Return-path: Received: from mail-ww0-f44.google.com ([74.125.82.44]:58512 "EHLO mail-ww0-f44.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755367Ab1FWNks convert rfc822-to-8bit (ORCPT ); Thu, 23 Jun 2011 09:40:48 -0400 MIME-Version: 1.0 In-Reply-To: References: Date: Thu, 23 Jun 2011 19:10:46 +0530 Message-ID: (sfid-20110623_154109_301444_09C05688) Subject: Re: [ath9k-devel] Disabling the third antenna for AR9380 in ath9k From: Mohammed Shafi To: Adrian Chadd , Fred Matthews Cc: linux-kernel@vger.kernel.org, linux-wireless@vger.kernel.org, ath9k-devel@venema.h4ckr.net, ath9k-devel@lists.ath9k.org, susinder@qca.qualcomm.com Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-wireless-owner@vger.kernel.org List-ID: On Thu, Jun 23, 2011 at 5:52 PM, Adrian Chadd wrote: > As I said, there's a value in the ath9k code that gets set based on > the chipset type. > > static void setup_ht_cap(struct ath_softc *sc, > ? ? ? ? ? ? ? ? ? ? ? ? struct ieee80211_sta_ht_cap *ht_info) > > in init.c > > That should be all you need to do to communicate to the higher layers > that you only support 2 streams. rather than changing the chain mask via debugfs, the best way is to hard code them when we read the chain mask from EEPROM(with inputs from Susinder) diff --git a/drivers/net/wireless/ath/ath9k/hw.c b/drivers/net/wireless/ath/ath9k/hw.c index 07827b5..b96e380 100644 --- a/drivers/net/wireless/ath/ath9k/hw.c +++ b/drivers/net/wireless/ath/ath9k/hw.c @@ -1990,6 +1990,9 @@ int ath9k_hw_fill_cap_info(struct ath_hw *ah) /* Use rx_chainmask from EEPROM. */ pCap->rx_chainmask = ah->eep_ops->get_eeprom(ah, EEP_RX_MASK); + pCap->tx_chainmask = 0x3; + pCap->rx_chainmask = 0x3; + ah->misc_mode |= AR_PCU_MIC_NEW_LOC_ENA; /* enable key search for every frame in an aggregate */ > > You're checking the wrong place. You're seeing _TX_ errors, but what > you're not seeing (likely because you don't have a 3 stream peer) is > that you're still advertising supporting MCS0->24, so peers may send > you MCS16->24 even though you can't receive it. > > The correct way is to patch the driver to only enable 2 streams in the > HT capability setup, so mac80211 and the rate control code only > advertises MCS0-15 and TX'es MCS0-15 respectively. > > (You have to do this as well as disabling the third chain btw.) > > > > Adrian > > On 23 June 2011 20:16, Mohammed Shafi wrote: >> On Thu, Jun 23, 2011 at 5:26 PM, Fred Matthews wrote: >>> >>> >>> Hi, >>> >>> Regarding streams used in Minstrel RC, I found that in "net/mac80211/rc80211_minstrel_ht.h", at line 16, there is "#define MINSTREL_MAX_STREAMS ?3", that sets the number of streams for minstrel RC. >>> >>> Now can someone help to pass this onto debugfs, so that we can change from 3 streams to 2 streams at runtime like the rx_chainmask. I tried creating a u8 stream_number and struct dentry *dbg_stream_number in the header file, then a debugfs_create_u8 in the c file. Then used it to redefine MINSTREL_MAX_STREAMS, but when I tested this I got errors, therefore, can anyone kindly share a patch to do this