1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Xilinx Video DMA
4  *
5  * Copyright (C) 2013-2015 Ideas on Board
6  * Copyright (C) 2013-2015 Xilinx, Inc.
7  *
8  * Contacts: Hyun Kwon <hyun.kwon@xilinx.com>
9  *           Laurent Pinchart <laurent.pinchart@ideasonboard.com>
10  */
11 
12 #include <linux/dma/xilinx_dma.h>
13 #include <linux/lcm.h>
14 #include <linux/list.h>
15 #include <linux/module.h>
16 #include <linux/of.h>
17 #include <linux/slab.h>
18 
19 #include <media/v4l2-dev.h>
20 #include <media/v4l2-fh.h>
21 #include <media/v4l2-ioctl.h>
22 #include <media/videobuf2-v4l2.h>
23 #include <media/videobuf2-dma-contig.h>
24 
25 #include "xilinx-dma.h"
26 #include "xilinx-vip.h"
27 #include "xilinx-vipp.h"
28 
29 #define XVIP_DMA_DEF_FORMAT		V4L2_PIX_FMT_YUYV
30 #define XVIP_DMA_DEF_WIDTH		1920
31 #define XVIP_DMA_DEF_HEIGHT		1080
32 
33 /* Minimum and maximum widths are expressed in bytes */
34 #define XVIP_DMA_MIN_WIDTH		1U
35 #define XVIP_DMA_MAX_WIDTH		65535U
36 #define XVIP_DMA_MIN_HEIGHT		1U
37 #define XVIP_DMA_MAX_HEIGHT		8191U
38 
39 /* -----------------------------------------------------------------------------
40  * Helper functions
41  */
42 
43 static struct v4l2_subdev *
44 xvip_dma_remote_subdev(struct media_pad *local, u32 *pad)
45 {
46 	struct media_pad *remote;
47 
48 	remote = media_entity_remote_pad(local);
49 	if (!remote || !is_media_entity_v4l2_subdev(remote->entity))
50 		return NULL;
51 
52 	if (pad)
53 		*pad = remote->index;
54 
55 	return media_entity_to_v4l2_subdev(remote->entity);
56 }
57 
58 static int xvip_dma_verify_format(struct xvip_dma *dma)
59 {
60 	struct v4l2_subdev_format fmt;
61 	struct v4l2_subdev *subdev;
62 	int ret;
63 
64 	subdev = xvip_dma_remote_subdev(&dma->pad, &fmt.pad);
65 	if (subdev == NULL)
66 		return -EPIPE;
67 
68 	fmt.which = V4L2_SUBDEV_FORMAT_ACTIVE;
69 	ret = v4l2_subdev_call(subdev, pad, get_fmt, NULL, &fmt);
70 	if (ret < 0)
71 		return ret == -ENOIOCTLCMD ? -EINVAL : ret;
72 
73 	if (dma->fmtinfo->code != fmt.format.code ||
74 	    dma->format.height != fmt.format.height ||
75 	    dma->format.width != fmt.format.width ||
76 	    dma->format.colorspace != fmt.format.colorspace)
77 		return -EINVAL;
78 
79 	return 0;
80 }
81 
82 /* -----------------------------------------------------------------------------
83  * Pipeline Stream Management
84  */
85 
86 /**
87  * xvip_pipeline_start_stop - Start ot stop streaming on a pipeline
88  * @pipe: The pipeline
89  * @start: Start (when true) or stop (when false) the pipeline
90  *
91  * Walk the entities chain starting at the pipeline output video node and start
92  * or stop all of them.
93  *
94  * Return: 0 if successful, or the return value of the failed video::s_stream
95  * operation otherwise.
