patch-2.4.5 linux/drivers/media/video/w9966.c

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diff -u --recursive --new-file v2.4.4/linux/drivers/media/video/w9966.c linux/drivers/media/video/w9966.c
@@ -0,0 +1,996 @@
+/*
+	Winbond w9966cf Webcam parport driver.
+
+	Version 0.32
+
+	Copyright (C) 2001 Jakob Kemi <jakob.kemi@post.utfors.se>
+
+	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., 675 Mass Ave, Cambridge, MA 02139, USA.
+*/
+/*
+	Supported devices:
+	*Lifeview FlyCam Supra (using the Philips saa7111a chip)
+
+	Does any other model using the w9966 interface chip exist ?
+
+	Todo:
+	
+	*Add a working EPP mode, since DMA ECP read isn't implemented
+	in the parport drivers. (That's why it's so sloow)
+
+	*Add support for other ccd-control chips than the saa7111
+	please send me feedback on what kind of chips you have.
+
+	*Add proper probing. I don't know what's wrong with the IEEE1284
+	parport drivers but (IEEE1284_MODE_NIBBLE|IEEE1284_DEVICE_ID)
+	and nibble read seems to be broken for some peripherals.
+
+	*Add probing for onboard SRAM, port directions etc. (if possible)
+
+	*Add support for the hardware compressed modes (maybe using v4l2)
+
+	*Fix better support for the capture window (no skewed images, v4l
+	interface to capt. window)
+
+	*Probably some bugs that I don't know of
+
+	Please support me by sending feedback!
+	
+	Changes:
+	
+	Alan Cox:	Removed RGB mode for kernel merge, added THIS_MODULE
+			and owner support for newer module locks
+*/
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/videodev.h>
+#include <linux/parport.h>
+
+//#define DEBUG				// Undef me for production
+
+#ifdef DEBUG
+#define DPRINTF(x, a...) printk(KERN_DEBUG "W9966: "__FUNCTION__ "(): "x, ##a)
+#else
+#define DPRINTF(x...)
+#endif
+
+/*
+ *	Defines, simple typedefs etc.
+ */
+
+#define W9966_DRIVERNAME	"W9966CF Webcam"
+#define W9966_MAXCAMS		4	// Maximum number of cameras
+#define W9966_RBUFFER		2048	// Read buffer (must be an even number)
+#define W9966_SRAMSIZE		131072	// 128kb
+#define W9966_SRAMID		0x02	// check w9966cf.pdf
+
+// Empirically determined window limits
+#define W9966_WND_MIN_X		16
+#define W9966_WND_MIN_Y		14
+#define W9966_WND_MAX_X		705
+#define W9966_WND_MAX_Y		253
+#define W9966_WND_MAX_W		(W9966_WND_MAX_X - W9966_WND_MIN_X)
+#define W9966_WND_MAX_H		(W9966_WND_MAX_Y - W9966_WND_MIN_Y)
+
+// Keep track of our current state
+#define W9966_STATE_PDEV	0x01
+#define W9966_STATE_CLAIMED	0x02
+#define W9966_STATE_VDEV	0x04
+
+#define W9966_I2C_W_ID		0x48
+#define W9966_I2C_R_ID		0x49
+#define W9966_I2C_R_DATA	0x08
+#define W9966_I2C_R_CLOCK	0x04
+#define W9966_I2C_W_DATA	0x02
+#define W9966_I2C_W_CLOCK	0x01
+
+struct w9966_dev {
+	unsigned char dev_state;
+	unsigned char i2c_state;
+	unsigned short ppmode;
+	struct parport* pport;
+	struct pardevice* pdev;
+	struct video_device vdev;
+	unsigned short width;
+	unsigned short height;
+	unsigned char brightness;
+	signed char contrast;
+	signed char color;
+	signed char hue;
+};
+
+/*
+ *	Module specific properties
+ */
+
+MODULE_AUTHOR("Jakob Kemi <jakob.kemi@post.utfors.se>");
+MODULE_DESCRIPTION("Winbond w9966cf WebCam driver (0.32)");
+
+#ifdef MODULE
+static const char* pardev[] = {[0 ... W9966_MAXCAMS] = ""};
+#else
+static const char* pardev[] = {[0 ... W9966_MAXCAMS] = "aggressive"};
+#endif
+MODULE_PARM(pardev, "1-" __MODULE_STRING(W9966_MAXCAMS) "s");
+MODULE_PARM_DESC(pardev, "pardev: where to search for\n\
+\teach camera. 'aggressive' means brute-force search.\n\
+\tEg: >pardev=parport3,aggressive,parport2,parport1< would assign
+\tcam 1 to parport3 and search every parport for cam 2 etc...");
+
+static int parmode = 0;
+MODULE_PARM(parmode, "i");
+MODULE_PARM_DESC(parmode, "parmode: transfer mode (0=auto, 1=ecp, 2=epp");
+
+static int video_nr = -1;
+MODULE_PARM(video_nr, "i");
+
+/*
+ *	Private data
+ */
+
+static struct w9966_dev w9966_cams[W9966_MAXCAMS];
+
