libertas: implement new scanning logic

This changes the code that is used for scanning and makes it hopefully
easier to understand:

* move function into logical blocks
* create a bunch of lbs_scan_add_XXXX_tlv() functions, that
  help to create the TLV parameter of CMD_802_11_SCAN
* all of them are now called from the much simpler lbs_do_scan()
* no **puserscancfg double-pointers :-)

Signed-off-by: Holger Schurig <hs4233@mail.mn-solutions.de>
Acked-by: Dan Williams <dcbw@redhat.com>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/libertas/dev.h

@@ -366,9 +366,8 @@ struct lbs_adapter {
 	struct cmd_ds_802_11_get_log logmsg;
 
 	u32 monitormode;
+	int last_scanned_channel;
 	u8 fw_ready;
-
-	u8 last_scanned_channel;
 };
 
 #endif

drivers/net/wireless/libertas/scan.c

@@ -79,6 +79,22 @@ static inline void clear_bss_descriptor (struct bss_descriptor * bss)
 	memset(bss, 0, offsetof(struct bss_descriptor, list));
 }
 
+/**
+ *  @brief Compare two SSIDs
+ *
+ *  @param ssid1    A pointer to ssid to compare
+ *  @param ssid2    A pointer to ssid to compare
+ *
+ *  @return         0: ssid is same, otherwise is different
+ */
+int lbs_ssid_cmp(u8 *ssid1, u8 ssid1_len, u8 *ssid2, u8 ssid2_len)
+{
+	if (ssid1_len != ssid2_len)
+		return -1;
+
+	return memcmp(ssid1, ssid2, ssid1_len);
+}
+
 static inline int match_bss_no_security(struct lbs_802_11_security *secinfo,
 			struct bss_descriptor * match_bss)
 {
@@ -149,6 +165,18 @@ static inline int match_bss_dynamic_wep(struct lbs_802_11_security *secinfo,
 	return 0;
 }
 
+static inline int is_same_network(struct bss_descriptor *src,
+				  struct bss_descriptor *dst)
+{
+	/* A network is only a duplicate if the channel, BSSID, and ESSID
+	 * all match.  We treat all <hidden> with the same BSSID and channel
+	 * as one network */
+	return ((src->ssid_len == dst->ssid_len) &&
+		(src->channel == dst->channel) &&
+		!compare_ether_addr(src->bssid, dst->bssid) &&
+		!memcmp(src->ssid, dst->ssid, src->ssid_len));
+}
+
 /**
  *  @brief Check if a scanned network compatible with the driver settings
  *
@@ -184,9 +212,9 @@ static int is_network_compatible(struct lbs_adapter *adapter,
 		goto done;
 	} else if ((matched = match_bss_wpa(&adapter->secinfo, bss))) {
 		lbs_deb_scan(
-		       "is_network_compatible() WPA: wpa_ie=%#x "
-		       "wpa2_ie=%#x WEP=%s WPA=%s WPA2=%s "
-		       "privacy=%#x\n", bss->wpa_ie[0], bss->rsn_ie[0],
+		       "is_network_compatible() WPA: wpa_ie 0x%x "
+		       "wpa2_ie 0x%x WEP %s WPA %s WPA2 %s "
+		       "privacy 0x%x\n", bss->wpa_ie[0], bss->rsn_ie[0],
 		       adapter->secinfo.wep_enabled ? "e" : "d",
 		       adapter->secinfo.WPAenabled ? "e" : "d",
 		       adapter->secinfo.WPA2enabled ? "e" : "d",
@@ -194,9 +222,9 @@ static int is_network_compatible(struct lbs_adapter *adapter,
 		goto done;
 	} else if ((matched = match_bss_wpa2(&adapter->secinfo, bss))) {
 		lbs_deb_scan(
-		       "is_network_compatible() WPA2: wpa_ie=%#x "
-		       "wpa2_ie=%#x WEP=%s WPA=%s WPA2=%s "
-		       "privacy=%#x\n", bss->wpa_ie[0], bss->rsn_ie[0],
+		       "is_network_compatible() WPA2: wpa_ie 0x%x "
+		       "wpa2_ie 0x%x WEP %s WPA %s WPA2 %s "
+		       "privacy 0x%x\n", bss->wpa_ie[0], bss->rsn_ie[0],
 		       adapter->secinfo.wep_enabled ? "e" : "d",
 		       adapter->secinfo.WPAenabled ? "e" : "d",
 		       adapter->secinfo.WPA2enabled ? "e" : "d",
@@ -205,7 +233,7 @@ static int is_network_compatible(struct lbs_adapter *adapter,
 	} else if ((matched = match_bss_dynamic_wep(&adapter->secinfo, bss))) {
 		lbs_deb_scan(
 		       "is_network_compatible() dynamic WEP: "
-		       "wpa_ie=%#x wpa2_ie=%#x privacy=%#x\n",
+		       "wpa_ie 0x%x wpa2_ie 0x%x privacy 0x%x\n",
 		       bss->wpa_ie[0], bss->rsn_ie[0],
 		       (bss->capability & WLAN_CAPABILITY_PRIVACY));
 		goto done;
@@ -213,8 +241,8 @@ static int is_network_compatible(struct lbs_adapter *adapter,
 
 	/* bss security settings don't match those configured on card */
 	lbs_deb_scan(
-	       "is_network_compatible() FAILED: wpa_ie=%#x "
-	       "wpa2_ie=%#x WEP=%s WPA=%s WPA2=%s privacy=%#x\n",
+	       "is_network_compatible() FAILED: wpa_ie 0x%x "
+	       "wpa2_ie 0x%x WEP %s WPA %s WPA2 %s privacy 0x%x\n",
 	       bss->wpa_ie[0], bss->rsn_ie[0],
 	       adapter->secinfo.wep_enabled ? "e" : "d",
 	       adapter->secinfo.WPAenabled ? "e" : "d",
@@ -226,22 +254,6 @@ done:
 	return matched;
 }
 
-/**
- *  @brief Compare two SSIDs
- *
- *  @param ssid1    A pointer to ssid to compare
- *  @param ssid2    A pointer to ssid to compare
- *
- *  @return         0--ssid is same, otherwise is different
- */
-int lbs_ssid_cmp(u8 *ssid1, u8 ssid1_len, u8 *ssid2, u8 ssid2_len)
-{
-	if (ssid1_len != ssid2_len)
-		return -1;
-
-	return memcmp(ssid1, ssid2, ssid1_len);
-}
-
 
 
 
@@ -251,6 +263,16 @@ int lbs_ssid_cmp(u8 *ssid1, u8 ssid1_len, u8 *ssid2, u8 ssid2_len)
 /*                                                                   */
 /*********************************************************************/
 
+void lbs_scan_worker(struct work_struct *work)
+{
+	struct lbs_private *priv =
+		container_of(work, struct lbs_private, scan_work.work);
+
+	lbs_deb_enter(LBS_DEB_SCAN);
+	lbs_scan_networks(priv, NULL, 0);
+	lbs_deb_leave(LBS_DEB_SCAN);
+}
+
 
