From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from s3.sipsolutions.net ([5.9.151.49]:53151 "EHLO sipsolutions.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751289AbbCaO1y (ORCPT ); Tue, 31 Mar 2015 10:27:54 -0400 Message-ID: <1427812067.2057.27.camel@sipsolutions.net> (sfid-20150331_162758_327425_7F26E55C) Subject: Re: [RFC] mac80211_hwsim: notify user-space about channel change. From: Johannes Berg To: Ben Greear Cc: linux-wireless@vger.kernel.org Date: Tue, 31 Mar 2015 16:27:47 +0200 In-Reply-To: <5500AE12.6040103@candelatech.com> References: <1424217588-29558-1-git-send-email-greearb@candelatech.com> (sfid-20150218_005956_617537_D2A9B91F) <1424692155.2782.6.camel@sipsolutions.net> <54EB66CC.1030800@candelatech.com> <1424772714.2192.16.camel@sipsolutions.net> <54EC8C5D.5090400@candelatech.com> <1424788834.2192.34.camel@sipsolutions.net> <5500AE12.6040103@candelatech.com> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Sender: linux-wireless-owner@vger.kernel.org List-ID: On Wed, 2015-03-11 at 14:05 -0700, Ben Greear wrote: > I took a look at the hw-scan code a bit...I guess we might could do additional > info calls to user-space as we iterate through the channels while scanning? > > A real driver would be causing the NIC to change channels at these junctures, > either by directly setting registers or sending some message off to the > target NIC's cpu, right? Well, depends. Our driver just asks the firmware to do the scan, and it will do all the scheduling by itself, i.e. it'll go through the channels at convenient times etc. > I would assume that off-channel work could do similar logic. Yeah. > Is that the sort of thing you had in mind? To be honest, I'm not really sure myself. It seems to really do this you'd also need powersave handling (tell the AP you're going to sleep when scanning) and potentially P2P-GO NoA handling (tell the clients you're going to sleep). The thing with hwsim right now is that it totally makes use of its ability to be on as many channels at the same time as it wants, so it doesn't have to worry about that, but if you want to actually have the channel "changed" then we need to handle a lot more details. johannes