Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next

Pull networking changes from David S Miller:

 1) Remove the ipv4 routing cache.  Now lookups go directly into the FIB
    trie and use prebuilt routes cached there.

    No more garbage collection, no more rDOS attacks on the routing
    cache.  Instead we now get predictable and consistent performance,
    no matter what the pattern of traffic we service.

    This has been almost 2 years in the making.  Special thanks to
    Julian Anastasov, Eric Dumazet, Steffen Klassert, and others who
    have helped along the way.

    I'm sure that with a change of this magnitude there will be some
    kind of fallout, but such things ought the be simple to fix at this
    point.  Luckily I'm not European so I'll be around all of August to
    fix things :-)

    The major stages of this work here are each fronted by a forced
    merge commit whose commit message contains a top-level description
    of the motivations and implementation issues.

 2) Pre-demux of established ipv4 TCP sockets, saves a route demux on
    input.

 3) TCP SYN/ACK performance tweaks from Eric Dumazet.

 4) Add namespace support for netfilter L4 conntrack helpers, from Gao
    Feng.

 5) Add config mechanism for Energy Efficient Ethernet to ethtool, from
    Yuval Mintz.

 6) Remove quadratic behavior from /proc/net/unix, from Eric Dumazet.

 7) Support for connection tracker helpers in userspace, from Pablo
    Neira Ayuso.

 8) Allow userspace driven TX load balancing functions in TEAM driver,
    from Jiri Pirko.

 9) Kill off NLMSG_PUT and RTA_PUT macros, more gross stuff with
    embedded gotos.

10) TCP Small Queues, essentially minimize the amount of TCP data queued
    up in the packet scheduler layer.  Whereas the existing BQL (Byte
    Queue Limits) limits the pkt_sched --> netdevice queuing levels,
    this controls the TCP --> pkt_sched queueing levels.

    From Eric Dumazet.

11) Reduce the number of get_page/put_page ops done on SKB fragments,
    from Alexander Duyck.

12) Implement protection against blind resets in TCP (RFC 5961), from
    Eric Dumazet.

13) Support the client side of TCP Fast Open, basically the ability to
    send data in the SYN exchange, from Yuchung Cheng.

    Basically, the sender queues up data with a sendmsg() call using
    MSG_FASTOPEN, then they do the connect() which emits the queued up
    fastopen data.

14) Avoid all the problems we get into in TCP when timers or PMTU events
    hit a locked socket.  The TCP Small Queues changes added a
    tcp_release_cb() that allows us to queue work up to the
    release_sock() caller, and that's what we use here too.  From Eric
    Dumazet.

15) Zero copy on TX support for TUN driver, from Michael S. Tsirkin.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1870 commits)
  genetlink: define lockdep_genl_is_held() when CONFIG_LOCKDEP
  r8169: revert "add byte queue limit support".
  ipv4: Change rt->rt_iif encoding.
  net: Make skb->skb_iif always track skb->dev
  ipv4: Prepare for change of rt->rt_iif encoding.
  ipv4: Remove all RTCF_DIRECTSRC handliing.
  ipv4: Really ignore ICMP address requests/replies.
  decnet: Don't set RTCF_DIRECTSRC.
  net/ipv4/ip_vti.c: Fix __rcu warnings detected by sparse.
  ipv4: Remove redundant assignment
  rds: set correct msg_namelen
  openvswitch: potential NULL deref in sample()
  tcp: dont drop MTU reduction indications
  bnx2x: Add new 57840 device IDs
  tcp: avoid oops in tcp_metrics and reset tcpm_stamp
  niu: Change niu_rbr_fill() to use unlikely() to check niu_rbr_add_page() return value
  niu: Fix to check for dma mapping errors.
  net: Fix references to out-of-scope variables in put_cmsg_compat()
  net: ethernet: davinci_emac: add pm_runtime support
  net: ethernet: davinci_emac: Remove unnecessary #include
  ...

