1 /*
2  * Xilinx Video IP Composite Device
3  *
4  * Copyright (C) 2013-2015 Ideas on Board
5  * Copyright (C) 2013-2015 Xilinx, Inc.
6  *
7  * Contacts: Hyun Kwon <hyun.kwon@xilinx.com>
8  *           Laurent Pinchart <laurent.pinchart@ideasonboard.com>
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License version 2 as
12  * published by the Free Software Foundation.
13  */
14 
15 #include <linux/list.h>
16 #include <linux/module.h>
17 #include <linux/of.h>
18 #include <linux/of_graph.h>
19 #include <linux/platform_device.h>
20 #include <linux/slab.h>
21 
22 #include <media/v4l2-async.h>
23 #include <media/v4l2-common.h>
24 #include <media/v4l2-device.h>
25 #include <media/v4l2-fwnode.h>
26 
27 #include "xilinx-dma.h"
28 #include "xilinx-vipp.h"
29 
30 #define XVIPP_DMA_S2MM				0
31 #define XVIPP_DMA_MM2S				1
32 
33 /**
34  * struct xvip_graph_entity - Entity in the video graph
35  * @list: list entry in a graph entities list
36  * @node: the entity's DT node
37  * @entity: media entity, from the corresponding V4L2 subdev
38  * @asd: subdev asynchronous registration information
39  * @subdev: V4L2 subdev
40  */
41 struct xvip_graph_entity {
42 	struct list_head list;
43 	struct device_node *node;
44 	struct media_entity *entity;
45 
46 	struct v4l2_async_subdev asd;
47 	struct v4l2_subdev *subdev;
48 };
49 
50 /* -----------------------------------------------------------------------------
51  * Graph Management
52  */
53 
54 static struct xvip_graph_entity *
55 xvip_graph_find_entity(struct xvip_composite_device *xdev,
56 		       const struct device_node *node)
57 {
58 	struct xvip_graph_entity *entity;
59 
60 	list_for_each_entry(entity, &xdev->entities, list) {
61 		if (entity->node == node)
62 			return entity;
63 	}
64 
65 	return NULL;
66 }
67 
68 static int xvip_graph_build_one(struct xvip_composite_device *xdev,
69 				struct xvip_graph_entity *entity)
70 {
71 	u32 link_flags = MEDIA_LNK_FL_ENABLED;
72 	struct media_entity *local = entity->entity;
73 	struct media_entity *remote;
74 	struct media_pad *local_pad;
75 	struct media_pad *remote_pad;
76 	struct xvip_graph_entity *ent;
77 	struct v4l2_fwnode_link link;
78 	struct device_node *ep = NULL;
79 	int ret = 0;
80 
81 	dev_dbg(xdev->dev, "creating links for entity %s\n", local->name);
82 
83 	while (1) {
84 		/* Get the next endpoint and parse its link. */
85 		ep = of_graph_get_next_endpoint(entity->node, ep);
86 		if (ep == NULL)
87 			break;
88 
89 		dev_dbg(xdev->dev, "processing endpoint %pOF\n", ep);
90 
91 		ret = v4l2_fwnode_parse_link(of_fwnode_handle(ep), &link);
92 		if (ret < 0) {
93 			dev_err(xdev->dev, "failed to parse link for %pOF\n",
94 				ep);
95 			continue;
96 		}
97 
98 		/* Skip sink ports, they will be processed from the other end of
99 		 * the link.