96  */
97 static int xvip_pipeline_start_stop(struct xvip_pipeline *pipe, bool start)
98 {
99 	struct xvip_dma *dma = pipe->output;
100 	struct media_entity *entity;
101 	struct media_pad *pad;
102 	struct v4l2_subdev *subdev;
103 	int ret;
104 
105 	entity = &dma->video.entity;
106 	while (1) {
107 		pad = &entity->pads[0];
108 		if (!(pad->flags & MEDIA_PAD_FL_SINK))
109 			break;
110 
111 		pad = media_entity_remote_pad(pad);
112 		if (!pad || !is_media_entity_v4l2_subdev(pad->entity))
113 			break;
114 
115 		entity = pad->entity;
116 		subdev = media_entity_to_v4l2_subdev(entity);
117 
118 		ret = v4l2_subdev_call(subdev, video, s_stream, start);
119 		if (start && ret < 0 && ret != -ENOIOCTLCMD)
120 			return ret;
121 	}
122 
123 	return 0;
124 }
125 
126 /**
127  * xvip_pipeline_set_stream - Enable/disable streaming on a pipeline
128  * @pipe: The pipeline
129  * @on: Turn the stream on when true or off when false
130  *
131  * The pipeline is shared between all DMA engines connect at its input and
132  * output. While the stream state of DMA engines can be controlled
133  * independently, pipelines have a shared stream state that enable or disable
134  * all entities in the pipeline. For this reason the pipeline uses a streaming
135  * counter that tracks the number of DMA engines that have requested the stream
136  * to be enabled.
137  *
138  * When called with the @on argument set to true, this function will increment
139  * the pipeline streaming count. If the streaming count reaches the number of
140  * DMA engines in the pipeline it will enable all entities that belong to the
141  * pipeline.
142  *
143  * Similarly, when called with the @on argument set to false, this function will
144  * decrement the pipeline streaming count and disable all entities in the
145  * pipeline when the streaming count reaches zero.
146  *
147  * Return: 0 if successful, or the return value of the failed video::s_stream
148  * operation otherwise. Stopping the pipeline never fails. The pipeline state is
149  * not updated when the operation fails.
150  */
151 static int xvip_pipeline_set_stream(struct xvip_pipeline *pipe, bool on)
152 {
153 	int ret = 0;
154 
155 	mutex_lock(&pipe->lock);
156 
157 	if (on) {
158 		if (pipe->stream_count == pipe->num_dmas - 1) {
159 			ret = xvip_pipeline_start_stop(pipe, true);
160 			if (ret < 0)
161 				goto done;
162 		}
163 		pipe->stream_count++;
164 	} else {
165 		if (--pipe->stream_count == 0)
166 			xvip_pipeline_start_stop(pipe, false);
167 	}
168 
169 done:
170 	mutex_unlock(&pipe->lock);
171 	return ret;
172 }
173 
174 static int xvip_pipeline_validate(struct xvip_pipeline *pipe,
175 				  struct xvip_dma *start)
176 {
177 	struct media_graph graph;
178 	struct media_entity *entity = &start->video.entity;
179 	struct media_device *mdev = entity->graph_obj.mdev;
180 	unsigned int num_inputs = 0;
181 	unsigned int num_outputs = 0;
182 	int ret;
183 
184 	mutex_lock(&mdev->graph_mutex);
185 
186 	/* Walk the graph to locate the video nodes. */
187 	ret = media_graph_walk_init(&graph, mdev);
188 	if (ret) {
189 		mutex_unlock(&mdev->graph_mutex);
190 		return ret;
191 	}
192 
193 	media_graph_walk_start(&graph, entity);
194 
195 	while ((entity = media_graph_walk_next(&graph))) {
196 		struct xvip_dma *dma;
197 
198 		if (entity->function != MEDIA_ENT_F_IO_V4L)
199 			continue;
200 
201 		dma = to_xvip_dma(media_entity_to_video_device(entity));
202 
203 		if (dma->pad.flags & MEDIA_PAD_FL_SINK) {
204 			pipe->output = dma;
205 			num_outputs++;
206 		} else {
207 			num_inputs++;
208 		}
209 	}
210 
211 	mutex_unlock(&mdev->graph_mutex);
212 
213 	media_graph_walk_cleanup(&graph);
214 
215 	/* We need exactly one output and zero or one input. */
216 	if (num_outputs != 1 || num_inputs > 1)
217 		return -EPIPE;
218 
219 	pipe->num_dmas = num_inputs + num_outputs;
220 
221 	return 0;
222 }
223 
224 static void __xvip_pipeline_cleanup(struct xvip_pipeline *pipe)
225 {
226 	pipe->num_dmas = 0;
227 	pipe->output = NULL;
228 }
229 
230 /**
231  * xvip_pipeline_cleanup - Cleanup the pipeline after streaming
232  * @pipe: the pipeline
233  *
234  * Decrease the pipeline use count and clean it up if we were the last user.
