1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 tda9840 - i2c-driver for the tda9840 by SGS Thomson
4
5 Copyright (C) 1998-2003 Michael Hunold <michael@mihu.de>
6 Copyright (C) 2008 Hans Verkuil <hverkuil@xs4all.nl>
7
8 The tda9840 is a stereo/dual sound processor with digital
9 identification. It can be found at address 0x84 on the i2c-bus.
10
11 For detailed information download the specifications directly
12 from SGS Thomson at http://www.st.com
13
14 */
15
16
17 #include <linux/module.h>
18 #include <linux/ioctl.h>
19 #include <linux/slab.h>
20 #include <linux/i2c.h>
21 #include <media/v4l2-device.h>
22
23 MODULE_AUTHOR("Michael Hunold <michael@mihu.de>");
24 MODULE_DESCRIPTION("tda9840 driver");
25 MODULE_LICENSE("GPL");
26
27 static int debug;
28 module_param(debug, int, 0644);
29
30 MODULE_PARM_DESC(debug, "Debug level (0-1)");
31
32 #define SWITCH 0x00
33 #define LEVEL_ADJUST 0x02
34 #define STEREO_ADJUST 0x03
35 #define TEST 0x04
36
37 #define TDA9840_SET_MUTE 0x00
38 #define TDA9840_SET_MONO 0x10
39 #define TDA9840_SET_STEREO 0x2a
40 #define TDA9840_SET_LANG1 0x12
41 #define TDA9840_SET_LANG2 0x1e
42 #define TDA9840_SET_BOTH 0x1a
43 #define TDA9840_SET_BOTH_R 0x16
44 #define TDA9840_SET_EXTERNAL 0x7a
45
46
tda9840_write(struct v4l2_subdev * sd,u8 reg,u8 val)47 static void tda9840_write(struct v4l2_subdev *sd, u8 reg, u8 val)
48 {
49 struct i2c_client *client = v4l2_get_subdevdata(sd);
50
51 if (i2c_smbus_write_byte_data(client, reg, val))
52 v4l2_dbg(1, debug, sd, "error writing %02x to %02x\n",
53 val, reg);
54 }
55
tda9840_status(struct v4l2_subdev * sd)56 static int tda9840_status(struct v4l2_subdev *sd)
57 {
58 struct i2c_client *client = v4l2_get_subdevdata(sd);
59 int rc;
60 u8 byte;
61
62 rc = i2c_master_recv(client, &byte, 1);
63 if (rc != 1) {
64 v4l2_dbg(1, debug, sd,
65 "i2c_master_recv() failed\n");
66 if (rc < 0)
67 return rc;
68 return -EIO;
69 }
70
71 if (byte & 0x80) {
72 v4l2_dbg(1, debug, sd,
73 "TDA9840_DETECT: register contents invalid\n");
74 return -EINVAL;
75 }
76
77 v4l2_dbg(1, debug, sd, "TDA9840_DETECT: byte: 0x%02x\n", byte);
78 return byte & 0x60;
79 }
80
tda9840_s_tuner(struct v4l2_subdev * sd,const struct v4l2_tuner * t)81 static int tda9840_s_tuner(struct v4l2_subdev *sd, const struct v4l2_tuner *t)
82 {
83 int stat = tda9840_status(sd);
84 int byte;
85
86 if (t->index)
87 return -EINVAL;
88
89 stat = stat < 0 ? 0 : stat;
90 if (stat == 0 || stat == 0x60) /* mono input */
91 byte = TDA9840_SET_MONO;
92 else if (stat == 0x40) /* stereo input */
93 byte = (t->audmode == V4L2_TUNER_MODE_MONO) ?