100 		 */
101 		if (link.local_port >= local->num_pads) {
102 			dev_err(xdev->dev, "invalid port number %u for %pOF\n",
103 				link.local_port,
104 				to_of_node(link.local_node));
105 			v4l2_fwnode_put_link(&link);
106 			ret = -EINVAL;
107 			break;
108 		}
109 
110 		local_pad = &local->pads[link.local_port];
111 
112 		if (local_pad->flags & MEDIA_PAD_FL_SINK) {
113 			dev_dbg(xdev->dev, "skipping sink port %pOF:%u\n",
114 				to_of_node(link.local_node),
115 				link.local_port);
116 			v4l2_fwnode_put_link(&link);
117 			continue;
118 		}
119 
120 		/* Skip DMA engines, they will be processed separately. */
121 		if (link.remote_node == of_fwnode_handle(xdev->dev->of_node)) {
122 			dev_dbg(xdev->dev, "skipping DMA port %pOF:%u\n",
123 				to_of_node(link.local_node),
124 				link.local_port);
125 			v4l2_fwnode_put_link(&link);
126 			continue;
127 		}
128 
129 		/* Find the remote entity. */
130 		ent = xvip_graph_find_entity(xdev,
131 					     to_of_node(link.remote_node));
132 		if (ent == NULL) {
133 			dev_err(xdev->dev, "no entity found for %pOF\n",
134 				to_of_node(link.remote_node));
135 			v4l2_fwnode_put_link(&link);
136 			ret = -ENODEV;
137 			break;
138 		}
139 
140 		remote = ent->entity;
141 
142 		if (link.remote_port >= remote->num_pads) {
143 			dev_err(xdev->dev, "invalid port number %u on %pOF\n",
144 				link.remote_port, to_of_node(link.remote_node));
145 			v4l2_fwnode_put_link(&link);
146 			ret = -EINVAL;
147 			break;
148 		}
149 
150 		remote_pad = &remote->pads[link.remote_port];
151 
152 		v4l2_fwnode_put_link(&link);
153 
154 		/* Create the media link. */
155 		dev_dbg(xdev->dev, "creating %s:%u -> %s:%u link\n",
156 			local->name, local_pad->index,
157 			remote->name, remote_pad->index);
158 
159 		ret = media_create_pad_link(local, local_pad->index,
160 					       remote, remote_pad->index,
161 					       link_flags);
162 		if (ret < 0) {
163 			dev_err(xdev->dev,
164 				"failed to create %s:%u -> %s:%u link\n",
165 				local->name, local_pad->index,
166 				remote->name, remote_pad->index);
167 			break;
168 		}
169 	}
170 
171 	of_node_put(ep);
172 	return ret;
173 }
174 
175 static struct xvip_dma *
176 xvip_graph_find_dma(struct xvip_composite_device *xdev, unsigned int port)
177 {
178 	struct xvip_dma *dma;
179 
180 	list_for_each_entry(dma, &xdev->dmas, list) {
181 		if (dma->port == port)
182 			return dma;
183 	}
184 
185 	return NULL;
186 }
187 
188 static int xvip_graph_build_dma(struct xvip_composite_device *xdev)
189 {
190 	u32 link_flags = MEDIA_LNK_FL_ENABLED;
191 	struct device_node *node = xdev->dev->of_node;
192 	struct media_entity *source;
193 	struct media_entity *sink;
194 	struct media_pad *source_pad;
195 	struct media_pad *sink_pad;
196 	struct xvip_graph_entity *ent;
197 	struct v4l2_fwnode_link link;
198 	struct device_node *ep = NULL;
199 	struct xvip_dma *dma;
200 	int ret = 0;
201 
202 	dev_dbg(xdev->dev, "creating links for DMA engines\n");
203 
204 	while (1) {
205 		/* Get the next endpoint and parse its link. */
206 		ep = of_graph_get_next_endpoint(node, ep);
207 		if (ep == NULL)
208 			break;
209 
210 		dev_dbg(xdev->dev, "processing endpoint %pOF\n", ep);
211 
212 		ret = v4l2_fwnode_parse_link(of_fwnode_handle(ep), &link);
213 		if (ret < 0) {
