Return-path: Received: from mail-wg0-f47.google.com ([74.125.82.47]:46965 "EHLO mail-wg0-f47.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1161515Ab3DEIRZ (ORCPT ); Fri, 5 Apr 2013 04:17:25 -0400 Received: by mail-wg0-f47.google.com with SMTP id y10so3411217wgg.26 for ; Fri, 05 Apr 2013 01:17:24 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <1365148844.61162.YahooMailNeo@web193503.mail.sg3.yahoo.com> References: <515A0847.7000306@gmail.com> <1365088789.89181.YahooMailNeo@web193504.mail.sg3.yahoo.com> <1365131280.68622.YahooMailNeo@web193506.mail.sg3.yahoo.com> <1365148844.61162.YahooMailNeo@web193503.mail.sg3.yahoo.com> Date: Fri, 5 Apr 2013 01:17:23 -0700 Message-ID: (sfid-20130405_101733_034732_45415949) Subject: Re: AR9287 ; 2-wire coexistence expected behavior From: Adrian Chadd To: sandeep suresh Cc: "linux-wireless@vger.kernel.org" , ath9k-devel Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-wireless-owner@vger.kernel.org List-ID: There's nothing public, no. Just the source code. :) adrian On 5 April 2013 01:00, sandeep suresh wrote: > Thanks Mr. Adrian. I will revert back to you after sometime. But are there > any documents/datasheets explaining on the BTCOEX mode registers, timing > diagrams for 2-wire/3-wire coexistence based on Atheros chipset? > I have already gone through the ath9k website; but does not contain these > details. > Thanks & Regards > Sandeep. > > From: Adrian Chadd > To: sandeep suresh > Cc: "linux-wireless@vger.kernel.org" ; > ath9k-devel > Sent: Friday, 5 April 2013 9:43 AM > > Subject: Re: AR9287 ; 2-wire coexistence expected behavior > > You'll have to give me some more time to digest what I'm reading > internally; it's all new to me. > > For FreeBSD, you can look at these files in FreeBSD-HEAD: > > sys/dev/ath/ath_hal/ar5416/ar5416_btcoex.c > sys/dev/ath/ath_hal/ar9002/ar9285_btcoex.c (not that relevant for you, > but still) > > These contain the register writes that the internal reference HAL is > doing when programming btcoex for AR9285/AR9287. > > The AR9287 should support 2-wire coex fine. > > Just read those source files. The ar5416InitBTCoex() programs the > BT_ACTIVE / WLAN_ACTIVE gpio's when you say the coexistence type is > 2-wire. There's weights and such being programmed elsewhere; you need > to make sure you pick the default values for that and try it out. > > I can't help you more than that at the moment; I'm busy doing other > work that doesn't at all touch wifi. :) > > > > Adrian > > On 4 April 2013 20:08, sandeep suresh wrote: >> Hello Mr.Adrian, >> Thanks for your mail. Regarding your comment below: >> >> "THen you need to ensure the bluetooth coexistence registers are >> programmed >> so that btactive will correctly stomp wifi traffic." >> >> Can you please elaborate on this? As I understand the concept of >> "stomping" >> is only in 3-wire coexistence; correct me if I am wrong. >> >> As mentioned earlier, the set-up we have is a PCB board with general >> purpose >> MCU controlling the 2-wire coexistence pins of AR9287. As there are other >> 2.4GHz radio (called PROP radio here) on the board, we want to ensure that >> both radios do not transmit at the same time which will result in >> collisions. Hence we want to build a co-operative coexistence approach so >> that when PROP radio is active (by asserting BT_ACTIVE), AR9287 has to >> buffer transmissions and allow PROP radio to be active. Only when PROP >> radio >> is inactive (BT_ACTIVE is deasserted), only then WiFi can be active. Hope >> this is achievable? >> >> Thanks & Regards >> Sandeep. >> >> From: Adrian Chadd >> To: sandeep suresh >> Cc: "linux-wireless@vger.kernel.org" ; >> ath9k-devel >> Sent: Thursday, 4 April 2013 11:36 PM >> >> Subject: Re: AR9287 ; 2-wire coexistence expected behavior >> >> Hi! >> >> I'm glad you're looking into this in more depth! >> >> On 4 April 2013 08:19, sandeep suresh wrote: >> >>> I understand that ATH_BTCOEX_CFG_2_WIRE, ATH_BTACTIVE_GPIO_9280 (GPIO6 as >>> per btcoex.h) and ATH_WLANACTIVE_GPIO_9280 (GPIO5 as per btcoex.h) are >>> used. >> >> Ok, right. >> >>> I next started monitoring GPIO5 on oscillaoscope to see WLAN activity and >>> I >>> could see a lot of pulse trains. Next in order to simulate high priority >>> BT >>> traffic, I pulled the line GPIO6 high. But I did not see any change in >>> WLAN >>> activity as I could continue to see the pulse trains. My expectation was >>> that there should not be any WLAN activity and hence no pulses. Please >>> guide >>> if I am missing anything? >> >> Well, firstyl you need to ensure that the GPIO pin has been programmed >> to be an input, and it's of the right bluetooth type. As I said >> before, GPIO pins can be input, output; they can be connected via an >> internal mux to a variety of "behaviours". Take a look at the gpio >> configure code in ath9k to see more. >> >> THen you need to ensure the bluetooth coexistence registers are >> programmed so that btactive will correctly stomp wifi traffic. >> >> THat's all I know for now. Sorry. >> >> >> >> adrian >> >> > >