ak881x.c

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/*
 * Driver for AK8813 / AK8814 TV-ecoders from Asahi Kasei Microsystems Co., Ltd. (AKM)
 *
 * Copyright (C) 2010, Guennadi Liakhovetski <[email protected]>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <linux/i2c.h>
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/videodev2.h>
#include <linux/module.h>

#include <media/ak881x.h>
#include <media/v4l2-chip-ident.h>
#include <media/v4l2-common.h>
#include <media/v4l2-device.h>

#define AK881X_INTERFACE_MODE   0
#define AK881X_VIDEO_PROCESS1   1
#define AK881X_VIDEO_PROCESS2   2
#define AK881X_VIDEO_PROCESS3   3
#define AK881X_DAC_MODE     5
#define AK881X_STATUS       0x24
#define AK881X_DEVICE_ID    0x25
#define AK881X_DEVICE_REVISION  0x26

struct ak881x {
    struct v4l2_subdev subdev;
    struct ak881x_pdata *pdata;
    unsigned int lines;
    int id; /* DEVICE_ID code V4L2_IDENT_AK881X code from v4l2-chip-ident.h */
    char revision;  /* DEVICE_REVISION content */
};

static int reg_read(struct i2c_client *client, const u8 reg)
{
    return i2c_smbus_read_byte_data(client, reg);
}

static int reg_write(struct i2c_client *client, const u8 reg,
             const u8 data)
{
    return i2c_smbus_write_byte_data(client, reg, data);
}

static int reg_set(struct i2c_client *client, const u8 reg,
           const u8 data, u8 mask)
{
    int ret = reg_read(client, reg);
    if (ret < 0)
        return ret;
    return reg_write(client, reg, (ret & ~mask) | (data & mask));
}

static struct ak881x *to_ak881x(const struct i2c_client *client)
{
    return container_of(i2c_get_clientdata(client), struct ak881x, subdev);
}

static int ak881x_g_chip_ident(struct v4l2_subdev *sd,
                   struct v4l2_dbg_chip_ident *id)
{
    struct i2c_client *client = v4l2_get_subdevdata(sd);
    struct ak881x *ak881x = to_ak881x(client);

    if (id->match.type != V4L2_CHIP_MATCH_I2C_ADDR)
        return -EINVAL;

    if (id->match.addr != client->addr)
        return -ENODEV;

    id->ident   = ak881x->id;
    id->revision    = ak881x->revision;

    return 0;
}

#ifdef CONFIG_VIDEO_ADV_DEBUG
static int ak881x_g_register(struct v4l2_subdev *sd,
                 struct v4l2_dbg_register *reg)
{
    struct i2c_client *client = v4l2_get_subdevdata(sd);

    if (reg->match.type != V4L2_CHIP_MATCH_I2C_ADDR || reg->reg > 0x26)
        return -EINVAL;

    if (reg->match.addr != client->addr)
        return -ENODEV;

    reg->val = reg_read(client, reg->reg);

    if (reg->val > 0xffff)
        return -EIO;

    return 0;
}

static int ak881x_s_register(struct v4l2_subdev *sd,
                 struct v4l2_dbg_register *reg)
{
    struct i2c_client *client = v4l2_get_subdevdata(sd);

    if (reg->match.type != V4L2_CHIP_MATCH_I2C_ADDR || reg->reg > 0x26)
        return -EINVAL;

    if (reg->match.addr != client->addr)
        return -ENODEV;

    if (reg_write(client, reg->reg, reg->val) < 0)
        return -EIO;

    return 0;
}
#endif

static int ak881x_try_g_mbus_fmt(struct v4l2_subdev *sd,
                 struct v4l2_mbus_framefmt *mf)
{
    struct i2c_client *client = v4l2_get_subdevdata(sd);
    struct ak881x *ak881x = to_ak881x(client);

