samples/v4l/v4l2-pci-skeleton.c

   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  * @alloc_ctx: vb2 contiguous DMA context
  60  * @qlock: spinlock controlling access to buf_list and sequence
  61  * @buf_list: list of buffers queued for DMA
  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         struct vb2_alloc_ctx *alloc_ctx;
  77
  78         spinlock_t qlock;
  79         struct list_head buf_list;
  80         unsigned field;
  81         unsigned sequence;
  82 };
  83
  84 struct skel_buffer {
  85         struct vb2_buffer vb;
  86         struct list_head list;
  87 };
  88
  89 static inline struct skel_buffer *to_skel_buffer(struct vb2_buffer *vb2)
  90 {
  91         return container_of(vb2, struct skel_buffer, vb);
  92 }
  93
  94 static const struct pci_device_id skeleton_pci_tbl[] = {
  95         /* { PCI_DEVICE(PCI_VENDOR_ID_, PCI_DEVICE_ID_) }, */
  96         { 0, }
  97 };
  98 MODULE_DEVICE_TABLE(pci, skeleton_pci_tbl);
  99
 100 /*
 101  * HDTV: this structure has the capabilities of the HDTV receiver.
 102  * It is used to constrain the huge list of possible formats based
 103  * upon the hardware capabilities.
 104  */
 105 static const struct v4l2_dv_timings_cap skel_timings_cap = {
 106         .type = V4L2_DV_BT_656_1120,
 107         /* keep this initialization for compatibility with GCC < 4.4.6 */
 108         .reserved = { 0 },
 109         V4L2_INIT_BT_TIMINGS(
 110                 720, 1920,              /* min/max width */
 111                 480, 1080,              /* min/max height */
 112                 27000000, 74250000,     /* min/max pixelclock*/
 113                 V4L2_DV_BT_STD_CEA861,  /* Supported standards */
 114                 /* capabilities */
 115                 V4L2_DV_BT_CAP_INTERLACED | V4L2_DV_BT_CAP_PROGRESSIVE
 116         )
 117 };
 118
 119 /*
 120  * Supported SDTV standards. This does the same job as skel_timings_cap, but
 121  * for standard TV formats.
 122  */
 123 #define SKEL_TVNORMS V4L2_STD_ALL
 124
 125 /*
 126  * Interrupt handler: typically interrupts happen after a new frame has been
 127  * captured. It is the job of the handler to remove the new frame from the
 128  * internal list and give it back to the vb2 framework, updating the sequence
 129  * counter, field and timestamp at the same time.
 130  */
 131 static irqreturn_t skeleton_irq(int irq, void *dev_id)
 132 {
 133 #ifdef TODO
 134         struct skeleton *skel = dev_id;
 135
 136         /* handle interrupt */
 137
 138         /* Once a new frame has been captured, mark it as done like this: */
 139         if (captured_new_frame) {
 140                 ...
 141                 spin_lock(&skel->qlock);
 142                 list_del(&new_buf->list);
 143                 spin_unlock(&skel->qlock);
 144                 v4l2_get_timestamp(&new_buf->vb.v4l2_buf.timestamp);
 145                 new_buf->vb.v4l2_buf.sequence = skel->sequence++;
 146                 new_buf->vb.v4l2_buf.field = skel->field;
 147                 if (skel->format.field == V4L2_FIELD_ALTERNATE) {
 148                         if (skel->field == V4L2_FIELD_BOTTOM)
 149                                 skel->field = V4L2_FIELD_TOP;
 150                         else if (skel->field == V4L2_FIELD_TOP)
 151                                 skel->field = V4L2_FIELD_BOTTOM;
 152                 }
 153                 vb2_buffer_done(&new_buf->vb, VB2_BUF_STATE_DONE);
 154         }
 155 #endif
 156         return IRQ_HANDLED;
 157 }
 158
 159 /*
 160  * Setup the constraints of the queue: besides setting the number of planes
 161  * per buffer and the size and allocation context of each plane, it also
 162  * checks if sufficient buffers have been allocated. Usually 3 is a good
 163  * minimum number: many DMA engines need a minimum of 2 buffers in the
 164  * queue and you need to have another available for userspace processing.
