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
pwc_decompress(struct pwc_device * pdev,struct pwc_frame_buf * fbuf)36 int 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.vb2_buf, 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.vb2_buf, 0,
59 pdev->frame_size + sizeof(struct pwc_raw_frame));
60 return 0;
61 }
62
63 vb2_set_plane_payload(&fbuf->vb.vb2_buf, 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