2 * This is a V4L2 PCI Skeleton Driver. It gives an initial skeleton source
3 * for use with other PCI drivers.
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.
8 * Copyright 2014 Cisco Systems, Inc. and/or its affiliates. All rights reserved.
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.
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
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>
43 MODULE_DESCRIPTION("V4L2 PCI Skeleton Driver");
44 MODULE_AUTHOR("Hans Verkuil");
45 MODULE_LICENSE("GPL v2");
48 * struct skeleton - All internal data for one instance of device
50 * @v4l2_dev: top-level v4l2 device struct
51 * @vdev: video node structure
52 * @ctrl_handler: control handler structure
53 * @lock: ioctl serialization mutex
54 * @std: current SDTV standard
55 * @timings: current HDTV timings
56 * @format: current pix format
57 * @input: current video input (0 = SDTV, 1 = HDTV)
58 * @queue: vb2 video capture queue
59 * @qlock: spinlock controlling access to buf_list and sequence
60 * @buf_list: list of buffers queued for DMA
61 * @sequence: frame sequence counter
65 struct v4l2_device v4l2_dev;
66 struct video_device vdev;
67 struct v4l2_ctrl_handler ctrl_handler;
70 struct v4l2_dv_timings timings;
71 struct v4l2_pix_format format;
74 struct vb2_queue queue;
77 struct list_head buf_list;
83 struct vb2_v4l2_buffer vb;
84 struct list_head list;
87 static inline struct skel_buffer *to_skel_buffer(struct vb2_v4l2_buffer *vbuf)
89 return container_of(vbuf, struct skel_buffer, vb);
92 static const struct pci_device_id skeleton_pci_tbl[] = {
93 /* { PCI_DEVICE(PCI_VENDOR_ID_, PCI_DEVICE_ID_) }, */
96 MODULE_DEVICE_TABLE(pci, skeleton_pci_tbl);
99 * HDTV: this structure has the capabilities of the HDTV receiver.
100 * It is used to constrain the huge list of possible formats based
101 * upon the hardware capabilities.
103 static const struct v4l2_dv_timings_cap skel_timings_cap = {
104 .type = V4L2_DV_BT_656_1120,
105 /* keep this initialization for compatibility with GCC < 4.4.6 */
107 V4L2_INIT_BT_TIMINGS(
108 720, 1920, /* min/max width */
109 480, 1080, /* min/max height */
110 27000000, 74250000, /* min/max pixelclock*/
111 V4L2_DV_BT_STD_CEA861, /* Supported standards */
113 V4L2_DV_BT_CAP_INTERLACED | V4L2_DV_BT_CAP_PROGRESSIVE
118 * Supported SDTV standards. This does the same job as skel_timings_cap, but
119 * for standard TV formats.
121 #define SKEL_TVNORMS V4L2_STD_ALL
124 * Interrupt handler: typically interrupts happen after a new frame has been
125 * captured. It is the job of the handler to remove the new frame from the
126 * internal list and give it back to the vb2 framework, updating the sequence
127 * counter, field and timestamp at the same time.
129 static irqreturn_t skeleton_irq(int irq, void *dev_id)
132 struct skeleton *skel = dev_id;
134 /* handle interrupt */
136 /* Once a new frame has been captured, mark it as done like this: */
137 if (captured_new_frame) {
139 spin_lock(&skel->qlock);
140 list_del(&new_buf->list);
141 spin_unlock(&skel->qlock);
142 new_buf->vb.vb2_buf.timestamp = ktime_get_ns();
143 new_buf->vb.sequence = skel->sequence++;
144 new_buf->vb.field = skel->field;
145 if (skel->format.field == V4L2_FIELD_ALTERNATE) {
146 if (skel->field == V4L2_FIELD_BOTTOM)
147 skel->field = V4L2_FIELD_TOP;
148 else if (skel->field == V4L2_FIELD_TOP)
149 skel->field = V4L2_FIELD_BOTTOM;
151 vb2_buffer_done(&new_buf->vb.vb2_buf, VB2_BUF_STATE_DONE);
158 * Setup the constraints of the queue: besides setting the number of planes
159 * per buffer and the size and allocation context of each plane, it also
160 * checks if sufficient buffers have been allocated. Usually 3 is a good
161 * minimum number: many DMA engines need a minimum of 2 buffers in the
162 * queue and you need to have another available for userspace processing.