+/*
+ *	Private function declares
+ */
+
+static inline void w9966_setState(struct w9966_dev* cam, int mask, int val);
+static inline int  w9966_getState(struct w9966_dev* cam, int mask, int val);
+static inline void w9966_pdev_claim(struct w9966_dev *vdev);
+static inline void w9966_pdev_release(struct w9966_dev *vdev);
+
+static int w9966_rReg(struct w9966_dev* cam, int reg);
+static int w9966_wReg(struct w9966_dev* cam, int reg, int data);
+static int w9966_rReg_i2c(struct w9966_dev* cam, int reg);
+static int w9966_wReg_i2c(struct w9966_dev* cam, int reg, int data);
+static int w9966_findlen(int near, int size, int maxlen);
+static int w9966_calcscale(int size, int min, int max, int* beg, int* end, unsigned char* factor);
+static int w9966_setup(struct w9966_dev* cam, int x1, int y1, int x2, int y2, int w, int h);
+
+static int  w9966_init(struct w9966_dev* cam, struct parport* port);
+static void w9966_term(struct w9966_dev* cam);
+
+static inline void w9966_i2c_setsda(struct w9966_dev* cam, int state);
+static inline int  w9966_i2c_setscl(struct w9966_dev* cam, int state);
+static inline int  w9966_i2c_getsda(struct w9966_dev* cam);
+static inline int  w9966_i2c_getscl(struct w9966_dev* cam);
+static int w9966_i2c_wbyte(struct w9966_dev* cam, int data);
+static int w9966_i2c_rbyte(struct w9966_dev* cam);
+
+static int  w9966_v4l_open(struct video_device *vdev, int mode);
+static void w9966_v4l_close(struct video_device *vdev);
+static int  w9966_v4l_ioctl(struct video_device *vdev, unsigned int cmd, void *arg);
+static long w9966_v4l_read(struct video_device *vdev, char *buf, unsigned long count, int noblock);
+
+/*
+ *	Private function defines
+ */
+
+
+// Set camera phase flags, so we know what to uninit when terminating 
+static inline void w9966_setState(struct w9966_dev* cam, int mask, int val)
+{
+	cam->dev_state = (cam->dev_state & ~mask) ^ val;
+}
+
+// Get camera phase flags
+static inline int w9966_getState(struct w9966_dev* cam, int mask, int val)
+{
+	return ((cam->dev_state & mask) == val);
+}
+
+// Claim parport for ourself
+static inline void w9966_pdev_claim(struct w9966_dev* cam)
+{
+	if (w9966_getState(cam, W9966_STATE_CLAIMED, W9966_STATE_CLAIMED))
+		return;
+	parport_claim_or_block(cam->pdev);
+	w9966_setState(cam, W9966_STATE_CLAIMED, W9966_STATE_CLAIMED);
+}
+
+// Release parport for others to use
+static inline void w9966_pdev_release(struct w9966_dev* cam)
+{
+	if (w9966_getState(cam, W9966_STATE_CLAIMED, 0))
+		return;
+	parport_release(cam->pdev);
+	w9966_setState(cam, W9966_STATE_CLAIMED, 0);
+}
+ 
+// Read register from W9966 interface-chip
+// Expects a claimed pdev
+// -1 on error, else register data (byte)
+static int w9966_rReg(struct w9966_dev* cam, int reg)
+{
+	// ECP, read, regtransfer, REG, REG, REG, REG, REG
+	const unsigned char addr = 0x80 | (reg & 0x1f);
+	unsigned char val;
+	
+	if (parport_negotiate(cam->pport, cam->ppmode | IEEE1284_ADDR) != 0)
+		return -1;
+	if (parport_write(cam->pport, &addr, 1) != 1)
+		return -1;
+	if (parport_negotiate(cam->pport, cam->ppmode | IEEE1284_DATA) != 0)
+		return -1;
+	if (parport_read(cam->pport, &val, 1) != 1)
+		return -1;
+
+	return val;
+}
+
+// Write register to W9966 interface-chip
+// Expects a claimed pdev
+// -1 on error
+static int w9966_wReg(struct w9966_dev* cam, int reg, int data)
+{
+	// ECP, write, regtransfer, REG, REG, REG, REG, REG
+	const unsigned char addr = 0xc0 | (reg & 0x1f);
+	const unsigned char val = data;
+	
+	if (parport_negotiate(cam->pport, cam->ppmode | IEEE1284_ADDR) != 0)
+		return -1;
+	if (parport_write(cam->pport, &addr, 1) != 1)
+		return -1;
+	if (parport_negotiate(cam->pport, cam->ppmode | IEEE1284_DATA) != 0)
+		return -1;
+	if (parport_write(cam->pport, &val, 1) != 1)
+		return -1;
+
+	return 0;
+}
+
+// Initialize camera device. Setup all internal flags, set a
+// default video mode, setup ccd-chip, register v4l device etc..
