/*
 * Copyright (c) 2001 Jean-Fredric Clere, Nikolas Zimmermann, Georg Acher
 *		      Mark Cave-Ayland, Carlo E Prelz, Dick Streefland
 * Copyright (c) 2002, 2003 Tuukka Toivonen
 * Copyright (c) 2008 Erik Andrén
 *
 * 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.
 *
 * P/N 861037:      Sensor HDCS1000        ASIC STV0600
 * P/N 861050-0010: Sensor HDCS1000        ASIC STV0600
 * P/N 861050-0020: Sensor Photobit PB100  ASIC STV0600-1 - QuickCam Express
 * P/N 861055:      Sensor ST VV6410       ASIC STV0610   - LEGO cam
 * P/N 861075-0040: Sensor HDCS1000        ASIC
 * P/N 961179-0700: Sensor ST VV6410       ASIC STV0602   - Dexxa WebCam USB
 * P/N 861040-0000: Sensor ST VV6410       ASIC STV0610   - QuickCam Web
 */

/*
 * The spec file for the PB-0100 suggests the following for best quality
 * images after the sensor has been reset :
 *
 * PB_ADCGAINL      = R60 = 0x03 (3 dec)      : sets low reference of ADC
						to produce good black level
 * PB_PREADCTRL     = R32 = 0x1400 (5120 dec) : Enables global gain changes
						through R53
 * PB_ADCMINGAIN    = R52 = 0x10 (16 dec)     : Sets the minimum gain for
						auto-exposure
 * PB_ADCGLOBALGAIN = R53 = 0x10 (16 dec)     : Sets the global gain
 * PB_EXPGAIN       = R14 = 0x11 (17 dec)     : Sets the auto-exposure value
 * PB_UPDATEINT     = R23 = 0x02 (2 dec)      : Sets the speed on
						auto-exposure routine
 * PB_CFILLIN       = R5  = 0x0E (14 dec)     : Sets the frame rate
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include "stv06xx_pb0100.h"

struct pb0100_ctrls {
	struct { /* one big happy control cluster... */
		struct v4l2_ctrl *autogain;
		struct v4l2_ctrl *gain;
		struct v4l2_ctrl *exposure;
		struct v4l2_ctrl *red;
		struct v4l2_ctrl *blue;
		struct v4l2_ctrl *natural;
	};
	struct v4l2_ctrl *target;
};

static struct v4l2_pix_format pb0100_mode[] = {
/* low res / subsample modes disabled as they are only half res horizontal,
   halving the vertical resolution does not seem to work */
	{
		320,
		240,
		V4L2_PIX_FMT_SGRBG8,
		V4L2_FIELD_NONE,
		.sizeimage = 320 * 240,
		.bytesperline = 320,
		.colorspace = V4L2_COLORSPACE_SRGB,
		.priv = PB0100_CROP_TO_VGA
	},
	{
		352,
		288,
		V4L2_PIX_FMT_SGRBG8,
		V4L2_FIELD_NONE,
		.sizeimage = 352 * 288,
		.bytesperline = 352,
		.colorspace = V4L2_COLORSPACE_SRGB,
		.priv = 0
	}
};

static int pb0100_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;
	struct pb0100_ctrls *ctrls = sd->sensor_priv;
	int err = -EINVAL;

	switch (ctrl->id) {
	case V4L2_CID_AUTOGAIN:
		err = pb0100_set_autogain(gspca_dev, ctrl->val);
		if (err)
			break;
		if (ctrl->val)
			break;
		err = pb0100_set_gain(gspca_dev, ctrls->gain->val);
		if (err)
			break;
		err = pb0100_set_exposure(gspca_dev, ctrls->exposure->val);
		break;
	case V4L2_CTRL_CLASS_USER + 0x1001:
		err = pb0100_set_autogain_target(gspca_dev, ctrl->val);
		break;
	}
	return err;
}

static const struct v4l2_ctrl_ops pb0100_ctrl_ops = {
	.s_ctrl = pb0100_s_ctrl,
};

