/*
 * ToupTek UCMOS / AmScope MU series camera driver
 * TODO: contrast with ScopeTek / AmScope MDC cameras
 *
 * Copyright (C) 2012-2014 John McMaster <JohnDMcMaster@gmail.com>
 *
 * Special thanks to Bushing for helping with the decrypt algorithm and
 * Sean O'Sullivan / the Rensselaer Center for Open Source
 * Software (RCOS) for helping me learn kernel development
 *
 * 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
 * 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.
 */

#include "gspca.h"

#define MODULE_NAME "touptek"

MODULE_AUTHOR("John McMaster");
MODULE_DESCRIPTION("ToupTek UCMOS / Amscope MU microscope camera driver");
MODULE_LICENSE("GPL");

/*
 * Exposure reg is linear with exposure time
 * Exposure (sec), E (reg)
 * 0.000400, 0x0002
 * 0.001000, 0x0005
 * 0.005000, 0x0019
 * 0.020000, 0x0064
 * 0.080000, 0x0190
 * 0.400000, 0x07D0
 * 1.000000, 0x1388
 * 2.000000, 0x2710
 *
 * Three gain stages
 * 0x1000: master channel enable bit
 * 0x007F: low gain bits
 * 0x0080: medium gain bit
 * 0x0100: high gain bit
 * gain = enable * (1 + regH) * (1 + regM) * z * regL
 *
 * Gain implementation
 * Want to do something similar to mt9v011.c's set_balance
 *
 * Gain does not vary with resolution (checked 640x480 vs 1600x1200)
 *
 * Constant derivation:
 *
 * Raw data:
 * Gain,   GTOP,   B,     R,      GBOT
 * 1.00,   0x105C, 0x1068, 0x10C8, 0x105C
 * 1.20,   0x106E, 0x107E, 0x10D6, 0x106E
 * 1.40,   0x10C0, 0x10CA, 0x10E5, 0x10C0
 * 1.60,   0x10C9, 0x10D4, 0x10F3, 0x10C9
 * 1.80,   0x10D2, 0x10DE, 0x11C1, 0x10D2
 * 2.00,   0x10DC, 0x10E9, 0x11C8, 0x10DC
 * 2.20,   0x10E5, 0x10F3, 0x11CF, 0x10E5
 * 2.40,   0x10EE, 0x10FE, 0x11D7, 0x10EE
 * 2.60,   0x10F7, 0x11C4, 0x11DE, 0x10F7
 * 2.80,   0x11C0, 0x11CA, 0x11E5, 0x11C0
 * 3.00,   0x11C5, 0x11CF, 0x11ED, 0x11C5
 *
 * zR = 0.0069605943152454778
 *      about 3/431 = 0.0069605568445475635
 * zB = 0.0095695970695970703
 *      about 6/627 = 0.0095693779904306216
 * zG = 0.010889328063241107
 *      about 6/551 = 0.010889292196007259
 * about 10 bits for constant + 7 bits for value => at least 17 bit
 * intermediate with 32 bit ints should be fine for overflow etc
 * Essentially gains are in range 0-0x001FF
 *
 * However, V4L expects a main gain channel + R and B balance
 * To keep things simple for now saturate the values of balance is too high/low
 * This isn't really ideal but easy way to fit the Linux model
 *
 * Converted using gain model turns out to be quite linear:
 * Gain, GTOP, B, R, GBOT
 * 1.00, 92, 104, 144, 92
 * 1.20, 110, 126, 172, 110
 * 1.40, 128, 148, 202, 128
 * 1.60, 146, 168, 230, 146
 * 1.80, 164, 188, 260, 164
 * 2.00, 184, 210, 288, 184
 * 2.20, 202, 230, 316, 202
 * 2.40, 220, 252, 348, 220
 * 2.60, 238, 272, 376, 238
 * 2.80, 256, 296, 404, 256
 * 3.00, 276, 316, 436, 276
 *
 * Maximum gain is 0x7FF * 2 * 2 => 0x1FFC (8188)
 * or about 13 effective bits of gain
 * The highest the commercial driver goes in my setup 436
 * However, because could *maybe* damage circuits
 * limit the gain until have a reason to go higher
 * Solution: gain clipped and warning emitted
 */
#define GAIN_MAX                511

