1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* Linux driver for Philips webcam |
3 | Decompression frontend. |
4 | (C) 1999-2003 Nemosoft Unv. |
5 | (C) 2004-2006 Luc Saillard (luc@saillard.org) |
6 | |
7 | NOTE: this version of pwc is an unofficial (modified) release of pwc & pcwx |
8 | driver and thus may have bugs that are not present in the original version. |
9 | Please send bug reports and support requests to <luc@saillard.org>. |
10 | The decompression routines have been implemented by reverse-engineering the |
11 | Nemosoft binary pwcx module. Caveat emptor. |
12 | */ |
13 | |
14 | #include <asm/current.h> |
15 | #include <asm/types.h> |
16 | |
17 | #include "pwc.h" |
18 | #include "pwc-dec1.h" |
19 | #include "pwc-dec23.h" |
20 | |
21 | int pwc_decompress(struct pwc_device *pdev, struct pwc_frame_buf *fbuf) |
22 | { |
23 | int n, line, col; |
24 | void *yuv, *image; |
25 | u16 *src; |
26 | u16 *dsty, *dstu, *dstv; |
27 | |
28 | image = vb2_plane_vaddr(vb: &fbuf->vb.vb2_buf, plane_no: 0); |
29 | |
30 | yuv = fbuf->data + pdev->frame_header_size; /* Skip header */ |
31 | |
32 | /* Raw format; that's easy... */ |
33 | if (pdev->pixfmt != V4L2_PIX_FMT_YUV420) |
34 | { |
35 | struct pwc_raw_frame *raw_frame = image; |
36 | raw_frame->type = cpu_to_le16(pdev->type); |
37 | raw_frame->vbandlength = cpu_to_le16(pdev->vbandlength); |
38 | /* cmd_buf is always 4 bytes, but sometimes, only the |
39 | * first 3 bytes is filled (Nala case). We can |
40 | * determine this using the type of the webcam */ |
41 | memcpy(raw_frame->cmd, pdev->cmd_buf, 4); |
42 | memcpy(raw_frame->rawframe, yuv, pdev->frame_size); |
43 | vb2_set_plane_payload(vb: &fbuf->vb.vb2_buf, plane_no: 0, |
44 | struct_size(raw_frame, rawframe, pdev->frame_size)); |
45 | return 0; |
46 | } |
47 | |
48 | vb2_set_plane_payload(vb: &fbuf->vb.vb2_buf, plane_no: 0, |
49 | size: pdev->width * pdev->height * 3 / 2); |
50 | |
51 | if (pdev->vbandlength == 0) { |
52 | /* Uncompressed mode. |
53 | * |
54 | * We do some byte shuffling here to go from the |
55 | * native format to YUV420P. |
56 | */ |
57 | src = (u16 *)yuv; |
58 | n = pdev->width * pdev->height; |
59 | dsty = (u16 *)(image); |
60 | dstu = (u16 *)(image + n); |
61 | dstv = (u16 *)(image + n + n / 4); |
62 | |
63 | for (line = 0; line < pdev->height; line++) { |
64 | for (col = 0; col < pdev->width; col += 4) { |
65 | *dsty++ = *src++; |
66 | *dsty++ = *src++; |
67 | if (line & 1) |
68 | *dstv++ = *src++; |
69 | else |
70 | *dstu++ = *src++; |
71 | } |
72 | } |
73 | |
74 | return 0; |
75 | } |
76 | |
77 | /* |
78 | * Compressed; |
79 | * the decompressor routines will write the data in planar format |
80 | * immediately. |
81 | */ |
82 | if (DEVICE_USE_CODEC1(pdev->type)) { |
83 | |
84 | /* TODO & FIXME */ |
85 | PWC_ERROR("This chipset is not supported for now\n" ); |
86 | return -ENXIO; /* No such device or address: missing decompressor */ |
87 | |
88 | } else { |
89 | pwc_dec23_decompress(pdev, src: yuv, dst: image); |
90 | } |
91 | return 0; |
92 | } |
93 | |