drivers/staging/vt6656/datarate.c - linux - Git at Google

 /*
  * Copyright (c) 1996, 2003 VIA Networking Technologies, Inc.
  * All rights reserved.
  *
  * 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.,
  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  *
  * File: datarate.c
  *
  * Purpose: Handles the auto fallback & data rates functions
  *
  * Author: Lyndon Chen
  *
  * Date: July 17, 2002
  *
  * Functions:
  *      RATEvParseMaxRate - Parsing the highest basic & support rate in rate field of frame
  *      RATEvTxRateFallBack - Rate fallback Algorithm Implementaion
  *      RATEuSetIE- Set rate IE field.
  *
  * Revision History:
  *
  */

 #include "tmacro.h"
 #include "mac.h"
 #include "80211mgr.h"
 #include "bssdb.h"
 #include "datarate.h"
 #include "card.h"
 #include "baseband.h"
 #include "rf.h"

 /* static int msglevel = MSG_LEVEL_DEBUG; */
 static int msglevel = MSG_LEVEL_INFO;
 static const u8 acbyIERate[MAX_RATE] = {0x02, 0x04, 0x0B, 0x16, 0x0C, 0x12, 0x18,
 	0x24, 0x30, 0x48, 0x60, 0x6C};

 #define AUTORATE_TXOK_CNT       0x0400
 #define AUTORATE_TXFAIL_CNT     0x0064
 #define AUTORATE_TIMEOUT        10

 void s_vResetCounter(PKnownNodeDB psNodeDBTable);

 void s_vResetCounter(PKnownNodeDB psNodeDBTable)
 {
 	u8 ii;

 	/* clear statistics counter for auto_rate */
 	for (ii = 0; ii <= MAX_RATE; ii++) {
 		psNodeDBTable->uTxOk[ii] = 0;
 		psNodeDBTable->uTxFail[ii] = 0;
 	}
 }

 /*+
  *
  * Routine Description:
  *      Rate fallback Algorithm Implementaion
  *
  * Parameters:
  *  In:
  *      pDevice         - Pointer to the adapter
  *      psNodeDBTable   - Pointer to Node Data Base
  *  Out:
  *      none
  *
  * Return Value: none
  *
 -*/
 #define AUTORATE_TXCNT_THRESHOLD        20
 #define AUTORATE_INC_THRESHOLD          30

 /*+
  *
  * Description:
  *      Get RateIdx from the value in SuppRates IE or ExtSuppRates IE
  *
  * Parameters:
  *  In:
  *      u8    - Rate value in SuppRates IE or ExtSuppRates IE
  *  Out:
  *      none
  *
  * Return Value: RateIdx
  *
 -*/
 u16 RATEwGetRateIdx(u8 byRate)
 {
 	u16 ii;

 	/* erase BasicRate flag */
 	byRate = byRate & 0x7F;

 	for (ii = 0; ii < MAX_RATE; ii++) {
 		if (acbyIERate[ii] == byRate)
 			return ii;
 	}
 	return 0;
 }

 /*+
  *
  * Description:
  *      Parsing the highest basic & support rate in rate field of frame.
  *
  * Parameters:
  *  In:
  *      pDevice         - Pointer to the adapter
  *      pItemRates      - Pointer to Rate field defined in 802.11 spec.
  *      pItemExtRates      - Pointer to Extended Rate field defined in 802.11 spec.
  *  Out:
  *      pwMaxBasicRate  - Maximum Basic Rate
  *      pwMaxSuppRate   - Maximum Supported Rate
  *      pbyTopCCKRate   - Maximum Basic Rate in CCK mode
  *      pbyTopOFDMRate  - Maximum Basic Rate in OFDM mode
  *
  * Return Value: none
  *
 -*/

 void RATEvParseMaxRate(struct vnt_private *pDevice,
 	PWLAN_IE_SUPP_RATES pItemRates, PWLAN_IE_SUPP_RATES pItemExtRates,
 	int bUpdateBasicRate, u16 *pwMaxBasicRate, u16 *pwMaxSuppRate,
 	u16 *pwSuppRate, u8 *pbyTopCCKRate, u8 *pbyTopOFDMRate)
 {
 	int ii;
 	u8 byHighSuppRate = 0, byRate = 0;
 	u16 wOldBasicRate = pDevice->wBasicRate;
 	u32 uRateLen;

 	if (pItemRates == NULL)
 		return;