/* Frame sync is a short read */
#define BULK_SIZE               0x4000

/* MT9E001 reg names to give a rough approximation */
#define REG_COARSE_INTEGRATION_TIME_    0x3012
#define REG_GROUPED_PARAMETER_HOLD_     0x3022
#define REG_MODE_SELECT                 0x0100
#define REG_OP_SYS_CLK_DIV              0x030A
#define REG_VT_SYS_CLK_DIV              0x0302
#define REG_PRE_PLL_CLK_DIV             0x0304
#define REG_VT_PIX_CLK_DIV              0x0300
#define REG_OP_PIX_CLK_DIV              0x0308
#define REG_PLL_MULTIPLIER              0x0306
#define REG_COARSE_INTEGRATION_TIME_    0x3012
#define REG_FRAME_LENGTH_LINES          0x0340
#define REG_FRAME_LENGTH_LINES_         0x300A
#define REG_GREEN1_GAIN                 0x3056
#define REG_GREEN2_GAIN                 0x305C
#define REG_GROUPED_PARAMETER_HOLD      0x0104
#define REG_LINE_LENGTH_PCK_            0x300C
#define REG_MODE_SELECT                 0x0100
#define REG_PLL_MULTIPLIER              0x0306
#define REG_READ_MODE                   0x3040
#define REG_BLUE_GAIN                   0x3058
#define REG_RED_GAIN                    0x305A
#define REG_RESET_REGISTER              0x301A
#define REG_SCALE_M                     0x0404
#define REG_SCALING_MODE                0x0400
#define REG_SOFTWARE_RESET              0x0103
#define REG_X_ADDR_END                  0x0348
#define REG_X_ADDR_START                0x0344
#define REG_X_ADDR_START                0x0344
#define REG_X_OUTPUT_SIZE               0x034C
#define REG_Y_ADDR_END                  0x034A
#define REG_Y_ADDR_START                0x0346
#define REG_Y_OUTPUT_SIZE               0x034E


/* specific webcam descriptor */
struct sd {
        struct gspca_dev gspca_dev;     /* !! must be the first item */
        /* How many bytes this frame */
        unsigned int this_f;

        /*
        Device has separate gains for each Bayer quadrant
        V4L supports master gain which is referenced to G1/G2 and supplies
        individual balance controls for R/B
        */
        struct v4l2_ctrl *blue;
        struct v4l2_ctrl *red;
};

/* Used to simplify reg write error handling */
struct cmd {
        u16 value;
        u16 index;
};

static const struct v4l2_pix_format vga_mode[] = {
        {800, 600,
                V4L2_PIX_FMT_SGRBG8,
                V4L2_FIELD_NONE,
                .bytesperline = 800,
                .sizeimage = 800 * 600,
                .colorspace = V4L2_COLORSPACE_SRGB},
        {1600, 1200,
                V4L2_PIX_FMT_SGRBG8,
                V4L2_FIELD_NONE,
                .bytesperline = 1600,
                .sizeimage = 1600 * 1200,
                .colorspace = V4L2_COLORSPACE_SRGB},
        {3264, 2448,
                V4L2_PIX_FMT_SGRBG8,
                V4L2_FIELD_NONE,
                .bytesperline = 3264,
                .sizeimage = 3264 * 2448,
                .colorspace = V4L2_COLORSPACE_SRGB},
};

/*
 * As theres no known frame sync, the only way to keep synced is to try hard
 * to never miss any packets
 */
#if MAX_NURBS < 4
#error "Not enough URBs in the gspca table"
#endif

static int val_reply(struct gspca_dev *gspca_dev, const char *reply, int rc)
{
        if (rc < 0) {
                PERR("reply has error %d", rc);
                return -EIO;
        }
        if (rc != 1) {
                PERR("Bad reply size %d", rc);
                return -EIO;
        }
        if (reply[0] != 0x08) {
                PERR("Bad reply 0x%02x", (int)reply[0]);
                return -EIO;
        }
        return 0;
}

static void reg_w(struct gspca_dev *gspca_dev, u16 value, u16 index)
{
        char *buff = gspca_dev->usb_buf;
        int rc;

