From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Tue, 8 Jan 2008 17:11:20 +0100 From: Robert Schwebel To: Simon Richter Subject: Re: Generic MMC-over-SPI binding? Message-ID: <20080108161120.GC3177@pengutronix.de> References: <47838708.5050008@hogyros.de> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 In-Reply-To: <47838708.5050008@hogyros.de> Cc: linuxppc-dev@ozlabs.org, linuxppc-embedded@ozlabs.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Tue, Jan 08, 2008 at 03:22:00PM +0100, Simon Richter wrote: > in an embedded system similar to the lite5200 board, there is an MMC > card socket connected to one of the PSCs. Ideally, I'd like to express > this fact via the device tree and have the kernel bind the mmc-spi > driver to the SPI interface, but I cannot find any place where to insert > this code that I feel comfortable with. > > - It is not a board-specific thing, because any board can just use any > SPI bus for MMC. > > - The mmc-spi driver appears to be platform independent, so I'm not > sure OF bindings should be added to it. > > - The generic device tree scanning does not contain any special cases > yet, so I don't want to add one. > > My current thought is to create a new driver that just handles MMC on > PSCs in SPI mode by gluing all the relevant drivers together, but that > doesn't seem optimal to me either. You know this driver? http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=blob;f=drivers/mmc/host/mmc_spi.c;h=365024b83d3da9df9b6e4f7a9d4cf6d216ba523d;hb=HEAD Or is your question how to express this in the device tree? Robert -- Dipl.-Ing. Robert Schwebel | http://www.pengutronix.de Pengutronix - Linux Solutions for Science and Industry Handelsregister: Amtsgericht Hildesheim, HRA 2686 Hannoversche Str. 2, 31134 Hildesheim, Germany Phone: +49-5121-206917-0 | Fax: +49-5121-206917-9