1 /* 2 * This is a V4L2 PCI Skeleton Driver. It gives an initial skeleton source 3 * for use with other PCI drivers. 4 * 5 * This skeleton PCI driver assumes that the card has an S-Video connector as 6 * input 0 and an HDMI connector as input 1. 7 * 8 * Copyright 2014 Cisco Systems, Inc. and/or its affiliates. All rights reserved. 9 * 10 * This program is free software; you may redistribute it and/or modify 11 * it under the terms of the GNU General Public License as published by 12 * the Free Software Foundation; version 2 of the License. 13 * 14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 15 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 16 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 17 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS 18 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN 19 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 20 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 21 * SOFTWARE. 22 */ 23 24 #include <linux/types.h> 25 #include <linux/kernel.h> 26 #include <linux/module.h> 27 #include <linux/init.h> 28 #include <linux/kmod.h> 29 #include <linux/mutex.h> 30 #include <linux/pci.h> 31 #include <linux/interrupt.h> 32 #include <linux/videodev2.h> 33 #include <linux/v4l2-dv-timings.h> 34 #include <media/v4l2-device.h> 35 #include <media/v4l2-dev.h> 36 #include <media/v4l2-ioctl.h> 37 #include <media/v4l2-dv-timings.h> 38 #include <media/v4l2-ctrls.h> 39 #include <media/v4l2-event.h> 40 #include <media/videobuf2-v4l2.h> 41 #include <media/videobuf2-dma-contig.h> 42 43 MODULE_DESCRIPTION("V4L2 PCI Skeleton Driver"); 44 MODULE_AUTHOR("Hans Verkuil"); 45 MODULE_LICENSE("GPL v2"); 46 47 /** 48 * struct skeleton - All internal data for one instance of device 49 * @pdev: PCI device 50 * @v4l2_dev: top-level v4l2 device struct 51 * @vdev: video node structure 52 * @ctrl_handler: control handler structure 53 * @lock: ioctl serialization mutex 54 * @std: current SDTV standard 55 * @timings: current HDTV timings 56 * @format: current pix format 57 * @input: current video input (0 = SDTV, 1 = HDTV) 58 * @queue: vb2 video capture queue 59 * @qlock: spinlock controlling access to buf_list and sequence 60 * @buf_list: list of buffers queued for DMA 61 * @field: the field (TOP/BOTTOM/other) of the current buffer 62 * @sequence: frame sequence counter 63 */ 64 struct skeleton { 65 struct pci_dev *pdev; 66 struct v4l2_device v4l2_dev; 67 struct video_device vdev; 68 struct v4l2_ctrl_handler ctrl_handler; 69 struct mutex lock; 70 v4l2_std_id std; 71 struct v4l2_dv_timings timings; 72 struct v4l2_pix_format format; 73 unsigned input; 74 75 struct vb2_queue queue; 76 77 spinlock_t qlock; 78 struct list_head buf_list; 79 unsigned field; 80 unsigned sequence; 81 }; 82 83 struct skel_buffer { 84 struct vb2_v4l2_buffer vb; 85 struct list_head list; 86 }; 87 88 static inline struct skel_buffer *to_skel_buffer(struct vb2_v4l2_buffer *vbuf) 89 { 90 return container_of(vbuf, struct skel_buffer, vb); 91 } 92 93 static const struct pci_device_id skeleton_pci_tbl[] = { 94 /* { PCI_DEVICE(PCI_VENDOR_ID_, PCI_DEVICE_ID_) }, */ 95 { 0, } 96 }; 97 MODULE_DEVICE_TABLE(pci, skeleton_pci_tbl); 98 99 /* 100 * HDTV: this structure has the capabilities of the HDTV receiver. 101 * It is used to constrain the huge list of possible formats based 102 * upon the hardware capabilities. 