/* Linux driver for Philips webcam   Decompression frontend.   (C) 1999-2003 Nemosoft Unv.   (C) 2004-2006 Luc Saillard (luc@saillard.org)   NOTE: this version of pwc is an unofficial (modified) release of pwc & pcwx   driver and thus may have bugs that are not present in the original version.   Please send bug reports and support requests to <luc@saillard.org>.   The decompression routines have been implemented by reverse-engineering the   Nemosoft binary pwcx module. Caveat emptor.   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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA   vim: set ts=8:  */#include <asm/current.h>#include <asm/types.h>#include "pwc.h"#include "pwc-uncompress.h"#include "pwc-dec1.h"#include "pwc-dec23.h"int pwc_decompress(struct pwc_device *pdev){	struct pwc_frame_buf *fbuf;	int n, line, col, stride;	void *yuv, *image;	u16 *src;	u16 *dsty, *dstu, *dstv;	if (pdev == NULL)		return -EFAULT;	fbuf = pdev->read_frame;	if (fbuf == NULL)		return -EFAULT;	image  = pdev->image_data;	image += pdev->images[pdev->fill_image].offset;	yuv = fbuf->data + pdev->frame_header_size;  /* Skip header */	/* Raw format; that's easy... */	if (pdev->vpalette == VIDEO_PALETTE_RAW)	{		struct pwc_raw_frame *raw_frame = image;		raw_frame->type = cpu_to_le16(pdev->type);		raw_frame->vbandlength = cpu_to_le16(pdev->vbandlength);			/* cmd_buf is always 4 bytes, but sometimes, only the			 * first 3 bytes is filled (Nala case). We can			 * determine this using the type of the webcam */		memcpy(raw_frame->cmd, pdev->cmd_buf, 4);		memcpy(raw_frame+1, yuv, pdev->frame_size);		return 0;	}	if (pdev->vbandlength == 0) {		/* Uncompressed mode.		 * We copy the data into the output buffer, using the viewport		 * size (which may be larger than the image size).		 * Unfortunately we have to do a bit of byte stuffing to get		 * the desired output format/size.		 *		 * We do some byte shuffling here to go from the		 * native format to YUV420P.		 */		src = (u16 *)yuv;		n = pdev->view.x * pdev->view.y;		/* offset in Y plane */		stride = pdev->view.x * pdev->offset.y + pdev->offset.x;		dsty = (u16 *)(image + stride);		/* offsets in U/V planes */		stride = pdev->view.x * pdev->offset.y / 4 + pdev->offset.x / 2;		dstu = (u16 *)(image + n +         stride);		dstv = (u16 *)(image + n + n / 4 + stride);		/* increment after each line */		stride = (pdev->view.x - pdev->image.x) / 2; /* u16 is 2 bytes */		for (line = 0; line < pdev->image.y; line++) {			for (col = 0; col < pdev->image.x; col += 4) {				*dsty++ = *src++;				*dsty++ = *src++;				if (line & 1)					*dstv++ = *src++;				else					*dstu++ = *src++;			}			dsty += stride;			if (line & 1)				dstv += (stride >> 1);			else				dstu += (stride >> 1);		}		return 0;	}	/*	 * Compressed;	 * the decompressor routines will write the data in planar format	 * immediately.	 */	if (pdev->vsize == PSZ_VGA && pdev->vframes == 5 && pdev->vsnapshot) {		PWC_ERROR("Mode Bayer is not supported for now\n");		/* flags |= PWCX_FLAG_BAYER; */		return -ENXIO; /* No such device or address: missing decompressor */	}	if (DEVICE_USE_CODEC1(pdev->type)) {		/* TODO & FIXME */		PWC_ERROR("This chipset is not supported for now\n");		return -ENXIO; /* No such device or address: missing decompressor */	} else {		pwc_dec23_decompress(pdev, yuv, image, PWCX_FLAG_PLANAR);	}	return 0;}/* vim: set cino= formatoptions=croql cindent shiftwidth=8 tabstop=8: */