[ 3.5.y.z extended stable ] Patch "ath9k: Use minstrel rate control by default" has been added to staging queue

[Luis Henriques]

This is a note to let you know that I have just added a patch titled

    ath9k: Use minstrel rate control by default

to the linux-3.5.y-queue branch of the 3.5.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.5.y-queue

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.5.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

>From 13684ba05cb8e63c1758a6f52413917ae0ec9db9 Mon Sep 17 00:00:00 2001
From: Sujith Manoharan <c_manoha at qca.qualcomm.com>
Date: Thu, 6 Jun 2013 10:06:29 +0530
Subject: [PATCH] ath9k: Use minstrel rate control by default

commit 5efac94999ff218e0101f67a059e44abb4b0b523 upstream.

The ath9k rate control algorithm has various architectural
issues that make it a poor fit in scenarios like congested
environments etc.

An example: https://bugzilla.redhat.com/show_bug.cgi?id=927191

Change the default to minstrel which is more robust in such cases.
The ath9k RC code is left in the driver for now, maybe it can
be removed altogether later on.

Cc: Jouni Malinen <jouni at qca.qualcomm.com>
Cc: Linus Torvalds <torvalds at linux-foundation.org>
Signed-off-by: Sujith Manoharan <c_manoha at qca.qualcomm.com>
Signed-off-by: John W. Linville <linville at tuxdriver.com>
[ luis: backport to 3.5: adjust context ]
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 drivers/net/wireless/ath/ath9k/Kconfig  | 10 +++++++---
 drivers/net/wireless/ath/ath9k/Makefile |  2 +-
 drivers/net/wireless/ath/ath9k/init.c   |  4 ----
 drivers/net/wireless/ath/ath9k/rc.h     |  2 +-
 4 files changed, 9 insertions(+), 9 deletions(-)

diff --git a/drivers/net/wireless/ath/ath9k/Kconfig b/drivers/net/wireless/ath/ath9k/Kconfig
index e507e78..3b8c930 100644
--- a/drivers/net/wireless/ath/ath9k/Kconfig
+++ b/drivers/net/wireless/ath/ath9k/Kconfig
@@ -89,13 +89,17 @@ config ATH9K_MAC_DEBUG
 	  This option enables collection of statistics for Rx/Tx status
 	  data and some other MAC related statistics

-config ATH9K_RATE_CONTROL
+config ATH9K_LEGACY_RATE_CONTROL
 	bool "Atheros ath9k rate control"
 	depends on ATH9K
-	default y
+	default n
 	---help---
 	  Say Y, if you want to use the ath9k specific rate control
-	  module instead of minstrel_ht.
+	  module instead of minstrel_ht. Be warned that there are various
+	  issues with the ath9k RC and minstrel is a more robust algorithm.
+	  Note that even if this option is selected, "ath9k_rate_control"
+	  has to be passed to mac80211 using the module parameter,
+	  ieee80211_default_rc_algo.

 config ATH9K_HTC
        tristate "Atheros HTC based wireless cards support"
diff --git a/drivers/net/wireless/ath/ath9k/Makefile b/drivers/net/wireless/ath/ath9k/Makefile
index 3f0b8472..04b51c5 100644
--- a/drivers/net/wireless/ath/ath9k/Makefile
+++ b/drivers/net/wireless/ath/ath9k/Makefile
@@ -6,7 +6,7 @@ ath9k-y +=	beacon.o \
 		xmit.o

 ath9k-$(CONFIG_ATH9K_BTCOEX_SUPPORT) += mci.o
-ath9k-$(CONFIG_ATH9K_RATE_CONTROL) += rc.o
+ath9k-$(CONFIG_ATH9K_LEGACY_RATE_CONTROL) += rc.o
 ath9k-$(CONFIG_ATH9K_PCI) += pci.o
 ath9k-$(CONFIG_ATH9K_AHB) += ahb.o
 ath9k-$(CONFIG_ATH9K_DEBUGFS) += debug.o
diff --git a/drivers/net/wireless/ath/ath9k/init.c b/drivers/net/wireless/ath/ath9k/init.c
index 377846b..9aa005e 100644
--- a/drivers/net/wireless/ath/ath9k/init.c
+++ b/drivers/net/wireless/ath/ath9k/init.c
@@ -720,10 +720,6 @@ void ath9k_set_hw_capab(struct ath_softc *sc, struct ieee80211_hw *hw)
 	sc->ant_rx = hw->wiphy->available_antennas_rx;
 	sc->ant_tx = hw->wiphy->available_antennas_tx;

-#ifdef CONFIG_ATH9K_RATE_CONTROL
-	hw->rate_control_algorithm = "ath9k_rate_control";
-#endif
-
 	if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_2GHZ)
 		hw->wiphy->bands[IEEE80211_BAND_2GHZ] =
 			&sc->sbands[IEEE80211_BAND_2GHZ];
diff --git a/drivers/net/wireless/ath/ath9k/rc.h b/drivers/net/wireless/ath/ath9k/rc.h
index 75f8e9b..12cf122 100644
--- a/drivers/net/wireless/ath/ath9k/rc.h
+++ b/drivers/net/wireless/ath/ath9k/rc.h
@@ -219,7 +219,7 @@ struct ath_rate_priv {
 	struct ath_rc_stats rcstats[RATE_TABLE_SIZE];
 };

-#ifdef CONFIG_ATH9K_RATE_CONTROL
+#ifdef CONFIG_ATH9K_LEGACY_RATE_CONTROL
 int ath_rate_control_register(void);
 void ath_rate_control_unregister(void);
 #else
--
1.8.1.2