2 V4L2 device support header.
4 Copyright (C) 2008 Hans Verkuil <hverkuil@xs4all.nl>
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
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18 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
21 #ifndef _V4L2_DEVICE_H
22 #define _V4L2_DEVICE_H
24 #include <media/media-device.h>
25 #include <media/v4l2-subdev.h>
26 #include <media/v4l2-dev.h>
28 #define V4L2_DEVICE_NAME_SIZE (20 + 16)
30 struct v4l2_ctrl_handler
;
33 * struct v4l2_device - main struct to for V4L2 device drivers
35 * @dev: pointer to struct device.
36 * @mdev: pointer to struct media_device
37 * @subdevs: used to keep track of the registered subdevs
38 * @lock: lock this struct; can be used by the driver as well
39 * if this struct is embedded into a larger struct.
40 * @name: unique device name, by default the driver name + bus ID
41 * @notify: notify callback called by some sub-devices.
42 * @ctrl_handler: The control handler. May be %NULL.
43 * @prio: Device's priority state
44 * @ref: Keep track of the references to this struct.
45 * @release: Release function that is called when the ref count
48 * Each instance of a V4L2 device should create the v4l2_device struct,
49 * either stand-alone or embedded in a larger struct.
51 * It allows easy access to sub-devices (see v4l2-subdev.h) and provides
52 * basic V4L2 device-level support.
56 * #) @dev->driver_data points to this struct.
57 * #) @dev might be %NULL if there is no parent device
62 #if defined(CONFIG_MEDIA_CONTROLLER)
63 struct media_device
*mdev
;
65 struct list_head subdevs
;
67 char name
[V4L2_DEVICE_NAME_SIZE
];
68 void (*notify
)(struct v4l2_subdev
*sd
,
69 unsigned int notification
, void *arg
);
70 struct v4l2_ctrl_handler
*ctrl_handler
;
71 struct v4l2_prio_state prio
;
73 void (*release
)(struct v4l2_device
*v4l2_dev
);
77 * v4l2_device_get - gets a V4L2 device reference
79 * @v4l2_dev: pointer to struct &v4l2_device
81 * This is an ancillary routine meant to increment the usage for the
82 * struct &v4l2_device pointed by @v4l2_dev.
84 static inline void v4l2_device_get(struct v4l2_device
*v4l2_dev
)
86 kref_get(&v4l2_dev
->ref
);
90 * v4l2_device_put - putss a V4L2 device reference
92 * @v4l2_dev: pointer to struct &v4l2_device
94 * This is an ancillary routine meant to decrement the usage for the
95 * struct &v4l2_device pointed by @v4l2_dev.
97 int v4l2_device_put(struct v4l2_device
*v4l2_dev
);
100 * v4l2_device_register - Initialize v4l2_dev and make @dev->driver_data
101 * point to @v4l2_dev.
103 * @dev: pointer to struct &device
104 * @v4l2_dev: pointer to struct &v4l2_device
107 * @dev may be %NULL in rare cases (ISA devices).
108 * In such case the caller must fill in the @v4l2_dev->name field
109 * before calling this function.
111 int __must_check
v4l2_device_register(struct device
*dev
,
112 struct v4l2_device
*v4l2_dev
);
115 * v4l2_device_set_name - Optional function to initialize the
116 * name field of struct &v4l2_device
118 * @v4l2_dev: pointer to struct &v4l2_device
119 * @basename: base name for the device name
120 * @instance: pointer to a static atomic_t var with the instance usage for
123 * v4l2_device_set_name() initializes the name field of struct &v4l2_device
124 * using the driver name and a driver-global atomic_t instance.
126 * This function will increment the instance counter and returns the
127 * instance value used in the name.
131 * static atomic_t drv_instance = ATOMIC_INIT(0);
135 * instance = v4l2_device_set_name(&\ v4l2_dev, "foo", &\ drv_instance);
137 * The first time this is called the name field will be set to foo0 and
138 * this function returns 0. If the name ends with a digit (e.g. cx18),
139 * then the name will be set to cx18-0 since cx180 would look really odd.