+// Also used for 'probing' of hardware.
+// -1 on error
+static int w9966_init(struct w9966_dev* cam, struct parport* port)
+{
+	if (cam->dev_state != 0)
+		return -1;
+	
+	cam->pport = port;
+	cam->brightness = 128;
+	cam->contrast = 64;
+	cam->color = 64;
+	cam->hue = 0;
+
+// Select requested transfer mode
+	switch(parmode)
+	{
+	default:	// Auto-detect (priority: hw-ecp, hw-epp, sw-ecp)
+	case 0:
+		if (port->modes & PARPORT_MODE_ECP)
+			cam->ppmode = IEEE1284_MODE_ECP;
+		else if (port->modes & PARPORT_MODE_EPP)
+			cam->ppmode = IEEE1284_MODE_EPP;
+		else
+			cam->ppmode = IEEE1284_MODE_ECP;
+		break;	
+	case 1:		// hw- or sw-ecp
+		cam->ppmode = IEEE1284_MODE_ECP;
+		break;
+	case 2:		// hw- or sw-epp
+		cam->ppmode = IEEE1284_MODE_EPP;
+	break;
+	}
+	
+// Tell the parport driver that we exists
+	cam->pdev = parport_register_device(port, "w9966", NULL, NULL, NULL, 0, NULL);
+	if (cam->pdev == NULL) {
+		DPRINTF("parport_register_device() failed\n");
+		return -1;
+	}
+	w9966_setState(cam, W9966_STATE_PDEV, W9966_STATE_PDEV);
+
+	w9966_pdev_claim(cam);
+	
+// Setup a default capture mode
+	if (w9966_setup(cam, 0, 0, 1023, 1023, 200, 160) != 0) {
+		DPRINTF("w9966_setup() failed.\n");
+		return -1;
+	}
+
+	w9966_pdev_release(cam);
+
+// Fill in the video_device struct and register us to v4l
+	memset(&cam->vdev, 0, sizeof(struct video_device));
+	strcpy(cam->vdev.name, W9966_DRIVERNAME);
+	cam->vdev.type = VID_TYPE_CAPTURE | VID_TYPE_SCALES;
+	cam->vdev.hardware = VID_HARDWARE_W9966;
+	cam->vdev.open = &w9966_v4l_open;
+	cam->vdev.close = &w9966_v4l_close;
+	cam->vdev.read = &w9966_v4l_read;
+	cam->vdev.ioctl = &w9966_v4l_ioctl;
+	cam->vdev.priv = (void*)cam;
+	cam->vdev.owner = THIS_MODULE;
+
+	if (video_register_device(&cam->vdev, VFL_TYPE_GRABBER, video_nr) == -1)		 
+		return -1;
+	
+	w9966_setState(cam, W9966_STATE_VDEV, W9966_STATE_VDEV);
+	
+	// All ok
+	printk(
+		"w9966cf: Found and initialized a webcam on %s.\n",
+		cam->pport->name
+	);
+	return 0;
+}
+
+
+// Terminate everything gracefully
+static void w9966_term(struct w9966_dev* cam)
+{
+// Unregister from v4l
+	if (w9966_getState(cam, W9966_STATE_VDEV, W9966_STATE_VDEV)) {
+		video_unregister_device(&cam->vdev);
+		w9966_setState(cam, W9966_STATE_VDEV, 0);
+	}
+
+// Terminate from IEEE1284 mode and release pdev block
+	if (w9966_getState(cam, W9966_STATE_PDEV, W9966_STATE_PDEV)) {
+		w9966_pdev_claim(cam);
+		parport_negotiate(cam->pport, IEEE1284_MODE_COMPAT);
+		w9966_pdev_release(cam);
+	}
+
+// Unregister from parport
+	if (w9966_getState(cam, W9966_STATE_PDEV, W9966_STATE_PDEV)) {
+		parport_unregister_device(cam->pdev);
+		w9966_setState(cam, W9966_STATE_PDEV, 0);
+	}
+}
+
+
+// Find a good length for capture window (used both for W and H)
+// A bit ugly but pretty functional. The capture length
+// have to match the downscale
+static int w9966_findlen(int near, int size, int maxlen)
+{
+	int bestlen = size;
+	int besterr = abs(near - bestlen);
+	int len;
+
+	for(len = size+1;len < maxlen;len++)
+	{
+		int err;
+		if ( ((64*size) %len) != 0)
+			continue;
+
+		err = abs(near - len);
+