 165  */
 166 static int queue_setup(struct vb2_queue *vq,
 167                        unsigned int *nbuffers, unsigned int *nplanes,
 168                        unsigned int sizes[], void *alloc_ctxs[])
 169 {
 170         struct skeleton *skel = vb2_get_drv_priv(vq);
 171
 172         skel->field = skel->format.field;
 173         if (skel->field == V4L2_FIELD_ALTERNATE) {
 174                 /*
 175                  * You cannot use read() with FIELD_ALTERNATE since the field
 176                  * information (TOP/BOTTOM) cannot be passed back to the user.
 177                  */
 178                 if (vb2_fileio_is_active(vq))
 179                         return -EINVAL;
 180                 skel->field = V4L2_FIELD_TOP;
 181         }
 182
 183         if (vq->num_buffers + *nbuffers < 3)
 184                 *nbuffers = 3 - vq->num_buffers;
 185         alloc_ctxs[0] = skel->alloc_ctx;
 186
 187         if (*nplanes)
 188                 return sizes[0] < skel->format.sizeimage ? -EINVAL : 0;
 189         *nplanes = 1;
 190         sizes[0] = skel->format.sizeimage;
 191         return 0;
 192 }
 193
 194 /*
 195  * Prepare the buffer for queueing to the DMA engine: check and set the
 196  * payload size.
 197  */
 198 static int buffer_prepare(struct vb2_buffer *vb)
 199 {
 200         struct skeleton *skel = vb2_get_drv_priv(vb->vb2_queue);
 201         unsigned long size = skel->format.sizeimage;
 202
 203         if (vb2_plane_size(vb, 0) < size) {
 204                 dev_err(&skel->pdev->dev, "buffer too small (%lu < %lu)\n",
 205                          vb2_plane_size(vb, 0), size);
 206                 return -EINVAL;
 207         }
 208
 209         vb2_set_plane_payload(vb, 0, size);
 210         return 0;
 211 }
 212
 213 /*
 214  * Queue this buffer to the DMA engine.
 215  */
 216 static void buffer_queue(struct vb2_buffer *vb)
 217 {
 218         struct skeleton *skel = vb2_get_drv_priv(vb->vb2_queue);
 219         struct skel_buffer *buf = to_skel_buffer(vb);
 220         unsigned long flags;
 221
 222         spin_lock_irqsave(&skel->qlock, flags);
 223         list_add_tail(&buf->list, &skel->buf_list);
 224
 225         /* TODO: Update any DMA pointers if necessary */
 226
 227         spin_unlock_irqrestore(&skel->qlock, flags);
 228 }
 229
 230 static void return_all_buffers(struct skeleton *skel,
 231                                enum vb2_buffer_state state)
 232 {
 233         struct skel_buffer *buf, *node;
 234         unsigned long flags;
 235
 236         spin_lock_irqsave(&skel->qlock, flags);
 237         list_for_each_entry_safe(buf, node, &skel->buf_list, list) {
 238                 vb2_buffer_done(&buf->vb, state);
 239                 list_del(&buf->list);
 240         }
 241         spin_unlock_irqrestore(&skel->qlock, flags);
 242 }
 243
 244 /*
 245  * Start streaming. First check if the minimum number of buffers have been
 246  * queued. If not, then return -ENOBUFS and the vb2 framework will call
 247  * this function again the next time a buffer has been queued until enough
 248  * buffers are available to actually start the DMA engine.
 249  */
 250 static int start_streaming(struct vb2_queue *vq, unsigned int count)
 251 {
 252         struct skeleton *skel = vb2_get_drv_priv(vq);
 253         int ret = 0;
 254
 255         skel->sequence = 0;
 256
 257         /* TODO: start DMA */
 258
 259         if (ret) {
 260                 /*
 261                  * In case of an error, return all active buffers to the
 262                  * QUEUED state
 263                  */
 264                 return_all_buffers(skel, VB2_BUF_STATE_QUEUED);
 265         }
 266         return ret;
 267 }
 268
 269 /*
 270  * Stop the DMA engine. Any remaining buffers in the DMA queue are dequeued
 271  * and passed on to the vb2 framework marked as STATE_ERROR.