        PDEBUG(D_USBO,
                "reg_w bReq=0x0B, bReqT=0xC0, wVal=0x%04X, wInd=0x%04X\n",
                value, index);
        rc = usb_control_msg(gspca_dev->dev, usb_rcvctrlpipe(gspca_dev->dev, 0),
                0x0B, 0xC0, value, index, buff, 1, 500);
        PDEBUG(D_USBO, "rc=%d, ret={0x%02x}", rc, (int)buff[0]);
        if (rc < 0) {
                PERR("Failed reg_w(0x0B, 0xC0, 0x%04X, 0x%04X) w/ rc %d\n",
                        value, index, rc);
                gspca_dev->usb_err = rc;
                return;
        }
        if (val_reply(gspca_dev, buff, rc)) {
                PERR("Bad reply to reg_w(0x0B, 0xC0, 0x%04X, 0x%04X\n",
                        value, index);
                gspca_dev->usb_err = -EIO;
        }
}

static void reg_w_buf(struct gspca_dev *gspca_dev,
                const struct cmd *p, int l)
{
        do {
                reg_w(gspca_dev, p->value, p->index);
                p++;
        } while (--l > 0);
}

static void setexposure(struct gspca_dev *gspca_dev, s32 val)
{
        u16 value;
        unsigned int w = gspca_dev->pixfmt.width;

        if (w == 800)
                value = val * 5;
        else if (w == 1600)
                value = val * 3;
        else if (w == 3264)
                value = val * 3 / 2;
        else {
                PERR("Invalid width %u\n", w);
                gspca_dev->usb_err = -EINVAL;
                return;
        }
        PDEBUG(D_STREAM, "exposure: 0x%04X ms\n", value);
        /* Wonder if theres a good reason for sending it twice */
        /* probably not but leave it in because...why not */
        reg_w(gspca_dev, value, REG_COARSE_INTEGRATION_TIME_);
        reg_w(gspca_dev, value, REG_COARSE_INTEGRATION_TIME_);
}

static int gainify(int in)
{
        /*
         * TODO: check if there are any issues with corner cases
         * 0x000 (0):0x07F (127): regL
         * 0x080 (128) - 0x0FF (255): regM, regL
         * 0x100 (256) - max: regH, regM, regL
         */
        if (in <= 0x7F)
                return 0x1000 | in;
        else if (in <= 0xFF)
                return 0x1080 | in / 2;
        else
                return 0x1180 | in / 4;
}

static void setggain(struct gspca_dev *gspca_dev, u16 global_gain)
{
        u16 normalized;

        normalized = gainify(global_gain);
        PDEBUG(D_STREAM, "gain G1/G2 (0x%04X): 0x%04X (src 0x%04X)\n",
                 REG_GREEN1_GAIN,
                 normalized, global_gain);

        reg_w(gspca_dev, normalized, REG_GREEN1_GAIN);
        reg_w(gspca_dev, normalized, REG_GREEN2_GAIN);
}

static void setbgain(struct gspca_dev *gspca_dev,
                u16 gain, u16 global_gain)
{
        u16 normalized;

        normalized = global_gain +
                ((u32)global_gain) * gain / GAIN_MAX;
        if (normalized > GAIN_MAX) {
                PDEBUG(D_STREAM, "Truncating blue 0x%04X w/ value 0x%04X\n",
                         GAIN_MAX, normalized);
                normalized = GAIN_MAX;
        }
        normalized = gainify(normalized);
        PDEBUG(D_STREAM, "gain B (0x%04X): 0x%04X w/ source 0x%04X\n",
                 REG_BLUE_GAIN, normalized, gain);

        reg_w(gspca_dev, normalized, REG_BLUE_GAIN);
}

static void setrgain(struct gspca_dev *gspca_dev,
                u16 gain, u16 global_gain)
{
        u16 normalized;

        normalized = global_gain +
                ((u32)global_gain) * gain / GAIN_MAX;
        if (normalized > GAIN_MAX) {
                PDEBUG(D_STREAM, "Truncating gain 0x%04X w/ value 0x%04X\n",
                         GAIN_MAX, normalized);
                normalized = GAIN_MAX;
        }
        normalized = gainify(normalized);
        PDEBUG(D_STREAM, "gain R (0x%04X): 0x%04X w / source 0x%04X\n",
                 REG_RED_GAIN, normalized, gain);

        reg_w(gspca_dev, normalized, REG_RED_GAIN);
}

static void configure_wh(struct gspca_dev *gspca_dev)
{
        unsigned int w = gspca_dev->pixfmt.width;

