Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759644Ab2EVCPW (ORCPT ); Mon, 21 May 2012 22:15:22 -0400 Received: from mail-pz0-f46.google.com ([209.85.210.46]:53522 "EHLO mail-pz0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758698Ab2EVCPU (ORCPT ); Mon, 21 May 2012 22:15:20 -0400 Date: Tue, 22 May 2012 10:15:37 +0800 From: Shawn Guo To: Rob Herring Cc: Shawn Guo , Mike Turquette , Grant Likely , "arm@kernel.org" , "linux-arm-kernel@lists.infradead.org" , "linux-kernel@vger.kernel.org" Subject: Re: [GIT PULL] DT clk binding support Message-ID: <20120522021535.GG8140@S2101-09.ap.freescale.net> References: <4FB80F32.5090309@gmail.com> <20120520030653.GB5810@S2100-06.ap.freescale.net> <4FB9A5E7.2070000@gmail.com> <20120521064901.GE8140@S2101-09.ap.freescale.net> <4FBA89E3.7010106@gmail.com> <20120521232616.GF8140@S2101-09.ap.freescale.net> <4FBAD545.7060803@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4FBAD545.7060803@gmail.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2433 Lines: 46 On Mon, May 21, 2012 at 06:52:37PM -0500, Rob Herring wrote: > As Grant states: "This proposed binding is only about one thing: > attaching clock providers to clock consumers." This means you have to > have at least a single provider and a single consumer defined in the DT. > I just read through Grant's comments over again. I agree with the statement which implicitly requires the clk provider defined in DT. However, for some case, this provider in DT is just a skeleton which is backed by clock driver where the provider is actually defined. Looking at Grant's comment below, the second option is also to match the clock in driver just using name. The only difference to my proposal is the name here is given by the argument of phandle pointing to that skeleton provider node. I'm fine with that. So go ahead with your bindings. Regards, Shawn On Wed, Nov 16, 2011 at 03:12:50PM -0700, Grant Likely wrote: > I'm really not convinced that it is a good idea to break out the > entire clock tree into one node per struct clk. To begin with, that > looks to be very centric around the current 'struct clk' Linux > abstraction, which is potentially in flux. Also, looking at Sascha's > initial RFC for describing the clock tree, I see cases where it looks > like a clock nexus node really makes sense. For instance, the > 'divider-ipg 0x53fd4014' node which has a list of child nodes > which merely provide a register offset and shift value > (reg=0x53fd4068..0x53fd4084, shift=0x0..0xf). It would be natural to > instead encode that as part of the clock reference, or map it directly > from the clock reference (ie, assign names to each of the clocks, and > let the clock provider driver match up the name to the reg offset & > shift values). > > I had originally thought that it would be better to use names directly > for references to clocks (ie. clock = ,"name") , but after > actually playing with it and looking at the existing DT conventions, > I've reverted to cell values for the arguments and a separate set of > clock-{input,output}-name properties for attaching meaningful names, > just like we decided to do for assigning names to 'reg' properties. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/