+		// Only continue as long as we keep getting better values
+		if (err > besterr)
+			break;
+		
+		besterr = err;
+		bestlen = len;
+	}
+
+	return bestlen;
+}
+
+// Modify capture window (if necessary) 
+// and calculate downscaling
+// Return -1 on error
+static int w9966_calcscale(int size, int min, int max, int* beg, int* end, unsigned char* factor)
+{
+	int maxlen = max - min;
+	int len = *end - *beg + 1;
+	int newlen = w9966_findlen(len, size, maxlen);
+	int err = newlen - len; 
+
+	// Check for bad format
+	if (newlen > maxlen || newlen < size)
+		return -1;
+
+	// Set factor (6 bit fixed)
+	*factor = (64*size) / newlen;
+	if (*factor == 64)
+		*factor = 0x00;	// downscale is disabled
+	else
+		*factor |= 0x80; // set downscale-enable bit
+
+	// Modify old beginning and end
+	*beg -= err / 2;
+	*end += err - (err / 2);
+
+	// Move window if outside borders
+	if (*beg < min) {
+		*end += min - *beg;
+		*beg += min - *beg;
+	}
+	if (*end > max) {
+		*beg -= *end - max;
+		*end -= *end - max;
+	}
+
+	return 0;
+}
+
+// Setup the cameras capture window etc.
+// Expects a claimed pdev
+// return -1 on error
+static int w9966_setup(struct w9966_dev* cam, int x1, int y1, int x2, int y2, int w, int h)
+{
+	unsigned int i;
+	unsigned int enh_s, enh_e;
+	unsigned char scale_x, scale_y;
+	unsigned char regs[0x1c];
+	unsigned char saa7111_regs[] = {
+		0x21, 0x00, 0xd8, 0x23, 0x00, 0x80, 0x80, 0x00,
+		0x88, 0x10, 0x80, 0x40, 0x40, 0x00, 0x01, 0x00,
+		0x48, 0x0c, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x71, 0xe7, 0x00, 0x00, 0xc0
+	};
+	
+	
+	if (w*h*2 > W9966_SRAMSIZE)
+	{
+		DPRINTF("capture window exceeds SRAM size!.\n");
+		w = 200; h = 160;	// Pick default values
+	}
+
+	w &= ~0x1;
+	if (w < 2) w = 2;
+	if (h < 1) h = 1;
+	if (w > W9966_WND_MAX_W) w = W9966_WND_MAX_W;
+	if (h > W9966_WND_MAX_H) h = W9966_WND_MAX_H;
+
+	cam->width = w;
+	cam->height = h;
+
+	enh_s = 0;	
+	enh_e = w*h*2;
+	
+// Modify capture window if necessary and calculate downscaling
+	if (
+		w9966_calcscale(w, W9966_WND_MIN_X, W9966_WND_MAX_X, &x1, &x2, &scale_x) != 0 ||
+		w9966_calcscale(h, W9966_WND_MIN_Y, W9966_WND_MAX_Y, &y1, &y2, &scale_y) != 0
+	) return -1;
+
+	DPRINTF(
+		"%dx%d, x: %d<->%d, y: %d<->%d, sx: %d/64, sy: %d/64.\n",
+		w, h, x1, x2, y1, y2, scale_x&~0x80, scale_y&~0x80
+	);
+	
+// Setup registers
+	regs[0x00] = 0x00;			// Set normal operation
+	regs[0x01] = 0x18;			// Capture mode
+	regs[0x02] = scale_y;			// V-scaling
+	regs[0x03] = scale_x;			// H-scaling
+	
+	// Capture window	
+	regs[0x04] = (x1 & 0x0ff);		// X-start (8 low bits)
+	regs[0x05] = (x1 & 0x300)>>8;		// X-start (2 high bits)
+	regs[0x06] = (y1 & 0x0ff);		// Y-start (8 low bits)
+	regs[0x07] = (y1 & 0x300)>>8;		// Y-start (2 high bits)
+	regs[0x08] = (x2 & 0x0ff);		// X-end (8 low bits)
+	regs[0x09] = (x2 & 0x300)>>8;		// X-end (2 high bits)
+	regs[0x0a] = (y2 & 0x0ff);		// Y-end (8 low bits)
+
+	regs[0x0c] = W9966_SRAMID;		// SRAM-banks (1x 128kb)
+	
+	// Enhancement layer
+	regs[0x0d] = (enh_s& 0x000ff);		// Enh. start (0-7)
+	regs[0x0e] = (enh_s& 0x0ff00)>>8;	// Enh. start (8-15)
+	regs[0x0f] = (enh_s& 0x70000)>>16;	// Enh. start (16-17/18??)
