52 lines
		
	
	
	
		
			1.5 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
		
		
			
		
	
	
			52 lines
		
	
	
	
		
			1.5 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
|   | /*
 | ||
|  |  * SN9C2028 common functions | ||
|  |  * | ||
|  |  * Copyright (C) 2009 Theodore Kilgore <kilgota@auburn,edu> | ||
|  |  * | ||
|  |  * Based closely upon the file gspca/pac_common.h | ||
|  |  * | ||
|  |  * 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 | ||
|  |  * | ||
|  |  */ | ||
|  | 
 | ||
|  | static const unsigned char sn9c2028_sof_marker[5] = | ||
|  | 	{ 0xff, 0xff, 0x00, 0xc4, 0xc4 }; | ||
|  | 
 | ||
|  | static unsigned char *sn9c2028_find_sof(struct gspca_dev *gspca_dev, | ||
|  | 					unsigned char *m, int len) | ||
|  | { | ||
|  | 	struct sd *sd = (struct sd *) gspca_dev; | ||
|  | 	int i; | ||
|  | 
 | ||
|  | 	/* Search for the SOF marker (fixed part) in the header */ | ||
|  | 	for (i = 0; i < len; i++) { | ||
|  | 		if (m[i] == sn9c2028_sof_marker[sd->sof_read]) { | ||
|  | 			sd->sof_read++; | ||
|  | 			if (sd->sof_read == sizeof(sn9c2028_sof_marker)) { | ||
|  | 				PDEBUG(D_FRAM, | ||
|  | 					"SOF found, bytes to analyze: %u." | ||
|  | 					" Frame starts at byte #%u", | ||
|  | 					len, i + 1); | ||
|  | 				sd->sof_read = 0; | ||
|  | 				return m + i + 1; | ||
|  | 			} | ||
|  | 		} else { | ||
|  | 			sd->sof_read = 0; | ||
|  | 		} | ||
|  | 	} | ||
|  | 
 | ||
|  | 	return NULL; | ||
|  | } |