From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bo Shen Subject: Re: [PATCH v3 2/2] i2c: change id to let i2c-at91 work Date: Tue, 16 Oct 2012 18:25:32 +0800 Message-ID: <507D361C.6020403@atmel.com> References: <1350293428-24551-1-git-send-email-voice.shen@atmel.com> <1350293428-24551-3-git-send-email-voice.shen@atmel.com> <20121015150244.GZ12801@game.jcrosoft.org> <507CD0CA.9010006@atmel.com> <20121016083954.GB12801@game.jcrosoft.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20121016083954.GB12801-RQcB7r2h9QmfDR2tN2SG5Ni2O/JbrIOy@public.gmane.org> Sender: linux-i2c-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Jean-Christophe PLAGNIOL-VILLARD Cc: w.sang-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org, n.voss-+umVssTZoCsb1SvskN2V4Q@public.gmane.org, khali-PUYAD+kWke1g9hUCZPvPmw@public.gmane.org, swarren-3lzwWm7+Weoh9ZMKESR00Q@public.gmane.org, linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, devicetree-discuss-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org, nicolas.ferre-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org, manabian-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, broonie-yzvPICuk2AATkU/dhu1WVueM+bqZidxxQQ4Iyu8u01E@public.gmane.org List-Id: devicetree@vger.kernel.org Hi J, On 10/16/2012 16:39, Jean-Christophe PLAGNIOL-VILLARD wrote: > On 11:13 Tue 16 Oct , Bo Shen wrote: >> Hi J, >> >> On 10/15/2012 23:02, Jean-Christophe PLAGNIOL-VILLARD wrote: >>> On 17:30 Mon 15 Oct , Bo Shen wrote: >>>> The i2c core driver will turn the platform device ID to busnum >>>> When using platfrom device ID as -1, it means dynamically assigned >>>> the busnum. When writing code, we need to make sure the busnum, >>>> and call i2c_register_board_info(int busnum, ...) to register device >>>> if using -1, we do not know the value of busnum >>>> >>>> In order to solve this issue, set the platform device ID as a fix number >>>> Here using 0 to match the busnum used in i2c_regsiter_board_info() >>>> >>>> Signed-off-by: Bo Shen >>>> --- >>> >>> can you check when this append for the first time to schedule a patch for stable too >> >> OK. I will resend it and add linux stable into the cc list. > no this not how it work > > I ask you to check which patch add the regression and then when this is > applied in the kernel we will request greg to apply it too to the stable The code is using id = -1 appear 4 years ago. And after dig, I don't find which patch cause this the regression. Sorry for that. > But before do that you MUST foudn the commit responsible > > Best Regards, > J. >