Commit 196e76e8 authored by David Rowe's avatar David Rowe Committed by Greg Kroah-Hartman
Browse files

Staging: echo: top bit patch 



This patch removes the need for the bit_operations.h include file which
can now be deleted.  It also contains some minor corrections to comments
(typos and alignment of ASCII formulas).  I have also removed some #if
lines that were not necessary.

I have tested the patch using a unit test module that runs in kernel
mode and have verified that the patched code gives identical results to
the previous version using a 8000 sample input sequence.  Let me know if
you want this unit test, it runs automatically when the module is
insmod-ed and outputs a go/no go result:

# insmod oslec.ko
# dmesg
[17191803.480000] oslec_test installed
[17191803.480000] Testing OSLEC with 128 taps (16 ms tail)
[17191803.496000] Oslec Unit Test PASSED! pass: 8000  fail: 0

Signed-off-by: default avatarDavid Rowe <david@rowetel.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent a3c0f0aa

drivers/staging/echo/TODO

+1 −1
Original line number Diff line number Diff line 
TODO:

	- handle bit_operations.h (merge in or make part of common code?)

	- send to lkml for review



Please send patches to Greg Kroah-Hartman <greg@kroah.com> and Cc: Steve

Underwood <steveu@coppice.org> and David Rowe <david@rowetel.com>

drivers/staging/echo/echo.c

+17 −10
Original line number Diff line number Diff line
@@ -106,7 +106,6 @@ 
#include <linux/module.h>

#include <linux/slab.h>



#include "bit_operations.h"

#include "echo.h"



#define MIN_TX_POWER_FOR_ADAPTION	64
@@ -221,6 +220,14 @@ static inline void lms_adapt_bg(struct oslec_state *ec, int clean, 
}

#endif



static __inline__ int top_bit(unsigned int bits)

{

	if (bits == 0)

	    return -1;

        else

	    return (int)fls((int32_t)bits)-1;

}



struct oslec_state *oslec_create(int len, int adaption_mode)

{

	struct oslec_state *ec;
@@ -347,7 +354,7 @@ int16_t oslec_update(struct oslec_state *ec, int16_t tx, int16_t rx) 
	/*

	 * Filter DC, 3dB point is 160Hz (I think), note 32 bit precision

	 * required otherwise values do not track down to 0. Zero at DC, Pole

	 * at (1-Beta) only real axis.  Some chip sets (like Si labs) don't

	 * at (1-Beta) on real axis.  Some chip sets (like Si labs) don't

	 * need this, but something like a $10 X100P card does.  Any DC really

	 * slows down convergence.

	 *
@@ -361,7 +368,7 @@ int16_t oslec_update(struct oslec_state *ec, int16_t tx, int16_t rx) 


	if (ec->adaption_mode & ECHO_CAN_USE_RX_HPF) {

		tmp = rx << 15;

#if 1



		/*

		 * Make sure the gain of the HPF is 1.0. This can still

		 * saturate a little under impulse conditions, and it might
@@ -371,7 +378,7 @@ int16_t oslec_update(struct oslec_state *ec, int16_t tx, int16_t rx) 
		 * the downstream processing.

		 */

		tmp -= (tmp >> 4);

#endif



		ec->rx_1 += -(ec->rx_1 >> DC_LOG2BETA) + tmp - ec->rx_2;



		/*
@@ -624,7 +631,7 @@ int16_t oslec_hpf_tx(struct oslec_state *ec, int16_t tx) 


	if (ec->adaption_mode & ECHO_CAN_USE_TX_HPF) {

		tmp = tx << 15;

#if 1



		/*

		 * Make sure the gain of the HPF is 1.0. The first can still

		 * saturate a little under impulse conditions, and it might
@@ -634,7 +641,7 @@ int16_t oslec_hpf_tx(struct oslec_state *ec, int16_t tx) 
		 * the downstream processing.

		 */

		tmp -= (tmp >> 4);

#endif



		ec->tx_1 += -(ec->tx_1 >> DC_LOG2BETA) + tmp - ec->tx_2;

		tmp1 = ec->tx_1 >> 15;

		if (tmp1 > 32767)

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