correctly. >> >> hi, >> >> i am not familiar with the minstrel rate control, but as you had asked >> I grep'd for MINSTREL_MAX_STREAMS to see if we can quickly add a debug >> entry to change it. but usage like this below suggests we can quickly >> hack the macro to 2 rather than adding a debug entry >> >> const struct mcs_group minstrel_mcs_groups[] = { >> ? ? ? ?MCS_GROUP(1, 0, 0), >> ? ? ? ?MCS_GROUP(2, 0, 0), >> #if MINSTREL_MAX_STREAMS >= 3 >> ? ? ? ?MCS_GROUP(3, 0, 0), >> #endif >> >> >>> >>> Thanks in advance >>> >>> >>> >>> On Wed, Jun 22, 2011 at 3:57 PM, Mohammed Shafi wrote: >>>> On Wed, Jun 22, 2011 at 6:12 PM, Fred Matthews wrote: >>>>> >>>>> Hi, >>>>> >>>>> I used that command to disable the third antenna, and applied it to both AP >>>>> and STA AR9380 NICs. >>>>> I then performed an IPerf test between both and then captured the statistics >>>>> from the sender, (below) . >>>>> You can see that in rc_stats (minstrel), the rate control actually >>>>> "attempts" sending on 3 stream MCSs (16-23) around 256 times each. >>>> >>>> just a guess. as we are changing the chain mask via debugfs and there >>>> may be a chance we may not have informed the minstrel rate control >>>> which is maintained in upper layer(mac80211) and it might be taking >>>> what we have configured the chain masks while we had initialized the >>>> device and i have very little idea about ministrel rate control >>>> >>>>> >>>>> Is there any way to prevent the RC from even attempting those rates, as if I >>>>> where to fully imitate an AR9280, it shouldnt attempt at those MCSs. >>>> >>>> may be we can try with ath9k rate control, and see what happens which >>>> is within the ath9k driver and affects xmit.c and it may have been >>>> informed of the chain mask change. >>>> >>>>> >>>>> Can Susinders comments also be detailed. >>>>> >>>>> Thanks in advance >>>>> >>>>> # cat /sys/kernel/debug/ieee80211/phy0/netdev\:wlan0/stations/00\MAC/ >>>>> >>>>> AUTH >>>>> ASSOC >>>>> AUTHORIZED >>>>> WME >>>>> ht supported >>>>> cap: 0x11ce >>>>> ? ? HT20/HT40 >>>>> ? ? SM Power Save disabled >>>>> ? ? RX HT40 SGI >>>>> ? ? TX STBC >>>>> ? ? RX STBC 1-stream >>>>> ? ? Max AMSDU length: 7935 bytes >>>>> ? ? DSSS/CCK HT40 >>>>> ampdu factor/density: 3/6 >>>>> MCS mask: ff ff ff 00 00 00 00 00 00 00 >>>>> MCS tx params: 1 >>>>> 792 >>>>> 150 ffff ffff ffff ffff ffff 60 ffff ffff ffff ffff ffff ffff ffff ffff ffff >>>>> a40 >>>>> -77 >>>>> 0 >>>>> type ? ? ?rate ? ? throughput ?ewma prob ? this prob ?this succ/attempt >>>>> success ? ?attempts >>>>> HT20/LGI ? ?MCS0 ? ? ? ?6.6 ? ? ? 99.9 ? ? ?100.0 ? ? ? ? ?0( ?0) ? ? ? ?163 >>>>> ? ? ? ? 230 >>>>> HT20/LGI ? ?MCS1 ? ? ? 13.1 ? ? ?100.0 ? ? ?100.0 ? ? ? ? ?0( ?0) ? ? ? ? 75 >>>>> ? ? ? ? ?75 >>>>> HT20/LGI ? ?MCS2 ? ? ? 19.3 ? ? ?100.0 ? ? ?100.0 ? ? ? ? ?0( ?0) ? ? ? ?252 >>>>> ? ? ? ? 252 >>>>> HT20/LGI ? ?MCS3 ? ? ? 25.4 ? ? ?100.0 ? ? ?100.0 ? ? ? ? ?0( ?0) ? ? ? ? 75 >>>>> ? ? ? ? ?75 >>>>> HT20/LGI ? ?MCS4 ? ? ? 36.2 ? ? ? 97.5 ? ? ?100.0 ? ? ? ? ?0( ?0) ? ? ? ?413 >>>>> ? ? ? ? 