Return-path: Received: from mail-gw3-out.broadcom.com ([216.31.210.64]:23230 "EHLO mail-gw3-out.broadcom.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751894AbbLBNc7 (ORCPT ); Wed, 2 Dec 2015 08:32:59 -0500 Message-ID: <565EF307.90002@broadcom.com> (sfid-20151202_143304_117052_53D8F3D9) Date: Wed, 2 Dec 2015 14:32:55 +0100 From: Arend van Spriel MIME-Version: 1.0 To: Jouni Malinen , Kalle Valo CC: linux-wireless , Hante Meuleman , Dan Williams Subject: Re: [PATCH 08/11] brcmfmac: Make 5G join preference configurable. References: <1448447567-12189-1-git-send-email-arend@broadcom.com> <1448447567-12189-9-git-send-email-arend@broadcom.com> <87si3nkb2l.fsf@kamboji.qca.qualcomm.com> <565D5B77.7050501@broadcom.com> <87d1uqijnz.fsf@kamboji.qca.qualcomm.com> <20151201110827.GA4362@w1.fi> In-Reply-To: <20151201110827.GA4362@w1.fi> Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Sender: linux-wireless-owner@vger.kernel.org List-ID: On 12/01/2015 12:08 PM, Jouni Malinen wrote: > On Tue, Dec 01, 2015 at 11:48:32AM +0200, Kalle Valo wrote: >> Arend van Spriel writes: >>> It solves a problem for us, but admittedly it is not something that is >>> very usable by user-space apps. So I guess what you are suggesting >>> here is to come up with a nl80211 api for this. On the mailing list >>> (or hostap list) the topic pops up from time to time so there are >>> people who would like to have such a knob to play with. Still would >>> like to keep the module parameter although its use may change when >>> nl80211 api is added. >> >> I don't know what is the best approach, that's why I would like to hear >> opinions from others. Personally I don't like the idea of adding 802.11 >> level configuration options to module parameters, but on the other hand >> I don't have any strong opinions about this. > > I would like to see this as a new attribute to NL80211_CMD_CONNECT to > provide parameters for offloaded (driver and/or firmware) BSS selection > and roaming. If there is a driver that uses roaming offload with > NL80211_CMD_ASSOCIATE, the same attribute could be used there (but I'm > not sure how exact such offloading would work in practice since I'd > expect both authentication and (re)association to be offloaded). Sounds reasonable. Just would like to explore the use-case a bit more. Looking at tools like NetworkManager and android network list, the user is always presented with just SSID listed once. For NetworkManager details can be configured for a connection and the bss selection parameters could be one of those. What level of detail would be needed there. Not saying we can not have more detail in the nl80211 API. >> I guess we have two different designs, one where the roaming logic is in >> firmware and other where wpasupplicant is responsible for this. (And I >> assume that brcfmac belongs to the former group.) Ideally it would be >> nice that we would have a same configuration knob for both but I don't >> know if that's really feasible. > > Both of these would work as long as wpa_supplicant has means for > providing such configuration to the driver in a generic manner. That > NL80211_CMD_CONNECT extension with a new optional attribute would be > such a generic design. So does the driver need to advertise support for bss selection parameters or can it simply ignore the parameters. Assuming the latter for now. Regards, Arend