1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Xilinx Video IP Composite Device
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/list.h>
13 #include <linux/module.h>
14 #include <linux/of.h>
15 #include <linux/of_graph.h>
16 #include <linux/platform_device.h>
17 #include <linux/slab.h>
18 
19 #include <media/v4l2-async.h>
20 #include <media/v4l2-common.h>
21 #include <media/v4l2-device.h>
22 #include <media/v4l2-fwnode.h>
23 
24 #include "xilinx-dma.h"
25 #include "xilinx-vipp.h"
26 
27 #define XVIPP_DMA_S2MM				0
28 #define XVIPP_DMA_MM2S				1
29 
30 /**
31  * struct xvip_graph_entity - Entity in the video graph
32  * @asd: subdev asynchronous registration information
33  * @entity: media entity, from the corresponding V4L2 subdev
34  * @subdev: V4L2 subdev
35  */
36 struct xvip_graph_entity {
37 	struct v4l2_async_subdev asd; /* must be first */
38 	struct media_entity *entity;
39 	struct v4l2_subdev *subdev;
40 };
41 
42 static inline struct xvip_graph_entity *
43 to_xvip_entity(struct v4l2_async_subdev *asd)
44 {
45 	return container_of(asd, struct xvip_graph_entity, asd);
46 }
47 
48 /* -----------------------------------------------------------------------------
49  * Graph Management
50  */
51 
52 static struct xvip_graph_entity *
53 xvip_graph_find_entity(struct xvip_composite_device *xdev,
54 		       const struct fwnode_handle *fwnode)
55 {
56 	struct xvip_graph_entity *entity;
57 	struct v4l2_async_subdev *asd;
58 
59 	list_for_each_entry(asd, &xdev->notifier.asd_list, asd_list) {
60 		entity = to_xvip_entity(asd);
61 		if (entity->asd.match.fwnode == fwnode)
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 fwnode_handle *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 = fwnode_graph_get_next_endpoint(entity->asd.match.fwnode,
86 						    ep);
87 		if (ep == NULL)
88 			break;
89 
90 		dev_dbg(xdev->dev, "processing endpoint %p\n", ep);
91 
92 		ret = v4l2_fwnode_parse_link(ep, &link);
93 		if (ret < 0) {
94 			dev_err(xdev->dev, "failed to parse link for %p\n",
95 				ep);
96 			continue;
97 		}
98 
99 		/* Skip sink ports, they will be processed from the other end of
100 		 * the link.
101 		 */
102 		if (link.local_port >= local->num_pads) {
103 			dev_err(xdev->dev, "invalid port number %u for %p\n",
104 				link.local_port, 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 %p:%u\n",
114 				link.local_node, link.local_port);
115 			v4l2_fwnode_put_link(&link);
116 			continue;
117 		}
118 
119 		/* Skip DMA engines, they will be processed separately. */
120 		if (link.remote_node == of_fwnode_handle(xdev->dev->of_node)) {
121 			dev_dbg(xdev->dev, "skipping DMA port %p:%u\n",
122 				link.local_node, link.local_port);
123 			v4l2_fwnode_put_link(&link);
124 			continue;
125 		}
126 
127 		/* Find the remote entity. */
128 		ent = xvip_graph_find_entity(xdev, link.remote_node);
129 		if (ent == NULL) {
130 			dev_err(xdev->dev, "no entity found for %p\n",
131 				link.remote_node);
132 			v4l2_fwnode_put_link(&link);
133 			ret = -ENODEV;
134 			break;
135 		}
136 
137 		remote = ent->entity;
138 
139 		if (link.remote_port >= remote->num_pads) {
140 			dev_err(xdev->dev, "invalid port number %u on %p\n",
141 				link.remote_port, link.remote_node);
142 			v4l2_fwnode_put_link(&link);
143 			ret = -EINVAL;
144 			break;
145 		}
146 
147 		remote_pad = &remote->pads[link.remote_port];
148 
149 		v4l2_fwnode_put_link(&link);
150 
151 		/* Create the media link. */
152 		dev_dbg(xdev->dev, "creating %s:%u -> %s:%u link\n",
153 			local->name, local_pad->index,
154 			remote->name, remote_pad->index);
155 
156 		ret = media_create_pad_link(local, local_pad->index,
