Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753407Ab3IKJ4P (ORCPT ); Wed, 11 Sep 2013 05:56:15 -0400 Received: from cassiel.sirena.org.uk ([80.68.93.111]:51841 "EHLO cassiel.sirena.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751269Ab3IKJ4N (ORCPT ); Wed, 11 Sep 2013 05:56:13 -0400 Date: Wed, 11 Sep 2013 10:55:52 +0100 From: Mark Brown To: Aaron Lu Cc: "Rafael J. Wysocki" , Mika Westerberg , linux-i2c@vger.kernel.org, Wolfram Sang , "Rafael J. Wysocki" , linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org, Lv Zheng , linux-arm-kernel@lists.infradead.org Message-ID: <20130911095552.GI29403@sirena.org.uk> References: <1378733679-19500-1-git-send-email-mika.westerberg@linux.intel.com> <3397524.g9aUWuArnm@vostro.rjw.lan> <20130910213522.GG29403@sirena.org.uk> <2029393.u6DaKBPszu@vostro.rjw.lan> <522FC0DC.9030708@intel.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="A1AeHK3WkQzeMGLU" Content-Disposition: inline In-Reply-To: <522FC0DC.9030708@intel.com> X-Cookie: Your present plans will be successful. User-Agent: Mutt/1.5.21 (2010-09-15) X-SA-Exim-Connect-IP: 94.175.92.69 X-SA-Exim-Mail-From: broonie@sirena.org.uk Subject: Re: [PATCH RESEND 1/2] i2c: prepare runtime PM support for I2C client devices X-SA-Exim-Version: 4.2.1 (built Mon, 26 Dec 2011 16:57:07 +0000) X-SA-Exim-Scanned: Yes (on cassiel.sirena.org.uk) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2244 Lines: 53 --A1AeHK3WkQzeMGLU Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Wed, Sep 11, 2013 at 09:01:16AM +0800, Aaron Lu wrote: > Looks like, it all boils down to how many I2C devices should be allowed > for runtime PM by default and how many I2C devices should be forbidden. > , and then we allow/forbid runtime PM for the majority case in I2C core > while individual driver can still forbid/allow it in their own code. > So if the majority case is runtime PM should be allowed by default, I'm > also OK to not forbid runtime PM for I2C client device in I2C core. My > original intention to forbid runtime PM by default is to make sure no > adverse effect would occur to some I2C devices that used to work well > before runtime PM. The really big problem here is that there are I2C devices currently using runtime PM quite happily and forbidding it by default will break them. In general though requiring userspace to manually activate power saving features isn't going to make people happy. --A1AeHK3WkQzeMGLU Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.21 (GNU/Linux) iQIcBAEBAgAGBQJSMD4lAAoJELSic+t+oim9MKAP/jfLtDWtc+xh1vePSJpB1iDP 6FDiNmIpxf9Sa4o7J614lrEwB8FkBH2fhWkJXZVPsZZ0tI3n75uXfasJmwxDH9Cm mfPK+Xl7gxss+qiHL/vhlGe2k+ti1bE7wprEE1MXZpGbgCuXPgvRyaZvpzMabqyF DHiRqr/dVwaBIwNveMaaiwTLvbT83V+/MWMYCzVUl2xQ1LoDx52JsnyBDy4oLAWV SimlDwDY4kHZP+mRoR5kZlAkNeKpHkGktJBQHvt3oyrXn9MzMQ98LlzXhL9X6jW/ 2sP2t5pDf24Ch8WISUOHsO27Jybjdy2ZbRfhugLsGG5mMRjuqxliU0sHfrT5TIDU nzXgIeIwPueLNiw5soFmbnr4X2wa8N/EoIxrkdS34lS3Zd45n3tXDOW/UsCKP2lZ CZHcJqCbwxGGmBpwtqvs9OYC6bTtUUFzan2Dj7lZfmFSa2HtjZzHvVVXkBOQUFF9 8SMvjjZhFspxYP7vGGPdotxIoakWMwkkUTBZ9JiKTwyqC79f3a+TJW7UCCdj4Qwf WzHASdUMu/sI8WburE/aUufuysVKWACcdzFkgX91u/b3Wn9NYdz5sAhm+rxWgmMu xdq1sl7+hEuKTHO3og6mryoKDI80EgZXCsM1MBQe32cvhyuehCdAeG88q95XiGS6 WB1/8/y8XSVVUebhafYX =SvlW -----END PGP SIGNATURE----- --A1AeHK3WkQzeMGLU-- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/