 	*pwSuppRate = 0;
 	uRateLen = pItemRates->len;

 	DBG_PRT(MSG_LEVEL_DEBUG, KERN_INFO"ParseMaxRate Len: %d\n", uRateLen);
 	if (pDevice->byBBType != BB_TYPE_11B) {
 		if (uRateLen > WLAN_RATES_MAXLEN)
 			uRateLen = WLAN_RATES_MAXLEN;
 	} else {
 		if (uRateLen > WLAN_RATES_MAXLEN_11B)
 			uRateLen = WLAN_RATES_MAXLEN_11B;
 	}

 	for (ii = 0; ii < uRateLen; ii++) {
 		byRate = (u8)(pItemRates->abyRates[ii]);
 		if (WLAN_MGMT_IS_BASICRATE(byRate) &&
 				(bUpdateBasicRate == true)) {
 			/*
 			 * add to basic rate set, update pDevice->byTopCCKBasicRate and
 			 * pDevice->byTopOFDMBasicRate
 			 */
 			CARDbAddBasicRate((void *)pDevice, RATEwGetRateIdx(byRate));
 			DBG_PRT(MSG_LEVEL_DEBUG,
 				KERN_INFO"ParseMaxRate AddBasicRate: %d\n",
 				RATEwGetRateIdx(byRate));
 		}
 		byRate = (u8)(pItemRates->abyRates[ii]&0x7F);
 		if (byHighSuppRate == 0)
 			byHighSuppRate = byRate;
 		if (byRate > byHighSuppRate)
 			byHighSuppRate = byRate;
 		*pwSuppRate |= (1<<RATEwGetRateIdx(byRate));
 	}
 	if ((pItemExtRates != NULL) && (pItemExtRates->byElementID == WLAN_EID_EXTSUPP_RATES) &&
 			(pDevice->byBBType != BB_TYPE_11B)) {

 		unsigned int uExtRateLen = pItemExtRates->len;

 		if (uExtRateLen > WLAN_RATES_MAXLEN)
 			uExtRateLen = WLAN_RATES_MAXLEN;

 		for (ii = 0; ii < uExtRateLen; ii++) {
 			byRate = (u8)(pItemExtRates->abyRates[ii]);
 			/* select highest basic rate */
 			if (WLAN_MGMT_IS_BASICRATE(pItemExtRates->abyRates[ii])) {
 				/*
 				 * add to basic rate set, update pDevice->byTopCCKBasicRate and
 				 * pDevice->byTopOFDMBasicRate
 				 */
 				CARDbAddBasicRate((void *)pDevice, RATEwGetRateIdx(byRate));
 				DBG_PRT(MSG_LEVEL_DEBUG,
 						KERN_INFO"ParseMaxRate AddBasicRate: %d\n",
 						RATEwGetRateIdx(byRate));
 			}
 			byRate = (u8)(pItemExtRates->abyRates[ii]&0x7F);
 			if (byHighSuppRate == 0)
 				byHighSuppRate = byRate;
 			if (byRate > byHighSuppRate)
 				byHighSuppRate = byRate;
 			*pwSuppRate |= (1<<RATEwGetRateIdx(byRate));

 			/* DBG_PRN_GRP09(("ParseMaxRate : HighSuppRate: %d, %X\n",
 			 * RATEwGetRateIdx(byRate), byRate));
 			 */
 		}
 	}

 	if ((pDevice->byPacketType == PK_TYPE_11GB)
 			&& CARDbIsOFDMinBasicRate((void *)pDevice)) {
 		pDevice->byPacketType = PK_TYPE_11GA;
 	}

 	*pbyTopCCKRate = pDevice->byTopCCKBasicRate;
 	*pbyTopOFDMRate = pDevice->byTopOFDMBasicRate;
 	*pwMaxSuppRate = RATEwGetRateIdx(byHighSuppRate);
 	if ((pDevice->byPacketType == PK_TYPE_11B) || (pDevice->byPacketType == PK_TYPE_11GB))
 		*pwMaxBasicRate = pDevice->byTopCCKBasicRate;
 	else
 		*pwMaxBasicRate = pDevice->byTopOFDMBasicRate;
 	if (wOldBasicRate != pDevice->wBasicRate)
 		CARDvSetRSPINF((void *)pDevice, pDevice->byBBType);

