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-dma-contig.h> 41 42MODULE_DESCRIPTION("V4L2 PCI Skeleton Driver"); 43MODULE_AUTHOR("Hans Verkuil"); 44MODULE_LICENSE("GPL v2"); 45 46/** 47 * struct skeleton - All internal data for one instance of device 48 * @pdev: PCI device 49 * @v4l2_dev: top-level v4l2 device struct 50 * @vdev: video node structure 51 * @ctrl_handler: control handler structure 52 * @lock: ioctl serialization mutex 53 * @std: current SDTV standard 54 * @timings: current HDTV timings 55 * @format: current pix format 56 * @input: current video input (0 = SDTV, 1 = HDTV) 57 * @queue: vb2 video capture queue 58 * @alloc_ctx: vb2 contiguous DMA context 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 */ 63struct 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 struct vb2_alloc_ctx *alloc_ctx; 76 77 spinlock_t qlock; 78 struct list_head buf_list; 79 unsigned field; 80 unsigned sequence; 81}; 82 83struct skel_buffer { 84 struct vb2_buffer vb; 85 struct list_head list; 86}; 87 88static inline struct skel_buffer *to_skel_buffer(struct vb2_buffer *vb2) 89{ 90 return container_of(vb2, struct skel_buffer, vb); 91} 92 93static const struct pci_device_id skeleton_pci_tbl[] = { 94 /* { PCI_DEVICE(PCI_VENDOR_ID_, PCI_DEVICE_ID_) }, */ 95 { 0, } 96}; 97MODULE_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 */ 104static 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 */ 130static 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 v4l2_get_timestamp(&new_buf->vb.v4l2_buf.timestamp); 144 new_buf->vb.v4l2_buf.sequence = skel->sequence++; 145 new_buf->vb.v4l2_buf.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_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 */ 165static int queue_setup(struct vb2_queue *vq, const struct v4l2_format *fmt, 166 unsigned int *nbuffers, unsigned int *nplanes, 167 unsigned int sizes[], void *alloc_ctxs[]) 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 (fmt && fmt->fmt.pix.sizeimage < skel->format.sizeimage) 186 return -EINVAL; 187 *nplanes = 1; 188 sizes[0] = fmt ? fmt->fmt.pix.sizeimage : skel->format.sizeimage; 189 alloc_ctxs[0] = skel->alloc_ctx; 190 return 0; 191} 192 193/* 194 * Prepare the buffer for queueing to the DMA engine: check and set the 195 * payload size. 196 */ 197static int buffer_prepare(struct vb2_buffer *vb) 198{ 199 struct skeleton *skel = vb2_get_drv_priv(vb->vb2_queue); 200 unsigned long size = skel->format.sizeimage; 201 202 if (vb2_plane_size(vb, 0) < size) { 203 dev_err(&skel->pdev->dev, "buffer too small (%lu < %lu)\n", 204 vb2_plane_size(vb, 0), size); 205 return -EINVAL; 206 } 207 208 vb2_set_plane_payload(vb, 0, size); 209 return 0; 210} 211 212/* 213 * Queue this buffer to the DMA engine. 214 */ 215static void buffer_queue(struct vb2_buffer *vb) 216{ 217 struct skeleton *skel = vb2_get_drv_priv(vb->vb2_queue); 218 struct skel_buffer *buf = to_skel_buffer(vb); 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 229static 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, 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 */ 249static 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 */ 272static 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 */ 287static 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 */ 301static 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 cap->device_caps = V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_READWRITE | 311 V4L2_CAP_STREAMING; 312 cap->capabilities = cap->device_caps | V4L2_CAP_DEVICE_CAPS; 313 return 0; 314} 315 316/* 317 * Helper function to check and correct struct v4l2_pix_format. It's used 318 * not only in VIDIOC_TRY/S_FMT, but also elsewhere if changes to the SDTV 319 * standard, HDTV timings or the video input would require updating the 320 * current format. 