164 static int queue_setup(struct vb2_queue *vq,
165 unsigned int *nbuffers, unsigned int *nplanes,
166 unsigned int sizes[], struct device *alloc_devs[])
168 struct skeleton *skel = vb2_get_drv_priv(vq);
170 skel->field = skel->format.field;
171 if (skel->field == V4L2_FIELD_ALTERNATE) {
173 * You cannot use read() with FIELD_ALTERNATE since the field
174 * information (TOP/BOTTOM) cannot be passed back to the user.
176 if (vb2_fileio_is_active(vq))
178 skel->field = V4L2_FIELD_TOP;
181 if (vq->num_buffers + *nbuffers < 3)
182 *nbuffers = 3 - vq->num_buffers;
185 return sizes[0] < skel->format.sizeimage ? -EINVAL : 0;
187 sizes[0] = skel->format.sizeimage;
192 * Prepare the buffer for queueing to the DMA engine: check and set the
195 static int buffer_prepare(struct vb2_buffer *vb)
197 struct skeleton *skel = vb2_get_drv_priv(vb->vb2_queue);
198 unsigned long size = skel->format.sizeimage;
200 if (vb2_plane_size(vb, 0) < size) {
201 dev_err(&skel->pdev->dev, "buffer too small (%lu < %lu)\n",
202 vb2_plane_size(vb, 0), size);
206 vb2_set_plane_payload(vb, 0, size);
211 * Queue this buffer to the DMA engine.
213 static void buffer_queue(struct vb2_buffer *vb)
215 struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
216 struct skeleton *skel = vb2_get_drv_priv(vb->vb2_queue);
217 struct skel_buffer *buf = to_skel_buffer(vbuf);
220 spin_lock_irqsave(&skel->qlock, flags);
221 list_add_tail(&buf->list, &skel->buf_list);
223 /* TODO: Update any DMA pointers if necessary */
225 spin_unlock_irqrestore(&skel->qlock, flags);
228 static void return_all_buffers(struct skeleton *skel,
229 enum vb2_buffer_state state)
231 struct skel_buffer *buf, *node;
234 spin_lock_irqsave(&skel->qlock, flags);
235 list_for_each_entry_safe(buf, node, &skel->buf_list, list) {
236 vb2_buffer_done(&buf->vb.vb2_buf, state);
237 list_del(&buf->list);
239 spin_unlock_irqrestore(&skel->qlock, flags);
243 * Start streaming. First check if the minimum number of buffers have been
244 * queued. If not, then return -ENOBUFS and the vb2 framework will call
245 * this function again the next time a buffer has been queued until enough
246 * buffers are available to actually start the DMA engine.
248 static int start_streaming(struct vb2_queue *vq, unsigned int count)
250 struct skeleton *skel = vb2_get_drv_priv(vq);
255 /* TODO: start DMA */
259 * In case of an error, return all active buffers to the
262 return_all_buffers(skel, VB2_BUF_STATE_QUEUED);
268 * Stop the DMA engine. Any remaining buffers in the DMA queue are dequeued
269 * and passed on to the vb2 framework marked as STATE_ERROR.
271 static void stop_streaming(struct vb2_queue *vq)
273 struct skeleton *skel = vb2_get_drv_priv(vq);
277 /* Release all active buffers */
278 return_all_buffers(skel, VB2_BUF_STATE_ERROR);
282 * The vb2 queue ops. Note that since q->lock is set we can use the standard
283 * vb2_ops_wait_prepare/finish helper functions. If q->lock would be NULL,
284 * then this driver would have to provide these ops.
286 static const struct vb2_ops skel_qops = {
287 .queue_setup = queue_setup,
288 .buf_prepare = buffer_prepare,
289 .buf_queue = buffer_queue,
290 .start_streaming = start_streaming,
291 .stop_streaming = stop_streaming,
292 .wait_prepare = vb2_ops_wait_prepare,
293 .wait_finish = vb2_ops_wait_finish,
297 * Required ioctl querycap. Note that the version field is prefilled with
298 * the version of the kernel.
