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1/*
2 V4L2 device support header.
3
4 Copyright (C) 2008 Hans Verkuil <hverkuil@xs4all.nl>
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 as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
10
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.
15
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software
18 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 */
20
21#ifndef _V4L2_DEVICE_H
22#define _V4L2_DEVICE_H
23
24#include <media/media-device.h>
25#include <media/v4l2-subdev.h>
26#include <media/v4l2-dev.h>
27
28/* Each instance of a V4L2 device should create the v4l2_device struct,
29 either stand-alone or embedded in a larger struct.
30
31 It allows easy access to sub-devices (see v4l2-subdev.h) and provides
32 basic V4L2 device-level support.
33 */
34
35#define V4L2_DEVICE_NAME_SIZE (20 + 16)
36
37struct v4l2_ctrl_handler;
38
39struct v4l2_device {
40 /* dev->driver_data points to this struct.
41 Note: dev might be NULL if there is no parent device
42 as is the case with e.g. ISA devices. */
43 struct device *dev;
44#if defined(CONFIG_MEDIA_CONTROLLER)
45 struct media_device *mdev;
46#endif
47 /* used to keep track of the registered subdevs */
48 struct list_head subdevs;
49 /* lock this struct; can be used by the driver as well if this
50 struct is embedded into a larger struct. */
51 spinlock_t lock;
52 /* unique device name, by default the driver name + bus ID */
53 char name[V4L2_DEVICE_NAME_SIZE];
54 /* notify callback called by some sub-devices. */
55 void (*notify)(struct v4l2_subdev *sd,
56 unsigned int notification, void *arg);
57 /* The control handler. May be NULL. */
58 struct v4l2_ctrl_handler *ctrl_handler;
59 /* Device's priority state */
60 struct v4l2_prio_state prio;
61 /* Keep track of the references to this struct. */
62 struct kref ref;
63 /* Release function that is called when the ref count goes to 0. */
64 void (*release)(struct v4l2_device *v4l2_dev);
65};
66
67static inline void v4l2_device_get(struct v4l2_device *v4l2_dev)
68{
69 kref_get(&v4l2_dev->ref);
70}
71
72int v4l2_device_put(struct v4l2_device *v4l2_dev);
73
74/* Initialize v4l2_dev and make dev->driver_data point to v4l2_dev.
75 dev may be NULL in rare cases (ISA devices). In that case you
76 must fill in the v4l2_dev->name field before calling this function. */
77int __must_check v4l2_device_register(struct device *dev, struct v4l2_device *v4l2_dev);
78
79/* Optional function to initialize the name field of struct v4l2_device using
80 the driver name and a driver-global atomic_t instance.
81 This function will increment the instance counter and returns the instance
82 value used in the name.
83
84 Example:
85
86 static atomic_t drv_instance = ATOMIC_INIT(0);
87
88 ...
89
90 instance = v4l2_device_set_name(&v4l2_dev, "foo", &drv_instance);
91
92 The first time this is called the name field will be set to foo0 and
93 this function returns 0. If the name ends with a digit (e.g. cx18),
94 then the name will be set to cx18-0 since cx180 looks really odd. */
95int v4l2_device_set_name(struct v4l2_device *v4l2_dev, const char *basename,
96 atomic_t *instance);
97
98/* Set v4l2_dev->dev to NULL. Call when the USB parent disconnects.
99 Since the parent disappears this ensures that v4l2_dev doesn't have an
100 invalid parent pointer. */
101void v4l2_device_disconnect(struct v4l2_device *v4l2_dev);
102
103/* Unregister all sub-devices and any other resources related to v4l2_dev. */
104void v4l2_device_unregister(struct v4l2_device *v4l2_dev);
105
106/* Register a subdev with a v4l2 device. While registered the subdev module
107 is marked as in-use. An error is returned if the module is no longer
108 loaded when you attempt to register it. */
109int __must_check v4l2_device_register_subdev(struct v4l2_device *v4l2_dev,
110 struct v4l2_subdev *sd);
111/* Unregister a subdev with a v4l2 device. Can also be called if the subdev
112 wasn't registered. In that case it will do nothing. */
113void v4l2_device_unregister_subdev(struct v4l2_subdev *sd);
114
115/* Register device nodes for all subdev of the v4l2 device that are marked with
116 * the V4L2_SUBDEV_FL_HAS_DEVNODE flag.
