mlme.c

TP Link 321 Linux Driver

	if (pAd->Mlme.CntlMachine.CurrState == CNTL_IDLE)
	{
		DBGPRINT(RT_DEBUG_TRACE, "MMCHK - Driver auto scan\n");
		MlmeEnqueue(pAd, 
					MLME_CNTL_STATE_MACHINE, 
					OID_802_11_BSSID_LIST_SCAN, 
					0, 
					NULL);
		RTUSBMlmeUp(pAd);
	}
}
	
VOID MlmeAutoRecoverNetwork(
	IN PRTMP_ADAPTER pAd)
{
	// check CntlMachine.CurrState to avoid collision with NDIS SetOID request
	if (pAd->Mlme.CntlMachine.CurrState == CNTL_IDLE)
	{
		NDIS_802_11_SSID OidSsid;
		OidSsid.SsidLength = pAd->PortCfg.SsidLen;
		NdisMoveMemory(OidSsid.Ssid, pAd->PortCfg.Ssid, pAd->PortCfg.SsidLen);

		DBGPRINT(RT_DEBUG_TRACE, "MMCHK - Driver auto recovering network - %s\n", pAd->PortCfg.Ssid);

		MlmeEnqueue(pAd, 
					MLME_CNTL_STATE_MACHINE, 
					OID_802_11_SSID, 
					sizeof(NDIS_802_11_SSID), 
					&OidSsid);
	   RTUSBMlmeUp(pAd);
	}

}

//2007/11/09:KH replace the original MlmeAutoReconnectLastSSID
VOID MlmeAutoReconnectLastSSID(
	IN PRTMP_ADAPTER pAd)
{
	// check CntlMachine.CurrState to avoid collision with NDIS SetOID request
	MLME_SCAN_REQ_STRUCT       ScanReq;
	ULONG Now= pAd->Mlme.Now32;
    if ((pAd->Mlme.CntlMachine.CurrState == CNTL_IDLE) && ((pAd->PortCfg.LastScanTime + (10*HZ)) >= Now))		// BUG (10 sec)
    {
	if (pAd->Mlme.CntlMachine.CurrState == CNTL_IDLE &&
		(MlmeValidateSSID(pAd->MlmeAux.AutoReconnectSsid, pAd->MlmeAux.AutoReconnectSsidLen) == TRUE))
	{
		NDIS_802_11_SSID OidSsid;
		OidSsid.SsidLength = pAd->MlmeAux.AutoReconnectSsidLen;
		NdisMoveMemory(OidSsid.Ssid, pAd->MlmeAux.AutoReconnectSsid, pAd->MlmeAux.AutoReconnectSsidLen);

		DBGPRINT(RT_DEBUG_TRACE, "Driver auto reconnect to last OID_802_11_SSID setting - %s\n", pAd->MlmeAux.AutoReconnectSsid);

	     	/* carella modify: if no SSID, sta should not try to connect AP in scan table */
			if(OidSsid.SsidLength)
			{
		MlmeEnqueue(pAd, 
					MLME_CNTL_STATE_MACHINE, 
					OID_802_11_SSID, 
					sizeof(NDIS_802_11_SSID), 
					&OidSsid);
		RTUSBMlmeUp(pAd);
	                 }
            }
      }
      else if ((pAd->PortCfg.LastScanTime + (10*HZ)) < Now)								
      {
		// check CntlMachine.CurrState to avoid collision with NDIS SetOID request
		DBGPRINT(RT_DEBUG_TRACE, "MMCHK - FastRoaming, No eligable entry, try new scan!\n");

		pAd->PortCfg.ScanCnt = 2;
		pAd->PortCfg.LastScanTime = Now;

		ScanParmFill(pAd, &ScanReq, pAd->MlmeAux.AutoReconnectSsid, pAd->MlmeAux.AutoReconnectSsidLen, BSS_ANY, SCAN_ACTIVE);
		
		MlmeEnqueue(pAd, SYNC_STATE_MACHINE, MT2_MLME_SCAN_REQ, 
					sizeof(MLME_SCAN_REQ_STRUCT), &ScanReq);
                RTUSBMlmeUp(pAd);
		pAd->Mlme.CntlMachine.CurrState = CNTL_WAIT_OID_LIST_SCAN;
	}
}

/*
	==========================================================================
	Validate SSID for connection try and rescan purpose
	Valid SSID will have visible chars only.
	The valid length is from 0 to 32.
	==========================================================================
 */
BOOLEAN	MlmeValidateSSID(
	IN PUCHAR	pSsid,
	IN UCHAR	SsidLen)
{
	int	index;

	if (SsidLen > MAX_LEN_OF_SSID)
		return (FALSE);

	// Check each character value
	for (index = 0; index < SsidLen; index++)
	{
		if (pSsid[index] < 0x20)
			return (FALSE);
	}

	// All checked
	return (TRUE);
}

/*
	==========================================================================
	Description:
		This routine checks if there're other APs out there capable for
		roaming. Caller should call this routine only when Link up in INFRA mode
		and channel quality is below CQI_GOOD_THRESHOLD.
		