+	regs[0x10] = (enh_e& 0x000ff);		// Enh. end (0-7)
+	regs[0x11] = (enh_e& 0x0ff00)>>8;	// Enh. end (8-15)
+	regs[0x12] = (enh_e& 0x70000)>>16;	// Enh. end (16-17/18??)
+
+	// Misc
+	regs[0x13] = 0x40;			// VEE control (raw 4:2:2)
+	regs[0x17] = 0x00;			// ???
+	regs[0x18] = cam->i2c_state = 0x00;	// Serial bus
+	regs[0x19] = 0xff;			// I/O port direction control
+	regs[0x1a] = 0xff;			// I/O port data register
+	regs[0x1b] = 0x10;			// ???
+	
+	// SAA7111 chip settings
+	saa7111_regs[0x0a] = cam->brightness;
+	saa7111_regs[0x0b] = cam->contrast;
+	saa7111_regs[0x0c] = cam->color;
+	saa7111_regs[0x0d] = cam->hue;
+
+// Reset (ECP-fifo & serial-bus)
+	if (w9966_wReg(cam, 0x00, 0x03) == -1)
+		return -1;
+
+// Write regs to w9966cf chip
+	for (i = 0; i < 0x1c; i++)
+		if (w9966_wReg(cam, i, regs[i]) == -1)
+			return -1;
+
+// Write regs to saa7111 chip
+	for (i = 0; i < 0x20; i++)
+		if (w9966_wReg_i2c(cam, i, saa7111_regs[i]) == -1)
+			return -1;
+
+	return 0;
+}
+
+/*
+ *	Ugly and primitive i2c protocol functions
+ */
+
+// Sets the data line on the i2c bus.
+// Expects a claimed pdev.
+static inline void w9966_i2c_setsda(struct w9966_dev* cam, int state)
+{
+	if (state)
+		cam->i2c_state |= W9966_I2C_W_DATA;
+	else
+		cam->i2c_state &= ~W9966_I2C_W_DATA;
+	
+	w9966_wReg(cam, 0x18, cam->i2c_state);
+	udelay(5);
+}
+
+// Sets the clock line on the i2c bus.
+// Expects a claimed pdev. -1 on error
+static inline int w9966_i2c_setscl(struct w9966_dev* cam, int state)
+{
+	int timeout;
+	if (state)
+		cam->i2c_state |= W9966_I2C_W_CLOCK;
+	else
+		cam->i2c_state &= ~W9966_I2C_W_CLOCK;
+
+	w9966_wReg(cam, 0x18, cam->i2c_state);
+	udelay(5);
+	
+	// we go to high, we also expect the peripheral to ack.
+	if (state) {
+		timeout = jiffies + 100;
+		while (!w9966_i2c_getscl(cam)) {
+			if (jiffies > timeout)
+				return -1;
+		}
+	}
+	return 0;
+}
+
+// Get peripheral data line
+// Expects a claimed pdev.
+static inline int w9966_i2c_getsda(struct w9966_dev* cam)
+{
+	const unsigned char state = w9966_rReg(cam, 0x18);
+	return ((state & W9966_I2C_R_DATA) > 0);
+}
+
+// Get peripheral clock line
+// Expects a claimed pdev.
+static inline int w9966_i2c_getscl(struct w9966_dev* cam)
+{
+	const unsigned char state = w9966_rReg(cam, 0x18);
+	return ((state & W9966_I2C_R_CLOCK) > 0);
+}
+
+// Write a byte with ack to the i2c bus.