 272  */
 273 static void stop_streaming(struct vb2_queue *vq)
 274 {
 275         struct skeleton *skel = vb2_get_drv_priv(vq);
 276
 277         /* TODO: stop DMA */
 278
 279         /* Release all active buffers */
 280         return_all_buffers(skel, VB2_BUF_STATE_ERROR);
 281 }
 282
 283 /*
 284  * The vb2 queue ops. Note that since q->lock is set we can use the standard
 285  * vb2_ops_wait_prepare/finish helper functions. If q->lock would be NULL,
 286  * then this driver would have to provide these ops.
 287  */
 288 static struct vb2_ops skel_qops = {
 289         .queue_setup            = queue_setup,
 290         .buf_prepare            = buffer_prepare,
 291         .buf_queue              = buffer_queue,
 292         .start_streaming        = start_streaming,
 293         .stop_streaming         = stop_streaming,
 294         .wait_prepare           = vb2_ops_wait_prepare,
 295         .wait_finish            = vb2_ops_wait_finish,
 296 };
 297
 298 /*
 299  * Required ioctl querycap. Note that the version field is prefilled with
 300  * the version of the kernel.
 301  */
 302 static int skeleton_querycap(struct file *file, void *priv,
 303                              struct v4l2_capability *cap)
 304 {
 305         struct skeleton *skel = video_drvdata(file);
 306
 307         strlcpy(cap->driver, KBUILD_MODNAME, sizeof(cap->driver));
 308         strlcpy(cap->card, "V4L2 PCI Skeleton", sizeof(cap->card));
 309         snprintf(cap->bus_info, sizeof(cap->bus_info), "PCI:%s",
 310                  pci_name(skel->pdev));
 311         return 0;
 312 }
 313
 314 /*
 315  * Helper function to check and correct struct v4l2_pix_format. It's used
 316  * not only in VIDIOC_TRY/S_FMT, but also elsewhere if changes to the SDTV
 317  * standard, HDTV timings or the video input would require updating the
 318  * current format.
 319  */
 320 static void skeleton_fill_pix_format(struct skeleton *skel,
 321                                      struct v4l2_pix_format *pix)
 322 {
 323         pix->pixelformat = V4L2_PIX_FMT_YUYV;
 324         if (skel->input == 0) {
 325                 /* S-Video input */
 326                 pix->width = 720;
 327                 pix->height = (skel->std & V4L2_STD_525_60) ? 480 : 576;
 328                 pix->field = V4L2_FIELD_INTERLACED;
 329                 pix->colorspace = V4L2_COLORSPACE_SMPTE170M;
 330         } else {
 331                 /* HDMI input */
 332                 pix->width = skel->timings.bt.width;
 333                 pix->height = skel->timings.bt.height;
 334                 if (skel->timings.bt.interlaced) {
 335                         pix->field = V4L2_FIELD_ALTERNATE;
 336                         pix->height /= 2;
 337                 } else {
 338                         pix->field = V4L2_FIELD_NONE;
 339                 }
 340                 pix->colorspace = V4L2_COLORSPACE_REC709;
 341         }
 342
 343         /*
 344          * The YUYV format is four bytes for every two pixels, so bytesperline
 345          * is width * 2.
 346          */
 347         pix->bytesperline = pix->width * 2;
 348         pix->sizeimage = pix->bytesperline * pix->height;
 349         pix->priv = 0;
 350 }
 351
 352 static int skeleton_try_fmt_vid_cap(struct file *file, void *priv,
 353                                     struct v4l2_format *f)
 354 {
 355         struct skeleton *skel = video_drvdata(file);
 356         struct v4l2_pix_format *pix = &f->fmt.pix;
 357
 358         /*
 359          * Due to historical reasons providing try_fmt with an unsupported
 360          * pixelformat will return -EINVAL for video receivers. Webcam drivers,
 361          * however, will silently correct the pixelformat. Some video capture
 362          * applications rely on this behavior...