157 					       remote, remote_pad->index,
158 					       link_flags);
159 		if (ret < 0) {
160 			dev_err(xdev->dev,
161 				"failed to create %s:%u -> %s:%u link\n",
162 				local->name, local_pad->index,
163 				remote->name, remote_pad->index);
164 			break;
165 		}
166 	}
167 
168 	fwnode_handle_put(ep);
169 	return ret;
170 }
171 
172 static struct xvip_dma *
173 xvip_graph_find_dma(struct xvip_composite_device *xdev, unsigned int port)
174 {
175 	struct xvip_dma *dma;
176 
177 	list_for_each_entry(dma, &xdev->dmas, list) {
178 		if (dma->port == port)
179 			return dma;
180 	}
181 
182 	return NULL;
183 }
184 
185 static int xvip_graph_build_dma(struct xvip_composite_device *xdev)
186 {
187 	u32 link_flags = MEDIA_LNK_FL_ENABLED;
188 	struct device_node *node = xdev->dev->of_node;
189 	struct media_entity *source;
190 	struct media_entity *sink;
191 	struct media_pad *source_pad;
192 	struct media_pad *sink_pad;
193 	struct xvip_graph_entity *ent;
194 	struct v4l2_fwnode_link link;
195 	struct device_node *ep = NULL;
196 	struct xvip_dma *dma;
197 	int ret = 0;
198 
199 	dev_dbg(xdev->dev, "creating links for DMA engines\n");
200 
201 	while (1) {
202 		/* Get the next endpoint and parse its link. */
203 		ep = of_graph_get_next_endpoint(node, ep);
204 		if (ep == NULL)
205 			break;
206 
207 		dev_dbg(xdev->dev, "processing endpoint %pOF\n", ep);
208 
209 		ret = v4l2_fwnode_parse_link(of_fwnode_handle(ep), &link);
210 		if (ret < 0) {
211 			dev_err(xdev->dev, "failed to parse link for %pOF\n",
212 				ep);
213 			continue;
214 		}
215 
216 		/* Find the DMA engine. */
217 		dma = xvip_graph_find_dma(xdev, link.local_port);
218 		if (dma == NULL) {
219 			dev_err(xdev->dev, "no DMA engine found for port %u\n",
220 				link.local_port);
221 			v4l2_fwnode_put_link(&link);
222 			ret = -EINVAL;
223 			break;
224 		}
225 
226 		dev_dbg(xdev->dev, "creating link for DMA engine %s\n",
227 			dma->video.name);
228 
229 		/* Find the remote entity. */
230 		ent = xvip_graph_find_entity(xdev, link.remote_node);
231 		if (ent == NULL) {
232 			dev_err(xdev->dev, "no entity found for %pOF\n",
233 				to_of_node(link.remote_node));
234 			v4l2_fwnode_put_link(&link);
235 			ret = -ENODEV;
236 			break;
237 		}
238 
239 		if (link.remote_port >= ent->entity->num_pads) {
240 			dev_err(xdev->dev, "invalid port number %u on %pOF\n",
241 				link.remote_port,
242 				to_of_node(link.remote_node));
243 			v4l2_fwnode_put_link(&link);
244 			ret = -EINVAL;
245 			break;
246 		}
247 
248 		if (dma->pad.flags & MEDIA_PAD_FL_SOURCE) {
249 			source = &dma->video.entity;
250 			source_pad = &dma->pad;
251 			sink = ent->entity;
252 			sink_pad = &sink->pads[link.remote_port];
253 		} else {
254 			source = ent->entity;
255 			source_pad = &source->pads[link.remote_port];
256 			sink = &dma->video.entity;
257 			sink_pad = &dma->pad;
258 		}
259 
260 		v4l2_fwnode_put_link(&link);
261 
262 		/* Create the media link. */
263 		dev_dbg(xdev->dev, "creating %s:%u -> %s:%u link\n",
264 			source->name, source_pad->index,
265 			sink->name, sink_pad->index);
266 
267 		ret = media_create_pad_link(source, source_pad->index,
268 					       sink, sink_pad->index,
269 					       link_flags);
270 		if (ret < 0) {
271 			dev_err(xdev->dev,
272 				"failed to create %s:%u -> %s:%u link\n",
273 				source->name, source_pad->index,
274 				sink->name, sink_pad->index);
275 			break;
276 		}
277 	}
278 
279 	of_node_put(ep);
280 	return ret;
281 }
282 
283 static int xvip_graph_notify_complete(struct v4l2_async_notifier *notifier)
284 {
285 	struct xvip_composite_device *xdev =
286 		container_of(notifier, struct xvip_composite_device, notifier);
