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