235  */
236 static void xvip_pipeline_cleanup(struct xvip_pipeline *pipe)
237 {
238 	mutex_lock(&pipe->lock);
239 
240 	/* If we're the last user clean up the pipeline. */
241 	if (--pipe->use_count == 0)
242 		__xvip_pipeline_cleanup(pipe);
243 
244 	mutex_unlock(&pipe->lock);
245 }
246 
247 /**
248  * xvip_pipeline_prepare - Prepare the pipeline for streaming
249  * @pipe: the pipeline
250  * @dma: DMA engine at one end of the pipeline
251  *
252  * Validate the pipeline if no user exists yet, otherwise just increase the use
253  * count.
254  *
255  * Return: 0 if successful or -EPIPE if the pipeline is not valid.
256  */
257 static int xvip_pipeline_prepare(struct xvip_pipeline *pipe,
258 				 struct xvip_dma *dma)
259 {
260 	int ret;
261 
262 	mutex_lock(&pipe->lock);
263 
264 	/* If we're the first user validate and initialize the pipeline. */
265 	if (pipe->use_count == 0) {
266 		ret = xvip_pipeline_validate(pipe, dma);
267 		if (ret < 0) {
268 			__xvip_pipeline_cleanup(pipe);
269 			goto done;
270 		}
271 	}
272 
273 	pipe->use_count++;
274 	ret = 0;
275 
276 done:
277 	mutex_unlock(&pipe->lock);
278 	return ret;
279 }
280 
281 /* -----------------------------------------------------------------------------
282  * videobuf2 queue operations
283  */
284 
285 /**
286  * struct xvip_dma_buffer - Video DMA buffer
287  * @buf: vb2 buffer base object
288  * @queue: buffer list entry in the DMA engine queued buffers list
289  * @dma: DMA channel that uses the buffer
290  */
291 struct xvip_dma_buffer {
292 	struct vb2_v4l2_buffer buf;
293 	struct list_head queue;
294 	struct xvip_dma *dma;
295 };
296 
297 #define to_xvip_dma_buffer(vb)	container_of(vb, struct xvip_dma_buffer, buf)
298 
299 static void xvip_dma_complete(void *param)
300 {
301 	struct xvip_dma_buffer *buf = param;
302 	struct xvip_dma *dma = buf->dma;
303 
304 	spin_lock(&dma->queued_lock);
305 	list_del(&buf->queue);
306 	spin_unlock(&dma->queued_lock);
307 
308 	buf->buf.field = V4L2_FIELD_NONE;
309 	buf->buf.sequence = dma->sequence++;
310 	buf->buf.vb2_buf.timestamp = ktime_get_ns();
311 	vb2_set_plane_payload(&buf->buf.vb2_buf, 0, dma->format.sizeimage);
312 	vb2_buffer_done(&buf->buf.vb2_buf, VB2_BUF_STATE_DONE);
313 }
314 
315 static int
316 xvip_dma_queue_setup(struct vb2_queue *vq,
317 		     unsigned int *nbuffers, unsigned int *nplanes,
318 		     unsigned int sizes[], struct device *alloc_devs[])
319 {
320 	struct xvip_dma *dma = vb2_get_drv_priv(vq);
321 
322 	/* Make sure the image size is large enough. */
323 	if (*nplanes)
324 		return sizes[0] < dma->format.sizeimage ? -EINVAL : 0;
325 
326 	*nplanes = 1;
327 	sizes[0] = dma->format.sizeimage;
328 
329 	return 0;
330 }
331 
