Commit | Line | Data |
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e9e31049 GL |
1 | /* |
2 | * V4L2 asynchronous subdevice registration API | |
3 | * | |
4 | * Copyright (C) 2012-2013, Guennadi Liakhovetski <g.liakhovetski@gmx.de> | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or modify | |
7 | * it under the terms of the GNU General Public License version 2 as | |
8 | * published by the Free Software Foundation. | |
9 | */ | |
10 | ||
11 | #include <linux/device.h> | |
12 | #include <linux/err.h> | |
13 | #include <linux/i2c.h> | |
14 | #include <linux/list.h> | |
15 | #include <linux/module.h> | |
16 | #include <linux/mutex.h> | |
17 | #include <linux/platform_device.h> | |
18 | #include <linux/slab.h> | |
19 | #include <linux/types.h> | |
20 | ||
21 | #include <media/v4l2-async.h> | |
22 | #include <media/v4l2-device.h> | |
23 | #include <media/v4l2-subdev.h> | |
24 | ||
25 | static bool match_i2c(struct device *dev, struct v4l2_async_subdev *asd) | |
26 | { | |
fe05e141 | 27 | #if IS_ENABLED(CONFIG_I2C) |
e9e31049 GL |
28 | struct i2c_client *client = i2c_verify_client(dev); |
29 | return client && | |
e9e31049 GL |
30 | asd->match.i2c.adapter_id == client->adapter->nr && |
31 | asd->match.i2c.address == client->addr; | |
fe05e141 GL |
32 | #else |
33 | return false; | |
34 | #endif | |
e9e31049 GL |
35 | } |
36 | ||
cfca7644 | 37 | static bool match_devname(struct device *dev, struct v4l2_async_subdev *asd) |
e9e31049 | 38 | { |
cfca7644 | 39 | return !strcmp(asd->match.device_name.name, dev_name(dev)); |
e9e31049 GL |
40 | } |
41 | ||
e7359f8e SN |
42 | static bool match_of(struct device *dev, struct v4l2_async_subdev *asd) |
43 | { | |
44 | return dev->of_node == asd->match.of.node; | |
45 | } | |
46 | ||
e9e31049 GL |
47 | static LIST_HEAD(subdev_list); |
48 | static LIST_HEAD(notifier_list); | |
49 | static DEFINE_MUTEX(list_lock); | |
50 | ||
51 | static struct v4l2_async_subdev *v4l2_async_belongs(struct v4l2_async_notifier *notifier, | |
b426b3a6 | 52 | struct v4l2_subdev *sd) |
e9e31049 | 53 | { |
e9e31049 | 54 | struct v4l2_async_subdev *asd; |
b426b3a6 | 55 | bool (*match)(struct device *, struct v4l2_async_subdev *); |
e9e31049 GL |
56 | |
57 | list_for_each_entry(asd, ¬ifier->waiting, list) { | |
58 | /* bus_type has been verified valid before */ | |
cfca7644 SN |
59 | switch (asd->match_type) { |
60 | case V4L2_ASYNC_MATCH_CUSTOM: | |
e9e31049 GL |
61 | match = asd->match.custom.match; |
62 | if (!match) | |
63 | /* Match always */ | |
64 | return asd; | |
65 | break; | |
cfca7644 SN |
66 | case V4L2_ASYNC_MATCH_DEVNAME: |
67 | match = match_devname; | |
e9e31049 | 68 | break; |
cfca7644 | 69 | case V4L2_ASYNC_MATCH_I2C: |
e9e31049 GL |
70 | match = match_i2c; |
71 | break; | |
e7359f8e SN |
72 | case V4L2_ASYNC_MATCH_OF: |
73 | match = match_of; | |
74 | break; | |
e9e31049 GL |
75 | default: |
76 | /* Cannot happen, unless someone breaks us */ | |
77 | WARN_ON(true); | |
78 | return NULL; | |
79 | } | |
80 | ||
81 | /* match cannot be NULL here */ | |
82 | if (match(sd->dev, asd)) | |
83 | return asd; | |
84 | } | |
85 | ||
86 | return NULL; | |
87 | } | |
88 | ||
89 | static int v4l2_async_test_notify(struct v4l2_async_notifier *notifier, | |
b426b3a6 | 90 | struct v4l2_subdev *sd, |
e9e31049 GL |
