Return-path: Received: from smtp.codeaurora.org ([198.145.29.96]:44548 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750726AbeCOJAX (ORCPT ); Thu, 15 Mar 2018 05:00:23 -0400 From: Kalle Valo To: Amitkumar Karwar Cc: linux-wireless , Amitkumar Karwar , Siva Rebbagondla , Prameela Rani Garnepudi Subject: Re: [PATCH 01/10] rsi: add support for hardware scan offload References: <1520260620-4694-1-git-send-email-amitkarwar@gmail.com> <1520260620-4694-2-git-send-email-amitkarwar@gmail.com> <87ina00zwv.fsf@purkki.adurom.net> Date: Thu, 15 Mar 2018 11:00:17 +0200 In-Reply-To: (Amitkumar Karwar's message of "Thu, 15 Mar 2018 12:38:08 +0530") Message-ID: <871sgl90im.fsf@kamboji.qca.qualcomm.com> (sfid-20180315_100027_511766_27701EA3) MIME-Version: 1.0 Content-Type: text/plain Sender: linux-wireless-owner@vger.kernel.org List-ID: Amitkumar Karwar writes: > On Tue, Mar 13, 2018 at 8:46 PM, Kalle Valo wrote: >> Amitkumar Karwar writes: >> >>> From: Prameela Rani Garnepudi >>> >>> With the current approach of scanning, roaming delays >>> are observed. Firmware has support for back ground scanning. >>> To get this advantage, mac80211 hardware scan is implemented. >>> In this method, foreground scan is performed in driver and >>> back ground scan is configured to firmware. >> >> To me doesn't like a good idea to duplicate scan functionality in the >> driver. > > There is a limitation with our device. We need to configure background > scan parameters to firmware when device is connected. Yeah, I guessed that. > In non-connected state, we can directly dump probe requests received > from mac80211 as a part of software scan. Some synchronization issues > are with existing software scan when device is connected. This patch > implements hw_scan where these issues are no seen, as driver has more > control on scan state machine What I don't like here is that you are duplicating functionality already existing in mac80211 and I hope there is a better way to solve the problem. Just as a a crazy idea what if the driver returns -EOPNOTSUPP when hardware scan is not possible and mac80211 falls back to software scan? But of course this depends on what Johannes thinks. -- Kalle Valo