From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jean Delvare Subject: Re: [PATCH][UPDATE] i2c: Add support for virtual I2C adapters Date: Thu, 29 May 2008 13:54:51 +0200 Message-ID: <20080529135451.7aa9ffde@hyperion.delvare> References: <20080528133015.GS9698@enneenne.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20080528133015.GS9698-AVVDYK/kqiJWk0Htik3J/w@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: i2c-bounces-GZX6beZjE8VD60Wz+7aTrA@public.gmane.org Errors-To: i2c-bounces-GZX6beZjE8VD60Wz+7aTrA@public.gmane.org To: Rodolfo Giometti Cc: i2c-GZX6beZjE8VD60Wz+7aTrA@public.gmane.org, Kumar Gala List-Id: linux-i2c@vger.kernel.org Hi Rodolfo, On Wed, 28 May 2008 15:30:15 +0200, Rodolfo Giometti wrote: > I'd like to know why the patches at: > > http://lists.linuxcoding.com/kernel/2006-q1/msg32516.html > > have never been applied to the main kernel tree. There are two main reasons: 1* Nobody reviewed the patches in question. I don't even remember seeing test reports about these patches, but this could as well be my defective memory. A patch affecting i2c-core definitely needs good review and testing before it can go upstream. 2* When this patch was sent, the i2c subsystem was still using the legacy model where device drivers have to probe for and instantiate their devices themselves. This model is fundamentally incompatible with a generic for of I2C multiplexing support. So I didn't pay too much attention to attempts to support multiplexing of i2c adapters because I suspected it would be ugly at best. Now that we have new-style i2c device/driver binding which follows the device driver model, it's probably the right time to think about multiplexing support again. Another reason, I guess, is that I do not have any system with a multiplexed I2C bus myself, so I can't test the code and I also lack personal motivation to push this forward. There are still some cleanups needed in i2c-core, most notably with respect to duplication and locking, and ideally I'd like to see it done before we add multiplexing support, but admittedly there is no roadmap so I can't make this a mandatory requirement. > I'd like to use them and maybe I can update them to the latest kernel > version for submission. :) You are welcome to update and resubmit the patch, however I suspect that what is needed is more than that. The code was written with the legacy model in mind, while we want to support primarily (and maybe even exclusively) the new-style binding model. -- Jean Delvare _______________________________________________ i2c mailing list i2c-GZX6beZjE8VD60Wz+7aTrA@public.gmane.org http://lists.lm-sensors.org/mailman/listinfo/i2c