 363          */
 364         if (pix->pixelformat != V4L2_PIX_FMT_YUYV)
 365                 return -EINVAL;
 366         skeleton_fill_pix_format(skel, pix);
 367         return 0;
 368 }
 369
 370 static int skeleton_s_fmt_vid_cap(struct file *file, void *priv,
 371                                   struct v4l2_format *f)
 372 {
 373         struct skeleton *skel = video_drvdata(file);
 374         int ret;
 375
 376         ret = skeleton_try_fmt_vid_cap(file, priv, f);
 377         if (ret)
 378                 return ret;
 379
 380         /*
 381          * It is not allowed to change the format while buffers for use with
 382          * streaming have already been allocated.
 383          */
 384         if (vb2_is_busy(&skel->queue))
 385                 return -EBUSY;
 386
 387         /* TODO: change format */
 388         skel->format = f->fmt.pix;
 389         return 0;
 390 }
 391
 392 static int skeleton_g_fmt_vid_cap(struct file *file, void *priv,
 393                                   struct v4l2_format *f)
 394 {
 395         struct skeleton *skel = video_drvdata(file);
 396
 397         f->fmt.pix = skel->format;
 398         return 0;
 399 }
 400
 401 static int skeleton_enum_fmt_vid_cap(struct file *file, void *priv,
 402                                      struct v4l2_fmtdesc *f)
 403 {
 404         if (f->index != 0)
 405                 return -EINVAL;
 406
 407         f->pixelformat = V4L2_PIX_FMT_YUYV;
 408         return 0;
 409 }
 410
 411 static int skeleton_s_std(struct file *file, void *priv, v4l2_std_id std)
 412 {
 413         struct skeleton *skel = video_drvdata(file);
 414
 415         /* S_STD is not supported on the HDMI input */
 416         if (skel->input)
 417                 return -ENODATA;
 418
 419         /*
 420          * No change, so just return. Some applications call S_STD again after
 421          * the buffers for streaming have been set up, so we have to allow for
 422          * this behavior.
 423          */
 424         if (std == skel->std)
 425                 return 0;
 426
 427         /*
 428          * Changing the standard implies a format change, which is not allowed
 429          * while buffers for use with streaming have already been allocated.
 430          */
 431         if (vb2_is_busy(&skel->queue))
 432                 return -EBUSY;
 433
 434         /* TODO: handle changing std */
 435
 436         skel->std = std;
 437
 438         /* Update the internal format */
 439         skeleton_fill_pix_format(skel, &skel->format);
 440         return 0;
 441 }
 442
 443 static int skeleton_g_std(struct file *file, void *priv, v4l2_std_id *std)
 444 {
 445         struct skeleton *skel = video_drvdata(file);
 446
 447         /* G_STD is not supported on the HDMI input */
 448         if (skel->input)
 449                 return -ENODATA;
 450
 451         *std = skel->std;
 452         return 0;
 453 }
 454
 455 /*
 456  * Query the current standard as seen by the hardware. This function shall
 457  * never actually change the standard, it just detects and reports.
 458  * The framework will initially set *std to tvnorms (i.e. the set of
 459  * supported standards by this input), and this function should just AND
 460  * this value. If there is no signal, then *std should be set to 0.