    v4l_bound_align_image(&mf->width, 0, 720, 2,
                  &mf->height, 0, ak881x->lines, 1, 0);
    mf->field   = V4L2_FIELD_INTERLACED;
    mf->code    = V4L2_MBUS_FMT_YUYV8_2X8;
    mf->colorspace  = V4L2_COLORSPACE_SMPTE170M;

    return 0;
}

static int ak881x_s_mbus_fmt(struct v4l2_subdev *sd,
                 struct v4l2_mbus_framefmt *mf)
{
    if (mf->field != V4L2_FIELD_INTERLACED ||
        mf->code != V4L2_MBUS_FMT_YUYV8_2X8)
        return -EINVAL;

    return ak881x_try_g_mbus_fmt(sd, mf);
}

static int ak881x_enum_mbus_fmt(struct v4l2_subdev *sd, unsigned int index,
                enum v4l2_mbus_pixelcode *code)
{
    if (index)
        return -EINVAL;

    *code = V4L2_MBUS_FMT_YUYV8_2X8;
    return 0;
}

static int ak881x_cropcap(struct v4l2_subdev *sd, struct v4l2_cropcap *a)
{
    struct i2c_client *client = v4l2_get_subdevdata(sd);
    struct ak881x *ak881x = to_ak881x(client);

    a->bounds.left          = 0;
    a->bounds.top           = 0;
    a->bounds.width         = 720;
    a->bounds.height        = ak881x->lines;
    a->defrect          = a->bounds;
    a->type             = V4L2_BUF_TYPE_VIDEO_OUTPUT;
    a->pixelaspect.numerator    = 1;
    a->pixelaspect.denominator  = 1;

    return 0;
}

static int ak881x_s_std_output(struct v4l2_subdev *sd, v4l2_std_id std)
{
    struct i2c_client *client = v4l2_get_subdevdata(sd);
    struct ak881x *ak881x = to_ak881x(client);
    u8 vp1;

    if (std == V4L2_STD_NTSC_443) {
        vp1 = 3;
        ak881x->lines = 480;
    } else if (std == V4L2_STD_PAL_M) {
        vp1 = 5;
        ak881x->lines = 480;
    } else if (std == V4L2_STD_PAL_60) {
        vp1 = 7;
        ak881x->lines = 480;
    } else if (std && !(std & ~V4L2_STD_PAL)) {
        vp1 = 0xf;
        ak881x->lines = 576;
    } else if (std && !(std & ~V4L2_STD_NTSC)) {
        vp1 = 0;
        ak881x->lines = 480;
    } else {
        /* No SECAM or PAL_N/Nc supported */
        return -EINVAL;
    }

    reg_set(client, AK881X_VIDEO_PROCESS1, vp1, 0xf);

    return 0;
}

static int ak881x_s_stream(struct v4l2_subdev *sd, int enable)
{
    struct i2c_client *client = v4l2_get_subdevdata(sd);
    struct ak881x *ak881x = to_ak881x(client);

    if (enable) {
        u8 dac;
        /* For colour-bar testing set bit 6 of AK881X_VIDEO_PROCESS1 */
        /* Default: composite output */
        if (ak881x->pdata->flags & AK881X_COMPONENT)
            dac = 3;
        else
            dac = 4;
        /* Turn on the DAC(s) */
        reg_write(client, AK881X_DAC_MODE, dac);
        dev_dbg(&client->dev, "chip status 0x%x\n",
            reg_read(client, AK881X_STATUS));
    } else {
        /* ...and clear bit 6 of AK881X_VIDEO_PROCESS1 here */
        reg_write(client, AK881X_DAC_MODE, 0);
        dev_dbg(&client->dev, "chip status 0x%x\n",
            reg_read(client, AK881X_STATUS));
    }

    return 0;
}

static struct v4l2_subdev_core_ops ak881x_subdev_core_ops = {
    .g_chip_ident   = ak881x_g_chip_ident,
#ifdef CONFIG_VIDEO_ADV_DEBUG
    .g_register = ak881x_g_register,
    .s_register = ak881x_s_register,
#endif
};