103 */ 104 static const struct v4l2_dv_timings_cap skel_timings_cap = { 105 .type = V4L2_DV_BT_656_1120, 106 /* keep this initialization for compatibility with GCC < 4.4.6 */ 107 .reserved = { 0 }, 108 V4L2_INIT_BT_TIMINGS( 109 720, 1920, /* min/max width */ 110 480, 1080, /* min/max height */ 111 27000000, 74250000, /* min/max pixelclock*/ 112 V4L2_DV_BT_STD_CEA861, /* Supported standards */ 113 /* capabilities */ 114 V4L2_DV_BT_CAP_INTERLACED | V4L2_DV_BT_CAP_PROGRESSIVE 115 ) 116 }; 117 118 /* 119 * Supported SDTV standards. This does the same job as skel_timings_cap, but 120 * for standard TV formats. 121 */ 122 #define SKEL_TVNORMS V4L2_STD_ALL 123 124 /* 125 * Interrupt handler: typically interrupts happen after a new frame has been 126 * captured. It is the job of the handler to remove the new frame from the 127 * internal list and give it back to the vb2 framework, updating the sequence 128 * counter, field and timestamp at the same time. 129 */ 130 static irqreturn_t skeleton_irq(int irq, void *dev_id) 131 { 132 #ifdef TODO 133 struct skeleton *skel = dev_id; 134 135 /* handle interrupt */ 136 137 /* Once a new frame has been captured, mark it as done like this: */ 138 if (captured_new_frame) { 139 ... 140 spin_lock(&skel->qlock); 141 list_del(&new_buf->list); 142 spin_unlock(&skel->qlock); 143 new_buf->vb.vb2_buf.timestamp = ktime_get_ns(); 144 new_buf->vb.sequence = skel->sequence++; 145 new_buf->vb.field = skel->field; 146 if (skel->format.field == V4L2_FIELD_ALTERNATE) { 147 if (skel->field == V4L2_FIELD_BOTTOM) 148 skel->field = V4L2_FIELD_TOP; 149 else if (skel->field == V4L2_FIELD_TOP) 150 skel->field = V4L2_FIELD_BOTTOM; 151 } 152 vb2_buffer_done(&new_buf->vb.vb2_buf, VB2_BUF_STATE_DONE); 153 } 154 #endif 155 return IRQ_HANDLED; 156 } 157 158 /* 159 * Setup the constraints of the queue: besides setting the number of planes 160 * per buffer and the size and allocation context of each plane, it also 161 * checks if sufficient buffers have been allocated. Usually 3 is a good 162 * minimum number: many DMA engines need a minimum of 2 buffers in the 163 * queue and you need to have another available for userspace processing. 164 */ 165 static int queue_setup(struct vb2_queue *vq, 166 unsigned int *nbuffers, unsigned int *nplanes, 167 unsigned int sizes[], struct device *alloc_devs[]) 168 { 169 struct skeleton *skel = vb2_get_drv_priv(vq); 170 171 skel->field = skel->format.field; 172 if (skel->field == V4L2_FIELD_ALTERNATE) { 173 /* 174 * You cannot use read() with FIELD_ALTERNATE since the field 175 * information (TOP/BOTTOM) cannot be passed back to the user. 176 */ 177 if (vb2_fileio_is_active(vq)) 178 return -EINVAL; 179 skel->field = V4L2_FIELD_TOP; 180 } 181 182 if (vq->num_buffers + *nbuffers < 3) 183 *nbuffers = 3 - vq->num_buffers; 184 185 if (*nplanes) 186 return sizes[0] < skel->format.sizeimage ? -EINVAL : 0; 187 *nplanes = 1; 188 sizes[0] = skel->format.sizeimage; 189 return 0; 190 } 191 192 /* 193 * Prepare the buffer for queueing to the DMA engine: check and set the 194 * payload size. 195 */ 196 static int buffer_prepare(struct vb2_buffer *vb) 197 { 198 struct skeleton *skel = vb2_get_drv_priv(vb->vb2_queue); 199 unsigned long size = skel->format.sizeimage; 200 201 if (vb2_plane_size(vb, 0) < size) { 202 dev_err(&skel->pdev->dev, "buffer too small (%lu < %lu)\n", 203 vb2_plane_size(vb, 0), size); 204 return -EINVAL; 205 } 206 207 vb2_set_plane_payload(vb, 0, size); 208 return 0; 209 } 210 211 /* 212 * Queue this buffer to the DMA engine. 