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  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * This is a V4L2 PCI Skeleton Driver. It gives an initial skeleton source
  4 * for use with other PCI drivers.
  5 *
  6 * This skeleton PCI driver assumes that the card has an S-Video connector as
  7 * input 0 and an HDMI connector as input 1.
  8 *
  9 * Copyright 2014 Cisco Systems, Inc. and/or its affiliates. All rights reserved.
 10 */
 11
 12#include <linux/types.h>
 13#include <linux/kernel.h>
 14#include <linux/module.h>
 15#include <linux/init.h>
 16#include <linux/kmod.h>
 17#include <linux/mutex.h>
 18#include <linux/pci.h>
 19#include <linux/interrupt.h>
 20#include <linux/videodev2.h>
 21#include <linux/v4l2-dv-timings.h>
 22#include <media/v4l2-device.h>
 23#include <media/v4l2-dev.h>
 24#include <media/v4l2-ioctl.h>
 25#include <media/v4l2-dv-timings.h>
 26#include <media/v4l2-ctrls.h>
 27#include <media/v4l2-event.h>
 28#include <media/videobuf2-v4l2.h>
 29#include <media/videobuf2-dma-contig.h>
 30
 31MODULE_DESCRIPTION("V4L2 PCI Skeleton Driver");
 32MODULE_AUTHOR("Hans Verkuil");
 33MODULE_LICENSE("GPL v2");
 34
 35/**
 36 * struct skeleton - All internal data for one instance of device
 37 * @pdev: PCI device
 38 * @v4l2_dev: top-level v4l2 device struct
 39 * @vdev: video node structure
 40 * @ctrl_handler: control handler structure
 41 * @lock: ioctl serialization mutex
 42 * @std: current SDTV standard
 43 * @timings: current HDTV timings
 44 * @format: current pix format
 45 * @input: current video input (0 = SDTV, 1 = HDTV)
 46 * @queue: vb2 video capture queue
 47 * @qlock: spinlock controlling access to buf_list and sequence
 48 * @buf_list: list of buffers queued for DMA
 49 * @field: the field (TOP/BOTTOM/other) of the current buffer
 50 * @sequence: frame sequence counter
 51 */
 52struct skeleton {
 53	struct pci_dev *pdev;
 54	struct v4l2_device v4l2_dev;
 55	struct video_device vdev;
 56	struct v4l2_ctrl_handler ctrl_handler;
 57	struct mutex lock;
 58	v4l2_std_id std;
 59	struct v4l2_dv_timings timings;
 60	struct v4l2_pix_format format;
 61	unsigned input;
 62
 63	struct vb2_queue queue;
 64
 65	spinlock_t qlock;
 66	struct list_head buf_list;
 67	unsigned field;
 68	unsigned sequence;
 69};
 70
 71struct skel_buffer {
 72	struct vb2_v4l2_buffer vb;
 73	struct list_head list;
 74};
 75
 76static inline struct skel_buffer *to_skel_buffer(struct vb2_v4l2_buffer *vbuf)
 77{
 78	return container_of(vbuf, struct skel_buffer, vb);
 79}
 80
 81static const struct pci_device_id skeleton_pci_tbl[] = {
 82	/* { PCI_DEVICE(PCI_VENDOR_ID_, PCI_DEVICE_ID_) }, */
 83	{ 0, }
 84};
 85MODULE_DEVICE_TABLE(pci, skeleton_pci_tbl);
 86
 87/*
 88 * HDTV: this structure has the capabilities of the HDTV receiver.
 89 * It is used to constrain the huge list of possible formats based
 90 * upon the hardware capabilities.
 91 */
 92static const struct v4l2_dv_timings_cap skel_timings_cap = {
 93	.type = V4L2_DV_BT_656_1120,
 94	/* keep this initialization for compatibility with GCC < 4.4.6 */
 95	.reserved = { 0 },
 96	V4L2_INIT_BT_TIMINGS(
 97		720, 1920,		/* min/max width */
 98		480, 1080,		/* min/max height */
 99		27000000, 74250000,	/* min/max pixelclock*/
100		V4L2_DV_BT_STD_CEA861,	/* Supported standards */
101		/* capabilities */
102		V4L2_DV_BT_CAP_INTERLACED | V4L2_DV_BT_CAP_PROGRESSIVE
103	)
104};
105
106/*
107 * Supported SDTV standards. This does the same job as skel_timings_cap, but
108 * for standard TV formats.