 /**
  *  @brief Create a channel list for the driver to scan based on region info
@@ -271,7 +293,7 @@ int lbs_ssid_cmp(u8 *ssid1, u8 ssid1_len, u8 *ssid2, u8 ssid2_len)
  *
  *  @return              void
  */
-static void lbs_scan_create_channel_list(struct lbs_private *priv,
+static int lbs_scan_create_channel_list(struct lbs_private *priv,
 					  struct chanscanparamset * scanchanlist,
 					  u8 filteredscan)
 {
@@ -284,8 +306,6 @@ static void lbs_scan_create_channel_list(struct lbs_private *priv,
 	int nextchan;
 	u8 scantype;
 
-	lbs_deb_enter_args(LBS_DEB_SCAN, "filteredscan %d", filteredscan);
-
 	chanidx = 0;
 
 	/* Set the default scan type to the user specified type, will later
@@ -353,383 +373,151 @@ static void lbs_scan_create_channel_list(struct lbs_private *priv,
 			}
 		}
 	}
+	return chanidx;
 }
 
 
-/* Delayed partial scan worker */
-void lbs_scan_worker(struct work_struct *work)
+/*
+ * Add SSID TLV of the form:
+ *
+ * TLV-ID SSID     00 00
+ * length          06 00
+ * ssid            4d 4e 54 45 53 54
+ */
+static int lbs_scan_add_ssid_tlv(u8 *tlv,
+	const struct lbs_ioctl_user_scan_cfg *user_cfg)
 {
-	struct lbs_private *priv = container_of(work,
-		struct lbs_private,
-		scan_work.work);
-
-	lbs_scan_networks(priv, NULL, 0);
+	struct mrvlietypes_ssidparamset *ssid_tlv =
+		(struct mrvlietypes_ssidparamset *)tlv;
+	ssid_tlv->header.type = cpu_to_le16(TLV_TYPE_SSID);
+	ssid_tlv->header.len = cpu_to_le16(user_cfg->ssid_len);
+	memcpy(ssid_tlv->ssid, user_cfg->ssid, user_cfg->ssid_len);
+	return sizeof(ssid_tlv->header) + user_cfg->ssid_len;
 }
 
 
-/**
- *  @brief Construct a lbs_scan_cmd_config structure to use in issue scan cmds
- *
- *  Application layer or other functions can invoke lbs_scan_networks
- *    with a scan configuration supplied in a lbs_ioctl_user_scan_cfg struct.
- *    This structure is used as the basis of one or many lbs_scan_cmd_config
- *    commands that are sent to the command processing module and sent to
- *    firmware.
- *
- *  Create a lbs_scan_cmd_config based on the following user supplied
- *    parameters (if present):
- *             - SSID filter
- *             - BSSID filter
- *             - Number of Probes to be sent
- *             - channel list
- *
- *  If the SSID or BSSID filter is not present, disable/clear the filter.
- *  Qualify the channel
+/*
+ * Add CHANLIST TLV of the form
  *
- *  @param priv             A pointer to struct lbs_private structure
- *  @param puserscanin      NULL or pointer to scan configuration parameters
- *  @param ppchantlvout     Output parameter: Pointer to the start of the
- *                          channel TLV portion of the output scan config
- *  @param pscanchanlist    Output parameter: Pointer to the resulting channel
- *                          list to scan
- *  @param pmaxchanperscan  Output parameter: Number of channels to scan for
- *                          each issuance of the firmware scan command
- *  @param pfilteredscan    Output parameter: Flag indicating whether or not
- *                          a BSSID or SSID filter is being sent in the
- *                          command to firmware.  Used to increase the number
- *                          of channels sent in a scan command and to
- *                          disable the firmware channel scan filter.
- *  @param pscancurrentonly Output parameter: Flag indicating whether or not
- *                          we are only scanning our current active channel
+ * TLV-ID CHANLIST 01 01
+ * length          5b 00
+ * channel 1       00 01 00 00 00 64 00
+ *   radio type    00
+ *   channel          01
+ *   scan type           00
+ *   min scan time          00 00
+ *   max scan time                64 00
+ * channel 2       00 02 00 00 00 64 00
+ * channel 3       00 03 00 00 00 64 00
+ * channel 4       00 04 00 00 00 64 00
+ * channel 5       00 05 00 00 00 64 00
+ * channel 6       00 06 00 00 00 64 00
+ * channel 7       00 07 00 00 00 64 00
+ * channel 8       00 08 00 00 00 64 00
+ * channel 9       00 09 00 00 00 64 00
+ * channel 10      00 0a 00 00 00 64 00
+ * channel 11      00 0b 00 00 00 64 00
+ * channel 12      00 0c 00 00 00 64 00
