From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arnd Bergmann Subject: Re: [PATCH 10/10] drivers: misc: use module_platform_driver_probe() Date: Tue, 19 Mar 2013 17:59:27 +0000 Message-ID: <201303191759.27762.arnd@arndb.de> References: <1363266691-15757-1-git-send-email-fabio.porcedda@gmail.com> <201303191648.31527.arnd@arndb.de> Mime-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Return-path: Received: from moutng.kundenserver.de ([212.227.17.9]:63044 "EHLO moutng.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753967Ab3CSSAQ (ORCPT ); Tue, 19 Mar 2013 14:00:16 -0400 In-Reply-To: Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Fabio Porcedda Cc: Geert Uytterhoeven , H Hartley Sweeten , "linux-kernel@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , "linux-media@vger.kernel.org" , "linux-ide@vger.kernel.org" , "lm-sensors@lm-sensors.org" , "linux-input@vger.kernel.org" , "linux-fbdev@vger.kernel.org" , Greg Kroah-Hartman , Hans-Christian Egtvedt , Grant Likely On Tuesday 19 March 2013, Fabio Porcedda wrote: > On Tue, Mar 19, 2013 at 5:48 PM, Arnd Bergmann wrote: > > On Tuesday 19 March 2013, Geert Uytterhoeven wrote: > >> Hmm, so we may have drivers that (now) work perfectly fine with > >> module_platform_driver_probe()/platform_driver_probe(), but will start > >> failing suddenly in the future? > > > > They will fail if someone changes the initialization order. That would > > already break drivers before deferred probing support (and was the reason > > we added feature in the first place), but now we can be much more liberal > > with the order in which drivers are initialized, except when they are > > using platform_driver_probe() > > > >> I guess we need a big fat WARN_ON(-EPROBE_DEFER) in > >> platform_driver_probe() to catch these? > > > > Yes, very good idea. > > If it's fine, I'll send a patch for that. That would be cool, yes. I looked at it earlier (after sending my email above) and couldn't find an easy way to do it though, because platform_drv_probe does not know whether it is called from platform_driver_probe or not. Maybe using something other than platform_driver_register would work here. Arnd From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757297Ab3CSSAS (ORCPT ); Tue, 19 Mar 2013 14:00:18 -0400 Received: from moutng.kundenserver.de ([212.227.17.9]:63044 "EHLO moutng.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753967Ab3CSSAQ (ORCPT ); Tue, 19 Mar 2013 14:00:16 -0400 From: Arnd Bergmann To: Fabio Porcedda Subject: Re: [PATCH 10/10] drivers: misc: use module_platform_driver_probe() Date: Tue, 19 Mar 2013 17:59:27 +0000 User-Agent: KMail/1.12.2 (Linux/3.8.0-8-generic; KDE/4.3.2; x86_64; ; ) Cc: Geert Uytterhoeven , H Hartley Sweeten , "linux-kernel@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , "linux-media@vger.kernel.org" , "linux-ide@vger.kernel.org" , "lm-sensors@lm-sensors.org" , "linux-input@vger.kernel.org" , "linux-fbdev@vger.kernel.org" , "Greg Kroah-Hartman" , "Hans-Christian Egtvedt" , Grant Likely References: <1363266691-15757-1-git-send-email-fabio.porcedda@gmail.com> <201303191648.31527.arnd@arndb.de> In-Reply-To: MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <201303191759.27762.arnd@arndb.de> X-Provags-ID: V02:K0:SLjbsCDkB+PZsHDMeU2POGqnZ8bcvPfesHFk2ztvwsl RqeNHL2H9b3SEpEVogLJK0msGuISv9eO9UMWa4l4TTdB2QLBPj XpUnCYRa6tptmrJh8LNlgmbb2OWv+qcmyhbCPmb8/NyhxeAWVN tW45XToz4pHX/NKKx8joryFKelyMJIMtU7+EB4WLYINbVHEgDV htPBM4Pr5x1SxdGs+uB6bU1zk94YBvCjDH8KxUh+s3HbWNB2ZU Me72qBJGvbCz2c3hkWv7YfkddBdZmL7UNS0+BxOjhSz1Eq0hu0 eHTD6jelyBFz89G7agB0uYPOO76YU3f6QqtstkB6c0YMnyEteN iegFQwIzNfTZCUd2TWqw= Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tuesday 19 March 2013, Fabio Porcedda wrote: > On Tue, Mar 19, 2013 at 5:48 PM, Arnd Bergmann wrote: > > On Tuesday 19 March 2013, Geert Uytterhoeven wrote: > >> Hmm, so we may have drivers that (now) work perfectly fine with > >> module_platform_driver_probe()/platform_driver_probe(), but will start > >> failing suddenly in