109 */
110#define SKEL_TVNORMS V4L2_STD_ALL
111
112/*
113 * Interrupt handler: typically interrupts happen after a new frame has been
114 * captured. It is the job of the handler to remove the new frame from the
115 * internal list and give it back to the vb2 framework, updating the sequence
116 * counter, field and timestamp at the same time.
117 */
118static irqreturn_t skeleton_irq(int irq, void *dev_id)
119{
120#ifdef TODO
121	struct skeleton *skel = dev_id;
122
123	/* handle interrupt */
124
125	/* Once a new frame has been captured, mark it as done like this: */
126	if (captured_new_frame) {
127		...
128		spin_lock(&skel->qlock);
129		list_del(&new_buf->list);
130		spin_unlock(&skel->qlock);
131		new_buf->vb.vb2_buf.timestamp = ktime_get_ns();
132		new_buf->vb.sequence = skel->sequence++;
133		new_buf->vb.field = skel->field;
134		if (skel->format.field == V4L2_FIELD_ALTERNATE) {
135			if (skel->field == V4L2_FIELD_BOTTOM)
136				skel->field = V4L2_FIELD_TOP;
137			else if (skel->field == V4L2_FIELD_TOP)
138				skel->field = V4L2_FIELD_BOTTOM;
139		}
140		vb2_buffer_done(&new_buf->vb.vb2_buf, VB2_BUF_STATE_DONE);
141	}
142#endif
143	return IRQ_HANDLED;
144}
145
146/*
147 * Setup the constraints of the queue: besides setting the number of planes
148 * per buffer and the size and allocation context of each plane, it also
149 * checks if sufficient buffers have been allocated. Usually 3 is a good
150 * minimum number: many DMA engines need a minimum of 2 buffers in the
151 * queue and you need to have another available for userspace processing.
152 */
153static int queue_setup(struct vb2_queue *vq,
154		       unsigned int *nbuffers, unsigned int *nplanes,
155		       unsigned int sizes[], struct device *alloc_devs[])
156{
157	struct skeleton *skel = vb2_get_drv_priv(vq);
158	unsigned int q_num_bufs = vb2_get_num_buffers(vq);
159
160	skel->field = skel->format.field;
161	if (skel->field == V4L2_FIELD_ALTERNATE) {
162		/*
163		 * You cannot use read() with FIELD_ALTERNATE since the field
164		 * information (TOP/BOTTOM) cannot be passed back to the user.
165		 */
166		if (vb2_fileio_is_active(vq))
167			return -EINVAL;
168		skel->field = V4L2_FIELD_TOP;
169	}
170
171	if (q_num_bufs + *nbuffers < 3)
172		*nbuffers = 3 - q_num_bufs;
173
174	if (*nplanes)
175		return sizes[0] < skel->format.sizeimage ? -EINVAL : 0;
176	*nplanes = 1;
177	sizes[0] = skel->format.sizeimage;
178	return 0;
179}
180
181/*
182 * Prepare the buffer for queueing to the DMA engine: check and set the
183 * payload size.
184 */
185static int buffer_prepare(struct vb2_buffer *vb)
186{
187	struct skeleton *skel = vb2_get_drv_priv(vb->vb2_queue);
188	unsigned long size = skel->format.sizeimage;
189
190	if (vb2_plane_size(vb, 0) < size) {
191		dev_err(&skel->pdev->dev, "buffer too small (%lu < %lu)\n",
192			 vb2_plane_size(vb, 0), size);
193		return -EINVAL;
194	}
195
196	vb2_set_plane_payload(vb, 0, size);
197	return 0;
198}
199
200/*
201 * Queue this buffer to the DMA engine.