214 			dev_err(xdev->dev, "failed to parse link for %pOF\n",
215 				ep);
216 			continue;
217 		}
218 
219 		/* Find the DMA engine. */
220 		dma = xvip_graph_find_dma(xdev, link.local_port);
221 		if (dma == NULL) {
222 			dev_err(xdev->dev, "no DMA engine found for port %u\n",
223 				link.local_port);
224 			v4l2_fwnode_put_link(&link);
225 			ret = -EINVAL;
226 			break;
227 		}
228 
229 		dev_dbg(xdev->dev, "creating link for DMA engine %s\n",
230 			dma->video.name);
231 
232 		/* Find the remote entity. */
233 		ent = xvip_graph_find_entity(xdev,
234 					     to_of_node(link.remote_node));
235 		if (ent == NULL) {
236 			dev_err(xdev->dev, "no entity found for %pOF\n",
237 				to_of_node(link.remote_node));
238 			v4l2_fwnode_put_link(&link);
239 			ret = -ENODEV;
240 			break;
241 		}
242 
243 		if (link.remote_port >= ent->entity->num_pads) {
244 			dev_err(xdev->dev, "invalid port number %u on %pOF\n",
245 				link.remote_port,
246 				to_of_node(link.remote_node));
247 			v4l2_fwnode_put_link(&link);
248 			ret = -EINVAL;
249 			break;
250 		}
251 
252 		if (dma->pad.flags & MEDIA_PAD_FL_SOURCE) {
253 			source = &dma->video.entity;
254 			source_pad = &dma->pad;
255 			sink = ent->entity;
256 			sink_pad = &sink->pads[link.remote_port];
257 		} else {
258 			source = ent->entity;
259 			source_pad = &source->pads[link.remote_port];
260 			sink = &dma->video.entity;
261 			sink_pad = &dma->pad;
262 		}
263 
264 		v4l2_fwnode_put_link(&link);
265 
266 		/* Create the media link. */
267 		dev_dbg(xdev->dev, "creating %s:%u -> %s:%u link\n",
268 			source->name, source_pad->index,
269 			sink->name, sink_pad->index);
270 
271 		ret = media_create_pad_link(source, source_pad->index,
272 					       sink, sink_pad->index,
273 					       link_flags);
274 		if (ret < 0) {
275 			dev_err(xdev->dev,
276 				"failed to create %s:%u -> %s:%u link\n",
277 				source->name, source_pad->index,
278 				sink->name, sink_pad->index);
279 			break;
280 		}
281 	}
282 
283 	of_node_put(ep);
284 	return ret;
285 }
286 
287 static int xvip_graph_notify_complete(struct v4l2_async_notifier *notifier)
288 {
289 	struct xvip_composite_device *xdev =
290 		container_of(notifier, struct xvip_composite_device, notifier);
291 	struct xvip_graph_entity *entity;
292 	int ret;
293 
294 	dev_dbg(xdev->dev, "notify complete, all subdevs registered\n");
295 
296 	/* Create links for every entity. */
297 	list_for_each_entry(entity, &xdev->entities, list) {
298 		ret = xvip_graph_build_one(xdev, entity);
299 		if (ret < 0)
300 			return ret;
301 	}
302 
303 	/* Create links for DMA channels. */
304 	ret = xvip_graph_build_dma(xdev);
305 	if (ret < 0)
306 		return ret;
307 
308 	ret = v4l2_device_register_subdev_nodes(&xdev->v4l2_dev);
309 	if (ret < 0)
310 		dev_err(xdev->dev, "failed to register subdev nodes\n");
311 
312 	return media_device_register(&xdev->media_dev);
313 }
314 
315 static int xvip_graph_notify_bound(struct v4l2_async_notifier *notifier,
316 				   struct v4l2_subdev *subdev,
317 				   struct v4l2_async_subdev *asd)
318 {
319 	struct xvip_composite_device *xdev =
320 		container_of(notifier, struct xvip_composite_device, notifier);
321 	struct xvip_graph_entity *entity;
322 
323 	/* Locate the entity corresponding to the bound subdev and store the
324 	 * subdev pointer.