332 static int xvip_dma_buffer_prepare(struct vb2_buffer *vb)
333 {
334 	struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
335 	struct xvip_dma *dma = vb2_get_drv_priv(vb->vb2_queue);
336 	struct xvip_dma_buffer *buf = to_xvip_dma_buffer(vbuf);
337 
338 	buf->dma = dma;
339 
340 	return 0;
341 }
342 
343 static void xvip_dma_buffer_queue(struct vb2_buffer *vb)
344 {
345 	struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
346 	struct xvip_dma *dma = vb2_get_drv_priv(vb->vb2_queue);
347 	struct xvip_dma_buffer *buf = to_xvip_dma_buffer(vbuf);
348 	struct dma_async_tx_descriptor *desc;
349 	dma_addr_t addr = vb2_dma_contig_plane_dma_addr(vb, 0);
350 	u32 flags;
351 
352 	if (dma->queue.type == V4L2_BUF_TYPE_VIDEO_CAPTURE) {
353 		flags = DMA_PREP_INTERRUPT | DMA_CTRL_ACK;
354 		dma->xt.dir = DMA_DEV_TO_MEM;
355 		dma->xt.src_sgl = false;
356 		dma->xt.dst_sgl = true;
357 		dma->xt.dst_start = addr;
358 	} else {
359 		flags = DMA_PREP_INTERRUPT | DMA_CTRL_ACK;
360 		dma->xt.dir = DMA_MEM_TO_DEV;
361 		dma->xt.src_sgl = true;
362 		dma->xt.dst_sgl = false;
363 		dma->xt.src_start = addr;
364 	}
365 
366 	dma->xt.frame_size = 1;
367 	dma->sgl[0].size = dma->format.width * dma->fmtinfo->bpp;
368 	dma->sgl[0].icg = dma->format.bytesperline - dma->sgl[0].size;
369 	dma->xt.numf = dma->format.height;
370 
371 	desc = dmaengine_prep_interleaved_dma(dma->dma, &dma->xt, flags);
372 	if (!desc) {
373 		dev_err(dma->xdev->dev, "Failed to prepare DMA transfer\n");
374 		vb2_buffer_done(&buf->buf.vb2_buf, VB2_BUF_STATE_ERROR);
375 		return;
376 	}
377 	desc->callback = xvip_dma_complete;
378 	desc->callback_param = buf;
379 
380 	spin_lock_irq(&dma->queued_lock);
381 	list_add_tail(&buf->queue, &dma->queued_bufs);
382 	spin_unlock_irq(&dma->queued_lock);
383 
384 	dmaengine_submit(desc);
385 
386 	if (vb2_is_streaming(&dma->queue))
387 		dma_async_issue_pending(dma->dma);
388 }
389 
390 static int xvip_dma_start_streaming(struct vb2_queue *vq, unsigned int count)
391 {
392 	struct xvip_dma *dma = vb2_get_drv_priv(vq);
393 	struct xvip_dma_buffer *buf, *nbuf;
394 	struct xvip_pipeline *pipe;
395 	int ret;
396 
397 	dma->sequence = 0;
398 
399 	/*
400 	 * Start streaming on the pipeline. No link touching an entity in the
401 	 * pipeline can be activated or deactivated once streaming is started.
402 	 *
403 	 * Use the pipeline object embedded in the first DMA object that starts
404 	 * streaming.
405 	 */
406 	pipe = dma->video.entity.pipe
407 	     ? to_xvip_pipeline(&dma->video.entity) : &dma->pipe;
408 
409 	ret = media_pipeline_start(&dma->video.entity, &pipe->pipe);
410 	if (ret < 0)
411 		goto error;
412 
413 	/* Verify that the configured format matches the output of the
414 	 * connected subdev.
