path: root/drivers/media/usb/gspca/touptek.c

/*
 * 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.
 *
 * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */

#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", reply[0]);
		return -EIO;
	}
	return 0;
}

static void reg_w(struct gspca_dev *gspca_dev, u16 value, u16 index)
{
	char buff[1];
	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, 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;
	uint8_t buff[4];

	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);