1/* Linux driver for Philips webcam
2   Decompression frontend.
3   (C) 1999-2003 Nemosoft Unv.
4   (C) 2004-2006 Luc Saillard (luc@saillard.org)
5
6   NOTE: this version of pwc is an unofficial (modified) release of pwc & pcwx
7   driver and thus may have bugs that are not present in the original version.
8   Please send bug reports and support requests to <luc@saillard.org>.
9   The decompression routines have been implemented by reverse-engineering the
10   Nemosoft binary pwcx module. Caveat emptor.
11
12   This program is free software; you can redistribute it and/or modify
13   it under the terms of the GNU General Public License as published by
14   the Free Software Foundation; either version 2 of the License, or
15   (at your option) any later version.
16
17   This program is distributed in the hope that it will be useful,
18   but WITHOUT ANY WARRANTY; without even the implied warranty of
19   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
20   GNU General Public License for more details.
21
22   You should have received a copy of the GNU General Public License
23   along with this program; if not, write to the Free Software
24   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
25
26   vim: set ts=8:
27*/
28
29#include <asm/current.h>
30#include <asm/types.h>
31
32#include "pwc.h"
33#include "pwc-dec1.h"
34#include "pwc-dec23.h"
35
36int pwc_decompress(struct pwc_device *pdev, struct pwc_frame_buf *fbuf)
37{
38	int n, line, col;
39	void *yuv, *image;
40	u16 *src;
41	u16 *dsty, *dstu, *dstv;
42
43	image = vb2_plane_vaddr(&fbuf->vb, 0);
44
45	yuv = fbuf->data + pdev->frame_header_size;  /* Skip header */
46
47	/* Raw format; that's easy... */
48	if (pdev->pixfmt != V4L2_PIX_FMT_YUV420)
49	{
50		struct pwc_raw_frame *raw_frame = image;
51		raw_frame->type = cpu_to_le16(pdev->type);
52		raw_frame->vbandlength = cpu_to_le16(pdev->vbandlength);
53			/* cmd_buf is always 4 bytes, but sometimes, only the
54			 * first 3 bytes is filled (Nala case). We can
55			 * determine this using the type of the webcam */
56		memcpy(raw_frame->cmd, pdev->cmd_buf, 4);
57		memcpy(raw_frame+1, yuv, pdev->frame_size);
58		vb2_set_plane_payload(&fbuf->vb, 0,
59			pdev->frame_size + sizeof(struct pwc_raw_frame));
60		return 0;
61	}
62
63	vb2_set_plane_payload(&fbuf->vb, 0,
64			      pdev->width * pdev->height * 3 / 2);
65
66	if (pdev->vbandlength == 0) {
67		/* Uncompressed mode.
68		 *
69		 * We do some byte shuffling here to go from the
70		 * native format to YUV420P.
71		 */
72		src = (u16 *)yuv;
73		n = pdev->width * pdev->height;
74		dsty = (u16 *)(image);
75		dstu = (u16 *)(image + n);
76		dstv = (u16 *)(image + n + n / 4);
77
78		for (line = 0; line < pdev->height; line++) {
79			for (col = 0; col < pdev->width; col += 4) {
80				*dsty++ = *src++;
81				*dsty++ = *src++;
82				if (line & 1)
83					*dstv++ = *src++;
84				else
85					*dstu++ = *src++;
86			}
87		}
88
89		return 0;
90	}
91
92	/*
93	 * Compressed;
94	 * the decompressor routines will write the data in planar format
95	 * immediately.
96	 */
97	if (DEVICE_USE_CODEC1(pdev->type)) {
98
99		/* TODO & FIXME */
100		PWC_ERROR("This chipset is not supported for now\n");
101		return -ENXIO; /* No such device or address: missing decompressor */
102
103	} else {
104		pwc_dec23_decompress(pdev, yuv, image);
105	}
106	return 0;
107}
108