415 	 */
416 	ret = xvip_dma_verify_format(dma);
417 	if (ret < 0)
418 		goto error_stop;
419 
420 	ret = xvip_pipeline_prepare(pipe, dma);
421 	if (ret < 0)
422 		goto error_stop;
423 
424 	/* Start the DMA engine. This must be done before starting the blocks
425 	 * in the pipeline to avoid DMA synchronization issues.
426 	 */
427 	dma_async_issue_pending(dma->dma);
428 
429 	/* Start the pipeline. */
430 	xvip_pipeline_set_stream(pipe, true);
431 
432 	return 0;
433 
434 error_stop:
435 	media_pipeline_stop(&dma->video.entity);
436 
437 error:
438 	/* Give back all queued buffers to videobuf2. */
439 	spin_lock_irq(&dma->queued_lock);
440 	list_for_each_entry_safe(buf, nbuf, &dma->queued_bufs, queue) {
441 		vb2_buffer_done(&buf->buf.vb2_buf, VB2_BUF_STATE_QUEUED);
442 		list_del(&buf->queue);
443 	}
444 	spin_unlock_irq(&dma->queued_lock);
445 
446 	return ret;
447 }
448 
449 static void xvip_dma_stop_streaming(struct vb2_queue *vq)
450 {
451 	struct xvip_dma *dma = vb2_get_drv_priv(vq);
452 	struct xvip_pipeline *pipe = to_xvip_pipeline(&dma->video.entity);
453 	struct xvip_dma_buffer *buf, *nbuf;
454 
455 	/* Stop the pipeline. */
456 	xvip_pipeline_set_stream(pipe, false);
457 
458 	/* Stop and reset the DMA engine. */
459 	dmaengine_terminate_all(dma->dma);
460 
461 	/* Cleanup the pipeline and mark it as being stopped. */
462 	xvip_pipeline_cleanup(pipe);
463 	media_pipeline_stop(&dma->video.entity);
464 
465 	/* Give back all queued buffers to videobuf2. */
466 	spin_lock_irq(&dma->queued_lock);
467 	list_for_each_entry_safe(buf, nbuf, &dma->queued_bufs, queue) {
468 		vb2_buffer_done(&buf->buf.vb2_buf, VB2_BUF_STATE_ERROR);
469 		list_del(&buf->queue);
470 	}
471 	spin_unlock_irq(&dma->queued_lock);
472 }
473 
474 static const struct vb2_ops xvip_dma_queue_qops = {
475 	.queue_setup = xvip_dma_queue_setup,
476 	.buf_prepare = xvip_dma_buffer_prepare,
477 	.buf_queue = xvip_dma_buffer_queue,
478 	.wait_prepare = vb2_ops_wait_prepare,
479 	.wait_finish = vb2_ops_wait_finish,
480 	.start_streaming = xvip_dma_start_streaming,
481 	.stop_streaming = xvip_dma_stop_streaming,
482 };
483 
484 /* -----------------------------------------------------------------------------
485  * V4L2 ioctls
486  */
487 
488 static int
489 xvip_dma_querycap(struct file *file, void *fh, struct v4l2_capability *cap)
490 {
491 	struct v4l2_fh *vfh = file->private_data;
492 	struct xvip_dma *dma = to_xvip_dma(vfh->vdev);
493 
494 	cap->device_caps = V4L2_CAP_STREAMING;
495 
496 	if (dma->queue.type == V4L2_BUF_TYPE_VIDEO_CAPTURE)
497 		cap->device_caps |= V4L2_CAP_VIDEO_CAPTURE;
498 	else
499 		cap->device_caps |= V4L2_CAP_VIDEO_OUTPUT;
500 
501 	cap->capabilities = cap->device_caps | V4L2_CAP_DEVICE_CAPS
502 			  | dma->xdev->v4l2_caps;
503 
504 	strscpy(cap->driver, "xilinx-vipp", sizeof(cap->driver));
505 	strscpy(cap->card, dma->video.name, sizeof(cap->card));
506 	snprintf(cap->bus_info, sizeof(cap->bus_info), "platform:%pOFn:%u",
507 		 dma->xdev->dev->of_node, dma->port);
508 
509 	return 0;
510 }
511 
512 /* FIXME: without this callback function, some applications are not configured
513  * with correct formats, and it results in frames in wrong format. Whether this
514  * callback needs to be required is not clearly defined, so it should be
515  * clarified through the mailing list.
