de>"); 583 MODULE_LICENSE("GPL"); 584