/*
 * tw9910 Video Driver
 *
 * Copyright (C) 2008 Renesas Solutions Corp.
 * Kuninori Morimoto <morimoto.kuninori@renesas.com>
 *
 * Based on ov772x driver,
 *
 * Copyright (C) 2008 Kuninori Morimoto <morimoto.kuninori@renesas.com>
 * Copyright 2006-7 Jonathan Corbet <corbet@lwn.net>
 * Copyright (C) 2008 Magnus Damm
 * Copyright (C) 2008, Guennadi Liakhovetski <kernel@pengutronix.de>
 *
 * 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/init.h>
#include <linux/module.h>
#include <linux/i2c.h>
#include <linux/slab.h>
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/v4l2-mediabus.h>
#include <linux/videodev2.h>

#include <media/soc_camera.h>
#include <media/i2c/tw9910.h>
#include <media/v4l2-clk.h>
#include <media/v4l2-subdev.h>

#define GET_ID(val)  ((val & 0xF8) >> 3)
#define GET_REV(val) (val & 0x07)

/*
 * register offset
 */
#define ID              0x00 /* Product ID Code Register */
#define STATUS1         0x01 /* Chip Status Register I */
#define INFORM          0x02 /* Input Format */
#define OPFORM          0x03 /* Output Format Control Register */
#define DLYCTR          0x04 /* Hysteresis and HSYNC Delay Control */
#define OUTCTR1         0x05 /* Output Control I */
#define ACNTL1          0x06 /* Analog Control Register 1 */
#define CROP_HI         0x07 /* Cropping Register, High */
#define VDELAY_LO       0x08 /* Vertical Delay Register, Low */
#define VACTIVE_LO      0x09 /* Vertical Active Register, Low */
#define HDELAY_LO       0x0A /* Horizontal Delay Register, Low */
#define HACTIVE_LO      0x0B /* Horizontal Active Register, Low */
#define CNTRL1          0x0C /* Control Register I */
#define VSCALE_LO       0x0D /* Vertical Scaling Register, Low */
#define SCALE_HI        0x0E /* Scaling Register, High */
#define HSCALE_LO       0x0F /* Horizontal Scaling Register, Low */
#define BRIGHT          0x10 /* BRIGHTNESS Control Register */
#define CONTRAST        0x11 /* CONTRAST Control Register */
#define SHARPNESS       0x12 /* SHARPNESS Control Register I */
#define SAT_U           0x13 /* Chroma (U) Gain Register */
#define SAT_V           0x14 /* Chroma (V) Gain Register */
#define HUE             0x15 /* Hue Control Register */
#define CORING1         0x17
#define CORING2         0x18 /* Coring and IF compensation */
#define VBICNTL         0x19 /* VBI Control Register */
#define ACNTL2          0x1A /* Analog Control 2 */
#define OUTCTR2         0x1B /* Output Control 2 */
#define SDT             0x1C /* Standard Selection */
#define SDTR            0x1D /* Standard Recognition */
#define TEST            0x1F /* Test Control Register */
#define CLMPG           0x20 /* Clamping Gain */
#define IAGC            0x21 /* Individual AGC Gain */
#define AGCGAIN         0x22 /* AGC Gain */
#define PEAKWT          0x23 /* White Peak Threshold */
#define CLMPL           0x24 /* Clamp level */
#define SYNCT           0x25 /* Sync Amplitude */
#define MISSCNT         0x26 /* Sync Miss Count Register */
#define PCLAMP          0x27 /* Clamp Position Register */
#define VCNTL1          0x28 /* Vertical Control I */
#define VCNTL2          0x29 /* Vertical Control II */
#define CKILL           0x2A /* Color Killer Level Control */
#define COMB            0x2B /* Comb Filter Control */
#define LDLY            0x2C /* Luma Delay and H Filter Control */
#define MISC1           0x2D /* Miscellaneous Control I */
#define LOOP            0x2E /* LOOP Control Register */
#define MISC2           0x2F /* Miscellaneous Control II */
#define MVSN            0x30 /* Macrovision Detection */
#define STATUS2         0x31 /* Chip STATUS II */
#define HFREF           0x32 /* H monitor */
#define CLMD            0x33 /* CLAMP MODE */
#define IDCNTL          0x34 /* ID Detection Control */
#define CLCNTL1         0x35 /* Clamp Control I */
#define ANAPLLCTL       0x4C
#define VBIMIN          0x4D
#define HSLOWCTL        0x4E
#define WSS3            0x4F
#define FILLDATA        0x50
#define SDID            0x51
#define DID             0x52
#define WSS1            0x53
#define WSS2            0x54
#define VVBI            0x55
#define LCTL6           0x56
#define LCTL7           0x57
#define LCTL8           0x58
#define LCTL9           0x59
#define LCTL10          0x5A
#define LCTL11          0x5B
#define LCTL12          0x5C
#define LCTL13          0x5D
#define LCTL14          0x5E
#define LCTL15          0x5F
#define LCTL16          0x60
#define LCTL17          0x61
#define LCTL18          0x62
#define LCTL19          0x63
#define LCTL20          0x64
#define LCTL21          0x65
#define LCTL22          0x66
#define LCTL23          0x67
#define LCTL24          0x68
#define LCTL25          0x69
#define LCTL26          0x6A
#define HSBEGIN         0x6B
#define HSEND           0x6C
#define OVSDLY          0x6D
#define OVSEND          0x6E
#define VBIDELAY        0x6F

