tda9840.c
/*
tda9840 - i2c-driver for the tda9840 by SGS Thomson
Copyright (C) 1998-2003 Michael Hunold <michael@mihu.de>
Copyright (C) 2008 Hans Verkuil <hverkuil@xs4all.nl>
The tda9840 is a stereo/dual sound processor with digital
identification. It can be found at address 0x84 on the i2c-bus.
For detailed informations download the specifications directly
from SGS Thomson at http://www.st.com
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <linux/module.h>
#include <linux/ioctl.h>
#include <linux/i2c.h>
#include <media/v4l2-device.h>
#include <media/v4l2-chip-ident.h>
#include <media/v4l2-i2c-drv.h>
MODULE_AUTHOR("Michael Hunold <michael@mihu.de>");
MODULE_DESCRIPTION("tda9840 driver");
MODULE_LICENSE("GPL");
static int debug;
module_param(debug, int, 0644);
MODULE_PARM_DESC(debug, "Debug level (0-1)");
#define SWITCH 0x00
#define LEVEL_ADJUST 0x02
#define STEREO_ADJUST 0x03
#define TEST 0x04
#define TDA9840_SET_MUTE 0x00
#define TDA9840_SET_MONO 0x10
#define TDA9840_SET_STEREO 0x2a
#define TDA9840_SET_LANG1 0x12
#define TDA9840_SET_LANG2 0x1e
#define TDA9840_SET_BOTH 0x1a
#define TDA9840_SET_BOTH_R 0x16
#define TDA9840_SET_EXTERNAL 0x7a
static void tda9840_write(struct v4l2_subdev *sd, u8 reg, u8 val)
{
struct i2c_client *client = v4l2_get_subdevdata(sd);
if (i2c_smbus_write_byte_data(client, reg, val))
v4l2_dbg(1, debug, sd, "error writing %02x to %02x\n",
val, reg);
}
static int tda9840_s_tuner(struct v4l2_subdev *sd, struct v4l2_tuner *t)
{
int byte;
if (t->index)
return -EINVAL;
switch (t->audmode) {
case V4L2_TUNER_MODE_STEREO:
byte = TDA9840_SET_STEREO;
break;
case V4L2_TUNER_MODE_LANG1_LANG2:
byte = TDA9840_SET_BOTH;
break;
case V4L2_TUNER_MODE_LANG1:
byte = TDA9840_SET_LANG1;
break;
case V4L2_TUNER_MODE_LANG2:
byte = TDA9840_SET_LANG2;
break;
default:
byte = TDA9840_SET_MONO;
break;
}
v4l2_dbg(1, debug, sd, "TDA9840_SWITCH: 0x%02x\n", byte);
tda9840_write(sd, SWITCH, byte);
return 0;
}
static int tda9840_g_tuner(struct v4l2_subdev *sd, struct v4l2_tuner *t)
{
struct i2c_client *client = v4l2_get_subdevdata(sd);
u8 byte;
t->rxsubchans = V4L2_TUNER_SUB_MONO;
if (1 != i2c_master_recv(client, &byte, 1)) {
v4l2_dbg(1, debug, sd,
"i2c_master_recv() failed\n");
return -EIO;
}
if (byte & 0x80) {
v4l2_dbg(1, debug, sd,
"TDA9840_DETECT: register contents invalid\n");
return -EINVAL;
}
v4l2_dbg(1, debug, sd, "TDA9840_DETECT: byte: 0x%02x\n", byte);
switch (byte & 0x60) {
case 0x00:
t->rxsubchans = V4L2_TUNER_SUB_MONO;
break;
case 0x20:
t->rxsubchans = V4L2_TUNER_SUB_LANG1 | V4L2_TUNER_SUB_LANG2;
break;
case 0x40:
t->rxsubchans = V4L2_TUNER_SUB_STEREO | V4L2_TUNER_SUB_MONO;
break;
default: /* Incorrect detect */
t->rxsubchans = V4L2_TUNER_MODE_MONO;
break;
}
return 0;
}
static int tda9840_g_chip_ident(struct v4l2_subdev *sd, struct v4l2_dbg_chip_ident *chip)
{
struct i2c_client *client = v4l2_get_subdevdata(sd);
return v4l2_chip_ident_i2c_client(client, chip, V4L2_IDENT_TDA9840, 0);
}
/* ----------------------------------------------------------------------- */
static const struct v4l2_subdev_core_ops tda9840_core_ops = {
.g_chip_ident = tda9840_g_chip_ident,
};
static const struct v4l2_subdev_tuner_ops tda9840_tuner_ops = {
.s_tuner = tda9840_s_tuner,
.g_tuner = tda9840_g_tuner,
};
static const struct v4l2_subdev_ops tda9840_ops = {
.core = &tda9840_core_ops,
.tuner = &tda9840_tuner_ops,
};
/* ----------------------------------------------------------------------- */
static int tda9840_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct v4l2_subdev *sd;
/* let's see whether this adapter can support what we need */
if (!i2c_check_functionality(client->adapter,
I2C_FUNC_SMBUS_READ_BYTE_DATA |
I2C_FUNC_SMBUS_WRITE_BYTE_DATA))
return -EIO;
v4l_info(client, "chip found @ 0x%x (%s)\n",
client->addr << 1, client->adapter->name);
sd = kmalloc(sizeof(struct v4l2_subdev), GFP_KERNEL);
if (sd == NULL)
return -ENOMEM;
v4l2_i2c_subdev_init(sd, client, &tda9840_ops);
/* set initial values for level & stereo - adjustment, mode */
tda9840_write(sd, LEVEL_ADJUST, 0);
tda9840_write(sd, STEREO_ADJUST, 0);
tda9840_write(sd, SWITCH, TDA9840_SET_STEREO);
return 0;
}
static int tda9840_remove(struct i2c_client *client)
{
struct v4l2_subdev *sd = i2c_get_clientdata(client);
v4l2_device_unregister_subdev(sd);
kfree(sd);
return 0;
}
static const struct i2c_device_id tda9840_id[] = {
{ "tda9840", 0 },
{ }
};
MODULE_DEVICE_TABLE(i2c, tda9840_id);
static struct v4l2_i2c_driver_data v4l2_i2c_data = {
.name = "tda9840",
.probe = tda9840_probe,
.remove = tda9840_remove,
.id_table = tda9840_id,
};