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Based on kernel version 4.6.2. Page generated on 2016-06-08 13:09 EST.

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