202 */
203static void buffer_queue(struct vb2_buffer *vb)
204{
205	struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
206	struct skeleton *skel = vb2_get_drv_priv(vb->vb2_queue);
207	struct skel_buffer *buf = to_skel_buffer(vbuf);
208	unsigned long flags;
209
210	spin_lock_irqsave(&skel->qlock, flags);
211	list_add_tail(&buf->list, &skel->buf_list);
212
213	/* TODO: Update any DMA pointers if necessary */
214
215	spin_unlock_irqrestore(&skel->qlock, flags);
216}
217
218static void return_all_buffers(struct skeleton *skel,
219			       enum vb2_buffer_state state)
220{
221	struct skel_buffer *buf, *node;
222	unsigned long flags;
223
224	spin_lock_irqsave(&skel->qlock, flags);
225	list_for_each_entry_safe(buf, node, &skel->buf_list, list) {
226		vb2_buffer_done(&buf->vb.vb2_buf, state);
227		list_del(&buf->list);
228	}
229	spin_unlock_irqrestore(&skel->qlock, flags);
230}
231
232/*
233 * Start streaming. First check if the minimum number of buffers have been
234 * queued. If not, then return -ENOBUFS and the vb2 framework will call
235 * this function again the next time a buffer has been queued until enough
236 * buffers are available to actually start the DMA engine.
237 */
238static int start_streaming(struct vb2_queue *vq, unsigned int count)
239{
240	struct skeleton *skel = vb2_get_drv_priv(vq);
241	int ret = 0;
242
243	skel->sequence = 0;
244
245	/* TODO: start DMA */
246
247	if (ret) {
248		/*
249		 * In case of an error, return all active buffers to the
250		 * QUEUED state
251		 */
252		return_all_buffers(skel, VB2_BUF_STATE_QUEUED);
253	}
254	return ret;
255}
256
257/*
258 * Stop the DMA engine. Any remaining buffers in the DMA queue are dequeued
259 * and passed on to the vb2 framework marked as STATE_ERROR.
260 */
261static void stop_streaming(struct vb2_queue *vq)
262{
263	struct skeleton *skel = vb2_get_drv_priv(vq);
264
265	/* TODO: stop DMA */
266
267	/* Release all active buffers */
268	return_all_buffers(skel, VB2_BUF_STATE_ERROR);
269}
270
271/*
272 * The vb2 queue ops.
273 */
274static const struct vb2_ops skel_qops = {
275	.queue_setup		= queue_setup,
276	.buf_prepare		= buffer_prepare,
277	.buf_queue		= buffer_queue,
278	.start_streaming	= start_streaming,
279	.stop_streaming		= stop_streaming,
280};
281
282/*
283 * Required ioctl querycap. Note that the version field is prefilled with
284 * the version of the kernel.
285 */
286static int skeleton_querycap(struct file *file, void *priv,
287			     struct v4l2_capability *cap)
288{
289	struct skeleton *skel = video_drvdata(file);
290
291	strscpy(cap->driver, KBUILD_MODNAME, sizeof(cap->driver));
292	strscpy(cap->card, "V4L2 PCI Skeleton", sizeof(cap->card));
293	snprintf(cap->bus_info, sizeof(cap->bus_info), "PCI:%s",
294		 pci_name(skel->pdev));
295	return 0;
296}
297
298/*
299 * Helper function to check and correct struct v4l2_pix_format. It's used
300 * not only in VIDIOC_TRY/S_FMT, but also elsewhere if changes to the SDTV
301 * standard, HDTV timings or the video input would require updating the
302 * current format.
303 */
304static void skeleton_fill_pix_format(struct skeleton *skel,
305				     struct v4l2_pix_format *pix)
306{
307	pix->pixelformat = V4L2_PIX_FMT_YUYV;
308	if (skel->input == 0) {
309		/* S-Video input */
310		pix->width = 720;
311		pix->height = (skel->std & V4L2_STD_525_60) ? 480 : 576;
312		pix->field = V4L2_FIELD_INTERLACED;
313		pix->colorspace = V4L2_COLORSPACE_SMPTE170M;
314	} else {
315		/* HDMI input */
316		pix->width = skel->timings.bt.width;
317		pix->height = skel->timings.bt.height;
318		if (skel->timings.bt.interlaced) {
319			pix->field = V4L2_FIELD_ALTERNATE;
320			pix->height /= 2;
321		} else {
322			pix->field = V4L2_FIELD_NONE;
323		}
324		pix->colorspace = V4L2_COLORSPACE_REC709;
325	}
326
327	/*
328	 * The YUYV format is four bytes for every two pixels, so bytesperline
329	 * is width * 2.