321 */ 322static void skeleton_fill_pix_format(struct skeleton *skel, 323 struct v4l2_pix_format *pix) 324{ 325 pix->pixelformat = V4L2_PIX_FMT_YUYV; 326 if (skel->input == 0) { 327 /* S-Video input */ 328 pix->width = 720; 329 pix->height = (skel->std & V4L2_STD_525_60) ? 480 : 576; 330 pix->field = V4L2_FIELD_INTERLACED; 331 pix->colorspace = V4L2_COLORSPACE_SMPTE170M; 332 } else { 333 /* HDMI input */ 334 pix->width = skel->timings.bt.width; 335 pix->height = skel->timings.bt.height; 336 if (skel->timings.bt.interlaced) { 337 pix->field = V4L2_FIELD_ALTERNATE; 338 pix->height /= 2; 339 } else { 340 pix->field = V4L2_FIELD_NONE; 341 } 342 pix->colorspace = V4L2_COLORSPACE_REC709; 343 } 344 345 /* 346 * The YUYV format is four bytes for every two pixels, so bytesperline 347 * is width * 2. 348 */ 349 pix->bytesperline = pix->width * 2; 350 pix->sizeimage = pix->bytesperline * pix->height; 351 pix->priv = 0; 352} 353 354static int skeleton_try_fmt_vid_cap(struct file *file, void *priv, 355 struct v4l2_format *f) 356{ 357 struct skeleton *skel = video_drvdata(file); 358 struct v4l2_pix_format *pix = &f->fmt.pix; 359 360 /* 361 * Due to historical reasons providing try_fmt with an unsupported 362 * pixelformat will return -EINVAL for video receivers. Webcam drivers, 363 * however, will silently correct the pixelformat. Some video capture 364 * applications rely on this behavior... 365 */ 366 if (pix->pixelformat != V4L2_PIX_FMT_YUYV) 367 return -EINVAL; 368 skeleton_fill_pix_format(skel, pix); 369 return 0; 370} 371 372static int skeleton_s_fmt_vid_cap(struct file *file, void *priv, 373 struct v4l2_format *f) 374{ 375 struct skeleton *skel = video_drvdata(file); 376 int ret; 377 378 ret = skeleton_try_fmt_vid_cap(file, priv, f); 379 if (ret) 380 return ret; 381 382 /* 383 * It is not allowed to change the format while buffers for use with 384 * streaming have already been allocated. 385 */ 386 if (vb2_is_busy(&skel->queue)) 387 return -EBUSY; 388 389 /* TODO: change format */ 390 skel->format = f->fmt.pix; 391 return 0; 392} 393 394static int skeleton_g_fmt_vid_cap(struct file *file, void *priv, 395 struct v4l2_format *f) 396{ 397 struct skeleton *skel = video_drvdata(file); 398 399 f->fmt.pix = skel->format; 400 return 0; 401} 402 403static int skeleton_enum_fmt_vid_cap(struct file *file, void *priv, 404 struct v4l2_fmtdesc *f) 405{ 406 if (f->index != 0) 407 return -EINVAL; 408 409 strlcpy(f->description, "4:2:2, packed, YUYV", sizeof(f->description)); 410 f->pixelformat = V4L2_PIX_FMT_YUYV; 411 f->flags = 0; 412 return 0; 413} 414 415static int skeleton_s_std(struct file *file, void *priv, v4l2_std_id std) 416{ 417 struct skeleton *skel = video_drvdata(file); 418 419 /* S_STD is not supported on the HDMI input */ 420 if (skel->input) 421 return -ENODATA; 422 423 /* 424 * No change, so just return. Some applications call S_STD again after 425 * the buffers for streaming have been set up, so we have to allow for 426 * this behavior. 427 */ 428 if (std == skel->std) 429 return 0; 430 431 /* 432 * Changing the standard implies a format change, which is not allowed 433 * while buffers for use with streaming have already been allocated. 434 */ 435 if (vb2_is_busy(&skel->queue)) 436 return -EBUSY; 437 438 /* TODO: handle changing std */ 439 440 skel->std = std; 441 442 /* Update the internal format */ 443 skeleton_fill_pix_format(skel, &skel->format); 444 return 0; 445} 446 447static int skeleton_g_std(struct file *file, void *priv, v4l2_std_id *std) 448{ 449 struct skeleton *skel = video_drvdata(file); 450 451 /* G_STD is not supported on the HDMI input */ 452 if (skel->input) 453 return -ENODATA; 454 455 *std = skel->std; 456 return 0; 457} 458 459/* 460 * Query the current standard as seen by the hardware. This function shall 461 * never actually change the standard, it just detects and reports. 