213 */ 214 static void buffer_queue(struct vb2_buffer *vb) 215 { 216 struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb); 217 struct skeleton *skel = vb2_get_drv_priv(vb->vb2_queue); 218 struct skel_buffer *buf = to_skel_buffer(vbuf); 219 unsigned long flags; 220 221 spin_lock_irqsave(&skel->qlock, flags); 222 list_add_tail(&buf->list, &skel->buf_list); 223 224 /* TODO: Update any DMA pointers if necessary */ 225 226 spin_unlock_irqrestore(&skel->qlock, flags); 227 } 228 229 static void return_all_buffers(struct skeleton *skel, 230 enum vb2_buffer_state state) 231 { 232 struct skel_buffer *buf, *node; 233 unsigned long flags; 234 235 spin_lock_irqsave(&skel->qlock, flags); 236 list_for_each_entry_safe(buf, node, &skel->buf_list, list) { 237 vb2_buffer_done(&buf->vb.vb2_buf, state); 238 list_del(&buf->list); 239 } 240 spin_unlock_irqrestore(&skel->qlock, flags); 241 } 242 243 /* 244 * Start streaming. First check if the minimum number of buffers have been 245 * queued. If not, then return -ENOBUFS and the vb2 framework will call 246 * this function again the next time a buffer has been queued until enough 247 * buffers are available to actually start the DMA engine. 248 */ 249 static int start_streaming(struct vb2_queue *vq, unsigned int count) 250 { 251 struct skeleton *skel = vb2_get_drv_priv(vq); 252 int ret = 0; 253 254 skel->sequence = 0; 255 256 /* TODO: start DMA */ 257 258 if (ret) { 259 /* 260 * In case of an error, return all active buffers to the 261 * QUEUED state 262 */ 263 return_all_buffers(skel, VB2_BUF_STATE_QUEUED); 264 } 265 return ret; 266 } 267 268 /* 269 * Stop the DMA engine. Any remaining buffers in the DMA queue are dequeued 270 * and passed on to the vb2 framework marked as STATE_ERROR. 271 */ 272 static void stop_streaming(struct vb2_queue *vq) 273 { 274 struct skeleton *skel = vb2_get_drv_priv(vq); 275 276 /* TODO: stop DMA */ 277 278 /* Release all active buffers */ 279 return_all_buffers(skel, VB2_BUF_STATE_ERROR); 280 } 281 282 /* 283 * The vb2 queue ops. Note that since q->lock is set we can use the standard 284 * vb2_ops_wait_prepare/finish helper functions. If q->lock would be NULL, 285 * then this driver would have to provide these ops. 286 */ 287 static const struct vb2_ops skel_qops = { 288 .queue_setup = queue_setup, 289 .buf_prepare = buffer_prepare, 290 .buf_queue = buffer_queue, 291 .start_streaming = start_streaming, 292 .stop_streaming = stop_streaming, 293 .wait_prepare = vb2_ops_wait_prepare, 294 .wait_finish = vb2_ops_wait_finish, 295 }; 296 297 /* 298 * Required ioctl querycap. Note that the version field is prefilled with 299 * the version of the kernel. 300 */ 301 static int skeleton_querycap(struct file *file, void *priv, 302 struct v4l2_capability *cap) 303 { 304 struct skeleton *skel = video_drvdata(file); 305 306 strlcpy(cap->driver, KBUILD_MODNAME, sizeof(cap->driver)); 307 strlcpy(cap->card, "V4L2 PCI Skeleton", sizeof(cap->card)); 308 snprintf(cap->bus_info, sizeof(cap->bus_info), "PCI:%s", 309 pci_name(skel->pdev)); 310 return 0; 311 } 312 313 /* 314 * Helper function to check and correct struct v4l2_pix_format. It's used 315 * not only in VIDIOC_TRY/S_FMT, but also elsewhere if changes to the SDTV 316 * standard, HDTV timings or the video input would require updating the 317 * current format. 318 */ 319 static void skeleton_fill_pix_format(struct skeleton *skel, 320 struct v4l2_pix_format *pix) 321 { 322 pix->pixelformat = V4L2_PIX_FMT_YUYV; 323 if (skel->input == 0) { 324 /* S-Video input */ 325 pix->width = 720; 326 pix->height = (skel->std & V4L2_STD_525_60) ? 