bw-qcam.c

h内核

			lo = (qc_waithand2(q, 1) >> 1);
			hi = (read_lpstatus(q) >> 3) & 0x1f;
			write_lpcontrol(q, 0x2e);
			lo2 = (qc_waithand2(q, 0) >> 1);
			hi2 = (read_lpstatus(q) >> 3) & 0x1f;
			switch (q->bpp) 
			{
				case 4:
					buffer[0] = lo & 0xf;
					buffer[1] = ((lo & 0x70) >> 4) | ((hi & 1) << 3);
					buffer[2] = (hi & 0x1e) >> 1;
					buffer[3] = lo2 & 0xf;
					buffer[4] = ((lo2 & 0x70) >> 4) | ((hi2 & 1) << 3);
					buffer[5] = (hi2 & 0x1e) >> 1;
					ret = 6;
					break;
				case 6:
					buffer[0] = lo & 0x3f;
					buffer[1] = ((lo & 0x40) >> 6) | (hi << 1);
					buffer[2] = lo2 & 0x3f;
					buffer[3] = ((lo2 & 0x40) >> 6) | (hi2 << 1);
					ret = 4;
					break;
			}
			break;

		case QC_UNIDIR:	/* Unidirectional Port */
			write_lpcontrol(q, 6);
			lo = (qc_waithand(q, 1) & 0xf0) >> 4;
			write_lpcontrol(q, 0xe);
			hi = (qc_waithand(q, 0) & 0xf0) >> 4;

			switch (q->bpp) 
			{
				case 4:
					buffer[0] = lo;
					buffer[1] = hi;
					ret = 2;
					break;
				case 6:
					switch (state) 
					{
						case 0:
							buffer[0] = (lo << 2) | ((hi & 0xc) >> 2);
							q->saved_bits = (hi & 3) << 4;
							state = 1;
							ret = 1;
							break;
						case 1:
							buffer[0] = lo | q->saved_bits;
							q->saved_bits = hi << 2;
							state = 2;
							ret = 1;
							break;
						case 2:
							buffer[0] = ((lo & 0xc) >> 2) | q->saved_bits;
							buffer[1] = ((lo & 3) << 4) | hi;
							state = 0;
							ret = 2;
							break;
					}
					break;
			}
			break;
	}
	return ret;
}

/* requests a scan from the camera.  It sends the correct instructions
 * to the camera and then reads back the correct number of bytes.  In
 * previous versions of this routine the return structure contained
 * the raw output from the camera, and there was a 'qc_convertscan'
 * function that converted that to a useful format.  In version 0.3 I
 * rolled qc_convertscan into qc_scan and now I only return the
 * converted scan.  The format is just an one-dimensional array of
 * characters, one for each pixel, with 0=black up to n=white, where
 * n=2^(bit depth)-1.  Ask me for more details if you don't understand
 * this. */

static long qc_capture(struct qcam_device * q, char __user *buf, unsigned long len)
{
	int i, j, k, yield;
	int bytes;
	int linestotrans, transperline;
	int divisor;
	int pixels_per_line;
	int pixels_read = 0;
	int got=0;
	char buffer[6];
	int  shift=8-q->bpp;
	char invert;

	if (q->mode == -1) 
		return -ENXIO;

	qc_command(q, 0x7);
	qc_command(q, q->mode);

	if ((q->port_mode & QC_MODE_MASK) == QC_BIDIR) 
	{
		write_lpcontrol(q, 0x2e);	/* turn port around */
		write_lpcontrol(q, 0x26);
		(void) qc_waithand(q, 1);
		write_lpcontrol(q, 0x2e);
		(void) qc_waithand(q, 0);
	}
	
	/* strange -- should be 15:63 below, but 4bpp is odd */
	invert = (q->bpp == 4) ? 16 : 63;

	linestotrans = q->height / q->transfer_scale;
	pixels_per_line = q->width / q->transfer_scale;
	transperline = q->width * q->bpp;
	divisor = (((q->port_mode & QC_MODE_MASK) == QC_BIDIR) ? 24 : 8) *
	    q->transfer_scale;
	transperline = (transperline + divisor - 1) / divisor;

	for (i = 0, yield = yieldlines; i < linestotrans; i++) 
	{
		for (pixels_read = j = 0; j < transperline; j++) 
		{
			bytes = qc_readbytes(q, buffer);
			for (k = 0; k < bytes && (pixels_read + k) < pixels_per_line; k++) 
			{
				int o;
				if (buffer[k] == 0 && invert == 16) 
				{
					/* 4bpp is odd (again) -- inverter is 16, not 15, but output
					   must be 0-15 -- bls */
					buffer[k] = 16;
				}
				o=i*pixels_per_line + pixels_read + k;
				if(o<len)
				{
					got++;
					put_user((invert - buffer[k])<<shift, buf+o);
				}
			}
			pixels_read += bytes;
		}
		(void) qc_readbytes(q, NULL);	/* reset state machine */
		
