// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * vp27smpx - driver version 0.0.1
 *
 * Copyright (C) 2007 Hans Verkuil <hverkuil@kernel.org>
 *
 * Based on a tvaudio patch from Takahiro Adachi <tadachi@tadachi-net.com>
 * and Kazuhiko Kawakami <kazz-0@mail.goo.ne.jp>
 */

#include <linux/module.h>
#include <linux/types.h>
#include <linux/slab.h>
#include <linux/ioctl.h>
#include <linux/uaccess.h>
#include <linux/i2c.h>
#include <linux/videodev2.h>
#include <media/v4l2-device.h>

MODULE_DESCRIPTION("vp27smpx driver");
MODULE_AUTHOR("Hans Verkuil");
MODULE_LICENSE("GPL");


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

struct vp27smpx_state {
        struct v4l2_subdev sd;
        int radio;
        u32 audmode;
};

static inline struct vp27smpx_state *to_state(struct v4l2_subdev *sd)
{
        return container_of(sd, struct vp27smpx_state, sd);
}

static void vp27smpx_set_audmode(struct v4l2_subdev *sd, u32 audmode)
{
        struct vp27smpx_state *state = to_state(sd);
        struct i2c_client *client = v4l2_get_subdevdata(sd);
        u8 data[3] = { 0x00, 0x00, 0x04 };

        switch (audmode) {
        case V4L2_TUNER_MODE_MONO:
        case V4L2_TUNER_MODE_LANG1:
                break;
        case V4L2_TUNER_MODE_STEREO:
        case V4L2_TUNER_MODE_LANG1_LANG2:
                data[1] = 0x01;
                break;
        case V4L2_TUNER_MODE_LANG2:
                data[1] = 0x02;
                break;
        }

        if (i2c_master_send(client, data, sizeof(data)) != sizeof(data))
                v4l2_err(sd, "I/O error setting audmode\n");
        else
                state->audmode = audmode;
}

static int vp27smpx_s_radio(struct v4l2_subdev *sd)
{
        struct vp27smpx_state *state = to_state(sd);

        state->radio = 1;
        return 0;
}

static int vp27smpx_s_std(struct v4l2_subdev *sd, v4l2_std_id norm)
{
        struct vp27smpx_state *state = to_state(sd);

        state->radio = 0;
        return 0;
}

static int vp27smpx_s_tuner(struct v4l2_subdev *sd, const struct v4l2_tuner *vt)
{
        struct vp27smpx_state *state = to_state(sd);

        if (!state->radio)
                vp27smpx_set_audmode(sd, vt->audmode);
        return 0;
}

static int vp27smpx_g_tuner(struct v4l2_subdev *sd, struct v4l2_tuner *vt)
{
        struct vp27smpx_state *state = to_state(sd);

        if (state->radio)
                return 0;
        vt->audmode = state->audmode;
        vt->capability = V4L2_TUNER_CAP_STEREO |
                V4L2_TUNER_CAP_LANG1 | V4L2_TUNER_CAP_LANG2;
        vt->rxsubchans = V4L2_TUNER_SUB_MONO;
        return 0;
}

static int vp27smpx_log_status(struct v4l2_subdev *sd)
{
        struct vp27smpx_state *state = to_state(sd);

        v4l2_info(sd, "Audio Mode: %u%s\n", state->audmode,
                        state->radio ? " (Radio)" : "");
        return 0;
}

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

static const struct v4l2_subdev_core_ops vp27smpx_core_ops = {
        .log_status = vp27smpx_log_status,
};

static const struct v4l2_subdev_tuner_ops vp27smpx_tuner_ops = {
        .s_radio = vp27smpx_s_radio,
        .s_tuner = vp27smpx_s_tuner,
        .g_tuner = vp27smpx_g_tuner,
};

static const struct v4l2_subdev_video_ops vp27smpx_video_ops = {
        .s_std = vp27smpx_s_std,
};

static const struct v4l2_subdev_ops vp27smpx_ops = {
        .core = &vp27smpx_core_ops,
        .tuner = &vp27smpx_tuner_ops,
        .video = &vp27smpx_video_ops,
};

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

/* i2c implementation */

/*
 * Generic i2c probe
 * concerning the addresses: i2c wants 7 bit (without the r/w bit), so '>>1'
 */

static int vp27smpx_probe(struct i2c_client *client)
{
        struct vp27smpx_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, &vp27smpx_ops);
        state->audmode = V4L2_TUNER_MODE_STEREO;

        /* initialize vp27smpx */
        vp27smpx_set_audmode(sd, state->audmode);
        return 0;
}

static void vp27smpx_remove(struct i2c_client *client)
{
        struct v4l2_subdev *sd = i2c_get_clientdata(client);

        v4l2_device_unregister_subdev(sd);
}

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

static const struct i2c_device_id vp27smpx_id[] = {
        { "vp27smpx" },
        { }
};
MODULE_DEVICE_TABLE(i2c, vp27smpx_id);

static struct i2c_driver vp27smpx_driver = {
        .driver = {
                .name   = "vp27smpx",
        },
        .probe          = vp27smpx_probe,
        .remove         = vp27smpx_remove,
        .id_table       = vp27smpx_id,
};

module_i2c_driver(vp27smpx_driver);