94 TDA9840_SET_MONO : TDA9840_SET_STEREO;
95 else { /* bilingual */
96 switch (t->audmode) {
97 case V4L2_TUNER_MODE_LANG1_LANG2:
98 byte = TDA9840_SET_BOTH;
99 break;
100 case V4L2_TUNER_MODE_LANG2:
101 byte = TDA9840_SET_LANG2;
102 break;
103 default:
104 byte = TDA9840_SET_LANG1;
105 break;
106 }
107 }
108 v4l2_dbg(1, debug, sd, "TDA9840_SWITCH: 0x%02x\n", byte);
109 tda9840_write(sd, SWITCH, byte);
110 return 0;
111 }
112
tda9840_g_tuner(struct v4l2_subdev * sd,struct v4l2_tuner * t)113 static int tda9840_g_tuner(struct v4l2_subdev *sd, struct v4l2_tuner *t)
114 {
115 int stat = tda9840_status(sd);
116
117 if (stat < 0)
118 return stat;
119
120 t->rxsubchans = V4L2_TUNER_SUB_MONO;
121
122 switch (stat & 0x60) {
123 case 0x00:
124 t->rxsubchans = V4L2_TUNER_SUB_MONO;
125 break;
126 case 0x20:
127 t->rxsubchans = V4L2_TUNER_SUB_LANG1 | V4L2_TUNER_SUB_LANG2;
128 break;
129 case 0x40:
130 t->rxsubchans = V4L2_TUNER_SUB_STEREO | V4L2_TUNER_SUB_MONO;
131 break;
132 default: /* Incorrect detect */
133 t->rxsubchans = V4L2_TUNER_MODE_MONO;
134 break;
135 }
136 return 0;
137 }
138
139 /* ----------------------------------------------------------------------- */
140
141 static const struct v4l2_subdev_tuner_ops tda9840_tuner_ops = {
142 .s_tuner = tda9840_s_tuner,
143 .g_tuner = tda9840_g_tuner,
144 };
145
146 static const struct v4l2_subdev_ops tda9840_ops = {
147 .tuner = &tda9840_tuner_ops,
148 };
149
150 /* ----------------------------------------------------------------------- */
151
tda9840_probe(struct i2c_client * client,const struct i2c_device_id * id)152 static int tda9840_probe(struct i2c_client *client,
153 const struct i2c_device_id *id)
154 {
155 struct v4l2_subdev *sd;
156
157 /* let's see whether this adapter can support what we need */
158 if (!i2c_check_functionality(client->adapter,
159 I2C_FUNC_SMBUS_READ_BYTE_DATA |
160 I2C_FUNC_SMBUS_WRITE_BYTE_DATA))
161 return -EIO;
162
163 v4l_info(client, "chip found @ 0x%x (%s)\n",
164 client->addr << 1, client->adapter->name);
165
166 sd = devm_kzalloc(&client->dev, sizeof(*sd), GFP_KERNEL);
167 if (sd == NULL)
168 return -ENOMEM;
169 v4l2_i2c_subdev_init(sd, client, &tda9840_ops);
170
171 /* set initial values for level & stereo - adjustment, mode */
172 tda9840_write(sd, LEVEL_ADJUST, 0);
173 tda9840_write(sd, STEREO_ADJUST, 0);
174 tda9840_write(sd, SWITCH, TDA9840_SET_STEREO);
175 return 0;
176 }
177
tda9840_remove(struct i2c_client * client)178 static int tda9840_remove(struct i2c_client *client)
179 {
180 struct v4l2_subdev *sd = i2c_get_clientdata(client);
181
182 v4l2_device_unregister_subdev(sd);
183 return 0;
184 }
185
186 static const struct i2c_device_id tda9840_id[] = {
187 { "tda9840", 0 },
188 { }
189 };
190 MODULE_DEVICE_TABLE(i2c, tda9840_id);
191
192 static struct i2c_driver tda9840_driver = {
193 .driver = {
194 .name = "tda9840",
195 },
196 .probe = tda9840_probe,
197 .remove = tda9840_remove,
198 .id_table = tda9840_id,
199 };
200
201 module_i2c_driver(tda9840_driver);
202