480 : 576; 327 pix->field = V4L2_FIELD_INTERLACED; 328 pix->colorspace = V4L2_COLORSPACE_SMPTE170M; 329 } else { 330 /* HDMI input */ 331 pix->width = skel->timings.bt.width; 332 pix->height = skel->timings.bt.height; 333 if (skel->timings.bt.interlaced) { 334 pix->field = V4L2_FIELD_ALTERNATE; 335 pix->height /= 2; 336 } else { 337 pix->field = V4L2_FIELD_NONE; 338 } 339 pix->colorspace = V4L2_COLORSPACE_REC709; 340 } 341 342 /* 343 * The YUYV format is four bytes for every two pixels, so bytesperline 344 * is width * 2. 345 */ 346 pix->bytesperline = pix->width * 2; 347 pix->sizeimage = pix->bytesperline * pix->height; 348 pix->priv = 0; 349 } 350 351 static int skeleton_try_fmt_vid_cap(struct file *file, void *priv, 352 struct v4l2_format *f) 353 { 354 struct skeleton *skel = video_drvdata(file); 355 struct v4l2_pix_format *pix = &f->fmt.pix; 356 357 /* 358 * Due to historical reasons providing try_fmt with an unsupported 359 * pixelformat will return -EINVAL for video receivers. Webcam drivers, 360 * however, will silently correct the pixelformat. Some video capture 361 * applications rely on this behavior... 362 */ 363 if (pix->pixelformat != V4L2_PIX_FMT_YUYV) 364 return -EINVAL; 365 skeleton_fill_pix_format(skel, pix); 366 return 0; 367 } 368 369 static int skeleton_s_fmt_vid_cap(struct file *file, void *priv, 370 struct v4l2_format *f) 371 { 372 struct skeleton *skel = video_drvdata(file); 373 int ret; 374 375 ret = skeleton_try_fmt_vid_cap(file, priv, f); 376 if (ret) 377 return ret; 378 379 /* 380 * It is not allowed to change the format while buffers for use with 381 * streaming have already been allocated. 382 */ 383 if (vb2_is_busy(&skel->queue)) 384 return -EBUSY; 385 386 /* TODO: change format */ 387 skel->format = f->fmt.pix; 388 return 0; 389 } 390 391 static int skeleton_g_fmt_vid_cap(struct file *file, void *priv, 392 struct v4l2_format *f) 393 { 394 struct skeleton *skel = video_drvdata(file); 395 396 f->fmt.pix = skel->format; 397 return 0; 398 } 399 400 static int skeleton_enum_fmt_vid_cap(struct file *file, void *priv, 401 struct v4l2_fmtdesc *f) 402 { 403 if (f->index != 0) 404 return -EINVAL; 405 406 f->pixelformat = V4L2_PIX_FMT_YUYV; 407 return 0; 408 } 409 410 static int skeleton_s_std(struct file *file, void *priv, v4l2_std_id std) 411 { 412 struct skeleton *skel = video_drvdata(file); 413 414 /* S_STD is not supported on the HDMI input */ 415 if (skel->input) 416 return -ENODATA; 417 418 /* 419 * No change, so just return. Some applications call S_STD again after 420 * the buffers for streaming have been set up, so we have to allow for 421 * this behavior. 422 */ 423 if (std == skel->std) 424 return 0; 425 426 /* 427 * Changing the standard implies a format change, which is not allowed 428 * while buffers for use with streaming have already been allocated. 429 */ 430 if (vb2_is_busy(&skel->queue)) 431 return -EBUSY; 432 433 /* TODO: handle changing std */ 434 435 skel->std = std; 436 437 /* Update the internal format */ 438 skeleton_fill_pix_format(skel, &skel->format); 439 return 0; 440 } 441 442 static int skeleton_g_std(struct file *file, void *priv, v4l2_std_id *std) 443 { 444 struct skeleton *skel = video_drvdata(file); 445 446 /* G_STD is not supported on the HDMI input */ 447 if (skel->input) 448 return -ENODATA; 449 450 *std = skel->std; 451 return 0; 452 } 453 454 /* 455 * Query the current standard as seen by the hardware. This function shall 456 * never actually change the standard, it just detects and reports. 457 * The framework will initially set *std to tvnorms (i.e. the set of 458 * supported standards by this input), and this function should just AND 459 * this value. If there is no signal, then *std should be set to 0. 