	Output:
	==========================================================================
 */
VOID MlmeCheckForRoaming(
	IN PRTMP_ADAPTER pAd,
	IN ULONG	Now32)
{
	USHORT	   i;
	BSS_TABLE  *pRoamTab = &pAd->MlmeAux.RoamTab;
	BSS_ENTRY  *pBss;

	DBGPRINT(RT_DEBUG_TRACE, "==> MlmeCheckForRoaming::pAd->ScanTab.BssNr = %d\n", pAd->ScanTab.BssNr);
	// put all roaming candidates into RoamTab, and sort in RSSI order
	BssTableInit(pRoamTab);
	for (i = 0; i < pAd->ScanTab.BssNr; i++)
	{
		pBss = &pAd->ScanTab.BssEntry[i];
		
		DBGPRINT(RT_DEBUG_TRACE, "MlmeCheckForRoaming::pBss->LastBeaconRxTime = %d\n", pBss->LastBeaconRxTime);
		if ((pBss->LastBeaconRxTime + BEACON_LOST_TIME) < Now32)
		{
			DBGPRINT(RT_DEBUG_TRACE, "1: AP disappear::Now32 = %d\n", Now32);
			continue;	 // AP disappear
		}
		if (pBss->Rssi <= RSSI_THRESHOLD_FOR_ROAMING)
		{
			DBGPRINT(RT_DEBUG_TRACE, "2: RSSI too weak::Rssi[%d] - RSSI_THRESHOLD_FOR_ROAMING[%d]\n", pBss->Rssi, RSSI_THRESHOLD_FOR_ROAMING);
			continue;	 // RSSI too weak. forget it.
		}
		if (MAC_ADDR_EQUAL(pBss->Bssid, pAd->PortCfg.Bssid))
		{
			DBGPRINT(RT_DEBUG_TRACE, "3: skip current AP\n");
			continue;	 // skip current AP
		}
		if (!SSID_EQUAL(pBss->Ssid, pBss->SsidLen, pAd->PortCfg.Ssid, pAd->PortCfg.SsidLen))
		{
			DBGPRINT(RT_DEBUG_TRACE, "4: skip different SSID\n");
			continue;	 // skip different SSID
		}
		if (pBss->Rssi < (pAd->PortCfg.LastRssi + RSSI_DELTA))
		{
			DBGPRINT(RT_DEBUG_TRACE, "5: only AP with stronger RSSI is eligible for roaming\n");
			continue;	 // only AP with stronger RSSI is eligible for roaming
		}
		// AP passing all above rules is put into roaming candidate table		 
		NdisMoveMemory(&pRoamTab->BssEntry[pRoamTab->BssNr], pBss, sizeof(BSS_ENTRY));
		pRoamTab->BssNr += 1;
	}

	if (pRoamTab->BssNr > 0)
	{
		// check CntlMachine.CurrState to avoid collision with NDIS SetOID request
		if (pAd->Mlme.CntlMachine.CurrState == CNTL_IDLE)
		{
			pAd->RalinkCounters.PoorCQIRoamingCount ++;
			DBGPRINT(RT_DEBUG_TRACE, "MMCHK - Roaming attempt #%d\n", pAd->RalinkCounters.PoorCQIRoamingCount);
			MlmeEnqueue(pAd, MLME_CNTL_STATE_MACHINE, MT2_MLME_ROAMING_REQ, 0, NULL);
			RTUSBMlmeUp(pAd);
		}
	}
	DBGPRINT(RT_DEBUG_TRACE, "<== MlmeCheckForRoaming(# of candidate= %d)\n",pRoamTab->BssNr);	 
}

/*
	==========================================================================
	Description:
		This routine checks if there're other APs out there capable for
		roaming. Caller should call this routine only when link up in INFRA mode
		and channel quality is below CQI_GOOD_THRESHOLD.