/*
 * register detail
 */

/* INFORM */
#define FC27_ON     0x40 /* 1 : Input crystal clock frequency is 27MHz */
#define FC27_FF     0x00 /* 0 : Square pixel mode. */
                         /*     Must use 24.54MHz for 60Hz field rate */
                         /*     source or 29.5MHz for 50Hz field rate */
#define IFSEL_S     0x10 /* 01 : S-video decoding */
#define IFSEL_C     0x00 /* 00 : Composite video decoding */
                         /* Y input video selection */
#define YSEL_M0     0x00 /*  00 : Mux0 selected */
#define YSEL_M1     0x04 /*  01 : Mux1 selected */
#define YSEL_M2     0x08 /*  10 : Mux2 selected */
#define YSEL_M3     0x10 /*  11 : Mux3 selected */

/* OPFORM */
#define MODE        0x80 /* 0 : CCIR601 compatible YCrCb 4:2:2 format */
                         /* 1 : ITU-R-656 compatible data sequence format */
#define LEN         0x40 /* 0 : 8-bit YCrCb 4:2:2 output format */
                         /* 1 : 16-bit YCrCb 4:2:2 output format.*/
#define LLCMODE     0x20 /* 1 : LLC output mode. */
                         /* 0 : free-run output mode */
#define AINC        0x10 /* Serial interface auto-indexing control */
                         /* 0 : auto-increment */
                         /* 1 : non-auto */
#define VSCTL       0x08 /* 1 : Vertical out ctrl by DVALID */
                         /* 0 : Vertical out ctrl by HACTIVE and DVALID */
#define OEN_TRI_SEL_MASK        0x07
#define OEN_TRI_SEL_ALL_ON      0x00 /* Enable output for Rev0/Rev1 */
#define OEN_TRI_SEL_ALL_OFF_r0  0x06 /* All tri-stated for Rev0 */
#define OEN_TRI_SEL_ALL_OFF_r1  0x07 /* All tri-stated for Rev1 */

/* OUTCTR1 */
#define VSP_LO      0x00 /* 0 : VS pin output polarity is active low */
#define VSP_HI      0x80 /* 1 : VS pin output polarity is active high. */
                         /* VS pin output control */
#define VSSL_VSYNC  0x00 /*   0 : VSYNC  */
#define VSSL_VACT   0x10 /*   1 : VACT   */
#define VSSL_FIELD  0x20 /*   2 : FIELD  */
#define VSSL_VVALID 0x30 /*   3 : VVALID */
#define VSSL_ZERO   0x70 /*   7 : 0      */
#define HSP_LOW     0x00 /* 0 : HS pin output polarity is active low */
#define HSP_HI      0x08 /* 1 : HS pin output polarity is active high.*/
                         /* HS pin output control */
#define HSSL_HACT   0x00 /*   0 : HACT   */
#define HSSL_HSYNC  0x01 /*   1 : HSYNC  */
#define HSSL_DVALID 0x02 /*   2 : DVALID */
#define HSSL_HLOCK  0x03 /*   3 : HLOCK  */
#define HSSL_ASYNCW 0x04 /*   4 : ASYNCW */
#define HSSL_ZERO   0x07 /*   7 : 0      */

