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)67 static int cs3308_probe(struct i2c_client *client)
68 {
69 struct v4l2_subdev *sd;
70 unsigned i;
71
72 /* Check if the adapter supports the needed features */
73 if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
74 return -EIO;
75
76 if ((i2c_smbus_read_byte_data(client, 0x1c) & 0xf0) != 0xe0)
77 return -ENODEV;
78
79 v4l_info(client, "chip found @ 0x%x (%s)\n",
80 client->addr << 1, client->adapter->name);
81
82 sd = kzalloc(sizeof(struct v4l2_subdev), GFP_KERNEL);
83 if (sd == NULL)
84 return -ENOMEM;
85
86 v4l2_i2c_subdev_init(sd, client, &cs3308_ops);
87
88 /* Set some reasonable defaults */
89 cs3308_write(sd, 0x0d, 0x00); /* Power up all channels */
90 cs3308_write(sd, 0x0e, 0x00); /* Master Power */
91 cs3308_write(sd, 0x0b, 0x00); /* Device Configuration */
92 /* Set volume for each channel */
93 for (i = 1; i <= 8; i++)
94 cs3308_write(sd, i, 0xd2);
95 cs3308_write(sd, 0x0a, 0x00); /* Unmute all channels */
96 return 0;
97 }
98
99 /* ----------------------------------------------------------------------- */
100
cs3308_remove(struct i2c_client * client)101 static void cs3308_remove(struct i2c_client *client)
102 {
103 struct v4l2_subdev *sd = i2c_get_clientdata(client);
104
105 v4l2_device_unregister_subdev(sd);
106 kfree(sd);
107 }
108
109 /* ----------------------------------------------------------------------- */
110
111 static const struct i2c_device_id cs3308_id[] = {
112 { "cs3308", 0 },
113 { }
114 };
115 MODULE_DEVICE_TABLE(i2c, cs3308_id);
116
117 static struct i2c_driver cs3308_driver = {
118 .driver = {
119 .name = "cs3308",
120 },
121 .probe_new = cs3308_probe,
122 .remove = cs3308_remove,
123 .id_table = cs3308_id,
124 };
125
126 module_i2c_driver(cs3308_driver);
127