2 tea6420 - i2c-driver for the tea6420 by SGS Thomson
4 Copyright (C) 1998-2003 Michael Hunold <michael@mihu.de>
5 Copyright (C) 2008 Hans Verkuil <hverkuil@xs4all.nl>
7 The tea6420 is a bus controlled audio-matrix with 5 stereo inputs,
8 4 stereo outputs and gain control for each output.
9 It is cascadable, i.e. it can be found at the addresses 0x98
10 and 0x9a on the i2c-bus.
12 For detailed informations download the specifications directly
13 from SGS Thomson at http://www.st.com
15 This program is free software; you can redistribute it and/or modify
16 it under the terms of the GNU General Public License as published by
17 the Free Software Foundation; either version 2 of the License, or
18 (at your option) any later version.
20 This program is distributed in the hope that it will be useful,
21 but WITHOUT ANY WARRANTY; without even the implied warranty of
22 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
23 GNU General Public License for more details.
25 You should have received a copy of the GNU General Public License
26 along with this program; if not, write to the Free Software
27 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
31 #include <linux/module.h>
32 #include <linux/ioctl.h>
33 #include <linux/slab.h>
34 #include <linux/i2c.h>
35 #include <media/v4l2-device.h>
36 #include <media/v4l2-chip-ident.h>
39 MODULE_AUTHOR("Michael Hunold <michael@mihu.de>");
40 MODULE_DESCRIPTION("tea6420 driver");
41 MODULE_LICENSE("GPL");
44 module_param(debug
, int, 0644);
46 MODULE_PARM_DESC(debug
, "Debug level (0-1)");
49 /* make a connection between the input 'i' and the output 'o'
50 with gain 'g' (note: i = 6 means 'mute') */
51 static int tea6420_s_routing(struct v4l2_subdev
*sd
,
52 u32 i
, u32 o
, u32 config
)
54 struct i2c_client
*client
= v4l2_get_subdevdata(sd
);
55 int g
= (o
>> 4) & 0xf;
60 v4l2_dbg(1, debug
, sd
, "i=%d, o=%d, g=%d\n", i
, o
, g
);
62 /* check if the parameters are valid */
63 if (i
< 1 || i
> 6 || o
< 1 || o
> 4 || g
< 0 || g
> 6 || g
% 2 != 0)
66 byte
= ((o
- 1) << 5);
69 /* to understand this, have a look at the tea6420-specs (p.5) */
84 ret
= i2c_smbus_write_byte(client
, byte
);
86 v4l2_dbg(1, debug
, sd
,
87 "i2c_smbus_write_byte() failed, ret:%d\n", ret
);
93 static int tea6420_g_chip_ident(struct v4l2_subdev
*sd
, struct v4l2_dbg_chip_ident
*chip
)
95 struct i2c_client
*client
= v4l2_get_subdevdata(sd
);
97 return v4l2_chip_ident_i2c_client(client
, chip
, V4L2_IDENT_TEA6420
, 0);
100 /* ----------------------------------------------------------------------- */
102 static const struct v4l2_subdev_core_ops tea6420_core_ops
= {
103 .g_chip_ident
= tea6420_g_chip_ident
,
106 static const struct v4l2_subdev_audio_ops tea6420_audio_ops
= {
107 .s_routing
= tea6420_s_routing
,
110 static const struct v4l2_subdev_ops tea6420_ops
= {
111 .core
= &tea6420_core_ops
,
112 .audio
= &tea6420_audio_ops
,
115 static int tea6420_probe(struct i2c_client
*client
,
116 const struct i2c_device_id
*id
)
118 struct v4l2_subdev
*sd
;
121 /* let's see whether this adapter can support what we need */
122 if (!i2c_check_functionality(client
->adapter
, I2C_FUNC_SMBUS_WRITE_BYTE
))
125 v4l_info(client
, "chip found @ 0x%x (%s)\n",
126 client
->addr
<< 1, client
->adapter
->name
);
128 sd
= kmalloc(sizeof(struct v4l2_subdev
), GFP_KERNEL
);
131 v4l2_i2c_subdev_init(sd
, client
, &tea6420_ops
);
133 /* set initial values: set "mute"-input to all outputs at gain 0 */
135 for (i
= 1; i
< 5; i
++)
136 err
+= tea6420_s_routing(sd
, 6, i
, 0);
138 v4l_dbg(1, debug
, client
, "could not initialize tea6420\n");
144 static int tea6420_remove(struct i2c_client
*client
)
146 struct v4l2_subdev
*sd
= i2c_get_clientdata(client
);
148 v4l2_device_unregister_subdev(sd
);
153 static const struct i2c_device_id tea6420_id
[] = {
157 MODULE_DEVICE_TABLE(i2c
, tea6420_id
);
159 static struct i2c_driver tea6420_driver
= {
161 .owner
= THIS_MODULE
,
164 .probe
= tea6420_probe
,
165 .remove
= tea6420_remove
,
166 .id_table
= tea6420_id
,
169 static __init
int init_tea6420(void)
171 return i2c_add_driver(&tea6420_driver
);
174 static __exit
void exit_tea6420(void)
176 i2c_del_driver(&tea6420_driver
);
179 module_init(init_tea6420
);
180 module_exit(exit_tea6420
);