Return-path: Received: from mx1.redhat.com ([209.132.183.28]:18205 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751825Ab3H0IPc (ORCPT ); Tue, 27 Aug 2013 04:15:32 -0400 Date: Tue, 27 Aug 2013 10:13:40 +0200 From: Stanislaw Gruszka To: "John W. Linville" Cc: Fabien ADAM , linux-wireless@vger.kernel.org, users@rt2x00.serialmonkey.com, Paul Menzel , Gertjan van Wingerde Subject: [PATCH 3.11 v2] rt2800: fix wrong TX power compensation Message-ID: <20130827081340.GB2609@redhat.com> (sfid-20130827_101540_717758_DB8248F7) References: <20130826131851.GB10525@redhat.com> <1377548398.4408.4.camel@mattotaupa> <20130827080001.GA2609@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <20130827080001.GA2609@redhat.com> Sender: linux-wireless-owner@vger.kernel.org List-ID: We should not do temperature compensation on devices without EXTERNAL_TX_ALC bit set (called DynamicTxAgcControl on vendor driver). Such devices can have totally bogus TSSI parameters on the EEPROM, but are still treated by us as valid and results in wrong TX power calculations. This fixes inability to connect to AP on slightly longer distance on some Ralink chips/devices without EXTERNAL_TX_ALC configured. Reference: http://thread.gmane.org/gmane.linux.drivers.rt2x00.user/2263 Reported-and-tested-by: Fabien ADAM Cc: stable@vger.kernel.org Signed-off-by: Stanislaw Gruszka Acked-by: Gertjan van Wingerde Acked-by: Paul Menzel --- drivers/net/wireless/rt2x00/rt2800lib.c | 7 +++++++ 1 file changed, 7 insertions(+) v1 -> v2: fix changelog John, If possible this should go to 3.11, -next & cc -stable is also fine as usual. Note that in -next version of the patch rt2x00_eeprom_read() should be changed to rt2800_eeprom_read() do to commit 3e38d3daf881a78ac13e93504a8ac5777040797e diff --git a/drivers/net/wireless/rt2x00/rt2800lib.c b/drivers/net/wireless/rt2x00/rt2800lib.c index 1f80ea5..a0119d3 100644 --- a/drivers/net/wireless/rt2x00/rt2800lib.c +++ b/drivers/net/wireless/rt2x00/rt2800lib.c @@ -2790,6 +2790,13 @@ static int rt2800_get_gain_calibration_delta(struct rt2x00_dev *rt2x00dev) int i; /* + * First check if temperature compensation is supported. + */ + rt2x00_eeprom_read(rt2x00dev, EEPROM_NIC_CONF1, &eeprom); + if (!rt2x00_get_field16(eeprom, EEPROM_NIC_CONF1_EXTERNAL_TX_ALC)) + return 0; + + /* * Read TSSI boundaries for temperature compensation from * the EEPROM. * -- 1.7.11.7