/* ACNTL1 */
#define SRESET      0x80 /* resets the device to its default state
                          * but all register content remain unchanged.
                          * This bit is self-resetting.
                          */
#define ACNTL1_PDN_MASK 0x0e
#define CLK_PDN         0x08 /* system clock power down */
#define Y_PDN           0x04 /* Luma ADC power down */
#define C_PDN           0x02 /* Chroma ADC power down */

/* ACNTL2 */
#define ACNTL2_PDN_MASK 0x40
#define PLL_PDN         0x40 /* PLL power down */

/* VBICNTL */

/* RTSEL : control the real time signal output from the MPOUT pin */
#define RTSEL_MASK  0x07
#define RTSEL_VLOSS 0x00 /* 0000 = Video loss */
#define RTSEL_HLOCK 0x01 /* 0001 = H-lock */
#define RTSEL_SLOCK 0x02 /* 0010 = S-lock */
#define RTSEL_VLOCK 0x03 /* 0011 = V-lock */
#define RTSEL_MONO  0x04 /* 0100 = MONO */
#define RTSEL_DET50 0x05 /* 0101 = DET50 */
#define RTSEL_FIELD 0x06 /* 0110 = FIELD */
#define RTSEL_RTCO  0x07 /* 0111 = RTCO ( Real Time Control ) */

/* HSYNC start and end are constant for now */
#define HSYNC_START     0x0260
#define HSYNC_END       0x0300

/*
 * structure
 */

struct regval_list {
        unsigned char reg_num;
        unsigned char value;
};

struct tw9910_scale_ctrl {
        char           *name;
        unsigned short  width;
        unsigned short  height;
        u16             hscale;
        u16             vscale;
};

struct tw9910_priv {
        struct v4l2_subdev              subdev;
        struct v4l2_clk                 *clk;
        struct tw9910_video_info        *info;
        const struct tw9910_scale_ctrl  *scale;
        v4l2_std_id                     norm;
        u32                             revision;
};

static const struct tw9910_scale_ctrl tw9910_ntsc_scales[] = {
        {
                .name   = "NTSC SQ",
                .width  = 640,
                .height = 480,
                .hscale = 0x0100,
                .vscale = 0x0100,
        },
        {
                .name   = "NTSC CCIR601",
                .width  = 720,
                .height = 480,
                .hscale = 0x0100,
                .vscale = 0x0100,
        },
        {
                .name   = "NTSC SQ (CIF)",
                .width  = 320,
                .height = 240,
                .hscale = 0x0200,
                .vscale = 0x0200,
        },
        {
                .name   = "NTSC CCIR601 (CIF)",
                .width  = 360,
                .height = 240,
                .hscale = 0x0200,
                .vscale = 0x0200,
        },
        {
                .name   = "NTSC SQ (QCIF)",
                .width  = 160,
                .height = 120,
                .hscale = 0x0400,
                .vscale = 0x0400,
        },
        {
                .name   = "NTSC CCIR601 (QCIF)",
                .width  = 180,
                .height = 120,
                .hscale = 0x0400,
                .vscale = 0x0400,
        },
};

static const struct tw9910_scale_ctrl tw9910_pal_scales[] = {
        {
                .name   = "PAL SQ",
                .width  = 768,
                .height = 576,
                .hscale = 0x0100,
                .vscale = 0x0100,
        },
        {
                .name   = "PAL CCIR601",
                .width  = 720,
                .height = 576,
                .hscale = 0x0100,
                .vscale = 0x0100,
        },
        {
                .name   = "PAL SQ (CIF)",
                .width  = 384,
                .height = 288,
                .hscale = 0x0200,
                .vscale = 0x0200,
        },
        {
                .name   = "PAL CCIR601 (CIF)",
                .width  = 360,
                .height = 288,
                .hscale = 0x0200,
                .vscale = 0x0200,
        },
        {
                .name   = "PAL SQ (QCIF)",
                .width  = 192,
                .height = 144,
                .hscale = 0x0400,
                .vscale = 0x0400,
        },
        {
                .name   = "PAL CCIR601 (QCIF)",
                .width  = 180,
                .height = 144,
                .hscale = 0x0400,
                .vscale = 0x0400,
        },
};

