Return-path: Received: from mail-oi0-f42.google.com ([209.85.218.42]:36419 "EHLO mail-oi0-f42.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752173AbeGDPdo (ORCPT ); Wed, 4 Jul 2018 11:33:44 -0400 Received: by mail-oi0-f42.google.com with SMTP id r16-v6so11458623oie.3 for ; Wed, 04 Jul 2018 08:33:43 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <7e95bd6a-97bc-b030-26ce-83da66e5f279@lwfinger.net> References: <20180704140933.3dk2ylbntltz6jqd@mwanda> <7e95bd6a-97bc-b030-26ce-83da66e5f279@lwfinger.net> From: Daniel Drake Date: Wed, 4 Jul 2018 10:33:42 -0500 Message-ID: (sfid-20180704_173407_430633_0C6F7C99) Subject: Re: [BUG] staging: r8822be: RTL8822be can't find any wireless AP To: Larry Finger Cc: Dan Carpenter , Jian-Hong Pan , Greg Kroah-Hartman , "Frank A. Cancio Bello" , Stanislaw Gruszka , devel@driverdev.osuosl.org, Kalle Valo , linux-wireless , Linux Kernel , Linux Upstreaming Team , Colin Ian King , Ping-Ke Shih , Arnd Bergmann , yhchuang@realtek.com, birming@realtek.com, "shaofu@realtek.com >> shaofu" , steventing@realtek.com Content-Type: text/plain; charset="UTF-8" Sender: linux-wireless-owner@vger.kernel.org List-ID: On Wed, Jul 4, 2018 at 10:13 AM, Larry Finger wrote: > We will have to agree to disagree. > > I have no idea what the vendors are doing that cause some motherboards to > need a different aspm value. What I do know is that we have had to live with > the idiocy of some vendors saving a few pennies by only including a single > antenna, rather than two, and then making a problem by miscoding the EFUSE > bit that indicates which connector is actually in use. As we have no means > that I know about to detect which boxes have the problem, a module parameter > was created, just as in this case. > > I agree that drivers should work "out of the box", but finite resources and > lack of vendor cooperation make this a goal that may not be attainable. As you touched on, the ideal situation is that Realtek solve the issue. Ping-Ke Shih is on CC and I am adding a few more contacts from the commit log. The context is that the r8822 driver fails on several platforms unless setting aspm=0 (the default is 1). https://gist.github.com/dsd/20c05f0c6d66ee2ef9bfbb17f93f18ba https://bugzilla.kernel.org/show_bug.cgi?id=199651 If we don't get a timely fix from Realtek though, I think there is a key difference between the antenna selection headache and this one. In the antenna case, there isn't a good value that you can set that will work on all systems. If you change the default behaviour you will solve the issue for some users while simultanously introducing the problem on other systems that were previously fine. However in this case, it's highly likely that setting aspm=0 (off) by default would work for everyone. It has the disadvantage of using a bit more power, but especially with the indications that this issue affects a significant number of systems, I think that having the driver working out of the box everywhere is more important. The module parameter can be left in place so that unaffected users that want to save power can set aspm=1. Daniel