117 */
118int __must_check
119v4l2_device_register_subdev_nodes(struct v4l2_device *v4l2_dev);
120
121/* Send a notification to v4l2_device. */
122static inline void v4l2_subdev_notify(struct v4l2_subdev *sd,
123 unsigned int notification, void *arg)
124{
125 if (sd && sd->v4l2_dev && sd->v4l2_dev->notify)
126 sd->v4l2_dev->notify(sd, notification, arg);
127}
128
129/* Iterate over all subdevs. */
130#define v4l2_device_for_each_subdev(sd, v4l2_dev) \
131 list_for_each_entry(sd, &(v4l2_dev)->subdevs, list)
132
133/* Call the specified callback for all subdevs matching the condition.
134 Ignore any errors. Note that you cannot add or delete a subdev
135 while walking the subdevs list. */
136#define __v4l2_device_call_subdevs_p(v4l2_dev, sd, cond, o, f, args...) \
137 do { \
138 list_for_each_entry((sd), &(v4l2_dev)->subdevs, list) \
139 if ((cond) && (sd)->ops->o && (sd)->ops->o->f) \
140 (sd)->ops->o->f((sd) , ##args); \
141 } while (0)
142
143#define __v4l2_device_call_subdevs(v4l2_dev, cond, o, f, args...) \
144 do { \
145 struct v4l2_subdev *__sd; \
146 \
147 __v4l2_device_call_subdevs_p(v4l2_dev, __sd, cond, o, \
148 f , ##args); \
149 } while (0)
150
151/* Call the specified callback for all subdevs matching the condition.
152 If the callback returns an error other than 0 or -ENOIOCTLCMD, then
153 return with that error code. Note that you cannot add or delete a
154 subdev while walking the subdevs list. */
155#define __v4l2_device_call_subdevs_until_err_p(v4l2_dev, sd, cond, o, f, args...) \
156({ \
157 long __err = 0; \
158 \
159 list_for_each_entry((sd), &(v4l2_dev)->subdevs, list) { \
160 if ((cond) && (sd)->ops->o && (sd)->ops->o->f) \
161 __err = (sd)->ops->o->f((sd) , ##args); \
162 if (__err && __err != -ENOIOCTLCMD) \
163 break; \
164 } \
165 (__err == -ENOIOCTLCMD) ? 0 : __err; \
166})
167
168#define __v4l2_device_call_subdevs_until_err(v4l2_dev, cond, o, f, args...) \
169({ \
170 struct v4l2_subdev *__sd; \
171 __v4l2_device_call_subdevs_until_err_p(v4l2_dev, __sd, cond, o, \
172 f , ##args); \
173})
174
175/* Call the specified callback for all subdevs matching grp_id (if 0, then
176 match them all). Ignore any errors. Note that you cannot add or delete
177 a subdev while walking the subdevs list. */
178#define v4l2_device_call_all(v4l2_dev, grpid, o, f, args...) \
179 do { \
180 struct v4l2_subdev *__sd; \
181 \
182 __v4l2_device_call_subdevs_p(v4l2_dev, __sd, \
183 !(grpid) || __sd->grp_id == (grpid), o, f , \
184 ##args); \
185 } while (0)
186
187/* Call the specified callback for all subdevs matching grp_id (if 0, then
188 match them all). If the callback returns an error other than 0 or
189 -ENOIOCTLCMD, then return with that error code. Note that you cannot
190 add or delete a subdev while walking the subdevs list. */
191#define v4l2_device_call_until_err(v4l2_dev, grpid, o, f, args...) \
192({ \
193 struct v4l2_subdev *__sd; \
194 __v4l2_device_call_subdevs_until_err_p(v4l2_dev, __sd, \
195 !(grpid) || __sd->grp_id == (grpid), o, f , \
196 ##args); \
197})
198
199#define v4l2_device_has_op(v4l2_dev, o, f) \
200({ \
201 struct v4l2_subdev *__sd; \
202 bool __result = false; \
203 list_for_each_entry(__sd, &(v4l2_dev)->subdevs, list) { \
204 if (v4l2_subdev_has_op(__sd, o, f)) { \
205 __result = true; \
206 break; \
207 } \
208 } \
209 __result; \
210})
211
212#endif
1/*
2 V4L2 device support header.
3
4 Copyright (C) 2008 Hans Verkuil <hverkuil@xs4all.nl>
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 as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
10
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.
