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 24 #include "most/core.h" 25 26 #define V4L2_CMP_MAX_INPUT 1 27 28 static struct core_component comp; 29 30 struct most_video_dev { 31 struct most_interface *iface; 32 int ch_idx; 33 struct list_head list; 34 bool mute; 35 36 struct list_head pending_mbos; 37 spinlock_t list_lock; 38 39 struct v4l2_device v4l2_dev; 40 atomic_t access_ref; 41 struct video_device *vdev; 42 unsigned int ctrl_input; 43 44 struct mutex lock; 45 46 wait_queue_head_t wait_data; 47 }; 48 49 struct comp_fh { 50 /* must be the first field of this struct! */ 51 struct v4l2_fh fh; 52 struct most_video_dev *mdev; 53 u32 offs; 54 }; 55 56 static struct list_head video_devices = LIST_HEAD_INIT(video_devices); 57 static struct spinlock list_lock; 58 59 static inline bool data_ready(struct most_video_dev *mdev) 60 { 61 return !list_empty(&mdev->pending_mbos); 62 } 63 64 static inline struct mbo *get_top_mbo(struct most_video_dev *mdev) 65 { 66 return list_first_entry(&mdev->pending_mbos, struct mbo, list); 67 } 68 69 static int comp_vdev_open(struct file *filp) 70 { 71 int ret; 72 struct video_device *vdev = video_devdata(filp); 73 struct most_video_dev *mdev = video_drvdata(filp); 74 struct comp_fh *fh; 75 76 switch (vdev->vfl_type) { 77 case VFL_TYPE_GRABBER: 78 break; 79 default: 80 return -EINVAL; 81 } 82 83 fh = kzalloc(sizeof(*fh), GFP_KERNEL); 84 if (!fh) 85 return -ENOMEM; 86 87 if (!atomic_inc_and_test(&mdev->access_ref)) { 88 v4l2_err(&mdev->v4l2_dev, "too many clients\n"); 89 ret = -EBUSY; 90 goto err_dec; 91 } 92 93 fh->mdev = mdev; 94 v4l2_fh_init(&fh->fh, vdev); 95 filp->private_data = fh; 96 97 v4l2_fh_add(&fh->fh); 98 99 ret = most_start_channel(mdev->iface, mdev->ch_idx, &comp); 100 if (ret) { 101 v4l2_err(&mdev->v4l2_dev, "most_start_channel() failed\n"); 102 goto err_rm; 103 } 104 105 return 0; 106 107 err_rm: 108 v4l2_fh_del(&fh->fh); 109 v4l2_fh_exit(&fh->fh); 110 111 err_dec: 112 atomic_dec(&mdev->access_ref); 113 kfree(fh); 114 return ret; 115 } 116 117 static int comp_vdev_close(struct file *filp) 118 { 119 struct comp_fh *fh = filp->private_data; 120 struct most_video_dev *mdev = fh->mdev; 121 struct mbo *mbo, *tmp; 122 123 /* 124 * We need to put MBOs back before we call most_stop_channel() 125 * to deallocate MBOs. 126 * From the other hand mostcore still calling rx_completion() 127 * to deliver MBOs until most_stop_channel() is called. 128 * Use mute to work around this issue. 