/*
 * cs5345 Cirrus Logic 24-bit, 192 kHz Stereo Audio ADC
 * Copyright (C) 2007 Hans Verkuil
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 */


#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/i2c.h>
#include <linux/videodev2.h>
#include <linux/slab.h>
#include <media/v4l2-device.h>
#include <media/v4l2-ctrls.h>

MODULE_DESCRIPTION("i2c device driver for cs5345 Audio ADC");
MODULE_AUTHOR("Hans Verkuil");
MODULE_LICENSE("GPL");

static bool debug;

module_param(debug, bool, 0644);

MODULE_PARM_DESC(debug, "Debugging messages, 0=Off (default), 1=On");

struct cs5345_state {
        struct v4l2_subdev sd;
        struct v4l2_ctrl_handler hdl;
};

static inline struct cs5345_state *to_state(struct v4l2_subdev *sd)
{
        return container_of(sd, struct cs5345_state, sd);
}

static inline struct v4l2_subdev *to_sd(struct v4l2_ctrl *ctrl)
{
        return &container_of(ctrl->handler, struct cs5345_state, hdl)->sd;
}

/* ----------------------------------------------------------------------- */

static inline int cs5345_write(struct v4l2_subdev *sd, u8 reg, u8 value)
{
        struct i2c_client *client = v4l2_get_subdevdata(sd);

        return i2c_smbus_write_byte_data(client, reg, value);
}

static inline int cs5345_read(struct v4l2_subdev *sd, u8 reg)
{
        struct i2c_client *client = v4l2_get_subdevdata(sd);

        return i2c_smbus_read_byte_data(client, reg);
}

static int cs5345_s_routing(struct v4l2_subdev *sd,
                            u32 input, u32 output, u32 config)
{
        if ((input & 0xf) > 6) {
                v4l2_err(sd, "Invalid input %d.\n", input);
                return -EINVAL;
        }
        cs5345_write(sd, 0x09, input & 0xf);
        cs5345_write(sd, 0x05, input & 0xf0);
        return 0;
}

static int cs5345_s_ctrl(struct v4l2_ctrl *ctrl)
{
        struct v4l2_subdev *sd = to_sd(ctrl);

        switch (ctrl->id) {
        case V4L2_CID_AUDIO_MUTE:
                cs5345_write(sd, 0x04, ctrl->val ? 0x80 : 0);
                return 0;
        case V4L2_CID_AUDIO_VOLUME:
                cs5345_write(sd, 0x07, ((u8)ctrl->val) & 0x3f);
                cs5345_write(sd, 0x08, ((u8)ctrl->val) & 0x3f);
                return 0;
        }
        return -EINVAL;
}

#ifdef CONFIG_VIDEO_ADV_DEBUG
static int cs5345_g_register(struct v4l2_subdev *sd, struct v4l2_dbg_register *reg)
{
        reg->size = 1;
        reg->val = cs5345_read(sd, reg->reg & 0x1f);
        return 0;
}

static int cs5345_s_register(struct v4l2_subdev *sd, const struct v4l2_dbg_register *reg)
{
        cs5345_write(sd, reg->reg & 0x1f, reg->val & 0xff);
        return 0;
}
#endif

static int cs5345_log_status(struct v4l2_subdev *sd)
{
        u8 v = cs5345_read(sd, 0x09) & 7;
        u8 m = cs5345_read(sd, 0x04);
        int vol = cs5345_read(sd, 0x08) & 0x3f;

        v4l2_info(sd, "Input:  %d%s\n", v,
                        (m & 0x80) ? " (muted)" : "");
        if (vol >= 32)
                vol = vol - 64;
        v4l2_info(sd, "Volume: %d dB\n", vol);
        return 0;
}

/* ----------------------------------------------------------------------- */

static const struct v4l2_ctrl_ops cs5345_ctrl_ops = {
        .s_ctrl = cs5345_s_ctrl,
};

static const struct v4l2_subdev_core_ops cs5345_core_ops = {
        .log_status = cs5345_log_status,
#ifdef CONFIG_VIDEO_ADV_DEBUG
        .g_register = cs5345_g_register,
        .s_register = cs5345_s_register,
#endif
};

static const struct v4l2_subdev_audio_ops cs5345_audio_ops = {
        .s_routing = cs5345_s_routing,
};

static const struct v4l2_subdev_ops cs5345_ops = {
        .core = &cs5345_core_ops,
        .audio = &cs5345_audio_ops,
};

/* ----------------------------------------------------------------------- */

static int cs5345_probe(struct i2c_client *client,
                        const struct i2c_device_id *id)
{
        struct cs5345_state *state;
        struct v4l2_subdev *sd;

        /* Check if the adapter supports the needed features */
        if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
                return -EIO;

        v4l_info(client, "chip found @ 0x%x (%s)\n",
                        client->addr << 1, client->adapter->name);

        state = devm_kzalloc(&client->dev, sizeof(*state), GFP_KERNEL);
        if (state == NULL)
                return -ENOMEM;
        sd = &state->sd;
        v4l2_i2c_subdev_init(sd, client, &cs5345_ops);

        v4l2_ctrl_handler_init(&state->hdl, 2);
        v4l2_ctrl_new_std(&state->hdl, &cs5345_ctrl_ops,
                        V4L2_CID_AUDIO_MUTE, 0, 1, 1, 0);
        v4l2_ctrl_new_std(&state->hdl, &cs5345_ctrl_ops,
                        V4L2_CID_AUDIO_VOLUME, -24, 24, 1, 0);
        sd->ctrl_handler = &state->hdl;
        if (state->hdl.error) {
                int err = state->hdl.error;

                v4l2_ctrl_handler_free(&state->hdl);
                return err;
        }
        /* set volume/mute */
        v4l2_ctrl_handler_setup(&state->hdl);

        cs5345_write(sd, 0x02, 0x00);
        cs5345_write(sd, 0x04, 0x01);
        cs5345_write(sd, 0x09, 0x01);
        return 0;
}

/* ----------------------------------------------------------------------- */

static int cs5345_remove(struct i2c_client *client)
{
        struct v4l2_subdev *sd = i2c_get_clientdata(client);
        struct cs5345_state *state = to_state(sd);

        v4l2_device_unregister_subdev(sd);
        v4l2_ctrl_handler_free(&state->hdl);
        return 0;
}

/* ----------------------------------------------------------------------- */

static const struct i2c_device_id cs5345_id[] = {
        { "cs5345", 0 },
        { }
};
MODULE_DEVICE_TABLE(i2c, cs5345_id);

static struct i2c_driver cs5345_driver = {
        .driver = {
                .name   = "cs5345",
        },
        .probe          = cs5345_probe,
        .remove         = cs5345_remove,
        .id_table       = cs5345_id,
};

module_i2c_driver(cs5345_driver);