+ * channel 13      00 0d 00 00 00 64 00
  *
- *  @return                 resulting scan configuration
  */
-static struct lbs_scan_cmd_config *
-lbs_scan_setup_scan_config(struct lbs_private *priv,
-			    const struct lbs_ioctl_user_scan_cfg *puserscanin,
-			    struct mrvlietypes_chanlistparamset ** ppchantlvout,
-			    struct chanscanparamset * pscanchanlist,
-			    int *pmaxchanperscan,
-			    u8 * pfilteredscan,
-			    u8 * pscancurrentonly)
+static int lbs_scan_add_chanlist_tlv(u8 *tlv,
+	struct chanscanparamset *chan_list,
+	int chan_count)
 {
-	struct mrvlietypes_ssidparamset *pssidtlv;
-	struct lbs_scan_cmd_config *pscancfgout = NULL;
-	u8 *ptlvpos;
-
-	lbs_deb_enter(LBS_DEB_SCAN);
-
-	pscancfgout = kzalloc(MAX_SCAN_CFG_ALLOC, GFP_KERNEL);
-	if (pscancfgout == NULL)
-		goto out;
-
-	/* The tlvbufferlen is calculated for each scan command.  The TLVs added
-	 *   in this routine will be preserved since the routine that sends
-	 *   the command will append channelTLVs at *ppchantlvout.  The difference
-	 *   between the *ppchantlvout and the tlvbuffer start will be used
-	 *   to calculate the size of anything we add in this routine.
-	 */
-	pscancfgout->tlvbufferlen = 0;
-
-	/* Running tlv pointer.  Assigned to ppchantlvout at end of function
-	 *  so later routines know where channels can be added to the command buf
-	 */
-	ptlvpos = pscancfgout->tlvbuffer;
-
-	/*
-	 * Set the initial scan paramters for progressive scanning.  If a specific
-	 *   BSSID or SSID is used, the number of channels in the scan command
-	 *   will be increased to the absolute maximum
-	 */
-	*pmaxchanperscan = MRVDRV_CHANNELS_PER_SCAN_CMD;
-
-	/* Initialize the scan as un-filtered by firmware, set to TRUE below if
-	 *   a SSID or BSSID filter is sent in the command
-	 */
-	*pfilteredscan = 0;
-
-	/* Initialize the scan as not being only on the current channel.  If
-	 *   the channel list is customized, only contains one channel, and
-	 *   is the active channel, this is set true and data flow is not halted.
-	 */
-	*pscancurrentonly = 0;
-
-	if (puserscanin) {
-		/* Set the bss type scan filter, use adapter setting if unset */
-		pscancfgout->bsstype =
-		    puserscanin->bsstype ? puserscanin->bsstype : CMD_BSS_TYPE_ANY;
-
-		/*
-		 * Set the BSSID filter to the incoming configuration,
-		 *   if non-zero.  If not set, it will remain disabled (all zeros).
-		 */
-		memcpy(pscancfgout->bssid, puserscanin->bssid,
-		       sizeof(pscancfgout->bssid));
-
-		if (puserscanin->ssid_len) {
-			pssidtlv =
-			    (struct mrvlietypes_ssidparamset *) pscancfgout->
-			    tlvbuffer;
-			pssidtlv->header.type = cpu_to_le16(TLV_TYPE_SSID);
-			pssidtlv->header.len = cpu_to_le16(puserscanin->ssid_len);
-			memcpy(pssidtlv->ssid, puserscanin->ssid,
-			       puserscanin->ssid_len);
-			ptlvpos += sizeof(pssidtlv->header) + puserscanin->ssid_len;
-		}
-
-		/*
-		 *  The default number of channels sent in the command is low to
-		 *    ensure the response buffer from the firmware does not truncate
-		 *    scan results.  That is not an issue with an SSID or BSSID
-		 *    filter applied to the scan results in the firmware.
-		 */
-		if (   puserscanin->ssid_len
-		    || (compare_ether_addr(pscancfgout->bssid, &zeromac[0]) != 0)) {
-			*pmaxchanperscan = MRVDRV_MAX_CHANNELS_PER_SCAN;
-			*pfilteredscan = 1;
-		}
-	} else {
-		pscancfgout->bsstype = CMD_BSS_TYPE_ANY;
-	}
-
-	/*
-	 * Set the output for the channel TLV to the address in the tlv buffer
-	 *   past any TLVs that were added in this fuction (SSID).
-	 *   channel TLVs will be added past this for each scan command, preserving
-	 *   the TLVs that were previously added.
-	 */
-	*ppchantlvout = (struct mrvlietypes_chanlistparamset *) ptlvpos;
-
-	lbs_scan_create_channel_list(priv, pscanchanlist,
-				      *pfilteredscan);
-out:
-	return pscancfgout;
+	size_t size = sizeof(struct chanscanparamset) * chan_count;
+	struct mrvlietypes_chanlistparamset *chan_tlv =
+		(struct mrvlietypes_chanlistparamset *) tlv;
+
+	chan_tlv->header.type = cpu_to_le16(TLV_TYPE_CHANLIST);
+	memcpy(chan_tlv->chanscanparam, chan_list, size);
+	chan_tlv->header.len = cpu_to_le16(size);
+	return sizeof(chan_tlv->header) + size;
 }
 