static int pb0100_init_controls(struct sd *sd)
{
	struct v4l2_ctrl_handler *hdl = &sd->gspca_dev.ctrl_handler;
	struct pb0100_ctrls *ctrls;
	static const struct v4l2_ctrl_config autogain_target = {
		.ops = &pb0100_ctrl_ops,
		.id = V4L2_CTRL_CLASS_USER + 0x1000,
		.type = V4L2_CTRL_TYPE_INTEGER,
		.name = "Automatic Gain Target",
		.max = 255,
		.step = 1,
		.def = 128,
	};
	static const struct v4l2_ctrl_config natural_light = {
		.ops = &pb0100_ctrl_ops,
		.id = V4L2_CTRL_CLASS_USER + 0x1001,
		.type = V4L2_CTRL_TYPE_BOOLEAN,
		.name = "Natural Light Source",
		.max = 1,
		.step = 1,
		.def = 1,
	};

	ctrls = kzalloc(sizeof(*ctrls), GFP_KERNEL);
	if (!ctrls)
		return -ENOMEM;

	v4l2_ctrl_handler_init(hdl, 6);
	ctrls->autogain = v4l2_ctrl_new_std(hdl, &pb0100_ctrl_ops,
			V4L2_CID_AUTOGAIN, 0, 1, 1, 1);
	ctrls->exposure = v4l2_ctrl_new_std(hdl, &pb0100_ctrl_ops,
			V4L2_CID_EXPOSURE, 0, 511, 1, 12);
	ctrls->gain = v4l2_ctrl_new_std(hdl, &pb0100_ctrl_ops,
			V4L2_CID_GAIN, 0, 255, 1, 128);
	ctrls->red = v4l2_ctrl_new_std(hdl, &pb0100_ctrl_ops,
			V4L2_CID_RED_BALANCE, -255, 255, 1, 0);
	ctrls->blue = v4l2_ctrl_new_std(hdl, &pb0100_ctrl_ops,
			V4L2_CID_BLUE_BALANCE, -255, 255, 1, 0);
	ctrls->natural = v4l2_ctrl_new_custom(hdl, &natural_light, NULL);
	ctrls->target = v4l2_ctrl_new_custom(hdl, &autogain_target, NULL);
	if (hdl->error) {
		kfree(ctrls);
		return hdl->error;
	}
	sd->sensor_priv = ctrls;
	v4l2_ctrl_auto_cluster(5, &ctrls->autogain, 0, false);
	return 0;
}

static int pb0100_probe(struct sd *sd)
{
	u16 sensor;
	int err;

	err = stv06xx_read_sensor(sd, PB_IDENT, &sensor);

	if (err < 0)
		return -ENODEV;
	if ((sensor >> 8) != 0x64)
		return -ENODEV;

	pr_info("Photobit pb0100 sensor detected\n");

	sd->gspca_dev.cam.cam_mode = pb0100_mode;
	sd->gspca_dev.cam.nmodes = ARRAY_SIZE(pb0100_mode);

	return 0;
}

static int pb0100_start(struct sd *sd)
{
	int err, packet_size, max_packet_size;
	struct usb_host_interface *alt;
	struct usb_interface *intf;
	struct gspca_dev *gspca_dev = (struct gspca_dev *)sd;
	struct cam *cam = &sd->gspca_dev.cam;
	u32 mode = cam->cam_mode[sd->gspca_dev.curr_mode].priv;

	intf = usb_ifnum_to_if(sd->gspca_dev.dev, sd->gspca_dev.iface);
	alt = usb_altnum_to_altsetting(intf, sd->gspca_dev.alt);
	if (!alt)
		return -ENODEV;
	packet_size = le16_to_cpu(alt->endpoint[0].desc.wMaxPacketSize);

	/* If we don't have enough bandwidth use a lower framerate */
	max_packet_size = sd->sensor->max_packet_size[sd->gspca_dev.curr_mode];
	if (packet_size < max_packet_size)
		stv06xx_write_sensor(sd, PB_ROWSPEED, BIT(4)|BIT(3)|BIT(1));
	else
		stv06xx_write_sensor(sd, PB_ROWSPEED, BIT(5)|BIT(3)|BIT(1));

