Return-path: Received: from bear.ext.ti.com ([192.94.94.41]:43490 "EHLO bear.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752141Ab2KTPQe (ORCPT ); Tue, 20 Nov 2012 10:16:34 -0500 Message-ID: <50AB9E73.3090802@ti.com> (sfid-20121120_161638_405644_3290EEE0) Date: Tue, 20 Nov 2012 17:14:59 +0200 From: Victor Goldenshtein MIME-Version: 1.0 To: Simon Wunderlich CC: Johannes Berg , , , , , , , , , , , Subject: Re: [PATCH v4 1/6] nl80211/cfg80211: add radar detection command/event References: <1350226137-13704-1-git-send-email-victorg@ti.com> <1350226137-13704-2-git-send-email-victorg@ti.com> <1350414099.10177.13.camel@jlt4.sipsolutions.net> <50842569.5000602@ti.com> <1350910543.10166.3.camel@jlt4.sipsolutions.net> <50922A9D.2060409@ti.com> <1352128887.9466.17.camel@jlt4.sipsolutions.net> <50A26163.10300@ti.com> <20121113180505.GB19223@pandem0nium> In-Reply-To: <20121113180505.GB19223@pandem0nium> Content-Type: text/plain; charset="UTF-8"; format=flowed Sender: linux-wireless-owner@vger.kernel.org List-ID: On 13/11/2012 20:05, Simon Wunderlich wrote: > On Tue, Nov 13, 2012 at 05:04:03PM +0200, Victor Goldenshtein wrote: >> On 05/11/2012 17:21, Johannes Berg wrote: >>> On Thu, 2012-11-01 at 09:54 +0200, Victor Goldenshtein wrote: >>>> On 22/10/2012 14:55, Johannes Berg wrote: >>>>>> 2. In __nl80211_set_channel() - to cover the case when the CAC was >>>>>> initiated on a "preset_chan" (during AP init phase) and the IF was >>>>>> removed before the AP was even started (local->oper_channel wasn't set yet). >>>>> >>>>> Hmm, I'm not sure I get it. How is "local->oper_channel" (a mac80211 >>>>> variable) related to this cfg80211 code? >>>> >>>> It's not, just saying that its not set at this point. >>>> >>>>> start_ap() isn't expected to be able to succeed until CAC passed >>>>> successfully, but OTOH the channel isn't configured until then? >>>> >>>> right, the initial CAC performed before start_ap(), only by setting the >>>> channel with __nl80211_set_channel() + radar detection command. >>> >>> Hmm. Maybe then the channel should be passed to the radar detection >>> command instead? That way, it can be passed through, you can allocate a >>> channel context, etc. Much easier? >> >> We already pass the frequency in the radar detection command, the >> set channel operation comes during hostapd init flow regardless DFS >> implementation. > > Just for clarification for the API: Is the driver required to (re)set the channel > itself in the radar detection command, or do we expect that the channel was already > set via __nl80211_set_channel() (or other means) before? > > This would be important for other DFS modes like IBSS later. > Already discussed this privately, still maybe someone else also interested. The set channel operation is relevant only during initial CAC test, it set and re-set (if necessary - e.g. radar detected on the first channel) by the hostapd it self, so the driver doesn't required to set the channel in the radar detection command. -- Thanks, Victor.