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