474 >>>>> HT20/LGI ? ?MCS5 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? ?0 >>>>> ? ? ? ? ?76 >>>>> HT20/LGI ? ?MCS6 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? ?0 >>>>> ? ? ? ? ?80 >>>>> HT20/LGI ? ?MCS7 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? ?0 >>>>> ? ? ? ? 256 >>>>> HT20/LGI ? ?MCS8 ? ? ? 13.1 ? ? ?100.0 ? ? ?100.0 ? ? ? ? ?0( ?0) ? ? ? ? 75 >>>>> ? ? ? ? ?75 >>>>> HT20/LGI ? ?MCS9 ? ? ? 25.4 ? ? ?100.0 ? ? ?100.0 ? ? ? ? ?0( ?0) ? ? ? ? 70 >>>>> ? ? ? ? ?70 >>>>> HT20/LGI ? ?MCS10 ? ? ?34.2 ? ? ? 92.2 ? ? ?100.0 ? ? ? ? ?0( ?0) ? ? ? ? 79 >>>>> ? ? ? ? ?82 >>>>> HT20/LGI ? ?MCS11 ? ? ? 0.0 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? ?0 >>>>> ? ? ? ? ?76 >>>>> HT20/LGI ? ?MCS12 ? ? ? 0.0 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? ?0 >>>>> ? ? ? ? 256 >>>>> HT20/LGI ? ?MCS13 ? ? ? 0.0 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? ?0 >>>>> ? ? ? ? 256 >>>>> HT20/LGI ? ?MCS14 ? ? ? 0.0 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? ?0 >>>>> ? ? ? ? 256 >>>>> HT20/LGI ? ?MCS15 ? ? ? 0.0 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? ?0 >>>>> ? ? ? ? 256 >>>>> HT20/LGI ? ?MCS16 ? ? ? 0.0 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? ?0 >>>>> ? ? ? ? ?75 >>>>> HT20/LGI ? ?MCS17 ? ? ? 0.0 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? ?0 >>>>> ? ? ? ? ?68 >>>>> HT20/LGI ? ?MCS18 ? ? ? 0.0 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? ?0 >>>>> ? ? ? ? ?85 >>>>> HT20/LGI ? ?MCS19 ? ? ? 0.0 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? ?0 >>>>> ? ? ? ? 257 >>>>> HT20/LGI ? ?MCS20 ? ? ? 0.0 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? ?0 >>>>> ? ? ? ? 256 >>>>> HT20/LGI ? ?MCS21 ? ? ? 0.0 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? ?0 >>>>> ? ? ? ? 256 >>>>> HT20/LGI ? ?MCS22 ? ? ? 0.0 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? ?0 >>>>> ? ? ? ? 256 >>>>> HT20/LGI ? ?MCS23 ? ? ? 0.0 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? ?0 >>>>> ? ? ? ? 256 >>>>> HT40/LGI ? ?MCS0 ? ? ? 13.6 ? ? ?100.0 ? ? ?100.0 ? ? ? ? ?0( ?0) ? ? ? ? 75 >>>>> ? ? ? ? ?75 >>>>> HT40/LGI ? ?MCS1 ? ? ? 26.5 ? ? ?100.0 ? ? ?100.0 ? ? ? ? ?0( ?0) ? ? ? ? 72 >>>>> ? ? ? ? ?72 >>>>> HT40/LGI ? ?MCS2 ? ? ? 38.3 ? ? ?100.0 ? ? ?100.0 ? ? ? ? ?0( ?0) ? ? ? ? 73 >>>>> ? ? ? ? ?73 >>>>> HT40/LGI ? ?MCS3 ? ? ? 49.7 ? ? ? 99.9 ? ? ?100.0 ? ? ? ? ?0( ?0) ? ? ? ? 70 >>>>> ? ? ? ? ?73 >>>>> HT40/LGI ? ?MCS4 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? 10 >>>>> ? ? ? ?1220 >>>>> HT40/LGI ? ?MCS5 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? ?0 >>>>> ? ? ? ? 256 >>>>> HT40/LGI ? ?MCS6 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? ?0 >>>>> ? ? ? ? 256 >>>>> HT40/LGI ? ?MCS7 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? ?0 >>>>> ? ? ? ? 256 >>>>> HT40/LGI ? ?MCS8 ? ? ? 26.2 ? ? ? 98.9 ? ? ?100.0 ? ? ? ? ?0( ?0) ? ? ? ? 73 >>>>> ? ? ? ? ?74 >>>>> HT40/LGI ? ?MCS9 ? ? ? 49.3 ? ? ? 99.2 ? ? ?100.0 ? ? ? ? ?0( ?0) ? ? ? ? 67 >>>>> ? ? ? ? ?69 >>>>> HT40/LGI ? ?MCS10 ? ? ?20.5 ? ? ? 28.9 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? 