/*
 * upd6408x - NEC Electronics 3-Dimensional Y/C separation driver
 *
 * 2003 by T.Adachi (tadachi@tadachi-net.com)
 * 2003 by Takeru KOMORIYA <komoriya@paken.org>
 * 2006 by Hans Verkuil <hverkuil@xs4all.nl>
 *
 * 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., 51 Franklin Street, Fifth Floor, Boston, MA
 * 02110-1301, USA.
 */

#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/upd64083.h>

MODULE_DESCRIPTION("uPD64083 driver");
MODULE_AUTHOR("T. Adachi, Takeru KOMORIYA, Hans Verkuil");
MODULE_LICENSE("GPL");

static bool debug;
module_param(debug, bool, 0644);

MODULE_PARM_DESC(debug, "Debug level (0-1)");


enum {
        R00 = 0, R01, R02, R03, R04,
        R05, R06, R07, R08, R09,
        R0A, R0B, R0C, R0D, R0E, R0F,
        R10, R11, R12, R13, R14,
        R15, R16,
        TOT_REGS
};

struct upd64083_state {
        struct v4l2_subdev sd;
        u8 mode;
        u8 ext_y_adc;
        u8 regs[TOT_REGS];
};

static inline struct upd64083_state *to_state(struct v4l2_subdev *sd)
{
        return container_of(sd, struct upd64083_state, sd);
}

/* Initial values when used in combination with the
   NEC upd64031a ghost reduction chip. */
static u8 upd64083_init[] = {
        0x1f, 0x01, 0xa0, 0x2d, 0x29,  /* we use EXCSS=0 */
        0x36, 0xdd, 0x05, 0x56, 0x48,
        0x00, 0x3a, 0xa0, 0x05, 0x08,
        0x44, 0x60, 0x08, 0x52, 0xf8,
        0x53, 0x60, 0x10
};

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

static void upd64083_write(struct v4l2_subdev *sd, u8 reg, u8 val)
{
        struct i2c_client *client = v4l2_get_subdevdata(sd);
        u8 buf[2];

        buf[0] = reg;
        buf[1] = val;
        v4l2_dbg(1, debug, sd, "write reg: %02x val: %02x\n", reg, val);
        if (i2c_master_send(client, buf, 2) != 2)
                v4l2_err(sd, "I/O error write 0x%02x/0x%02x\n", reg, val);
}

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

#ifdef CONFIG_VIDEO_ADV_DEBUG
static u8 upd64083_read(struct v4l2_subdev *sd, u8 reg)
{
        struct i2c_client *client = v4l2_get_subdevdata(sd);
        u8 buf[7];

        if (reg >= sizeof(buf))
                return 0xff;
        i2c_master_recv(client, buf, sizeof(buf));
        return buf[reg];
}
#endif

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

static int upd64083_s_routing(struct v4l2_subdev *sd,
                              u32 input, u32 output, u32 config)
{
        struct upd64083_state *state = to_state(sd);
        u8 r00, r02;

        if (input > 7 || (input & 6) == 6)
                return -EINVAL;
        state->mode = (input & 3) << 6;
        state->ext_y_adc = (input & UPD64083_EXT_Y_ADC) << 3;
        r00 = (state->regs[R00] & ~(3 << 6)) | state->mode;
        r02 = (state->regs[R02] & ~(1 << 5)) | state->ext_y_adc;
        upd64083_write(sd, R00, r00);
        upd64083_write(sd, R02, r02);
        return 0;
}

#ifdef CONFIG_VIDEO_ADV_DEBUG
static int upd64083_g_register(struct v4l2_subdev *sd, struct v4l2_dbg_register *reg)
{
        reg->val = upd64083_read(sd, reg->reg & 0xff);
        reg->size = 1;
        return 0;
}

static int upd64083_s_register(struct v4l2_subdev *sd, const struct v4l2_dbg_register *reg)
{
        upd64083_write(sd, reg->reg & 0xff, reg->val & 0xff);
        return 0;
}
#endif

static int upd64083_log_status(struct v4l2_subdev *sd)
{
        struct i2c_client *client = v4l2_get_subdevdata(sd);
        u8 buf[7];

        i2c_master_recv(client, buf, 7);
        v4l2_info(sd, "Status: SA00=%02x SA01=%02x SA02=%02x SA03=%02x "
                      "SA04=%02x SA05=%02x SA06=%02x\n",
                buf[0], buf[1], buf[2], buf[3], buf[4], buf[5], buf[6]);
        return 0;
}

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

static const struct v4l2_subdev_core_ops upd64083_core_ops = {
        .log_status = upd64083_log_status,
#ifdef CONFIG_VIDEO_ADV_DEBUG
        .g_register = upd64083_g_register,
        .s_register = upd64083_s_register,
#endif
};

static const struct v4l2_subdev_video_ops upd64083_video_ops = {
        .s_routing = upd64083_s_routing,
};

static const struct v4l2_subdev_ops upd64083_ops = {
        .core = &upd64083_core_ops,
        .video = &upd64083_video_ops,
};

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

/* i2c implementation */

static int upd64083_probe(struct i2c_client *client,
                          const struct i2c_device_id *id)
{
        struct upd64083_state *state;
        struct v4l2_subdev *sd;
        int i;

        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, &upd64083_ops);
        /* Initially assume that a ghost reduction chip is present */
        state->mode = 0;  /* YCS mode */
        state->ext_y_adc = (1 << 5);
        memcpy(state->regs, upd64083_init, TOT_REGS);
        for (i = 0; i < TOT_REGS; i++)
                upd64083_write(sd, i, state->regs[i]);
        return 0;
}

static int upd64083_remove(struct i2c_client *client)
{
        struct v4l2_subdev *sd = i2c_get_clientdata(client);

        v4l2_device_unregister_subdev(sd);
        return 0;
}

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

static const struct i2c_device_id upd64083_id[] = {
        { "upd64083", 0 },
        { }
};
MODULE_DEVICE_TABLE(i2c, upd64083_id);

static struct i2c_driver upd64083_driver = {
        .driver = {
                .owner  = THIS_MODULE,
                .name   = "upd64083",
        },
        .probe          = upd64083_probe,
        .remove         = upd64083_remove,
        .id_table       = upd64083_id,
};

module_i2c_driver(upd64083_driver);