From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761877AbYD0RMT (ORCPT ); Sun, 27 Apr 2008 13:12:19 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754921AbYD0RMK (ORCPT ); Sun, 27 Apr 2008 13:12:10 -0400 Received: from www.tglx.de ([62.245.132.106]:33388 "EHLO www.tglx.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754606AbYD0RMJ (ORCPT ); Sun, 27 Apr 2008 13:12:09 -0400 Date: Sun, 27 Apr 2008 19:12:01 +0200 From: "Hans J. Koch" To: Uwe =?utf-8?Q?Kleine-K=C3=B6nig?= Cc: "Hans J. Koch" , Greg Kroah-Hartman , linux-kernel@vger.kernel.org Subject: Re: [PATCH 3/3] UIO: generic platform driver Message-ID: <20080427171201.GA3181@local> References: <20080422094708.GB27126@digi.com> <1208857977-29493-1-git-send-email-Uwe.Kleine-Koenig@digi.com> <1208857977-29493-2-git-send-email-Uwe.Kleine-Koenig@digi.com> <1208857977-29493-3-git-send-email-Uwe.Kleine-Koenig@digi.com> <20080423085629.GA16776@digi.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20080423085629.GA16776@digi.com> User-Agent: Mutt/1.5.17+20080114 (2008-01-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Apr 23, 2008 at 10:56:29AM +0200, Uwe Kleine-König wrote: > Hello, > > Uwe Kleine-König wrote: > > Signed-off-by: Uwe Kleine-König > > --- > > Hello, > > > > This is the former patch 4/4 after some discussion. > > > > Open issues: > > - clock name "uio" isn't considered good by Russell King > > I don't have a better suggestion > I added another branch[1] on my repo that doesn't have the dummy clk > patch and variant of this one that doesn't use the clk API. > > This way the clk API isn't needed anymore for my patch and the issue > about the clock name disappeard, too. Hi Uwe, sorry for the delay, I was away for a few days and had an awful lot of work when I came back. About your generic platform driver: I think we've got two choices, both of them are acceptable as far as I'm concerned: 1.) Use the clk API and make your driver depend on it. AFAICS, only ARM and PPC implement it right now. On some platforms, it will probably never be implemented. E.g. x86 doesn't have any clocks that could be controlled that way. It's probably only useful for SoCs. Advantages: People who need it get clk support for free, without having to write much code. Disadvantages: The generic platform driver is not available for all platforms. It might not be easy to implement the dependency in Kconfig in a way acceptable to all maintainers ;-) 2.) Don't use the clk API. I don't think we would lose much. Drivers could implement clk stuff in their board support. You could add some generic function pointers in struct uio_platdata that are called in open/release/probe/remove. That way, any platform specific stuff, including clk, could be handled. Advantages: The generic platform driver is available for all platforms, no need for dependencies in Kconfig. Disadvantages: People who need clk_* must write a lot of code within their board support file. Not nice and clean... I'm ready to accept 1.) or 2.), or even both of them (why can't we have two generic platform drivers?) As you are the author (and probably user) of this driver, please decide, and send a new patch for review. Thanks, Hans