From mboxrd@z Thu Jan 1 00:00:00 1970 From: Anton Vorontsov Subject: [PATCH 0/6 RFC] OF-glue devices for I2C/SPI (was: Re: [PATCH 4/7] gpiolib: implement dev_gpiochip_{add,remove} calls Date: Tue, 28 Oct 2008 20:45:32 +0300 Message-ID: <20081028174532.GA23834@oksana.dev.rtsoft.ru> References: <20081016171222.GA24812@oksana.dev.rtsoft.ru> <20081022014243.GA19362@oksana.dev.rtsoft.ru> <1224642497.7654.319.camel@pasglop> <200810212122.49121.david-b@pacbell.net> <20081022103641.GB24757@oksana.dev.rtsoft.ru> <20081022104606.GA510@oksana.dev.rtsoft.ru> Reply-To: avorontsov@ru.mvista.com Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1251 Return-path: Content-Disposition: inline In-Reply-To: <20081022104606.GA510@oksana.dev.rtsoft.ru> Sender: linux-kernel-owner@vger.kernel.org To: Grant Likely , David Brownell Cc: benh@kernel.crashing.org, linux-kernel@vger.kernel.org, linuxppc-dev@ozlabs.org, i2c@lm-sensors.org, David Miller List-Id: linux-i2c@vger.kernel.org On Wed, Oct 22, 2008 at 02:46:06PM +0400, Anton Vorontsov wrote: [...] > > > Like what I suggested: "chip-aware OF glue drivers". The relevant > > > bus code being the "of_platform_bus_type" infrastructure. > > > > > > Example: instead of Anton's patch #6 modifying the existing pca953x > > > driver, an of_pca953x driver that knows how to poke around in the OF > > > device attributes to (a) create the pca953x_platform_data, (b) call > > > i2c_register_board_info() to make that available later, and then > > > finally (c) vanish, since it's not needed any longer. > > > > Heh. You tell me my first approach: > > > > http://ozlabs.org/pipermail/linuxppc-dev/2008-May/056730.html (mmc_spi) > > > > The OF people didn't like the patch which was used to support this > > approach: > > http://ozlabs.org/pipermail/linuxppc-dev/2008-May/056728.html > > Though, I think I'll able to persuade Grant that two registration paths > are inevitable (i.e. for simple devices we should use > drivers/of/of_{i2c,spi}.c and for complex cases we'll have to have > another method of registration). Ok, here it is. I don't like this approach because: 1. It feels like an overhead to create an of_device for each i2c device that needs platform data. 2. We have to do ugly of_should_create_pdev() in the i2c code, and duplicate lists of supported devices. Could anybody convince me that this isn't a big deal? ;-) Otherwise I'll stick with this approach: http://lkml.org/lkml/2008/10/22/471 Thanks, -- Anton Vorontsov email: cbouatmailru@gmail.com irc://irc.freenode.net/bd2