300 static int skeleton_querycap(struct file *file, void *priv,
301 struct v4l2_capability *cap)
303 struct skeleton *skel = video_drvdata(file);
305 strlcpy(cap->driver, KBUILD_MODNAME, sizeof(cap->driver));
306 strlcpy(cap->card, "V4L2 PCI Skeleton", sizeof(cap->card));
307 snprintf(cap->bus_info, sizeof(cap->bus_info), "PCI:%s",
308 pci_name(skel->pdev));
313 * Helper function to check and correct struct v4l2_pix_format. It's used
314 * not only in VIDIOC_TRY/S_FMT, but also elsewhere if changes to the SDTV
315 * standard, HDTV timings or the video input would require updating the
318 static void skeleton_fill_pix_format(struct skeleton *skel,
319 struct v4l2_pix_format *pix)
321 pix->pixelformat = V4L2_PIX_FMT_YUYV;
322 if (skel->input == 0) {
325 pix->height = (skel->std & V4L2_STD_525_60) ? 480 : 576;
326 pix->field = V4L2_FIELD_INTERLACED;
327 pix->colorspace = V4L2_COLORSPACE_SMPTE170M;
330 pix->width = skel->timings.bt.width;
331 pix->height = skel->timings.bt.height;
332 if (skel->timings.bt.interlaced) {
333 pix->field = V4L2_FIELD_ALTERNATE;
336 pix->field = V4L2_FIELD_NONE;
338 pix->colorspace = V4L2_COLORSPACE_REC709;
342 * The YUYV format is four bytes for every two pixels, so bytesperline
345 pix->bytesperline = pix->width * 2;
346 pix->sizeimage = pix->bytesperline * pix->height;
350 static int skeleton_try_fmt_vid_cap(struct file *file, void *priv,
351 struct v4l2_format *f)
353 struct skeleton *skel = video_drvdata(file);
354 struct v4l2_pix_format *pix = &f->fmt.pix;
357 * Due to historical reasons providing try_fmt with an unsupported
358 * pixelformat will return -EINVAL for video receivers. Webcam drivers,
359 * however, will silently correct the pixelformat. Some video capture
360 * applications rely on this behavior...
362 if (pix->pixelformat != V4L2_PIX_FMT_YUYV)
364 skeleton_fill_pix_format(skel, pix);
368 static int skeleton_s_fmt_vid_cap(struct file *file, void *priv,
369 struct v4l2_format *f)
371 struct skeleton *skel = video_drvdata(file);
374 ret = skeleton_try_fmt_vid_cap(file, priv, f);
379 * It is not allowed to change the format while buffers for use with
380 * streaming have already been allocated.
382 if (vb2_is_busy(&skel->queue))
385 /* TODO: change format */
386 skel->format = f->fmt.pix;
390 static int skeleton_g_fmt_vid_cap(struct file *file, void *priv,
391 struct v4l2_format *f)
393 struct skeleton *skel = video_drvdata(file);
395 f->fmt.pix = skel->format;
399 static int skeleton_enum_fmt_vid_cap(struct file *file, void *priv,
400 struct v4l2_fmtdesc *f)
405 f->pixelformat = V4L2_PIX_FMT_YUYV;
409 static int skeleton_s_std(struct file *file, void *priv, v4l2_std_id std)
411 struct skeleton *skel = video_drvdata(file);
413 /* S_STD is not supported on the HDMI input */
418 * No change, so just return. Some applications call S_STD again after
419 * the buffers for streaming have been set up, so we have to allow for
422 if (std == skel->std)
426 * Changing the standard implies a format change, which is not allowed
427 * while buffers for use with streaming have already been allocated.
429 if (vb2_is_busy(&skel->queue))
432 /* TODO: handle changing std */
436 /* Update the internal format */
437 skeleton_fill_pix_format(skel, &skel->format);
441 static int skeleton_g_std(struct file *file, void *priv, v4l2_std_id *std)
443 struct skeleton *skel = video_drvdata(file);
445 /* G_STD is not supported on the HDMI input */
454 * Query the current standard as seen by the hardware. This function shall
455 * never actually change the standard, it just detects and reports.
456 * The framework will initially set *std to tvnorms (i.e. the set of
457 * supported standards by this input), and this function should just AND
458 * this value. If there is no signal, then *std should be set to 0.
