xref: /openbmc/linux/drivers/media/i2c/tda9840.c (revision ebd09753)
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 
35 MODULE_AUTHOR("Michael Hunold <michael@mihu.de>");
36 MODULE_DESCRIPTION("tda9840 driver");
37 MODULE_LICENSE("GPL");
38 
39 static int debug;
40 module_param(debug, int, 0644);
41 
42 MODULE_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 
59 static 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 
68 static int tda9840_status(struct v4l2_subdev *sd)
69 {
70 	struct i2c_client *client = v4l2_get_subdevdata(sd);
71 	int rc;
72 	u8 byte;
73 
74 	rc = i2c_master_recv(client, &byte, 1);
75 	if (rc != 1) {
76 		v4l2_dbg(1, debug, sd,
77 			"i2c_master_recv() failed\n");
78 		if (rc < 0)
79 			return rc;
80 		return -EIO;
81 	}
82 
83 	if (byte & 0x80) {
84 		v4l2_dbg(1, debug, sd,
85 			"TDA9840_DETECT: register contents invalid\n");
86 		return -EINVAL;
87 	}
88 
89 	v4l2_dbg(1, debug, sd, "TDA9840_DETECT: byte: 0x%02x\n", byte);
90 	return byte & 0x60;
91 }
92 
93 static int tda9840_s_tuner(struct v4l2_subdev *sd, const struct v4l2_tuner *t)
94 {
95 	int stat = tda9840_status(sd);
96 	int byte;
97 
98 	if (t->index)
99 		return -EINVAL;
100 
101 	stat = stat < 0 ? 0 : stat;
102 	if (stat == 0 || stat == 0x60) /* mono input */
103 		byte = TDA9840_SET_MONO;
104 	else if (stat == 0x40) /* stereo input */
105 		byte = (t->audmode == V4L2_TUNER_MODE_MONO) ?
106 			TDA9840_SET_MONO : TDA9840_SET_STEREO;
107 	else { /* bilingual */
108 		switch (t->audmode) {
109 		case V4L2_TUNER_MODE_LANG1_LANG2:
110 			byte = TDA9840_SET_BOTH;
111 			break;
112 		case V4L2_TUNER_MODE_LANG2:
113 			byte = TDA9840_SET_LANG2;
114 			break;
115 		default:
116 			byte = TDA9840_SET_LANG1;
117 			break;
118 		}
119 	}
120 	v4l2_dbg(1, debug, sd, "TDA9840_SWITCH: 0x%02x\n", byte);
121 	tda9840_write(sd, SWITCH, byte);
122 	return 0;
123 }
124 
125 static int tda9840_g_tuner(struct v4l2_subdev *sd, struct v4l2_tuner *t)
126 {
127 	int stat = tda9840_status(sd);
128 
129 	if (stat < 0)
130 		return stat;
131 
132 	t->rxsubchans = V4L2_TUNER_SUB_MONO;
133 
134 	switch (stat & 0x60) {
135 	case 0x00:
136 		t->rxsubchans = V4L2_TUNER_SUB_MONO;
137 		break;
138 	case 0x20:
139 		t->rxsubchans = V4L2_TUNER_SUB_LANG1 | V4L2_TUNER_SUB_LANG2;
140 		break;
141 	case 0x40:
142 		t->rxsubchans = V4L2_TUNER_SUB_STEREO | V4L2_TUNER_SUB_MONO;
143 		break;
144 	default: /* Incorrect detect */
145 		t->rxsubchans = V4L2_TUNER_MODE_MONO;
146 		break;
147 	}
148 	return 0;
149 }
150 
151 /* ----------------------------------------------------------------------- */
152 
153 static const struct v4l2_subdev_tuner_ops tda9840_tuner_ops = {
154 	.s_tuner = tda9840_s_tuner,
155 	.g_tuner = tda9840_g_tuner,
156 };
157 
158 static const struct v4l2_subdev_ops tda9840_ops = {
159 	.tuner = &tda9840_tuner_ops,
160 };
161 
162 /* ----------------------------------------------------------------------- */
163 
164 static int tda9840_probe(struct i2c_client *client,
165 			  const struct i2c_device_id *id)
166 {
167 	struct v4l2_subdev *sd;
168 
169 	/* let's see whether this adapter can support what we need */
170 	if (!i2c_check_functionality(client->adapter,
171 			I2C_FUNC_SMBUS_READ_BYTE_DATA |
172 			I2C_FUNC_SMBUS_WRITE_BYTE_DATA))
173 		return -EIO;
174 
175 	v4l_info(client, "chip found @ 0x%x (%s)\n",
176 			client->addr << 1, client->adapter->name);
177 
178 	sd = devm_kzalloc(&client->dev, sizeof(*sd), GFP_KERNEL);
179 	if (sd == NULL)
180 		return -ENOMEM;
181 	v4l2_i2c_subdev_init(sd, client, &tda9840_ops);
182 
183 	/* set initial values for level & stereo - adjustment, mode */
184 	tda9840_write(sd, LEVEL_ADJUST, 0);
185 	tda9840_write(sd, STEREO_ADJUST, 0);
186 	tda9840_write(sd, SWITCH, TDA9840_SET_STEREO);
187 	return 0;
188 }
189 
190 static int tda9840_remove(struct i2c_client *client)
191 {
192 	struct v4l2_subdev *sd = i2c_get_clientdata(client);
193 
194 	v4l2_device_unregister_subdev(sd);
195 	return 0;
196 }
197 
198 static const struct i2c_device_id tda9840_id[] = {
199 	{ "tda9840", 0 },
200 	{ }
201 };
202 MODULE_DEVICE_TABLE(i2c, tda9840_id);
203 
204 static struct i2c_driver tda9840_driver = {
205 	.driver = {
206 		.name	= "tda9840",
207 	},
208 	.probe		= tda9840_probe,
209 	.remove		= tda9840_remove,
210 	.id_table	= tda9840_id,
211 };
212 
213 module_i2c_driver(tda9840_driver);
214