From mboxrd@z Thu Jan 1 00:00:00 1970 From: Robin Holt Subject: Xilinx iic i2c bus interface GPIO support for i2c-mux in Linux. Date: Wed, 8 Feb 2012 13:46:15 -0600 Message-ID: <20120208194615.GT14907@sgi.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline Sender: linux-i2c-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org Cc: Richard =?iso-8859-1?Q?R=F6jfors?= , Ben Dooks , info-l7gf1WXxx3uGw+nKnLezzg@public.gmane.org, Michael Lawnick , Jean Delvare , Rodolfo Giometti List-Id: linux-i2c@vger.kernel.org We are using a Xilinx FPGA which implements a series of i2c bus interfaces. We are planning on implementing a single-bit GPIO (XIIC_GPO_REG_OFFSET) which is included in that logic block to act as a MUX selector (also in the FPGA) between two separate i2c busses. This will require a GPIO driver in the linux kernel. Is it better to try and change the i2c-xiic.c code which already knows about the GPO register to handle that additional GPIO or should we be implementing the GPIO driver outside the i2c driver and then use the standard i2c-mux support available in newer kernels? Any guidance is welcome. Thanks, Robin Holt