/*
 * general function
 */
static struct tw9910_priv *to_tw9910(const struct i2c_client *client)
{
        return container_of(i2c_get_clientdata(client), struct tw9910_priv,
                            subdev);
}

static int tw9910_mask_set(struct i2c_client *client, u8 command,
                           u8 mask, u8 set)
{
        s32 val = i2c_smbus_read_byte_data(client, command);
        if (val < 0)
                return val;

        val &= ~mask;
        val |= set & mask;

        return i2c_smbus_write_byte_data(client, command, val);
}

static int tw9910_set_scale(struct i2c_client *client,
                            const struct tw9910_scale_ctrl *scale)
{
        int ret;

        ret = i2c_smbus_write_byte_data(client, SCALE_HI,
                                        (scale->vscale & 0x0F00) >> 4 |
                                        (scale->hscale & 0x0F00) >> 8);
        if (ret < 0)
                return ret;

        ret = i2c_smbus_write_byte_data(client, HSCALE_LO,
                                        scale->hscale & 0x00FF);
        if (ret < 0)
                return ret;

        ret = i2c_smbus_write_byte_data(client, VSCALE_LO,
                                        scale->vscale & 0x00FF);

        return ret;
}

static int tw9910_set_hsync(struct i2c_client *client)
{
        struct tw9910_priv *priv = to_tw9910(client);
        int ret;

        /* bit 10 - 3 */
        ret = i2c_smbus_write_byte_data(client, HSBEGIN,
                                        (HSYNC_START & 0x07F8) >> 3);
        if (ret < 0)
                return ret;

        /* bit 10 - 3 */
        ret = i2c_smbus_write_byte_data(client, HSEND,
                                        (HSYNC_END & 0x07F8) >> 3);
        if (ret < 0)
                return ret;

        /* So far only revisions 0 and 1 have been seen */
        /* bit 2 - 0 */
        if (1 == priv->revision)
                ret = tw9910_mask_set(client, HSLOWCTL, 0x77,
                                      (HSYNC_START & 0x0007) << 4 |
                                      (HSYNC_END   & 0x0007));

        return ret;
}

static void tw9910_reset(struct i2c_client *client)
{
        tw9910_mask_set(client, ACNTL1, SRESET, SRESET);
        msleep(1);
}

static int tw9910_power(struct i2c_client *client, int enable)
{
        int ret;
        u8 acntl1;
        u8 acntl2;

        if (enable) {
                acntl1 = 0;
                acntl2 = 0;
        } else {
                acntl1 = CLK_PDN | Y_PDN | C_PDN;
                acntl2 = PLL_PDN;
        }

        ret = tw9910_mask_set(client, ACNTL1, ACNTL1_PDN_MASK, acntl1);
        if (ret < 0)
                return ret;

        return tw9910_mask_set(client, ACNTL2, ACNTL2_PDN_MASK, acntl2);
}

static const struct tw9910_scale_ctrl *tw9910_select_norm(v4l2_std_id norm,
                                                          u32 width, u32 height)
{
        const struct tw9910_scale_ctrl *scale;
        const struct tw9910_scale_ctrl *ret = NULL;
        __u32 diff = 0xffffffff, tmp;
        int size, i;

        if (norm & V4L2_STD_NTSC) {
                scale = tw9910_ntsc_scales;
                size = ARRAY_SIZE(tw9910_ntsc_scales);
        } else if (norm & V4L2_STD_PAL) {
                scale = tw9910_pal_scales;
                size = ARRAY_SIZE(tw9910_pal_scales);
        } else {
                return NULL;
        }

        for (i = 0; i < size; i++) {
                tmp = abs(width - scale[i].width) +
                        abs(height - scale[i].height);
                if (tmp < diff) {
                        diff = tmp;
                        ret = scale + i;
                }
        }

        return ret;
}

/*
 * subdevice operations
 */
static int tw9910_s_stream(struct v4l2_subdev *sd, int enable)
{
        struct i2c_client *client = v4l2_get_subdevdata(sd);
        struct tw9910_priv *priv = to_tw9910(client);
        u8 val;
        int ret;