330	 */
331	pix->bytesperline = pix->width * 2;
332	pix->sizeimage = pix->bytesperline * pix->height;
333	pix->priv = 0;
334}
335
336static int skeleton_try_fmt_vid_cap(struct file *file, void *priv,
337				    struct v4l2_format *f)
338{
339	struct skeleton *skel = video_drvdata(file);
340	struct v4l2_pix_format *pix = &f->fmt.pix;
341
342	/*
343	 * Due to historical reasons providing try_fmt with an unsupported
344	 * pixelformat will return -EINVAL for video receivers. Webcam drivers,
345	 * however, will silently correct the pixelformat. Some video capture
346	 * applications rely on this behavior...
347	 */
348	if (pix->pixelformat != V4L2_PIX_FMT_YUYV)
349		return -EINVAL;
350	skeleton_fill_pix_format(skel, pix);
351	return 0;
352}
353
354static int skeleton_s_fmt_vid_cap(struct file *file, void *priv,
355				  struct v4l2_format *f)
356{
357	struct skeleton *skel = video_drvdata(file);
358	int ret;
359
360	ret = skeleton_try_fmt_vid_cap(file, priv, f);
361	if (ret)
362		return ret;
363
364	/*
365	 * It is not allowed to change the format while buffers for use with
366	 * streaming have already been allocated.
367	 */
368	if (vb2_is_busy(&skel->queue))
369		return -EBUSY;
370
371	/* TODO: change format */
372	skel->format = f->fmt.pix;
373	return 0;
374}
375
376static int skeleton_g_fmt_vid_cap(struct file *file, void *priv,
377				  struct v4l2_format *f)
378{
379	struct skeleton *skel = video_drvdata(file);
380
381	f->fmt.pix = skel->format;
382	return 0;
383}
384
385static int skeleton_enum_fmt_vid_cap(struct file *file, void *priv,
386				     struct v4l2_fmtdesc *f)
387{
388	if (f->index != 0)
389		return -EINVAL;
390
391	f->pixelformat = V4L2_PIX_FMT_YUYV;
392	return 0;
393}
394
395static int skeleton_s_std(struct file *file, void *priv, v4l2_std_id std)
396{
397	struct skeleton *skel = video_drvdata(file);
398
399	/* S_STD is not supported on the HDMI input */
400	if (skel->input)
401		return -ENODATA;
402
403	/*
404	 * No change, so just return. Some applications call S_STD again after
405	 * the buffers for streaming have been set up, so we have to allow for
406	 * this behavior.
407	 */
408	if (std == skel->std)
409		return 0;
410
411	/*
412	 * Changing the standard implies a format change, which is not allowed
413	 * while buffers for use with streaming have already been allocated.
414	 */
415	if (vb2_is_busy(&skel->queue))
416		return -EBUSY;
417
418	/* TODO: handle changing std */
419
420	skel->std = std;
421
422	/* Update the internal format */
423	skeleton_fill_pix_format(skel, &skel->format);
424	return 0;
425}
426
427static int skeleton_g_std(struct file *file, void *priv, v4l2_std_id *std)
428{
429	struct skeleton *skel = video_drvdata(file);
430
431	/* G_STD is not supported on the HDMI input */
432	if (skel->input)
433		return -ENODATA;
434
435	*std = skel->std;
436	return 0;
437}
438
439/*
440 * Query the current standard as seen by the hardware. This function shall
441 * never actually change the standard, it just detects and reports.
442 * The framework will initially set *std to tvnorms (i.e. the set of
443 * supported standards by this input), and this function should just AND
444 * this value. If there is no signal, then *std should be set to 0.