 	DBG_PRT(MSG_LEVEL_DEBUG, KERN_INFO"Exit ParseMaxRate\n");
 }

 /*+
  *
  * Routine Description:
  *      Rate fallback Algorithm Implementaion
  *
  * Parameters:
  *  In:
  *      pDevice         - Pointer to the adapter
  *      psNodeDBTable   - Pointer to Node Data Base
  *  Out:
  *      none
  *
  * Return Value: none
  *
 -*/
 #define AUTORATE_TXCNT_THRESHOLD        20
 #define AUTORATE_INC_THRESHOLD          30

 void RATEvTxRateFallBack(struct vnt_private *pDevice,
 	PKnownNodeDB psNodeDBTable)
 {
 	struct vnt_manager *pMgmt = &pDevice->vnt_mgmt;
 	u16 wIdxDownRate = 0;
 	int ii;
 	int bAutoRate[MAX_RATE] = {true, true, true, true, false, false, true,
 					 true, true, true, true, true};
 	u32 dwThroughputTbl[MAX_RATE] = {10, 20, 55, 110, 60, 90, 120, 180,
 		240, 360, 480, 540};
 	u32 dwThroughput = 0;
 	u16 wIdxUpRate = 0;
 	u32 dwTxDiff = 0;

 	if (pMgmt->eScanState != WMAC_NO_SCANNING)
 		return; /* Don't do Fallback when scanning Channel */

 	psNodeDBTable->uTimeCount++;

 	if (psNodeDBTable->uTxFail[MAX_RATE] > psNodeDBTable->uTxOk[MAX_RATE])
 		dwTxDiff = psNodeDBTable->uTxFail[MAX_RATE] - psNodeDBTable->uTxOk[MAX_RATE];

 	if ((psNodeDBTable->uTxOk[MAX_RATE] < AUTORATE_TXOK_CNT) &&
 			(dwTxDiff < AUTORATE_TXFAIL_CNT) &&
 			(psNodeDBTable->uTimeCount < AUTORATE_TIMEOUT)) {
 		return;
 	}

 	if (psNodeDBTable->uTimeCount >= AUTORATE_TIMEOUT)
 		psNodeDBTable->uTimeCount = 0;

 	for (ii = 0; ii < MAX_RATE; ii++) {
 		if (psNodeDBTable->wSuppRate & (0x0001<<ii)) {
 			if (bAutoRate[ii] == true)
 				wIdxUpRate = (u16) ii;
 		} else {
 			bAutoRate[ii] = false;
 		}
 	}

 	for (ii = 0; ii <= psNodeDBTable->wTxDataRate; ii++) {
 		if ((psNodeDBTable->uTxOk[ii] != 0) ||
 				(psNodeDBTable->uTxFail[ii] != 0)) {
 			dwThroughputTbl[ii] *= psNodeDBTable->uTxOk[ii];
 			if (ii < RATE_11M)
 				psNodeDBTable->uTxFail[ii] *= 4;
 			dwThroughputTbl[ii] /= (psNodeDBTable->uTxOk[ii] + psNodeDBTable->uTxFail[ii]);
 		}
 		DBG_PRT(MSG_LEVEL_DEBUG, KERN_INFO"Rate %d,Ok: %d, Fail:%d, Throughput:%d\n",
 				ii, (int)psNodeDBTable->uTxOk[ii], (int)psNodeDBTable->uTxFail[ii], (int)dwThroughputTbl[ii]);
 	}
 	dwThroughput = dwThroughputTbl[psNodeDBTable->wTxDataRate];