static struct v4l2_subdev_video_ops ak881x_subdev_video_ops = {
    .s_mbus_fmt = ak881x_s_mbus_fmt,
    .g_mbus_fmt = ak881x_try_g_mbus_fmt,
    .try_mbus_fmt   = ak881x_try_g_mbus_fmt,
    .cropcap    = ak881x_cropcap,
    .enum_mbus_fmt  = ak881x_enum_mbus_fmt,
    .s_std_output   = ak881x_s_std_output,
    .s_stream   = ak881x_s_stream,
};

static struct v4l2_subdev_ops ak881x_subdev_ops = {
    .core   = &ak881x_subdev_core_ops,
    .video  = &ak881x_subdev_video_ops,
};

static int ak881x_probe(struct i2c_client *client,
            const struct i2c_device_id *did)
{
    struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
    struct ak881x *ak881x;
    u8 ifmode, data;

    if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) {
        dev_warn(&adapter->dev,
             "I2C-Adapter doesn't support I2C_FUNC_SMBUS_WORD\n");
        return -EIO;
    }

    ak881x = kzalloc(sizeof(struct ak881x), GFP_KERNEL);
    if (!ak881x)
        return -ENOMEM;

    v4l2_i2c_subdev_init(&ak881x->subdev, client, &ak881x_subdev_ops);

    data = reg_read(client, AK881X_DEVICE_ID);

    switch (data) {
    case 0x13:
        ak881x->id = V4L2_IDENT_AK8813;
        break;
    case 0x14:
        ak881x->id = V4L2_IDENT_AK8814;
        break;
    default:
        dev_err(&client->dev,
            "No ak881x chip detected, register read %x\n", data);
        kfree(ak881x);
        return -ENODEV;
    }

    ak881x->revision = reg_read(client, AK881X_DEVICE_REVISION);
    ak881x->pdata = client->dev.platform_data;

    if (ak881x->pdata) {
        if (ak881x->pdata->flags & AK881X_FIELD)
            ifmode = 4;
        else
            ifmode = 0;

        switch (ak881x->pdata->flags & AK881X_IF_MODE_MASK) {
        case AK881X_IF_MODE_BT656:
            ifmode |= 1;
            break;
        case AK881X_IF_MODE_MASTER:
            ifmode |= 2;
            break;
        case AK881X_IF_MODE_SLAVE:
        default:
            break;
        }

        dev_dbg(&client->dev, "IF mode %x\n", ifmode);

        /*
         * "Line Blanking No." seems to be the same as the number of
         * "black" lines on, e.g., SuperH VOU, whose default value of 20
         * "incidentally" matches ak881x' default
         */
        reg_write(client, AK881X_INTERFACE_MODE, ifmode | (20 << 3));
    }

    /* Hardware default: NTSC-M */
    ak881x->lines = 480;

    dev_info(&client->dev, "Detected an ak881x chip ID %x, revision %x\n",
         data, ak881x->revision);

    return 0;
}

static int ak881x_remove(struct i2c_client *client)
{
    struct ak881x *ak881x = to_ak881x(client);

    v4l2_device_unregister_subdev(&ak881x->subdev);
    kfree(ak881x);

    return 0;
}

static const struct i2c_device_id ak881x_id[] = {
    { "ak8813", 0 },
    { "ak8814", 0 },
    { }
};
MODULE_DEVICE_TABLE(i2c, ak881x_id);

static struct i2c_driver ak881x_i2c_driver = {
    .driver = {
        .name = "ak881x",
    },
    .probe      = ak881x_probe,
    .remove     = ak881x_remove,
    .id_table   = ak881x_id,
};

module_i2c_driver(ak881x_i2c_driver);

MODULE_DESCRIPTION("TV-output driver for ak8813/ak8814");
MODULE_AUTHOR("Guennadi Liakhovetski <[email protected]>");
MODULE_LICENSE("GPL v2");