516  */
517 static int
518 xvip_dma_enum_format(struct file *file, void *fh, struct v4l2_fmtdesc *f)
519 {
520 	struct v4l2_fh *vfh = file->private_data;
521 	struct xvip_dma *dma = to_xvip_dma(vfh->vdev);
522 
523 	if (f->index > 0)
524 		return -EINVAL;
525 
526 	f->pixelformat = dma->format.pixelformat;
527 	strscpy(f->description, dma->fmtinfo->description,
528 		sizeof(f->description));
529 
530 	return 0;
531 }
532 
533 static int
534 xvip_dma_get_format(struct file *file, void *fh, struct v4l2_format *format)
535 {
536 	struct v4l2_fh *vfh = file->private_data;
537 	struct xvip_dma *dma = to_xvip_dma(vfh->vdev);
538 
539 	format->fmt.pix = dma->format;
540 
541 	return 0;
542 }
543 
544 static void
545 __xvip_dma_try_format(struct xvip_dma *dma, struct v4l2_pix_format *pix,
546 		      const struct xvip_video_format **fmtinfo)
547 {
548 	const struct xvip_video_format *info;
549 	unsigned int min_width;
550 	unsigned int max_width;
551 	unsigned int min_bpl;
552 	unsigned int max_bpl;
553 	unsigned int width;
554 	unsigned int align;
555 	unsigned int bpl;
556 
557 	/* Retrieve format information and select the default format if the
558 	 * requested format isn't supported.
559 	 */
560 	info = xvip_get_format_by_fourcc(pix->pixelformat);
561 	if (IS_ERR(info))
562 		info = xvip_get_format_by_fourcc(XVIP_DMA_DEF_FORMAT);
563 
564 	pix->pixelformat = info->fourcc;
565 	pix->field = V4L2_FIELD_NONE;
566 
567 	/* The transfer alignment requirements are expressed in bytes. Compute
568 	 * the minimum and maximum values, clamp the requested width and convert
569 	 * it back to pixels.
570 	 */
571 	align = lcm(dma->align, info->bpp);
572 	min_width = roundup(XVIP_DMA_MIN_WIDTH, align);
573 	max_width = rounddown(XVIP_DMA_MAX_WIDTH, align);
574 	width = rounddown(pix->width * info->bpp, align);
575 
576 	pix->width = clamp(width, min_width, max_width) / info->bpp;
577 	pix->height = clamp(pix->height, XVIP_DMA_MIN_HEIGHT,
578 			    XVIP_DMA_MAX_HEIGHT);
579 
580 	/* Clamp the requested bytes per line value. If the maximum bytes per
581 	 * line value is zero, the module doesn't support user configurable line
582 	 * sizes. Override the requested value with the minimum in that case.