14 >>>>> ? ? ? ? 255 >>>>> HT40/LGI ? ?MCS11 ? ? ? 0.0 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? ?0 >>>>> ? ? ? ? 257 >>>>> HT40/LGI ? ?MCS12 ? ? ? 0.0 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? ?0 >>>>> ? ? ? ? 256 >>>>> HT40/LGI ? ?MCS13 ? ? ? 0.0 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? ?0 >>>>> ? ? ? ? 256 >>>>> HT40/LGI ? ?MCS14 ? ? ? 0.0 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? ?0 >>>>> ? ? ? ? 256 >>>>> HT40/LGI ? ?MCS15 ? ? ? 0.0 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? ?0 >>>>> ? ? ? ? 256 >>>>> HT40/LGI ? ?MCS16 ? ? ? 0.0 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? ?0 >>>>> ? ? ? ? ?74 >>>>> HT40/LGI ? ?MCS17 ? ? ? 0.0 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? ?0 >>>>> ? ? ? ? 256 >>>>> HT40/LGI ? ?MCS18 ? ? ? 0.0 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? ?0 >>>>> ? ? ? ? 255 >>>>> HT40/LGI ? ?MCS19 ? ? ? 0.0 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? ?0 >>>>> ? ? ? ? 256 >>>>> HT40/LGI ? ?MCS20 ? ? ? 0.0 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? ?0 >>>>> ? ? ? ? 256 >>>>> HT40/LGI ? ?MCS21 ? ? ? 0.0 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? ?0 >>>>> ? ? ? ? 256 >>>>> HT40/LGI ? ?MCS22 ? ? ? 0.0 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? ?0 >>>>> ? ? ? ? 256 >>>>> HT40/LGI ? ?MCS23 ? ? ? 0.0 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? ?0 >>>>> ? ? ? ? 256 >>>>> HT40/SGI ? ?MCS0 ? ? ? 15.1 ? ? ?100.0 ? ? ?100.0 ? ? ? ? ?0( ?0) ? ? ? ? 70 >>>>> ? ? ? ? ?70 >>>>> HT40/SGI ? ?MCS1 ? ? ? 29.2 ? ? ?100.0 ? ? ?100.0 ? ? ? ? ?0( ?0) ? ? ? ? 72 >>>>> ? ? ? ? ?72 >>>>> HT40/SGI ?t MCS2 ? ? ? 38.5 ? ? ? 91.3 ? ? ?100.0 ? ? ? ? ?0( ?0) ? ? ? ? 81 >>>>> ? ? ? ? ?83 >>>>> HT40/SGI ? PMCS3 ? ? ? 54.3 ? ? ? 99.5 ? ? ?100.0 ? ? ? ? ?0( ?0) ? ? ?66536 >>>>> ? ? ? 67803 >>>>> HT40/SGI ? ?MCS4 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? ?0 >>>>> ? ? ? ? 256 >>>>> HT40/SGI ? ?MCS5 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? ?0 >>>>> ? ? ? ? 256 >>>>> HT40/SGI ? ?MCS6 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? ?0 >>>>> ? ? ? ? 256 >>>>> HT40/SGI ? ?MCS7 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? ?0 >>>>> ? ? ? ? 256 >>>>> HT40/SGI ? ?MCS8 ? ? ? 29.2 ? ? ?100.0 ? ? ?100.0 ? ? ? ? ?0( ?0) ? ? ? ? 67 >>>>> ? ? ? ? ?67 >>>>> HT40/SGI T ?MCS9 ? ? ? 54.6 ? ? ? 99.9 ? ? ?100.0 ? ? ? ? ?0( ?0) ? ? 310227 >>>>> ? ? ?312339 >>>>> HT40/SGI ? ?MCS10 ? ? ?22.7 ? ? ? 29.3 ? ? ?100.0 ? ? ? ? ?0( ?0) ? ? ? ? 14 >>>>> ? ? 46.8 Mbits/sec ? ?255 >>>>> HT40/SGI ? ?MCS11 ? ? ? 0.0 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? ?0 >>>>> ? ? ? ? 256 >>>>> HT40/SGI ? ?MCS12 ? ? ? 0.0 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? ?0 >>>>> ? ? ? ? 255 >>>>> HT40/SGI ? ?MCS13 ? ? ? 0.0 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? ?0 >>>>> ? ? ? ? 256 >>>>> HT40/SGI ? ?MCS14 ? ? ? 0.0 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? ?0 >>>>> ? ? ? ? 256 >>>>> HT40/SGI ? ?MCS15 ? ? ? 