V4L/DVB (11365): tvaudio: remove i2c legacy code
[linux-2.6.git] / include / media / v4l2-i2c-drv-legacy.h
1 /*
2  * v4l2-i2c-drv-legacy.h - contains I2C handling code that's identical
3  *                  for all V4L2 I2C drivers. Use this header if the
4  *                  I2C driver is used by both legacy drivers and
5  *                  drivers converted to the bus-based I2C API.
6  *
7  * Copyright (C) 2007 Hans Verkuil <hverkuil@xs4all.nl>
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License as published by
11  * the Free Software Foundation; either version 2 of the License, or
12  * (at your option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17  * GNU General Public License for more details.
18  *
19  * You should have received a copy of the GNU General Public License
20  * along with this program; if not, write to the Free Software
21  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
22  */
23
24 /* NOTE: the full version of this header is in the v4l-dvb repository
25  * and allows v4l i2c drivers to be compiled on older kernels as well.
26  * The version of this header as it appears in the kernel is a stripped
27  * version (without all the backwards compatibility stuff) and so it
28  * looks a bit odd.
29  *
30  * If you look at the full version then you will understand the reason
31  * for introducing this header since you really don't want to have all
32  * the tricky backwards compatibility code in each and every i2c driver.
33  */
34
35 struct v4l2_i2c_driver_data {
36         const char * const name;
37         int driverid;
38         int (*command)(struct i2c_client *client, unsigned int cmd, void *arg);
39         int (*probe)(struct i2c_client *client, const struct i2c_device_id *id);
40         int (*remove)(struct i2c_client *client);
41         int (*suspend)(struct i2c_client *client, pm_message_t state);
42         int (*resume)(struct i2c_client *client);
43         int (*legacy_probe)(struct i2c_adapter *adapter);
44         int legacy_class;
45         const struct i2c_device_id *id_table;
46 };
47
48 static struct v4l2_i2c_driver_data v4l2_i2c_data;
49 static const struct i2c_client_address_data addr_data;
50 static struct i2c_driver v4l2_i2c_driver_legacy;
51 static char v4l2_i2c_drv_name_legacy[32];
52
53 static int v4l2_i2c_drv_attach_legacy(struct i2c_adapter *adapter, int address, int kind)
54 {
55         return v4l2_i2c_attach(adapter, address, &v4l2_i2c_driver_legacy,
56                         v4l2_i2c_drv_name_legacy, v4l2_i2c_data.probe);
57 }
58
59 static int v4l2_i2c_drv_probe_legacy(struct i2c_adapter *adapter)
60 {
61         if (v4l2_i2c_data.legacy_probe) {
62                 if (v4l2_i2c_data.legacy_probe(adapter))
63                         return i2c_probe(adapter, &addr_data, v4l2_i2c_drv_attach_legacy);
64                 return 0;
65         }
66         if (adapter->class & v4l2_i2c_data.legacy_class)
67                 return i2c_probe(adapter, &addr_data, v4l2_i2c_drv_attach_legacy);
68         return 0;
69 }
70
71 static int v4l2_i2c_drv_detach_legacy(struct i2c_client *client)
72 {
73         int err;
74
75         if (v4l2_i2c_data.remove)
76                 v4l2_i2c_data.remove(client);
77
78         err = i2c_detach_client(client);
79         if (err)
80                 return err;
81         kfree(client);
82         return 0;
83 }
84
85 static int v4l2_i2c_drv_suspend_helper(struct i2c_client *client, pm_message_t state)
86 {
87         return v4l2_i2c_data.suspend ? v4l2_i2c_data.suspend(client, state) : 0;
88 }
89
90 static int v4l2_i2c_drv_resume_helper(struct i2c_client *client)
91 {
92         return v4l2_i2c_data.resume ? v4l2_i2c_data.resume(client) : 0;
93 }
94
95 /* ----------------------------------------------------------------------- */
96
97 /* i2c implementation */
98 static struct i2c_driver v4l2_i2c_driver_legacy = {
99         .driver = {
100                 .owner = THIS_MODULE,
101         },
102         .attach_adapter = v4l2_i2c_drv_probe_legacy,
103         .detach_client = v4l2_i2c_drv_detach_legacy,
104         .suspend = v4l2_i2c_drv_suspend_helper,
105         .resume  = v4l2_i2c_drv_resume_helper,
106 };
107
108 /* ----------------------------------------------------------------------- */
109
110 /* i2c implementation */
111 static struct i2c_driver v4l2_i2c_driver = {
112         .suspend        = v4l2_i2c_drv_suspend_helper,
113         .resume         = v4l2_i2c_drv_resume_helper,
114 };
115
116 static int __init v4l2_i2c_drv_init(void)
117 {
118         int err;
119
120         strlcpy(v4l2_i2c_drv_name_legacy, v4l2_i2c_data.name, sizeof(v4l2_i2c_drv_name_legacy));
121         strlcat(v4l2_i2c_drv_name_legacy, "'", sizeof(v4l2_i2c_drv_name_legacy));
122
123         if (v4l2_i2c_data.legacy_class == 0)
124                 v4l2_i2c_data.legacy_class = I2C_CLASS_TV_ANALOG;
125
126         v4l2_i2c_driver_legacy.driver.name = v4l2_i2c_drv_name_legacy;
127         v4l2_i2c_driver_legacy.id = v4l2_i2c_data.driverid;
128         v4l2_i2c_driver_legacy.command = v4l2_i2c_data.command;
129         err = i2c_add_driver(&v4l2_i2c_driver_legacy);
130
131         if (err)
132                 return err;
133         v4l2_i2c_driver.driver.name = v4l2_i2c_data.name;
134         v4l2_i2c_driver.id = v4l2_i2c_data.driverid;
135         v4l2_i2c_driver.command = v4l2_i2c_data.command;
136         v4l2_i2c_driver.probe = v4l2_i2c_data.probe;
137         v4l2_i2c_driver.remove = v4l2_i2c_data.remove;
138         v4l2_i2c_driver.id_table = v4l2_i2c_data.id_table;
139         err = i2c_add_driver(&v4l2_i2c_driver);
140         if (err)
141                 i2c_del_driver(&v4l2_i2c_driver_legacy);
142         return err;
143 }
144
145 static void __exit v4l2_i2c_drv_cleanup(void)
146 {
147         i2c_del_driver(&v4l2_i2c_driver_legacy);
148         i2c_del_driver(&v4l2_i2c_driver);
149 }
150
151 module_init(v4l2_i2c_drv_init);
152 module_exit(v4l2_i2c_drv_cleanup);