From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail2.candelatech.com ([208.74.158.173]:56748 "EHLO mail2.candelatech.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751922AbbCKVFX (ORCPT ); Wed, 11 Mar 2015 17:05:23 -0400 Message-ID: <5500AE12.6040103@candelatech.com> (sfid-20150311_220526_704884_B7ADAA35) Date: Wed, 11 Mar 2015 14:05:22 -0700 From: Ben Greear MIME-Version: 1.0 To: Johannes Berg CC: linux-wireless@vger.kernel.org Subject: Re: [RFC] mac80211_hwsim: notify user-space about channel change. 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> In-Reply-To: <1424788834.2192.34.camel@sipsolutions.net> Content-Type: text/plain; charset=UTF-8 Sender: linux-wireless-owner@vger.kernel.org List-ID: On 02/24/2015 06:40 AM, Johannes Berg wrote: > On Tue, 2015-02-24 at 06:36 -0800, Ben Greear wrote: > >> We could push more and more of this to user-space and let it decide whether and >> how to forward or accept frames for particular radios. > > Sure, no objection to that. However, just arbitrarily adding a "change > channel" call, without thinking about the realities of the code already > supporting multi-channel concurrency, remain-on-channel and hw-scan > operations won't get us very far and just lead to issues with the API. 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? I would assume that off-channel work could do similar logic. Is that the sort of thing you had in mind? Thanks, Ben >> But, to do that, we need the low-level settings sent to user-space >> (such as current channel). Encryption keys could be a future enhancement >> here, so that we can do 'hardware' encryption in hwsim (and handle encrypt/decrypt >> logic however we want in user-space). > > Sure. I'd just like to ask that the API is actually useful in more than > the default single-channel support BSS-only case :) > > johannes > -- Ben Greear Candela Technologies Inc http://www.candelatech.com