-/**
- *  @brief Construct and send multiple scan config commands to the firmware
- *
- *  Only used from lbs_scan_networks()
- *
- *  Previous routines have created a lbs_scan_cmd_config with any requested
- *   TLVs.  This function splits the channel TLV into maxchanperscan lists
- *   and sends the portion of the channel TLV along with the other TLVs
- *   to the lbs_cmd routines for execution in the firmware.
+
+/*
+ * Add RATES TLV of the form
  *
- *  @param priv            A pointer to struct lbs_private structure
- *  @param maxchanperscan  Maximum number channels to be included in each
- *                         scan command sent to firmware
- *  @param filteredscan    Flag indicating whether or not a BSSID or SSID
- *                         filter is being used for the firmware command
- *                         scan command sent to firmware
- *  @param pscancfgout     Scan configuration used for this scan.
- *  @param pchantlvout     Pointer in the pscancfgout where the channel TLV
- *                         should start.  This is past any other TLVs that
- *                         must be sent down in each firmware command.
- *  @param pscanchanlist   List of channels to scan in maxchanperscan segments
+ * TLV-ID RATES    01 00
+ * length          0e 00
+ * rates           82 84 8b 96 0c 12 18 24 30 48 60 6c
  *
- *  @return                0 or error return otherwise
+ * The rates are in lbs_bg_rates[], but for the 802.11b
+ * rates the high bit isn't set.
  */
-static int lbs_scan_channel_list(struct lbs_private *priv,
-				  int maxchanperscan,
-				  u8 filteredscan,
-				  struct lbs_scan_cmd_config *pscancfgout,
-				  struct mrvlietypes_chanlistparamset * pchantlvout,
-				  struct chanscanparamset * pscanchanlist,
-				  const struct lbs_ioctl_user_scan_cfg *puserscanin,
-				  int full_scan)
+static int lbs_scan_add_rates_tlv(u8 *tlv)
 {
-	struct chanscanparamset *ptmpchan;
-	struct chanscanparamset *pstartchan;
-	u8 scanband;
-	int doneearly;
-	int tlvidx;
-	int ret = 0;
-	int scanned = 0;
-	union iwreq_data wrqu;
-
-	lbs_deb_enter_args(LBS_DEB_SCAN, "maxchanperscan %d, filteredscan %d, "
-		"full_scan %d", maxchanperscan, filteredscan, full_scan);
-
-	if (!pscancfgout || !pchantlvout || !pscanchanlist) {
-		lbs_deb_scan("pscancfgout, pchantlvout or "
-			"pscanchanlist is NULL\n");
-		ret = -1;
-		goto out;
-	}
-
-	pchantlvout->header.type = cpu_to_le16(TLV_TYPE_CHANLIST);
-
-	/* Set the temp channel struct pointer to the start of the desired list */
-	ptmpchan = pscanchanlist;
-
-	if (priv->adapter->last_scanned_channel && !puserscanin)
-		ptmpchan += priv->adapter->last_scanned_channel;
-
-	/* Loop through the desired channel list, sending a new firmware scan
-	 *   commands for each maxchanperscan channels (or for 1,6,11 individually
-	 *   if configured accordingly)
-	 */
-	while (ptmpchan->channumber) {
-
-		tlvidx = 0;
-		pchantlvout->header.len = 0;
-		scanband = ptmpchan->radiotype;
-		pstartchan = ptmpchan;
-		doneearly = 0;
-
-		/* Construct the channel TLV for the scan command.  Continue to
-		 *  insert channel TLVs until:
-		 *    - the tlvidx hits the maximum configured per scan command
-		 *    - the next channel to insert is 0 (end of desired channel list)
-		 *    - doneearly is set (controlling individual scanning of 1,6,11)
-		 */
-		while (tlvidx < maxchanperscan && ptmpchan->channumber
-		       && !doneearly && scanned < 2) {
-
-			lbs_deb_scan("channel %d, radio %d, passive %d, "
-				"dischanflt %d, maxscantime %d\n",
-				ptmpchan->channumber,
-				ptmpchan->radiotype,
-			             ptmpchan->chanscanmode.passivescan,
-			             ptmpchan->chanscanmode.disablechanfilt,
-			             ptmpchan->maxscantime);
-
-			/* Copy the current channel TLV to the command being prepared */
-			memcpy(pchantlvout->chanscanparam + tlvidx,
-			       ptmpchan, sizeof(pchantlvout->chanscanparam));
-
-			/* Increment the TLV header length by the size appended */
-			/* Ew, it would be _so_ nice if we could just declare the
-			   variable little-endian and let GCC handle it for us */
-			pchantlvout->header.len =
-				cpu_to_le16(le16_to_cpu(pchantlvout->header.len) +
-					    sizeof(pchantlvout->chanscanparam));
-
-			/*
-			 *  The tlv buffer length is set to the number of bytes of the
-			 *    between the channel tlv pointer and the start of the
-			 *    tlv buffer.  This compensates for any TLVs that were appended
-			 *    before the channel list.
-			 */
-			pscancfgout->tlvbufferlen = ((u8 *) pchantlvout
-						     - pscancfgout->tlvbuffer);
-
-			/*  Add the size of the channel tlv header and the data length */
-			pscancfgout->tlvbufferlen +=
-			    (sizeof(pchantlvout->header)
-			     + le16_to_cpu(pchantlvout->header.len));
-
-			/* Increment the index to the channel tlv we are constructing */
-			tlvidx++;
-
-			doneearly = 0;
-
-			/* Stop the loop if the *current* channel is in the 1,6,11 set
-			 *   and we are not filtering on a BSSID or SSID.
-			 */
-			if (!filteredscan && (ptmpchan->channumber == 1
-					      || ptmpchan->channumber == 6
-					      || ptmpchan->channumber == 11)) {
-				doneearly = 1;
-			}
-
-			/* Increment the tmp pointer to the next channel to be scanned */
-			ptmpchan++;
-			scanned++;
-
-			/* Stop the loop if the *next* channel is in the 1,6,11 set.
-			 *  This will cause it to be the only channel scanned on the next
-			 *  interation
-			 */
-			if (!filteredscan && (ptmpchan->channumber == 1
-					      || ptmpchan->channumber == 6
-					      || ptmpchan->channumber == 11)) {
-				doneearly = 1;
-			}
-		}
-
-		/* Send the scan command to the firmware with the specified cfg */
-		ret = lbs_prepare_and_send_command(priv, CMD_802_11_SCAN, 0,
-					    0, 0, pscancfgout);
-		if (scanned >= 2 && !full_scan) {
-			ret = 0;
-			goto done;
-		}
-		scanned = 0;
-	}
-
-done:
-	priv->adapter->last_scanned_channel = ptmpchan->channumber;
-
-	if (priv->adapter->last_scanned_channel) {
-		/* Schedule the next part of the partial scan */
-		if (!full_scan && !priv->adapter->surpriseremoved) {
-			cancel_delayed_work(&priv->scan_work);
-			queue_delayed_work(priv->work_thread, &priv->scan_work,
-			                   msecs_to_jiffies(300));
-		}
-	} else {
-		/* All done, tell userspace the scan table has been updated */
-		memset(&wrqu, 0, sizeof(union iwreq_data));
-		wireless_send_event(priv->dev, SIOCGIWSCAN, &wrqu, NULL);
+	int i;
+	struct mrvlietypes_ratesparamset *rate_tlv =
+		(struct mrvlietypes_ratesparamset *) tlv;
+
+	rate_tlv->header.type = cpu_to_le16(TLV_TYPE_RATES);
+	tlv += sizeof(rate_tlv->header);
+	for (i = 0; i < MAX_RATES; i++) {
+		*tlv = lbs_bg_rates[i];
+		if (*tlv == 0)
+			break;
+		/* This code makes sure that the 802.11b rates (1 MBit/s, 2
+		   MBit/s, 5.5 MBit/s and 11 MBit/s get's the high bit set.
+		   Note that the values are MBit/s * 2, to mark them as
+		   basic rates so that the firmware likes it better */
+		if (*tlv == 0x02 || *tlv == 0x04 ||
+		    *tlv == 0x0b || *tlv == 0x16)
+			*tlv |= 0x80;
+		tlv++;
 	}
-
-out:
-	lbs_deb_leave_args(LBS_DEB_SCAN, "ret %d", ret);
-	return ret;
+	rate_tlv->header.len = cpu_to_le16(i);
+	return sizeof(rate_tlv->header) + i;
 }
 