460 static int skeleton_querystd(struct file *file, void *priv, v4l2_std_id *std)
462 struct skeleton *skel = video_drvdata(file);
464 /* QUERY_STD is not supported on the HDMI input */
470 * Query currently seen standard. Initial value of *std is
471 * V4L2_STD_ALL. This function should look something like this:
478 /* Use signal information to reduce the number of possible standards */
479 if (signal_has_525_lines)
480 *std &= V4L2_STD_525_60;
482 *std &= V4L2_STD_625_50;
487 static int skeleton_s_dv_timings(struct file *file, void *_fh,
488 struct v4l2_dv_timings *timings)
490 struct skeleton *skel = video_drvdata(file);
492 /* S_DV_TIMINGS is not supported on the S-Video input */
493 if (skel->input == 0)
496 /* Quick sanity check */
497 if (!v4l2_valid_dv_timings(timings, &skel_timings_cap, NULL, NULL))
500 /* Check if the timings are part of the CEA-861 timings. */
501 if (!v4l2_find_dv_timings_cap(timings, &skel_timings_cap,
505 /* Return 0 if the new timings are the same as the current timings. */
506 if (v4l2_match_dv_timings(timings, &skel->timings, 0, false))
510 * Changing the timings implies a format change, which is not allowed
511 * while buffers for use with streaming have already been allocated.
513 if (vb2_is_busy(&skel->queue))
516 /* TODO: Configure new timings */
519 skel->timings = *timings;
521 /* Update the internal format */
522 skeleton_fill_pix_format(skel, &skel->format);
526 static int skeleton_g_dv_timings(struct file *file, void *_fh,
527 struct v4l2_dv_timings *timings)
529 struct skeleton *skel = video_drvdata(file);
531 /* G_DV_TIMINGS is not supported on the S-Video input */
532 if (skel->input == 0)
535 *timings = skel->timings;
539 static int skeleton_enum_dv_timings(struct file *file, void *_fh,
540 struct v4l2_enum_dv_timings *timings)
542 struct skeleton *skel = video_drvdata(file);
544 /* ENUM_DV_TIMINGS is not supported on the S-Video input */
545 if (skel->input == 0)
548 return v4l2_enum_dv_timings_cap(timings, &skel_timings_cap,
553 * Query the current timings as seen by the hardware. This function shall
554 * never actually change the timings, it just detects and reports.
555 * If no signal is detected, then return -ENOLINK. If the hardware cannot
556 * lock to the signal, then return -ENOLCK. If the signal is out of range
557 * of the capabilities of the system (e.g., it is possible that the receiver
558 * can lock but that the DMA engine it is connected to cannot handle
559 * pixelclocks above a certain frequency), then -ERANGE is returned.
561 static int skeleton_query_dv_timings(struct file *file, void *_fh,
562 struct v4l2_dv_timings *timings)
564 struct skeleton *skel = video_drvdata(file);
566 /* QUERY_DV_TIMINGS is not supported on the S-Video input */
567 if (skel->input == 0)
572 * Query currently seen timings. This function should look
573 * something like this:
578 if (cannot_lock_to_signal)
580 if (signal_out_of_range_of_capabilities)
583 /* Useful for debugging */
584 v4l2_print_dv_timings(skel->v4l2_dev.name, "query_dv_timings:",
590 static int skeleton_dv_timings_cap(struct file *file, void *fh,
591 struct v4l2_dv_timings_cap *cap)
593 struct skeleton *skel = video_drvdata(file);
595 /* DV_TIMINGS_CAP is not supported on the S-Video input */
596 if (skel->input == 0)
598 *cap = skel_timings_cap;
602 static int skeleton_enum_input(struct file *file, void *priv,
603 struct v4l2_input *i)
608 i->type = V4L2_INPUT_TYPE_CAMERA;
610 i->std = SKEL_TVNORMS;
611 strlcpy(i->name, "S-Video", sizeof(i->name));
612 i->capabilities = V4L2_IN_CAP_STD;
615 strlcpy(i->name, "HDMI", sizeof(i->name));
616 i->capabilities = V4L2_IN_CAP_DV_TIMINGS;
621 static int skeleton_s_input(struct file *file, void *priv, unsigned int i)
623 struct skeleton *skel = video_drvdata(file);
629 * Changing the input implies a format change, which is not allowed
630 * while buffers for use with streaming have already been allocated.
632 if (vb2_is_busy(&skel->queue))
637 * Update tvnorms. The tvnorms value is used by the core to implement
638 * VIDIOC_ENUMSTD so it has to be correct. If tvnorms == 0, then
639 * ENUMSTD will return -ENODATA.
