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=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 251F3C433E0 for ; Tue, 9 Feb 2021 16:56:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BF3A860C3F for ; Tue, 9 Feb 2021 16:56:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232983AbhBIQ4N (ORCPT ); Tue, 9 Feb 2021 11:56:13 -0500 Received: from mga17.intel.com ([192.55.52.151]:38815 "EHLO mga17.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232762AbhBIQ4K (ORCPT ); Tue, 9 Feb 2021 11:56:10 -0500 IronPort-SDR: +/Ed0S3JqYWMvdhzwsMFahmb/NPuoQqIAEdC0ZKwl/EA4LwnhkMQRLyipw8ApBzoJUEL7qPIYr d/2uNitPu7sQ== X-IronPort-AV: E=McAfee;i="6000,8403,9890"; a="161664803" X-IronPort-AV: E=Sophos;i="5.81,165,1610438400"; d="scan'208";a="161664803" Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by fmsmga107.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 09 Feb 2021 08:54:23 -0800 IronPort-SDR: a1XALXBRo4pL2BpBztVFedROLQixuqmREpPrOj4BWOiUTNQAD3ZIooEZwOdtaF+h4hdY7wMBly V+JRIaFeOyww== X-IronPort-AV: E=Sophos;i="5.81,165,1610438400"; d="scan'208";a="412260388" Received: from paasikivi.fi.intel.com ([10.237.72.42]) by fmsmga004-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 09 Feb 2021 08:54:20 -0800 Received: by paasikivi.fi.intel.com (Postfix, from userid 1000) id 41210206D0; Tue, 9 Feb 2021 18:54:18 +0200 (EET) Date: Tue, 9 Feb 2021 18:54:18 +0200 From: Sakari Ailus To: "Rafael J. Wysocki" Cc: Bartosz Golaszewski , 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: <20210209165418.GG32460@paasikivi.fi.intel.com> References: <20210205132505.20173-1-sakari.ailus@linux.intel.com> <20210205132505.20173-8-sakari.ailus@linux.intel.com> <20210209162343.GF32460@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-i2c@vger.kernel.org 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. -- Sakari Ailus