0.0 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? ?0 >>>>> ? ? ? ? 256 >>>>> HT40/SGI ? ?MCS16 ? ? ? 0.0 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? ?0 >>>>> ? ? ? ? ?68 >>>>> HT40/SGI ? ?MCS17 ? ? ? 0.0 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? ?0 >>>>> ? ? ? ? 256 >>>>> HT40/SGI ? ?MCS18 ? ? ? 0.0 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? ?0 >>>>> ? ? ? ? 255 >>>>> HT40/SGI ? ?MCS19 ? ? ? 0.0 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? ?0 >>>>> ? ? ? ? 256 >>>>> HT40/SGI ? ?MCS20 ? ? ? 0.0 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? ?0 >>>>> ? ? ? ? 256 >>>>> HT40/SGI ? ?MCS21 ? ? ? 0.0 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? ?0 >>>>> ? ? ? ? 256 >>>>> HT40/SGI ? ?MCS22 ? ? ? 0.0 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? ?0 >>>>> ? ? ? ? 256 >>>>> HT40/SGI ? ?MCS23 ? ? ? 0.0 ? ? ? ?0.0 ? ? ? ?0.0 ? ? ? ? ?0( ?0) ? ? ? ? ?0 >>>>> ? ? ? ? 256 >>>>> >>>>> Total packet count:: ? ?ideal 365056 ? ? ?lookaround 13702 >>>>> Average A-MPDU length: 5.4 >>>>> >>>>>> Date: Tue, 21 Jun 2011 14:25:36 +0530 >>>>>> Subject: Re: [ath9k-devel] Disabling the third antenna for AR9380 in ath9k >>>>>> From: shafi.wireless@gmail.com >>>>>> To: fredmm@hotmail.co.uk >>>>>> CC: linux-kernel@vger.kernel.org; linux-wireless@vger.kernel.org; >>>>>> ath9k-devel@venema.h4ckr.net; ath9k-devel@lists.ath9k.org; >>>>>> susinder@qca.qualcomm.com >>>>>> >>>>>> On Tue, Jun 21, 2011 at 2:07 AM, Fred Matthews >>>>>> wrote: >>>>>> > Hi all, >>>>>> > I am installing the AR9380 NIC on laptops, but some only have two UFL >>>>>> > connectors, and thus I was wondering if using only two of the UFL >>>>>> > antenna >>>>>> > ports will have any negative effect or difference than installing a 2x2 >>>>>> > NIC >>>>>> > (AR9280 for example which has only 2 ports anyway). Please kindly >>>>>> > explain >>>>>> > with references if possible. >>>>>> > Also for example is there anyway to disable transmission on the third >>>>>> > UFL >>>>>> > port (antenna) from ath9k or otherwise. >>>>>> > Thank you all very much >>>>>> >>>>>> you can change the tx/rx chainmask for 3x3 AR9380 to disable >>>>>> transmission on the third antenna >>>>>> cd /sys/kernel/debug/ieee80211/phy0/ath9k# echo 0x3 > tx_chainmask >>>>>> cd /sys/kernel/debug/ieee80211/phy0/ath9k# echo 0x3 > rx_chainmask >>>>>> >>>>>> after this, ideally it should operate as 2x2 device as per Susinders >>>>>> comments. but if you got AR9280 please try to use that if 2 antenna is >>>>>> the constraint. >>>>>> >>>>>> >>>>>> > _______________________________________________ >>>>>> > ath9k-devel mailing list >>>>>> > ath9k-devel@lists.ath9k.org >>>>>> > https://lists.ath9k.org/mailman/listinfo/ath9k-devel >>>>>> > >>>>>> > >>>>>> >>>>>> >>>>>> >>>>>> -- >>> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?-- >>> To unsubscribe from this list: send the line "unsubscribe linux-wireless" in >>> the body of a message to majordomo@vger.kernel.org >>> More majordomo info at ?http://vger.kernel.org/majordomo-info.html >>> >> >> >> >> -- >> shafi >> > -- shafi