        PDEBUG(D_STREAM, "configure_wh\n");

        if (w == 800) {
                static const struct cmd reg_init_res[] = {
                        {0x0060, REG_X_ADDR_START},
                        {0x0CD9, REG_X_ADDR_END},
                        {0x0036, REG_Y_ADDR_START},
                        {0x098F, REG_Y_ADDR_END},
                        {0x07C7, REG_READ_MODE},
                };

                reg_w_buf(gspca_dev,
                               reg_init_res, ARRAY_SIZE(reg_init_res));
        } else if (w == 1600) {
                static const struct cmd reg_init_res[] = {
                        {0x009C, REG_X_ADDR_START},
                        {0x0D19, REG_X_ADDR_END},
                        {0x0068, REG_Y_ADDR_START},
                        {0x09C5, REG_Y_ADDR_END},
                        {0x06C3, REG_READ_MODE},
                };

                reg_w_buf(gspca_dev,
                               reg_init_res, ARRAY_SIZE(reg_init_res));
        } else if (w == 3264) {
                static const struct cmd reg_init_res[] = {
                        {0x00E8, REG_X_ADDR_START},
                        {0x0DA7, REG_X_ADDR_END},
                        {0x009E, REG_Y_ADDR_START},
                        {0x0A2D, REG_Y_ADDR_END},
                        {0x0241, REG_READ_MODE},
                };

                reg_w_buf(gspca_dev,
                               reg_init_res, ARRAY_SIZE(reg_init_res));
        } else {
                PERR("bad width %u\n", w);
                gspca_dev->usb_err = -EINVAL;
                return;
        }

        reg_w(gspca_dev, 0x0000, REG_SCALING_MODE);
        reg_w(gspca_dev, 0x0010, REG_SCALE_M);
        reg_w(gspca_dev, w, REG_X_OUTPUT_SIZE);
        reg_w(gspca_dev, gspca_dev->pixfmt.height, REG_Y_OUTPUT_SIZE);

        if (w == 800) {
                reg_w(gspca_dev, 0x0384, REG_FRAME_LENGTH_LINES_);
                reg_w(gspca_dev, 0x0960, REG_LINE_LENGTH_PCK_);
        } else if (w == 1600) {
                reg_w(gspca_dev, 0x0640, REG_FRAME_LENGTH_LINES_);
                reg_w(gspca_dev, 0x0FA0, REG_LINE_LENGTH_PCK_);
        } else if (w == 3264) {
                reg_w(gspca_dev, 0x0B4B, REG_FRAME_LENGTH_LINES_);
                reg_w(gspca_dev, 0x1F40, REG_LINE_LENGTH_PCK_);
        } else {
                PERR("bad width %u\n", w);
                gspca_dev->usb_err = -EINVAL;
                return;
        }
}

/* Packets that were encrypted, no idea if the grouping is significant */
static void configure_encrypted(struct gspca_dev *gspca_dev)
{
        static const struct cmd reg_init_begin[] = {
                {0x0100, REG_SOFTWARE_RESET},
                {0x0000, REG_MODE_SELECT},
                {0x0100, REG_GROUPED_PARAMETER_HOLD},
                {0x0004, REG_VT_PIX_CLK_DIV},
                {0x0001, REG_VT_SYS_CLK_DIV},
                {0x0008, REG_OP_PIX_CLK_DIV},
                {0x0001, REG_OP_SYS_CLK_DIV},
                {0x0004, REG_PRE_PLL_CLK_DIV},
                {0x0040, REG_PLL_MULTIPLIER},
                {0x0000, REG_GROUPED_PARAMETER_HOLD},
                {0x0100, REG_GROUPED_PARAMETER_HOLD},
        };
        static const struct cmd reg_init_end[] = {
                {0x0000, REG_GROUPED_PARAMETER_HOLD},
                {0x0301, 0x31AE},
                {0x0805, 0x3064},
                {0x0071, 0x3170},
                {0x10DE, REG_RESET_REGISTER},
                {0x0000, REG_MODE_SELECT},
                {0x0010, REG_PLL_MULTIPLIER},
                {0x0100, REG_MODE_SELECT},
        };

        PDEBUG(D_STREAM, "Encrypted begin, w = %u\n", gspca_dev->pixfmt.width);
        reg_w_buf(gspca_dev, reg_init_begin, ARRAY_SIZE(reg_init_begin));
        configure_wh(gspca_dev);
        reg_w_buf(gspca_dev, reg_init_end, ARRAY_SIZE(reg_init_end));
        reg_w(gspca_dev, 0x0100, REG_GROUPED_PARAMETER_HOLD);
        reg_w(gspca_dev, 0x0000, REG_GROUPED_PARAMETER_HOLD);