 	wIdxDownRate = psNodeDBTable->wTxDataRate;
 	for (ii = psNodeDBTable->wTxDataRate; ii > 0;) {
 		ii--;
 		if ((dwThroughputTbl[ii] > dwThroughput) &&
 				(bAutoRate[ii] == true)) {
 			dwThroughput = dwThroughputTbl[ii];
 			wIdxDownRate = (u16) ii;
 		}
 	}
 	psNodeDBTable->wTxDataRate = wIdxDownRate;
 	if (psNodeDBTable->uTxOk[MAX_RATE]) {
 		if (psNodeDBTable->uTxOk[MAX_RATE] >
 				(psNodeDBTable->uTxFail[MAX_RATE] * 4)) {
 			psNodeDBTable->wTxDataRate = wIdxUpRate;
 		}
 	} else { /* adhoc, if uTxOk(total) == 0 & uTxFail(total) == 0 */
 		if (psNodeDBTable->uTxFail[MAX_RATE] == 0)
 			psNodeDBTable->wTxDataRate = wIdxUpRate;
 	}

 	if (pDevice->byBBType == BB_TYPE_11A) {
 		if (psNodeDBTable->wTxDataRate <= RATE_11M)
 			psNodeDBTable->wTxDataRate = RATE_6M;
 	}
 	DBG_PRT(MSG_LEVEL_DEBUG, KERN_INFO"uTxOk[MAX_RATE] %d, uTxFail[MAX_RATE]:%d\n", (int)psNodeDBTable->uTxOk[MAX_RATE], (int)psNodeDBTable->uTxFail[MAX_RATE]);
 	s_vResetCounter(psNodeDBTable);
 	DBG_PRT(MSG_LEVEL_DEBUG, KERN_INFO"Rate: %d, U:%d, D:%d\n", (int)psNodeDBTable->wTxDataRate, (int)wIdxUpRate, (int)wIdxDownRate);
 	return;
 }

 /*+
  *
  * Description:
  *    This routine is used to assemble available Rate IE.
  *
  * Parameters:
  *  In:
  *    pDevice
  *  Out:
  *
  * Return Value: None
  *
 -*/
 u8 RATEuSetIE(PWLAN_IE_SUPP_RATES pSrcRates, PWLAN_IE_SUPP_RATES pDstRates,
 		unsigned int uRateLen)
 {
 	unsigned int ii, uu, uRateCnt = 0;

 	if ((pSrcRates == NULL) || (pDstRates == NULL))
 		return 0;

 	if (pSrcRates->len == 0)
 		return 0;

 	for (ii = 0; ii < uRateLen; ii++) {
 		for (uu = 0; uu < pSrcRates->len; uu++) {
 			if ((pSrcRates->abyRates[uu] & 0x7F) == acbyIERate[ii]) {
 				pDstRates->abyRates[uRateCnt++] = pSrcRates->abyRates[uu];
 				break;
 			}
 		}
 	}
 	return (u8)uRateCnt;
 }
	/*
	* Copyright (c) 1996, 2003 VIA Networking Technologies, Inc.
	* All rights reserved.
	*
	* 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.,
	* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* File: datarate.c
	*
	* Purpose: Handles the auto fallback & data rates functions
	*
	* Author: Lyndon Chen
	*
	* Date: July 17, 2002
	*
	* Functions:
	* RATEvParseMaxRate - Parsing the highest basic & support rate in rate field of frame
	* RATEvTxRateFallBack - Rate fallback Algorithm Implementaion
	* RATEuSetIE- Set rate IE field.
	*
	* Revision History:
	*
	*/

	#include "tmacro.h"
	#include "mac.h"
	#include "80211mgr.h"
	#include "bssdb.h"
	#include "datarate.h"
	#include "card.h"
	#include "baseband.h"
	#include "rf.h"

	/* static int msglevel = MSG_LEVEL_DEBUG; */
	static int msglevel = MSG_LEVEL_INFO;
	static const u8 acbyIERate[MAX_RATE] = {0x02, 0x04, 0x0B, 0x16, 0x0C, 0x12, 0x18,
	0x24, 0x30, 0x48, 0x60, 0x6C};

	#define AUTORATE_TXOK_CNT 0x0400
	#define AUTORATE_TXFAIL_CNT 0x0064
	#define AUTORATE_TIMEOUT 10

	void s_vResetCounter(PKnownNodeDB psNodeDBTable);

	void s_vResetCounter(PKnownNodeDB psNodeDBTable)
	{
	u8 ii;

	/* clear statistics counter for auto_rate */
	for (ii = 0; ii <= MAX_RATE; ii++) {
	psNodeDBTable->uTxOk[ii] = 0;
	psNodeDBTable->uTxFail[ii] = 0;
	}
	}