+
 /*
- * Only used from lbs_scan_networks()
-*/
-static void clear_selected_scan_list_entries(struct lbs_adapter *adapter,
-	const struct lbs_ioctl_user_scan_cfg *scan_cfg)
+ * Generate the CMD_802_11_SCAN command with the proper tlv
+ * for a bunch of channels.
+ */
+static int lbs_do_scan(struct lbs_private *priv,
+	u8 bsstype,
+	struct chanscanparamset *chan_list,
+	int chan_count,
+	const struct lbs_ioctl_user_scan_cfg *user_cfg)
 {
-	struct bss_descriptor *bss;
-	struct bss_descriptor *safe;
-	u32 clear_ssid_flag = 0, clear_bssid_flag = 0;
+	int ret = -ENOMEM;
+	struct lbs_scan_cmd_config *scan_cmd;
+	u8 *tlv;    /* pointer into our current, growing TLV storage area */
 
-	lbs_deb_enter(LBS_DEB_SCAN);
+	lbs_deb_enter_args(LBS_DEB_SCAN, "bsstype %d, chanlist[].chan %d, "
+		"chan_count %d",
+		bsstype, chan_list[0].channumber, chan_count);
 
-	if (!scan_cfg)
+	/* create the fixed part for scan command */
+	scan_cmd = kzalloc(MAX_SCAN_CFG_ALLOC, GFP_KERNEL);
+	if (scan_cmd == NULL)
 		goto out;
-
-	if (scan_cfg->clear_ssid && scan_cfg->ssid_len)
-		clear_ssid_flag = 1;
-
-	if (scan_cfg->clear_bssid
-	    && (compare_ether_addr(scan_cfg->bssid, &zeromac[0]) != 0)
-	    && (compare_ether_addr(scan_cfg->bssid, &bcastmac[0]) != 0)) {
-		clear_bssid_flag = 1;
-	}
-
-	if (!clear_ssid_flag && !clear_bssid_flag)
-		goto out;
-
-	mutex_lock(&adapter->lock);
-	list_for_each_entry_safe (bss, safe, &adapter->network_list, list) {
-		u32 clear = 0;
-
-		/* Check for an SSID match */
-		if (   clear_ssid_flag
-		    && (bss->ssid_len == scan_cfg->ssid_len)
-		    && !memcmp(bss->ssid, scan_cfg->ssid, bss->ssid_len))
-			clear = 1;
-
-		/* Check for a BSSID match */
-		if (   clear_bssid_flag
-		    && !compare_ether_addr(bss->bssid, scan_cfg->bssid))
-			clear = 1;
-
-		if (clear) {
-			list_move_tail (&bss->list, &adapter->network_free_list);
-			clear_bss_descriptor(bss);
-		}
-	}
-	mutex_unlock(&adapter->lock);
+	tlv = scan_cmd->tlvbuffer;
+	if (user_cfg)
+		memcpy(scan_cmd->bssid, user_cfg->bssid, ETH_ALEN);
+	scan_cmd->bsstype = bsstype;
+
+	/* add TLVs */
+	if (user_cfg && user_cfg->ssid_len)
+		tlv += lbs_scan_add_ssid_tlv(tlv, user_cfg);
+	if (chan_list && chan_count)
+		tlv += lbs_scan_add_chanlist_tlv(tlv, chan_list, chan_count);
+	tlv += lbs_scan_add_rates_tlv(tlv);
+
+	/* This is the final data we are about to send */
+	scan_cmd->tlvbufferlen = tlv - scan_cmd->tlvbuffer;
+	lbs_deb_hex(LBS_DEB_SCAN, "SCAN_CMD", (void *)scan_cmd, 1+6);
+	lbs_deb_hex(LBS_DEB_SCAN, "SCAN_TLV", scan_cmd->tlvbuffer,
+		scan_cmd->tlvbufferlen);
+
+	ret = lbs_prepare_and_send_command(priv, CMD_802_11_SCAN, 0,
+		CMD_OPTION_WAITFORRSP, 0, scan_cmd);
 out:
-	lbs_deb_leave(LBS_DEB_SCAN);
+	kfree(scan_cmd);
+	lbs_deb_leave_args(LBS_DEB_SCAN, "ret %d", ret);
+	return ret;
 }
 
 
@@ -745,29 +533,30 @@ out:
  *  @param priv          A pointer to struct lbs_private structure
  *  @param puserscanin   Pointer to the input configuration for the requested
  *                       scan.
- *  @param full_scan     ???
  *
  *  @return              0 or < 0 if error
  */
 int lbs_scan_networks(struct lbs_private *priv,
-	const struct lbs_ioctl_user_scan_cfg *puserscanin,
+	const struct lbs_ioctl_user_scan_cfg *user_cfg,
                        int full_scan)
 {
 	struct lbs_adapter *adapter = priv->adapter;
-	struct mrvlietypes_chanlistparamset *pchantlvout;
-	struct chanscanparamset * scan_chan_list = NULL;
-	struct lbs_scan_cmd_config *scan_cfg = NULL;
-	u8 filteredscan;
-	u8 scancurrentchanonly;
-	int maxchanperscan;
-	int ret;
+	int ret = -ENOMEM;
+	struct chanscanparamset *chan_list;
+	struct chanscanparamset *curr_chans;
+	int chan_count;
+	u8 bsstype = CMD_BSS_TYPE_ANY;
+	int numchannels = MRVDRV_CHANNELS_PER_SCAN_CMD;
+	int filteredscan = 0;
+	union iwreq_data wrqu;
 #ifdef CONFIG_LIBERTAS_DEBUG
-	struct bss_descriptor * iter_bss;
+	struct bss_descriptor *iter;
 	int i = 0;
 	DECLARE_MAC_BUF(mac);
 #endif
 
-	lbs_deb_enter_args(LBS_DEB_SCAN, "full_scan %d", full_scan);
+	lbs_deb_enter_args(LBS_DEB_SCAN, "full_scan %d",
+		full_scan);
 
 	/* Cancel any partial outstanding partial scans if this scan
 	 * is a full scan.
@@ -775,85 +564,130 @@ int lbs_scan_networks(struct lbs_private *priv,
 	if (full_scan && delayed_work_pending(&priv->scan_work))
 		cancel_delayed_work(&priv->scan_work);
 
-	scan_chan_list = kzalloc(sizeof(struct chanscanparamset) *
-				LBS_IOCTL_USER_SCAN_CHAN_MAX, GFP_KERNEL);
-	if (scan_chan_list == NULL) {
-		ret = -ENOMEM;
-		goto out;
+	/* Determine same scan parameters */
+	if (user_cfg) {
+		if (user_cfg->bsstype)
+			bsstype = user_cfg->bsstype;
+		if (compare_ether_addr(user_cfg->bssid, &zeromac[0]) != 0) {
+			numchannels = MRVDRV_MAX_CHANNELS_PER_SCAN;
+			filteredscan = 1;
+		}
 	}
+	lbs_deb_scan("numchannels %d, bsstype %d, "
+		"filteredscan %d\n",
+		numchannels, bsstype, filteredscan);
 
-	scan_cfg = lbs_scan_setup_scan_config(priv,
-					       puserscanin,
-					       &pchantlvout,
-					       scan_chan_list,
-					       &maxchanperscan,
-					       &filteredscan,
-					       &scancurrentchanonly);
-	if (scan_cfg == NULL) {
-		ret = -ENOMEM;
+	/* Create list of channels to scan */
+	chan_list = kzalloc(sizeof(struct chanscanparamset) *
+				LBS_IOCTL_USER_SCAN_CHAN_MAX, GFP_KERNEL);
+	if (!chan_list) {
+		lbs_pr_alert("SCAN: chan_list empty\n");
 		goto out;
 	}
 
-	clear_selected_scan_list_entries(adapter, puserscanin);
+	/* We want to scan all channels */
+	chan_count = lbs_scan_create_channel_list(priv, chan_list,
+		filteredscan);
 
-	/* Keep the data path active if we are only scanning our current channel */
-	if (!scancurrentchanonly) {
-		netif_stop_queue(priv->dev);
-		netif_carrier_off(priv->dev);
-		if (priv->mesh_dev) {
+	netif_stop_queue(priv->dev);
+	netif_carrier_off(priv->dev);
+	if (priv->mesh_dev) {
 			netif_stop_queue(priv->mesh_dev);
 			netif_carrier_off(priv->mesh_dev);
-		}
 	}
 
