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=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 8D011C64E8A for ; Mon, 30 Nov 2020 18:25:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 54270206F9 for ; Mon, 30 Nov 2020 18:25:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388131AbgK3SYm (ORCPT ); Mon, 30 Nov 2020 13:24:42 -0500 Received: from mga04.intel.com ([192.55.52.120]:49189 "EHLO mga04.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388042AbgK3SYm (ORCPT ); Mon, 30 Nov 2020 13:24:42 -0500 IronPort-SDR: cO21u1Gs+DIDkXtOZoOyHp0t7zlXfN0XdDOytcT6fIGuDmCF48YE4QNq2aISQ9Qkd89HvTOXit ugI1mHvlY/Uw== X-IronPort-AV: E=McAfee;i="6000,8403,9821"; a="170121653" X-IronPort-AV: E=Sophos;i="5.78,382,1599548400"; d="scan'208";a="170121653" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga002.jf.intel.com ([10.7.209.21]) by fmsmga104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Nov 2020 10:23:01 -0800 IronPort-SDR: LAL3B3M6tmBMESxAftDHo+ddvK6h6BnOG2TFM/LinWKrkXwNlECJjHz7mgl8VAqV6rcS2o9R6t /VlLQBNZwEtw== X-IronPort-AV: E=Sophos;i="5.78,382,1599548400"; d="scan'208";a="345161635" Received: from smile.fi.intel.com (HELO smile) ([10.237.68.40]) by orsmga002-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Nov 2020 10:22:54 -0800 Received: from andy by smile with local (Exim 4.94) (envelope-from ) id 1kjnq6-00B6WE-RI; Mon, 30 Nov 2020 20:23:54 +0200 Date: Mon, 30 Nov 2020 20:23:54 +0200 From: Andy Shevchenko To: Daniel Scally Cc: linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org, linux-gpio@vger.kernel.org, linux-i2c@vger.kernel.org, linux-media@vger.kernel.org, devel@acpica.org, rjw@rjwysocki.net, lenb@kernel.org, gregkh@linuxfoundation.org, mika.westerberg@linux.intel.com, linus.walleij@linaro.org, bgolaszewski@baylibre.com, wsa@kernel.org, yong.zhi@intel.com, sakari.ailus@linux.intel.com, bingbu.cao@intel.com, tian.shu.qiu@intel.com, mchehab@kernel.org, robert.moore@intel.com, erik.kaneda@intel.com, pmladek@suse.com, rostedt@goodmis.org, sergey.senozhatsky@gmail.com, linux@rasmusvillemoes.dk, kieran.bingham+renesas@ideasonboard.com, jacopo+renesas@jmondi.org, laurent.pinchart+renesas@ideasonboard.com, jorhand@linux.microsoft.com, kitakar@gmail.com, heikki.krogerus@linux.intel.com Subject: Re: [PATCH 14/18] acpi: utils: Add function to fetch dependent acpi_devices Message-ID: <20201130182354.GW4077@smile.fi.intel.com> References: <20201130133129.1024662-1-djrscally@gmail.com> <20201130133129.1024662-15-djrscally@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201130133129.1024662-15-djrscally@gmail.com> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org On Mon, Nov 30, 2020 at 01:31:25PM +0000, Daniel Scally wrote: > ACPI devices declare themselves dependent on other devices via the _DEP > buffer. Fetching the dependee from dependent is a matter of parsing > _DEP, but currently there's no method to fetch dependent from dependee. > Add one, so we can parse sensors dependent on a PMIC from the PMIC's > acpi_driver. Do I understand correctly that it's an existing table provided by firmware that (ab)uses _DEP in such way? Note, the specification doesn't tell we may use it in this way, OTOH I don't remember if it strictly forbids such use. So, please elaborate in the commit message why you need this and pint out to the 6.5.8 "_DEP (Operation Region Dependencies)" which clearly says about OpRegions and that part already supported by ACPI in the Linux, if I'm not mistaken, need to refresh my memory. ... > + handle = adev->handle; > + > + if (!acpi_has_method(handle, "_DEP")) > + return 0; > + > + status = acpi_evaluate_reference(handle, "_DEP", NULL, &dep_handles); > + if (ACPI_FAILURE(status)) > + return 0; > + > + for (i = 0; i < dep_handles.count; i++) { > + struct acpi_device_info *info; > + > + status = acpi_get_object_info(dep_handles.handles[i], &info); > + if (ACPI_FAILURE(status)) > + continue; > + > + if (info->valid & ACPI_VALID_HID) { > + ret = acpi_bus_get_device(dep_handles.handles[i], &candidate); > + if (ret || !candidate) { > + kfree(info); > + continue; > + } > + > + if (candidate == dependee) { > + acpi_dev_put(candidate); > + kfree(info); > + return 1; > + } > + > + kfree(info); > + } > + } Can you utilize (by moving to here and export for ACPI layer the acpi_lpss_dep()? -- With Best Regards, Andy Shevchenko