	/*+
	*
	* Routine Description:
	* Rate fallback Algorithm Implementaion
	*
	* Parameters:
	* In:
	* pDevice - Pointer to the adapter
	* psNodeDBTable - Pointer to Node Data Base
	* Out:
	* none
	*
	* Return Value: none
	*
	-*/
	#define AUTORATE_TXCNT_THRESHOLD 20
	#define AUTORATE_INC_THRESHOLD 30

	/*+
	*
	* Description:
	* Get RateIdx from the value in SuppRates IE or ExtSuppRates IE
	*
	* Parameters:
	* In:
	* u8 - Rate value in SuppRates IE or ExtSuppRates IE
	* Out:
	* none
	*
	* Return Value: RateIdx
	*
	-*/
	u16 RATEwGetRateIdx(u8 byRate)
	{
	u16 ii;

	/* erase BasicRate flag */
	byRate = byRate & 0x7F;

	for (ii = 0; ii < MAX_RATE; ii++) {
	if (acbyIERate[ii] == byRate)
	return ii;
	}
	return 0;
	}

	/*+
	*
	* Description:
	* Parsing the highest basic & support rate in rate field of frame.
	*
	* Parameters:
	* In:
	* pDevice - Pointer to the adapter
	* pItemRates - Pointer to Rate field defined in 802.11 spec.
	* pItemExtRates - Pointer to Extended Rate field defined in 802.11 spec.
	* Out:
	* pwMaxBasicRate - Maximum Basic Rate
	* pwMaxSuppRate - Maximum Supported Rate
	* pbyTopCCKRate - Maximum Basic Rate in CCK mode
	* pbyTopOFDMRate - Maximum Basic Rate in OFDM mode
	*
	* Return Value: none
	*
	-*/

	void RATEvParseMaxRate(struct vnt_private *pDevice,
	PWLAN_IE_SUPP_RATES pItemRates, PWLAN_IE_SUPP_RATES pItemExtRates,
	int bUpdateBasicRate, u16 pwMaxBasicRate, u16 pwMaxSuppRate,
	u16 pwSuppRate, u8 pbyTopCCKRate, u8 *pbyTopOFDMRate)
	{
	int ii;
	u8 byHighSuppRate = 0, byRate = 0;
	u16 wOldBasicRate = pDevice->wBasicRate;
	u32 uRateLen;

	if (pItemRates == NULL)
	return;

	*pwSuppRate = 0;
	uRateLen = pItemRates->len;

	DBG_PRT(MSG_LEVEL_DEBUG, KERN_INFO"ParseMaxRate Len: %d\n", uRateLen);
	if (pDevice->byBBType != BB_TYPE_11B) {
	if (uRateLen > WLAN_RATES_MAXLEN)
	uRateLen = WLAN_RATES_MAXLEN;
	} else {
	if (uRateLen > WLAN_RATES_MAXLEN_11B)
	uRateLen = WLAN_RATES_MAXLEN_11B;
	}

	for (ii = 0; ii < uRateLen; ii++) {
	byRate = (u8)(pItemRates->abyRates[ii]);
	if (WLAN_MGMT_IS_BASICRATE(byRate) &&
	(bUpdateBasicRate == true)) {
	/*
	* add to basic rate set, update pDevice->byTopCCKBasicRate and
	* pDevice->byTopOFDMBasicRate
	*/
	CARDbAddBasicRate((void *)pDevice, RATEwGetRateIdx(byRate));
	DBG_PRT(MSG_LEVEL_DEBUG,
	KERN_INFO"ParseMaxRate AddBasicRate: %d\n",
	RATEwGetRateIdx(byRate));
	}
	byRate = (u8)(pItemRates->abyRates[ii]&0x7F);
	if (byHighSuppRate == 0)
	byHighSuppRate = byRate;
	if (byRate > byHighSuppRate)
	byHighSuppRate = byRate;
	*pwSuppRate \|= (1<<RATEwGetRateIdx(byRate));
	}
	if ((pItemExtRates != NULL) && (pItemExtRates->byElementID == WLAN_EID_EXTSUPP_RATES) &&
	(pDevice->byBBType != BB_TYPE_11B)) {

	unsigned int uExtRateLen = pItemExtRates->len;