287 	struct xvip_graph_entity *entity;
288 	struct v4l2_async_subdev *asd;
289 	int ret;
290 
291 	dev_dbg(xdev->dev, "notify complete, all subdevs registered\n");
292 
293 	/* Create links for every entity. */
294 	list_for_each_entry(asd, &xdev->notifier.asd_list, asd_list) {
295 		entity = to_xvip_entity(asd);
296 		ret = xvip_graph_build_one(xdev, entity);
297 		if (ret < 0)
298 			return ret;
299 	}
300 
301 	/* Create links for DMA channels. */
302 	ret = xvip_graph_build_dma(xdev);
303 	if (ret < 0)
304 		return ret;
305 
306 	ret = v4l2_device_register_subdev_nodes(&xdev->v4l2_dev);
307 	if (ret < 0)
308 		dev_err(xdev->dev, "failed to register subdev nodes\n");
309 
310 	return media_device_register(&xdev->media_dev);
311 }
312 
313 static int xvip_graph_notify_bound(struct v4l2_async_notifier *notifier,
314 				   struct v4l2_subdev *subdev,
315 				   struct v4l2_async_subdev *unused)
316 {
317 	struct xvip_composite_device *xdev =
318 		container_of(notifier, struct xvip_composite_device, notifier);
319 	struct xvip_graph_entity *entity;
320 	struct v4l2_async_subdev *asd;
321 
322 	/* Locate the entity corresponding to the bound subdev and store the
323 	 * subdev pointer.
324 	 */
325 	list_for_each_entry(asd, &xdev->notifier.asd_list, asd_list) {
326 		entity = to_xvip_entity(asd);
327 
328 		if (entity->asd.match.fwnode != subdev->fwnode)
329 			continue;
330 
331 		if (entity->subdev) {
332 			dev_err(xdev->dev, "duplicate subdev for node %p\n",
333 				entity->asd.match.fwnode);
334 			return -EINVAL;
335 		}
336 
337 		dev_dbg(xdev->dev, "subdev %s bound\n", subdev->name);
338 		entity->entity = &subdev->entity;
339 		entity->subdev = subdev;
340 		return 0;
341 	}
342 
343 	dev_err(xdev->dev, "no entity for subdev %s\n", subdev->name);
344 	return -EINVAL;
345 }
346 
347 static const struct v4l2_async_notifier_operations xvip_graph_notify_ops = {
348 	.bound = xvip_graph_notify_bound,
349 	.complete = xvip_graph_notify_complete,
350 };
351 
352 static int xvip_graph_parse_one(struct xvip_composite_device *xdev,
353 				struct fwnode_handle *fwnode)
354 {
355 	struct fwnode_handle *remote;
356 	struct fwnode_handle *ep = NULL;
357 	int ret = 0;
358 
359 	dev_dbg(xdev->dev, "parsing node %p\n", fwnode);
360 
361 	while (1) {
362 		struct xvip_graph_entity *xge;
363 
364 		ep = fwnode_graph_get_next_endpoint(fwnode, ep);
365 		if (ep == NULL)
366 			break;
367 
368 		dev_dbg(xdev->dev, "handling endpoint %p\n", ep);
369 
370 		remote = fwnode_graph_get_remote_port_parent(ep);
371 		if (remote == NULL) {
372 			ret = -EINVAL;
373 			goto err_notifier_cleanup;
374 		}
375 
376 		fwnode_handle_put(ep);
377 
378 		/* Skip entities that we have already processed. */
379 		if (remote == of_fwnode_handle(xdev->dev->of_node) ||
380 		    xvip_graph_find_entity(xdev, remote)) {
381 			fwnode_handle_put(remote);
382 			continue;
383 		}
384 
385 		xge = v4l2_async_nf_add_fwnode(&xdev->notifier, remote,
386 					       struct xvip_graph_entity);
387 		fwnode_handle_put(remote);
388 		if (IS_ERR(xge)) {
389 			ret = PTR_ERR(xge);
390 			goto err_notifier_cleanup;
391 		}
392 	}
393 
394 	return 0;
395 
396 err_notifier_cleanup:
397 	v4l2_async_nf_cleanup(&xdev->notifier);
398 	fwnode_handle_put(ep);
399 	return ret;
400 }
401 
402 static int xvip_graph_parse(struct xvip_composite_device *xdev)
403 {
404 	struct xvip_graph_entity *entity;
405 	struct v4l2_async_subdev *asd;
406 	int ret;
407 
408 	/*
409 	 * Walk the links to parse the full graph. Start by parsing the
410 	 * composite node and then parse entities in turn. The list_for_each
411 	 * loop will handle entities added at the end of the list while walking
412 	 * the links.