+// Expects a claimed pdev. -1 on error
+static int w9966_i2c_wbyte(struct w9966_dev* cam, int data)
+{
+	int i;
+	for (i = 7; i >= 0; i--)
+	{
+		w9966_i2c_setsda(cam, (data >> i) & 0x01);
+
+		if (w9966_i2c_setscl(cam, 1) == -1)
+			return -1;			
+		w9966_i2c_setscl(cam, 0);
+	}
+
+	w9966_i2c_setsda(cam, 1);
+	
+	if (w9966_i2c_setscl(cam, 1) == -1)
+		return -1;
+	w9966_i2c_setscl(cam, 0);
+	
+	return 0;
+}
+
+// Read a data byte with ack from the i2c-bus
+// Expects a claimed pdev. -1 on error
+static int w9966_i2c_rbyte(struct w9966_dev* cam)
+{
+	unsigned char data = 0x00;
+	int i;	
+	
+	w9966_i2c_setsda(cam, 1);
+
+	for (i = 0; i < 8; i++)
+	{
+		if (w9966_i2c_setscl(cam, 1) == -1)
+			return -1;
+		data = data << 1;
+		if (w9966_i2c_getsda(cam))
+			data |= 0x01;
+		
+		w9966_i2c_setscl(cam, 0);
+	}
+	return data;
+}
+
+// Read a register from the i2c device.
+// Expects claimed pdev. -1 on error
+static int w9966_rReg_i2c(struct w9966_dev* cam, int reg)
+{
+	int data;
+
+	w9966_i2c_setsda(cam, 0);
+	w9966_i2c_setscl(cam, 0);
+
+	if (
+		w9966_i2c_wbyte(cam, W9966_I2C_W_ID) == -1 ||
+		w9966_i2c_wbyte(cam, reg) == -1
+	)
+		return -1;
+
+	w9966_i2c_setsda(cam, 1);
+	if (w9966_i2c_setscl(cam, 1) == -1)
+		return -1;
+	w9966_i2c_setsda(cam, 0);
+	w9966_i2c_setscl(cam, 0);
+
+	if (
+		w9966_i2c_wbyte(cam, W9966_I2C_R_ID) == -1 ||
+		(data = w9966_i2c_rbyte(cam)) == -1
+	)
+		return -1;
+
+	w9966_i2c_setsda(cam, 0);
+	
+	if (w9966_i2c_setscl(cam, 1) == -1)
+		return -1;
+	w9966_i2c_setsda(cam, 1);
+	
+	return data;
+}
+
+// Write a register to the i2c device.
+// Expects claimed pdev. -1 on error
+static int w9966_wReg_i2c(struct w9966_dev* cam, int reg, int data)
+{
+	w9966_i2c_setsda(cam, 0);
+	w9966_i2c_setscl(cam, 0);
+
+	if (
+		w9966_i2c_wbyte(cam, W9966_I2C_W_ID) == -1 ||
+		w9966_i2c_wbyte(cam, reg) == -1 ||
+		w9966_i2c_wbyte(cam, data) == -1
+	)
+		return -1;
+
+	w9966_i2c_setsda(cam, 0);
+	if (w9966_i2c_setscl(cam, 1) == -1)
+		return -1;
+		
+	w9966_i2c_setsda(cam, 1);
+
+	return 0;
+}
+
+/*
+ *	Video4linux interfacing
+ */
+
+static int w9966_v4l_open(struct video_device *vdev, int flags)
+{
+	return 0;
+}
+
+static void w9966_v4l_close(struct video_device *vdev)
+{
+}
+
+static int w9966_v4l_ioctl(struct video_device *vdev, unsigned int cmd, void *arg)
+{
+	struct w9966_dev *cam = (struct w9966_dev*)vdev->priv;
+	
+	switch(cmd)
+	{
+	case VIDIOCGCAP:
+	{
+		struct video_capability vcap = {
+			W9966_DRIVERNAME,	// name
+			VID_TYPE_CAPTURE | VID_TYPE_SCALES,	// type
+			1, 0,			// vid, aud channels
+			W9966_WND_MAX_W,	// max w
+			W9966_WND_MAX_H,	// max h
+			2, 1			// min w, min h
+		};
+
+		if(copy_to_user(arg, &vcap, sizeof(vcap)) != 0)
+			return -EFAULT;
+
+		return 0;
+	}
+	case VIDIOCGCHAN:
+	{
+		struct video_channel vch;
+		if(copy_from_user(&vch, arg, sizeof(vch)) != 0)
+			return -EFAULT;
+
+		if(vch.channel != 0)	// We only support one channel (#0)
+			return -EINVAL;
+
+		strcpy(vch.name, "CCD-input");
+		vch.flags = 0;		// We have no tuner or audio
+		vch.tuners = 0;
+		vch.type = VIDEO_TYPE_CAMERA;
+		vch.norm = 0;		// ???