129 * This must be implemented in core. 130 */ 131 132 spin_lock_irq(&mdev->list_lock); 133 mdev->mute = true; 134 list_for_each_entry_safe(mbo, tmp, &mdev->pending_mbos, list) { 135 list_del(&mbo->list); 136 spin_unlock_irq(&mdev->list_lock); 137 most_put_mbo(mbo); 138 spin_lock_irq(&mdev->list_lock); 139 } 140 spin_unlock_irq(&mdev->list_lock); 141 most_stop_channel(mdev->iface, mdev->ch_idx, &comp); 142 mdev->mute = false; 143 144 v4l2_fh_del(&fh->fh); 145 v4l2_fh_exit(&fh->fh); 146 147 atomic_dec(&mdev->access_ref); 148 kfree(fh); 149 return 0; 150 } 151 152 static ssize_t comp_vdev_read(struct file *filp, char __user *buf, 153 size_t count, loff_t *pos) 154 { 155 struct comp_fh *fh = filp->private_data; 156 struct most_video_dev *mdev = fh->mdev; 157 int ret = 0; 158 159 if (*pos) 160 return -ESPIPE; 161 162 if (!mdev) 163 return -ENODEV; 164 165 /* wait for the first buffer */ 166 if (!(filp->f_flags & O_NONBLOCK)) { 167 if (wait_event_interruptible(mdev->wait_data, data_ready(mdev))) 168 return -ERESTARTSYS; 169 } 170 171 if (!data_ready(mdev)) 172 return -EAGAIN; 173 174 while (count > 0 && data_ready(mdev)) { 175 struct mbo *const mbo = get_top_mbo(mdev); 176 int const rem = mbo->processed_length - fh->offs; 177 int const cnt = rem < count ? rem : count; 178 179 if (copy_to_user(buf, mbo->virt_address + fh->offs, cnt)) { 180 v4l2_err(&mdev->v4l2_dev, "read: copy_to_user failed\n"); 181 if (!ret) 182 ret = -EFAULT; 183 return ret; 184 } 185 186 fh->offs += cnt; 187 count -= cnt; 188 buf += cnt; 189 ret += cnt; 190 191 if (cnt >= rem) { 192 fh->offs = 0; 193 spin_lock_irq(&mdev->list_lock); 194 list_del(&mbo->list); 195 spin_unlock_irq(&mdev->list_lock); 196 most_put_mbo(mbo); 197 } 198 } 199 return ret; 200 } 201 202 static __poll_t comp_vdev_poll(struct file *filp, poll_table *wait) 203 { 204 struct comp_fh *fh = filp->private_data; 205 struct most_video_dev *mdev = fh->mdev; 206 __poll_t mask = 0; 207 208 /* only wait if no data is available */ 209 if (!data_ready(mdev)) 210 poll_wait(filp, &mdev->wait_data, wait); 211 if (data_ready(mdev)) 212 mask |= EPOLLIN | EPOLLRDNORM; 213 214 return mask; 215 } 216 217 static void comp_set_format_struct(struct v4l2_format *f) 218 { 219 f->fmt.pix.width = 8; 220 f->fmt.pix.height = 8; 221 f->fmt.pix.pixelformat = V4L2_PIX_FMT_MPEG; 222 f->fmt.pix.bytesperline = 0; 223 f->fmt.pix.sizeimage = 188 * 2; 224 f->fmt.pix.colorspace = V4L2_COLORSPACE_REC709; 225 f->fmt.pix.field = V4L2_FIELD_NONE; 226 f->fmt.pix.priv = 0; 227 } 228 229 static int comp_set_format(struct most_video_dev *mdev, unsigned int cmd, 230 struct v4l2_format *format) 231 { 232 if (format->fmt.pix.pixelformat != V4L2_PIX_FMT_MPEG) 233 return -EINVAL; 234 235 if (cmd == VIDIOC_TRY_FMT) 236 return 0; 237 238 comp_set_format_struct(format); 239 240 return 0; 241 } 242 243 static int vidioc_querycap(struct file *file, void *priv, 244 struct v4l2_capability *cap) 245 { 246 struct comp_fh *fh = priv; 247 struct most_video_dev *mdev = fh->mdev; 248 249 strlcpy(cap->driver, "v4l2_component", sizeof(cap->driver)); 250 strlcpy(cap->card, "MOST", sizeof(cap->card)); 251 snprintf(cap->bus_info, sizeof(cap->bus_info), 252 "%s", mdev->iface->description); 253 254 cap->capabilities = 255 V4L2_CAP_READWRITE | 256 V4L2_CAP_TUNER | 257 V4L2_CAP_VIDEO_CAPTURE; 258 return 0; 259 } 260 261 static int vidioc_enum_fmt_vid_cap(struct file *file, void *priv, 262 struct v4l2_fmtdesc *f) 263 { 264 if (f->index) 265 return -EINVAL; 266 267 strcpy(f->description, "MPEG"); 268 f->type = V4L2_BUF_TYPE_VIDEO_CAPTURE; 269 f->flags = V4L2_FMT_FLAG_COMPRESSED; 270 f->pixelformat = V4L2_PIX_FMT_MPEG; 271 272 return 0; 273 } 274 275 static int vidioc_g_fmt_vid_cap(struct file *file, void *priv, 276 struct v4l2_format *f) 277 { 278 comp_set_format_struct(f); 279 return 0; 280 } 281 282 static int vidioc_try_fmt_vid_cap(struct file *file, void *priv, 283 struct v4l2_format *f) 284 { 285 struct comp_fh *fh = priv; 286 struct most_video_dev *mdev = fh->mdev; 287 288 return comp_set_format(mdev, VIDIOC_TRY_FMT, f); 289 } 290 291 static int vidioc_s_fmt_vid_cap(struct file *file, void *priv, 292 struct v4l2_format *f) 293 { 294 struct comp_fh *fh = priv; 295 struct most_video_dev *mdev = fh->mdev; 296 297 return comp_set_format(mdev, VIDIOC_S_FMT, f); 298 } 299 300 static int vidioc_g_std(struct file *file, void *priv, v4l2_std_id *norm) 301 { 302 *norm = V4L2_STD_UNKNOWN; 303 return 0; 304 } 305 306 static int vidioc_enum_input(struct file *file, void *priv, 307 struct v4l2_input *input) 308 { 309 struct comp_fh *fh = priv; 310 struct most_video_dev *mdev = fh->mdev; 311 312 if (input->index >= V4L2_CMP_MAX_INPUT) 313 return -EINVAL; 314 315 strcpy(input->name, "MOST Video"); 316 input->type |= V4L2_INPUT_TYPE_CAMERA; 317 input->audioset = 0; 318 319 input->std = mdev->vdev->tvnorms; 320 321 return 0; 322 } 323 324 static int vidioc_g_input(struct file *file, void *priv, unsigned int *i) 325 { 326 struct comp_fh *fh = priv; 327 struct most_video_dev *mdev = fh->mdev; 328 *i = mdev->ctrl_input; 329 return 0; 330 } 331 332 static int vidioc_s_input(struct file *file, void *priv, unsigned int index) 333 { 334 struct comp_fh *fh = priv; 335 struct most_video_dev *mdev = fh->mdev; 336 337 if (index >= V4L2_CMP_MAX_INPUT) 338 return -EINVAL; 339 mdev->ctrl_input = index; 340 return 0; 341 } 342 343 static const struct v4l2_file_operations comp_fops = { 344 .owner = THIS_MODULE, 345 .open = comp_vdev_open, 346 .release = comp_vdev_close, 347 .read = comp_vdev_read, 348 .poll = comp_vdev_poll, 349 .unlocked_ioctl = video_ioctl2, 350 }; 351 352 static const struct v4l2_ioctl_ops video_ioctl_ops = { 353 .vidioc_querycap = vidioc_querycap, 354 .vidioc_enum_fmt_vid_cap = vidioc_enum_fmt_vid_cap, 355 .vidioc_g_fmt_vid_cap = vidioc_g_fmt_vid_cap, 356 .vidioc_try_fmt_vid_cap = vidioc_try_fmt_vid_cap, 357 .vidioc_s_fmt_vid_cap = vidioc_s_fmt_vid_cap, 358 .vidioc_g_std = vidioc_g_std, 359 .vidioc_enum_input = vidioc_enum_input, 360 .vidioc_g_input = vidioc_g_input, 361 .vidioc_s_input = vidioc_s_input, 362 }; 363 364 static const struct video_device comp_videodev_template = { 365 .fops = &comp_fops, 366 .release = video_device_release, 367 .ioctl_ops = &video_ioctl_ops, 368 .tvnorms = V4L2_STD_UNKNOWN, 369 }; 370 371 /**************************************************************************/ 372 373 static struct most_video_dev *get_comp_dev( 374 struct most_interface *iface, int channel_idx) 375 { 376 struct most_video_dev *mdev; 377 unsigned long flags; 378 379 spin_lock_irqsave(&list_lock, flags); 380 list_for_each_entry(mdev, &video_devices, list) { 381 if (mdev->iface == iface && mdev->ch_idx == channel_idx) { 382 spin_unlock_irqrestore(&list_lock, flags); 383 return mdev; 384 } 385 } 386 spin_unlock_irqrestore(&list_lock, flags); 387 return NULL; 388 } 389 390 static int comp_rx_data(struct mbo *mbo) 391 { 392 unsigned long flags; 393 struct most_video_dev *mdev = 394 get_comp_dev(mbo->ifp, mbo->hdm_channel_id); 395 396 if (!mdev) 397 return -EIO; 398 399 spin_lock_irqsave(&mdev->list_lock, flags); 400 if (unlikely(mdev->mute)) { 401 spin_unlock_irqrestore(&mdev->list_lock, flags); 402 return -EIO; 403 } 404 405 list_add_tail(&mbo->list, &mdev->pending_mbos); 406 spin_unlock_irqrestore(&mdev->list_lock, flags); 407 wake_up_interruptible(&mdev->wait_data); 408 return 0; 409 } 410 411 static int comp_register_videodev(struct most_video_dev *mdev) 412 { 413 int ret; 414 415 init_waitqueue_head(&mdev->wait_data); 416 417 /* allocate and fill v4l2 video struct */ 418 mdev->vdev = video_device_alloc(); 419 if (!mdev->vdev) 420 return -ENOMEM; 421 422 /* Fill the video capture device struct */ 423 *mdev->vdev = comp_videodev_template; 424 mdev->vdev->v4l2_dev = &mdev->v4l2_dev; 425 mdev->vdev->lock = &mdev->lock; 426 snprintf(mdev->vdev->name, sizeof(mdev->vdev->name), "MOST: %s", 427 mdev->v4l2_dev.name); 428 429 /* Register the v4l2 device */ 430 video_set_drvdata(mdev->vdev, mdev); 431 ret = video_register_device(mdev->vdev, VFL_TYPE_GRABBER, -1); 432 if (ret) { 433 v4l2_err(&mdev->v4l2_dev, "video_register_device failed (%d)\n", 434 ret); 435 video_device_release(mdev->vdev); 436 } 437 438 return ret; 439 } 440 441 static void comp_unregister_videodev(struct most_video_dev *mdev) 442 { 443 video_unregister_device(mdev->vdev); 444 } 445 446 static void comp_v4l2_dev_release(struct v4l2_device *v4l2_dev) 447 { 448 struct most_video_dev *mdev = 449 container_of(v4l2_dev, struct most_video_dev, v4l2_dev); 450 451 v4l2_device_unregister(v4l2_dev); 452 kfree(mdev); 453 } 454 455 static int comp_probe_channel(struct most_interface *iface, int channel_idx, 456 struct most_channel_config *ccfg, char *name) 457 { 458 int ret; 459 struct most_video_dev *mdev = get_comp_dev(iface, channel_idx); 460 461 if (mdev) { 462 pr_err("channel already linked\n"); 463 return -EEXIST; 464 } 465 466 if (ccfg->direction != MOST_CH_RX) { 467 pr_err("wrong direction, expect rx\n"); 468 return -EINVAL; 469 } 470 471 if (ccfg->data_type != MOST_CH_SYNC && 472 ccfg->data_type != MOST_CH_ISOC) { 473 pr_err("wrong channel type, expect sync or isoc\n"); 474 return -EINVAL; 475 } 476 477 mdev = kzalloc(sizeof(*mdev), GFP_KERNEL); 478 if (!mdev) 479 return -ENOMEM; 480 481 mutex_init(&mdev->lock); 482 atomic_set(&mdev->access_ref, -1); 483 spin_lock_init(&mdev->list_lock); 484 INIT_LIST_HEAD(&mdev->pending_mbos); 485 mdev->iface = iface; 486 mdev->ch_idx = channel_idx; 487 mdev->v4l2_dev.release = comp_v4l2_dev_release; 488 489 /* Create the v4l2_device */ 490 strlcpy(mdev->v4l2_dev.name, name, sizeof(mdev->v4l2_dev.name)); 491 ret = v4l2_device_register(NULL, &mdev->v4l2_dev); 492 if (ret) { 493 pr_err("v4l2_device_register() failed\n"); 494 kfree(mdev); 495 return ret; 496 } 497 498 ret = comp_register_videodev(mdev); 499 if (ret) 500 goto err_unreg; 501 502 spin_lock_irq(&list_lock); 503 list_add(&mdev->list, &video_devices); 504 spin_unlock_irq(&list_lock); 505 return 0; 506 507 err_unreg: 508 v4l2_device_disconnect(&mdev->v4l2_dev); 509 v4l2_device_put(&mdev->v4l2_dev); 510 return ret; 511 } 512 513 static int comp_disconnect_channel(struct most_interface *iface, 514 int channel_idx) 515 { 516 struct most_video_dev *mdev = get_comp_dev(iface, channel_idx); 517 518 if (!mdev) { 519 pr_err("no such channel is linked\n"); 520 return -ENOENT; 521 } 522 523 spin_lock_irq(&list_lock); 524 list_del(&mdev->list); 525 spin_unlock_irq(&list_lock); 526 527 comp_unregister_videodev(mdev); 528 v4l2_device_disconnect(&mdev->v4l2_dev); 529 v4l2_device_put(&mdev->v4l2_dev); 530 return 0; 531 } 532 533 static struct core_component comp = { 534 .name = "video", 535 .probe_channel = comp_probe_channel, 536 .disconnect_channel = comp_disconnect_channel, 537 .rx_completion = comp_rx_data, 538 }; 539 540 static int __init comp_init(void) 541 { 542 spin_lock_init(&list_lock); 543 return most_register_component(&comp); 544 } 545 546 static void __exit comp_exit(void) 547 { 548 struct most_video_dev *mdev, *tmp; 549 550 /* 551 * As the mostcore currently doesn't call disconnect_channel() 552 * for linked channels while we call most_deregister_component() 553 * we simulate this call here. 554 * This must be fixed in core. 555 */ 556 spin_lock_irq(&list_lock); 557 list_for_each_entry_safe(mdev, tmp, &video_devices, list) { 558 list_del(&mdev->list); 559 spin_unlock_irq(&list_lock); 560 561 comp_unregister_videodev(mdev); 562 v4l2_device_disconnect(&mdev->v4l2_dev); 563 v4l2_device_put(&mdev->v4l2_dev); 564 spin_lock_irq(&list_lock); 565 } 566 spin_unlock_irq(&list_lock); 567 568 most_deregister_component(&comp); 569 BUG_ON(!list_empty(&video_devices)); 570 } 571 572 module_init(comp_init); 573 module_exit(comp_exit); 574 575 MODULE_DESCRIPTION("V4L2 Component Module for Mostcore"); 576 MODULE_AUTHOR("Andrey Shvetsov <andrey.shvetsov@k2l.de>"); 577 MODULE_LICENSE("GPL"); 578