462 * The framework will initially set *std to tvnorms (i.e. the set of 463 * supported standards by this input), and this function should just AND 464 * this value. If there is no signal, then *std should be set to 0. 465 */ 466static int skeleton_querystd(struct file *file, void *priv, v4l2_std_id *std) 467{ 468 struct skeleton *skel = video_drvdata(file); 469 470 /* QUERY_STD is not supported on the HDMI input */ 471 if (skel->input) 472 return -ENODATA; 473 474#ifdef TODO 475 /* 476 * Query currently seen standard. Initial value of *std is 477 * V4L2_STD_ALL. This function should look something like this: 478 */ 479 get_signal_info(); 480 if (no_signal) { 481 *std = 0; 482 return 0; 483 } 484 /* Use signal information to reduce the number of possible standards */ 485 if (signal_has_525_lines) 486 *std &= V4L2_STD_525_60; 487 else 488 *std &= V4L2_STD_625_50; 489#endif 490 return 0; 491} 492 493static int skeleton_s_dv_timings(struct file *file, void *_fh, 494 struct v4l2_dv_timings *timings) 495{ 496 struct skeleton *skel = video_drvdata(file); 497 498 /* S_DV_TIMINGS is not supported on the S-Video input */ 499 if (skel->input == 0) 500 return -ENODATA; 501 502 /* Quick sanity check */ 503 if (!v4l2_valid_dv_timings(timings, &skel_timings_cap, NULL, NULL)) 504 return -EINVAL; 505 506 /* Check if the timings are part of the CEA-861 timings. */ 507 if (!v4l2_find_dv_timings_cap(timings, &skel_timings_cap, 508 0, NULL, NULL)) 509 return -EINVAL; 510 511 /* Return 0 if the new timings are the same as the current timings. */ 512 if (v4l2_match_dv_timings(timings, &skel->timings, 0)) 513 return 0; 514 515 /* 516 * Changing the timings implies a format change, which is not allowed 517 * while buffers for use with streaming have already been allocated. 518 */ 519 if (vb2_is_busy(&skel->queue)) 520 return -EBUSY; 521 522 /* TODO: Configure new timings */ 523 524 /* Save timings */ 525 skel->timings = *timings; 526 527 /* Update the internal format */ 528 skeleton_fill_pix_format(skel, &skel->format); 529 return 0; 530} 531 532static int skeleton_g_dv_timings(struct file *file, void *_fh, 533 struct v4l2_dv_timings *timings) 534{ 535 struct skeleton *skel = video_drvdata(file); 536 537 /* G_DV_TIMINGS is not supported on the S-Video input */ 538 if (skel->input == 0) 539 return -ENODATA; 540 541 *timings = skel->timings; 542 return 0; 543} 544 545static int skeleton_enum_dv_timings(struct file *file, void *_fh, 546 struct v4l2_enum_dv_timings *timings) 547{ 548 struct skeleton *skel = video_drvdata(file); 549 550 /* ENUM_DV_TIMINGS is not supported on the S-Video input */ 551 if (skel->input == 0) 552 return -ENODATA; 553 554 return v4l2_enum_dv_timings_cap(timings, &skel_timings_cap, 555 NULL, NULL); 556} 557 558/* 559 * Query the current timings as seen by the hardware. This function shall 560 * never actually change the timings, it just detects and reports. 561 * If no signal is detected, then return -ENOLINK. If the hardware cannot 562 * lock to the signal, then return -ENOLCK. If the signal is out of range 563 * of the capabilities of the system (e.g., it is possible that the receiver 564 * can lock but that the DMA engine it is connected to cannot handle 565 * pixelclocks above a certain frequency), then -ERANGE is returned. 