1 files changed, 776 insertions, 0 deletions

diff --git a/drivers/net/wireless/ath/ath9k/antenna.c b/drivers/net/wireless/ath/ath9k/antenna.c
new file mode 100644
index 000000000000..bbcfeb3b2a60
--- /dev/null
+++ b/drivers/net/wireless/ath/ath9k/antenna.c
@@ -0,0 +1,776 @@
+/*
+ * Copyright (c) 2012 Qualcomm Atheros, Inc.
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include "ath9k.h"
+
+static inline bool ath_is_alt_ant_ratio_better(int alt_ratio, int maxdelta,
+					       int mindelta, int main_rssi_avg,
+					       int alt_rssi_avg, int pkt_count)
+{
+	return (((alt_ratio >= ATH_ANT_DIV_COMB_ALT_ANT_RATIO2) &&
+		 (alt_rssi_avg > main_rssi_avg + maxdelta)) ||
+		(alt_rssi_avg > main_rssi_avg + mindelta)) && (pkt_count > 50);
+}
+
+static inline bool ath_ant_div_comb_alt_check(u8 div_group, int alt_ratio,
+					      int curr_main_set, int curr_alt_set,
+					      int alt_rssi_avg, int main_rssi_avg)
+{
+	bool result = false;
+	switch (div_group) {
+	case 0:
+		if (alt_ratio > ATH_ANT_DIV_COMB_ALT_ANT_RATIO)
+			result = true;
+		break;
+	case 1:
+	case 2:
+		if ((((curr_main_set == ATH_ANT_DIV_COMB_LNA2) &&
+		      (curr_alt_set == ATH_ANT_DIV_COMB_LNA1) &&
+		      (alt_rssi_avg >= (main_rssi_avg - 5))) ||
+		     ((curr_main_set == ATH_ANT_DIV_COMB_LNA1) &&
+		      (curr_alt_set == ATH_ANT_DIV_COMB_LNA2) &&
+		      (alt_rssi_avg >= (main_rssi_avg - 2)))) &&
+		    (alt_rssi_avg >= 4))
+			result = true;
+		else
+			result = false;
+		break;
+	}
+
+	return result;
+}
+
+static void ath_lnaconf_alt_good_scan(struct ath_ant_comb *antcomb,
+				      struct ath_hw_antcomb_conf ant_conf,
+				      int main_rssi_avg)
+{
+	antcomb->quick_scan_cnt = 0;
+
+	if (ant_conf.main_lna_conf == ATH_ANT_DIV_COMB_LNA2)
+		antcomb->rssi_lna2 = main_rssi_avg;
+	else if (ant_conf.main_lna_conf == ATH_ANT_DIV_COMB_LNA1)
+		antcomb->rssi_lna1 = main_rssi_avg;
+
+	switch ((ant_conf.main_lna_conf << 4) | ant_conf.alt_lna_conf) {
+	case 0x10: /* LNA2 A-B */
+		antcomb->main_conf = ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
+		antcomb->first_quick_scan_conf =
+			ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
+		antcomb->second_quick_scan_conf = ATH_ANT_DIV_COMB_LNA1;
+		break;
+	case 0x20: /* LNA1 A-B */
+		antcomb->main_conf = ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
+		antcomb->first_quick_scan_conf =
+			ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
+		antcomb->second_quick_scan_conf = ATH_ANT_DIV_COMB_LNA2;
+		break;
+	case 0x21: /* LNA1 LNA2 */
+		antcomb->main_conf = ATH_ANT_DIV_COMB_LNA2;
+		antcomb->first_quick_scan_conf =
+			ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
+		antcomb->second_quick_scan_conf =
+			ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
+		break;
+	case 0x12: /* LNA2 LNA1 */
+		antcomb->main_conf = ATH_ANT_DIV_COMB_LNA1;
+		antcomb->first_quick_scan_conf =
+			ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
+		antcomb->second_quick_scan_conf =
+			ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
+		break;
+	case 0x13: /* LNA2 A+B */
+		antcomb->main_conf = ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
+		antcomb->first_quick_scan_conf =
+			ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
+		antcomb->second_quick_scan_conf = ATH_ANT_DIV_COMB_LNA1;
+		break;
+	case 0x23: /* LNA1 A+B */
+		antcomb->main_conf = ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