+		
+		if(copy_to_user(arg, &vch, sizeof(vch)) != 0)
+			return -EFAULT;
+		
+		return 0;
+	}
+	case VIDIOCSCHAN:
+	{
+		struct video_channel vch;
+		if(copy_from_user(&vch, arg, sizeof(vch) ) != 0)
+			return -EFAULT;
+		
+		if(vch.channel != 0)
+			return -EINVAL;
+		
+		return 0;
+	}
+	case VIDIOCGTUNER:
+	{
+		struct video_tuner vtune;
+		if(copy_from_user(&vtune, arg, sizeof(vtune)) != 0)
+			return -EFAULT;
+		
+		if(vtune.tuner != 0);
+			return -EINVAL;
+		
+		strcpy(vtune.name, "no tuner");
+		vtune.rangelow = 0;
+		vtune.rangehigh = 0;
+		vtune.flags = VIDEO_TUNER_NORM;
+		vtune.mode = VIDEO_MODE_AUTO;
+		vtune.signal = 0xffff;
+		
+		if(copy_to_user(arg, &vtune, sizeof(vtune)) != 0)
+			return -EFAULT;
+		
+		return 0;
+	}
+	case VIDIOCSTUNER:
+	{
+		struct video_tuner vtune;
+		if (copy_from_user(&vtune, arg, sizeof(vtune)) != 0)
+			return -EFAULT;
+		
+		if (vtune.tuner != 0)
+			return -EINVAL;
+		
+		if (vtune.mode != VIDEO_MODE_AUTO)
+			return -EINVAL;
+		
+		return 0;
+	}
+	case VIDIOCGPICT:
+	{
+		struct video_picture vpic = {
+			cam->brightness << 8,	// brightness
+			(cam->hue + 128) << 8,	// hue
+			cam->color << 9,	// color
+			cam->contrast << 9,	// contrast
+			0x8000,			// whiteness
+			16, VIDEO_PALETTE_YUV422// bpp, palette format
+		};
+
+		if(copy_to_user(arg, &vpic, sizeof(vpic)) != 0)
+			return -EFAULT;
+
+		return 0;
+	}
+	case VIDIOCSPICT:
+	{
+		struct video_picture vpic;
+		if(copy_from_user(&vpic, arg, sizeof(vpic)) != 0)
+			return -EFAULT;
+		
+		if (vpic.depth != 16 || vpic.palette != VIDEO_PALETTE_YUV422)
+			return -EINVAL;
+			
+		cam->brightness = vpic.brightness >> 8;
+		cam->hue = (vpic.hue >> 8) - 128;
+		cam->color = vpic.colour >> 9;
+		cam->contrast = vpic.contrast >> 9;
+
+		w9966_pdev_claim(cam);
+		
+		if (
+			w9966_wReg_i2c(cam, 0x0a, cam->brightness) == -1 ||
+			w9966_wReg_i2c(cam, 0x0b, cam->contrast) == -1 ||
+			w9966_wReg_i2c(cam, 0x0c, cam->color) == -1 ||
+			w9966_wReg_i2c(cam, 0x0d, cam->hue) == -1
+		) {
+			w9966_pdev_release(cam);
+			return -EFAULT;
+		}
+		
+		w9966_pdev_release(cam);
+		return 0;
+	}
+	case VIDIOCSWIN:
+	{
+		int ret;
+		struct video_window vwin;
+		
+		if (copy_from_user(&vwin, arg, sizeof(vwin)) != 0)
+			return -EFAULT;		
+		if (vwin.flags != 0)
+			return -EINVAL;
+		if (vwin.clipcount != 0)
+			return -EINVAL;
+		if (vwin.width < 2 || vwin.width > W9966_WND_MAX_W)
+			return -EINVAL;		
+		if (vwin.height < 1 || vwin.height > W9966_WND_MAX_H)
+			return -EINVAL;
+
+		// Update camera regs
+		w9966_pdev_claim(cam);
+		ret = w9966_setup(cam, 0, 0, 1023, 1023, vwin.width, vwin.height);
+		w9966_pdev_release(cam);
+		
+		if (ret != 0) {
+			DPRINTF("VIDIOCSWIN: w9966_setup() failed.\n");
+			return -EFAULT;
+		}
+		
+		return 0;
+	}
+	case VIDIOCGWIN:
+	{
+		struct video_window vwin;
+		memset(&vwin, 0, sizeof(vwin));
+		
+		vwin.width = cam->width;
+		vwin.height = cam->height;
+		
+		if(copy_to_user(arg, &vwin, sizeof(vwin)) != 0)
+			return -EFAULT;
+		
+		return 0;
+	}
+	// Unimplemented
+	case VIDIOCCAPTURE:	
+	case VIDIOCGFBUF:
+	case VIDIOCSFBUF:
+	case VIDIOCKEY:
+	case VIDIOCGFREQ:
+	case VIDIOCSFREQ:
+	case VIDIOCGAUDIO:
+	case VIDIOCSAUDIO:
+		return -EINVAL;
+	default:
+		return -ENOIOCTLCMD;
+	}
+	return 0;
+}
+
+// Capture data
+static long w9966_v4l_read(struct video_device *vdev, char *buf, unsigned long count,  int noblock)
+{
+	struct w9966_dev *cam = (struct w9966_dev *)vdev->priv;
+	unsigned char addr = 0xa0;	// ECP, read, CCD-transfer, 00000
+	unsigned char* dest = (unsigned char*)buf;
+	unsigned long dleft = count;
+	
+	// Why would anyone want more than this??
