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9#include <linux/types.h>
10#include <linux/ioctl.h>
11#include <linux/module.h>
12#include <linux/slab.h>
13#include <linux/videodev2.h>
14#include <media/v4l2-device.h>
15#include <media/v4l2-ctrls.h>
16
17int v4l2_device_register(struct device *dev, struct v4l2_device *v4l2_dev)
18{
19 if (v4l2_dev == NULL)
20 return -EINVAL;
21
22 INIT_LIST_HEAD(&v4l2_dev->subdevs);
23 spin_lock_init(&v4l2_dev->lock);
24 v4l2_prio_init(&v4l2_dev->prio);
25 kref_init(&v4l2_dev->ref);
26 get_device(dev);
27 v4l2_dev->dev = dev;
28 if (dev == NULL) {
29
30 if (WARN_ON(!v4l2_dev->name[0]))
31 return -EINVAL;
32 return 0;
33 }
34
35
36 if (!v4l2_dev->name[0])
37 snprintf(v4l2_dev->name, sizeof(v4l2_dev->name), "%s %s",
38 dev->driver->name, dev_name(dev));
39 if (!dev_get_drvdata(dev))
40 dev_set_drvdata(dev, v4l2_dev);
41 return 0;
42}
43EXPORT_SYMBOL_GPL(v4l2_device_register);
44
45static void v4l2_device_release(struct kref *ref)
46{
47 struct v4l2_device *v4l2_dev =
48 container_of(ref, struct v4l2_device, ref);
49
50 if (v4l2_dev->release)
51 v4l2_dev->release(v4l2_dev);
52}
53
54int v4l2_device_put(struct v4l2_device *v4l2_dev)
55{
56 return kref_put(&v4l2_dev->ref, v4l2_device_release);
57}
58EXPORT_SYMBOL_GPL(v4l2_device_put);
59
60int v4l2_device_set_name(struct v4l2_device *v4l2_dev, const char *basename,
61 atomic_t *instance)
62{
63 int num = atomic_inc_return(instance) - 1;
64 int len = strlen(basename);
65
66 if (basename[len - 1] >= '0' && basename[len - 1] <= '9')
67 snprintf(v4l2_dev->name, sizeof(v4l2_dev->name),
68 "%s-%d", basename, num);
69 else
70 snprintf(v4l2_dev->name, sizeof(v4l2_dev->name),
71 "%s%d", basename, num);
72 return num;
73}
74EXPORT_SYMBOL_GPL(v4l2_device_set_name);
75
76void v4l2_device_disconnect(struct v4l2_device *v4l2_dev)
77{
78 if (v4l2_dev->dev == NULL)
79 return;
80
81 if (dev_get_drvdata(v4l2_dev->dev) == v4l2_dev)
82 dev_set_drvdata(v4l2_dev->dev, NULL);
83 put_device(v4l2_dev->dev);
84 v4l2_dev->dev = NULL;
85}
86EXPORT_SYMBOL_GPL(v4l2_device_disconnect);
87
88void v4l2_device_unregister(struct v4l2_device *v4l2_dev)
89{
90 struct v4l2_subdev *sd, *next;
91
92
93
94 if (v4l2_dev == NULL || !v4l2_dev->name[0])
95 return;
96 v4l2_device_disconnect(v4l2_dev);
97
98
99 list_for_each_entry_safe(sd, next, &v4l2_dev->subdevs, list) {
100 v4l2_device_unregister_subdev(sd);
101 if (sd->flags & V4L2_SUBDEV_FL_IS_I2C)
102 v4l2_i2c_subdev_unregister(sd);
103 else if (sd->flags & V4L2_SUBDEV_FL_IS_SPI)
104 v4l2_spi_subdev_unregister(sd);
105 }
106
107 v4l2_dev->name[0] = '\0';
108}
109EXPORT_SYMBOL_GPL(v4l2_device_unregister);
110
111int v4l2_device_register_subdev(struct v4l2_device *v4l2_dev,
112 struct v4l2_subdev *sd)
113{
114#if defined(CONFIG_MEDIA_CONTROLLER)
115 struct media_entity *entity = &sd->entity;
116#endif
117 int err;
118
119
120 if (!v4l2_dev || !sd || sd->v4l2_dev || !sd->name[0])
121 return -EINVAL;
122
123
124
125
126
127
128
129
130 sd->owner_v4l2_dev = v4l2_dev->dev && v4l2_dev->dev->driver &&
131 sd->owner == v4l2_dev->dev->driver->owner;
132
133 if (!sd->owner_v4l2_dev && !try_module_get(sd->owner))
134 return -ENODEV;
135
136 sd->v4l2_dev = v4l2_dev;
137
138 err = v4l2_ctrl_add_handler(v4l2_dev->ctrl_handler, sd->ctrl_handler,
139 NULL, true);
140 if (err)
141 goto error_module;
142
143#if defined(CONFIG_MEDIA_CONTROLLER)
144
145 if (v4l2_dev->mdev) {