641 skel->vdev.tvnorms = i ? 0 : SKEL_TVNORMS;
643 /* Update the internal format */
644 skeleton_fill_pix_format(skel, &skel->format);
648 static int skeleton_g_input(struct file *file, void *priv, unsigned int *i)
650 struct skeleton *skel = video_drvdata(file);
656 /* The control handler. */
657 static int skeleton_s_ctrl(struct v4l2_ctrl *ctrl)
659 /*struct skeleton *skel =
660 container_of(ctrl->handler, struct skeleton, ctrl_handler);*/
663 case V4L2_CID_BRIGHTNESS:
664 /* TODO: set brightness to ctrl->val */
666 case V4L2_CID_CONTRAST:
667 /* TODO: set contrast to ctrl->val */
669 case V4L2_CID_SATURATION:
670 /* TODO: set saturation to ctrl->val */
673 /* TODO: set hue to ctrl->val */
681 /* ------------------------------------------------------------------
682 File operations for the device
683 ------------------------------------------------------------------*/
685 static const struct v4l2_ctrl_ops skel_ctrl_ops = {
686 .s_ctrl = skeleton_s_ctrl,
690 * The set of all supported ioctls. Note that all the streaming ioctls
691 * use the vb2 helper functions that take care of all the locking and
692 * that also do ownership tracking (i.e. only the filehandle that requested
693 * the buffers can call the streaming ioctls, all other filehandles will
694 * receive -EBUSY if they attempt to call the same streaming ioctls).
696 * The last three ioctls also use standard helper functions: these implement
697 * standard behavior for drivers with controls.
699 static const struct v4l2_ioctl_ops skel_ioctl_ops = {
700 .vidioc_querycap = skeleton_querycap,
701 .vidioc_try_fmt_vid_cap = skeleton_try_fmt_vid_cap,
702 .vidioc_s_fmt_vid_cap = skeleton_s_fmt_vid_cap,
703 .vidioc_g_fmt_vid_cap = skeleton_g_fmt_vid_cap,
704 .vidioc_enum_fmt_vid_cap = skeleton_enum_fmt_vid_cap,
706 .vidioc_g_std = skeleton_g_std,
707 .vidioc_s_std = skeleton_s_std,
708 .vidioc_querystd = skeleton_querystd,
710 .vidioc_s_dv_timings = skeleton_s_dv_timings,
711 .vidioc_g_dv_timings = skeleton_g_dv_timings,
712 .vidioc_enum_dv_timings = skeleton_enum_dv_timings,
713 .vidioc_query_dv_timings = skeleton_query_dv_timings,
714 .vidioc_dv_timings_cap = skeleton_dv_timings_cap,
716 .vidioc_enum_input = skeleton_enum_input,
717 .vidioc_g_input = skeleton_g_input,
718 .vidioc_s_input = skeleton_s_input,
720 .vidioc_reqbufs = vb2_ioctl_reqbufs,
721 .vidioc_create_bufs = vb2_ioctl_create_bufs,
722 .vidioc_querybuf = vb2_ioctl_querybuf,
723 .vidioc_qbuf = vb2_ioctl_qbuf,
724 .vidioc_dqbuf = vb2_ioctl_dqbuf,
725 .vidioc_expbuf = vb2_ioctl_expbuf,
726 .vidioc_streamon = vb2_ioctl_streamon,
727 .vidioc_streamoff = vb2_ioctl_streamoff,
729 .vidioc_log_status = v4l2_ctrl_log_status,
730 .vidioc_subscribe_event = v4l2_ctrl_subscribe_event,
731 .vidioc_unsubscribe_event = v4l2_event_unsubscribe,
735 * The set of file operations. Note that all these ops are standard core
738 static const struct v4l2_file_operations skel_fops = {
739 .owner = THIS_MODULE,
740 .open = v4l2_fh_open,
741 .release = vb2_fop_release,
742 .unlocked_ioctl = video_ioctl2,
743 .read = vb2_fop_read,
744 .mmap = vb2_fop_mmap,
745 .poll = vb2_fop_poll,
749 * The initial setup of this device instance. Note that the initial state of
750 * the driver should be complete. So the initial format, standard, timings
751 * and video input should all be initialized to some reasonable value.