445 */
446static int skeleton_querystd(struct file *file, void *priv, v4l2_std_id *std)
447{
448	struct skeleton *skel = video_drvdata(file);
449
450	/* QUERY_STD is not supported on the HDMI input */
451	if (skel->input)
452		return -ENODATA;
453
454#ifdef TODO
455	/*
456	 * Query currently seen standard. Initial value of *std is
457	 * V4L2_STD_ALL. This function should look something like this:
458	 */
459	get_signal_info();
460	if (no_signal) {
461		*std = 0;
462		return 0;
463	}
464	/* Use signal information to reduce the number of possible standards */
465	if (signal_has_525_lines)
466		*std &= V4L2_STD_525_60;
467	else
468		*std &= V4L2_STD_625_50;
469#endif
470	return 0;
471}
472
473static int skeleton_s_dv_timings(struct file *file, void *_fh,
474				 struct v4l2_dv_timings *timings)
475{
476	struct skeleton *skel = video_drvdata(file);
477
478	/* S_DV_TIMINGS is not supported on the S-Video input */
479	if (skel->input == 0)
480		return -ENODATA;
481
482	/* Quick sanity check */
483	if (!v4l2_valid_dv_timings(timings, &skel_timings_cap, NULL, NULL))
484		return -EINVAL;
485
486	/* Check if the timings are part of the CEA-861 timings. */
487	if (!v4l2_find_dv_timings_cap(timings, &skel_timings_cap,
488				      0, NULL, NULL))
489		return -EINVAL;
490
491	/* Return 0 if the new timings are the same as the current timings. */
492	if (v4l2_match_dv_timings(timings, &skel->timings, 0, false))
493		return 0;
494
495	/*
496	 * Changing the timings implies a format change, which is not allowed
497	 * while buffers for use with streaming have already been allocated.
498	 */
499	if (vb2_is_busy(&skel->queue))
500		return -EBUSY;
501
502	/* TODO: Configure new timings */
503
504	/* Save timings */
505	skel->timings = *timings;
506
507	/* Update the internal format */
508	skeleton_fill_pix_format(skel, &skel->format);
509	return 0;
510}
511
512static int skeleton_g_dv_timings(struct file *file, void *_fh,
513				 struct v4l2_dv_timings *timings)
514{
515	struct skeleton *skel = video_drvdata(file);
516
517	/* G_DV_TIMINGS is not supported on the S-Video input */
518	if (skel->input == 0)
519		return -ENODATA;
520
521	*timings = skel->timings;
522	return 0;
523}
524
525static int skeleton_enum_dv_timings(struct file *file, void *_fh,
526				    struct v4l2_enum_dv_timings *timings)
527{
528	struct skeleton *skel = video_drvdata(file);
529
530	/* ENUM_DV_TIMINGS is not supported on the S-Video input */
531	if (skel->input == 0)
532		return -ENODATA;
533
534	return v4l2_enum_dv_timings_cap(timings, &skel_timings_cap,
535					NULL, NULL);
536}
537
538/*
539 * Query the current timings as seen by the hardware. This function shall
540 * never actually change the timings, it just detects and reports.
541 * If no signal is detected, then return -ENOLINK. If the hardware cannot
542 * lock to the signal, then return -ENOLCK. If the signal is out of range
543 * of the capabilities of the system (e.g., it is possible that the receiver
544 * can lock but that the DMA engine it is connected to cannot handle
545 * pixelclocks above a certain frequency), then -ERANGE is returned.
546 */
547static int skeleton_query_dv_timings(struct file *file, void *_fh,
548				     struct v4l2_dv_timings *timings)
549{
550	struct skeleton *skel = video_drvdata(file);
551
552	/* QUERY_DV_TIMINGS is not supported on the S-Video input */
553	if (skel->input == 0)
554		return -ENODATA;
555
556#ifdef TODO
557	/*
558	 * Query currently seen timings. This function should look
559	 * something like this:
560	 */
561	detect_timings();
562	if (no_signal)
563		return -ENOLINK;
564	if (cannot_lock_to_signal)
565		return -ENOLCK;
566	if (signal_out_of_range_of_capabilities)
567		return -ERANGE;
568
569	/* Useful for debugging */
570	v4l2_print_dv_timings(skel->v4l2_dev.name, "query_dv_timings:",
571			timings, true);
572#endif
573	return 0;
574}
575
576static int skeleton_dv_timings_cap(struct file *file, void *fh,
577				   struct v4l2_dv_timings_cap *cap)
578{
579	struct skeleton *skel = video_drvdata(file);
580
581	/* DV_TIMINGS_CAP is not supported on the S-Video input */
582	if (skel->input == 0)
583		return -ENODATA;
584	*cap = skel_timings_cap;
585	return 0;
586}
587
588static int skeleton_enum_input(struct file *file, void *priv,
589			       struct v4l2_input *i)
590{
591	if (i->index > 1)
592		return -EINVAL;
593
594	i->type = V4L2_INPUT_TYPE_CAMERA;
595	if (i->index == 0) {
596		i->std = SKEL_TVNORMS;
597		strscpy(i->name, "S-Video", sizeof(i->name));
598		i->capabilities = V4L2_IN_CAP_STD;
599	} else {
600		i->std = 0;
601		strscpy(i->name, "HDMI", sizeof(i->name));
602		i->capabilities = V4L2_IN_CAP_DV_TIMINGS;
603	}
604	return 0;
605}
606
607static int skeleton_s_input(struct file *file, void *priv, unsigned int i)
608{
609	struct skeleton *skel = video_drvdata(file);
610
611	if (i > 1)
612		return -EINVAL;
613
614	/*
615	 * Changing the input implies a format change, which is not allowed
616	 * while buffers for use with streaming have already been allocated.