-	ret = lbs_scan_channel_list(priv,
-				     maxchanperscan,
-				     filteredscan,
-				     scan_cfg,
-				     pchantlvout,
-				     scan_chan_list,
-				     puserscanin,
-				     full_scan);
+	/* Prepare to continue an interrupted scan */
+	lbs_deb_scan("chan_count %d, last_scanned_channel %d\n",
+		chan_count, adapter->last_scanned_channel);
+	curr_chans = chan_list;
+	/* advance channel list by already-scanned-channels */
+	if (adapter->last_scanned_channel > 0) {
+		curr_chans += adapter->last_scanned_channel;
+		chan_count -= adapter->last_scanned_channel;
+	}
+
+	/* Send scan command(s)
+	 * numchannels contains the number of channels we should maximally scan
+	 * chan_count is the total number of channels to scan
+	 */
+
+	while (chan_count) {
+		int to_scan = min(numchannels, chan_count);
+		lbs_deb_scan("scanning %d of %d channels\n",
+			to_scan, chan_count);
+		ret = lbs_do_scan(priv, bsstype, curr_chans,
+			to_scan, user_cfg);
+		if (ret) {
+			lbs_pr_err("SCAN_CMD failed\n");
+			goto out2;
+		}
+		curr_chans += to_scan;
+		chan_count -= to_scan;
+
+		/* somehow schedule the next part of the scan */
+		if (chan_count &&
+		    !full_scan &&
+		    !priv->adapter->surpriseremoved) {
+			/* -1 marks just that we're currently scanning */
+			if (adapter->last_scanned_channel < 0)
+				adapter->last_scanned_channel = to_scan;
+			else
+				adapter->last_scanned_channel += to_scan;
+			cancel_delayed_work(&priv->scan_work);
+			queue_delayed_work(priv->work_thread, &priv->scan_work,
+				msecs_to_jiffies(300));
+			/* skip over GIWSCAN event */
+			goto out;
+		}
+
+	}
+	memset(&wrqu, 0, sizeof(union iwreq_data));
+	wireless_send_event(priv->dev, SIOCGIWSCAN, &wrqu, NULL);
 
 #ifdef CONFIG_LIBERTAS_DEBUG
 	/* Dump the scan table */
 	mutex_lock(&adapter->lock);
-	lbs_deb_scan("The scan table contains:\n");
-	list_for_each_entry (iter_bss, &adapter->network_list, list) {
-		lbs_deb_scan("scan %02d, %s, RSSI, %d, SSID '%s'\n",
-		       i++, print_mac(mac, iter_bss->bssid), (s32) iter_bss->rssi,
-		       escape_essid(iter_bss->ssid, iter_bss->ssid_len));
-	}
+	lbs_deb_scan("scan table:\n");
+	list_for_each_entry(iter, &adapter->network_list, list)
+		lbs_deb_scan("%02d: BSSID %s, RSSI %d, SSID '%s'\n",
+		       i++, print_mac(mac, iter->bssid), (s32) iter->rssi,
+		       escape_essid(iter->ssid, iter->ssid_len));
 	mutex_unlock(&adapter->lock);
 #endif
 
+out2:
+	adapter->last_scanned_channel = 0;
+
+out:
 	if (adapter->connect_status == LBS_CONNECTED) {
 		netif_carrier_on(priv->dev);
 		netif_wake_queue(priv->dev);
 	}
-
 	if (priv->mesh_dev && (adapter->mesh_connect_status == LBS_CONNECTED)) {
 		netif_carrier_on(priv->mesh_dev);
 		netif_wake_queue(priv->mesh_dev);
 	}
-
-out:
-	if (scan_cfg)
-		kfree(scan_cfg);
-
-	if (scan_chan_list)
-		kfree(scan_chan_list);
+	kfree(chan_list);
 
 	lbs_deb_leave_args(LBS_DEB_SCAN, "ret %d", ret);
 	return ret;
 }
 
+
+
+
+/*********************************************************************/
+/*                                                                   */
+/*  Result interpretation                                            */
+/*                                                                   */
+/*********************************************************************/
+
 /**
  *  @brief Interpret a BSS scan response returned from the firmware
  *
  *  Parse the various fixed fields and IEs passed back for a a BSS probe
- *   response or beacon from the scan command.  Record information as needed
- *   in the scan table struct bss_descriptor for that entry.
+ *  response or beacon from the scan command.  Record information as needed
+ *  in the scan table struct bss_descriptor for that entry.
  *
  *  @param bss  Output parameter: Pointer to the BSS Entry
  *
@@ -898,7 +732,7 @@ static int lbs_process_bss(struct bss_descriptor *bss,
 	*bytesleft -= beaconsize;
 
 	memcpy(bss->bssid, pos, ETH_ALEN);
-	lbs_deb_scan("process_bss: AP BSSID %s\n", print_mac(mac, bss->bssid));
+	lbs_deb_scan("process_bss: BSSID %s\n", print_mac(mac, bss->bssid));
 	pos += ETH_ALEN;
 
 	if ((end - pos) < 12) {
@@ -914,7 +748,7 @@ static int lbs_process_bss(struct bss_descriptor *bss,
 
 	/* RSSI is 1 byte long */
 	bss->rssi = *pos;
-	lbs_deb_scan("process_bss: RSSI=%02X\n", *pos);
+	lbs_deb_scan("process_bss: RSSI %d\n", *pos);
 	pos++;
 
 	/* time stamp is 8 bytes long */
@@ -926,18 +760,18 @@ static int lbs_process_bss(struct bss_descriptor *bss,
 
 	/* capability information is 2 bytes long */
 	bss->capability = le16_to_cpup((void *) pos);
-	lbs_deb_scan("process_bss: capabilities = 0x%4X\n", bss->capability);
+	lbs_deb_scan("process_bss: capabilities 0x%04x\n", bss->capability);
 	pos += 2;
 
 	if (bss->capability & WLAN_CAPABILITY_PRIVACY)
-		lbs_deb_scan("process_bss: AP WEP enabled\n");
+		lbs_deb_scan("process_bss: WEP enabled\n");
 	if (bss->capability & WLAN_CAPABILITY_IBSS)
 		bss->mode = IW_MODE_ADHOC;
 	else
 		bss->mode = IW_MODE_INFRA;
 
 	/* rest of the current buffer are IE's */
-	lbs_deb_scan("process_bss: IE length for this AP = %zd\n", end - pos);
+	lbs_deb_scan("process_bss: IE len %zd\n", end - pos);
 	lbs_deb_hex(LBS_DEB_SCAN, "process_bss: IE info", pos, end - pos);
 
 	/* process variable IE */
@@ -955,7 +789,7 @@ static int lbs_process_bss(struct bss_descriptor *bss,
 		case MFIE_TYPE_SSID:
 			bss->ssid_len = elem->len;
 			memcpy(bss->ssid, elem->data, elem->len);
-			lbs_deb_scan("ssid '%s', ssid length %u\n",
+			lbs_deb_scan("got SSID IE: '%s', len %u\n",
 			             escape_essid(bss->ssid, bss->ssid_len),
 			             bss->ssid_len);
 			break;
@@ -964,16 +798,14 @@ static int lbs_process_bss(struct bss_descriptor *bss,
 			n_basic_rates = min_t(u8, MAX_RATES, elem->len);
 			memcpy(bss->rates, elem->data, n_basic_rates);
 			got_basic_rates = 1;
+			lbs_deb_scan("got RATES IE\n");
 			break;
 
 		case MFIE_TYPE_FH_SET:
 			pFH = (struct ieeetypes_fhparamset *) pos;
 			memmove(&bss->phyparamset.fhparamset, pFH,
 				sizeof(struct ieeetypes_fhparamset));
-#if 0 /* I think we can store these LE */
-			bss->phyparamset.fhparamset.dwelltime
-			    = le16_to_cpu(bss->phyparamset.fhparamset.dwelltime);
-#endif
+			lbs_deb_scan("got FH IE\n");
 			break;
 
