1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Cirrus Logic cs3308 8-Channel Analog Volume Control
4 *
5 * Copyright (C) 2010 Devin Heitmueller <dheitmueller@kernellabs.com>
6 * Copyright (C) 2012 Steven Toth <stoth@kernellabs.com>
7 *
8 * Derived from cs5345.c Copyright (C) 2007 Hans Verkuil
9 */
10
11
12 #include <linux/module.h>
13 #include <linux/kernel.h>
14 #include <linux/i2c.h>
15 #include <linux/slab.h>
16 #include <linux/videodev2.h>
17 #include <media/v4l2-device.h>
18
19 MODULE_DESCRIPTION("i2c device driver for cs3308 8-channel volume control");
20 MODULE_AUTHOR("Devin Heitmueller");
21 MODULE_LICENSE("GPL");
22
cs3308_write(struct v4l2_subdev * sd,u8 reg,u8 value)23 static inline int cs3308_write(struct v4l2_subdev *sd, u8 reg, u8 value)
24 {
25 struct i2c_client *client = v4l2_get_subdevdata(sd);
26
27 return i2c_smbus_write_byte_data(client, reg, value);
28 }
29
cs3308_read(struct v4l2_subdev * sd,u8 reg)30 static inline int cs3308_read(struct v4l2_subdev *sd, u8 reg)
31 {
32 struct i2c_client *client = v4l2_get_subdevdata(sd);
33
34 return i2c_smbus_read_byte_data(client, reg);
35 }
36
37 #ifdef CONFIG_VIDEO_ADV_DEBUG
cs3308_g_register(struct v4l2_subdev * sd,struct v4l2_dbg_register * reg)38 static int cs3308_g_register(struct v4l2_subdev *sd, struct v4l2_dbg_register *reg)
39 {
40 reg->val = cs3308_read(sd, reg->reg & 0xffff);
41 reg->size = 1;
42 return 0;
43 }
44
cs3308_s_register(struct v4l2_subdev * sd,const struct v4l2_dbg_register * reg)45 static int cs3308_s_register(struct v4l2_subdev *sd, const struct v4l2_dbg_register *reg)
46 {
47 cs3308_write(sd, reg->reg & 0xffff, reg->val & 0xff);
48 return 0;
49 }
50 #endif
51
52 /* ----------------------------------------------------------------------- */
53
54 static const struct v4l2_subdev_core_ops cs3308_core_ops = {
55 #ifdef CONFIG_VIDEO_ADV_DEBUG
56 .g_register = cs3308_g_register,
57 .s_register = cs3308_s_register,
58 #endif
59 };
60
61 static const struct v4l2_subdev_ops cs3308_ops = {
62 .core = &cs3308_core_ops,
63 };
64
65 /* ----------------------------------------------------------------------- */
66
cs3308_probe(struct i2c_client * client,const struct i2c_device_id * id)67 static int cs3308_probe(struct i2c_client *client,
68 const struct i2c_device_id *id)
69 {
70 struct v4l2_subdev *sd;
71 unsigned i;
72
73 /* Check if the adapter supports the needed features */
74 if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
75 return -EIO;
76
77 if ((i2c_smbus_read_byte_data(client, 0x1c) & 0xf0) != 0xe0)
78 return -ENODEV;
79
80 v4l_info(client, "chip found @ 0x%x (%s)\n",
81 client->addr << 1, client->adapter->name);
82
83 sd = kzalloc(sizeof(struct v4l2_subdev), GFP_KERNEL);
84 if (sd == NULL)
85 return -ENOMEM;
86
87 v4l2_i2c_subdev_init(sd, client, &cs3308_ops);
88
89 /* Set some reasonable defaults */
90 cs3308_write(sd, 0x0d, 0x00); /* Power up all channels */
91 cs3308_write(sd, 0x0e, 0x00); /* Master Power */
92 cs3308_write(sd, 0x0b, 0x00); /* Device Configuration */
93 /* Set volume for each channel */
94 for (i = 1; i <= 8; i++)
95 cs3308_write(sd, i, 0xd2);
96 cs3308_write(sd, 0x0a, 0x00); /* Unmute all channels */
97 return 0;
98 }
99
100 /* ----------------------------------------------------------------------- */
101
cs3308_remove(struct i2c_client * client)102 static void cs3308_remove(struct i2c_client *client)
103 {
104 struct v4l2_subdev *sd = i2c_get_clientdata(client);
105
106 v4l2_device_unregister_subdev(sd);
107 kfree(sd);
108 }
109
110 /* ----------------------------------------------------------------------- */
111
112 static const struct i2c_device_id cs3308_id[] = {
113 { "cs3308", 0 },
114 { }
115 };
116 MODULE_DEVICE_TABLE(i2c, cs3308_id);
117
118 static struct i2c_driver cs3308_driver = {
119 .driver = {
120 .name = "cs3308",
121 },
122 .probe = cs3308_probe,
123 .remove = cs3308_remove,
124 .id_table = cs3308_id,
125 };
126
127 module_i2c_driver(cs3308_driver);
128