        PDEBUG(D_STREAM, "Encrypted end\n");
}

static int configure(struct gspca_dev *gspca_dev)
{
        int rc;
        char *buff = gspca_dev->usb_buf;

        PDEBUG(D_STREAM, "configure()\n");

        /*
         * First driver sets a sort of encryption key
         * A number of futur requests of this type have wValue and wIndex
         * encrypted as follows:
         * -Compute key = this wValue rotate left by 4 bits
         *      (decrypt.py rotates right because we are decrypting)
         * -Later packets encrypt packets by XOR'ing with key
         *      XOR encrypt/decrypt is symmetrical
         *      wValue, and wIndex are encrypted
         *      bRequest is not and bRequestType is always 0xC0
         *              This allows resyncing if key is unknown?
         * By setting 0 we XOR with 0 and the shifting and XOR drops out
         */
        rc = usb_control_msg(gspca_dev->dev, usb_rcvctrlpipe(gspca_dev->dev, 0),
                             0x16, 0xC0, 0x0000, 0x0000, buff, 2, 500);
        if (val_reply(gspca_dev, buff, rc)) {
                PERR("failed key req");
                return -EIO;
        }

        /*
         * Next does some sort of 2 packet challenge / response
         * evidence suggests its an Atmel I2C crypto part but nobody cares to
         * look
         * (to make sure its not cloned hardware?)
         * Ignore: I want to work with their hardware, not clone it
         * 16 bytes out challenge, requestType: 0x40
         * 16 bytes in response, requestType: 0xC0
         */

        rc = usb_control_msg(gspca_dev->dev, usb_sndctrlpipe(gspca_dev->dev, 0),
                             0x01, 0x40, 0x0001, 0x000F, NULL, 0, 500);
        if (rc < 0) {
                PERR("failed to replay packet 176 w/ rc %d\n", rc);
                return rc;
        }

        rc = usb_control_msg(gspca_dev->dev, usb_sndctrlpipe(gspca_dev->dev, 0),
                             0x01, 0x40, 0x0000, 0x000F, NULL, 0, 500);
        if (rc < 0) {
                PERR("failed to replay packet 178 w/ rc %d\n", rc);
                return rc;
        }

        rc = usb_control_msg(gspca_dev->dev, usb_sndctrlpipe(gspca_dev->dev, 0),
                             0x01, 0x40, 0x0001, 0x000F, NULL, 0, 500);
        if (rc < 0) {
                PERR("failed to replay packet 180 w/ rc %d\n", rc);
                return rc;
        }

        /*
         * Serial number?  Doesn't seem to be required
         * cam1: \xE6\x0D\x00\x00, cam2: \x70\x19\x00\x00
         * rc = usb_control_msg(gspca_dev->dev,
         *                      usb_rcvctrlpipe(gspca_dev->dev, 0),
         *                      0x20, 0xC0, 0x0000, 0x0000, buff, 4, 500);
         */

        /* Large (EEPROM?) read, skip it since no idea what to do with it */
        gspca_dev->usb_err = 0;
        configure_encrypted(gspca_dev);
        if (gspca_dev->usb_err)
                return gspca_dev->usb_err;

        /* Omitted this by accident, does not work without it */
        rc = usb_control_msg(gspca_dev->dev, usb_sndctrlpipe(gspca_dev->dev, 0),
                             0x01, 0x40, 0x0003, 0x000F, NULL, 0, 500);
        if (rc < 0) {
                PERR("failed to replay final packet w/ rc %d\n", rc);
                return rc;
        }

        PDEBUG(D_STREAM, "Configure complete\n");
        return 0;
}

static int sd_config(struct gspca_dev *gspca_dev,
                     const struct usb_device_id *id)
{
        gspca_dev->cam.cam_mode = vga_mode;
        gspca_dev->cam.nmodes = ARRAY_SIZE(vga_mode);