413 	 */
414 	ret = xvip_graph_parse_one(xdev, of_fwnode_handle(xdev->dev->of_node));
415 	if (ret < 0)
416 		return 0;
417 
418 	list_for_each_entry(asd, &xdev->notifier.asd_list, asd_list) {
419 		entity = to_xvip_entity(asd);
420 		ret = xvip_graph_parse_one(xdev, entity->asd.match.fwnode);
421 		if (ret < 0) {
422 			v4l2_async_nf_cleanup(&xdev->notifier);
423 			break;
424 		}
425 	}
426 
427 	return ret;
428 }
429 
430 static int xvip_graph_dma_init_one(struct xvip_composite_device *xdev,
431 				   struct device_node *node)
432 {
433 	struct xvip_dma *dma;
434 	enum v4l2_buf_type type;
435 	const char *direction;
436 	unsigned int index;
437 	int ret;
438 
439 	ret = of_property_read_string(node, "direction", &direction);
440 	if (ret < 0)
441 		return ret;
442 
443 	if (strcmp(direction, "input") == 0)
444 		type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
445 	else if (strcmp(direction, "output") == 0)
446 		type = V4L2_BUF_TYPE_VIDEO_OUTPUT;
447 	else
448 		return -EINVAL;
449 
450 	of_property_read_u32(node, "reg", &index);
451 
452 	dma = devm_kzalloc(xdev->dev, sizeof(*dma), GFP_KERNEL);
453 	if (dma == NULL)
454 		return -ENOMEM;
455 
456 	ret = xvip_dma_init(xdev, dma, type, index);
457 	if (ret < 0) {
458 		dev_err(xdev->dev, "%pOF initialization failed\n", node);
459 		return ret;
460 	}
461 
462 	list_add_tail(&dma->list, &xdev->dmas);
463 
464 	xdev->v4l2_caps |= type == V4L2_BUF_TYPE_VIDEO_CAPTURE
465 			 ? V4L2_CAP_VIDEO_CAPTURE : V4L2_CAP_VIDEO_OUTPUT;
466 
467 	return 0;
468 }
469 
470 static int xvip_graph_dma_init(struct xvip_composite_device *xdev)
471 {
472 	struct device_node *ports;
473 	struct device_node *port;
474 	int ret = 0;
475 
476 	ports = of_get_child_by_name(xdev->dev->of_node, "ports");
477 	if (ports == NULL) {
478 		dev_err(xdev->dev, "ports node not present\n");
479 		return -EINVAL;
480 	}
481 
482 	for_each_child_of_node(ports, port) {
483 		ret = xvip_graph_dma_init_one(xdev, port);
484 		if (ret) {
485 			of_node_put(port);
486 			break;
487 		}
488 	}
489 
490 	of_node_put(ports);
491 	return ret;
492 }
493 
494 static void xvip_graph_cleanup(struct xvip_composite_device *xdev)
495 {
496 	struct xvip_dma *dmap;
497 	struct xvip_dma *dma;
498 
499 	v4l2_async_nf_unregister(&xdev->notifier);
500 	v4l2_async_nf_cleanup(&xdev->notifier);
501 
502 	list_for_each_entry_safe(dma, dmap, &xdev->dmas, list) {
503 		xvip_dma_cleanup(dma);
504 		list_del(&dma->list);
505 	}
506 }
507 
508 static int xvip_graph_init(struct xvip_composite_device *xdev)
509 {
510 	int ret;
511 
512 	/* Init the DMA channels. */
513 	ret = xvip_graph_dma_init(xdev);
514 	if (ret < 0) {
515 		dev_err(xdev->dev, "DMA initialization failed\n");
516 		goto done;
517 	}
518 
519 	/* Parse the graph to extract a list of subdevice DT nodes. */
520 	ret = xvip_graph_parse(xdev);
521 	if (ret < 0) {
522 		dev_err(xdev->dev, "graph parsing failed\n");
523 		goto done;
524 	}
525 
526 	if (list_empty(&xdev->notifier.asd_list)) {
527 		dev_err(xdev->dev, "no subdev found in graph\n");
528 		ret = -ENOENT;
529 		goto done;
530 	}
531 