	/* Setup sensor window */
	if (mode & PB0100_CROP_TO_VGA) {
		stv06xx_write_sensor(sd, PB_RSTART, 30);
		stv06xx_write_sensor(sd, PB_CSTART, 20);
		stv06xx_write_sensor(sd, PB_RWSIZE, 240 - 1);
		stv06xx_write_sensor(sd, PB_CWSIZE, 320 - 1);
	} else {
		stv06xx_write_sensor(sd, PB_RSTART, 8);
		stv06xx_write_sensor(sd, PB_CSTART, 4);
		stv06xx_write_sensor(sd, PB_RWSIZE, 288 - 1);
		stv06xx_write_sensor(sd, PB_CWSIZE, 352 - 1);
	}

	if (mode & PB0100_SUBSAMPLE) {
		stv06xx_write_bridge(sd, STV_Y_CTRL, 0x02); /* Wrong, FIXME */
		stv06xx_write_bridge(sd, STV_X_CTRL, 0x06);

		stv06xx_write_bridge(sd, STV_SCAN_RATE, 0x10);
	} else {
		stv06xx_write_bridge(sd, STV_Y_CTRL, 0x01);
		stv06xx_write_bridge(sd, STV_X_CTRL, 0x0a);
		/* larger -> slower */
		stv06xx_write_bridge(sd, STV_SCAN_RATE, 0x20);
	}

	err = stv06xx_write_sensor(sd, PB_CONTROL, BIT(5)|BIT(3)|BIT(1));
	PDEBUG(D_STREAM, "Started stream, status: %d", err);

	return (err < 0) ? err : 0;
}

static int pb0100_stop(struct sd *sd)
{
	struct gspca_dev *gspca_dev = (struct gspca_dev *)sd;
	int err;

	err = stv06xx_write_sensor(sd, PB_ABORTFRAME, 1);

	if (err < 0)
		goto out;

	/* Set bit 1 to zero */
	err = stv06xx_write_sensor(sd, PB_CONTROL, BIT(5)|BIT(3));

	PDEBUG(D_STREAM, "Halting stream");
out:
	return (err < 0) ? err : 0;
}

/* FIXME: Sort the init commands out and put them into tables,
	  this is only for getting the camera to work */
/* FIXME: No error handling for now,
	  add this once the init has been converted to proper tables */
static int pb0100_init(struct sd *sd)
{
	stv06xx_write_bridge(sd, STV_REG00, 1);
	stv06xx_write_bridge(sd, STV_SCAN_RATE, 0);

	/* Reset sensor */
	stv06xx_write_sensor(sd, PB_RESET, 1);
	stv06xx_write_sensor(sd, PB_RESET, 0);

	/* Disable chip */
	stv06xx_write_sensor(sd, PB_CONTROL, BIT(5)|BIT(3));

	/* Gain stuff...*/
	stv06xx_write_sensor(sd, PB_PREADCTRL, BIT(12)|BIT(10)|BIT(6));
	stv06xx_write_sensor(sd, PB_ADCGLOBALGAIN, 12);

	/* Set up auto-exposure */
	/* ADC VREF_HI new setting for a transition
	  from the Expose1 to the Expose2 setting */
	stv06xx_write_sensor(sd, PB_R28, 12);
	/* gain max for autoexposure */
	stv06xx_write_sensor(sd, PB_ADCMAXGAIN, 180);
	/* gain min for autoexposure  */
	stv06xx_write_sensor(sd, PB_ADCMINGAIN, 12);
	/* Maximum frame integration time (programmed into R8)
	   allowed for auto-exposure routine */
	stv06xx_write_sensor(sd, PB_R54, 3);
	/* Minimum frame integration time (programmed into R8)
	   allowed for auto-exposure routine */
	stv06xx_write_sensor(sd, PB_R55, 0);
	stv06xx_write_sensor(sd, PB_UPDATEINT, 1);
	/* R15  Expose0 (maximum that auto-exposure may use) */
	stv06xx_write_sensor(sd, PB_R15, 800);
	/* R17  Expose2 (minimum that auto-exposure may use) */
	stv06xx_write_sensor(sd, PB_R17, 10);

	stv06xx_write_sensor(sd, PB_EXPGAIN, 0);

	/* 0x14 */
	stv06xx_write_sensor(sd, PB_VOFFSET, 0);
	/* 0x0D */
	stv06xx_write_sensor(sd, PB_ADCGAINH, 11);
	/* Set black level (important!) */
	stv06xx_write_sensor(sd, PB_ADCGAINL, 0);

	/* ??? */
	stv06xx_write_bridge(sd, STV_REG00, 0x11);
	stv06xx_write_bridge(sd, STV_REG03, 0x45);
	stv06xx_write_bridge(sd, STV_REG04, 0x07);