	Output:
	==========================================================================
 */
VOID MlmeCheckForFastRoaming(
	IN	PRTMP_ADAPTER	pAd,
	IN	ULONG			Now)
{
	USHORT     i;
	BSS_TABLE  *pRoamTab = &pAd->MlmeAux.RoamTab;
	BSS_ENTRY  *pBss;
        MLME_SCAN_REQ_STRUCT       ScanReq;	
	DBGPRINT(RT_DEBUG_TRACE, "==> MlmeCheckForFastRoaming\n");
	//
        // If Scan talbe is fresh within 10 sec, then we can select the AP with the best RSSI
        // Otherwise refresh this scan table.
        //
        //KH modified time-unit from jiffies to HZ
        if ((pAd->Mlme.CntlMachine.CurrState == CNTL_IDLE) && ((pAd->PortCfg.LastScanTime + 10 * HZ) >= Now))
        {
           BssTableInit(pRoamTab);
           // put all roaming candidates into RoamTab, and sort in RSSI order
	
	for (i = 0; i < pAd->ScanTab.BssNr; i++)
	{
		pBss = &pAd->ScanTab.BssEntry[i];

		/*2007/11/05:KH replace the line"if ((pBss->Rssi <= 45) && (pBss->Channel == pAd->PortCfg.Channel))" to enable the roaming between different channels.
		*/
			if(pBss->Rssi<=45)
			continue;    // RSSI too weak. forget it.
		if (MAC_ADDR_EQUAL(pBss->Bssid, pAd->PortCfg.Bssid))
			continue;    // skip current AP

                //2007/12/20:correct hidden bugs 
		if (!SSID_EQUAL(pBss->Ssid, pBss->SsidLen, pAd->PortCfg.Ssid, pAd->PortCfg.SsidLen) &&pBss->SsidLen>0&&pBss->Ssid[0]!=0 )
			continue;    // skip different SSID
		if (pBss->Rssi < (pAd->PortCfg.LastRssi + RSSI_DELTA)) 
			continue;    // skip AP without better RSSI
		
		DBGPRINT(RT_DEBUG_TRACE, "LastRssi = %d, pBss->Rssi = %d\n", pAd->PortCfg.LastRssi, pBss->Rssi);
		// AP passing all above rules is put into roaming candidate table        
		NdisMoveMemory(&pRoamTab->BssEntry[pRoamTab->BssNr], pBss, sizeof(BSS_ENTRY));
	
                 //2007/12/06:KH add to fix roaming with hidden SSID
		if(pBss->SsidLen==0||pBss->Ssid[0]==0)
			{
				DBGPRINT(RT_DEBUG_TRACE, "Roaming With NULL SSID and BSSID[#%d]=%s", pRoamTab->BssNr,pBss->Bssid);
				pRoamTab->BssEntry[pRoamTab->BssNr].SsidLen=pAd->PortCfg.SsidLen;
				NdisMoveMemory(pRoamTab->BssEntry[pRoamTab->BssNr].Ssid, pAd->PortCfg.Ssid, pAd->PortCfg.SsidLen);
				DBGPRINT(RT_DEBUG_TRACE, "Roaming With NULL SSID after modified the BSSID[#%d]=%s with SSID[%d]=%s", pRoamTab->BssNr,pBss->Bssid,pRoamTab->BssEntry[pRoamTab->BssNr].SsidLen,pRoamTab->BssEntry[pRoamTab->BssNr].Ssid);
			}
		pRoamTab->BssNr += 1;
	}

	if (pRoamTab->BssNr > 0)
	{
		
			pAd->RalinkCounters.PoorCQIRoamingCount ++;
			DBGPRINT(RT_DEBUG_TRACE, "MMCHK - Roaming attempt #%d\n", pAd->RalinkCounters.PoorCQIRoamingCount);
			MlmeEnqueue(pAd, MLME_CNTL_STATE_MACHINE, MT2_MLME_ROAMING_REQ, 0, NULL);
			RTUSBMlmeUp(pAd);	
		
	}
        }
	// Maybe site survey required
	else
	{
		if ((pAd->PortCfg.LastScanTime + 10*HZ) < Now)
		{   
		    
			// check CntlMachine.CurrState to avoid collision with NDIS SetOID request
			DBGPRINT(RT_DEBUG_TRACE, "MMCHK - Roaming, No eligable entry, try a new ACTIVE scan SSID[%s]\n", pAd->MlmeAux.AutoReconnectSsid);
                        pAd->PortCfg.ScanCnt = 2;
			pAd->PortCfg.LastScanTime = Now;
            ScanParmFill(pAd, &ScanReq, pAd->MlmeAux.AutoReconnectSsid, pAd->MlmeAux.AutoReconnectSsidLen, BSS_ANY, SCAN_ACTIVE);
			MlmeEnqueue(pAd, SYNC_STATE_MACHINE, MT2_MLME_SCAN_REQ, 
						sizeof(MLME_SCAN_REQ_STRUCT), &ScanReq);
			RTUSBMlmeUp(pAd);			
			pAd->Mlme.CntlMachine.CurrState = CNTL_WAIT_OID_LIST_SCAN;
		}
	}

	DBGPRINT(RT_DEBUG_TRACE, "<== MlmeCheckForFastRoaming\n");	
}

/*
	==========================================================================
	Description:
		This routine calculates TxPER, RxPER of the past N-sec period. And 
		according to the calculation result, ChannelQuality is calculated here 
		to decide if current AP is still doing the job. 