		/* Grabbing an entire frame from the quickcam is a lengthy
		   process. We don't (usually) want to busy-block the
		   processor for the entire frame. yieldlines is a module
		   parameter. If we yield every line, the minimum frame
		   time will be 240 / 200 = 1.2 seconds. The compile-time
		   default is to yield every 4 lines. */
		if (i >= yield) {
			msleep_interruptible(5);
			yield = i + yieldlines;
		}
	}

	if ((q->port_mode & QC_MODE_MASK) == QC_BIDIR) 
	{
		write_lpcontrol(q, 2);
		write_lpcontrol(q, 6);
		udelay(3);
		write_lpcontrol(q, 0xe);
	}
	if(got<len)
		return got;
	return len;
}

/*
 *	Video4linux interfacing
 */

static int qcam_do_ioctl(struct inode *inode, struct file *file,
			 unsigned int cmd, void *arg)
{
	struct video_device *dev = video_devdata(file);
	struct qcam_device *qcam=(struct qcam_device *)dev;
	
	switch(cmd)
	{
		case VIDIOCGCAP:
		{
			struct video_capability *b = arg;
			strcpy(b->name, "Quickcam");
			b->type = VID_TYPE_CAPTURE|VID_TYPE_SCALES|VID_TYPE_MONOCHROME;
			b->channels = 1;
			b->audios = 0;
			b->maxwidth = 320;
			b->maxheight = 240;
			b->minwidth = 80;
			b->minheight = 60;
			return 0;
		}
		case VIDIOCGCHAN:
		{
			struct video_channel *v = arg;
			if(v->channel!=0)
				return -EINVAL;
			v->flags=0;
			v->tuners=0;
			/* Good question.. its composite or SVHS so.. */
			v->type = VIDEO_TYPE_CAMERA;
			strcpy(v->name, "Camera");
			return 0;
		}
		case VIDIOCSCHAN:
		{
			struct video_channel *v = arg;
			if(v->channel!=0)
				return -EINVAL;
			return 0;
		}
		case VIDIOCGTUNER:
		{
			struct video_tuner *v = arg;
			if(v->tuner)
				return -EINVAL;
			strcpy(v->name, "Format");
			v->rangelow=0;
			v->rangehigh=0;
			v->flags= 0;
			v->mode = VIDEO_MODE_AUTO;
			return 0;
		}
		case VIDIOCSTUNER:
		{
			struct video_tuner *v = arg;
			if(v->tuner)
				return -EINVAL;
			if(v->mode!=VIDEO_MODE_AUTO)
				return -EINVAL;
			return 0;
		}
		case VIDIOCGPICT:
		{
			struct video_picture *p = arg;
			p->colour=0x8000;
			p->hue=0x8000;
			p->brightness=qcam->brightness<<8;
			p->contrast=qcam->contrast<<8;
			p->whiteness=qcam->whitebal<<8;
			p->depth=qcam->bpp;
			p->palette=VIDEO_PALETTE_GREY;
			return 0;
		}
		case VIDIOCSPICT:
		{
			struct video_picture *p = arg;
			if(p->palette!=VIDEO_PALETTE_GREY)
			    	return -EINVAL;
			if(p->depth!=4 && p->depth!=6)
				return -EINVAL;
			
			/*
			 *	Now load the camera.
			 */

			qcam->brightness = p->brightness>>8;
			qcam->contrast = p->contrast>>8;
			qcam->whitebal = p->whiteness>>8;
			qcam->bpp = p->depth;

			down(&qcam->lock);			
			qc_setscanmode(qcam);
			up(&qcam->lock);
			qcam->status |= QC_PARAM_CHANGE;

			return 0;
		}
		case VIDIOCSWIN:
		{
			struct video_window *vw = arg;
			if(vw->flags)
				return -EINVAL;
			if(vw->clipcount)
				return -EINVAL;
			if(vw->height<60||vw->height>240)
				return -EINVAL;
			if(vw->width<80||vw->width>320)
				return -EINVAL;
				
			qcam->width = 320;
			qcam->height = 240;
			qcam->transfer_scale = 4;
			
			if(vw->width>=160 && vw->height>=120)
			{
				qcam->transfer_scale = 2;
			}
			if(vw->width>=320 && vw->height>=240)
			{
				qcam->width = 320;
				qcam->height = 240;
				qcam->transfer_scale = 1;
			}
			down(&qcam->lock);
			qc_setscanmode(qcam);
			up(&qcam->lock);
			
			/* We must update the camera before we grab. We could
			   just have changed the grab size */
			qcam->status |= QC_PARAM_CHANGE;
			
			/* Ok we figured out what to use from our wide choice */
			return 0;
		}
		case VIDIOCGWIN:
		{
			struct video_window *vw = arg;
			memset(vw, 0, sizeof(*vw));
			vw->width=qcam->width/qcam->transfer_scale;
			vw->height=qcam->height/qcam->transfer_scale;
			return 0;
		}
		case VIDIOCKEY:
			return 0;
		case VIDIOCCAPTURE:
		case VIDIOCGFBUF:
		case VIDIOCSFBUF:
		case VIDIOCGFREQ:
		case VIDIOCSFREQ:
		case VIDIOCGAUDIO:
		case VIDIOCSAUDIO:
			return -EINVAL;
		default:
			return -ENOIOCTLCMD;
	}
	return 0;
}

static int qcam_ioctl(struct inode *inode, struct file *file,
		     unsigned int cmd, unsigned long arg)
{
	return video_usercopy(inode, file, cmd, arg, qcam_do_ioctl);
}

static ssize_t qcam_read(struct file *file, char __user *buf,
			 size_t count, loff_t *ppos)
{
	struct video_device *v = video_devdata(file);
	struct qcam_device *qcam=(struct qcam_device *)v;
	int len;
	parport_claim_or_block(qcam->pdev);
	
	down(&qcam->lock);
	
	qc_reset(qcam);