 		case MFIE_TYPE_DS_SET:
@@ -981,12 +813,14 @@ static int lbs_process_bss(struct bss_descriptor *bss,
 			bss->channel = pDS->currentchan;
 			memcpy(&bss->phyparamset.dsparamset, pDS,
 			       sizeof(struct ieeetypes_dsparamset));
+			lbs_deb_scan("got DS IE, channel %d\n", bss->channel);
 			break;
 
 		case MFIE_TYPE_CF_SET:
 			pCF = (struct ieeetypes_cfparamset *) pos;
 			memcpy(&bss->ssparamset.cfparamset, pCF,
 			       sizeof(struct ieeetypes_cfparamset));
+			lbs_deb_scan("got CF IE\n");
 			break;
 
 		case MFIE_TYPE_IBSS_SET:
@@ -994,18 +828,16 @@ static int lbs_process_bss(struct bss_descriptor *bss,
 			bss->atimwindow = le32_to_cpu(pibss->atimwindow);
 			memmove(&bss->ssparamset.ibssparamset, pibss,
 				sizeof(struct ieeetypes_ibssparamset));
-#if 0
-			bss->ssparamset.ibssparamset.atimwindow
-			    = le16_to_cpu(bss->ssparamset.ibssparamset.atimwindow);
-#endif
+			lbs_deb_scan("got IBSS IE\n");
 			break;
 
 		case MFIE_TYPE_COUNTRY:
 			pcountryinfo = (struct ieeetypes_countryinfoset *) pos;
+			lbs_deb_scan("got COUNTRY IE\n");
 			if (pcountryinfo->len < sizeof(pcountryinfo->countrycode)
 			    || pcountryinfo->len > 254) {
 				lbs_deb_scan("process_bss: 11D- Err "
-				       "CountryInfo len =%d min=%zd max=254\n",
+				       "CountryInfo len %d, min %zd, max 254\n",
 				       pcountryinfo->len,
 				       sizeof(pcountryinfo->countrycode));
 				ret = -1;
@@ -1024,8 +856,11 @@ static int lbs_process_bss(struct bss_descriptor *bss,
 			 * already found. Data rate IE should come before
 			 * extended supported rate IE
 			 */
-			if (!got_basic_rates)
+			lbs_deb_scan("got RATESEX IE\n");
+			if (!got_basic_rates) {
+				lbs_deb_scan("... but ignoring it\n");
 				break;
+			}
 
 			n_ex_rates = elem->len;
 			if (n_basic_rates + n_ex_rates > MAX_RATES)
@@ -1044,24 +879,36 @@ static int lbs_process_bss(struct bss_descriptor *bss,
 				bss->wpa_ie_len = min(elem->len + 2,
 				                      MAX_WPA_IE_LEN);
 				memcpy(bss->wpa_ie, elem, bss->wpa_ie_len);
-				lbs_deb_hex(LBS_DEB_SCAN, "process_bss: WPA IE", bss->wpa_ie,
+				lbs_deb_scan("got WPA IE\n");
+				lbs_deb_hex(LBS_DEB_SCAN, "WPA IE", bss->wpa_ie,
 				            elem->len);
 			} else if (elem->len >= MARVELL_MESH_IE_LENGTH &&
 			    elem->data[0] == 0x00 &&
 			    elem->data[1] == 0x50 &&
 			    elem->data[2] == 0x43 &&
 			    elem->data[3] == 0x04) {
+				lbs_deb_scan("got mesh IE\n");
 				bss->mesh = 1;
+			} else {
+				lbs_deb_scan("got generiec IE: "
+					"%02x:%02x:%02x:%02x, len %d\n",
+					elem->data[0], elem->data[1],
+					elem->data[2], elem->data[3],
+					elem->len);
 			}
 			break;
 
 		case MFIE_TYPE_RSN:
+			lbs_deb_scan("got RSN IE\n");
 			bss->rsn_ie_len = min(elem->len + 2, MAX_WPA_IE_LEN);
 			memcpy(bss->rsn_ie, elem, bss->rsn_ie_len);
-			lbs_deb_hex(LBS_DEB_SCAN, "process_bss: RSN_IE", bss->rsn_ie, elem->len);
+			lbs_deb_hex(LBS_DEB_SCAN, "process_bss: RSN_IE",
+				bss->rsn_ie, elem->len);
 			break;
 
 		default:
+			lbs_deb_scan("got IE 0x%04x, len %d\n",
+				elem->id, elem->len);
 			break;
 		}
 
@@ -1273,8 +1120,6 @@ int lbs_find_best_network_ssid(struct lbs_private *priv,
 	if (adapter->surpriseremoved)
 		goto out;
 
-	wait_event_interruptible(adapter->cmd_pending, !adapter->nr_cmd_pending);
-
 	found = lbs_find_best_ssid_in_list(adapter, preferred_mode);
 	if (found && (found->ssid_len > 0)) {
 		memcpy(out_ssid, &found->ssid, IW_ESSID_MAX_SIZE);
@@ -1288,36 +1133,6 @@ out:
 	return ret;
 }
 
-/**
- *  @brief Scan Network
- *
- *  @param dev          A pointer to net_device structure
- *  @param info         A pointer to iw_request_info structure
- *  @param vwrq         A pointer to iw_param structure
- *  @param extra        A pointer to extra data buf
- *
- *  @return             0 --success, otherwise fail
- */
-int lbs_set_scan(struct net_device *dev, struct iw_request_info *info,
-		  struct iw_param *vwrq, char *extra)
-{
-	struct lbs_private *priv = dev->priv;
-	struct lbs_adapter *adapter = priv->adapter;
-
-	lbs_deb_enter(LBS_DEB_SCAN);
-
-	if (!delayed_work_pending(&priv->scan_work)) {
-		queue_delayed_work(priv->work_thread, &priv->scan_work,
-		                   msecs_to_jiffies(50));
-	}
-
-	if (adapter->surpriseremoved)
-		return -1;
-
-	lbs_deb_leave(LBS_DEB_SCAN);
-	return 0;
-}
-
 
 /**
  *  @brief Send a scan command for all available channels filtered on a spec
@@ -1329,8 +1144,6 @@ int lbs_set_scan(struct net_device *dev, struct iw_request_info *info,
  *  @param ssid_len         Length of the SSID
  *  @param clear_ssid       Should existing scan results with this SSID
  *                          be cleared?
- *  @param prequestedssid   A pointer to AP's ssid
- *  @param keeppreviousscan Flag used to save/clear scan table before scan
  *
  *  @return                0-success, otherwise fail
  */
@@ -1357,7 +1170,6 @@ int lbs_send_specific_ssid_scan(struct lbs_private *priv,
 		ret = -1;
 		goto out;
 	}
-	wait_event_interruptible(adapter->cmd_pending, !adapter->nr_cmd_pending);
 
 out:
 	lbs_deb_leave_args(LBS_DEB_SCAN, "ret %d", ret);
@@ -1373,6 +1185,7 @@ out:
 /*                                                                   */
 /*********************************************************************/
 