		If ChannelQuality is not good, a ROAMing attempt may be tried later.
	Output:
		PortCfg.ChannelQuality - 0..100

		
	NOTE: This routine decide channle quality based on RX CRC error ratio.
		Caller should make sure a function call to NICUpdateRawCounters(pAd)
		is performed right before this routine, so that this routine can decide
		channel quality based on the most up-to-date information
	==========================================================================
 */
VOID MlmeCalculateChannelQuality(
	IN PRTMP_ADAPTER pAd,
	IN ULONG Now32)
{
	ULONG TxOkCnt, TxCnt, TxPER, TxPRR;
	ULONG RxCnt, RxPER;
	UCHAR NorRssi;

	//
	// calculate TX packet error ratio and TX retry ratio - if too few TX samples, skip TX related statistics
	//
	TxOkCnt = pAd->RalinkCounters.OneSecTxNoRetryOkCount + pAd->RalinkCounters.OneSecTxRetryOkCount;
	TxCnt = TxOkCnt + pAd->RalinkCounters.OneSecTxFailCount;
	if (TxCnt < 5) 
	{
		TxPER = 0;
		TxPRR = 0;
	}
	else 
	{
		TxPER = (pAd->RalinkCounters.OneSecTxFailCount * 100) / TxCnt; 
		TxPRR = ((TxCnt - pAd->RalinkCounters.OneSecTxNoRetryOkCount) * 100) / TxCnt;
	}

	//
	// calculate RX PER - don't take RxPER into consideration if too few sample
	//
	RxCnt = pAd->RalinkCounters.OneSecRxOkCnt + pAd->RalinkCounters.OneSecRxFcsErrCnt;
	if (RxCnt < 5)
		RxPER = 0;	
	else
		RxPER = (pAd->RalinkCounters.OneSecRxFcsErrCnt * 100) / RxCnt;
	
	//
	// decide ChannelQuality based on: 1)last BEACON received time, 2)last RSSI, 3)TxPER, and 4)RxPER
	//
	if (INFRA_ON(pAd) && 
		(TxOkCnt < 2) && // no heavy traffic
		(pAd->PortCfg.LastBeaconRxTime + BEACON_LOST_TIME < Now32))
	{
		DBGPRINT(RT_DEBUG_TRACE, "BEACON lost > %d msec with TxOkCnt=%d -> CQI=0\n", BEACON_LOST_TIME, TxOkCnt); 
		pAd->Mlme.ChannelQuality = 0;
	}
	else
	{
		// Normalize Rssi
		if (pAd->PortCfg.LastRssi > 0x50)
			NorRssi = 100;
		else if (pAd->PortCfg.LastRssi < 0x20)
			NorRssi = 0;
		else
			NorRssi = (pAd->PortCfg.LastRssi - 0x20) * 2;
		
		// ChannelQuality = W1*RSSI + W2*TxPRR + W3*RxPER	 (RSSI 0..100), (TxPER 100..0), (RxPER 100..0)
		pAd->Mlme.ChannelQuality = (RSSI_WEIGHTING * NorRssi + 
									TX_WEIGHTING * (100 - TxPRR) + 
									RX_WEIGHTING* (100 - RxPER)) / 100;
		if (pAd->Mlme.ChannelQuality >= 100)
			pAd->Mlme.ChannelQuality = 100;
	}
	
	DBGPRINT(RT_DEBUG_INFO, "MMCHK - CQI= %d (Tx Fail=%d/Retry=%d/Total=%d, Rx Fail=%d/Total=%d, RSSI=%d dbm)\n", 
		pAd->Mlme.ChannelQuality, 
		pAd->RalinkCounters.OneSecTxFailCount, 
		pAd->RalinkCounters.OneSecTxRetryOkCount, 
		TxCnt, 
		pAd->RalinkCounters.OneSecRxFcsErrCnt, 
		RxCnt, pAd->PortCfg.LastRssi - pAd->BbpRssiToDbmDelta);

}

/*
	==========================================================================
	Description:
		This routine calculates the acumulated TxPER of eaxh TxRate. And 
		according to the calculation result, change PortCfg.TxRate which 
		is the stable TX Rate we expect the Radio situation could sustained. 

		PortCfg.TxRate will change dynamically within {RATE_1/RATE_6, MaxTxRate} 
	Output:
		PortCfg.TxRate -