Return-path: Received: from mail-ee0-f47.google.com ([74.125.83.47]:59546 "EHLO mail-ee0-f47.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932582Ab3FEVfi (ORCPT ); Wed, 5 Jun 2013 17:35:38 -0400 Received: by mail-ee0-f47.google.com with SMTP id e49so674374eek.6 for ; Wed, 05 Jun 2013 14:35:37 -0700 (PDT) From: Christian Lamparter To: "C.B. Wang" Subject: Re: carl9170:5/10 MHz Channel Support on carl9170 Date: Wed, 5 Jun 2013 23:35:25 +0200 Cc: Adrian Chadd , linux-wireless@vger.kernel.org References: In-Reply-To: MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Message-Id: <201306052335.25953.chunkeey@googlemail.com> (sfid-20130605_235548_587944_5B1F2F77) Sender: linux-wireless-owner@vger.kernel.org List-ID: Hello Adrian On Wednesday, June 05, 2013 08:08:14 PM Adrian Chadd wrote: > I think that the zydas mac doesn't officially support 5/10mhz operation. Just checked, it looks like the bandwidth control is very similar to ath9k. The settings is controlled by Bit 3 and 2 in AR9170_PWR_REG_CLOCK_SEL (0x1d4008) 00 <-- default 01 <-- half There's a new firmware branch for this new feature: The patch for the carl9170 driver will come later... Once mac/nl/cfg80211 and userspace have support for the 5/10 MHz channel bandwidth. So, if you [(Mr.?) Wang] is interested, please help us testing and integrating the stack patchset into the kernel - NOW -: "Add support for 5 and 10 MHz channels" > > I've read the "otus" vendor driver and found that in the source file > > /HalPlus/OTUS_FB50/hpreg.h on > > line 1915,the comment says "Temporary discard channel that BW < 20MHz > > (5 or 10MHz) */ > > /* Our architecture does not implemnt it" > > I think either the driver does not implement the 5/10 channels or > > worse,the ar9170 chip does not support 5/10 mhz channel at all. I think "architecture" could be just the software. At least an ath9k spectral analyzer confirmed that at least the PHY can operate on 10 MHz channels in the 5GHz band. > > But 802.11j has 10mhz channel support.To comply with the 802.11j > > standard,the chip should support 10mhz channel width. Oh, I don't have a 802.11j copy handy, is it a mandatory or optional feature? > > Also the ar9170 MAC was indeed designed by ZyDaS berfore > > the company was taken over by Atheros. Do you know any 5 GHz solution from ZyDaS that sold as 802.11j compliant? > > It has some problems with long distance links. True, but again look at the vendor driver. I think it should be very easy to implement "set coverage class". The slot time can be set by "AR9170_MAC_REG_SLOT_TIME" register and the ack timeout should be in "AR9170_MAC_REG_ACK_EXTENSION". That's all the information I have. So what are you waiting for ;) Regards, Chr