+		antcomb->first_quick_scan_conf =
+			ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
+		antcomb->second_quick_scan_conf = ATH_ANT_DIV_COMB_LNA2;
+		break;
+	default:
+		break;
+	}
+}
+
+static void ath_select_ant_div_from_quick_scan(struct ath_ant_comb *antcomb,
+				       struct ath_hw_antcomb_conf *div_ant_conf,
+				       int main_rssi_avg, int alt_rssi_avg,
+				       int alt_ratio)
+{
+	/* alt_good */
+	switch (antcomb->quick_scan_cnt) {
+	case 0:
+		/* set alt to main, and alt to first conf */
+		div_ant_conf->main_lna_conf = antcomb->main_conf;
+		div_ant_conf->alt_lna_conf = antcomb->first_quick_scan_conf;
+		break;
+	case 1:
+		/* set alt to main, and alt to first conf */
+		div_ant_conf->main_lna_conf = antcomb->main_conf;
+		div_ant_conf->alt_lna_conf = antcomb->second_quick_scan_conf;
+		antcomb->rssi_first = main_rssi_avg;
+		antcomb->rssi_second = alt_rssi_avg;
+
+		if (antcomb->main_conf == ATH_ANT_DIV_COMB_LNA1) {
+			/* main is LNA1 */
+			if (ath_is_alt_ant_ratio_better(alt_ratio,
+						ATH_ANT_DIV_COMB_LNA1_DELTA_HI,
+						ATH_ANT_DIV_COMB_LNA1_DELTA_LOW,
+						main_rssi_avg, alt_rssi_avg,
+						antcomb->total_pkt_count))
+				antcomb->first_ratio = true;
+			else
+				antcomb->first_ratio = false;
+		} else if (antcomb->main_conf == ATH_ANT_DIV_COMB_LNA2) {
+			if (ath_is_alt_ant_ratio_better(alt_ratio,
+						ATH_ANT_DIV_COMB_LNA1_DELTA_MID,
+						ATH_ANT_DIV_COMB_LNA1_DELTA_LOW,
+						main_rssi_avg, alt_rssi_avg,
+						antcomb->total_pkt_count))
+				antcomb->first_ratio = true;
+			else
+				antcomb->first_ratio = false;
+		} else {
+			if ((((alt_ratio >= ATH_ANT_DIV_COMB_ALT_ANT_RATIO2) &&
+			      (alt_rssi_avg > main_rssi_avg +
+			       ATH_ANT_DIV_COMB_LNA1_DELTA_HI)) ||
+			     (alt_rssi_avg > main_rssi_avg)) &&
+			    (antcomb->total_pkt_count > 50))
+				antcomb->first_ratio = true;
+			else
+				antcomb->first_ratio = false;
+		}
+		break;
+	case 2:
+		antcomb->alt_good = false;
+		antcomb->scan_not_start = false;
+		antcomb->scan = false;
+		antcomb->rssi_first = main_rssi_avg;
+		antcomb->rssi_third = alt_rssi_avg;
+
+		if (antcomb->second_quick_scan_conf == ATH_ANT_DIV_COMB_LNA1)
+			antcomb->rssi_lna1 = alt_rssi_avg;
+		else if (antcomb->second_quick_scan_conf ==
+			 ATH_ANT_DIV_COMB_LNA2)
+			antcomb->rssi_lna2 = alt_rssi_avg;
+		else if (antcomb->second_quick_scan_conf ==
+			 ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2) {
+			if (antcomb->main_conf == ATH_ANT_DIV_COMB_LNA2)
+				antcomb->rssi_lna2 = main_rssi_avg;
+			else if (antcomb->main_conf == ATH_ANT_DIV_COMB_LNA1)
+				antcomb->rssi_lna1 = main_rssi_avg;
+		}
+
+		if (antcomb->rssi_lna2 > antcomb->rssi_lna1 +
+		    ATH_ANT_DIV_COMB_LNA1_LNA2_SWITCH_DELTA)
+			div_ant_conf->main_lna_conf = ATH_ANT_DIV_COMB_LNA2;
+		else
+			div_ant_conf->main_lna_conf = ATH_ANT_DIV_COMB_LNA1;
+
+		if (antcomb->main_conf == ATH_ANT_DIV_COMB_LNA1) {
+			if (ath_is_alt_ant_ratio_better(alt_ratio,
+						ATH_ANT_DIV_COMB_LNA1_DELTA_HI,
+						ATH_ANT_DIV_COMB_LNA1_DELTA_LOW,
+						main_rssi_avg, alt_rssi_avg,
+						antcomb->total_pkt_count))
+				antcomb->second_ratio = true;
+			else
+				antcomb->second_ratio = false;
+		} else if (antcomb->main_conf == ATH_ANT_DIV_COMB_LNA2) {
+			if (ath_is_alt_ant_ratio_better(alt_ratio,
+						ATH_ANT_DIV_COMB_LNA1_DELTA_MID,
+						ATH_ANT_DIV_COMB_LNA1_DELTA_LOW,