 461  */
 462 static int skeleton_querystd(struct file *file, void *priv, v4l2_std_id *std)
 463 {
 464         struct skeleton *skel = video_drvdata(file);
 465
 466         /* QUERY_STD is not supported on the HDMI input */
 467         if (skel->input)
 468                 return -ENODATA;
 469
 470 #ifdef TODO
 471         /*
 472          * Query currently seen standard. Initial value of *std is
 473          * V4L2_STD_ALL. This function should look something like this:
 474          */
 475         get_signal_info();
 476         if (no_signal) {
 477                 *std = 0;
 478                 return 0;
 479         }
 480         /* Use signal information to reduce the number of possible standards */
 481         if (signal_has_525_lines)
 482                 *std &= V4L2_STD_525_60;
 483         else
 484                 *std &= V4L2_STD_625_50;
 485 #endif
 486         return 0;
 487 }
 488
 489 static int skeleton_s_dv_timings(struct file *file, void *_fh,
 490                                  struct v4l2_dv_timings *timings)
 491 {
 492         struct skeleton *skel = video_drvdata(file);
 493
 494         /* S_DV_TIMINGS is not supported on the S-Video input */
 495         if (skel->input == 0)
 496                 return -ENODATA;
 497
 498         /* Quick sanity check */
 499         if (!v4l2_valid_dv_timings(timings, &skel_timings_cap, NULL, NULL))
 500                 return -EINVAL;
 501
 502         /* Check if the timings are part of the CEA-861 timings. */
 503         if (!v4l2_find_dv_timings_cap(timings, &skel_timings_cap,
 504                                       0, NULL, NULL))
 505                 return -EINVAL;
 506
 507         /* Return 0 if the new timings are the same as the current timings. */
 508         if (v4l2_match_dv_timings(timings, &skel->timings, 0, false))
 509                 return 0;
 510
 511         /*
 512          * Changing the timings implies a format change, which is not allowed
 513          * while buffers for use with streaming have already been allocated.
 514          */
 515         if (vb2_is_busy(&skel->queue))
 516                 return -EBUSY;
 517
 518         /* TODO: Configure new timings */
 519
 520         /* Save timings */
 521         skel->timings = *timings;
 522
 523         /* Update the internal format */
 524         skeleton_fill_pix_format(skel, &skel->format);
 525         return 0;
 526 }
 527
 528 static int skeleton_g_dv_timings(struct file *file, void *_fh,
 529                                  struct v4l2_dv_timings *timings)
 530 {
 531         struct skeleton *skel = video_drvdata(file);
 532
 533         /* G_DV_TIMINGS is not supported on the S-Video input */
 534         if (skel->input == 0)
 535                 return -ENODATA;
 536
 537         *timings = skel->timings;
 538         return 0;
 539 }
 540
 541 static int skeleton_enum_dv_timings(struct file *file, void *_fh,
 542                                     struct v4l2_enum_dv_timings *timings)
 543 {
 544         struct skeleton *skel = video_drvdata(file);
 545
 546         /* ENUM_DV_TIMINGS is not supported on the S-Video input */
 547         if (skel->input == 0)
 548                 return -ENODATA;
 549
 550         return v4l2_enum_dv_timings_cap(timings, &skel_timings_cap,
 551                                         NULL, NULL);
 552 }
 553
 554 /*
 555  * Query the current timings as seen by the hardware. This function shall
 556  * never actually change the timings, it just detects and reports.
 557  * If no signal is detected, then return -ENOLINK. If the hardware cannot
 558  * lock to the signal, then return -ENOLCK. If the signal is out of range
 559  * of the capabilities of the system (e.g., it is possible that the receiver
 560  * can lock but that the DMA engine it is connected to cannot handle
 561  * pixelclocks above a certain frequency), then -ERANGE is returned.