617	 */
618	if (vb2_is_busy(&skel->queue))
619		return -EBUSY;
620
621	skel->input = i;
622	/*
623	 * Update tvnorms. The tvnorms value is used by the core to implement
624	 * VIDIOC_ENUMSTD so it has to be correct. If tvnorms == 0, then
625	 * ENUMSTD will return -ENODATA.
626	 */
627	skel->vdev.tvnorms = i ? 0 : SKEL_TVNORMS;
628
629	/* Update the internal format */
630	skeleton_fill_pix_format(skel, &skel->format);
631	return 0;
632}
633
634static int skeleton_g_input(struct file *file, void *priv, unsigned int *i)
635{
636	struct skeleton *skel = video_drvdata(file);
637
638	*i = skel->input;
639	return 0;
640}
641
642/* The control handler. */
643static int skeleton_s_ctrl(struct v4l2_ctrl *ctrl)
644{
645	/*struct skeleton *skel =
646		container_of(ctrl->handler, struct skeleton, ctrl_handler);*/
647
648	switch (ctrl->id) {
649	case V4L2_CID_BRIGHTNESS:
650		/* TODO: set brightness to ctrl->val */
651		break;
652	case V4L2_CID_CONTRAST:
653		/* TODO: set contrast to ctrl->val */
654		break;
655	case V4L2_CID_SATURATION:
656		/* TODO: set saturation to ctrl->val */
657		break;
658	case V4L2_CID_HUE:
659		/* TODO: set hue to ctrl->val */
660		break;
661	default:
662		return -EINVAL;
663	}
664	return 0;
665}
666
667/* ------------------------------------------------------------------
668	File operations for the device
669   ------------------------------------------------------------------*/
670
671static const struct v4l2_ctrl_ops skel_ctrl_ops = {
672	.s_ctrl = skeleton_s_ctrl,
673};
674
675/*
676 * The set of all supported ioctls. Note that all the streaming ioctls
677 * use the vb2 helper functions that take care of all the locking and
678 * that also do ownership tracking (i.e. only the filehandle that requested
679 * the buffers can call the streaming ioctls, all other filehandles will
680 * receive -EBUSY if they attempt to call the same streaming ioctls).
681 *
682 * The last three ioctls also use standard helper functions: these implement
683 * standard behavior for drivers with controls.
