From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752194AbbCYLCn (ORCPT ); Wed, 25 Mar 2015 07:02:43 -0400 Received: from mail-la0-f45.google.com ([209.85.215.45]:33607 "EHLO mail-la0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751212AbbCYLCk (ORCPT ); Wed, 25 Mar 2015 07:02:40 -0400 Date: Wed, 25 Mar 2015 12:02:31 +0100 From: Johan Hovold To: Bartlomiej Zolnierkiewicz Cc: Johan Hovold , Lee Jones , Samuel Ortiz , Support Opensource , Milo Kim , patches@opensource.wolfsonmicro.com, Fabio Estevam , Marek Szyprowski , linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 0/5] mfd: Fix platform device ids to avoid probe failure Message-ID: <20150325110231.GC10412@localhost> References: <1426879403-19265-1-git-send-email-b.zolnierkie@samsung.com> <20150323100718.GD3557@localhost> <2485401.Gb44YTtKCE@amdc1032> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <2485401.Gb44YTtKCE@amdc1032> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Mar 23, 2015 at 02:11:50PM +0100, Bartlomiej Zolnierkiewicz wrote: > On Monday, March 23, 2015 11:07:18 AM Johan Hovold wrote: > > On Fri, Mar 20, 2015 at 08:23:18PM +0100, Bartlomiej Zolnierkiewicz wrote: > > > > > Commit 6e3f62f0793e ("mfd: core: Fix platform-device id generation") > > > changed the way platform device ids are generated from mfd id base and > > > cell ids in mfd_add_device(). Unfortunately the change in question > > > breaks mfd drivers which are using mfd_add_devices() with mfd id base > > > equal to -1 and non-zero cell ids (used to distinguish cells with > > > the same name field). The result is that mfd core tries to register > > > platform devices with the same name which obviously fails and leads > > > to mfd device probe failure. > > > > First of all, thanks for finding these. I obviously overlooked this > > class of drivers when fixing the device-id generation. > > > > > Changing mfd_add_devices() mfd id base from -1 to 0 and at the same > > > time setting proper cell ids for all cells fixes the issue. > > > > This is however not the right fix. Instead you should be using > > PLATFORM_DEVID_AUTO and keep the non-zero cell-ids as is, as this will > > allow more than one mfd-device to be registered without resorting to > > hacks. > > Conversion of a driver to use PLATFORM_DEVID_AUTO changes names of > all platform devices registered by the driver. In my patchset I just > tried to restore the broken functionality (patch that broke it went > in v3.19). I thought that it was the best solution for v3.19 and > v4.0-rc4 (then PLATFORM_DEVID_AUTO conversion can be done sometime > later, i.e. in v4.1). I think you're right. We should do the conversion to PLATFORM_DEVID_AUTO later. I'm responding to this mail with two patches for v4.0 fixing the da9052 driver, which is currently broken although not in the way suggested by your v1-series, and the other drivers you identified by doing a partial revert of commit 6e3f62f0793e ("mfd: core: Fix platform-device id generation"). Thanks, Johan