	/* Update the camera parameters if we need to */
	if (qcam->status & QC_PARAM_CHANGE)
		qc_set(qcam);

	len=qc_capture(qcam, buf,count);
	
	up(&qcam->lock);
	
	parport_release(qcam->pdev);
	return len;
}
 
static struct file_operations qcam_fops = {
	.owner		= THIS_MODULE,
	.open           = video_exclusive_open,
	.release        = video_exclusive_release,
	.ioctl          = qcam_ioctl,
	.read		= qcam_read,
	.llseek         = no_llseek,
};
static struct video_device qcam_template=
{
	.owner		= THIS_MODULE,
	.name		= "Connectix Quickcam",
	.type		= VID_TYPE_CAPTURE,
	.hardware	= VID_HARDWARE_QCAM_BW,
	.fops           = &qcam_fops,
};

#define MAX_CAMS 4
static struct qcam_device *qcams[MAX_CAMS];
static unsigned int num_cams = 0;

static int init_bwqcam(struct parport *port)
{
	struct qcam_device *qcam;

	if (num_cams == MAX_CAMS)
	{
		printk(KERN_ERR "Too many Quickcams (max %d)\n", MAX_CAMS);
		return -ENOSPC;
	}

	qcam=qcam_init(port);
	if(qcam==NULL)
		return -ENODEV;
		
	parport_claim_or_block(qcam->pdev);

	qc_reset(qcam);
	
	if(qc_detect(qcam)==0)
	{
		parport_release(qcam->pdev);
		parport_unregister_device(qcam->pdev);
		kfree(qcam);
		return -ENODEV;
	}
	qc_calibrate(qcam);

	parport_release(qcam->pdev);
	
	printk(KERN_INFO "Connectix Quickcam on %s\n", qcam->pport->name);
	
	if(video_register_device(&qcam->vdev, VFL_TYPE_GRABBER, video_nr)==-1)
	{
		parport_unregister_device(qcam->pdev);
		kfree(qcam);
		return -ENODEV;
	}

	qcams[num_cams++] = qcam;

	return 0;
}

static void close_bwqcam(struct qcam_device *qcam)
{
	video_unregister_device(&qcam->vdev);
	parport_unregister_device(qcam->pdev);
	kfree(qcam);
}

/* The parport parameter controls which parports will be scanned.
 * Scanning all parports causes some printers to print a garbage page.
 *       -- March 14, 1999  Billy Donahue <[e-mail]> */
#ifdef MODULE
static char *parport[MAX_CAMS] = { NULL, };
module_param_array(parport, charp, NULL, 0);
#endif

static int accept_bwqcam(struct parport *port)
{
#ifdef MODULE
	int n;

	if (parport[0] && strncmp(parport[0], "auto", 4) != 0) {
		/* user gave parport parameters */
		for(n=0; parport[n] && n<MAX_CAMS; n++){
			char *ep;
			unsigned long r;
			r = simple_strtoul(parport[n], &ep, 0);
			if (ep == parport[n]) {
				printk(KERN_ERR
					"bw-qcam: bad port specifier \"%s\"\n",
					parport[n]);
				continue;
			}
			if (r == port->number)
				return 1;
		}
		return 0;
	}
#endif
	return 1;
}

static void bwqcam_attach(struct parport *port)
{
	if (accept_bwqcam(port))
		init_bwqcam(port);
}

static void bwqcam_detach(struct parport *port)
{
	int i;
	for (i = 0; i < num_cams; i++) {
		struct qcam_device *qcam = qcams[i];
		if (qcam && qcam->pdev->port == port) {
			qcams[i] = NULL;
			close_bwqcam(qcam);
		}
	}
}

static struct parport_driver bwqcam_driver = {
	.name	= "bw-qcam",
	.attach	= bwqcam_attach,
	.detach	= bwqcam_detach,
};

static void __exit exit_bw_qcams(void)
{
	parport_unregister_driver(&bwqcam_driver);
}

static int __init init_bw_qcams(void)
{
#ifdef MODULE
	/* Do some sanity checks on the module parameters. */
	if (maxpoll > 5000) {
		printk("Connectix Quickcam max-poll was above 5000. Using 5000.\n");
		maxpoll = 5000;
	}
	
	if (yieldlines < 1) {
		printk("Connectix Quickcam yieldlines was less than 1. Using 1.\n");
		yieldlines = 1;
	}
#endif
	return parport_register_driver(&bwqcam_driver);
}

module_init(init_bw_qcams);
module_exit(exit_bw_qcams);

MODULE_LICENSE("GPL");