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