684 */
685static const struct v4l2_ioctl_ops skel_ioctl_ops = {
686	.vidioc_querycap = skeleton_querycap,
687	.vidioc_try_fmt_vid_cap = skeleton_try_fmt_vid_cap,
688	.vidioc_s_fmt_vid_cap = skeleton_s_fmt_vid_cap,
689	.vidioc_g_fmt_vid_cap = skeleton_g_fmt_vid_cap,
690	.vidioc_enum_fmt_vid_cap = skeleton_enum_fmt_vid_cap,
691
692	.vidioc_g_std = skeleton_g_std,
693	.vidioc_s_std = skeleton_s_std,
694	.vidioc_querystd = skeleton_querystd,
695
696	.vidioc_s_dv_timings = skeleton_s_dv_timings,
697	.vidioc_g_dv_timings = skeleton_g_dv_timings,
698	.vidioc_enum_dv_timings = skeleton_enum_dv_timings,
699	.vidioc_query_dv_timings = skeleton_query_dv_timings,
700	.vidioc_dv_timings_cap = skeleton_dv_timings_cap,
701
702	.vidioc_enum_input = skeleton_enum_input,
703	.vidioc_g_input = skeleton_g_input,
704	.vidioc_s_input = skeleton_s_input,
705
706	.vidioc_reqbufs = vb2_ioctl_reqbufs,
707	.vidioc_create_bufs = vb2_ioctl_create_bufs,
708	.vidioc_querybuf = vb2_ioctl_querybuf,
709	.vidioc_qbuf = vb2_ioctl_qbuf,
710	.vidioc_dqbuf = vb2_ioctl_dqbuf,
711	.vidioc_expbuf = vb2_ioctl_expbuf,
712	.vidioc_streamon = vb2_ioctl_streamon,
713	.vidioc_streamoff = vb2_ioctl_streamoff,
714
715	.vidioc_log_status = v4l2_ctrl_log_status,
716	.vidioc_subscribe_event = v4l2_ctrl_subscribe_event,
717	.vidioc_unsubscribe_event = v4l2_event_unsubscribe,
718};
719
720/*
721 * The set of file operations. Note that all these ops are standard core
722 * helper functions.
723 */
724static const struct v4l2_file_operations skel_fops = {
725	.owner = THIS_MODULE,
726	.open = v4l2_fh_open,
727	.release = vb2_fop_release,
728	.unlocked_ioctl = video_ioctl2,
729	.read = vb2_fop_read,
730	.mmap = vb2_fop_mmap,
731	.poll = vb2_fop_poll,
732};
733
734/*
735 * The initial setup of this device instance. Note that the initial state of
736 * the driver should be complete. So the initial format, standard, timings
737 * and video input should all be initialized to some reasonable value.
738 */
739static int skeleton_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
740{
741	/* The initial timings are chosen to be 720p60. */
742	static const struct v4l2_dv_timings timings_def =
743		V4L2_DV_BT_CEA_1280X720P60;
744	struct skeleton *skel;
745	struct video_device *vdev;
746	struct v4l2_ctrl_handler *hdl;
747	struct vb2_queue *q;
748	int ret;
749
750	/* Enable PCI */
751	ret = pci_enable_device(pdev);
752	if (ret)
753		return ret;
754	ret = dma_set_mask(&pdev->dev, DMA_BIT_MASK(32));
755	if (ret) {
756		dev_err(&pdev->dev, "no suitable DMA available.\n");
757		goto disable_pci;
758	}
759
760	/* Allocate a new instance */
761	skel = devm_kzalloc(&pdev->dev, sizeof(struct skeleton), GFP_KERNEL);
762	if (!skel) {
763		ret = -ENOMEM;
764		goto disable_pci;
765	}
766
767	/* Allocate the interrupt */
768	ret = devm_request_irq(&pdev->dev, pdev->irq,
769			       skeleton_irq, 0, KBUILD_MODNAME, skel);
770	if (ret) {
771		dev_err(&pdev->dev, "request_irq failed\n");
772		goto disable_pci;
773	}
774	skel->pdev = pdev;
775
776	/* Fill in the initial format-related settings */
777	skel->timings = timings_def;
778	skel->std = V4L2_STD_625_50;
779	skeleton_fill_pix_format(skel, &skel->format);
780
781	/* Initialize the top-level structure */
782	ret = v4l2_device_register(&pdev->dev, &skel->v4l2_dev);
783	if (ret)
784		goto disable_pci;
785
786	mutex_init(&skel->lock);
787
788	/* Add the controls */
789	hdl = &skel->ctrl_handler;
790	v4l2_ctrl_handler_init(hdl, 4);
791	v4l2_ctrl_new_std(hdl, &skel_ctrl_ops,
792			  V4L2_CID_BRIGHTNESS, 0, 255, 1, 127);
793	v4l2_ctrl_new_std(hdl, &skel_ctrl_ops,
794			  V4L2_CID_CONTRAST, 0, 255, 1, 16);
795	v4l2_ctrl_new_std(hdl, &skel_ctrl_ops,
796			  V4L2_CID_SATURATION, 0, 255, 1, 127);
797	v4l2_ctrl_new_std(hdl, &skel_ctrl_ops,
798			  V4L2_CID_HUE, -128, 127, 1, 0);
799	if (hdl->error) {
800		ret = hdl->error;
801		goto free_hdl;
802	}
803	skel->v4l2_dev.ctrl_handler = hdl;
804
805	/* Initialize the vb2 queue */
806	q = &skel->queue;
807	q->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
808	q->io_modes = VB2_MMAP | VB2_DMABUF | VB2_READ;
809	q->dev = &pdev->dev;
810	q->drv_priv = skel;
811	q->buf_struct_size = sizeof(struct skel_buffer);
812	q->ops = &skel_qops;
813	q->mem_ops = &vb2_dma_contig_memops;
814	q->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
815	/*
816	 * Assume that this DMA engine needs to have at least two buffers
817	 * available before it can be started. The start_streaming() op
818	 * won't be called until at least this many buffers are queued up.