+						main_rssi_avg, alt_rssi_avg,
+						antcomb->total_pkt_count))
+				antcomb->second_ratio = true;
+			else
+				antcomb->second_ratio = false;
+		} else {
+			if ((((alt_ratio >= ATH_ANT_DIV_COMB_ALT_ANT_RATIO2) &&
+			      (alt_rssi_avg > main_rssi_avg +
+			       ATH_ANT_DIV_COMB_LNA1_DELTA_HI)) ||
+			     (alt_rssi_avg > main_rssi_avg)) &&
+			    (antcomb->total_pkt_count > 50))
+				antcomb->second_ratio = true;
+			else
+				antcomb->second_ratio = false;
+		}
+
+		/* set alt to the conf with maximun ratio */
+		if (antcomb->first_ratio && antcomb->second_ratio) {
+			if (antcomb->rssi_second > antcomb->rssi_third) {
+				/* first alt*/
+				if ((antcomb->first_quick_scan_conf ==
+				    ATH_ANT_DIV_COMB_LNA1) ||
+				    (antcomb->first_quick_scan_conf ==
+				    ATH_ANT_DIV_COMB_LNA2))
+					/* Set alt LNA1 or LNA2*/
+					if (div_ant_conf->main_lna_conf ==
+					    ATH_ANT_DIV_COMB_LNA2)
+						div_ant_conf->alt_lna_conf =
+							ATH_ANT_DIV_COMB_LNA1;
+					else
+						div_ant_conf->alt_lna_conf =
+							ATH_ANT_DIV_COMB_LNA2;
+				else
+					/* Set alt to A+B or A-B */
+					div_ant_conf->alt_lna_conf =
+						antcomb->first_quick_scan_conf;
+			} else if ((antcomb->second_quick_scan_conf ==
+				   ATH_ANT_DIV_COMB_LNA1) ||
+				   (antcomb->second_quick_scan_conf ==
+				   ATH_ANT_DIV_COMB_LNA2)) {
+				/* Set alt LNA1 or LNA2 */
+				if (div_ant_conf->main_lna_conf ==
+				    ATH_ANT_DIV_COMB_LNA2)
+					div_ant_conf->alt_lna_conf =
+						ATH_ANT_DIV_COMB_LNA1;
+				else
+					div_ant_conf->alt_lna_conf =
+						ATH_ANT_DIV_COMB_LNA2;
+			} else {
+				/* Set alt to A+B or A-B */
+				div_ant_conf->alt_lna_conf =
+					antcomb->second_quick_scan_conf;
+			}
+		} else if (antcomb->first_ratio) {
+			/* first alt */
+			if ((antcomb->first_quick_scan_conf ==
+			    ATH_ANT_DIV_COMB_LNA1) ||
+			    (antcomb->first_quick_scan_conf ==
+			    ATH_ANT_DIV_COMB_LNA2))
+					/* Set alt LNA1 or LNA2 */
+				if (div_ant_conf->main_lna_conf ==
+				    ATH_ANT_DIV_COMB_LNA2)
+					div_ant_conf->alt_lna_conf =
+							ATH_ANT_DIV_COMB_LNA1;
+				else
+					div_ant_conf->alt_lna_conf =
+							ATH_ANT_DIV_COMB_LNA2;
+			else
+				/* Set alt to A+B or A-B */
+				div_ant_conf->alt_lna_conf =
+						antcomb->first_quick_scan_conf;
+		} else if (antcomb->second_ratio) {
+				/* second alt */
+			if ((antcomb->second_quick_scan_conf ==
+			    ATH_ANT_DIV_COMB_LNA1) ||
+			    (antcomb->second_quick_scan_conf ==
+			    ATH_ANT_DIV_COMB_LNA2))
+				/* Set alt LNA1 or LNA2 */
+				if (div_ant_conf->main_lna_conf ==
+				    ATH_ANT_DIV_COMB_LNA2)
+					div_ant_conf->alt_lna_conf =
+						ATH_ANT_DIV_COMB_LNA1;
+				else
+					div_ant_conf->alt_lna_conf =
+						ATH_ANT_DIV_COMB_LNA2;
+			else
+				/* Set alt to A+B or A-B */
+				div_ant_conf->alt_lna_conf =
+						antcomb->second_quick_scan_conf;
+		} else {
+			/* main is largest */
+			if ((antcomb->main_conf == ATH_ANT_DIV_COMB_LNA1) ||
+			    (antcomb->main_conf == ATH_ANT_DIV_COMB_LNA2))
+				/* Set alt LNA1 or LNA2 */
+				if (div_ant_conf->main_lna_conf ==
+				    ATH_ANT_DIV_COMB_LNA2)
+					div_ant_conf->alt_lna_conf =
+							ATH_ANT_DIV_COMB_LNA1;
+				else
+					div_ant_conf->alt_lna_conf =
+							ATH_ANT_DIV_COMB_LNA2;
+			else
+				/* Set alt to A+B or A-B */
+				div_ant_conf->alt_lna_conf = antcomb->main_conf;
+		}
+		break;
+	default:
+		break;
+	}
+}
+
+static void ath_ant_div_conf_fast_divbias(struct ath_hw_antcomb_conf *ant_conf,
+					  struct ath_ant_comb *antcomb,
+					  int alt_ratio)
+{
+	if (ant_conf->div_group == 0) {
+		/* Adjust the fast_div_bias based on main and alt lna conf */
+		switch ((ant_conf->main_lna_conf << 4) |
+				ant_conf->alt_lna_conf) {
+		case 0x01: /* A-B LNA2 */
+			ant_conf->fast_div_bias = 0x3b;
+			break;
+		case 0x02: /* A-B LNA1 */
+			ant_conf->fast_div_bias = 0x3d;
+			break;
+		case 0x03: /* A-B A+B */
+			ant_conf->fast_div_bias = 0x1;
+			break;
+		case 0x10: /* LNA2 A-B */
+			ant_conf->fast_div_bias = 0x7;
+			break;
+		case 0x12: /* LNA2 LNA1 */
+			ant_conf->fast_div_bias = 0x2;
+			break;
+		case 0x13: /* LNA2 A+B */
+			ant_conf->fast_div_bias = 0x7;
+			break;
+		case 0x20: /* LNA1 A-B */
+			ant_conf->fast_div_bias = 0x6;
+			break;
+		case 0x21: /* LNA1 LNA2 */
+			ant_conf->fast_div_bias = 0x0;
+			break;
+		case 0x23: /* LNA1 A+B */
+			ant_conf->fast_div_bias = 0x6;
+			break;
+		case 0x30: /* A+B A-B */
+			ant_conf->fast_div_bias = 0x1;
+			break;
+		case 0x31: /* A+B LNA2 */
+			ant_conf->fast_div_bias = 0x3b;
+			break;
+		case 0x32: /* A+B LNA1 */
+			ant_conf->fast_div_bias = 0x3d;
+			break;
+		default:
+			break;
+		}
+	} else if (ant_conf->div_group == 1) {
+		/* Adjust the fast_div_bias based on main and alt_lna_conf */
+		switch ((ant_conf->main_lna_conf << 4) |
+			ant_conf->alt_lna_conf) {
+		case 0x01: /* A-B LNA2 */
+			ant_conf->fast_div_bias = 0x1;
+			ant_conf->main_gaintb = 0;
+			ant_conf->alt_gaintb = 0;
+			break;
+		case 0x02: /* A-B LNA1 */
+			ant_conf->fast_div_bias = 0x1;
+			ant_conf->main_gaintb = 0;
+			ant_conf->alt_gaintb = 0;
+			break;
+		case 0x03: /* A-B A+B */
+			ant_conf->fast_div_bias = 0x1;
+			ant_conf->main_gaintb = 0;
+			ant_conf->alt_gaintb = 0;
+			break;
+		case 0x10: /* LNA2 A-B */
+			if (!(antcomb->scan) &&
+			    (alt_ratio > ATH_ANT_DIV_COMB_ALT_ANT_RATIO))
+				ant_conf->fast_div_bias = 0x3f;
+			else
+				ant_conf->fast_div_bias = 0x1;
+			ant_conf->main_gaintb = 0;
+			ant_conf->alt_gaintb = 0;
+			break;
+		case 0x12: /* LNA2 LNA1 */
+			ant_conf->fast_div_bias = 0x1;
+			ant_conf->main_gaintb = 0;
+			ant_conf->alt_gaintb = 0;
+			break;
+		case 0x13: /* LNA2 A+B */
+			if (!(antcomb->scan) &&
+			    (alt_ratio > ATH_ANT_DIV_COMB_ALT_ANT_RATIO))
+				ant_conf->fast_div_bias = 0x3f;
+			else
+				ant_conf->fast_div_bias = 0x1;
+			ant_conf->main_gaintb = 0;
+			ant_conf->alt_gaintb = 0;
+			break;
+		case 0x20: /* LNA1 A-B */
+			if (!(antcomb->scan) &&
+			    (alt_ratio > ATH_ANT_DIV_COMB_ALT_ANT_RATIO))
+				ant_conf->fast_div_bias = 0x3f;
+			else
+				ant_conf->fast_div_bias = 0x1;
+			ant_conf->main_gaintb = 0;
+			ant_conf->alt_gaintb = 0;
+			break;
+		case 0x21: /* LNA1 LNA2 */
+			ant_conf->fast_div_bias = 0x1;
+			ant_conf->main_gaintb = 0;
+			ant_conf->alt_gaintb = 0;
+			break;
+		case 0x23: /* LNA1 A+B */
+			if (!(antcomb->scan) &&
+			    (alt_ratio > ATH_ANT_DIV_COMB_ALT_ANT_RATIO))
+				ant_conf->fast_div_bias = 0x3f;
+			else
+				ant_conf->fast_div_bias = 0x1;
+			ant_conf->main_gaintb = 0;
+			ant_conf->alt_gaintb = 0;
+			break;
+		case 0x30: /* A+B A-B */
+			ant_conf->fast_div_bias = 0x1;
+			ant_conf->main_gaintb = 0;
+			ant_conf->alt_gaintb = 0;
+			break;
+		case 0x31: /* A+B LNA2 */
+			ant_conf->fast_div_bias = 0x1;