141 int v4l2_device_set_name(struct v4l2_device
*v4l2_dev
, const char *basename
,
145 * v4l2_device_disconnect - Change V4L2 device state to disconnected.
147 * @v4l2_dev: pointer to struct v4l2_device
149 * Should be called when the USB parent disconnects.
150 * Since the parent disappears, this ensures that @v4l2_dev doesn't have
151 * an invalid parent pointer.
153 * .. note:: This function sets @v4l2_dev->dev to NULL.
155 void v4l2_device_disconnect(struct v4l2_device
*v4l2_dev
);
158 * v4l2_device_unregister - Unregister all sub-devices and any other
159 * resources related to @v4l2_dev.
161 * @v4l2_dev: pointer to struct v4l2_device
163 void v4l2_device_unregister(struct v4l2_device
*v4l2_dev
);
166 * v4l2_device_register_subdev - Registers a subdev with a v4l2 device.
168 * @v4l2_dev: pointer to struct &v4l2_device
169 * @sd: pointer to struct &v4l2_subdev
171 * While registered, the subdev module is marked as in-use.
173 * An error is returned if the module is no longer loaded on any attempts
176 int __must_check
v4l2_device_register_subdev(struct v4l2_device
*v4l2_dev
,
177 struct v4l2_subdev
*sd
);
180 * v4l2_device_unregister_subdev - Unregisters a subdev with a v4l2 device.
182 * @sd: pointer to struct &v4l2_subdev
186 * Can also be called if the subdev wasn't registered. In such
187 * case, it will do nothing.
189 void v4l2_device_unregister_subdev(struct v4l2_subdev
*sd
);
192 * v4l2_device_register_subdev_nodes - Registers device nodes for all subdevs
193 * of the v4l2 device that are marked with
194 * the %V4L2_SUBDEV_FL_HAS_DEVNODE flag.
196 * @v4l2_dev: pointer to struct v4l2_device
199 v4l2_device_register_subdev_nodes(struct v4l2_device
*v4l2_dev
);
202 * v4l2_subdev_notify - Sends a notification to v4l2_device.
204 * @sd: pointer to struct &v4l2_subdev
205 * @notification: type of notification. Please notice that the notification
206 * type is driver-specific.
207 * @arg: arguments for the notification. Those are specific to each
210 static inline void v4l2_subdev_notify(struct v4l2_subdev
*sd
,
211 unsigned int notification
, void *arg
)
213 if (sd
&& sd
->v4l2_dev
&& sd
->v4l2_dev
->notify
)
214 sd
->v4l2_dev
->notify(sd
, notification
, arg
);
217 /* Iterate over all subdevs. */
218 #define v4l2_device_for_each_subdev(sd, v4l2_dev) \
219 list_for_each_entry(sd, &(v4l2_dev)->subdevs, list)
221 /* Call the specified callback for all subdevs matching the condition.
222 Ignore any errors. Note that you cannot add or delete a subdev
223 while walking the subdevs list. */
224 #define __v4l2_device_call_subdevs_p(v4l2_dev, sd, cond, o, f, args...) \
226 list_for_each_entry((sd), &(v4l2_dev)->subdevs, list) \
227 if ((cond) && (sd)->ops->o && (sd)->ops->o->f) \
228 (sd)->ops->o->f((sd) , ##args); \
231 #define __v4l2_device_call_subdevs(v4l2_dev, cond, o, f, args...) \
233 struct v4l2_subdev *__sd; \
235 __v4l2_device_call_subdevs_p(v4l2_dev, __sd, cond, o, \
239 /* Call the specified callback for all subdevs matching the condition.
