summaryrefslogtreecommitdiffstats
path: root/drivers/media/i2c/tda9840.c
blob: 3f1266246ca3ed4536a24e06df32d9e751eb5f73 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
 /*
    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/slab.h>
#include <linux/i2c.h>
#include <media/v4l2-device.h>
#include <media/v4l2-chip-ident.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_status(struct v4l2_subdev *sd)
{
	struct i2c_client *client = v4l2_get_subdevdata(sd);
	u8 byte;

	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);
	return byte & 0x60;
}

static int tda9840_s_tuner(struct v4l2_subdev *sd, const struct v4l2_tuner *t)
{
	int stat = tda9840_status(sd);
	int byte;

	if (t->index)
		return -EINVAL;

	stat = stat < 0 ? 0 : stat;
	if (stat == 0 || stat == 0x60) /* mono input */
		byte = TDA9840_SET_MONO;
	else if (stat == 0x40) /* stereo input */
		byte = (t->audmode == V4L2_TUNER_MODE_MONO) ?
			TDA9840_SET_MONO : TDA9840_SET_STEREO;
	else { /* bilingual */
		switch (t->audmode) {
		case V4L2_TUNER_MODE_LANG1_LANG2:
			byte = TDA9840_SET_BOTH;
			break;
		case V4L2_TUNER_MODE_LANG2:
			byte = TDA9840_SET_LANG2;
			break;
		default:
			byte = TDA9840_SET_LANG1;
			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)
{
	int stat = tda9840_status(sd);

	if (stat < 0)
		return stat;

	t->rxsubchans = V4L2_TUNER_SUB_MONO;

	switch (stat & 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 = devm_kzalloc(&client->dev, sizeof(*sd), 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);
	return 0;
}

static const struct i2c_device_id tda9840_id[] = {
	{ "tda9840", 0 },
	{ }
};
MODULE_DEVICE_TABLE(i2c, tda9840_id);

static struct i2c_driver tda9840_driver = {
	.driver = {
		.owner	= THIS_MODULE,
		.name	= "tda9840",
	},
	.probe		= tda9840_probe,
	.remove		= tda9840_remove,
	.id_table	= tda9840_id,
};

module_i2c_driver(tda9840_driver);