753 static int skeleton_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
755 /* The initial timings are chosen to be 720p60. */
756 static const struct v4l2_dv_timings timings_def =
757 V4L2_DV_BT_CEA_1280X720P60;
758 struct skeleton *skel;
759 struct video_device *vdev;
760 struct v4l2_ctrl_handler *hdl;
765 ret = pci_enable_device(pdev);
768 ret = pci_set_dma_mask(pdev, DMA_BIT_MASK(32));
770 dev_err(&pdev->dev, "no suitable DMA available.\n");
774 /* Allocate a new instance */
775 skel = devm_kzalloc(&pdev->dev, sizeof(struct skeleton), GFP_KERNEL);
781 /* Allocate the interrupt */
782 ret = devm_request_irq(&pdev->dev, pdev->irq,
783 skeleton_irq, 0, KBUILD_MODNAME, skel);
785 dev_err(&pdev->dev, "request_irq failed\n");
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);
795 /* Initialize the top-level structure */
796 ret = v4l2_device_register(&pdev->dev, &skel->v4l2_dev);
800 mutex_init(&skel->lock);
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);
817 skel->v4l2_dev.ctrl_handler = hdl;
819 /* Initialize the vb2 queue */
821 q->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
822 q->io_modes = VB2_MMAP | VB2_DMABUF | VB2_READ;
825 q->buf_struct_size = sizeof(struct skel_buffer);
827 q->mem_ops = &vb2_dma_contig_memops;
828 q->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
830 * Assume that this DMA engine needs to have at least two buffers
831 * available before it can be started. The start_streaming() op
832 * won't be called until at least this many buffers are queued up.
834 q->min_buffers_needed = 2;
836 * The serialization lock for the streaming ioctls. This is the same
837 * as the main serialization lock, but if some of the non-streaming
838 * ioctls could take a long time to execute, then you might want to
839 * have a different lock here to prevent VIDIOC_DQBUF from being
840 * blocked while waiting for another action to finish. This is
841 * generally not needed for PCI devices, but USB devices usually do
842 * want a separate lock here.
844 q->lock = &skel->lock;
846 * Since this driver can only do 32-bit DMA we must make sure that
847 * the vb2 core will allocate the buffers in 32-bit DMA memory.
849 q->gfp_flags = GFP_DMA32;
850 ret = vb2_queue_init(q);
854 INIT_LIST_HEAD(&skel->buf_list);
855 spin_lock_init(&skel->qlock);
857 /* Initialize the video_device structure */
859 strlcpy(vdev->name, KBUILD_MODNAME, sizeof(vdev->name));
861 * There is nothing to clean up, so release is set to an empty release
862 * function. The release callback must be non-NULL.
864 vdev->release = video_device_release_empty;
865 vdev->fops = &skel_fops,
866 vdev->ioctl_ops = &skel_ioctl_ops,
867 vdev->device_caps = V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_READWRITE |
870 * The main serialization lock. All ioctls are serialized by this
871 * lock. Exception: if q->lock is set, then the streaming ioctls
872 * are serialized by that separate lock.
874 vdev->lock = &skel->lock;
876 vdev->v4l2_dev = &skel->v4l2_dev;
877 /* Supported SDTV standards, if any */
878 vdev->tvnorms = SKEL_TVNORMS;
879 video_set_drvdata(vdev, skel);
881 ret = video_register_device(vdev, VFL_TYPE_GRABBER, -1);
885 dev_info(&pdev->dev, "V4L2 PCI Skeleton Driver loaded\n");
889 v4l2_ctrl_handler_free(&skel->ctrl_handler);
890 v4l2_device_unregister(&skel->v4l2_dev);
892 pci_disable_device(pdev);
896 static void skeleton_remove(struct pci_dev *pdev)
898 struct v4l2_device *v4l2_dev = pci_get_drvdata(pdev);
899 struct skeleton *skel = container_of(v4l2_dev, struct skeleton, v4l2_dev);
901 video_unregister_device(&skel->vdev);
902 v4l2_ctrl_handler_free(&skel->ctrl_handler);
903 v4l2_device_unregister(&skel->v4l2_dev);
904 pci_disable_device(skel->pdev);
907 static struct pci_driver skeleton_driver = {
908 .name = KBUILD_MODNAME,
909 .probe = skeleton_probe,
910 .remove = skeleton_remove,
911 .id_table = skeleton_pci_tbl,
914 module_pci_driver(skeleton_driver);