1 /*
2    tda9840 - i2c-driver for the tda9840 by SGS Thomson
3
4    Copyright (C) 1998-2003 Michael Hunold <michael@mihu.de>
5    Copyright (C) 2008 Hans Verkuil <hverkuil@xs4all.nl>
6
7    The tda9840 is a stereo/dual sound processor with digital
8    identification. It can be found at address 0x84 on the i2c-bus.
9
10    For detailed informations download the specifications directly
11    from SGS Thomson at http://www.st.com
12
13    This program is free software; you can redistribute it and/or modify
14    it under the terms of the GNU General Public License as published by
15    the Free Software Foundation; either version 2 of the License, or
16    (at your option) any later version.
17
18    This program is distributed in the hope that it will be useful,
19    but WITHOUT ANY WARRANTY; without even the implied warranty of
20    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
21    GNU General Public License for more details.
22
23    You should have received a copy of the GNU General Public License
24    along with this program; if not, write to the Free Software
25    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
26  */
27
28
29#include <linux/module.h>
30#include <linux/ioctl.h>
31#include <linux/slab.h>
32#include <linux/i2c.h>
33#include <media/v4l2-device.h>
34
35MODULE_AUTHOR("Michael Hunold <michael@mihu.de>");
36MODULE_DESCRIPTION("tda9840 driver");
37MODULE_LICENSE("GPL");
38
39static int debug;
40module_param(debug, int, 0644);
41
42MODULE_PARM_DESC(debug, "Debug level (0-1)");
43
44#define	SWITCH		0x00
45#define	LEVEL_ADJUST	0x02
46#define	STEREO_ADJUST	0x03
47#define	TEST		0x04
48
49#define TDA9840_SET_MUTE                0x00
50#define TDA9840_SET_MONO                0x10
51#define TDA9840_SET_STEREO              0x2a
52#define TDA9840_SET_LANG1               0x12
53#define TDA9840_SET_LANG2               0x1e
54#define TDA9840_SET_BOTH                0x1a
55#define TDA9840_SET_BOTH_R              0x16
56#define TDA9840_SET_EXTERNAL            0x7a
57
58
59static void tda9840_write(struct v4l2_subdev *sd, u8 reg, u8 val)
60{
61	struct i2c_client *client = v4l2_get_subdevdata(sd);
62
63	if (i2c_smbus_write_byte_data(client, reg, val))
64		v4l2_dbg(1, debug, sd, "error writing %02x to %02x\n",
65				val, reg);
66}
67
68static int tda9840_status(struct v4l2_subdev *sd)
69{
70	struct i2c_client *client = v4l2_get_subdevdata(sd);
71	u8 byte;
72
73	if (1 != i2c_master_recv(client, &byte, 1)) {
74		v4l2_dbg(1, debug, sd,
75			"i2c_master_recv() failed\n");
76		return -EIO;
77	}
78
79	if (byte & 0x80) {
80		v4l2_dbg(1, debug, sd,
81			"TDA9840_DETECT: register contents invalid\n");
82		return -EINVAL;
83	}
84
85	v4l2_dbg(1, debug, sd, "TDA9840_DETECT: byte: 0x%02x\n", byte);
86	return byte & 0x60;
87}
88
89static int tda9840_s_tuner(struct v4l2_subdev *sd, const struct v4l2_tuner *t)
90{
91	int stat = tda9840_status(sd);
92	int byte;
93
94	if (t->index)
95		return -EINVAL;
96
97	stat = stat < 0 ? 0 : stat;
98	if (stat == 0 || stat == 0x60) /* mono input */
99		byte = TDA9840_SET_MONO;
100	else if (stat == 0x40) /* stereo input */
101		byte = (t->audmode == V4L2_TUNER_MODE_MONO) ?
102			TDA9840_SET_MONO : TDA9840_SET_STEREO;
103	else { /* bilingual */
104		switch (t->audmode) {
105		case V4L2_TUNER_MODE_LANG1_LANG2:
106			byte = TDA9840_SET_BOTH;
107			break;
108		case V4L2_TUNER_MODE_LANG2:
109			byte = TDA9840_SET_LANG2;
110			break;
111		default:
112			byte = TDA9840_SET_LANG1;
113			break;
114		}
115	}
116	v4l2_dbg(1, debug, sd, "TDA9840_SWITCH: 0x%02x\n", byte);
117	tda9840_write(sd, SWITCH, byte);
118	return 0;
119}
120
121static int tda9840_g_tuner(struct v4l2_subdev *sd, struct v4l2_tuner *t)
122{
123	int stat = tda9840_status(sd);
124
125	if (stat < 0)
126		return stat;
127
128	t->rxsubchans = V4L2_TUNER_SUB_MONO;
129
130	switch (stat & 0x60) {
131	case 0x00:
132		t->rxsubchans = V4L2_TUNER_SUB_MONO;
133		break;
134	case 0x20:
135		t->rxsubchans = V4L2_TUNER_SUB_LANG1 | V4L2_TUNER_SUB_LANG2;
136		break;
137	case 0x40:
138		t->rxsubchans = V4L2_TUNER_SUB_STEREO | V4L2_TUNER_SUB_MONO;
139		break;
140	default: /* Incorrect detect */
141		t->rxsubchans = V4L2_TUNER_MODE_MONO;
142		break;
143	}
144	return 0;
145}
146
147/* ----------------------------------------------------------------------- */
148
149static const struct v4l2_subdev_tuner_ops tda9840_tuner_ops = {
150	.s_tuner = tda9840_s_tuner,
151	.g_tuner = tda9840_g_tuner,
152};
153
154static const struct v4l2_subdev_ops tda9840_ops = {
155	.tuner = &tda9840_tuner_ops,
156};
157
158/* ----------------------------------------------------------------------- */
159
160static int tda9840_probe(struct i2c_client *client,
161			  const struct i2c_device_id *id)
162{
163	struct v4l2_subdev *sd;
164
165	/* let's see whether this adapter can support what we need */
166	if (!i2c_check_functionality(client->adapter,
167			I2C_FUNC_SMBUS_READ_BYTE_DATA |
168			I2C_FUNC_SMBUS_WRITE_BYTE_DATA))
169		return -EIO;
170
171	v4l_info(client, "chip found @ 0x%x (%s)\n",
172			client->addr << 1, client->adapter->name);
173
174	sd = devm_kzalloc(&client->dev, sizeof(*sd), GFP_KERNEL);
175	if (sd == NULL)
176		return -ENOMEM;
177	v4l2_i2c_subdev_init(sd, client, &tda9840_ops);
178
179	/* set initial values for level & stereo - adjustment, mode */
180	tda9840_write(sd, LEVEL_ADJUST, 0);
181	tda9840_write(sd, STEREO_ADJUST, 0);
182	tda9840_write(sd, SWITCH, TDA9840_SET_STEREO);
183	return 0;
184}
185
186static int tda9840_remove(struct i2c_client *client)
187{
188	struct v4l2_subdev *sd = i2c_get_clientdata(client);
189
190	v4l2_device_unregister_subdev(sd);
191	return 0;
192}
193
194static const struct i2c_device_id tda9840_id[] = {
195	{ "tda9840", 0 },
196	{ }
197};
198MODULE_DEVICE_TABLE(i2c, tda9840_id);
199
200static struct i2c_driver tda9840_driver = {
201	.driver = {
202		.owner	= THIS_MODULE,
203		.name	= "tda9840",
204	},
205	.probe		= tda9840_probe,
206	.remove		= tda9840_remove,
207	.id_table	= tda9840_id,
208};
209
210module_i2c_driver(tda9840_driver);
211