91 | struct v4l2_async_subdev *asd) |
92 | { | |
e9e31049 GL |
93 | int ret; |
94 | ||
95 | /* Remove from the waiting list */ | |
96 | list_del(&asd->list); | |
b426b3a6 SN |
97 | sd->asd = asd; |
98 | sd->notifier = notifier; | |
e9e31049 GL |
99 | |
100 | if (notifier->bound) { | |
101 | ret = notifier->bound(notifier, sd, asd); | |
102 | if (ret < 0) | |
103 | return ret; | |
104 | } | |
105 | /* Move from the global subdevice list to notifier's done */ | |
b426b3a6 | 106 | list_move(&sd->async_list, ¬ifier->done); |
e9e31049 GL |
107 | |
108 | ret = v4l2_device_register_subdev(notifier->v4l2_dev, sd); | |
109 | if (ret < 0) { | |
110 | if (notifier->unbind) | |
111 | notifier->unbind(notifier, sd, asd); | |
112 | return ret; | |
113 | } | |
114 | ||
115 | if (list_empty(¬ifier->waiting) && notifier->complete) | |
116 | return notifier->complete(notifier); | |
117 | ||
118 | return 0; | |
119 | } | |
120 | ||
b426b3a6 | 121 | static void v4l2_async_cleanup(struct v4l2_subdev *sd) |
e9e31049 | 122 | { |
e9e31049 | 123 | v4l2_device_unregister_subdev(sd); |
b426b3a6 SN |
124 | /* Subdevice driver will reprobe and put the subdev back onto the list */ |
125 | list_del_init(&sd->async_list); | |
126 | sd->asd = NULL; | |
e9e31049 GL |
127 | sd->dev = NULL; |
128 | } | |
129 | ||
130 | int v4l2_async_notifier_register(struct v4l2_device *v4l2_dev, | |
131 | struct v4l2_async_notifier *notifier) | |
132 | { | |
b426b3a6 | 133 | struct v4l2_subdev *sd, *tmp; |
e9e31049 GL |
134 | struct v4l2_async_subdev *asd; |
135 | int i; | |
136 | ||
137 | if (!notifier->num_subdevs || notifier->num_subdevs > V4L2_MAX_SUBDEVS) | |
138 | return -EINVAL; | |
139 | ||
140 | notifier->v4l2_dev = v4l2_dev; | |
141 | INIT_LIST_HEAD(¬ifier->waiting); | |
142 | INIT_LIST_HEAD(¬ifier->done); | |
143 | ||
144 | for (i = 0; i < notifier->num_subdevs; i++) { | |
e8419d08 | 145 | asd = notifier->subdevs[i]; |
e9e31049 | 146 | |
cfca7644 SN |
147 | switch (asd->match_type) { |
148 | case V4L2_ASYNC_MATCH_CUSTOM: | |
149 | case V4L2_ASYNC_MATCH_DEVNAME: | |
150 | case V4L2_ASYNC_MATCH_I2C: | |
e7359f8e | 151 | case V4L2_ASYNC_MATCH_OF: |
e9e31049 GL |
152 | break; |
153 | default: | |
154 | dev_err(notifier->v4l2_dev ? notifier->v4l2_dev->dev : NULL, | |
cfca7644 SN |
155 | "Invalid match type %u on %p\n", |
156 | asd->match_type, asd); | |
e9e31049 GL |
157 | return -EINVAL; |
158 | } | |
159 | list_add_tail(&asd->list, ¬ifier->waiting); | |
160 | } | |
161 | ||
162 | mutex_lock(&list_lock); | |
163 | ||
164 | /* Keep also completed notifiers on the list */ | |
165 | list_add(¬ifier->list, ¬ifier_list); | |
166 | ||
b426b3a6 | 167 | list_for_each_entry_safe(sd, tmp, &subdev_list, async_list) { |
e9e31049 GL |
168 | int ret; |
169 | ||
b426b3a6 | 170 | asd = v4l2_async_belongs(notifier, sd); |
e9e31049 GL |
171 | if (!asd) |
172 | continue; | |
173 | ||
b426b3a6 | 174 | ret = v4l2_async_test_notify(notifier, sd, asd); |
e9e31049 GL |
175 | if (ret < 0) { |
176 | mutex_unlock(&list_lock); | |
177 | return ret; | |
178 | } | |
179 | } | |
180 | ||
181 | mutex_unlock(&list_lock); | |
182 | ||
183 | return 0; | |
184 | } | |
185 | EXPORT_SYMBOL(v4l2_async_notifier_register); | |
186 | ||
187 | void v4l2_async_notifier_unregister(struct v4l2_async_notifier *notifier) | |
