From mboxrd@z Thu Jan 1 00:00:00 1970 From: simon-wM4F9T/ekXmXDw4h08c5KA@public.gmane.org Subject: Re: Poulsbo I2C - /dev/i2c not seen when loading i2c-dev Date: Fri, 8 Apr 2011 16:11:48 -0400 Message-ID: <0bd85f87b0023c4c1cd417a732789f36.squirrel@host171.canaca.com> References: <20110401121027.49ce012b@endymion.delvare> <22a6003c213a91452d2a7312e4e5ad32.squirrel@host171.canaca.com> <20110406192059.369c3143@endymion.delvare> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7BIT Return-path: In-Reply-To: <20110406192059.369c3143-R0o5gVi9kd7kN2dkZ6Wm7A@public.gmane.org> Sender: linux-i2c-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org Cc: linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-i2c@vger.kernel.org >> I got a bit further, if I boot the device with the 'acpi=off' kernel >> option then I can modprobe both lpc_sch and i2c_dev, at which point >> i2c-detect works fine. > > As expected. but acpi=off is a little harsh. acpi_enforce_resources=no > would work too, and is less risky. Jean & I both (independantly) knocked up quick patches to 'lpc_sch' to allow it to load should any of the subsystems (GPIO or SMBus) load OK - it was previously failing at the first subsystem failure. This gave me access to the I2C controller whilst ACPI was active. Start discussion on whether this is a good idea... > * As I seem to understand that the board is developed by your own > company, you should ask the BIOS developers what they are up to. They > should be able to tell you if the ACPI code above is intended and > needed, or if it can be dropped (together with the PHO operation > region.) It's nice that you assume some level of competence here ;-) Simon.