325 	 */
326 	list_for_each_entry(entity, &xdev->entities, list) {
327 		if (entity->node != subdev->dev->of_node)
328 			continue;
329 
330 		if (entity->subdev) {
331 			dev_err(xdev->dev, "duplicate subdev for node %pOF\n",
332 				entity->node);
333 			return -EINVAL;
334 		}
335 
336 		dev_dbg(xdev->dev, "subdev %s bound\n", subdev->name);
337 		entity->entity = &subdev->entity;
338 		entity->subdev = subdev;
339 		return 0;
340 	}
341 
342 	dev_err(xdev->dev, "no entity for subdev %s\n", subdev->name);
343 	return -EINVAL;
344 }
345 
346 static const struct v4l2_async_notifier_operations xvip_graph_notify_ops = {
347 	.bound = xvip_graph_notify_bound,
348 	.complete = xvip_graph_notify_complete,
349 };
350 
351 static int xvip_graph_parse_one(struct xvip_composite_device *xdev,
352 				struct device_node *node)
353 {
354 	struct xvip_graph_entity *entity;
355 	struct device_node *remote;
356 	struct device_node *ep = NULL;
357 	int ret = 0;
358 
359 	dev_dbg(xdev->dev, "parsing node %pOF\n", node);
360 
361 	while (1) {
362 		ep = of_graph_get_next_endpoint(node, ep);
363 		if (ep == NULL)
364 			break;
365 
366 		dev_dbg(xdev->dev, "handling endpoint %pOF\n", ep);
367 
368 		remote = of_graph_get_remote_port_parent(ep);
369 		if (remote == NULL) {
370 			ret = -EINVAL;
371 			break;
372 		}
373 
374 		/* Skip entities that we have already processed. */
375 		if (remote == xdev->dev->of_node ||
376 		    xvip_graph_find_entity(xdev, remote)) {
377 			of_node_put(remote);
378 			continue;
379 		}
380 
381 		entity = devm_kzalloc(xdev->dev, sizeof(*entity), GFP_KERNEL);
382 		if (entity == NULL) {
383 			of_node_put(remote);
384 			ret = -ENOMEM;
385 			break;
386 		}
387 
388 		entity->node = remote;
389 		entity->asd.match_type = V4L2_ASYNC_MATCH_FWNODE;
390 		entity->asd.match.fwnode = of_fwnode_handle(remote);
391 		list_add_tail(&entity->list, &xdev->entities);
392 		xdev->num_subdevs++;
393 	}
394 
395 	of_node_put(ep);
396 	return ret;
397 }
398 
399 static int xvip_graph_parse(struct xvip_composite_device *xdev)
400 {
401 	struct xvip_graph_entity *entity;
402 	int ret;
403 
404 	/*
405 	 * Walk the links to parse the full graph. Start by parsing the
406 	 * composite node and then parse entities in turn. The list_for_each
407 	 * loop will handle entities added at the end of the list while walking
408 	 * the links.
