xref: /linux/drivers/media/usb/uvc/uvc_entity.c (revision 3d0fe49454652117522f60bfbefb978ba0e5300b)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *      uvc_entity.c  --  USB Video Class driver
4  *
5  *      Copyright (C) 2005-2011
6  *          Laurent Pinchart (laurent.pinchart@ideasonboard.com)
7  */
8 
9 #include <linux/kernel.h>
10 #include <linux/list.h>
11 #include <linux/videodev2.h>
12 
13 #include <media/v4l2-common.h>
14 
15 #include "uvcvideo.h"
16 
17 static int uvc_mc_create_links(struct uvc_video_chain *chain,
18 				    struct uvc_entity *entity)
19 {
20 	const u32 flags = MEDIA_LNK_FL_ENABLED | MEDIA_LNK_FL_IMMUTABLE;
21 	struct media_entity *sink;
22 	unsigned int i;
23 	int ret;
24 
25 	sink = (UVC_ENTITY_TYPE(entity) == UVC_TT_STREAMING)
26 	     ? (entity->vdev ? &entity->vdev->entity : NULL)
27 	     : &entity->subdev.entity;
28 	if (sink == NULL)
29 		return 0;
30 
31 	for (i = 0; i < entity->num_pads; ++i) {
32 		struct media_entity *source;
33 		struct uvc_entity *remote;
34 		u8 remote_pad;
35 
36 		if (!(entity->pads[i].flags & MEDIA_PAD_FL_SINK))
37 			continue;
38 
39 		remote = uvc_entity_by_id(chain->dev, entity->baSourceID[i]);
40 		if (remote == NULL || remote->num_pads == 0)
41 			return -EINVAL;
42 
43 		source = (UVC_ENTITY_TYPE(remote) == UVC_TT_STREAMING)
44 		       ? (remote->vdev ? &remote->vdev->entity : NULL)
45 		       : &remote->subdev.entity;
46 		if (source == NULL)
47 			continue;
48 
49 		remote_pad = remote->num_pads - 1;
50 		ret = media_create_pad_link(source, remote_pad,
51 					       sink, i, flags);
52 		if (ret < 0)
53 			return ret;
54 	}
55 
56 	return 0;
57 }
58 
59 static const struct v4l2_subdev_ops uvc_subdev_ops = {
60 };
61 
62 void uvc_mc_cleanup_entity(struct uvc_entity *entity)
63 {
64 	if (UVC_ENTITY_TYPE(entity) != UVC_TT_STREAMING)
65 		media_entity_cleanup(&entity->subdev.entity);
66 	else if (entity->vdev != NULL)
67 		media_entity_cleanup(&entity->vdev->entity);
68 }
69 
70 static int uvc_mc_init_entity(struct uvc_video_chain *chain,
71 			      struct uvc_entity *entity)
72 {
73 	int ret;
74 
75 	if (UVC_ENTITY_TYPE(entity) != UVC_TT_STREAMING) {
76 		u32 function;
77 
78 		v4l2_subdev_init(&entity->subdev, &uvc_subdev_ops);
79 		strscpy(entity->subdev.name, entity->name,
80 			sizeof(entity->subdev.name));
81 
82 		switch (UVC_ENTITY_TYPE(entity)) {
83 		case UVC_VC_SELECTOR_UNIT:
84 			function = MEDIA_ENT_F_VID_MUX;
85 			break;
86 		case UVC_VC_PROCESSING_UNIT:
87 		case UVC_VC_EXTENSION_UNIT:
88 			/* For lack of a better option. */
89 			function = MEDIA_ENT_F_PROC_VIDEO_PIXEL_FORMATTER;
90 			break;
91 		case UVC_COMPOSITE_CONNECTOR:
92 		case UVC_COMPONENT_CONNECTOR:
93 			function = MEDIA_ENT_F_CONN_COMPOSITE;
94 			break;
95 		case UVC_SVIDEO_CONNECTOR:
96 			function = MEDIA_ENT_F_CONN_SVIDEO;
97 			break;
98 		case UVC_ITT_CAMERA:
99 			function = MEDIA_ENT_F_CAM_SENSOR;
100 			break;
101 		case UVC_TT_VENDOR_SPECIFIC:
102 		case UVC_ITT_VENDOR_SPECIFIC:
103 		case UVC_ITT_MEDIA_TRANSPORT_INPUT:
104 		case UVC_OTT_VENDOR_SPECIFIC:
105 		case UVC_OTT_DISPLAY:
106 		case UVC_OTT_MEDIA_TRANSPORT_OUTPUT:
107 		case UVC_EXTERNAL_VENDOR_SPECIFIC:
108 		case UVC_EXT_GPIO_UNIT:
109 		default:
110 			function = MEDIA_ENT_F_V4L2_SUBDEV_UNKNOWN;
111 			break;
112 		}
113 
114 		entity->subdev.entity.function = function;
115 
116 		ret = media_entity_pads_init(&entity->subdev.entity,
117 					entity->num_pads, entity->pads);
118 
119 		if (ret < 0)
120 			return ret;
121 
122 		ret = v4l2_device_register_subdev(&chain->dev->vdev,
123 						  &entity->subdev);
124 	} else if (entity->vdev != NULL) {
125 		ret = media_entity_pads_init(&entity->vdev->entity,
126 					entity->num_pads, entity->pads);
127 		if (entity->flags & UVC_ENTITY_FLAG_DEFAULT)
128 			entity->vdev->entity.flags |= MEDIA_ENT_FL_DEFAULT;
129 	} else
130 		ret = 0;
131 
132 	return ret;
133 }
134 
135 int uvc_mc_register_entities(struct uvc_video_chain *chain)
136 {
137 	struct uvc_entity *entity;
138 	int ret;
139 
140 	list_for_each_entry(entity, &chain->entities, chain) {
141 		ret = uvc_mc_init_entity(chain, entity);
142 		if (ret < 0) {
143 			dev_info(&chain->dev->udev->dev,
144 				 "Failed to initialize entity for entity %u\n",
145 				 entity->id);
146 			return ret;
147 		}
148 	}
149 
150 	list_for_each_entry(entity, &chain->entities, chain) {
151 		ret = uvc_mc_create_links(chain, entity);
152 		if (ret < 0) {
153 			dev_info(&chain->dev->udev->dev,
154 				 "Failed to create links for entity %u\n",
155 				 entity->id);
156 			return ret;
157 		}
158 	}
159 
160 	return 0;
161 }
162