 562  */
 563 static int skeleton_query_dv_timings(struct file *file, void *_fh,
 564                                      struct v4l2_dv_timings *timings)
 565 {
 566         struct skeleton *skel = video_drvdata(file);
 567
 568         /* QUERY_DV_TIMINGS is not supported on the S-Video input */
 569         if (skel->input == 0)
 570                 return -ENODATA;
 571
 572 #ifdef TODO
 573         /*
 574          * Query currently seen timings. This function should look
 575          * something like this:
 576          */
 577         detect_timings();
 578         if (no_signal)
 579                 return -ENOLINK;
 580         if (cannot_lock_to_signal)
 581                 return -ENOLCK;
 582         if (signal_out_of_range_of_capabilities)
 583                 return -ERANGE;
 584
 585         /* Useful for debugging */
 586         v4l2_print_dv_timings(skel->v4l2_dev.name, "query_dv_timings:",
 587                         timings, true);
 588 #endif
 589         return 0;
 590 }
 591
 592 static int skeleton_dv_timings_cap(struct file *file, void *fh,
 593                                    struct v4l2_dv_timings_cap *cap)
 594 {
 595         struct skeleton *skel = video_drvdata(file);
 596
 597         /* DV_TIMINGS_CAP is not supported on the S-Video input */
 598         if (skel->input == 0)
 599                 return -ENODATA;
 600         *cap = skel_timings_cap;
 601         return 0;
 602 }
 603
 604 static int skeleton_enum_input(struct file *file, void *priv,
 605                                struct v4l2_input *i)
 606 {
 607         if (i->index > 1)
 608                 return -EINVAL;
 609
 610         i->type = V4L2_INPUT_TYPE_CAMERA;
 611         if (i->index == 0) {
 612                 i->std = SKEL_TVNORMS;
 613                 strlcpy(i->name, "S-Video", sizeof(i->name));
 614                 i->capabilities = V4L2_IN_CAP_STD;
 615         } else {
 616                 i->std = 0;
 617                 strlcpy(i->name, "HDMI", sizeof(i->name));
 618                 i->capabilities = V4L2_IN_CAP_DV_TIMINGS;
 619         }
 620         return 0;
 621 }
 622
 623 static int skeleton_s_input(struct file *file, void *priv, unsigned int i)
 624 {
 625         struct skeleton *skel = video_drvdata(file);
 626
 627         if (i > 1)
 628                 return -EINVAL;
 629
 630         /*
 631          * Changing the input implies a format change, which is not allowed
 632          * while buffers for use with streaming have already been allocated.
 633          */
 634         if (vb2_is_busy(&skel->queue))
 635                 return -EBUSY;
 636
 637         skel->input = i;
 638         /*
 639          * Update tvnorms. The tvnorms value is used by the core to implement
 640          * VIDIOC_ENUMSTD so it has to be correct. If tvnorms == 0, then
 641          * ENUMSTD will return -ENODATA.
 642          */
 643         skel->vdev.tvnorms = i ? 0 : SKEL_TVNORMS;
 644
 645         /* Update the internal format */
 646         skeleton_fill_pix_format(skel, &skel->format);
 647         return 0;
 648 }
 649
 650 static int skeleton_g_input(struct file *file, void *priv, unsigned int *i)
 651 {
 652         struct skeleton *skel = video_drvdata(file);
 653
 654         *i = skel->input;
 655         return 0;
 656 }
 657
 658 /* The control handler. */
 659 static int skeleton_s_ctrl(struct v4l2_ctrl *ctrl)
 660 {
 661         /*struct skeleton *skel =
 662                 container_of(ctrl->handler, struct skeleton, ctrl_handler);*/
 663
 664         switch (ctrl->id) {
 665         case V4L2_CID_BRIGHTNESS:
 666                 /* TODO: set brightness to ctrl->val */
 667                 break;
 668         case V4L2_CID_CONTRAST:
 669                 /* TODO: set contrast to ctrl->val */
 670                 break;
 671         case V4L2_CID_SATURATION:
 672                 /* TODO: set saturation to ctrl->val */
 673                 break;
 674         case V4L2_CID_HUE:
 675                 /* TODO: set hue to ctrl->val */
 676                 break;
 677         default:
 678                 return -EINVAL;
 679         }
 680         return 0;
 681 }
 682
 683 /* ------------------------------------------------------------------
 684         File operations for the device
 685    ------------------------------------------------------------------*/
 686
 687 static const struct v4l2_ctrl_ops skel_ctrl_ops = {
 688         .s_ctrl = skeleton_s_ctrl,
 689 };
 690
 691 /*
 692  * The set of all supported ioctls. Note that all the streaming ioctls
 693  * use the vb2 helper functions that take care of all the locking and
 694  * that also do ownership tracking (i.e. only the filehandle that requested
 695  * the buffers can call the streaming ioctls, all other filehandles will
 696  * receive -EBUSY if they attempt to call the same streaming ioctls).
 697  *
 698  * The last three ioctls also use standard helper functions: these implement
 699  * standard behavior for drivers with controls.