460 */ 461 static int skeleton_querystd(struct file *file, void *priv, v4l2_std_id *std) 462 { 463 struct skeleton *skel = video_drvdata(file); 464 465 /* QUERY_STD is not supported on the HDMI input */ 466 if (skel->input) 467 return -ENODATA; 468 469 #ifdef TODO 470 /* 471 * Query currently seen standard. Initial value of *std is 472 * V4L2_STD_ALL. This function should look something like this: 473 */ 474 get_signal_info(); 475 if (no_signal) { 476 *std = 0; 477 return 0; 478 } 479 /* Use signal information to reduce the number of possible standards */ 480 if (signal_has_525_lines) 481 *std &= V4L2_STD_525_60; 482 else 483 *std &= V4L2_STD_625_50; 484 #endif 485 return 0; 486 } 487 488 static int skeleton_s_dv_timings(struct file *file, void *_fh, 489 struct v4l2_dv_timings *timings) 490 { 491 struct skeleton *skel = video_drvdata(file); 492 493 /* S_DV_TIMINGS is not supported on the S-Video input */ 494 if (skel->input == 0) 495 return -ENODATA; 496 497 /* Quick sanity check */ 498 if (!v4l2_valid_dv_timings(timings, &skel_timings_cap, NULL, NULL)) 499 return -EINVAL; 500 501 /* Check if the timings are part of the CEA-861 timings. */ 502 if (!v4l2_find_dv_timings_cap(timings, &skel_timings_cap, 503 0, NULL, NULL)) 504 return -EINVAL; 505 506 /* Return 0 if the new timings are the same as the current timings. */ 507 if (v4l2_match_dv_timings(timings, &skel->timings, 0, false)) 508 return 0; 509 510 /* 511 * Changing the timings implies a format change, which is not allowed 512 * while buffers for use with streaming have already been allocated. 513 */ 514 if (vb2_is_busy(&skel->queue)) 515 return -EBUSY; 516 517 /* TODO: Configure new timings */ 518 519 /* Save timings */ 520 skel->timings = *timings; 521 522 /* Update the internal format */ 523 skeleton_fill_pix_format(skel, &skel->format); 524 return 0; 525 } 526 527 static int skeleton_g_dv_timings(struct file *file, void *_fh, 528 struct v4l2_dv_timings *timings) 529 { 530 struct skeleton *skel = video_drvdata(file); 531 532 /* G_DV_TIMINGS is not supported on the S-Video input */ 533 if (skel->input == 0) 534 return -ENODATA; 535 536 *timings = skel->timings; 537 return 0; 538 } 539 540 static int skeleton_enum_dv_timings(struct file *file, void *_fh, 541 struct v4l2_enum_dv_timings *timings) 542 { 543 struct skeleton *skel = video_drvdata(file); 544 545 /* ENUM_DV_TIMINGS is not supported on the S-Video input */ 546 if (skel->input == 0) 547 return -ENODATA; 548 549 return v4l2_enum_dv_timings_cap(timings, &skel_timings_cap, 550 NULL, NULL); 551 } 552 553 /* 554 * Query the current timings as seen by the hardware. This function shall 555 * never actually change the timings, it just detects and reports. 556 * If no signal is detected, then return -ENOLINK. If the hardware cannot 557 * lock to the signal, then return -ENOLCK. If the signal is out of range 558 * of the capabilities of the system (e.g., it is possible that the receiver 559 * can lock but that the DMA engine it is connected to cannot handle 560 * pixelclocks above a certain frequency), then -ERANGE is returned. 