From mboxrd@z Thu Jan 1 00:00:00 1970 From: Feng Tang Subject: Re: i2c-eg20t: regression since i2c_add_numbered_adapter change Date: Wed, 22 Aug 2012 15:29:18 +0800 Message-ID: <20120822152918.3e59616e@feng-i7> References: <4401854.hVfHzgeqjT@ws-stein> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <4401854.hVfHzgeqjT@ws-stein> Sender: linux-i2c-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Alexander Stein Cc: linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, "Jean Delvare (PC drivers, core)" , "Ben Dooks (embedded platforms)" , Tomoya MORINAGA List-Id: linux-i2c@vger.kernel.org On Wed, 22 Aug 2012 08:30:35 +0200 Alexander Stein wrote: > Hello, > > I just noticed the 3.4 linux kernel fails to sucessfully probe the i2c-eg20t > driver. I returns with EBUSY error. It worked on the 3.0 kernel. To my view it > is caused the commit 07e8a51ff68353e01d795cceafbac9f54c49132b ( i2c-eg20t: use > i2c_add_numbered_adapter to get a fixed bus number). > The reason it actually fails is that the i2c-isch driver is registered > beforehand which gets bus number 0. But this one is the bus number the eg20t > driver wants to register. Make sense. > A possibility is that if i2c_add_numbered_adapter failed with EBUSY just use > i2c_add_adapter to get at least the driver working, but with a non-fixed bus > number. Opinions? Or can we give it a fixed offset, like let the i2c_eg20t controller bus number start with 4? I don't expect there will be more than 4 other i2c controllers on EG20T compatible platforms. Thanks, Feng