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=-10.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham 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 85543C433DB for ; Wed, 10 Feb 2021 20:48:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5436264EDC for ; Wed, 10 Feb 2021 20:48:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233011AbhBJUsd (ORCPT ); Wed, 10 Feb 2021 15:48:33 -0500 Received: from mga03.intel.com ([134.134.136.65]:8299 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232282AbhBJUs1 (ORCPT ); Wed, 10 Feb 2021 15:48:27 -0500 IronPort-SDR: DrFD40uO1w6vOauZFgwjkAf0iT8H54szb62wt7PXoSjsh2h+8/TSGUXIoYm8I9doGLiNgWvhKh RmPunkgOaj5Q== X-IronPort-AV: E=McAfee;i="6000,8403,9891"; a="182215861" X-IronPort-AV: E=Sophos;i="5.81,169,1610438400"; d="scan'208";a="182215861" Received: from orsmga008.jf.intel.com ([10.7.209.65]) by orsmga103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 10 Feb 2021 12:46:40 -0800 IronPort-SDR: J36Gjftpz/7EyfshVRDRSHf30+e56BO6/YCjoGNzZJ9ECSRnBH+tQ+yHgahFXDm9ZrUD7bm4ax iIV2WjYEIjJQ== X-IronPort-AV: E=Sophos;i="5.81,169,1610438400"; d="scan'208";a="396931244" Received: from paasikivi.fi.intel.com ([10.237.72.42]) by orsmga008-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 10 Feb 2021 12:46:37 -0800 Received: from paasikivi.fi.intel.com (localhost [127.0.0.1]) by paasikivi.fi.intel.com (Postfix) with SMTP id 9D1C62011B; Wed, 10 Feb 2021 22:46:35 +0200 (EET) Date: Wed, 10 Feb 2021 22:46:35 +0200 From: Sakari Ailus To: Bartosz Golaszewski Cc: "Rafael J. Wysocki" , linux-i2c , Wolfram Sang , ACPI Devel Maling List , LKML , Greg Kroah-Hartman , Rajmohan Mani , Tomasz Figa , Bingbu Cao , Chiranjeevi Rapolu , Hyungwoo Yang , linux-media Subject: Re: [PATCH v10 7/7] at24: Support probing while off Message-ID: <20210210204635.GD3@paasikivi.fi.intel.com> References: <20210205132505.20173-8-sakari.ailus@linux.intel.com> <20210209162343.GF32460@paasikivi.fi.intel.com> <20210209165418.GG32460@paasikivi.fi.intel.com> <20210210080311.GA3@paasikivi.fi.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org On Wed, Feb 10, 2021 at 01:26:51PM +0100, Bartosz Golaszewski wrote: > On Wed, Feb 10, 2021 at 9:41 AM Sakari Ailus > wrote: > > > > On Tue, Feb 09, 2021 at 05:58:12PM +0100, Rafael J. Wysocki wrote: > > > On Tue, Feb 9, 2021 at 5:54 PM Sakari Ailus > > > wrote: > > > > > > > > On Tue, Feb 09, 2021 at 05:42:45PM +0100, Rafael J. Wysocki wrote: > > > > > On Tue, Feb 9, 2021 at 5:23 PM Sakari Ailus > > > > > wrote: > > > > > > > > > > > > Hi Bartosz, Rafael, > > > > > > > > > > > > On Tue, Feb 09, 2021 at 04:49:37PM +0100, Bartosz Golaszewski wrote: > > > > > > > On Mon, Feb 8, 2021 at 5:54 PM Rafael J. Wysocki wrote: > > > > > > > > > > > > > > > > On Mon, Feb 8, 2021 at 5:44 PM Bartosz Golaszewski > > > > > > > > wrote: > > > > > > > > > > > > > > > > > > On Fri, Feb 5, 2021 at 2:25 PM Sakari Ailus > > > > > > > > > wrote: > > > > > > > > > > > > > > > > > > > > In certain use cases (where the chip is part of a camera module, and the > > > > > > > > > > camera module is wired together with a camera privacy LED), powering on > > > > > > > > > > the device during probe is undesirable. Add support for the at24 to > > > > > > > > > > execute probe while being powered off. For this to happen, a hint in form > > > > > > > > > > of a device property is required from the firmware. > > > > > > > > > > > > > > > > > > > > Signed-off-by: Sakari Ailus > > > > > > > > > > Reviewed-by: Tomasz Figa > > > > > > > > > > --- > > > > > > > > > > > > > > > > > > I'll ack this but I still claim that the name > > > > > > > > > acpi_dev_state_low_power() is super misleading for this use-case and > > > > > > > > > I've been saying that for 10 versions now with everyone just ignoring > > > > > > > > > my remarks. :/ > > > > > > > > > > > > > > > > Well, the function in question simply checks if the current ACPI power > > > > > > > > state of the device is different from "full power", so its name > > > > > > > > appears to be quite adequate to me. > > > > > > > > > > > > > > > > If the way in which it is used is confusing, though, I guess > > > > > > > > explaining what's going on would be welcome. > > > > > > > > > > > > > > > > > > > > > > Yes, I have explained it multiple time already - last time at v9 of this series: > > > > > > > > > > > > > > https://www.spinics.net/lists/kernel/msg3816807.html > > > > > > > > > > > > How about adding this to the description of acpi_dev_state_low_power(): > > > > > > > > > > > > -----------8<-------------- > > > > > > * This function is intended to be used by drivers to tell whether the device > > > > > > * is in low power state (D1--D3cold) in driver's probe or remove function. See > > > > > > * Documentation/firmware-guide/acpi/low-power-probe.rst for more information. > > > > > > -----------8<-------------- > > > > > > > > > > This information is already there in the kerneldoc description of that > > > > > function AFAICS. > > > > > > > > Ok, the D states are mentioned already. But how to use it is not, nor > > > > there's a reference to the ReST file. I think that wouldn't hurt. > > > > > > > > > > > > > > I was thinking about adding an explanation comment to the caller. > > > > > > > > I think it'd be best if the function name would convey that without a > > > > comment that should then be added to all callers. How about calling the > > > > function e.g. acpi_dev_state_d0() and negating the return value? The D0 > > > > state is well defined and we could do this without adding new terms. > > > > > > That would work for me. > > > > Bartosz, would that work for you? > > > > I'd call the temporary variable in the at24 driver e.g. "full_power". > > > > Yes, that works, go ahead and thank you. Thanks! I'll send v11 soon. -- Sakari Ailus