From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Warren Subject: Re: [PATCH v4 3/5] clk: dt: binding for basic multiplexer clock Date: Wed, 04 Sep 2013 12:36:47 -0600 Message-ID: <52277DBF.7080104@wwwdotorg.org> References: <1377150793-27864-1-git-send-email-mturquette@linaro.org> <1377150793-27864-4-git-send-email-mturquette@linaro.org> <2A930389-012E-45C3-93EB-6B4A41DB2EF5@codeaurora.org> <20130829011425.8231.78802@quantum> <39BAF1F8-41AD-4667-BF76-22BDF709415A@codeaurora.org> <20130830203334.10934.10011@quantum> <522110AA.7040700@wwwdotorg.org> <20130903232219.10934.67434@quantum> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20130903232219.10934.67434@quantum> Sender: linux-kernel-owner@vger.kernel.org To: Mike Turquette Cc: Kumar Gala , devicetree@vger.kernel.org, =?UTF-8?B?SGVpa28gU3TDvGJuZXI=?= , Stephen Boyd , linux-kernel@vger.kernel.org, Tero Kristo , Haojian Zhuang , Matt Sealey , linux-arm-kernel@lists.infradead.org List-Id: devicetree@vger.kernel.org On 09/03/2013 05:22 PM, Mike Turquette wrote: > Quoting Stephen Warren (2013-08-30 14:37:46) >> On 08/30/2013 02:33 PM, Mike Turquette wrote: ... >>> The clock _data_ seems to always have some churn to it. Moving it out to >>> DT reduces that churn from Linux. My concern above is not about kernel >>> data size. >> >> That sounds like the opposite of what we should be doing. >> >> It's fine for kernel code/data to change; that's a natural part of >> development. Obviously, we should minimize churn, through thorough >> review, domain knowledge, etc. > > And with the "clock mapping" style bindings we'll end up changing both > the DT binding definition and the kernel. Not great. What's a "clock mapping" style binding? I guess that means the style where you have a single DT node that provides multiple clocks, rather than one DT node per clock? If the kernel driver changes its internal data, I don't see why that would have any impact at all on the DT binding definition. We should be able to use one DT binding definition with arbitrary drivers. > And I'll respond to your points below but the whole "relocate the > problem to DT" argument is simply not my main point. What I want to do > is increase the usefulness of DT by allowing register-level details into > the binding which can Can you expand upon why a DT that encodes register-level details is more useful? I can't see why there would be any difference in usefulness.