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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * Cirrus Logic cs3308 8-Channel Analog Volume Control4 *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 Verkuil9 */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 19MODULE_DESCRIPTION("i2c device driver for cs3308 8-channel volume control");20MODULE_AUTHOR("Devin Heitmueller");21MODULE_LICENSE("GPL");22 23static 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 30static 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_DEBUG38static 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 45static 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#endif51 52/* ----------------------------------------------------------------------- */53 54static const struct v4l2_subdev_core_ops cs3308_core_ops = {55#ifdef CONFIG_VIDEO_ADV_DEBUG56 .g_register = cs3308_g_register,57 .s_register = cs3308_s_register,58#endif59};60 61static const struct v4l2_subdev_ops cs3308_ops = {62 .core = &cs3308_core_ops,63};64 65/* ----------------------------------------------------------------------- */66 67static 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 101static 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 111static const struct i2c_device_id cs3308_id[] = {112 { "cs3308" },113 { }114};115MODULE_DEVICE_TABLE(i2c, cs3308_id);116 117static 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 126module_i2c_driver(cs3308_driver);127