561 */ 562 static int skeleton_query_dv_timings(struct file *file, void *_fh, 563 struct v4l2_dv_timings *timings) 564 { 565 struct skeleton *skel = video_drvdata(file); 566 567 /* QUERY_DV_TIMINGS is not supported on the S-Video input */ 568 if (skel->input == 0) 569 return -ENODATA; 570 571 #ifdef TODO 572 /* 573 * Query currently seen timings. This function should look 574 * something like this: 575 */ 576 detect_timings(); 577 if (no_signal) 578 return -ENOLINK; 579 if (cannot_lock_to_signal) 580 return -ENOLCK; 581 if (signal_out_of_range_of_capabilities) 582 return -ERANGE; 583 584 /* Useful for debugging */ 585 v4l2_print_dv_timings(skel->v4l2_dev.name, "query_dv_timings:", 586 timings, true); 587 #endif 588 return 0; 589 } 590 591 static int skeleton_dv_timings_cap(struct file *file, void *fh, 592 struct v4l2_dv_timings_cap *cap) 593 { 594 struct skeleton *skel = video_drvdata(file); 595 596 /* DV_TIMINGS_CAP is not supported on the S-Video input */ 597 if (skel->input == 0) 598 return -ENODATA; 599 *cap = skel_timings_cap; 600 return 0; 601 } 602 603 static int skeleton_enum_input(struct file *file, void *priv, 604 struct v4l2_input *i) 605 { 606 if (i->index > 1) 607 return -EINVAL; 608 609 i->type = V4L2_INPUT_TYPE_CAMERA; 610 if (i->index == 0) { 611 i->std = SKEL_TVNORMS; 612 strlcpy(i->name, "S-Video", sizeof(i->name)); 613 i->capabilities = V4L2_IN_CAP_STD; 614 } else { 615 i->std = 0; 616 strlcpy(i->name, "HDMI", sizeof(i->name)); 617 i->capabilities = V4L2_IN_CAP_DV_TIMINGS; 618 } 619 return 0; 620 } 621 622 static int skeleton_s_input(struct file *file, void *priv, unsigned int i) 623 { 624 struct skeleton *skel = video_drvdata(file); 625 626 if (i > 1) 627 return -EINVAL; 628 629 /* 630 * Changing the input implies a format change, which is not allowed 631 * while buffers for use with streaming have already been allocated. 632 */ 633 if (vb2_is_busy(&skel->queue)) 634 return -EBUSY; 635 636 skel->input = i; 637 /* 638 * Update tvnorms. The tvnorms value is used by the core to implement 639 * VIDIOC_ENUMSTD so it has to be correct. If tvnorms == 0, then 640 * ENUMSTD will return -ENODATA. 641 */ 642 skel->vdev.tvnorms = i ? 0 : SKEL_TVNORMS; 643 644 /* Update the internal format */ 645 skeleton_fill_pix_format(skel, &skel->format); 646 return 0; 647 } 648 649 static int skeleton_g_input(struct file *file, void *priv, unsigned int *i) 650 { 651 struct skeleton *skel = video_drvdata(file); 652 653 *i = skel->input; 654 return 0; 655 } 656 657 /* The control handler. */ 658 static int skeleton_s_ctrl(struct v4l2_ctrl *ctrl) 659 { 660 /*struct skeleton *skel = 661 container_of(ctrl->handler, struct skeleton, ctrl_handler);*/ 662 663 switch (ctrl->id) { 664 case V4L2_CID_BRIGHTNESS: 665 /* TODO: set brightness to ctrl->val */ 666 break; 667 case V4L2_CID_CONTRAST: 668 /* TODO: set contrast to ctrl->val */ 669 break; 670 case V4L2_CID_SATURATION: 671 /* TODO: set saturation to ctrl->val */ 672 break; 673 case V4L2_CID_HUE: 674 /* TODO: set hue to ctrl->val */ 675 break; 676 default: 677 return -EINVAL; 678 } 679 return 0; 680 } 681 682 /* ------------------------------------------------------------------ 683 File operations for the device 684 ------------------------------------------------------------------*/ 685 686 static const struct v4l2_ctrl_ops skel_ctrl_ops = { 687 .s_ctrl = skeleton_s_ctrl, 688 }; 689 690 /* 691 * The set of all supported ioctls. Note that all the streaming ioctls 692 * use the vb2 helper functions that take care of all the locking and 693 * that also do ownership tracking (i.e. only the filehandle that requested 694 * the buffers can call the streaming ioctls, all other filehandles will 695 * receive -EBUSY if they attempt to call the same streaming ioctls). 696 * 697 * The last three ioctls also use standard helper functions: these implement 698 * standard behavior for drivers with controls. 