188 | { | |
b426b3a6 | 189 | struct v4l2_subdev *sd, *tmp; |
e9e31049 GL |
190 | unsigned int notif_n_subdev = notifier->num_subdevs; |
191 | unsigned int n_subdev = min(notif_n_subdev, V4L2_MAX_SUBDEVS); | |
192 | struct device *dev[n_subdev]; | |
193 | int i = 0; | |
194 | ||
8e3fbfee LP |
195 | if (!notifier->v4l2_dev) |
196 | return; | |
197 | ||
e9e31049 GL |
198 | mutex_lock(&list_lock); |
199 | ||
200 | list_del(¬ifier->list); | |
201 | ||
b426b3a6 | 202 | list_for_each_entry_safe(sd, tmp, ¬ifier->done, list) { |
e9e31049 GL |
203 | dev[i] = get_device(sd->dev); |
204 | ||
b426b3a6 | 205 | v4l2_async_cleanup(sd); |
e9e31049 GL |
206 | |
207 | /* If we handled USB devices, we'd have to lock the parent too */ | |
208 | device_release_driver(dev[i++]); | |
209 | ||
210 | if (notifier->unbind) | |
b426b3a6 | 211 | notifier->unbind(notifier, sd, sd->asd); |
e9e31049 GL |
212 | } |
213 | ||
214 | mutex_unlock(&list_lock); | |
215 | ||
216 | while (i--) { | |
217 | struct device *d = dev[i]; | |
218 | ||
219 | if (d && device_attach(d) < 0) { | |
220 | const char *name = "(none)"; | |
221 | int lock = device_trylock(d); | |
222 | ||
223 | if (lock && d->driver) | |
224 | name = d->driver->name; | |
225 | dev_err(d, "Failed to re-probe to %s\n", name); | |
226 | if (lock) | |
227 | device_unlock(d); | |
228 | } | |
229 | put_device(d); | |
230 | } | |
8e3fbfee LP |
231 | |
232 | notifier->v4l2_dev = NULL; | |
233 | ||
e9e31049 GL |
234 | /* |
235 | * Don't care about the waiting list, it is initialised and populated | |
236 | * upon notifier registration. | |
237 | */ | |
238 | } | |
239 | EXPORT_SYMBOL(v4l2_async_notifier_unregister); | |
240 | ||
241 | int v4l2_async_register_subdev(struct v4l2_subdev *sd) | |
242 | { | |
e9e31049 GL |
243 | struct v4l2_async_notifier *notifier; |
244 | ||
245 | mutex_lock(&list_lock); | |
246 | ||
b426b3a6 | 247 | INIT_LIST_HEAD(&sd->async_list); |
e9e31049 GL |
248 | |
249 | list_for_each_entry(notifier, ¬ifier_list, list) { | |
b426b3a6 | 250 | struct v4l2_async_subdev *asd = v4l2_async_belongs(notifier, sd); |
e9e31049 | 251 | if (asd) { |
b426b3a6 | 252 | int ret = v4l2_async_test_notify(notifier, sd, asd); |
e9e31049 GL |
253 | mutex_unlock(&list_lock); |
254 | return ret; | |
255 | } | |
256 | } | |
257 | ||
258 | /* None matched, wait for hot-plugging */ | |
b426b3a6 | 259 | list_add(&sd->async_list, &subdev_list); |
e9e31049 GL |
260 | |
261 | mutex_unlock(&list_lock); | |
262 | ||
263 | return 0; | |
264 | } | |
265 | EXPORT_SYMBOL(v4l2_async_register_subdev); | |
266 | ||
267 | void v4l2_async_unregister_subdev(struct v4l2_subdev *sd) | |
268 | { | |
b426b3a6 | 269 | struct v4l2_async_notifier *notifier = sd->notifier; |
e9e31049 | 270 | |
b426b3a6 SN |
271 | if (!sd->asd) { |
272 | if (!list_empty(&sd->async_list)) | |
273 | v4l2_async_cleanup(sd); | |
e9e31049 GL |
274 | return; |
275 | } | |
276 | ||
277 | mutex_lock(&list_lock); | |
278 | ||
b426b3a6 | 279 | list_add(&sd->asd->list, ¬ifier->waiting); |
e9e31049 | 280 | |
b426b3a6 | 281 | v4l2_async_cleanup(sd); |
e9e31049 GL |
282 | |
283 | if (notifier->unbind) | |
b426b3a6 | 284 | notifier->unbind(notifier, sd, sd->asd); |
e9e31049 GL |
285 | |
286 | mutex_unlock(&list_lock); | |
287 | } | |
288 | EXPORT_SYMBOL(v4l2_async_unregister_subdev); |