xref: /linux/drivers/media/usb/pwc/pwc-misc.c (revision c0c914eca7f251c70facc37dfebeaf176601918d)
1 /* Linux driver for Philips webcam
2    Various miscellaneous functions and tables.
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 
27 
28 #include "pwc.h"
29 
30 const int pwc_image_sizes[PSZ_MAX][2] =
31 {
32 	{ 128,  96 }, /* sqcif */
33 	{ 160, 120 }, /* qsif */
34 	{ 176, 144 }, /* qcif */
35 	{ 320, 240 }, /* sif */
36 	{ 352, 288 }, /* cif */
37 	{ 640, 480 }, /* vga */
38 };
39 
40 /* x,y -> PSZ_ */
41 int pwc_get_size(struct pwc_device *pdev, int width, int height)
42 {
43 	int i;
44 
45 	/* Find the largest size supported by the camera that fits into the
46 	   requested size. */
47 	for (i = PSZ_MAX - 1; i >= 0; i--) {
48 		if (!(pdev->image_mask & (1 << i)))
49 			continue;
50 
51 		if (pwc_image_sizes[i][0] <= width &&
52 		    pwc_image_sizes[i][1] <= height)
53 			return i;
54 	}
55 
56 	/* No mode found, return the smallest mode we have */
57 	for (i = 0; i < PSZ_MAX; i++) {
58 		if (pdev->image_mask & (1 << i))
59 			return i;
60 	}
61 
62 	/* Never reached there always is atleast one supported mode */
63 	return 0;
64 }
65 
66 /* initialize variables depending on type and decompressor */
67 void pwc_construct(struct pwc_device *pdev)
68 {
69 	if (DEVICE_USE_CODEC1(pdev->type)) {
70 
71 		pdev->image_mask = 1 << PSZ_SQCIF | 1 << PSZ_QCIF | 1 << PSZ_CIF;
72 		pdev->vcinterface = 2;
73 		pdev->vendpoint = 4;
74 		pdev->frame_header_size = 0;
75 		pdev->frame_trailer_size = 0;
76 
77 	} else if (DEVICE_USE_CODEC3(pdev->type)) {
78 
79 		pdev->image_mask = 1 << PSZ_QSIF | 1 << PSZ_SIF | 1 << PSZ_VGA;
80 		pdev->vcinterface = 3;
81 		pdev->vendpoint = 5;
82 		pdev->frame_header_size = TOUCAM_HEADER_SIZE;
83 		pdev->frame_trailer_size = TOUCAM_TRAILER_SIZE;
84 
85 	} else /* if (DEVICE_USE_CODEC2(pdev->type)) */ {
86 
87 		pdev->image_mask = 1 << PSZ_SQCIF | 1 << PSZ_QSIF | 1 << PSZ_QCIF | 1 << PSZ_SIF | 1 << PSZ_CIF | 1 << PSZ_VGA;
88 		pdev->vcinterface = 3;
89 		pdev->vendpoint = 4;
90 		pdev->frame_header_size = 0;
91 		pdev->frame_trailer_size = 0;
92 	}
93 }
94