+			ant_conf->main_gaintb = 0;
+			ant_conf->alt_gaintb = 0;
+			break;
+		case 0x32: /* A+B LNA1 */
+			ant_conf->fast_div_bias = 0x1;
+			ant_conf->main_gaintb = 0;
+			ant_conf->alt_gaintb = 0;
+			break;
+		default:
+			break;
+		}
+	} else if (ant_conf->div_group == 2) {
+		/* Adjust the fast_div_bias based on main and alt_lna_conf */
+		switch ((ant_conf->main_lna_conf << 4) |
+				ant_conf->alt_lna_conf) {
+		case 0x01: /* A-B LNA2 */
+			ant_conf->fast_div_bias = 0x1;
+			ant_conf->main_gaintb = 0;
+			ant_conf->alt_gaintb = 0;
+			break;
+		case 0x02: /* A-B LNA1 */
+			ant_conf->fast_div_bias = 0x1;
+			ant_conf->main_gaintb = 0;
+			ant_conf->alt_gaintb = 0;
+			break;
+		case 0x03: /* A-B A+B */
+			ant_conf->fast_div_bias = 0x1;
+			ant_conf->main_gaintb = 0;
+			ant_conf->alt_gaintb = 0;
+			break;
+		case 0x10: /* LNA2 A-B */
+			if (!(antcomb->scan) &&
+				(alt_ratio > ATH_ANT_DIV_COMB_ALT_ANT_RATIO))
+				ant_conf->fast_div_bias = 0x1;
+			else
+				ant_conf->fast_div_bias = 0x2;
+			ant_conf->main_gaintb = 0;
+			ant_conf->alt_gaintb = 0;
+			break;
+		case 0x12: /* LNA2 LNA1 */
+			ant_conf->fast_div_bias = 0x1;
+			ant_conf->main_gaintb = 0;
+			ant_conf->alt_gaintb = 0;
+			break;
+		case 0x13: /* LNA2 A+B */
+			if (!(antcomb->scan) &&
+				(alt_ratio > ATH_ANT_DIV_COMB_ALT_ANT_RATIO))
+				ant_conf->fast_div_bias = 0x1;
+			else
+				ant_conf->fast_div_bias = 0x2;
+			ant_conf->main_gaintb = 0;
+			ant_conf->alt_gaintb = 0;
+			break;
+		case 0x20: /* LNA1 A-B */
+			if (!(antcomb->scan) &&
+				(alt_ratio > ATH_ANT_DIV_COMB_ALT_ANT_RATIO))
+				ant_conf->fast_div_bias = 0x1;
+			else
+				ant_conf->fast_div_bias = 0x2;
+			ant_conf->main_gaintb = 0;
+			ant_conf->alt_gaintb = 0;
+			break;
+		case 0x21: /* LNA1 LNA2 */
+			ant_conf->fast_div_bias = 0x1;
+			ant_conf->main_gaintb = 0;
+			ant_conf->alt_gaintb = 0;
+			break;
+		case 0x23: /* LNA1 A+B */
+			if (!(antcomb->scan) &&
+				(alt_ratio > ATH_ANT_DIV_COMB_ALT_ANT_RATIO))
+				ant_conf->fast_div_bias = 0x1;
+			else
+				ant_conf->fast_div_bias = 0x2;
+			ant_conf->main_gaintb = 0;
+			ant_conf->alt_gaintb = 0;
+			break;
+		case 0x30: /* A+B A-B */
+			ant_conf->fast_div_bias = 0x1;
+			ant_conf->main_gaintb = 0;
+			ant_conf->alt_gaintb = 0;
+			break;
+		case 0x31: /* A+B LNA2 */
+			ant_conf->fast_div_bias = 0x1;
+			ant_conf->main_gaintb = 0;
+			ant_conf->alt_gaintb = 0;
+			break;
+		case 0x32: /* A+B LNA1 */
+			ant_conf->fast_div_bias = 0x1;
+			ant_conf->main_gaintb = 0;
+			ant_conf->alt_gaintb = 0;
+			break;
+		default:
+			break;
+		}
+	}
+}
+
+void ath_ant_comb_scan(struct ath_softc *sc, struct ath_rx_status *rs)
+{
+	struct ath_hw_antcomb_conf div_ant_conf;
+	struct ath_ant_comb *antcomb = &sc->ant_comb;
+	int alt_ratio = 0, alt_rssi_avg = 0, main_rssi_avg = 0, curr_alt_set;
+	int curr_main_set;
+	int main_rssi = rs->rs_rssi_ctl0;
+	int alt_rssi = rs->rs_rssi_ctl1;
+	int rx_ant_conf,  main_ant_conf;
+	bool short_scan = false;
+
+	rx_ant_conf = (rs->rs_rssi_ctl2 >> ATH_ANT_RX_CURRENT_SHIFT) &
+		       ATH_ANT_RX_MASK;
+	main_ant_conf = (rs->rs_rssi_ctl2 >> ATH_ANT_RX_MAIN_SHIFT) &
+			 ATH_ANT_RX_MASK;
+
+	/* Record packet only when both main_rssi and  alt_rssi is positive */
+	if (main_rssi > 0 && alt_rssi > 0) {
+		antcomb->total_pkt_count++;
+		antcomb->main_total_rssi += main_rssi;
+		antcomb->alt_total_rssi  += alt_rssi;
