[3.19.y-ckt stable] Patch "ath9k: fix DMA stop sequence for AR9003+" has been added to staging queue

[Kamal Mostafa]

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

    ath9k: fix DMA stop sequence for AR9003+

to the linux-3.19.y-queue branch of the 3.19.y-ckt extended stable tree 
which can be found at:

    http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.19.y-queue

This patch is scheduled to be released in version 3.19.y-ckt4.

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

For more information about the 3.19.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

------

>From 3f8922fe3a49ae8456fc1fa437f1b91fb0f6fc94 Mon Sep 17 00:00:00 2001
From: Felix Fietkau <nbd at openwrt.org>
Date: Tue, 2 Jun 2015 10:38:32 +0200
Subject: ath9k: fix DMA stop sequence for AR9003+

commit 300f77c08ded96d33f492aaa02549103852f0c12 upstream.

AR93xx and newer needs to stop rx before tx to avoid getting the DMA
engine or MAC into a stuck state.
This should reduce/fix the occurence of "Failed to stop Tx DMA" logspam.

Signed-off-by: Felix Fietkau <nbd at openwrt.org>
Signed-off-by: Kalle Valo <kvalo at codeaurora.org>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 drivers/net/wireless/ath/ath9k/main.c | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/drivers/net/wireless/ath/ath9k/main.c b/drivers/net/wireless/ath/ath9k/main.c
index 62b0bf4..cea94dbf 100644
--- a/drivers/net/wireless/ath/ath9k/main.c
+++ b/drivers/net/wireless/ath/ath9k/main.c
@@ -216,11 +216,13 @@ static bool ath_prepare_reset(struct ath_softc *sc)
 	ath_stop_ani(sc);
 	ath9k_hw_disable_interrupts(ah);

-	if (!ath_drain_all_txq(sc))
-		ret = false;
-
-	if (!ath_stoprecv(sc))
-		ret = false;
+	if (AR_SREV_9300_20_OR_LATER(ah)) {
+		ret &= ath_stoprecv(sc);
+		ret &= ath_drain_all_txq(sc);
+	} else {
+		ret &= ath_drain_all_txq(sc);
+		ret &= ath_stoprecv(sc);
+	}

 	return ret;
 }
--
1.9.1