From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 97C17C43215 for ; Thu, 28 Nov 2019 16:50:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6C00121787 for ; Thu, 28 Nov 2019 16:50:34 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="oCI2+ouw" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727209AbfK1Quc (ORCPT ); Thu, 28 Nov 2019 11:50:32 -0500 Received: from mail-wm1-f67.google.com ([209.85.128.67]:39988 "EHLO mail-wm1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727113AbfK1Qub (ORCPT ); Thu, 28 Nov 2019 11:50:31 -0500 Received: by mail-wm1-f67.google.com with SMTP id y5so12349469wmi.5; Thu, 28 Nov 2019 08:50:29 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=WUkl5jnRGfV/kV8cyt6Eg+72AaYhmkjbi+1i7ecJ1mo=; b=oCI2+ouwC6FFFtwC3HQe79/vZiJy/YQyFyQwhwV/ymbxp3MvaqFahpwedaEfj3OrdD CuftaRGF0xFpDINRHILhK+cH1tHhFQHfcomOVj8tA9J+v1PZQlceN9zKnUFwempR5po/ akAoN1D9mpSJsG1+QmiNFMAzdOecVbRvq3CM50/jSHNn9DfEw04pDNiR+nchVHhsAHcY ogdXmFfca6ppxNYpCccsY4/OUm+QH8iC2PMyTrKXBFhN3dwTbkC9cwbu6HY3V2iWfUHy kBoKPAJfNNgiFhHGAmb20bV0eCdmC4qimpNUVfsGWM68GiK0LndjbjxsMYd1hNfcDN5U AZrQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=WUkl5jnRGfV/kV8cyt6Eg+72AaYhmkjbi+1i7ecJ1mo=; b=SutU9PjNvgQKASs4XuIHXuKD/tUo4ybyBWar0NF7QuaqAjKTv9NJd3PYwnPoR/7CDK kr3f8WTxwEZvWyCE8diqvWNl8StU5XO6nE8zXRb4uGdebXbqb1GMWagJ9sRNVlYTl6a2 +KOXgAkS6D/KG0GYjBxAWNlUCIS8l/Iu+VktBgN53z2ivJn1+e4r4RjfSl+pn8PtLI5I AXq7WCy83gm4d9EMBUhwFVPIARNlLpkySukjoBJ9af9ezhswt0IosOENzGDczPbre8m1 CJgn6lTYA3gkv2YfBYZ/N4JDdSE8jxTwB+dpBB3laFCkIr3eUpbKvOXxpwgQ03BqkqeL XOaw== X-Gm-Message-State: APjAAAUKtlZMEFdvNvq7WS/BVeFlPByhbvuMLIqo4RQPtSc0nHgvoTT3 cgQZ+CMn/qpsiu5TUitG6hc= X-Google-Smtp-Source: APXvYqw/Rk1HO4LPlPbWBMuiTAgE3dOIrv9Mn4hWI/VmFC5SoleWU4B7t57e/CasMTGHHDYv4kv2KA== X-Received: by 2002:a05:600c:2301:: with SMTP id 1mr10852998wmo.143.1574959829103; Thu, 28 Nov 2019 08:50:29 -0800 (PST) Received: from localhost (pD9E518ED.dip0.t-ipconnect.de. [217.229.24.237]) by smtp.gmail.com with ESMTPSA id a15sm25776678wrx.81.2019.11.28.08.50.27 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 28 Nov 2019 08:50:27 -0800 (PST) Date: Thu, 28 Nov 2019 17:50:26 +0100 From: Thierry Reding To: "Rafael J. Wysocki" Cc: "Rafael J . Wysocki" , Len Brown , Pavel Machek , Greg Kroah-Hartman , Dmitry Osipenko , Linux PM , dri-devel , linux-tegra Subject: Re: [PATCH 1/2] PM / runtime: Allow drivers to override runtime PM behaviour on sleep Message-ID: <20191128163623.GA2382107@ulmo> References: <20191128160314.2381249-1-thierry.reding@gmail.com> <20191128160314.2381249-2-thierry.reding@gmail.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="0F1p//8PRICkK4MW" Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.12.2 (2019-09-21) Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org --0F1p//8PRICkK4MW Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Thu, Nov 28, 2019 at 05:14:51PM +0100, Rafael J. Wysocki wrote: > On Thu, Nov 28, 2019 at 5:03 PM Thierry Reding = wrote: > > > > From: Thierry Reding > > > > Currently the driver PM core will automatically acquire a runtime PM > > reference for devices before system sleep is entered. This is needed > > to avoid potential issues related to devices' parents getting put to > > runtime suspend at the wrong time and causing problems with their > > children. >=20 > Not only for that. >=20 > > In some cases drivers are carefully written to avoid such issues and > > the default behaviour can be changed to allow runtime PM to operate > > regularly during system sleep. >=20 > But this change breaks quite a few assumptions in the core too, so no, > it can't be made. Anything in particular that I can look at? I'm not seeing any issues when I test this, which could of course mean that I'm just getting lucky. One thing that irritated me is that I think this used to work. I do recall testing suspend/resume a few years ago and devices would get properly runtime suspended/resumed. I did some digging but couldn't find anything that would have had an impact on this. Given that this is completely opt-in feature, why are you categorically NAK'ing this? Is there some other alternative that I can look into? Thierry --0F1p//8PRICkK4MW Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAABCAAdFiEEiOrDCAFJzPfAjcif3SOs138+s6EFAl3f+tAACgkQ3SOs138+ s6F4mBAAqcwu+TStcK/qpZpkwObpVPR3H5IoPOrDpq8MN9UfrWpbf4uaAcUPdVMj 7yMCZQT8etpz6ZSoyDATX4QqU5RYmAYcYQpVEzHNQ4WryTkba8Z6ElbOZMhlESfs rNIHFvtYsBwvjPCq4VV4gdjodlKiarKCsKogOwP4CmPGOph0j4bdwyxpuUMhB+bd nrxkDeDzHNGHqRgg9uGVt23icJnMqlWAl+NCkxvTCzpt3r0BwT2TW4xnZ6IEx9Rx rcimhfWk9WxMkAKeYK1q9CZBwSeaEMkZ9LtmH242j9rTQj7UiEKnWgm8ogzIsq2X /ZtPeZ95g5cNGzMJTrmxvteNvoIv2ROaKiOI12HrEAfFtFoHt9sotcNS0awSm5eG 6Yfle+/XfnVyBk+3mPX43r6hULcicnLY281NZ0YP+Av8y40HD0I+ynrjtByj/c3M XZGsgVEPPNioiPPhKo3i+mbIGqfTiA1NeCb6EP+zHaMkqsswxSLlSckGXb3O3rdc W0C0KZByR7PkzohlsTSnuV5edDwXWM0lfsBWEtL4PJG7ukNYHCifM4B2IW6ANc40 ACLA3rShB7oY9fuxtVDd4/Q/CK4r+4qLntQ9cF09g0NKUgs7HnIXKbMdcd0WYyWB 5S3TBt8Bir2B64eaa5x/Sr12uLRm+kkzWQMopKNUpI3Dt4Q8D1k= =U0Wg -----END PGP SIGNATURE----- --0F1p//8PRICkK4MW--