+	if (count > cam->width * cam->height * 2)
+		return -EINVAL;
+	
+	w9966_pdev_claim(cam);
+	w9966_wReg(cam, 0x00, 0x02);	// Reset ECP-FIFO buffer
+	w9966_wReg(cam, 0x00, 0x00);	// Return to normal operation
+	w9966_wReg(cam, 0x01, 0x98);	// Enable capture
+
+	// write special capture-addr and negotiate into data transfer	
+	if (
+		(parport_negotiate(cam->pport, cam->ppmode|IEEE1284_ADDR) != 0	)||
+		(parport_write(cam->pport, &addr, 1) != 1						)||
+		(parport_negotiate(cam->pport, cam->ppmode|IEEE1284_DATA) != 0	)
+	) {
+		w9966_pdev_release(cam);
+		return -EFAULT;
+	}
+	
+	while(dleft > 0)
+	{
+		unsigned long tsize = (dleft > W9966_RBUFFER) ? W9966_RBUFFER : dleft;
+		unsigned char tbuf[W9966_RBUFFER];
+	
+		if (parport_read(cam->pport, tbuf, tsize) < tsize) {
+			w9966_pdev_release(cam);
+			return -EFAULT;
+		}
+		if (copy_to_user(dest, tbuf, tsize) != 0) {
+			w9966_pdev_release(cam);
+			return -EFAULT;
+		}
+		dest += tsize;
+		dleft -= tsize;
+	}
+	
+	w9966_wReg(cam, 0x01, 0x18);	// Disable capture
+	w9966_pdev_release(cam);
+
+	return count;
+}
+
+
+// Called once for every parport on init
+static void w9966_attach(struct parport *port)
+{
+	int i;
+	
+	for (i = 0; i < W9966_MAXCAMS; i++)
+	{
+		if (w9966_cams[i].dev_state != 0)	// Cam is already assigned
+			continue;
+		if (
+			strcmp(pardev[i], "aggressive") == 0 ||
+			strcmp(pardev[i], port->name) == 0
+		) {
+			if (w9966_init(&w9966_cams[i], port) != 0)
+			w9966_term(&w9966_cams[i]);
+			break;	// return
+		}
+	}
+}
+
+// Called once for every parport on termination
+static void w9966_detach(struct parport *port)
+{
+	int i;
+	for (i = 0; i < W9966_MAXCAMS; i++)
+	if (w9966_cams[i].dev_state != 0 && w9966_cams[i].pport == port)
+		w9966_term(&w9966_cams[i]);
+}
+
+
+static struct parport_driver w9966_ppd = {
+	W9966_DRIVERNAME,
+	w9966_attach,
+	w9966_detach,
+	NULL
+};
+
+// Module entry point
+static int __init w9966_mod_init(void)
+{
+	int i;
+	for (i = 0; i < W9966_MAXCAMS; i++)
+		w9966_cams[i].dev_state = 0;
+
+	return parport_register_driver(&w9966_ppd);
+}
+
+// Module cleanup
+static void __exit w9966_mod_term(void)
+{
+	parport_unregister_driver(&w9966_ppd);
+}
+
+module_init(w9966_mod_init);
+module_exit(w9966_mod_term);

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TCL-scripts by Sam Shen (who was at: slshen@lbl.gov)