+		if (main_ant_conf == rx_ant_conf)
+			antcomb->main_recv_cnt++;
+		else
+			antcomb->alt_recv_cnt++;
+	}
+
+	/* Short scan check */
+	if (antcomb->scan && antcomb->alt_good) {
+		if (time_after(jiffies, antcomb->scan_start_time +
+		    msecs_to_jiffies(ATH_ANT_DIV_COMB_SHORT_SCAN_INTR)))
+			short_scan = true;
+		else
+			if (antcomb->total_pkt_count ==
+			    ATH_ANT_DIV_COMB_SHORT_SCAN_PKTCOUNT) {
+				alt_ratio = ((antcomb->alt_recv_cnt * 100) /
+					    antcomb->total_pkt_count);
+				if (alt_ratio < ATH_ANT_DIV_COMB_ALT_ANT_RATIO)
+					short_scan = true;
+			}
+	}
+
+	if (((antcomb->total_pkt_count < ATH_ANT_DIV_COMB_MAX_PKTCOUNT) ||
+	    rs->rs_moreaggr) && !short_scan)
+		return;
+
+	if (antcomb->total_pkt_count) {
+		alt_ratio = ((antcomb->alt_recv_cnt * 100) /
+			     antcomb->total_pkt_count);
+		main_rssi_avg = (antcomb->main_total_rssi /
+				 antcomb->total_pkt_count);
+		alt_rssi_avg = (antcomb->alt_total_rssi /
+				 antcomb->total_pkt_count);
+	}
+
+
+	ath9k_hw_antdiv_comb_conf_get(sc->sc_ah, &div_ant_conf);
+	curr_alt_set = div_ant_conf.alt_lna_conf;
+	curr_main_set = div_ant_conf.main_lna_conf;
+
+	antcomb->count++;
+
+	if (antcomb->count == ATH_ANT_DIV_COMB_MAX_COUNT) {
+		if (alt_ratio > ATH_ANT_DIV_COMB_ALT_ANT_RATIO) {
+			ath_lnaconf_alt_good_scan(antcomb, div_ant_conf,
+						  main_rssi_avg);
+			antcomb->alt_good = true;
+		} else {
+			antcomb->alt_good = false;
+		}
+
+		antcomb->count = 0;
+		antcomb->scan = true;
+		antcomb->scan_not_start = true;
+	}
+
+	if (!antcomb->scan) {
+		if (ath_ant_div_comb_alt_check(div_ant_conf.div_group,
+					alt_ratio, curr_main_set, curr_alt_set,
+					alt_rssi_avg, main_rssi_avg)) {
+			if (curr_alt_set == ATH_ANT_DIV_COMB_LNA2) {
+				/* Switch main and alt LNA */
+				div_ant_conf.main_lna_conf =
+						ATH_ANT_DIV_COMB_LNA2;
+				div_ant_conf.alt_lna_conf  =
+						ATH_ANT_DIV_COMB_LNA1;
+			} else if (curr_alt_set == ATH_ANT_DIV_COMB_LNA1) {
+				div_ant_conf.main_lna_conf =
+						ATH_ANT_DIV_COMB_LNA1;
+				div_ant_conf.alt_lna_conf  =
+						ATH_ANT_DIV_COMB_LNA2;
+			}
+
+			goto div_comb_done;
+		} else if ((curr_alt_set != ATH_ANT_DIV_COMB_LNA1) &&
+			   (curr_alt_set != ATH_ANT_DIV_COMB_LNA2)) {
+			/* Set alt to another LNA */
+			if (curr_main_set == ATH_ANT_DIV_COMB_LNA2)
+				div_ant_conf.alt_lna_conf =
+						ATH_ANT_DIV_COMB_LNA1;
+			else if (curr_main_set == ATH_ANT_DIV_COMB_LNA1)
+				div_ant_conf.alt_lna_conf =
+						ATH_ANT_DIV_COMB_LNA2;
+
+			goto div_comb_done;
+		}
+
+		if ((alt_rssi_avg < (main_rssi_avg +
+				     div_ant_conf.lna1_lna2_delta)))
+			goto div_comb_done;
+	}
+
+	if (!antcomb->scan_not_start) {
+		switch (curr_alt_set) {
+		case ATH_ANT_DIV_COMB_LNA2:
+			antcomb->rssi_lna2 = alt_rssi_avg;
+			antcomb->rssi_lna1 = main_rssi_avg;
+			antcomb->scan = true;
+			/* set to A+B */
+			div_ant_conf.main_lna_conf =
+				ATH_ANT_DIV_COMB_LNA1;
+			div_ant_conf.alt_lna_conf  =
+				ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
+			break;
+		case ATH_ANT_DIV_COMB_LNA1:
+			antcomb->rssi_lna1 = alt_rssi_avg;
+			antcomb->rssi_lna2 = main_rssi_avg;
+			antcomb->scan = true;
+			/* set to A+B */
+			div_ant_conf.main_lna_conf = ATH_ANT_DIV_COMB_LNA2;
+			div_ant_conf.alt_lna_conf  =
+				ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
+			break;
+		case ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2:
+			antcomb->rssi_add = alt_rssi_avg;