699 */ 700 static const struct v4l2_ioctl_ops skel_ioctl_ops = { 701 .vidioc_querycap = skeleton_querycap, 702 .vidioc_try_fmt_vid_cap = skeleton_try_fmt_vid_cap, 703 .vidioc_s_fmt_vid_cap = skeleton_s_fmt_vid_cap, 704 .vidioc_g_fmt_vid_cap = skeleton_g_fmt_vid_cap, 705 .vidioc_enum_fmt_vid_cap = skeleton_enum_fmt_vid_cap, 706 707 .vidioc_g_std = skeleton_g_std, 708 .vidioc_s_std = skeleton_s_std, 709 .vidioc_querystd = skeleton_querystd, 710 711 .vidioc_s_dv_timings = skeleton_s_dv_timings, 712 .vidioc_g_dv_timings = skeleton_g_dv_timings, 713 .vidioc_enum_dv_timings = skeleton_enum_dv_timings, 714 .vidioc_query_dv_timings = skeleton_query_dv_timings, 715 .vidioc_dv_timings_cap = skeleton_dv_timings_cap, 716 717 .vidioc_enum_input = skeleton_enum_input, 718 .vidioc_g_input = skeleton_g_input, 719 .vidioc_s_input = skeleton_s_input, 720 721 .vidioc_reqbufs = vb2_ioctl_reqbufs, 722 .vidioc_create_bufs = vb2_ioctl_create_bufs, 723 .vidioc_querybuf = vb2_ioctl_querybuf, 724 .vidioc_qbuf = vb2_ioctl_qbuf, 725 .vidioc_dqbuf = vb2_ioctl_dqbuf, 726 .vidioc_expbuf = vb2_ioctl_expbuf, 727 .vidioc_streamon = vb2_ioctl_streamon, 728 .vidioc_streamoff = vb2_ioctl_streamoff, 729 730 .vidioc_log_status = v4l2_ctrl_log_status, 731 .vidioc_subscribe_event = v4l2_ctrl_subscribe_event, 732 .vidioc_unsubscribe_event = v4l2_event_unsubscribe, 733 }; 734 735 /* 736 * The set of file operations. Note that all these ops are standard core 737 * helper functions. 738 */ 739 static const struct v4l2_file_operations skel_fops = { 740 .owner = THIS_MODULE, 741 .open = v4l2_fh_open, 742 .release = vb2_fop_release, 743 .unlocked_ioctl = video_ioctl2, 744 .read = vb2_fop_read, 745 .mmap = vb2_fop_mmap, 746 .poll = vb2_fop_poll, 747 }; 748 749 /* 750 * The initial setup of this device instance. Note that the initial state of 751 * the driver should be complete. So the initial format, standard, timings 752 * and video input should all be initialized to some reasonable value. 753 */ 754 static int skeleton_probe(struct pci_dev *pdev, const struct pci_device_id *ent) 755 { 756 /* The initial timings are chosen to be 720p60. */ 757 static const struct v4l2_dv_timings timings_def = 758 V4L2_DV_BT_CEA_1280X720P60; 759 struct skeleton *skel; 760 struct video_device *vdev; 761 struct v4l2_ctrl_handler *hdl; 762 struct vb2_queue *q; 763 int ret; 764 765 /* Enable PCI */ 766 ret = pci_enable_device(pdev); 767 if (ret) 768 return ret; 769 ret = pci_set_dma_mask(pdev, DMA_BIT_MASK(32)); 770 if (ret) { 771 dev_err(&pdev->dev, "no suitable DMA available.\n"); 772 goto disable_pci; 773 } 774 775 /* Allocate a new instance */ 776 skel = devm_kzalloc(&pdev->dev, sizeof(struct skeleton), GFP_KERNEL); 777 if (!skel) { 778 ret = -ENOMEM; 779 goto disable_pci; 780 } 781 782 /* Allocate the interrupt */ 783 ret = devm_request_irq(&pdev->dev, pdev->irq, 784 skeleton_irq, 0, KBUILD_MODNAME, skel); 785 if (ret) { 786 dev_err(&pdev->dev, "request_irq failed\n"); 787 goto disable_pci; 788 } 789 skel->pdev = pdev; 790 791 /* Fill in the initial format-related settings */ 792 skel->timings = timings_def; 793 skel->std = V4L2_STD_625_50; 794 skeleton_fill_pix_format(skel, &skel->format); 795 796 /* Initialize the top-level structure */ 797 ret = v4l2_device_register(&pdev->dev, &skel->v4l2_dev); 798 if (ret) 799 goto disable_pci; 800 801 mutex_init(&skel->lock); 802 803 /* Add the controls */ 804 hdl = &skel->ctrl_handler; 805 v4l2_ctrl_handler_init(hdl, 4); 806 v4l2_ctrl_new_std(hdl, &skel_ctrl_ops, 807 V4L2_CID_BRIGHTNESS, 0, 255, 1, 127); 808 v4l2_ctrl_new_std(hdl, &skel_ctrl_ops, 809 V4L2_CID_CONTRAST, 0, 255, 1, 16); 810 v4l2_ctrl_new_std(hdl, &skel_ctrl_ops, 