	if (uExtRateLen > WLAN_RATES_MAXLEN)
	uExtRateLen = WLAN_RATES_MAXLEN;

	for (ii = 0; ii < uExtRateLen; ii++) {
	byRate = (u8)(pItemExtRates->abyRates[ii]);
	/* select highest basic rate */
	if (WLAN_MGMT_IS_BASICRATE(pItemExtRates->abyRates[ii])) {
	/*
	* add to basic rate set, update pDevice->byTopCCKBasicRate and
	* pDevice->byTopOFDMBasicRate
	*/
	CARDbAddBasicRate((void *)pDevice, RATEwGetRateIdx(byRate));
	DBG_PRT(MSG_LEVEL_DEBUG,
	KERN_INFO"ParseMaxRate AddBasicRate: %d\n",
	RATEwGetRateIdx(byRate));
	}
	byRate = (u8)(pItemExtRates->abyRates[ii]&0x7F);
	if (byHighSuppRate == 0)
	byHighSuppRate = byRate;
	if (byRate > byHighSuppRate)
	byHighSuppRate = byRate;
	*pwSuppRate \|= (1<<RATEwGetRateIdx(byRate));

	/* DBG_PRN_GRP09(("ParseMaxRate : HighSuppRate: %d, %X\n",
	* RATEwGetRateIdx(byRate), byRate));
	*/
	}
	}

	if ((pDevice->byPacketType == PK_TYPE_11GB)
	&& CARDbIsOFDMinBasicRate((void *)pDevice)) {
	pDevice->byPacketType = PK_TYPE_11GA;
	}

	*pbyTopCCKRate = pDevice->byTopCCKBasicRate;
	*pbyTopOFDMRate = pDevice->byTopOFDMBasicRate;
	*pwMaxSuppRate = RATEwGetRateIdx(byHighSuppRate);
	if ((pDevice->byPacketType == PK_TYPE_11B) \|\| (pDevice->byPacketType == PK_TYPE_11GB))
	*pwMaxBasicRate = pDevice->byTopCCKBasicRate;
	else
	*pwMaxBasicRate = pDevice->byTopOFDMBasicRate;
	if (wOldBasicRate != pDevice->wBasicRate)
	CARDvSetRSPINF((void *)pDevice, pDevice->byBBType);

	DBG_PRT(MSG_LEVEL_DEBUG, KERN_INFO"Exit ParseMaxRate\n");
	}

	/*+
	*
	* Routine Description:
	* Rate fallback Algorithm Implementaion
	*
	* Parameters:
	* In:
	* pDevice - Pointer to the adapter
	* psNodeDBTable - Pointer to Node Data Base
	* Out:
	* none
	*
	* Return Value: none
	*
	-*/
	#define AUTORATE_TXCNT_THRESHOLD 20
	#define AUTORATE_INC_THRESHOLD 30

	void RATEvTxRateFallBack(struct vnt_private *pDevice,
	PKnownNodeDB psNodeDBTable)
	{
	struct vnt_manager *pMgmt = &pDevice->vnt_mgmt;
	u16 wIdxDownRate = 0;
	int ii;
	int bAutoRate[MAX_RATE] = {true, true, true, true, false, false, true,
	true, true, true, true, true};
	u32 dwThroughputTbl[MAX_RATE] = {10, 20, 55, 110, 60, 90, 120, 180,
	240, 360, 480, 540};
	u32 dwThroughput = 0;
	u16 wIdxUpRate = 0;
	u32 dwTxDiff = 0;

	if (pMgmt->eScanState != WMAC_NO_SCANNING)
	return; /* Don't do Fallback when scanning Channel */

	psNodeDBTable->uTimeCount++;

	if (psNodeDBTable->uTxFail[MAX_RATE] > psNodeDBTable->uTxOk[MAX_RATE])
	dwTxDiff = psNodeDBTable->uTxFail[MAX_RATE] - psNodeDBTable->uTxOk[MAX_RATE];

	if ((psNodeDBTable->uTxOk[MAX_RATE] < AUTORATE_TXOK_CNT) &&
	(dwTxDiff < AUTORATE_TXFAIL_CNT) &&
	(psNodeDBTable->uTimeCount < AUTORATE_TIMEOUT)) {
	return;
	}