819	 */
820	q->min_queued_buffers = 2;
821	/*
822	 * The serialization lock for the streaming ioctls. This is the same
823	 * as the main serialization lock, but if some of the non-streaming
824	 * ioctls could take a long time to execute, then you might want to
825	 * have a different lock here to prevent VIDIOC_DQBUF from being
826	 * blocked while waiting for another action to finish. This is
827	 * generally not needed for PCI devices, but USB devices usually do
828	 * want a separate lock here.
829	 */
830	q->lock = &skel->lock;
831	/*
832	 * Since this driver can only do 32-bit DMA we must make sure that
833	 * the vb2 core will allocate the buffers in 32-bit DMA memory.
834	 */
835	q->gfp_flags = GFP_DMA32;
836	ret = vb2_queue_init(q);
837	if (ret)
838		goto free_hdl;
839
840	INIT_LIST_HEAD(&skel->buf_list);
841	spin_lock_init(&skel->qlock);
842
843	/* Initialize the video_device structure */
844	vdev = &skel->vdev;
845	strscpy(vdev->name, KBUILD_MODNAME, sizeof(vdev->name));
846	/*
847	 * There is nothing to clean up, so release is set to an empty release
848	 * function. The release callback must be non-NULL.
849	 */
850	vdev->release = video_device_release_empty;
851	vdev->fops = &skel_fops,
852	vdev->ioctl_ops = &skel_ioctl_ops,
853	vdev->device_caps = V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_READWRITE |
854			    V4L2_CAP_STREAMING;
855	/*
856	 * The main serialization lock. All ioctls are serialized by this
857	 * lock. Exception: if q->lock is set, then the streaming ioctls
858	 * are serialized by that separate lock.
859	 */
860	vdev->lock = &skel->lock;
861	vdev->queue = q;
862	vdev->v4l2_dev = &skel->v4l2_dev;
863	/* Supported SDTV standards, if any */
864	vdev->tvnorms = SKEL_TVNORMS;
865	video_set_drvdata(vdev, skel);
866
867	ret = video_register_device(vdev, VFL_TYPE_VIDEO, -1);
868	if (ret)
869		goto free_hdl;
870
871	dev_info(&pdev->dev, "V4L2 PCI Skeleton Driver loaded\n");
872	return 0;
873
874free_hdl:
875	v4l2_ctrl_handler_free(&skel->ctrl_handler);
876	v4l2_device_unregister(&skel->v4l2_dev);
877disable_pci:
878	pci_disable_device(pdev);
879	return ret;
880}
881
882static void skeleton_remove(struct pci_dev *pdev)
883{
884	struct v4l2_device *v4l2_dev = pci_get_drvdata(pdev);
885	struct skeleton *skel = container_of(v4l2_dev, struct skeleton, v4l2_dev);
886
887	video_unregister_device(&skel->vdev);
888	v4l2_ctrl_handler_free(&skel->ctrl_handler);
889	v4l2_device_unregister(&skel->v4l2_dev);
890	pci_disable_device(skel->pdev);
891}
892
893static struct pci_driver skeleton_driver = {
894	.name = KBUILD_MODNAME,
895	.probe = skeleton_probe,
896	.remove = skeleton_remove,
897	.id_table = skeleton_pci_tbl,
898};
899
900module_pci_driver(skeleton_driver);