vp27smpx.c

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/*
 * vp27smpx - driver version 0.0.1
 *
 * Copyright (C) 2007 Hans Verkuil <[email protected]>
 *
 * Based on a tvaudio patch from Takahiro Adachi <[email protected]>
 * and Kazuhiko Kawakami <[email protected]>
 *
 * 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.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include <linux/module.h>
#include <linux/types.h>
#include <linux/slab.h>
#include <linux/ioctl.h>
#include <asm/uaccess.h>
#include <linux/i2c.h>
#include <linux/videodev2.h>
#include <media/v4l2-device.h>
#include <media/v4l2-chip-ident.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, 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_g_chip_ident(struct v4l2_subdev *sd, struct v4l2_dbg_chip_ident *chip)
{
    struct i2c_client *client = v4l2_get_subdevdata(sd);

    return v4l2_chip_ident_i2c_client(client, chip, V4L2_IDENT_VP27SMPX, 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,
    .g_chip_ident = vp27smpx_g_chip_ident,
    .s_std = vp27smpx_s_std,
};

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_ops vp27smpx_ops = {
    .core = &vp27smpx_core_ops,
    .tuner = &vp27smpx_tuner_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,
              const struct i2c_device_id *id)
{
    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 = kzalloc(sizeof(struct vp27smpx_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 int vp27smpx_remove(struct i2c_client *client)
{
    struct v4l2_subdev *sd = i2c_get_clientdata(client);

    v4l2_device_unregister_subdev(sd);
    kfree(to_state(sd));
    return 0;
}

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

static const struct i2c_device_id vp27smpx_id[] = {
    { "vp27smpx", 0 },
    { }
};
MODULE_DEVICE_TABLE(i2c, vp27smpx_id);

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

module_i2c_driver(vp27smpx_driver);