240 If the callback returns an error other than 0 or -ENOIOCTLCMD, then
241 return with that error code. Note that you cannot add or delete a
242 subdev while walking the subdevs list. */
243 #define __v4l2_device_call_subdevs_until_err_p(v4l2_dev, sd, cond, o, f, args...) \
247 list_for_each_entry((sd), &(v4l2_dev)->subdevs, list) { \
248 if ((cond) && (sd)->ops->o && (sd)->ops->o->f) \
249 __err = (sd)->ops->o->f((sd) , ##args); \
250 if (__err && __err != -ENOIOCTLCMD) \
253 (__err == -ENOIOCTLCMD) ? 0 : __err; \
256 #define __v4l2_device_call_subdevs_until_err(v4l2_dev, cond, o, f, args...) \
258 struct v4l2_subdev *__sd; \
259 __v4l2_device_call_subdevs_until_err_p(v4l2_dev, __sd, cond, o, \
263 /* Call the specified callback for all subdevs matching grp_id (if 0, then
264 match them all). Ignore any errors. Note that you cannot add or delete
265 a subdev while walking the subdevs list. */
266 #define v4l2_device_call_all(v4l2_dev, grpid, o, f, args...) \
268 struct v4l2_subdev *__sd; \
270 __v4l2_device_call_subdevs_p(v4l2_dev, __sd, \
271 !(grpid) || __sd->grp_id == (grpid), o, f , \
275 /* Call the specified callback for all subdevs matching grp_id (if 0, then
276 match them all). If the callback returns an error other than 0 or
277 -ENOIOCTLCMD, then return with that error code. Note that you cannot
278 add or delete a subdev while walking the subdevs list. */
279 #define v4l2_device_call_until_err(v4l2_dev, grpid, o, f, args...) \
281 struct v4l2_subdev *__sd; \
282 __v4l2_device_call_subdevs_until_err_p(v4l2_dev, __sd, \
283 !(grpid) || __sd->grp_id == (grpid), o, f , \
288 * Call the specified callback for all subdevs where grp_id & grpmsk != 0
289 * (if grpmsk == `0, then match them all). Ignore any errors. Note that you
290 * cannot add or delete a subdev while walking the subdevs list.
292 #define v4l2_device_mask_call_all(v4l2_dev, grpmsk, o, f, args...) \
294 struct v4l2_subdev *__sd; \
296 __v4l2_device_call_subdevs_p(v4l2_dev, __sd, \
297 !(grpmsk) || (__sd->grp_id & (grpmsk)), o, f , \
302 * Call the specified callback for all subdevs where grp_id & grpmsk != 0
303 * (if grpmsk == 0, then match them all). If the callback returns an error
304 * other than 0 or %-ENOIOCTLCMD, then return with that error code. Note that
305 * you cannot add or delete a subdev while walking the subdevs list.
307 #define v4l2_device_mask_call_until_err(v4l2_dev, grpmsk, o, f, args...) \
309 struct v4l2_subdev *__sd; \
310 __v4l2_device_call_subdevs_until_err_p(v4l2_dev, __sd, \
311 !(grpmsk) || (__sd->grp_id & (grpmsk)), o, f , \
316 * Does any subdev with matching grpid (or all if grpid == 0) has the given
319 #define v4l2_device_has_op(v4l2_dev, grpid, o, f) \
321 struct v4l2_subdev *__sd; \
322 bool __result = false; \
323 list_for_each_entry(__sd, &(v4l2_dev)->subdevs, list) { \
324 if ((grpid) && __sd->grp_id != (grpid)) \
326 if (v4l2_subdev_has_op(__sd, o, f)) { \
335 * Does any subdev with matching grpmsk (or all if grpmsk == 0) has the given
338 #define v4l2_device_mask_has_op(v4l2_dev, grpmsk, o, f) \
340 struct v4l2_subdev *__sd; \
341 bool __result = false; \
342 list_for_each_entry(__sd, &(v4l2_dev)->subdevs, list) { \
343 if ((grpmsk) && !(__sd->grp_id & (grpmsk))) \
345 if (v4l2_subdev_has_op(__sd, o, f)) { \