566 */ 567static int skeleton_query_dv_timings(struct file *file, void *_fh, 568 struct v4l2_dv_timings *timings) 569{ 570 struct skeleton *skel = video_drvdata(file); 571 572 /* QUERY_DV_TIMINGS is not supported on the S-Video input */ 573 if (skel->input == 0) 574 return -ENODATA; 575 576#ifdef TODO 577 /* 578 * Query currently seen timings. This function should look 579 * something like this: 580 */ 581 detect_timings(); 582 if (no_signal) 583 return -ENOLINK; 584 if (cannot_lock_to_signal) 585 return -ENOLCK; 586 if (signal_out_of_range_of_capabilities) 587 return -ERANGE; 588 589 /* Useful for debugging */ 590 v4l2_print_dv_timings(skel->v4l2_dev.name, "query_dv_timings:", 591 timings, true); 592#endif 593 return 0; 594} 595 596static int skeleton_dv_timings_cap(struct file *file, void *fh, 597 struct v4l2_dv_timings_cap *cap) 598{ 599 struct skeleton *skel = video_drvdata(file); 600 601 /* DV_TIMINGS_CAP is not supported on the S-Video input */ 602 if (skel->input == 0) 603 return -ENODATA; 604 *cap = skel_timings_cap; 605 return 0; 606} 607 608static int skeleton_enum_input(struct file *file, void *priv, 609 struct v4l2_input *i) 610{ 611 if (i->index > 1) 612 return -EINVAL; 613 614 i->type = V4L2_INPUT_TYPE_CAMERA; 615 if (i->index == 0) { 616 i->std = SKEL_TVNORMS; 617 strlcpy(i->name, "S-Video", sizeof(i->name)); 618 i->capabilities = V4L2_IN_CAP_STD; 619 } else { 620 i->std = 0; 621 strlcpy(i->name, "HDMI", sizeof(i->name)); 622 i->capabilities = V4L2_IN_CAP_DV_TIMINGS; 623 } 624 return 0; 625} 626 627static int skeleton_s_input(struct file *file, void *priv, unsigned int i) 628{ 629 struct skeleton *skel = video_drvdata(file); 630 631 if (i > 1) 632 return -EINVAL; 633 634 /* 635 * Changing the input implies a format change, which is not allowed 636 * while buffers for use with streaming have already been allocated. 637 */ 638 if (vb2_is_busy(&skel->queue)) 639 return -EBUSY; 640 641 skel->input = i; 642 /* 643 * Update tvnorms. The tvnorms value is used by the core to implement 644 * VIDIOC_ENUMSTD so it has to be correct. If tvnorms == 0, then 645 * ENUMSTD will return -ENODATA. 646 */ 647 skel->vdev.tvnorms = i ? 0 : SKEL_TVNORMS; 648 649 /* Update the internal format */ 650 skeleton_fill_pix_format(skel, &skel->format); 651 return 0; 652} 653 654static int skeleton_g_input(struct file *file, void *priv, unsigned int *i) 655{ 656 struct skeleton *skel = video_drvdata(file); 657 658 *i = skel->input; 659 return 0; 660} 661 662/* The control handler. */ 663static int skeleton_s_ctrl(struct v4l2_ctrl *ctrl) 664{ 665 /*struct skeleton *skel = 666 container_of(ctrl->handler, struct skeleton, ctrl_handler);*/ 667 668 switch (ctrl->id) { 669 case V4L2_CID_BRIGHTNESS: 670 /* TODO: set brightness to ctrl->val */ 671 break; 672 case V4L2_CID_CONTRAST: 673 /* TODO: set contrast to ctrl->val */ 674 break; 675 case V4L2_CID_SATURATION: 676 /* TODO: set saturation to ctrl->val */ 677 break; 678 case V4L2_CID_HUE: 679 /* TODO: set hue to ctrl->val */ 680 break; 681 default: 682 return -EINVAL; 683 } 684 return 0; 685} 686 687/* ------------------------------------------------------------------ 688 File operations for the device 689 ------------------------------------------------------------------*/ 690 691static const struct v4l2_ctrl_ops skel_ctrl_ops = { 692 .s_ctrl = skeleton_s_ctrl, 693}; 694 695/* 696 * The set of all supported ioctls. Note that all the streaming ioctls 697 * use the vb2 helper functions that take care of all the locking and 698 * that also do ownership tracking (i.e. only the filehandle that requested 699 * the buffers can call the streaming ioctls, all other filehandles will 700 * receive -EBUSY if they attempt to call the same streaming ioctls). 701 * 702 * The last three ioctls also use standard helper functions: these implement 703 * standard behavior for drivers with controls. 