	/* Scan/timing for the sensor */
	stv06xx_write_sensor(sd, PB_ROWSPEED, BIT(4)|BIT(3)|BIT(1));
	stv06xx_write_sensor(sd, PB_CFILLIN, 14);
	stv06xx_write_sensor(sd, PB_VBL, 0);
	stv06xx_write_sensor(sd, PB_FINTTIME, 0);
	stv06xx_write_sensor(sd, PB_RINTTIME, 123);

	stv06xx_write_bridge(sd, STV_REG01, 0xc2);
	stv06xx_write_bridge(sd, STV_REG02, 0xb0);
	return 0;
}

static int pb0100_dump(struct sd *sd)
{
	return 0;
}

static int pb0100_set_gain(struct gspca_dev *gspca_dev, __s32 val)
{
	int err;
	struct sd *sd = (struct sd *) gspca_dev;
	struct pb0100_ctrls *ctrls = sd->sensor_priv;

	err = stv06xx_write_sensor(sd, PB_G1GAIN, val);
	if (!err)
		err = stv06xx_write_sensor(sd, PB_G2GAIN, val);
	PDEBUG(D_CONF, "Set green gain to %d, status: %d", val, err);

	if (!err)
		err = pb0100_set_red_balance(gspca_dev, ctrls->red->val);
	if (!err)
		err = pb0100_set_blue_balance(gspca_dev, ctrls->blue->val);

	return err;
}

static int pb0100_set_red_balance(struct gspca_dev *gspca_dev, __s32 val)
{
	int err;
	struct sd *sd = (struct sd *) gspca_dev;
	struct pb0100_ctrls *ctrls = sd->sensor_priv;

	val += ctrls->gain->val;
	if (val < 0)
		val = 0;
	else if (val > 255)
		val = 255;

	err = stv06xx_write_sensor(sd, PB_RGAIN, val);
	PDEBUG(D_CONF, "Set red gain to %d, status: %d", val, err);

	return err;
}

static int pb0100_set_blue_balance(struct gspca_dev *gspca_dev, __s32 val)
{
	int err;
	struct sd *sd = (struct sd *) gspca_dev;
	struct pb0100_ctrls *ctrls = sd->sensor_priv;

	val += ctrls->gain->val;
	if (val < 0)
		val = 0;
	else if (val > 255)
		val = 255;

	err = stv06xx_write_sensor(sd, PB_BGAIN, val);
	PDEBUG(D_CONF, "Set blue gain to %d, status: %d", val, err);

	return err;
}

static int pb0100_set_exposure(struct gspca_dev *gspca_dev, __s32 val)
{
	struct sd *sd = (struct sd *) gspca_dev;
	int err;

	err = stv06xx_write_sensor(sd, PB_RINTTIME, val);
	PDEBUG(D_CONF, "Set exposure to %d, status: %d", val, err);

	return err;
}

static int pb0100_set_autogain(struct gspca_dev *gspca_dev, __s32 val)
{
	int err;
	struct sd *sd = (struct sd *) gspca_dev;
	struct pb0100_ctrls *ctrls = sd->sensor_priv;

	if (val) {
		if (ctrls->natural->val)
			val = BIT(6)|BIT(4)|BIT(0);
		else
			val = BIT(4)|BIT(0);
	} else
		val = 0;

	err = stv06xx_write_sensor(sd, PB_EXPGAIN, val);
	PDEBUG(D_CONF, "Set autogain to %d (natural: %d), status: %d",
	       val, ctrls->natural->val, err);

	return err;
}

static int pb0100_set_autogain_target(struct gspca_dev *gspca_dev, __s32 val)
{
	int err, totalpixels, brightpixels, darkpixels;
	struct sd *sd = (struct sd *) gspca_dev;

	/* Number of pixels counted by the sensor when subsampling the pixels.
	 * Slightly larger than the real value to avoid oscillation */
	totalpixels = gspca_dev->pixfmt.width * gspca_dev->pixfmt.height;
	totalpixels = totalpixels/(8*8) + totalpixels/(64*64);

	brightpixels = (totalpixels * val) >> 8;
	darkpixels   = totalpixels - brightpixels;
	err = stv06xx_write_sensor(sd, PB_R21, brightpixels);
	if (!err)
		err = stv06xx_write_sensor(sd, PB_R22, darkpixels);

	PDEBUG(D_CONF, "Set autogain target to %d, status: %d", val, err);

	return err;
}