583 	 */
584 	min_bpl = pix->width * info->bpp;
585 	max_bpl = rounddown(XVIP_DMA_MAX_WIDTH, dma->align);
586 	bpl = rounddown(pix->bytesperline, dma->align);
587 
588 	pix->bytesperline = clamp(bpl, min_bpl, max_bpl);
589 	pix->sizeimage = pix->bytesperline * pix->height;
590 
591 	if (fmtinfo)
592 		*fmtinfo = info;
593 }
594 
595 static int
596 xvip_dma_try_format(struct file *file, void *fh, struct v4l2_format *format)
597 {
598 	struct v4l2_fh *vfh = file->private_data;
599 	struct xvip_dma *dma = to_xvip_dma(vfh->vdev);
600 
601 	__xvip_dma_try_format(dma, &format->fmt.pix, NULL);
602 	return 0;
603 }
604 
605 static int
606 xvip_dma_set_format(struct file *file, void *fh, struct v4l2_format *format)
607 {
608 	struct v4l2_fh *vfh = file->private_data;
609 	struct xvip_dma *dma = to_xvip_dma(vfh->vdev);
610 	const struct xvip_video_format *info;
611 
612 	__xvip_dma_try_format(dma, &format->fmt.pix, &info);
613 
614 	if (vb2_is_busy(&dma->queue))
615 		return -EBUSY;
616 
617 	dma->format = format->fmt.pix;
618 	dma->fmtinfo = info;
619 
620 	return 0;
621 }
622 
623 static const struct v4l2_ioctl_ops xvip_dma_ioctl_ops = {
624 	.vidioc_querycap		= xvip_dma_querycap,
625 	.vidioc_enum_fmt_vid_cap	= xvip_dma_enum_format,
626 	.vidioc_g_fmt_vid_cap		= xvip_dma_get_format,
627 	.vidioc_g_fmt_vid_out		= xvip_dma_get_format,
628 	.vidioc_s_fmt_vid_cap		= xvip_dma_set_format,
629 	.vidioc_s_fmt_vid_out		= xvip_dma_set_format,
630 	.vidioc_try_fmt_vid_cap		= xvip_dma_try_format,
631 	.vidioc_try_fmt_vid_out		= xvip_dma_try_format,
632 	.vidioc_reqbufs			= vb2_ioctl_reqbufs,
633 	.vidioc_querybuf		= vb2_ioctl_querybuf,
634 	.vidioc_qbuf			= vb2_ioctl_qbuf,
635 	.vidioc_dqbuf			= vb2_ioctl_dqbuf,
636 	.vidioc_create_bufs		= vb2_ioctl_create_bufs,
637 	.vidioc_expbuf			= vb2_ioctl_expbuf,
638 	.vidioc_streamon		= vb2_ioctl_streamon,
639 	.vidioc_streamoff		= vb2_ioctl_streamoff,
640 };
641 
642 /* -----------------------------------------------------------------------------
643  * V4L2 file operations
644  */
645 
646 static const struct v4l2_file_operations xvip_dma_fops = {
647 	.owner		= THIS_MODULE,
648 	.unlocked_ioctl	= video_ioctl2,
649 	.open		= v4l2_fh_open,
650 	.release	= vb2_fop_release,
651 	.poll		= vb2_fop_poll,
652 	.mmap		= vb2_fop_mmap,
653 };
654 
655 /* -----------------------------------------------------------------------------
656  * Xilinx Video DMA Core
657  */
658 
659 int xvip_dma_init(struct xvip_composite_device *xdev, struct xvip_dma *dma,
660 		  enum v4l2_buf_type type, unsigned int port)
661 {
662 	char name[16];
663 	int ret;
664 
665 	dma->xdev = xdev;
666 	dma->port = port;
667 	mutex_init(&dma->lock);
668 	mutex_init(&dma->pipe.lock);
669 	INIT_LIST_HEAD(&dma->queued_bufs);
670 	spin_lock_init(&dma->queued_lock);
671 
672 	dma->fmtinfo = xvip_get_format_by_fourcc(XVIP_DMA_DEF_FORMAT);
673 	dma->format.pixelformat = dma->fmtinfo->fourcc;
674 	dma->format.colorspace = V4L2_COLORSPACE_SRGB;
675 	dma->format.field = V4L2_FIELD_NONE;
676 	dma->format.width = XVIP_DMA_DEF_WIDTH;
677 	dma->format.height = XVIP_DMA_DEF_HEIGHT;