        if (!enable) {
                switch (priv->revision) {
                case 0:
                        val = OEN_TRI_SEL_ALL_OFF_r0;
                        break;
                case 1:
                        val = OEN_TRI_SEL_ALL_OFF_r1;
                        break;
                default:
                        dev_err(&client->dev, "un-supported revision\n");
                        return -EINVAL;
                }
        } else {
                val = OEN_TRI_SEL_ALL_ON;

                if (!priv->scale) {
                        dev_err(&client->dev, "norm select error\n");
                        return -EPERM;
                }

                dev_dbg(&client->dev, "%s %dx%d\n",
                        priv->scale->name,
                        priv->scale->width,
                        priv->scale->height);
        }

        ret = tw9910_mask_set(client, OPFORM, OEN_TRI_SEL_MASK, val);
        if (ret < 0)
                return ret;

        return tw9910_power(client, enable);
}

static int tw9910_g_std(struct v4l2_subdev *sd, v4l2_std_id *norm)
{
        struct i2c_client *client = v4l2_get_subdevdata(sd);
        struct tw9910_priv *priv = to_tw9910(client);

        *norm = priv->norm;

        return 0;
}

static int tw9910_s_std(struct v4l2_subdev *sd, v4l2_std_id norm)
{
        struct i2c_client *client = v4l2_get_subdevdata(sd);
        struct tw9910_priv *priv = to_tw9910(client);
        const unsigned hact = 720;
        const unsigned hdelay = 15;
        unsigned vact;
        unsigned vdelay;
        int ret;

        if (!(norm & (V4L2_STD_NTSC | V4L2_STD_PAL)))
                return -EINVAL;

        priv->norm = norm;
        if (norm & V4L2_STD_525_60) {
                vact = 240;
                vdelay = 18;
                ret = tw9910_mask_set(client, VVBI, 0x10, 0x10);
        } else {
                vact = 288;
                vdelay = 24;
                ret = tw9910_mask_set(client, VVBI, 0x10, 0x00);
        }
        if (!ret)
                ret = i2c_smbus_write_byte_data(client, CROP_HI,
                        ((vdelay >> 2) & 0xc0) |
                        ((vact >> 4) & 0x30) |
                        ((hdelay >> 6) & 0x0c) |
                        ((hact >> 8) & 0x03));
        if (!ret)
                ret = i2c_smbus_write_byte_data(client, VDELAY_LO,
                        vdelay & 0xff);
        if (!ret)
                ret = i2c_smbus_write_byte_data(client, VACTIVE_LO,
                        vact & 0xff);

        return ret;
}

#ifdef CONFIG_VIDEO_ADV_DEBUG
static int tw9910_g_register(struct v4l2_subdev *sd,
                             struct v4l2_dbg_register *reg)
{
        struct i2c_client *client = v4l2_get_subdevdata(sd);
        int ret;

        if (reg->reg > 0xff)
                return -EINVAL;

        reg->size = 1;
        ret = i2c_smbus_read_byte_data(client, reg->reg);
        if (ret < 0)
                return ret;

        /*
         * ret      = int
         * reg->val = __u64
         */
        reg->val = (__u64)ret;

        return 0;
}

static int tw9910_s_register(struct v4l2_subdev *sd,
                             const struct v4l2_dbg_register *reg)
{
        struct i2c_client *client = v4l2_get_subdevdata(sd);

        if (reg->reg > 0xff ||
            reg->val > 0xff)
                return -EINVAL;

        return i2c_smbus_write_byte_data(client, reg->reg, reg->val);
}
#endif

static int tw9910_s_power(struct v4l2_subdev *sd, int on)
{
        struct i2c_client *client = v4l2_get_subdevdata(sd);
        struct soc_camera_subdev_desc *ssdd = soc_camera_i2c_to_desc(client);
        struct tw9910_priv *priv = to_tw9910(client);

        return soc_camera_set_power(&client->dev, ssdd, priv->clk, on);
}

static int tw9910_set_frame(struct v4l2_subdev *sd, u32 *width, u32 *height)
{
        struct i2c_client *client = v4l2_get_subdevdata(sd);
        struct tw9910_priv *priv = to_tw9910(client);
        int ret = -EINVAL;
        u8 val;

        /*
         * select suitable norm
         */
        priv->scale = tw9910_select_norm(priv->norm, *width, *height);
        if (!priv->scale)
                goto tw9910_set_fmt_error;