        /* Yes we want URBs and we want them now! */
        gspca_dev->cam.no_urb_create = 0;
        gspca_dev->cam.bulk_nurbs = 4;
        /* Largest size the windows driver uses */
        gspca_dev->cam.bulk_size = BULK_SIZE;
        /* Def need to use bulk transfers */
        gspca_dev->cam.bulk = 1;

        return 0;
}

static int sd_start(struct gspca_dev *gspca_dev)
{
        struct sd *sd = (struct sd *) gspca_dev;
        int rc;

        sd->this_f = 0;

        rc = configure(gspca_dev);
        if (rc < 0) {
                PERR("Failed configure");
                return rc;
        }
        /* First two frames have messed up gains
        Drop them to avoid special cases in user apps? */
        return 0;
}

static void sd_pkt_scan(struct gspca_dev *gspca_dev,
                        u8 *data,       /* isoc packet */
                        int len)        /* iso packet length */
{
        struct sd *sd = (struct sd *) gspca_dev;

        if (len != BULK_SIZE) {
                /* can we finish a frame? */
                if (sd->this_f + len == gspca_dev->pixfmt.sizeimage) {
                        gspca_frame_add(gspca_dev, LAST_PACKET, data, len);
                        PDEBUG(D_FRAM, "finish frame sz %u/%u w/ len %u\n",
                                 sd->this_f, gspca_dev->pixfmt.sizeimage, len);
                /* lost some data, discard the frame */
                } else {
                        gspca_frame_add(gspca_dev, DISCARD_PACKET, NULL, 0);
                        PDEBUG(D_FRAM, "abort frame sz %u/%u w/ len %u\n",
                                 sd->this_f, gspca_dev->pixfmt.sizeimage, len);
                }
                sd->this_f = 0;
        } else {
                if (sd->this_f == 0)
                        gspca_frame_add(gspca_dev, FIRST_PACKET, data, len);
                else
                        gspca_frame_add(gspca_dev, INTER_PACKET, data, len);
                sd->this_f += len;
        }
}

static int sd_init(struct gspca_dev *gspca_dev)
{
        return 0;
}

static int sd_s_ctrl(struct v4l2_ctrl *ctrl)
{
        struct gspca_dev *gspca_dev =
                container_of(ctrl->handler, struct gspca_dev, ctrl_handler);
        struct sd *sd = (struct sd *) gspca_dev;

        gspca_dev->usb_err = 0;

        if (!gspca_dev->streaming)
                return 0;

        switch (ctrl->id) {
        case V4L2_CID_EXPOSURE:
                setexposure(gspca_dev, ctrl->val);
                break;
        case V4L2_CID_GAIN:
                /* gspca_dev->gain automatically updated */
                setggain(gspca_dev, gspca_dev->gain->val);
                break;
        case V4L2_CID_BLUE_BALANCE:
                sd->blue->val = ctrl->val;
                setbgain(gspca_dev, sd->blue->val, gspca_dev->gain->val);
                break;
        case V4L2_CID_RED_BALANCE:
                sd->red->val = ctrl->val;
                setrgain(gspca_dev, sd->red->val, gspca_dev->gain->val);
                break;
        }
        return gspca_dev->usb_err;
}

static const struct v4l2_ctrl_ops sd_ctrl_ops = {
        .s_ctrl = sd_s_ctrl,
};

static int sd_init_controls(struct gspca_dev *gspca_dev)
{
        struct sd *sd = (struct sd *) gspca_dev;
        struct v4l2_ctrl_handler *hdl = &gspca_dev->ctrl_handler;

        gspca_dev->vdev.ctrl_handler = hdl;
        v4l2_ctrl_handler_init(hdl, 4);

        gspca_dev->exposure = v4l2_ctrl_new_std(hdl, &sd_ctrl_ops,
        /* Mostly limited by URB timeouts */
        /* XXX: make dynamic based on frame rate? */
                V4L2_CID_EXPOSURE, 0, 800, 1, 350);
        gspca_dev->gain = v4l2_ctrl_new_std(hdl, &sd_ctrl_ops,
                        V4L2_CID_GAIN, 0, 511, 1, 128);
        sd->blue = v4l2_ctrl_new_std(hdl, &sd_ctrl_ops,
                        V4L2_CID_BLUE_BALANCE, 0, 1023, 1, 80);
        sd->red = v4l2_ctrl_new_std(hdl, &sd_ctrl_ops,
                        V4L2_CID_RED_BALANCE, 0, 1023, 1, 295);

        if (hdl->error) {
                PERR("Could not initialize controls\n");
                return hdl->error;
        }
        return 0;
}