146 err = media_device_register_entity(v4l2_dev->mdev, entity);
147 if (err < 0)
148 goto error_module;
149 }
150#endif
151
152 if (sd->internal_ops && sd->internal_ops->registered) {
153 err = sd->internal_ops->registered(sd);
154 if (err)
155 goto error_unregister;
156 }
157
158 spin_lock(&v4l2_dev->lock);
159 list_add_tail(&sd->list, &v4l2_dev->subdevs);
160 spin_unlock(&v4l2_dev->lock);
161
162 return 0;
163
164error_unregister:
165#if defined(CONFIG_MEDIA_CONTROLLER)
166 media_device_unregister_entity(entity);
167#endif
168error_module:
169 if (!sd->owner_v4l2_dev)
170 module_put(sd->owner);
171 sd->v4l2_dev = NULL;
172 return err;
173}
174EXPORT_SYMBOL_GPL(v4l2_device_register_subdev);
175
176static void v4l2_subdev_release(struct v4l2_subdev *sd)
177{
178 struct module *owner = !sd->owner_v4l2_dev ? sd->owner : NULL;
179
180 if (sd->internal_ops && sd->internal_ops->release)
181 sd->internal_ops->release(sd);
182 module_put(owner);
183}
184
185static void v4l2_device_release_subdev_node(struct video_device *vdev)
186{
187 v4l2_subdev_release(video_get_drvdata(vdev));
188 kfree(vdev);
189}
190
191int v4l2_device_register_subdev_nodes(struct v4l2_device *v4l2_dev)
192{
193 struct video_device *vdev;
194 struct v4l2_subdev *sd;
195 int err;
196
197
198
199
200 list_for_each_entry(sd, &v4l2_dev->subdevs, list) {
201 if (!(sd->flags & V4L2_SUBDEV_FL_HAS_DEVNODE))
202 continue;
203
204 if (sd->devnode)
205 continue;
206
207 vdev = kzalloc(sizeof(*vdev), GFP_KERNEL);
208 if (!vdev) {
209 err = -ENOMEM;
210 goto clean_up;
211 }
212
213 video_set_drvdata(vdev, sd);
214 strscpy(vdev->name, sd->name, sizeof(vdev->name));
215 vdev->dev_parent = sd->dev;
216 vdev->v4l2_dev = v4l2_dev;
217 vdev->fops = &v4l2_subdev_fops;
218 vdev->release = v4l2_device_release_subdev_node;
219 vdev->ctrl_handler = sd->ctrl_handler;
220 err = __video_register_device(vdev, VFL_TYPE_SUBDEV, -1, 1,
221 sd->owner);
222 if (err < 0) {
223 kfree(vdev);
224 goto clean_up;
225 }
226 sd->devnode = vdev;
227#if defined(CONFIG_MEDIA_CONTROLLER)
228 sd->entity.info.dev.major = VIDEO_MAJOR;
229 sd->entity.info.dev.minor = vdev->minor;
230
231
232 if (vdev->v4l2_dev->mdev) {
233 struct media_link *link;
234
235 link = media_create_intf_link(&sd->entity,
236 &vdev->intf_devnode->intf,
237 MEDIA_LNK_FL_ENABLED |
238 MEDIA_LNK_FL_IMMUTABLE);
239 if (!link) {
240 err = -ENOMEM;
241 goto clean_up;
242 }
243 }
244#endif
245 }
246 return 0;
247
248clean_up:
249 list_for_each_entry(sd, &v4l2_dev->subdevs, list) {
250 if (!sd->devnode)
251 break;
252 video_unregister_device(sd->devnode);
253 }
254
255 return err;
256}
257EXPORT_SYMBOL_GPL(v4l2_device_register_subdev_nodes);
258
259void v4l2_device_unregister_subdev(struct v4l2_subdev *sd)
260{
261 struct v4l2_device *v4l2_dev;
262
263
264 if (sd == NULL || sd->v4l2_dev == NULL)
265 return;
266
267 v4l2_dev = sd->v4l2_dev;
268
269 spin_lock(&v4l2_dev->lock);
270 list_del(&sd->list);
271 spin_unlock(&v4l2_dev->lock);
272
273 if (sd->internal_ops && sd->internal_ops->unregistered)
274 sd->internal_ops->unregistered(sd);
275 sd->v4l2_dev = NULL;
276
277#if defined(CONFIG_MEDIA_CONTROLLER)
278 if (v4l2_dev->mdev) {
279
280
281
282
283 media_device_unregister_entity(&sd->entity);
284 }
285#endif
286 if (sd->devnode)
287 video_unregister_device(sd->devnode);
288 else
289 v4l2_subdev_release(sd);
290}
291EXPORT_SYMBOL_GPL(v4l2_device_unregister_subdev);
292