15
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software
18 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 */
20
21#ifndef _V4L2_DEVICE_H
22#define _V4L2_DEVICE_H
23
24#include <media/media-device.h>
25#include <media/v4l2-subdev.h>
26#include <media/v4l2-dev.h>
27
28/* Each instance of a V4L2 device should create the v4l2_device struct,
29 either stand-alone or embedded in a larger struct.
30
31 It allows easy access to sub-devices (see v4l2-subdev.h) and provides
32 basic V4L2 device-level support.
33 */
34
35#define V4L2_DEVICE_NAME_SIZE (20 + 16)
36
37struct v4l2_ctrl_handler;
38
39struct v4l2_device {
40 /* dev->driver_data points to this struct.
41 Note: dev might be NULL if there is no parent device
42 as is the case with e.g. ISA devices. */
43 struct device *dev;
44#if defined(CONFIG_MEDIA_CONTROLLER)
45 struct media_device *mdev;
46#endif
47 /* used to keep track of the registered subdevs */
48 struct list_head subdevs;
49 /* lock this struct; can be used by the driver as well if this
50 struct is embedded into a larger struct. */
51 spinlock_t lock;
52 /* unique device name, by default the driver name + bus ID */
53 char name[V4L2_DEVICE_NAME_SIZE];
54 /* notify callback called by some sub-devices. */
55 void (*notify)(struct v4l2_subdev *sd,
56 unsigned int notification, void *arg);
57 /* The control handler. May be NULL. */
58 struct v4l2_ctrl_handler *ctrl_handler;
59 /* Device's priority state */
60 struct v4l2_prio_state prio;
61 /* BKL replacement mutex. Temporary solution only. */
62 struct mutex ioctl_lock;
63 /* Keep track of the references to this struct. */
64 struct kref ref;
65 /* Release function that is called when the ref count goes to 0. */
66 void (*release)(struct v4l2_device *v4l2_dev);
67};
68
69static inline void v4l2_device_get(struct v4l2_device *v4l2_dev)
70{
71 kref_get(&v4l2_dev->ref);
72}
73
74int v4l2_device_put(struct v4l2_device *v4l2_dev);
75
76/* Initialize v4l2_dev and make dev->driver_data point to v4l2_dev.
77 dev may be NULL in rare cases (ISA devices). In that case you
78 must fill in the v4l2_dev->name field before calling this function. */
79int __must_check v4l2_device_register(struct device *dev, struct v4l2_device *v4l2_dev);
80
81/* Optional function to initialize the name field of struct v4l2_device using
82 the driver name and a driver-global atomic_t instance.
83 This function will increment the instance counter and returns the instance
84 value used in the name.
85
86 Example:
87
88 static atomic_t drv_instance = ATOMIC_INIT(0);
89
90 ...
91
92 instance = v4l2_device_set_name(&v4l2_dev, "foo", &drv_instance);
93
94 The first time this is called the name field will be set to foo0 and
95 this function returns 0. If the name ends with a digit (e.g. cx18),
96 then the name will be set to cx18-0 since cx180 looks really odd. */
97int v4l2_device_set_name(struct v4l2_device *v4l2_dev, const char *basename,
98 atomic_t *instance);
99
100/* Set v4l2_dev->dev to NULL. Call when the USB parent disconnects.