409 	 */
410 	ret = xvip_graph_parse_one(xdev, xdev->dev->of_node);
411 	if (ret < 0)
412 		return 0;
413 
414 	list_for_each_entry(entity, &xdev->entities, list) {
415 		ret = xvip_graph_parse_one(xdev, entity->node);
416 		if (ret < 0)
417 			break;
418 	}
419 
420 	return ret;
421 }
422 
423 static int xvip_graph_dma_init_one(struct xvip_composite_device *xdev,
424 				   struct device_node *node)
425 {
426 	struct xvip_dma *dma;
427 	enum v4l2_buf_type type;
428 	const char *direction;
429 	unsigned int index;
430 	int ret;
431 
432 	ret = of_property_read_string(node, "direction", &direction);
433 	if (ret < 0)
434 		return ret;
435 
436 	if (strcmp(direction, "input") == 0)
437 		type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
438 	else if (strcmp(direction, "output") == 0)
439 		type = V4L2_BUF_TYPE_VIDEO_OUTPUT;
440 	else
441 		return -EINVAL;
442 
443 	of_property_read_u32(node, "reg", &index);
444 
445 	dma = devm_kzalloc(xdev->dev, sizeof(*dma), GFP_KERNEL);
446 	if (dma == NULL)
447 		return -ENOMEM;
448 
449 	ret = xvip_dma_init(xdev, dma, type, index);
450 	if (ret < 0) {
451 		dev_err(xdev->dev, "%pOF initialization failed\n", node);
452 		return ret;
453 	}
454 
455 	list_add_tail(&dma->list, &xdev->dmas);
456 
457 	xdev->v4l2_caps |= type == V4L2_BUF_TYPE_VIDEO_CAPTURE
458 			 ? V4L2_CAP_VIDEO_CAPTURE : V4L2_CAP_VIDEO_OUTPUT;
459 
460 	return 0;
461 }
462 
463 static int xvip_graph_dma_init(struct xvip_composite_device *xdev)
464 {
465 	struct device_node *ports;
466 	struct device_node *port;
467 	int ret;
468 
469 	ports = of_get_child_by_name(xdev->dev->of_node, "ports");
470 	if (ports == NULL) {
471 		dev_err(xdev->dev, "ports node not present\n");
472 		return -EINVAL;
473 	}
474 
475 	for_each_child_of_node(ports, port) {
476 		ret = xvip_graph_dma_init_one(xdev, port);
477 		if (ret < 0) {
478 			of_node_put(port);
479 			return ret;
480 		}
481 	}
482 
483 	return 0;
484 }
485 
486 static void xvip_graph_cleanup(struct xvip_composite_device *xdev)
487 {
488 	struct xvip_graph_entity *entityp;
489 	struct xvip_graph_entity *entity;
490 	struct xvip_dma *dmap;
491 	struct xvip_dma *dma;
492 
493 	v4l2_async_notifier_unregister(&xdev->notifier);
494 
495 	list_for_each_entry_safe(entity, entityp, &xdev->entities, list) {
496 		of_node_put(entity->node);
497 		list_del(&entity->list);
498 	}
499 
500 	list_for_each_entry_safe(dma, dmap, &xdev->dmas, list) {
501 		xvip_dma_cleanup(dma);
502 		list_del(&dma->list);
503 	}
504 }
505 
506 static int xvip_graph_init(struct xvip_composite_device *xdev)
507 {
508 	struct xvip_graph_entity *entity;
509 	struct v4l2_async_subdev **subdevs = NULL;
510 	unsigned int num_subdevs;
511 	unsigned int i;
512 	int ret;
513 
514 	/* Init the DMA channels. */
515 	ret = xvip_graph_dma_init(xdev);
516 	if (ret < 0) {
517 		dev_err(xdev->dev, "DMA initialization failed\n");
518 		goto done;
519 	}
520 
521 	/* Parse the graph to extract a list of subdevice DT nodes. */
522 	ret = xvip_graph_parse(xdev);
523 	if (ret < 0) {
524 		dev_err(xdev->dev, "graph parsing failed\n");
525 		goto done;
526 	}
527 
528 	if (!xdev->num_subdevs) {
529 		dev_err(xdev->dev, "no subdev found in graph\n");
530 		goto done;
531 	}
532 
533 	/* Register the subdevices notifier. */
534 	num_subdevs = xdev->num_subdevs;
535 	subdevs = devm_kzalloc(xdev->dev, sizeof(*subdevs) * num_subdevs,