/* sub-driver description */
static const struct sd_desc sd_desc = {
        .name = MODULE_NAME,
        .config = sd_config,
        .init = sd_init,
        .init_controls = sd_init_controls,
        .start = sd_start,
        .pkt_scan = sd_pkt_scan,
};

/* Table of supported USB devices */
static const struct usb_device_id device_table[] = {
        /* Commented out devices should be related */
        /* AS: AmScope, TT: ToupTek */
        /* { USB_DEVICE(0x0547, 0x6035) },  TT UCMOS00350KPA */
        /* { USB_DEVICE(0x0547, 0x6130) },  TT UCMOS01300KPA */
        /* { USB_DEVICE(0x0547, 0x6200) },  TT UCMOS02000KPA */
        /* { USB_DEVICE(0x0547, 0x6310) },  TT UCMOS03100KPA */
        /* { USB_DEVICE(0x0547, 0x6510) },  TT UCMOS05100KPA */
        /* { USB_DEVICE(0x0547, 0x6800) },  TT UCMOS08000KPA */
        /* { USB_DEVICE(0x0547, 0x6801) },  TT UCMOS08000KPB */
        { USB_DEVICE(0x0547, 0x6801) }, /* TT UCMOS08000KPB, AS MU800 */
        /* { USB_DEVICE(0x0547, 0x6900) },  TT UCMOS09000KPA */
        /* { USB_DEVICE(0x0547, 0x6901) },  TT UCMOS09000KPB */
        /* { USB_DEVICE(0x0547, 0x6010) },  TT UCMOS10000KPA */
        /* { USB_DEVICE(0x0547, 0x6014) },  TT UCMOS14000KPA */
        /* { USB_DEVICE(0x0547, 0x6131) },  TT UCMOS01300KMA */
        /* { USB_DEVICE(0x0547, 0x6511) },  TT UCMOS05100KMA */
        /* { USB_DEVICE(0x0547, 0x8080) },  TT UHCCD00800KPA */
        /* { USB_DEVICE(0x0547, 0x8140) },  TT UHCCD01400KPA */
        /* { USB_DEVICE(0x0547, 0x8141) },  TT EXCCD01400KPA */
        /* { USB_DEVICE(0x0547, 0x8200) },  TT UHCCD02000KPA */
        /* { USB_DEVICE(0x0547, 0x8201) },  TT UHCCD02000KPB */
        /* { USB_DEVICE(0x0547, 0x8310) },  TT UHCCD03100KPA */
        /* { USB_DEVICE(0x0547, 0x8500) },  TT UHCCD05000KPA */
        /* { USB_DEVICE(0x0547, 0x8510) },  TT UHCCD05100KPA */
        /* { USB_DEVICE(0x0547, 0x8600) },  TT UHCCD06000KPA */
        /* { USB_DEVICE(0x0547, 0x8800) },  TT UHCCD08000KPA */
        /* { USB_DEVICE(0x0547, 0x8315) },  TT UHCCD03150KPA */
        /* { USB_DEVICE(0x0547, 0x7800) },  TT UHCCD00800KMA */
        /* { USB_DEVICE(0x0547, 0x7140) },  TT UHCCD01400KMA */
        /* { USB_DEVICE(0x0547, 0x7141) },  TT UHCCD01400KMB */
        /* { USB_DEVICE(0x0547, 0x7200) },  TT UHCCD02000KMA */
        /* { USB_DEVICE(0x0547, 0x7315) },  TT UHCCD03150KMA */
        { }
};
MODULE_DEVICE_TABLE(usb, device_table);

static int sd_probe(struct usb_interface *intf,
                    const struct usb_device_id *id)
{
        return gspca_dev_probe(intf, id, &sd_desc, sizeof(struct sd),
                             THIS_MODULE);
}

static struct usb_driver sd_driver = {
        .name = MODULE_NAME,
        .id_table = device_table,
        .probe = sd_probe,
        .disconnect = gspca_disconnect,
#ifdef CONFIG_PM
        .suspend = gspca_suspend,
        .resume = gspca_resume,
#endif
};

static int __init sd_mod_init(void)
{
        int ret;

        ret = usb_register(&sd_driver);
        if (ret < 0)
                return ret;
        return 0;
}
static void __exit sd_mod_exit(void)
{
        usb_deregister(&sd_driver);
}

module_init(sd_mod_init);
module_exit(sd_mod_exit);