101 Since the parent disappears this ensures that v4l2_dev doesn't have an
102 invalid parent pointer. */
103void v4l2_device_disconnect(struct v4l2_device *v4l2_dev);
104
105/* Unregister all sub-devices and any other resources related to v4l2_dev. */
106void v4l2_device_unregister(struct v4l2_device *v4l2_dev);
107
108/* Register a subdev with a v4l2 device. While registered the subdev module
109 is marked as in-use. An error is returned if the module is no longer
110 loaded when you attempt to register it. */
111int __must_check v4l2_device_register_subdev(struct v4l2_device *v4l2_dev,
112 struct v4l2_subdev *sd);
113/* Unregister a subdev with a v4l2 device. Can also be called if the subdev
114 wasn't registered. In that case it will do nothing. */
115void v4l2_device_unregister_subdev(struct v4l2_subdev *sd);
116
117/* Register device nodes for all subdev of the v4l2 device that are marked with
118 * the V4L2_SUBDEV_FL_HAS_DEVNODE flag.
119 */
120int __must_check
121v4l2_device_register_subdev_nodes(struct v4l2_device *v4l2_dev);
122
123/* Iterate over all subdevs. */
124#define v4l2_device_for_each_subdev(sd, v4l2_dev) \
125 list_for_each_entry(sd, &(v4l2_dev)->subdevs, list)
126
127/* Call the specified callback for all subdevs matching the condition.
128 Ignore any errors. Note that you cannot add or delete a subdev
129 while walking the subdevs list. */
130#define __v4l2_device_call_subdevs_p(v4l2_dev, sd, cond, o, f, args...) \
131 do { \
132 list_for_each_entry((sd), &(v4l2_dev)->subdevs, list) \
133 if ((cond) && (sd)->ops->o && (sd)->ops->o->f) \
134 (sd)->ops->o->f((sd) , ##args); \
135 } while (0)
136
137#define __v4l2_device_call_subdevs(v4l2_dev, cond, o, f, args...) \
138 do { \
139 struct v4l2_subdev *__sd; \
140 \
141 __v4l2_device_call_subdevs_p(v4l2_dev, __sd, cond, o, \
142 f , ##args); \
143 } while (0)
144
145/* Call the specified callback for all subdevs matching the condition.
146 If the callback returns an error other than 0 or -ENOIOCTLCMD, then
147 return with that error code. Note that you cannot add or delete a
148 subdev while walking the subdevs list. */
149#define __v4l2_device_call_subdevs_until_err_p(v4l2_dev, sd, cond, o, f, args...) \
150({ \
151 long __err = 0; \
152 \
153 list_for_each_entry((sd), &(v4l2_dev)->subdevs, list) { \
154 if ((cond) && (sd)->ops->o && (sd)->ops->o->f) \
155 __err = (sd)->ops->o->f((sd) , ##args); \
156 if (__err && __err != -ENOIOCTLCMD) \
157 break; \
158 } \
159 (__err == -ENOIOCTLCMD) ? 0 : __err; \
160})
161
162#define __v4l2_device_call_subdevs_until_err(v4l2_dev, cond, o, f, args...) \
163({ \
164 struct v4l2_subdev *__sd; \
165 __v4l2_device_call_subdevs_until_err_p(v4l2_dev, __sd, cond, o, \
166 f , ##args); \
167})
168
169/* Call the specified callback for all subdevs matching grp_id (if 0, then
170 match them all). Ignore any errors. Note that you cannot add or delete
171 a subdev while walking the subdevs list. */
172#define v4l2_device_call_all(v4l2_dev, grpid, o, f, args...) \
173 do { \
174 struct v4l2_subdev *__sd; \
175 \
176 __v4l2_device_call_subdevs_p(v4l2_dev, __sd, \
177 !(grpid) || __sd->grp_id == (grpid), o, f , \
178 ##args); \
179 } while (0)
180
181/* Call the specified callback for all subdevs matching grp_id (if 0, then
182 match them all). If the callback returns an error other than 0 or
183 -ENOIOCTLCMD, then return with that error code. Note that you cannot
184 add or delete a subdev while walking the subdevs list. */
185#define v4l2_device_call_until_err(v4l2_dev, grpid, o, f, args...) \
186({ \
187 struct v4l2_subdev *__sd; \
188 __v4l2_device_call_subdevs_until_err_p(v4l2_dev, __sd, \
189 !(grpid) || __sd->grp_id == (grpid), o, f , \
190 ##args); \
191})
192
193#endif