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 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 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 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 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 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 /* ----------------------------------------------------------------------- */ 100 101 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 = cs3308_probe, 122 .remove = cs3308_remove, 123 .id_table = cs3308_id, 124 }; 125 126 module_i2c_driver(cs3308_driver); 127