        /*
         * reset hardware
         */
        tw9910_reset(client);

        /*
         * set bus width
         */
        val = 0x00;
        if (SOCAM_DATAWIDTH_16 == priv->info->buswidth)
                val = LEN;

        ret = tw9910_mask_set(client, OPFORM, LEN, val);
        if (ret < 0)
                goto tw9910_set_fmt_error;

        /*
         * select MPOUT behavior
         */
        switch (priv->info->mpout) {
        case TW9910_MPO_VLOSS:
                val = RTSEL_VLOSS; break;
        case TW9910_MPO_HLOCK:
                val = RTSEL_HLOCK; break;
        case TW9910_MPO_SLOCK:
                val = RTSEL_SLOCK; break;
        case TW9910_MPO_VLOCK:
                val = RTSEL_VLOCK; break;
        case TW9910_MPO_MONO:
                val = RTSEL_MONO;  break;
        case TW9910_MPO_DET50:
                val = RTSEL_DET50; break;
        case TW9910_MPO_FIELD:
                val = RTSEL_FIELD; break;
        case TW9910_MPO_RTCO:
                val = RTSEL_RTCO;  break;
        default:
                val = 0;
        }

        ret = tw9910_mask_set(client, VBICNTL, RTSEL_MASK, val);
        if (ret < 0)
                goto tw9910_set_fmt_error;

        /*
         * set scale
         */
        ret = tw9910_set_scale(client, priv->scale);
        if (ret < 0)
                goto tw9910_set_fmt_error;

        /*
         * set hsync
         */
        ret = tw9910_set_hsync(client);
        if (ret < 0)
                goto tw9910_set_fmt_error;

        *width = priv->scale->width;
        *height = priv->scale->height;

        return ret;

tw9910_set_fmt_error:

        tw9910_reset(client);
        priv->scale = NULL;

        return ret;
}

static int tw9910_get_selection(struct v4l2_subdev *sd,
                struct v4l2_subdev_pad_config *cfg,
                struct v4l2_subdev_selection *sel)
{
        struct i2c_client *client = v4l2_get_subdevdata(sd);
        struct tw9910_priv *priv = to_tw9910(client);

        if (sel->which != V4L2_SUBDEV_FORMAT_ACTIVE)
                return -EINVAL;
        /* Only CROP, CROP_DEFAULT and CROP_BOUNDS are supported */
        if (sel->target > V4L2_SEL_TGT_CROP_BOUNDS)
                return -EINVAL;

        sel->r.left     = 0;
        sel->r.top      = 0;
        if (priv->norm & V4L2_STD_NTSC) {
                sel->r.width    = 640;
                sel->r.height   = 480;
        } else {
                sel->r.width    = 768;
                sel->r.height   = 576;
        }
        return 0;
}

static int tw9910_get_fmt(struct v4l2_subdev *sd,
                struct v4l2_subdev_pad_config *cfg,
                struct v4l2_subdev_format *format)
{
        struct v4l2_mbus_framefmt *mf = &format->format;
        struct i2c_client *client = v4l2_get_subdevdata(sd);
        struct tw9910_priv *priv = to_tw9910(client);

        if (format->pad)
                return -EINVAL;

        if (!priv->scale) {
                priv->scale = tw9910_select_norm(priv->norm, 640, 480);
                if (!priv->scale)
                        return -EINVAL;
        }

        mf->width       = priv->scale->width;
        mf->height      = priv->scale->height;
        mf->code        = MEDIA_BUS_FMT_UYVY8_2X8;
        mf->colorspace  = V4L2_COLORSPACE_SMPTE170M;
        mf->field       = V4L2_FIELD_INTERLACED_BT;

        return 0;
}

static int tw9910_s_fmt(struct v4l2_subdev *sd,
                        struct v4l2_mbus_framefmt *mf)
{
        u32 width = mf->width, height = mf->height;
        int ret;

        WARN_ON(mf->field != V4L2_FIELD_ANY &&
                mf->field != V4L2_FIELD_INTERLACED_BT);