536 			       GFP_KERNEL);
537 	if (subdevs == NULL) {
538 		ret = -ENOMEM;
539 		goto done;
540 	}
541 
542 	i = 0;
543 	list_for_each_entry(entity, &xdev->entities, list)
544 		subdevs[i++] = &entity->asd;
545 
546 	xdev->notifier.subdevs = subdevs;
547 	xdev->notifier.num_subdevs = num_subdevs;
548 	xdev->notifier.ops = &xvip_graph_notify_ops;
549 
550 	ret = v4l2_async_notifier_register(&xdev->v4l2_dev, &xdev->notifier);
551 	if (ret < 0) {
552 		dev_err(xdev->dev, "notifier registration failed\n");
553 		goto done;
554 	}
555 
556 	ret = 0;
557 
558 done:
559 	if (ret < 0)
560 		xvip_graph_cleanup(xdev);
561 
562 	return ret;
563 }
564 
565 /* -----------------------------------------------------------------------------
566  * Media Controller and V4L2
567  */
568 
569 static void xvip_composite_v4l2_cleanup(struct xvip_composite_device *xdev)
570 {
571 	v4l2_device_unregister(&xdev->v4l2_dev);
572 	media_device_unregister(&xdev->media_dev);
573 	media_device_cleanup(&xdev->media_dev);
574 }
575 
576 static int xvip_composite_v4l2_init(struct xvip_composite_device *xdev)
577 {
578 	int ret;
579 
580 	xdev->media_dev.dev = xdev->dev;
581 	strlcpy(xdev->media_dev.model, "Xilinx Video Composite Device",
582 		sizeof(xdev->media_dev.model));
583 	xdev->media_dev.hw_revision = 0;
584 
585 	media_device_init(&xdev->media_dev);
586 
587 	xdev->v4l2_dev.mdev = &xdev->media_dev;
588 	ret = v4l2_device_register(xdev->dev, &xdev->v4l2_dev);
589 	if (ret < 0) {
590 		dev_err(xdev->dev, "V4L2 device registration failed (%d)\n",
591 			ret);
592 		media_device_cleanup(&xdev->media_dev);
593 		return ret;
594 	}
595 
596 	return 0;
597 }
598 
599 /* -----------------------------------------------------------------------------
600  * Platform Device Driver
601  */
602 
603 static int xvip_composite_probe(struct platform_device *pdev)
604 {
605 	struct xvip_composite_device *xdev;
606 	int ret;
607 
608 	xdev = devm_kzalloc(&pdev->dev, sizeof(*xdev), GFP_KERNEL);
609 	if (!xdev)
610 		return -ENOMEM;
611 
612 	xdev->dev = &pdev->dev;
613 	INIT_LIST_HEAD(&xdev->entities);
614 	INIT_LIST_HEAD(&xdev->dmas);
615 
616 	ret = xvip_composite_v4l2_init(xdev);
617 	if (ret < 0)
618 		return ret;
619 
620 	ret = xvip_graph_init(xdev);
621 	if (ret < 0)
622 		goto error;
623 
624 	platform_set_drvdata(pdev, xdev);
625 
626 	dev_info(xdev->dev, "device registered\n");
627 
628 	return 0;
629 
630 error:
631 	xvip_composite_v4l2_cleanup(xdev);
632 	return ret;
633 }
634 
635 static int xvip_composite_remove(struct platform_device *pdev)
636 {
637 	struct xvip_composite_device *xdev = platform_get_drvdata(pdev);
638 
639 	xvip_graph_cleanup(xdev);
640 	xvip_composite_v4l2_cleanup(xdev);
641 
642 	return 0;
643 }
644 
645 static const struct of_device_id xvip_composite_of_id_table[] = {
646 	{ .compatible = "xlnx,video" },
647 	{ }
648 };
649 MODULE_DEVICE_TABLE(of, xvip_composite_of_id_table);
650 
651 static struct platform_driver xvip_composite_driver = {
652 	.driver = {
653 		.name = "xilinx-video",
654 		.of_match_table = xvip_composite_of_id_table,
655 	},
656 	.probe = xvip_composite_probe,
657 	.remove = xvip_composite_remove,
658 };
659 
660 module_platform_driver(xvip_composite_driver);
661 
662 MODULE_AUTHOR("Laurent Pinchart <laurent.pinchart@ideasonboard.com>");
663 MODULE_DESCRIPTION("Xilinx Video IP Composite Driver");
664 MODULE_LICENSE("GPL v2");
665