root/samples/v4l/v4l2-pci-skeleton.c

DEFINITIONS

1. to_skel_buffer
2. skeleton_irq
3. queue_setup
4. buffer_prepare
5. buffer_queue
6. return_all_buffers
7. start_streaming
8. stop_streaming
9. skeleton_querycap
10. skeleton_fill_pix_format
11. skeleton_try_fmt_vid_cap
12. skeleton_s_fmt_vid_cap
13. skeleton_g_fmt_vid_cap
14. skeleton_enum_fmt_vid_cap
15. skeleton_s_std
16. skeleton_g_std
17. skeleton_querystd
18. skeleton_s_dv_timings
19. skeleton_g_dv_timings
20. skeleton_enum_dv_timings
21. skeleton_query_dv_timings
22. skeleton_dv_timings_cap
23. skeleton_enum_input
24. skeleton_s_input
25. skeleton_g_input
26. skeleton_s_ctrl
27. skeleton_probe
28. skeleton_remove

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