        /*
         * check color format
         */
        if (mf->code != MEDIA_BUS_FMT_UYVY8_2X8)
                return -EINVAL;

        mf->colorspace = V4L2_COLORSPACE_SMPTE170M;

        ret = tw9910_set_frame(sd, &width, &height);
        if (!ret) {
                mf->width       = width;
                mf->height      = height;
        }
        return ret;
}

static int tw9910_set_fmt(struct v4l2_subdev *sd,
                struct v4l2_subdev_pad_config *cfg,
                struct v4l2_subdev_format *format)
{
        struct v4l2_mbus_framefmt *mf = &format->format;
        struct i2c_client *client = v4l2_get_subdevdata(sd);
        struct tw9910_priv *priv = to_tw9910(client);
        const struct tw9910_scale_ctrl *scale;

        if (format->pad)
                return -EINVAL;

        if (V4L2_FIELD_ANY == mf->field) {
                mf->field = V4L2_FIELD_INTERLACED_BT;
        } else if (V4L2_FIELD_INTERLACED_BT != mf->field) {
                dev_err(&client->dev, "Field type %d invalid.\n", mf->field);
                return -EINVAL;
        }

        mf->code = MEDIA_BUS_FMT_UYVY8_2X8;
        mf->colorspace = V4L2_COLORSPACE_SMPTE170M;

        /*
         * select suitable norm
         */
        scale = tw9910_select_norm(priv->norm, mf->width, mf->height);
        if (!scale)
                return -EINVAL;

        mf->width       = scale->width;
        mf->height      = scale->height;

        if (format->which == V4L2_SUBDEV_FORMAT_ACTIVE)
                return tw9910_s_fmt(sd, mf);
        cfg->try_fmt = *mf;
        return 0;
}

static int tw9910_video_probe(struct i2c_client *client)
{
        struct tw9910_priv *priv = to_tw9910(client);
        s32 id;
        int ret;

        /*
         * tw9910 only use 8 or 16 bit bus width
         */
        if (SOCAM_DATAWIDTH_16 != priv->info->buswidth &&
            SOCAM_DATAWIDTH_8  != priv->info->buswidth) {
                dev_err(&client->dev, "bus width error\n");
                return -ENODEV;
        }

        ret = tw9910_s_power(&priv->subdev, 1);
        if (ret < 0)
                return ret;

        /*
         * check and show Product ID
         * So far only revisions 0 and 1 have been seen
         */
        id = i2c_smbus_read_byte_data(client, ID);
        priv->revision = GET_REV(id);
        id = GET_ID(id);

        if (0x0B != id ||
            0x01 < priv->revision) {
                dev_err(&client->dev,
                        "Product ID error %x:%x\n",
                        id, priv->revision);
                ret = -ENODEV;
                goto done;
        }

        dev_info(&client->dev,
                 "tw9910 Product ID %0x:%0x\n", id, priv->revision);

        priv->norm = V4L2_STD_NTSC;
        priv->scale = &tw9910_ntsc_scales[0];

done:
        tw9910_s_power(&priv->subdev, 0);
        return ret;
}

static const struct v4l2_subdev_core_ops tw9910_subdev_core_ops = {
#ifdef CONFIG_VIDEO_ADV_DEBUG
        .g_register     = tw9910_g_register,
        .s_register     = tw9910_s_register,
#endif
        .s_power        = tw9910_s_power,
};

static int tw9910_enum_mbus_code(struct v4l2_subdev *sd,
                struct v4l2_subdev_pad_config *cfg,
                struct v4l2_subdev_mbus_code_enum *code)
{
        if (code->pad || code->index)
                return -EINVAL;

        code->code = MEDIA_BUS_FMT_UYVY8_2X8;
        return 0;
}

static int tw9910_g_mbus_config(struct v4l2_subdev *sd,
                                struct v4l2_mbus_config *cfg)
{
        struct i2c_client *client = v4l2_get_subdevdata(sd);
        struct soc_camera_subdev_desc *ssdd = soc_camera_i2c_to_desc(client);

        cfg->flags = V4L2_MBUS_PCLK_SAMPLE_RISING | V4L2_MBUS_MASTER |
                V4L2_MBUS_VSYNC_ACTIVE_HIGH | V4L2_MBUS_VSYNC_ACTIVE_LOW |
                V4L2_MBUS_HSYNC_ACTIVE_HIGH | V4L2_MBUS_HSYNC_ACTIVE_LOW |
                V4L2_MBUS_DATA_ACTIVE_HIGH;
        cfg->type = V4L2_MBUS_PARALLEL;
        cfg->flags = soc_camera_apply_board_flags(ssdd, cfg);

        return 0;
}

static int tw9910_s_mbus_config(struct v4l2_subdev *sd,
                                const struct v4l2_mbus_config *cfg)
{
        struct i2c_client *client = v4l2_get_subdevdata(sd);
        struct soc_camera_subdev_desc *ssdd = soc_camera_i2c_to_desc(client);
        u8 val = VSSL_VVALID | HSSL_DVALID;
        unsigned long flags = soc_camera_apply_board_flags(ssdd, cfg);

