Return-path: Received: from nbd.name ([46.4.11.11]:53676 "EHLO nbd.name" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753063Ab1GEDLq (ORCPT ); Mon, 4 Jul 2011 23:11:46 -0400 From: Felix Fietkau To: linux-wireless@vger.kernel.org Cc: linville@tuxdriver.com, ath5k-devel@lists.ath5k.org, mickflemm@gmail.com Subject: [PATCH v2 7/8] ath5k: disable 32KHz sleep clock operation by default Date: Tue, 5 Jul 2011 10:11:23 +0700 Message-Id: <1309835484-26653-7-git-send-email-nbd@openwrt.org> (sfid-20110705_051155_994325_DD085A3F) In-Reply-To: <1309835484-26653-6-git-send-email-nbd@openwrt.org> References: <1309835484-26653-1-git-send-email-nbd@openwrt.org> <1309835484-26653-2-git-send-email-nbd@openwrt.org> <1309835484-26653-3-git-send-email-nbd@openwrt.org> <1309835484-26653-4-git-send-email-nbd@openwrt.org> <1309835484-26653-5-git-send-email-nbd@openwrt.org> <1309835484-26653-6-git-send-email-nbd@openwrt.org> Sender: linux-wireless-owner@vger.kernel.org List-ID: While 32 KHz sleep clock might provide some power saving benefits, it is also a major source of stability issues, on OpenWrt it produced some reproducible data bus errors on register accesses on several different MIPS platforms. All the Atheros drivers that I can find do not enable this feature, so it makes sense to leave it disabled in ath5k as well. Signed-off-by: Felix Fietkau --- drivers/net/wireless/ath/ath5k/ath5k.h | 2 ++ drivers/net/wireless/ath/ath5k/debug.c | 3 +++ drivers/net/wireless/ath/ath5k/reset.c | 11 ++++++++--- 3 files changed, 13 insertions(+), 3 deletions(-) diff --git a/drivers/net/wireless/ath/ath5k/ath5k.h b/drivers/net/wireless/ath/ath5k/ath5k.h index c4c02d5..6ea4d5d 100644 --- a/drivers/net/wireless/ath/ath5k/ath5k.h +++ b/drivers/net/wireless/ath/ath5k/ath5k.h @@ -1066,6 +1066,8 @@ struct ath5k_hw { u8 ah_retry_long; u8 ah_retry_short; + u32 ah_use_32khz_clock; + u8 ah_coverage_class; bool ah_ack_bitrate_high; u8 ah_bwmode; diff --git a/drivers/net/wireless/ath/ath5k/debug.c b/drivers/net/wireless/ath/ath5k/debug.c index 0bf7313..c0cebb7 100644 --- a/drivers/net/wireless/ath/ath5k/debug.c +++ b/drivers/net/wireless/ath/ath5k/debug.c @@ -918,6 +918,9 @@ ath5k_debug_init_device(struct ath5k_softc *sc) debugfs_create_file("queue", S_IWUSR | S_IRUSR, phydir, sc, &fops_queue); + + debugfs_create_bool("32khz_clock", S_IWUSR | S_IRUSR, phydir, + &sc->ah->ah_use_32khz_clock); } /* functions used in other places */ diff --git a/drivers/net/wireless/ath/ath5k/reset.c b/drivers/net/wireless/ath/ath5k/reset.c index efcc4df..d94db31 100644 --- a/drivers/net/wireless/ath/ath5k/reset.c +++ b/drivers/net/wireless/ath/ath5k/reset.c @@ -1287,11 +1287,16 @@ int ath5k_hw_reset(struct ath5k_hw *ah, enum nl80211_iftype op_mode, ath5k_hw_dma_init(ah); - /* Enable 32KHz clock function for AR5212+ chips + /* + * Enable 32KHz clock function for AR5212+ chips * Set clocks to 32KHz operation and use an * external 32KHz crystal when sleeping if one - * exists */ - if (ah->ah_version == AR5K_AR5212 && + * exists. + * Disabled by default because it is also disabled in + * other drivers and it is known to cause stability + * issues on some devices + */ + if (ah->ah_use_32khz_clock && ah->ah_version == AR5K_AR5212 && op_mode != NL80211_IFTYPE_AP) ath5k_hw_set_sleep_clock(ah, true); -- 1.7.3.2