Return-path: Received: from mail-qy0-f174.google.com ([209.85.216.174]:60505 "EHLO mail-qy0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934801Ab1JEW1Y convert rfc822-to-8bit (ORCPT ); Wed, 5 Oct 2011 18:27:24 -0400 Received: by qyk30 with SMTP id 30so4880696qyk.19 for ; Wed, 05 Oct 2011 15:27:24 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <201110041538.12885.chunkeey@googlemail.com> References: <1317637758-11907-1-git-send-email-zefir.kurtisi@neratec.com> <201110032124.53937.chunkeey@googlemail.com> <201110041538.12885.chunkeey@googlemail.com> From: "Luis R. Rodriguez" Date: Wed, 5 Oct 2011 15:27:03 -0700 Message-ID: (sfid-20111006_002728_329083_BE17E580) Subject: Re: [ath9k-devel] [RFC 5/6] ath9k: enable DFS pulse detection To: Christian Lamparter Cc: kgiori@qca.qualcomm.com, ath9k-devel@lists.ath9k.org, linux-wireless@vger.kernel.org, Zefir Kurtisi Content-Type: text/plain; charset=UTF-8 Sender: linux-wireless-owner@vger.kernel.org List-ID: On Tue, Oct 4, 2011 at 6:38 AM, Christian Lamparter wrote: > On Monday, October 03, 2011 09:31:12 PM Luis R. Rodriguez wrote: >> On Mon, Oct 3, 2011 at 12:24 PM, Christian Lamparter >> wrote: >> > On Monday, October 03, 2011 08:27:39 PM Luis R. Rodriguez wrote: >> >> On Mon, Oct 3, 2011 at 3:29 AM, Zefir Kurtisi wrote: >> >> > >> >> > Signed-off-by: Zefir Kurtisi >> >> > --- >> >> >  drivers/net/wireless/ath/ath9k/main.c |   12 ++++++++++++ >> >> >  1 files changed, 12 insertions(+), 0 deletions(-) >> >> > >> >> > diff --git a/drivers/net/wireless/ath/ath9k/main.c b/drivers/net/wireless/ath/ath9k/main.c >> >> > index e8aeb98..5defebe 100644 >> >> > --- a/drivers/net/wireless/ath/ath9k/main.c >> >> > +++ b/drivers/net/wireless/ath/ath9k/main.c >> >> > @@ -344,6 +344,18 @@ static int ath_reset_internal(struct ath_softc *sc, struct ath9k_channel *hchan, >> >> >                        "Unable to reset channel, reset status %d\n", r); >> >> >                goto out; >> >> >        } >> >> > +#ifdef CONFIG_ATH9K_DFS >> >> >> >> Please spare the #ifdef and just call something within dfs.c, then >> >> dfs.h would wrap it to nothing if DFS is disabled. >> > Why would anyone want to disable DFS driver support? >> > I would say: drop the ifdefs altogether since DFS >> > is and will be "required". >> >> Because DFS requires to be properly tested before being enabled. > Testing if a driver detects a pulse is "trivial" compared to the > stuff mac80211/cfg80211 and hostapd will have to do to make a > channel-change as smooth as possible. I think if there's a DFS > "OFF" switch, it should be in hostapd and I hope more people > agree on this one. You do have a good point, but I disagree that you do not need to test / regress test hardware / driver code for DFS. This is what I'm talking about. But yes, userspace also submits itself to the same criteria. >> You may also want to simply disable DFS if you do not want to >> deal with the regulatory test implications of having it enabled. > AFAIK you can't "simply" disable the DFS requirement: hostapd > (hw_features.c), [cfg80211] (checks if tx on secondary channel > is possible) and mac80211 (tx.c) all have checks. Indeed, the > easiest way is to modify crda's database. So there's no need > for an extra compile-time option. No, DFS is set for certain channels on wireless-regdb/CRDA, I just posted DFS master region support for wireless-regdb and CRDA. Apart from this we then need driver support. To get DFS you need all of these + hostapd part. Each one has its own set of components and does deserve its own set of tests and review. Luis