 700  */
 701 static const struct v4l2_ioctl_ops skel_ioctl_ops = {
 702         .vidioc_querycap = skeleton_querycap,
 703         .vidioc_try_fmt_vid_cap = skeleton_try_fmt_vid_cap,
 704         .vidioc_s_fmt_vid_cap = skeleton_s_fmt_vid_cap,
 705         .vidioc_g_fmt_vid_cap = skeleton_g_fmt_vid_cap,
 706         .vidioc_enum_fmt_vid_cap = skeleton_enum_fmt_vid_cap,
 707
 708         .vidioc_g_std = skeleton_g_std,
 709         .vidioc_s_std = skeleton_s_std,
 710         .vidioc_querystd = skeleton_querystd,
 711
 712         .vidioc_s_dv_timings = skeleton_s_dv_timings,
 713         .vidioc_g_dv_timings = skeleton_g_dv_timings,
 714         .vidioc_enum_dv_timings = skeleton_enum_dv_timings,
 715         .vidioc_query_dv_timings = skeleton_query_dv_timings,
 716         .vidioc_dv_timings_cap = skeleton_dv_timings_cap,
 717
 718         .vidioc_enum_input = skeleton_enum_input,
 719         .vidioc_g_input = skeleton_g_input,
 720         .vidioc_s_input = skeleton_s_input,
 721
 722         .vidioc_reqbufs = vb2_ioctl_reqbufs,
 723         .vidioc_create_bufs = vb2_ioctl_create_bufs,
 724         .vidioc_querybuf = vb2_ioctl_querybuf,
 725         .vidioc_qbuf = vb2_ioctl_qbuf,
 726         .vidioc_dqbuf = vb2_ioctl_dqbuf,
 727         .vidioc_expbuf = vb2_ioctl_expbuf,
 728         .vidioc_streamon = vb2_ioctl_streamon,
 729         .vidioc_streamoff = vb2_ioctl_streamoff,
 730
 731         .vidioc_log_status = v4l2_ctrl_log_status,
 732         .vidioc_subscribe_event = v4l2_ctrl_subscribe_event,
 733         .vidioc_unsubscribe_event = v4l2_event_unsubscribe,
 734 };
 735
 736 /*
 737  * The set of file operations. Note that all these ops are standard core
 738  * helper functions.
 739  */
 740 static const struct v4l2_file_operations skel_fops = {
 741         .owner = THIS_MODULE,
 742         .open = v4l2_fh_open,
 743         .release = vb2_fop_release,
 744         .unlocked_ioctl = video_ioctl2,
 745         .read = vb2_fop_read,
 746         .mmap = vb2_fop_mmap,
 747         .poll = vb2_fop_poll,
 748 };
 749
 750 /*
 751  * The initial setup of this device instance. Note that the initial state of
 752  * the driver should be complete. So the initial format, standard, timings
 753  * and video input should all be initialized to some reasonable value.
 754  */
 755 static int skeleton_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 756 {
 757         /* The initial timings are chosen to be 720p60. */
 758         static const struct v4l2_dv_timings timings_def =
 759                 V4L2_DV_BT_CEA_1280X720P60;
 760         struct skeleton *skel;
 761         struct video_device *vdev;
 762         struct v4l2_ctrl_handler *hdl;
 763         struct vb2_queue *q;
 764         int ret;
 765
 766         /* Enable PCI */
 767         ret = pci_enable_device(pdev);
 768         if (ret)
 769                 return ret;
 770         ret = pci_set_dma_mask(pdev, DMA_BIT_MASK(32));
 771         if (ret) {
 772                 dev_err(&pdev->dev, "no suitable DMA available.\n");
 773                 goto disable_pci;
 774         }
 775
 776         /* Allocate a new instance */
 777         skel = devm_kzalloc(&pdev->dev, sizeof(struct skeleton), GFP_KERNEL);
 778         if (!skel)
 779                 return -ENOMEM;
 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->drv_priv = skel;
 824         q->buf_struct_size = sizeof(struct skel_buffer);
 825         q->ops = &skel_qops;
 826         q->mem_ops = &vb2_dma_contig_memops;
 827         q->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
 828         /*
 829          * Assume that this DMA engine needs to have at least two buffers
 830          * available before it can be started. The start_streaming() op
 831          * won't be called until at least this many buffers are queued up.
