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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED 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 86D3FC3279B for ; Wed, 4 Jul 2018 10:50:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 486472413A for ; Wed, 4 Jul 2018 10:50:26 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 486472413A Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=loewensteinmedical.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933531AbeGDKuW (ORCPT ); Wed, 4 Jul 2018 06:50:22 -0400 Received: from mail.steuer-voss.de ([85.183.69.95]:42934 "EHLO mail.steuer-voss.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932594AbeGDKuU (ORCPT ); Wed, 4 Jul 2018 06:50:20 -0400 X-Virus-Scanned: Debian amavisd-new at mail.steuer-voss.de Received: by mail.steuer-voss.de (Postfix, from userid 1000) id CEF4041C99; Wed, 4 Jul 2018 12:50:16 +0200 (CEST) Received: from localhost (localhost [127.0.0.1]) by mail.steuer-voss.de (Postfix) with ESMTP id C643841C98; Wed, 4 Jul 2018 12:50:16 +0200 (CEST) Date: Wed, 4 Jul 2018 12:50:16 +0200 (CEST) From: Nikolaus Voss X-X-Sender: nv@fox.voss.local To: Andy Shevchenko cc: Sudeep Holla , Srinath Mannam , "Voss, Dr. Nikolaus" , "Rafael J. Wysocki" , Len Brown , Ray Jui , Vladimir Olovyannikov , Vikram Prakash , Scott Branden , ACPI Devel Maling List , Linux Kernel Mailing List , nv@vosn.de Subject: Re: [RFC PATCH] ACPI: bus: match of_device_id using acpi device In-Reply-To: Message-ID: References: <1530609760-8919-1-git-send-email-srinath.mannam@broadcom.com> <8518137d-c859-657e-844f-51720f6ef8dd@arm.com> User-Agent: Alpine 2.20 (DEB 67 2015-01-07) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 4 Jul 2018, Andy Shevchenko wrote: > On Wed, Jul 4, 2018 at 1:17 PM, Nikolaus Voss > wrote: >> On Wed, 4 Jul 2018, Sudeep Holla wrote: >>> On 04/07/18 10:32, Andy Shevchenko wrote: >>>> On Wed, Jul 4, 2018 at 6:37 AM, Srinath Mannam >>>> wrote: > >>> +1 on NACK for this and anything else that abuse PRP0001 as a short cut >>> approach. >> This is no abuse but exactly what PRP0001 is meant for. The basic idea of >> PRP0001 is to reuse DT "compatible" strings in ACPI namespace, see >> Documentation/acpi/enumeration.txt. Reusing also means getting access to the >> of_device_id. > > The idea was for almost DIY and / or manufacturer to develop a > prototype without modifying match code and faking ACPI IDs. > That's why the target of PRP0001 is almost sensors connected to I2C and SPI. > > That's why I agreed on your patch to help with this. But! The proper > solution for the devices (device manufacturer) is to allocate an ACPI > ID and provide a corresponding table to the driver. > > This is my understanding of that exercise. Rafael can correct me. This is not meant as a short cut for device manufacturers. The patch is meant to make PRP0001 work when access to specific driver_data is needed. I see nothing bad with it. >> Allocating an ACPI id for an already existing DT driver is redundant, isn't >> it? > > It is not. The driver won't work any better with it. The driver code gets another table as big as of_device_id table. Can you give me a hint what the added value is? Niko