678 	dma->format.bytesperline = dma->format.width * dma->fmtinfo->bpp;
679 	dma->format.sizeimage = dma->format.bytesperline * dma->format.height;
680 
681 	/* Initialize the media entity... */
682 	dma->pad.flags = type == V4L2_BUF_TYPE_VIDEO_CAPTURE
683 		       ? MEDIA_PAD_FL_SINK : MEDIA_PAD_FL_SOURCE;
684 
685 	ret = media_entity_pads_init(&dma->video.entity, 1, &dma->pad);
686 	if (ret < 0)
687 		goto error;
688 
689 	/* ... and the video node... */
690 	dma->video.fops = &xvip_dma_fops;
691 	dma->video.v4l2_dev = &xdev->v4l2_dev;
692 	dma->video.queue = &dma->queue;
693 	snprintf(dma->video.name, sizeof(dma->video.name), "%pOFn %s %u",
694 		 xdev->dev->of_node,
695 		 type == V4L2_BUF_TYPE_VIDEO_CAPTURE ? "output" : "input",
696 		 port);
697 	dma->video.vfl_type = VFL_TYPE_GRABBER;
698 	dma->video.vfl_dir = type == V4L2_BUF_TYPE_VIDEO_CAPTURE
699 			   ? VFL_DIR_RX : VFL_DIR_TX;
700 	dma->video.release = video_device_release_empty;
701 	dma->video.ioctl_ops = &xvip_dma_ioctl_ops;
702 	dma->video.lock = &dma->lock;
703 
704 	video_set_drvdata(&dma->video, dma);
705 
706 	/* ... and the buffers queue... */
707 	/* Don't enable VB2_READ and VB2_WRITE, as using the read() and write()
708 	 * V4L2 APIs would be inefficient. Testing on the command line with a
709 	 * 'cat /dev/video?' thus won't be possible, but given that the driver
710 	 * anyway requires a test tool to setup the pipeline before any video
711 	 * stream can be started, requiring a specific V4L2 test tool as well
712 	 * instead of 'cat' isn't really a drawback.
713 	 */
714 	dma->queue.type = type;
715 	dma->queue.io_modes = VB2_MMAP | VB2_USERPTR | VB2_DMABUF;
716 	dma->queue.lock = &dma->lock;
717 	dma->queue.drv_priv = dma;
718 	dma->queue.buf_struct_size = sizeof(struct xvip_dma_buffer);
719 	dma->queue.ops = &xvip_dma_queue_qops;
720 	dma->queue.mem_ops = &vb2_dma_contig_memops;
721 	dma->queue.timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC
722 				   | V4L2_BUF_FLAG_TSTAMP_SRC_EOF;
723 	dma->queue.dev = dma->xdev->dev;
724 	ret = vb2_queue_init(&dma->queue);
725 	if (ret < 0) {
726 		dev_err(dma->xdev->dev, "failed to initialize VB2 queue\n");
727 		goto error;
728 	}
729 
730 	/* ... and the DMA channel. */
731 	snprintf(name, sizeof(name), "port%u", port);
732 	dma->dma = dma_request_slave_channel(dma->xdev->dev, name);
733 	if (dma->dma == NULL) {
734 		dev_err(dma->xdev->dev, "no VDMA channel found\n");
735 		ret = -ENODEV;
736 		goto error;
737 	}
738 
739 	dma->align = 1 << dma->dma->device->copy_align;
740 
741 	ret = video_register_device(&dma->video, VFL_TYPE_GRABBER, -1);
742 	if (ret < 0) {
743 		dev_err(dma->xdev->dev, "failed to register video device\n");
744 		goto error;
745 	}
746 
747 	return 0;
748 
749 error:
750 	xvip_dma_cleanup(dma);
751 	return ret;
752 }
753 
754 void xvip_dma_cleanup(struct xvip_dma *dma)
755 {
756 	if (video_is_registered(&dma->video))
757 		video_unregister_device(&dma->video);
758 
759 	if (dma->dma)
760 		dma_release_channel(dma->dma);
761 
762 	media_entity_cleanup(&dma->video.entity);
763 
764 	mutex_destroy(&dma->lock);
765 	mutex_destroy(&dma->pipe.lock);
766 }
767