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=-11.5 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable 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 7D915C433E7 for ; Tue, 1 Sep 2020 20:29:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 695A1206FA for ; Tue, 1 Sep 2020 20:29:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727943AbgIAU3U (ORCPT ); Tue, 1 Sep 2020 16:29:20 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44054 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726269AbgIAU3U (ORCPT ); Tue, 1 Sep 2020 16:29:20 -0400 Received: from hillosipuli.retiisi.org.uk (hillosipuli.retiisi.org.uk [IPv6:2a01:4f9:c010:4572::81:2]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8E200C061244; Tue, 1 Sep 2020 13:29:19 -0700 (PDT) Received: from valkosipuli.localdomain (valkosipuli.retiisi.org.uk [IPv6:2a01:4f9:c010:4572::80:2]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by hillosipuli.retiisi.org.uk (Postfix) with ESMTPS id 28220634C8C; Tue, 1 Sep 2020 23:28:55 +0300 (EEST) Received: from sailus by valkosipuli.localdomain with local (Exim 4.92) (envelope-from ) id 1kDCtj-0001BF-2L; Tue, 01 Sep 2020 23:28:55 +0300 Date: Tue, 1 Sep 2020 23:28:55 +0300 From: Sakari Ailus To: Sakari Ailus Cc: Randy Dunlap , linux-i2c@vger.kernel.org, Wolfram Sang , "Rafael J. Wysocki" , linux-acpi@vger.kernel.org, Bingbu Cao , linux-media@vger.kernel.org, Chiranjeevi Rapolu , Hyungwoo Yang , Bartosz Golaszewski , Arnd Bergmann , linux-kernel@vger.kernel.org, Greg Kroah-Hartman , rajmohan.mani@intel.com, Tomasz Figa , "Qiu, Tian Shu" Subject: Re: [PATCH v6 6/6] Documentation: ACPI: Document allow-low-power-probe _DSD property Message-ID: <20200901202854.GA4392@valkosipuli.retiisi.org.uk> References: <20200826115432.6103-1-sakari.ailus@linux.intel.com> <20200826115432.6103-7-sakari.ailus@linux.intel.com> <20200827132822.GI24582@paasikivi.fi.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20200827132822.GI24582@paasikivi.fi.intel.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Aug 27, 2020 at 04:28:22PM +0300, Sakari Ailus wrote: > On Wed, Aug 26, 2020 at 11:06:22AM -0700, Randy Dunlap wrote: > > On 8/26/20 4:54 AM, Sakari Ailus wrote: > > > Document the probe-low-power _DSD property and how it is used with I²C > > > drivers. > > > > > > Signed-off-by: Sakari Ailus > > > --- > > > .../acpi/dsd/allow-low-power-probe.rst | 28 +++++++++++++++++++ > > > Documentation/firmware-guide/acpi/index.rst | 1 + > > > 2 files changed, 29 insertions(+) > > > create mode 100644 Documentation/firmware-guide/acpi/dsd/allow-low-power-probe.rst > > > > > > diff --git a/Documentation/firmware-guide/acpi/dsd/allow-low-power-probe.rst b/Documentation/firmware-guide/acpi/dsd/allow-low-power-probe.rst > > > new file mode 100644 > > > index 0000000000000..6fcc89162b898 > > > --- /dev/null > > > +++ b/Documentation/firmware-guide/acpi/dsd/allow-low-power-probe.rst > > > @@ -0,0 +1,28 @@ > > > +.. SPDX-License-Identifier: GPL-2.0 > > > + > > > +====================================== > > > +Probing I²C devices in low power state > > > +====================================== > > > + > > > +Introduction > > > +============ > > > + > > > +In some cases it may be preferred to leave certain devices powered off for the > > > +entire system bootup if powering on these devices has adverse side effects, > > > +beyond just powering on the said device. Linux recognizes the _DSD property > > > +"allow-low-power-probe" that can be used for this purpose. > > > + > > > +How it works > > > +============ > > > + > > > +The property "allow-low-power-probe" boolean property may be used to tell Linux > > > > Drop the first "property". > > > > Thanks, will fix for v7. > > > > +that the I²C framework should instruct the kernel ACPI framework to leave the > > > +device in the low power state. If the driver indicates its support for this by > > > +setting the I2C_DRV_FL_ALLOW_LOW_POWER_PROBE flag in struct i2c_driver.flags > > This is leftover from v5 actually, I'll change the documentation to mention > the allow_low_power_probe as well. Hmm. It seems I ended up sending the set with the flags field. I'll keep it as-is if that's okay... -- Sakari Ailus