811 V4L2_CID_SATURATION, 0, 255, 1, 127); 812 v4l2_ctrl_new_std(hdl, &skel_ctrl_ops, 813 V4L2_CID_HUE, -128, 127, 1, 0); 814 if (hdl->error) { 815 ret = hdl->error; 816 goto free_hdl; 817 } 818 skel->v4l2_dev.ctrl_handler = hdl; 819 820 /* Initialize the vb2 queue */ 821 q = &skel->queue; 822 q->type = V4L2_BUF_TYPE_VIDEO_CAPTURE; 823 q->io_modes = VB2_MMAP | VB2_DMABUF | VB2_READ; 824 q->dev = &pdev->dev; 825 q->drv_priv = skel; 826 q->buf_struct_size = sizeof(struct skel_buffer); 827 q->ops = &skel_qops; 828 q->mem_ops = &vb2_dma_contig_memops; 829 q->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC; 830 /* 831 * Assume that this DMA engine needs to have at least two buffers 832 * available before it can be started. The start_streaming() op 833 * won't be called until at least this many buffers are queued up. 834 */ 835 q->min_buffers_needed = 2; 836 /* 837 * The serialization lock for the streaming ioctls. This is the same 838 * as the main serialization lock, but if some of the non-streaming 839 * ioctls could take a long time to execute, then you might want to 840 * have a different lock here to prevent VIDIOC_DQBUF from being 841 * blocked while waiting for another action to finish. This is 842 * generally not needed for PCI devices, but USB devices usually do 843 * want a separate lock here. 844 */ 845 q->lock = &skel->lock; 846 /* 847 * Since this driver can only do 32-bit DMA we must make sure that 848 * the vb2 core will allocate the buffers in 32-bit DMA memory. 849 */ 850 q->gfp_flags = GFP_DMA32; 851 ret = vb2_queue_init(q); 852 if (ret) 853 goto free_hdl; 854 855 INIT_LIST_HEAD(&skel->buf_list); 856 spin_lock_init(&skel->qlock); 857 858 /* Initialize the video_device structure */ 859 vdev = &skel->vdev; 860 strlcpy(vdev->name, KBUILD_MODNAME, sizeof(vdev->name)); 861 /* 862 * There is nothing to clean up, so release is set to an empty release 863 * function. The release callback must be non-NULL. 864 */ 865 vdev->release = video_device_release_empty; 866 vdev->fops = &skel_fops, 867 vdev->ioctl_ops = &skel_ioctl_ops, 868 vdev->device_caps = V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_READWRITE | 869 V4L2_CAP_STREAMING; 870 /* 871 * The main serialization lock. All ioctls are serialized by this 872 * lock. Exception: if q->lock is set, then the streaming ioctls 873 * are serialized by that separate lock. 874 */ 875 vdev->lock = &skel->lock; 876 vdev->queue = q; 877 vdev->v4l2_dev = &skel->v4l2_dev; 878 /* Supported SDTV standards, if any */ 879 vdev->tvnorms = SKEL_TVNORMS; 880 video_set_drvdata(vdev, skel); 881 882 ret = video_register_device(vdev, VFL_TYPE_VIDEO, -1); 883 if (ret) 884 goto free_hdl; 885 886 dev_info(&pdev->dev, "V4L2 PCI Skeleton Driver loaded\n"); 887 return 0; 888 889 free_hdl: 890 v4l2_ctrl_handler_free(&skel->ctrl_handler); 891 v4l2_device_unregister(&skel->v4l2_dev); 892 disable_pci: 893 pci_disable_device(pdev); 894 return ret; 895 } 896 897 static void skeleton_remove(struct pci_dev *pdev) 898 { 899 struct v4l2_device *v4l2_dev = pci_get_drvdata(pdev); 900 struct skeleton *skel = container_of(v4l2_dev, struct skeleton, v4l2_dev); 901 902 video_unregister_device(&skel->vdev); 903 v4l2_ctrl_handler_free(&skel->ctrl_handler); 904 v4l2_device_unregister(&skel->v4l2_dev); 905 pci_disable_device(skel->pdev); 906 } 907 908 static struct pci_driver skeleton_driver = { 909 .name = KBUILD_MODNAME, 910 .probe = skeleton_probe, 911 .remove = skeleton_remove, 912 .id_table = skeleton_pci_tbl, 913 }; 914 915 module_pci_driver(skeleton_driver); 916