704 */ 705static const struct v4l2_ioctl_ops skel_ioctl_ops = { 706 .vidioc_querycap = skeleton_querycap, 707 .vidioc_try_fmt_vid_cap = skeleton_try_fmt_vid_cap, 708 .vidioc_s_fmt_vid_cap = skeleton_s_fmt_vid_cap, 709 .vidioc_g_fmt_vid_cap = skeleton_g_fmt_vid_cap, 710 .vidioc_enum_fmt_vid_cap = skeleton_enum_fmt_vid_cap, 711 712 .vidioc_g_std = skeleton_g_std, 713 .vidioc_s_std = skeleton_s_std, 714 .vidioc_querystd = skeleton_querystd, 715 716 .vidioc_s_dv_timings = skeleton_s_dv_timings, 717 .vidioc_g_dv_timings = skeleton_g_dv_timings, 718 .vidioc_enum_dv_timings = skeleton_enum_dv_timings, 719 .vidioc_query_dv_timings = skeleton_query_dv_timings, 720 .vidioc_dv_timings_cap = skeleton_dv_timings_cap, 721 722 .vidioc_enum_input = skeleton_enum_input, 723 .vidioc_g_input = skeleton_g_input, 724 .vidioc_s_input = skeleton_s_input, 725 726 .vidioc_reqbufs = vb2_ioctl_reqbufs, 727 .vidioc_create_bufs = vb2_ioctl_create_bufs, 728 .vidioc_querybuf = vb2_ioctl_querybuf, 729 .vidioc_qbuf = vb2_ioctl_qbuf, 730 .vidioc_dqbuf = vb2_ioctl_dqbuf, 731 .vidioc_expbuf = vb2_ioctl_expbuf, 732 .vidioc_streamon = vb2_ioctl_streamon, 733 .vidioc_streamoff = vb2_ioctl_streamoff, 734 735 .vidioc_log_status = v4l2_ctrl_log_status, 736 .vidioc_subscribe_event = v4l2_ctrl_subscribe_event, 737 .vidioc_unsubscribe_event = v4l2_event_unsubscribe, 738}; 739 740/* 741 * The set of file operations. Note that all these ops are standard core 742 * helper functions. 743 */ 744static const struct v4l2_file_operations skel_fops = { 745 .owner = THIS_MODULE, 746 .open = v4l2_fh_open, 747 .release = vb2_fop_release, 748 .unlocked_ioctl = video_ioctl2, 749 .read = vb2_fop_read, 750 .mmap = vb2_fop_mmap, 751 .poll = vb2_fop_poll, 752}; 753 754/* 755 * The initial setup of this device instance. Note that the initial state of 756 * the driver should be complete. So the initial format, standard, timings 757 * and video input should all be initialized to some reasonable value. 758 */ 759static int skeleton_probe(struct pci_dev *pdev, const struct pci_device_id *ent) 760{ 761 /* The initial timings are chosen to be 720p60. */ 762 static const struct v4l2_dv_timings timings_def = 763 V4L2_DV_BT_CEA_1280X720P60; 764 struct skeleton *skel; 765 struct video_device *vdev; 766 struct v4l2_ctrl_handler *hdl; 767 struct vb2_queue *q; 768 int ret; 769 770 /* Enable PCI */ 771 ret = pci_enable_device(pdev); 772 if (ret) 773 return ret; 774 ret = pci_set_dma_mask(pdev, DMA_BIT_MASK(32)); 775 if (ret) { 776 dev_err(&pdev->dev, "no suitable DMA available.\n"); 777 goto disable_pci; 778 } 779 780 /* Allocate a new instance */ 781 skel = devm_kzalloc(&pdev->dev, sizeof(struct skeleton), GFP_KERNEL); 782 if (!skel) 783 return -ENOMEM; 784 785 /* Allocate the interrupt */ 786 ret = devm_request_irq(&pdev->dev, pdev->irq, 787 skeleton_irq, 0, KBUILD_MODNAME, skel); 788 if (ret) { 789 dev_err(&pdev->dev, "request_irq failed\n"); 790 goto disable_pci; 791 } 792 skel->pdev = pdev; 793 794 /* Fill in the initial format-related settings */ 795 skel->timings = timings_def; 796 skel->std = V4L2_STD_625_50; 797 skeleton_fill_pix_format(skel, &skel->format); 798 799 /* Initialize the top-level structure */ 800 ret = v4l2_device_register(&pdev->dev, &skel->v4l2_dev); 801 if (ret) 802 goto disable_pci; 803 804 mutex_init(&skel->lock); 805 806 /* Add the controls */ 807 hdl = &skel->ctrl_handler; 808 v4l2_ctrl_handler_init(hdl, 4); 809 v4l2_ctrl_new_std(hdl, &skel_ctrl_ops, 810 V4L2_CID_BRIGHTNESS, 0, 255, 1, 127); 811 v4l2_ctrl_new_std(hdl, &skel_ctrl_ops, 812 V4L2_CID_CONTRAST, 0, 255, 1, 16); 813 v4l2_ctrl_new_std(hdl, &skel_ctrl_ops, 814 V4L2_CID_SATURATION, 0, 