	if (psNodeDBTable->uTimeCount >= AUTORATE_TIMEOUT)
	psNodeDBTable->uTimeCount = 0;

	for (ii = 0; ii < MAX_RATE; ii++) {
	if (psNodeDBTable->wSuppRate & (0x0001<<ii)) {
	if (bAutoRate[ii] == true)
	wIdxUpRate = (u16) ii;
	} else {
	bAutoRate[ii] = false;
	}
	}

	for (ii = 0; ii <= psNodeDBTable->wTxDataRate; ii++) {
	if ((psNodeDBTable->uTxOk[ii] != 0) \|\|
	(psNodeDBTable->uTxFail[ii] != 0)) {
	dwThroughputTbl[ii] *= psNodeDBTable->uTxOk[ii];
	if (ii < RATE_11M)
	psNodeDBTable->uTxFail[ii] *= 4;
	dwThroughputTbl[ii] /= (psNodeDBTable->uTxOk[ii] + psNodeDBTable->uTxFail[ii]);
	}
	DBG_PRT(MSG_LEVEL_DEBUG, KERN_INFO"Rate %d,Ok: %d, Fail:%d, Throughput:%d\n",
	ii, (int)psNodeDBTable->uTxOk[ii], (int)psNodeDBTable->uTxFail[ii], (int)dwThroughputTbl[ii]);
	}
	dwThroughput = dwThroughputTbl[psNodeDBTable->wTxDataRate];

	wIdxDownRate = psNodeDBTable->wTxDataRate;
	for (ii = psNodeDBTable->wTxDataRate; ii > 0;) {
	ii--;
	if ((dwThroughputTbl[ii] > dwThroughput) &&
	(bAutoRate[ii] == true)) {
	dwThroughput = dwThroughputTbl[ii];
	wIdxDownRate = (u16) ii;
	}
	}
	psNodeDBTable->wTxDataRate = wIdxDownRate;
	if (psNodeDBTable->uTxOk[MAX_RATE]) {
	if (psNodeDBTable->uTxOk[MAX_RATE] >
	(psNodeDBTable->uTxFail[MAX_RATE] * 4)) {
	psNodeDBTable->wTxDataRate = wIdxUpRate;
	}
	} else { /* adhoc, if uTxOk(total) == 0 & uTxFail(total) == 0 */
	if (psNodeDBTable->uTxFail[MAX_RATE] == 0)
	psNodeDBTable->wTxDataRate = wIdxUpRate;
	}

	if (pDevice->byBBType == BB_TYPE_11A) {
	if (psNodeDBTable->wTxDataRate <= RATE_11M)
	psNodeDBTable->wTxDataRate = RATE_6M;
	}
	DBG_PRT(MSG_LEVEL_DEBUG, KERN_INFO"uTxOk[MAX_RATE] %d, uTxFail[MAX_RATE]:%d\n", (int)psNodeDBTable->uTxOk[MAX_RATE], (int)psNodeDBTable->uTxFail[MAX_RATE]);
	s_vResetCounter(psNodeDBTable);
	DBG_PRT(MSG_LEVEL_DEBUG, KERN_INFO"Rate: %d, U:%d, D:%d\n", (int)psNodeDBTable->wTxDataRate, (int)wIdxUpRate, (int)wIdxDownRate);
	return;
	}

	/*+
	*
	* Description:
	* This routine is used to assemble available Rate IE.
	*
	* Parameters:
	* In:
	* pDevice
	* Out:
	*
	* Return Value: None
	*
	-*/
	u8 RATEuSetIE(PWLAN_IE_SUPP_RATES pSrcRates, PWLAN_IE_SUPP_RATES pDstRates,
	unsigned int uRateLen)
	{
	unsigned int ii, uu, uRateCnt = 0;

	if ((pSrcRates == NULL) \|\| (pDstRates == NULL))
	return 0;

	if (pSrcRates->len == 0)
	return 0;

	for (ii = 0; ii < uRateLen; ii++) {
	for (uu = 0; uu < pSrcRates->len; uu++) {
	if ((pSrcRates->abyRates[uu] & 0x7F) == acbyIERate[ii]) {
	pDstRates->abyRates[uRateCnt++] = pSrcRates->abyRates[uu];
	break;
	}
	}
	}
	return (u8)uRateCnt;
	}