 832          */
 833         q->min_buffers_needed = 2;
 834         /*
 835          * The serialization lock for the streaming ioctls. This is the same
 836          * as the main serialization lock, but if some of the non-streaming
 837          * ioctls could take a long time to execute, then you might want to
 838          * have a different lock here to prevent VIDIOC_DQBUF from being
 839          * blocked while waiting for another action to finish. This is
 840          * generally not needed for PCI devices, but USB devices usually do
 841          * want a separate lock here.
 842          */
 843         q->lock = &skel->lock;
 844         /*
 845          * Since this driver can only do 32-bit DMA we must make sure that
 846          * the vb2 core will allocate the buffers in 32-bit DMA memory.
 847          */
 848         q->gfp_flags = GFP_DMA32;
 849         ret = vb2_queue_init(q);
 850         if (ret)
 851                 goto free_hdl;
 852
 853         skel->alloc_ctx = vb2_dma_contig_init_ctx(&pdev->dev);
 854         if (IS_ERR(skel->alloc_ctx)) {
 855                 dev_err(&pdev->dev, "Can't allocate buffer context");
 856                 ret = PTR_ERR(skel->alloc_ctx);
 857                 goto free_hdl;
 858         }
 859         INIT_LIST_HEAD(&skel->buf_list);
 860         spin_lock_init(&skel->qlock);
 861
 862         /* Initialize the video_device structure */
 863         vdev = &skel->vdev;
 864         strlcpy(vdev->name, KBUILD_MODNAME, sizeof(vdev->name));
 865         /*
 866          * There is nothing to clean up, so release is set to an empty release
 867          * function. The release callback must be non-NULL.
 868          */
 869         vdev->release = video_device_release_empty;
 870         vdev->fops = &skel_fops,
 871         vdev->ioctl_ops = &skel_ioctl_ops,
 872         vdev->device_caps = V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_READWRITE |
 873                             V4L2_CAP_STREAMING;
 874         /*
 875          * The main serialization lock. All ioctls are serialized by this
 876          * lock. Exception: if q->lock is set, then the streaming ioctls
 877          * are serialized by that separate lock.
 878          */
 879         vdev->lock = &skel->lock;
 880         vdev->queue = q;
 881         vdev->v4l2_dev = &skel->v4l2_dev;
 882         /* Supported SDTV standards, if any */
 883         vdev->tvnorms = SKEL_TVNORMS;
 884         video_set_drvdata(vdev, skel);
 885
 886         ret = video_register_device(vdev, VFL_TYPE_GRABBER, -1);
 887         if (ret)
 888                 goto free_ctx;
 889
 890         dev_info(&pdev->dev, "V4L2 PCI Skeleton Driver loaded\n");
 891         return 0;
 892
 893 free_ctx:
 894         vb2_dma_contig_cleanup_ctx(skel->alloc_ctx);
 895 free_hdl:
 896         v4l2_ctrl_handler_free(&skel->ctrl_handler);
 897         v4l2_device_unregister(&skel->v4l2_dev);
 898 disable_pci:
 899         pci_disable_device(pdev);
 900         return ret;
 901 }
 902
 903 static void skeleton_remove(struct pci_dev *pdev)
 904 {
 905         struct v4l2_device *v4l2_dev = pci_get_drvdata(pdev);
 906         struct skeleton *skel = container_of(v4l2_dev, struct skeleton, v4l2_dev);
 907
 908         video_unregister_device(&skel->vdev);
 909         v4l2_ctrl_handler_free(&skel->ctrl_handler);
 910         vb2_dma_contig_cleanup_ctx(skel->alloc_ctx);
 911         v4l2_device_unregister(&skel->v4l2_dev);
 912         pci_disable_device(skel->pdev);
 913 }
 914
 915 static struct pci_driver skeleton_driver = {
 916         .name = KBUILD_MODNAME,
 917         .probe = skeleton_probe,
 918         .remove = skeleton_remove,
 919         .id_table = skeleton_pci_tbl,
 920 };
 921
 922 module_pci_driver(skeleton_driver);