255, 1, 127); 815 v4l2_ctrl_new_std(hdl, &skel_ctrl_ops, 816 V4L2_CID_HUE, -128, 127, 1, 0); 817 if (hdl->error) { 818 ret = hdl->error; 819 goto free_hdl; 820 } 821 skel->v4l2_dev.ctrl_handler = hdl; 822 823 /* Initialize the vb2 queue */ 824 q = &skel->queue; 825 q->type = V4L2_BUF_TYPE_VIDEO_CAPTURE; 826 q->io_modes = VB2_MMAP | VB2_DMABUF | VB2_READ; 827 q->drv_priv = skel; 828 q->buf_struct_size = sizeof(struct skel_buffer); 829 q->ops = &skel_qops; 830 q->mem_ops = &vb2_dma_contig_memops; 831 q->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC; 832 /* 833 * Assume that this DMA engine needs to have at least two buffers 834 * available before it can be started. The start_streaming() op 835 * won't be called until at least this many buffers are queued up. 836 */ 837 q->min_buffers_needed = 2; 838 /* 839 * The serialization lock for the streaming ioctls. This is the same 840 * as the main serialization lock, but if some of the non-streaming 841 * ioctls could take a long time to execute, then you might want to 842 * have a different lock here to prevent VIDIOC_DQBUF from being 843 * blocked while waiting for another action to finish. This is 844 * generally not needed for PCI devices, but USB devices usually do 845 * want a separate lock here. 846 */ 847 q->lock = &skel->lock; 848 /* 849 * Since this driver can only do 32-bit DMA we must make sure that 850 * the vb2 core will allocate the buffers in 32-bit DMA memory. 851 */ 852 q->gfp_flags = GFP_DMA32; 853 ret = vb2_queue_init(q); 854 if (ret) 855 goto free_hdl; 856 857 skel->alloc_ctx = vb2_dma_contig_init_ctx(&pdev->dev); 858 if (IS_ERR(skel->alloc_ctx)) { 859 dev_err(&pdev->dev, "Can't allocate buffer context"); 860 ret = PTR_ERR(skel->alloc_ctx); 861 goto free_hdl; 862 } 863 INIT_LIST_HEAD(&skel->buf_list); 864 spin_lock_init(&skel->qlock); 865 866 /* Initialize the video_device structure */ 867 vdev = &skel->vdev; 868 strlcpy(vdev->name, KBUILD_MODNAME, sizeof(vdev->name)); 869 /* 870 * There is nothing to clean up, so release is set to an empty release 871 * function. The release callback must be non-NULL. 872 */ 873 vdev->release = video_device_release_empty; 874 vdev->fops = &skel_fops, 875 vdev->ioctl_ops = &skel_ioctl_ops, 876 /* 877 * The main serialization lock. All ioctls are serialized by this 878 * lock. Exception: if q->lock is set, then the streaming ioctls 879 * are serialized by that separate lock. 880 */ 881 vdev->lock = &skel->lock; 882 vdev->queue = q; 883 vdev->v4l2_dev = &skel->v4l2_dev; 884 /* Supported SDTV standards, if any */ 885 vdev->tvnorms = SKEL_TVNORMS; 886 video_set_drvdata(vdev, skel); 887 888 ret = video_register_device(vdev, VFL_TYPE_GRABBER, -1); 889 if (ret) 890 goto free_ctx; 891 892 dev_info(&pdev->dev, "V4L2 PCI Skeleton Driver loaded\n"); 893 return 0; 894 895free_ctx: 896 vb2_dma_contig_cleanup_ctx(skel->alloc_ctx); 897free_hdl: 898 v4l2_ctrl_handler_free(&skel->ctrl_handler); 899 v4l2_device_unregister(&skel->v4l2_dev); 900disable_pci: 901 pci_disable_device(pdev); 902 return ret; 903} 904 905static void skeleton_remove(struct pci_dev *pdev) 906{ 907 struct v4l2_device *v4l2_dev = pci_get_drvdata(pdev); 908 struct skeleton *skel = container_of(v4l2_dev, struct skeleton, v4l2_dev); 909 910 video_unregister_device(&skel->vdev); 911 v4l2_ctrl_handler_free(&skel->ctrl_handler); 912 vb2_dma_contig_cleanup_ctx(skel->alloc_ctx); 913 v4l2_device_unregister(&skel->v4l2_dev); 914 pci_disable_device(skel->pdev); 915} 916 917static struct pci_driver skeleton_driver = { 918 .name = KBUILD_MODNAME, 919 .probe = skeleton_probe, 920 .remove = skeleton_remove, 921 .id_table = skeleton_pci_tbl, 922}; 923 924module_pci_driver(skeleton_driver); 925