+			antcomb->scan = true;
+			/* set to A-B */
+			div_ant_conf.alt_lna_conf =
+				ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
+			break;
+		case ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2:
+			antcomb->rssi_sub = alt_rssi_avg;
+			antcomb->scan = false;
+			if (antcomb->rssi_lna2 >
+			    (antcomb->rssi_lna1 +
+			    ATH_ANT_DIV_COMB_LNA1_LNA2_SWITCH_DELTA)) {
+				/* use LNA2 as main LNA */
+				if ((antcomb->rssi_add > antcomb->rssi_lna1) &&
+				    (antcomb->rssi_add > antcomb->rssi_sub)) {
+					/* set to A+B */
+					div_ant_conf.main_lna_conf =
+						ATH_ANT_DIV_COMB_LNA2;
+					div_ant_conf.alt_lna_conf  =
+						ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
+				} else if (antcomb->rssi_sub >
+					   antcomb->rssi_lna1) {
+					/* set to A-B */
+					div_ant_conf.main_lna_conf =
+						ATH_ANT_DIV_COMB_LNA2;
+					div_ant_conf.alt_lna_conf =
+						ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
+				} else {
+					/* set to LNA1 */
+					div_ant_conf.main_lna_conf =
+						ATH_ANT_DIV_COMB_LNA2;
+					div_ant_conf.alt_lna_conf =
+						ATH_ANT_DIV_COMB_LNA1;
+				}
+			} else {
+				/* use LNA1 as main LNA */
+				if ((antcomb->rssi_add > antcomb->rssi_lna2) &&
+				    (antcomb->rssi_add > antcomb->rssi_sub)) {
+					/* set to A+B */
+					div_ant_conf.main_lna_conf =
+						ATH_ANT_DIV_COMB_LNA1;
+					div_ant_conf.alt_lna_conf  =
+						ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
+				} else if (antcomb->rssi_sub >
+					   antcomb->rssi_lna1) {
+					/* set to A-B */
+					div_ant_conf.main_lna_conf =
+						ATH_ANT_DIV_COMB_LNA1;
+					div_ant_conf.alt_lna_conf =
+						ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
+				} else {
+					/* set to LNA2 */
+					div_ant_conf.main_lna_conf =
+						ATH_ANT_DIV_COMB_LNA1;
+					div_ant_conf.alt_lna_conf =
+						ATH_ANT_DIV_COMB_LNA2;
+				}
+			}
+			break;
+		default:
+			break;
+		}
+	} else {
+		if (!antcomb->alt_good) {
+			antcomb->scan_not_start = false;
+			/* Set alt to another LNA */
+			if (curr_main_set == ATH_ANT_DIV_COMB_LNA2) {
+				div_ant_conf.main_lna_conf =
+						ATH_ANT_DIV_COMB_LNA2;
+				div_ant_conf.alt_lna_conf =
+						ATH_ANT_DIV_COMB_LNA1;
+			} else if (curr_main_set == ATH_ANT_DIV_COMB_LNA1) {
+				div_ant_conf.main_lna_conf =
+						ATH_ANT_DIV_COMB_LNA1;
+				div_ant_conf.alt_lna_conf =
+						ATH_ANT_DIV_COMB_LNA2;
+			}
+			goto div_comb_done;
+		}
+	}
+
+	ath_select_ant_div_from_quick_scan(antcomb, &div_ant_conf,
+					   main_rssi_avg, alt_rssi_avg,
+					   alt_ratio);
+
+	antcomb->quick_scan_cnt++;
+
+div_comb_done:
+	ath_ant_div_conf_fast_divbias(&div_ant_conf, antcomb, alt_ratio);
+	ath9k_hw_antdiv_comb_conf_set(sc->sc_ah, &div_ant_conf);
+
+	antcomb->scan_start_time = jiffies;
+	antcomb->total_pkt_count = 0;
+	antcomb->main_total_rssi = 0;
+	antcomb->alt_total_rssi = 0;
+	antcomb->main_recv_cnt = 0;
+	antcomb->alt_recv_cnt = 0;
+}
+
+void ath_ant_comb_update(struct ath_softc *sc)
+{
+	struct ath_hw *ah = sc->sc_ah;
+	struct ath_hw_antcomb_conf div_ant_conf;
+	u8 lna_conf;
+
+	ath9k_hw_antdiv_comb_conf_get(ah, &div_ant_conf);
+
+	if (sc->ant_rx == 1)
+		lna_conf = ATH_ANT_DIV_COMB_LNA1;
+	else
+		lna_conf = ATH_ANT_DIV_COMB_LNA2;
+
+	div_ant_conf.main_lna_conf = lna_conf;
+	div_ant_conf.alt_lna_conf = lna_conf;
+
+	ath9k_hw_antdiv_comb_conf_set(ah, &div_ant_conf);
+}