From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from gate.crashing.org (gate.crashing.org [63.228.1.57]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 7D12BB7D5C for ; Thu, 29 Apr 2010 10:43:08 +1000 (EST) Subject: Re: [alsa-devel] [PATCH 1/2] powerpc: add platform registration for ALSA SoC drivers From: Benjamin Herrenschmidt To: Mark Brown In-Reply-To: <20100428130037.GF31400@opensource.wolfsonmicro.com> References: <1272314980-23679-1-git-send-email-timur@freescale.com> <1272350168.24542.6.camel@pasglop> <1272355624.3204.52.camel@odin> <4BD74D0C.40303@freescale.com> <20100427205924.GC15083@opensource.wolfsonmicro.com> <1272428729.24542.70.camel@pasglop> <20100428130037.GF31400@opensource.wolfsonmicro.com> Content-Type: text/plain; charset="UTF-8" Date: Thu, 29 Apr 2010 10:42:56 +1000 Message-ID: <1272501776.24542.131.camel@pasglop> Mime-Version: 1.0 Cc: alsa-devel@alsa-project.org, kumar.gala@freescale.com, linuxppc-dev@ozlabs.org, Timur Tabi , Liam Girdwood List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Wed, 2010-04-28 at 14:00 +0100, Mark Brown wrote: > > The whole thing is a matter of common sense and a bit of taste :-) > > The impression that has been created in the past is that there are > inflexible device tree rules which can't be varied. I'm a bit sad this is how things have been perceived since that's clearly not the policy I've applied to the powerpc architecture. Or rather, there are -some- inflexible rules yes, which are to: - Have a device-tree :-) - Have a /compatible property at the toplevel to identify your board - Have the /cpus nodes for representing the CPUs. That's pretty much the only absolute requirements from a code perspective. Now I -do- require people to also have nodes for things like PCI host bridge, since that allows using a ton of existing code for handling most aspects of PCI, and I -do- complain if people just hard wire platform devices everywhere or interrupt numbers without even trying to consider using the device-tree appropriately. However, I've always been against the one-bsp-fits-all approach, and it's always been my clear policy that there should be a per-machine .c file. I did bend when folks pushed the "simple" platform but with the understanding that it must contain an -explicit- list of boards it supports. You'll also notice that all of my virtual interrupt handling stuff is such that you -can- use it without device-tree nodes, the DT just makes it easier. Same goes with PCI devices (only the PHB requires a DT node at this stage) etc... Cheers, Ben.