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	The code is clean, there are users of it, so it doesn't belong in staging anymore, move it to drivers/misc/. Cc: Steve Underwood <steveu@coppice.org> Cc: David Rowe <david@rowetel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
		
			
				
	
	
		
			94 lines
		
	
	
	
		
			2.8 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			94 lines
		
	
	
	
		
			2.8 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/*
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 *  OSLEC - A line echo canceller.  This code is being developed
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 *          against and partially complies with G168. Using code from SpanDSP
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 *
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 * Written by Steve Underwood <steveu@coppice.org>
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 *         and David Rowe <david_at_rowetel_dot_com>
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 *
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 * Copyright (C) 2001 Steve Underwood and 2007-2008 David Rowe
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 *
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 * All rights reserved.
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 *
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 * This program is free software; you can redistribute it and/or modify
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 * it under the terms of the GNU General Public License version 2, as
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 * published by the Free Software Foundation.
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 *
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 * This program is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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 * GNU General Public License for more details.
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 *
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 * You should have received a copy of the GNU General Public License
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 * along with this program; if not, write to the Free Software
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 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
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 *
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 */
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#ifndef __OSLEC_H
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#define __OSLEC_H
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/* Mask bits for the adaption mode */
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#define ECHO_CAN_USE_ADAPTION	0x01
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#define ECHO_CAN_USE_NLP	0x02
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#define ECHO_CAN_USE_CNG	0x04
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#define ECHO_CAN_USE_CLIP	0x08
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#define ECHO_CAN_USE_TX_HPF	0x10
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#define ECHO_CAN_USE_RX_HPF	0x20
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#define ECHO_CAN_DISABLE	0x40
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/**
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 * oslec_state: G.168 echo canceller descriptor.
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 *
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 * This defines the working state for a line echo canceller.
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 */
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struct oslec_state;
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/**
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 * oslec_create - Create a voice echo canceller context.
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 * @len: The length of the canceller, in samples.
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 * @return: The new canceller context, or NULL if the canceller could not be
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 * created.
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 */
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struct oslec_state *oslec_create(int len, int adaption_mode);
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/**
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 * oslec_free - Free a voice echo canceller context.
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 * @ec: The echo canceller context.
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 */
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void oslec_free(struct oslec_state *ec);
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/**
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 * oslec_flush - Flush (reinitialise) a voice echo canceller context.
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 * @ec: The echo canceller context.
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 */
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void oslec_flush(struct oslec_state *ec);
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/**
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 * oslec_adaption_mode - set the adaption mode of a voice echo canceller context.
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 * @ec The echo canceller context.
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 * @adaption_mode: The mode.
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 */
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void oslec_adaption_mode(struct oslec_state *ec, int adaption_mode);
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void oslec_snapshot(struct oslec_state *ec);
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/**
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 * oslec_update: Process a sample through a voice echo canceller.
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 * @ec: The echo canceller context.
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 * @tx: The transmitted audio sample.
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 * @rx: The received audio sample.
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 *
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 * The return value is the clean (echo cancelled) received sample.
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 */
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int16_t oslec_update(struct oslec_state *ec, int16_t tx, int16_t rx);
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/**
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 * oslec_hpf_tx: Process to high pass filter the tx signal.
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 * @ec: The echo canceller context.
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 * @tx: The transmitted auio sample.
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 *
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 * The return value is the HP filtered transmit sample, send this to your D/A.
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 */
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int16_t oslec_hpf_tx(struct oslec_state *ec, int16_t tx);
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#endif /* __OSLEC_H */
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