LXR linux/drivers/media/i2c/cs3308.c

   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
  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_DEBUG
  38static 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#endif
  51
  52/* ----------------------------------------------------------------------- */
  53
  54static 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
  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                        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
 102static int 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        return 0;
 109}
 110
 111/* ----------------------------------------------------------------------- */
 112
 113static const struct i2c_device_id cs3308_id[] = {
 114        { "cs3308", 0 },
 115        { }
 116};
 117MODULE_DEVICE_TABLE(i2c, cs3308_id);
 118
 119static struct i2c_driver cs3308_driver = {
 120        .driver = {
 121                .name   = "cs3308",
 122        },
 123        .probe          = cs3308_probe,
 124        .remove         = cs3308_remove,
 125        .id_table       = cs3308_id,
 126};
 127
 128module_i2c_driver(cs3308_driver);
 129