532 	/* Register the subdevices notifier. */
533 	xdev->notifier.ops = &xvip_graph_notify_ops;
534 
535 	ret = v4l2_async_nf_register(&xdev->v4l2_dev, &xdev->notifier);
536 	if (ret < 0) {
537 		dev_err(xdev->dev, "notifier registration failed\n");
538 		goto done;
539 	}
540 
541 	ret = 0;
542 
543 done:
544 	if (ret < 0)
545 		xvip_graph_cleanup(xdev);
546 
547 	return ret;
548 }
549 
550 /* -----------------------------------------------------------------------------
551  * Media Controller and V4L2
552  */
553 
554 static void xvip_composite_v4l2_cleanup(struct xvip_composite_device *xdev)
555 {
556 	v4l2_device_unregister(&xdev->v4l2_dev);
557 	media_device_unregister(&xdev->media_dev);
558 	media_device_cleanup(&xdev->media_dev);
559 }
560 
561 static int xvip_composite_v4l2_init(struct xvip_composite_device *xdev)
562 {
563 	int ret;
564 
565 	xdev->media_dev.dev = xdev->dev;
566 	strscpy(xdev->media_dev.model, "Xilinx Video Composite Device",
567 		sizeof(xdev->media_dev.model));
568 	xdev->media_dev.hw_revision = 0;
569 
570 	media_device_init(&xdev->media_dev);
571 
572 	xdev->v4l2_dev.mdev = &xdev->media_dev;
573 	ret = v4l2_device_register(xdev->dev, &xdev->v4l2_dev);
574 	if (ret < 0) {
575 		dev_err(xdev->dev, "V4L2 device registration failed (%d)\n",
576 			ret);
577 		media_device_cleanup(&xdev->media_dev);
578 		return ret;
579 	}
580 
581 	return 0;
582 }
583 
584 /* -----------------------------------------------------------------------------
585  * Platform Device Driver
586  */
587 
588 static int xvip_composite_probe(struct platform_device *pdev)
589 {
590 	struct xvip_composite_device *xdev;
591 	int ret;
592 
593 	xdev = devm_kzalloc(&pdev->dev, sizeof(*xdev), GFP_KERNEL);
594 	if (!xdev)
595 		return -ENOMEM;
596 
597 	xdev->dev = &pdev->dev;
598 	INIT_LIST_HEAD(&xdev->dmas);
599 	v4l2_async_nf_init(&xdev->notifier);
600 
601 	ret = xvip_composite_v4l2_init(xdev);
602 	if (ret < 0)
603 		return ret;
604 
605 	ret = xvip_graph_init(xdev);
606 	if (ret < 0)
607 		goto error;
608 
609 	platform_set_drvdata(pdev, xdev);
610 
611 	dev_info(xdev->dev, "device registered\n");
612 
613 	return 0;
614 
615 error:
616 	xvip_composite_v4l2_cleanup(xdev);
617 	return ret;
618 }
619 
620 static int xvip_composite_remove(struct platform_device *pdev)
621 {
622 	struct xvip_composite_device *xdev = platform_get_drvdata(pdev);
623 
624 	xvip_graph_cleanup(xdev);
625 	xvip_composite_v4l2_cleanup(xdev);
626 
627 	return 0;
628 }
629 
630 static const struct of_device_id xvip_composite_of_id_table[] = {
631 	{ .compatible = "xlnx,video" },
632 	{ }
633 };
634 MODULE_DEVICE_TABLE(of, xvip_composite_of_id_table);
635 
636 static struct platform_driver xvip_composite_driver = {
637 	.driver = {
638 		.name = "xilinx-video",
639 		.of_match_table = xvip_composite_of_id_table,
640 	},
641 	.probe = xvip_composite_probe,
642 	.remove = xvip_composite_remove,
643 };
644 
645 module_platform_driver(xvip_composite_driver);
646 
647 MODULE_AUTHOR("Laurent Pinchart <laurent.pinchart@ideasonboard.com>");
648 MODULE_DESCRIPTION("Xilinx Video IP Composite Driver");
649 MODULE_LICENSE("GPL v2");
650