+
 #define MAX_CUSTOM_LEN 64
 
 static inline char *lbs_translate_scan(struct lbs_private *priv,
@@ -1398,7 +1211,7 @@ static inline char *lbs_translate_scan(struct lbs_private *priv,
 		goto out;
 	}
 
-	/* First entry *MUST* be the AP BSSID */
+	/* First entry *MUST* be the BSSID */
 	iwe.cmd = SIOCGIWAP;
 	iwe.u.ap_addr.sa_family = ARPHRD_ETHER;
 	memcpy(iwe.u.ap_addr.sa_data, &bss->bssid, ETH_ALEN);
@@ -1528,6 +1341,55 @@ out:
 	return start;
 }
 
+
+/**
+ *  @brief Handle Scan Network ioctl
+ *
+ *  @param dev          A pointer to net_device structure
+ *  @param info         A pointer to iw_request_info structure
+ *  @param vwrq         A pointer to iw_param structure
+ *  @param extra        A pointer to extra data buf
+ *
+ *  @return             0 --success, otherwise fail
+ */
+int lbs_set_scan(struct net_device *dev, struct iw_request_info *info,
+		  struct iw_param *wrqu, char *extra)
+{
+	struct lbs_private *priv = dev->priv;
+	struct lbs_adapter *adapter = priv->adapter;
+
+	lbs_deb_enter(LBS_DEB_SCAN);
+
+	if (!netif_running(dev))
+		return -ENETDOWN;
+
+	/* mac80211 does this:
+	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
+	if (sdata->type != IEEE80211_IF_TYPE_xxx)
+		return -EOPNOTSUPP;
+
+	if (wrqu->data.length == sizeof(struct iw_scan_req) &&
+	    wrqu->data.flags & IW_SCAN_THIS_ESSID) {
+		req = (struct iw_scan_req *)extra;
+			ssid = req->essid;
+		ssid_len = req->essid_len;
+	}
+	*/
+
+	if (!delayed_work_pending(&priv->scan_work))
+		queue_delayed_work(priv->work_thread, &priv->scan_work,
+			msecs_to_jiffies(50));
+	/* set marker that currently a scan is taking place */
+	adapter->last_scanned_channel = -1;
+
+	if (adapter->surpriseremoved)
+		return -EIO;
+
+	lbs_deb_leave(LBS_DEB_SCAN);
+	return 0;
+}
+
+
 /**
  *  @brief  Handle Retrieve scan table ioctl
  *
@@ -1552,6 +1414,10 @@ int lbs_get_scan(struct net_device *dev, struct iw_request_info *info,
 
 	lbs_deb_enter(LBS_DEB_SCAN);
 
+	/* iwlist should wait until the current scan is finished */
+	if (adapter->last_scanned_channel)
+		return -EAGAIN;
+
 	/* Update RSSI if current BSS is a locally created ad-hoc BSS */
 	if ((adapter->mode == IW_MODE_ADHOC) && adapter->adhoccreate) {
 		lbs_prepare_and_send_command(priv, CMD_802_11_RSSI, 0,
@@ -1609,7 +1475,8 @@ int lbs_get_scan(struct net_device *dev, struct iw_request_info *info,
 /**
  *  @brief Prepare a scan command to be sent to the firmware
  *
- *  Called from lbs_prepare_and_send_command() in cmd.c
+ *  Called via lbs_prepare_and_send_command(priv, CMD_802_11_SCAN, ...)
+ *  from cmd.c
  *
  *  Sends a fixed lenght data part (specifying the BSS type and BSSID filters)
  *  as well as a variable number/length of TLVs to the firmware.
@@ -1623,7 +1490,7 @@ int lbs_get_scan(struct net_device *dev, struct iw_request_info *info,
  *  @return           0 or -1
  */
 int lbs_cmd_80211_scan(struct lbs_private *priv,
-			 struct cmd_ds_command *cmd, void *pdata_buf)
+	struct cmd_ds_command *cmd, void *pdata_buf)
 {
 	struct cmd_ds_802_11_scan *pscan = &cmd->params.scan;
 	struct lbs_scan_cmd_config *pscancfg = pdata_buf;
@@ -1635,32 +1502,14 @@ int lbs_cmd_80211_scan(struct lbs_private *priv,
 	memcpy(pscan->bssid, pscancfg->bssid, ETH_ALEN);
 	memcpy(pscan->tlvbuffer, pscancfg->tlvbuffer, pscancfg->tlvbufferlen);
 
-	cmd->command = cpu_to_le16(CMD_802_11_SCAN);
-
 	/* size is equal to the sizeof(fixed portions) + the TLV len + header */
 	cmd->size = cpu_to_le16(sizeof(pscan->bsstype) + ETH_ALEN
 				+ pscancfg->tlvbufferlen + S_DS_GEN);
 
-	lbs_deb_scan("SCAN_CMD: command 0x%04x, size %d, seqnum %d\n",
-		     le16_to_cpu(cmd->command), le16_to_cpu(cmd->size),
-		     le16_to_cpu(cmd->seqnum));
-
 	lbs_deb_leave(LBS_DEB_SCAN);
 	return 0;
 }
 
-static inline int is_same_network(struct bss_descriptor *src,
-				  struct bss_descriptor *dst)
-{
-	/* A network is only a duplicate if the channel, BSSID, and ESSID
-	 * all match.  We treat all <hidden> with the same BSSID and channel
-	 * as one network */
-	return ((src->ssid_len == dst->ssid_len) &&
-		(src->channel == dst->channel) &&
-		!compare_ether_addr(src->bssid, dst->bssid) &&
-		!memcmp(src->ssid, dst->ssid, src->ssid_len));
-}
-
 /**
  *  @brief This function handles the command response of scan
  *
@@ -1725,7 +1574,7 @@ int lbs_ret_80211_scan(struct lbs_private *priv, struct cmd_ds_command *resp)
 	lbs_deb_scan("SCAN_RESP: bssdescriptsize %d\n", bytesleft);
 
 	scanrespsize = le16_to_cpu(get_unaligned((u16*)&resp->size));
-	lbs_deb_scan("SCAN_RESP: returned %d AP before parsing\n",
+	lbs_deb_scan("SCAN_RESP: scan results %d\n",
 	       pscan->nr_sets);
 
 	pbssinfo = pscan->bssdesc_and_tlvbuffer;
@@ -1788,7 +1637,7 @@ int lbs_ret_80211_scan(struct lbs_private *priv, struct cmd_ds_command *resp)
 			continue;
 		}
 
-		lbs_deb_scan("SCAN_RESP: BSSID = %s\n",
+		lbs_deb_scan("SCAN_RESP: BSSID %s\n",
 			     print_mac(mac, new.bssid));
 
 		/* Copy the locally created newbssentry to the scan table */