        /*
         * set OUTCTR1
         *
         * We use VVALID and DVALID signals to control VSYNC and HSYNC
         * outputs, in this mode their polarity is inverted.
         */
        if (flags & V4L2_MBUS_HSYNC_ACTIVE_LOW)
                val |= HSP_HI;

        if (flags & V4L2_MBUS_VSYNC_ACTIVE_LOW)
                val |= VSP_HI;

        return i2c_smbus_write_byte_data(client, OUTCTR1, val);
}

static int tw9910_g_tvnorms(struct v4l2_subdev *sd, v4l2_std_id *norm)
{
        *norm = V4L2_STD_NTSC | V4L2_STD_PAL;
        return 0;
}

static const struct v4l2_subdev_video_ops tw9910_subdev_video_ops = {
        .s_std          = tw9910_s_std,
        .g_std          = tw9910_g_std,
        .s_stream       = tw9910_s_stream,
        .g_mbus_config  = tw9910_g_mbus_config,
        .s_mbus_config  = tw9910_s_mbus_config,
        .g_tvnorms      = tw9910_g_tvnorms,
};

static const struct v4l2_subdev_pad_ops tw9910_subdev_pad_ops = {
        .enum_mbus_code = tw9910_enum_mbus_code,
        .get_selection  = tw9910_get_selection,
        .get_fmt        = tw9910_get_fmt,
        .set_fmt        = tw9910_set_fmt,
};

static const struct v4l2_subdev_ops tw9910_subdev_ops = {
        .core   = &tw9910_subdev_core_ops,
        .video  = &tw9910_subdev_video_ops,
        .pad    = &tw9910_subdev_pad_ops,
};

/*
 * i2c_driver function
 */

static int tw9910_probe(struct i2c_client *client,
                        const struct i2c_device_id *did)

{
        struct tw9910_priv              *priv;
        struct tw9910_video_info        *info;
        struct i2c_adapter              *adapter =
                to_i2c_adapter(client->dev.parent);
        struct soc_camera_subdev_desc   *ssdd = soc_camera_i2c_to_desc(client);
        int ret;

        if (!ssdd || !ssdd->drv_priv) {
                dev_err(&client->dev, "TW9910: missing platform data!\n");
                return -EINVAL;
        }

        info = ssdd->drv_priv;

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

        priv = devm_kzalloc(&client->dev, sizeof(*priv), GFP_KERNEL);
        if (!priv)
                return -ENOMEM;

        priv->info   = info;

        v4l2_i2c_subdev_init(&priv->subdev, client, &tw9910_subdev_ops);

        priv->clk = v4l2_clk_get(&client->dev, "mclk");
        if (IS_ERR(priv->clk))
                return PTR_ERR(priv->clk);

        ret = tw9910_video_probe(client);
        if (ret < 0)
                v4l2_clk_put(priv->clk);

        return ret;
}

static int tw9910_remove(struct i2c_client *client)
{
        struct tw9910_priv *priv = to_tw9910(client);
        v4l2_clk_put(priv->clk);
        return 0;
}

static const struct i2c_device_id tw9910_id[] = {
        { "tw9910", 0 },
        { }
};
MODULE_DEVICE_TABLE(i2c, tw9910_id);

static struct i2c_driver tw9910_i2c_driver = {
        .driver = {
                .name = "tw9910",
        },
        .probe    = tw9910_probe,
        .remove   = tw9910_remove,
        .id_table = tw9910_id,
};

module_i2c_driver(tw9910_i2c_driver);

MODULE_DESCRIPTION("SoC Camera driver for tw9910");
MODULE_AUTHOR("Kuninori Morimoto");
MODULE_LICENSE("GPL v2");