the future? > > > > They will fail if someone changes the initialization order. That would > > already break drivers before deferred probing support (and was the reason > > we added feature in the first place), but now we can be much more liberal > > with the order in which drivers are initialized, except when they are > > using platform_driver_probe() > > > >> I guess we need a big fat WARN_ON(-EPROBE_DEFER) in > >> platform_driver_probe() to catch these? > > > > Yes, very good idea. > > If it's fine, I'll send a patch for that. That would be cool, yes. I looked at it earlier (after sending my email above) and couldn't find an easy way to do it though, because platform_drv_probe does not know whether it is called from platform_driver_probe or not. Maybe using something other than platform_driver_register would work here. Arnd From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arnd Bergmann Date: Tue, 19 Mar 2013 17:59:27 +0000 Subject: Re: [PATCH 10/10] drivers: misc: use module_platform_driver_probe() Message-Id: <201303191759.27762.arnd@arndb.de> List-Id: References: <1363266691-15757-1-git-send-email-fabio.porcedda@gmail.com> <201303191648.31527.arnd@arndb.de> In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-arm-kernel@lists.infradead.org On Tuesday 19 March 2013, Fabio Porcedda wrote: > On Tue, Mar 19, 2013 at 5:48 PM, Arnd Bergmann wrote: > > On Tuesday 19 March 2013, Geert Uytterhoeven wrote: > >> Hmm, so we may have drivers that (now) work perfectly fine with > >> module_platform_driver_probe()/platform_driver_probe(), but will start > >> failing suddenly in the future? > > > > They will fail if someone changes the initialization order. That would > > already break drivers before deferred probing support (and was the reason > > we added feature in the first place), but now we can be much more liberal > > with the order in which drivers are initialized, except when they are > > using platform_driver_probe() > > > >> I guess we need a big fat WARN_ON(-EPROBE_DEFER) in > >> platform_driver_probe() to catch these? > > > > Yes, very good idea. > > If it's fine, I'll send a patch for that. That would be cool, yes. I looked at it earlier (after sending my email above) and couldn't find an easy way to do it though, because platform_drv_probe does not know whether it is called from platform_driver_probe or not. Maybe using something other than platform_driver_register would work here. Arnd From mboxrd@z Thu Jan 1 00:00:00 1970 From: arnd@arndb.de (Arnd Bergmann) Date: Tue, 19 Mar 2013 17:59:27 +0000 Subject: [PATCH 10/10] drivers: misc: use module_platform_driver_probe() In-Reply-To: References: <1363266691-15757-1-git-send-email-fabio.porcedda@gmail.com> <201303191648.31527.arnd@arndb.de> Message-ID: <201303191759.27762.arnd@arndb.de> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Tuesday 19 March 2013, Fabio Porcedda wrote: > On Tue, Mar 19, 2013 at 5:48 PM, Arnd Bergmann wrote: > > On Tuesday 19 March 2013, Geert Uytterhoeven wrote: > >> Hmm, so we may have drivers that (now) work perfectly fine with > >> module_platform_driver_probe()/platform_driver_probe(), but will start > >> failing suddenly in the future? > > > > They will fail if someone changes the initialization order. That would > > already break drivers before deferred probing support (and was the reason > > we added feature in the first place), but now we can be much more liberal > > with the order in which drivers are initialized, except when they are > > using platform_driver_probe() > > > >> I guess we need a big fat WARN_ON(-EPROBE_DEFER) in > >> platform_driver_probe() to catch these? > > > > Yes, very good idea. > > If it's fine, I'll send a patch for that. That would be cool, yes. I looked at it earlier (after sending my email above) and couldn't find an easy way to do it though, because platform_drv_probe does not know whether it is called from platform_driver_probe or not. Maybe using something other than platform_driver_register would work here. Arnd