From mboxrd@z Thu Jan 1 00:00:00 1970 From: loic pallardy Subject: Re: [STLinux Kernel] [PATCH 02/11] drivers: clk: st: Add clock propagation for audio clocks Date: Thu, 26 May 2016 15:05:10 +0200 Message-ID: <5746F486.602@st.com> References: <1463560892-7209-1-git-send-email-gabriel.fernandez@linaro.org> <1463560892-7209-3-git-send-email-gabriel.fernandez@linaro.org> <20160525172409.GA27913@rob-hp-laptop> Mime-Version: 1.0 Content-Type: text/plain; charset="windows-1252"; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org To: Rob Herring , Gabriel Fernandez Cc: Mark Rutland , "kernel@stlinux.com" , Geert Uytterhoeven , Michael Turquette , "linux-kernel@vger.kernel.org" , Andrzej Hajda , linux-clk , Benjamin GAIGNARD , Olivier Bideau , Russell King , Thierry Reding , Sebastian Hesselbarth , "devicetree@vger.kernel.org" , Arnd Bergmann , Ian Campbell , Vincent ABRIOU , "linux-arm-kernel@lists.infradead.org" , Srinivas Kandagatla , Stephen Boyd , Ku List-Id: devicetree@vger.kernel.org On 05/26/2016 02:46 PM, Rob Herring wrote: > On Thu, May 26, 2016 at 4:49 AM, Gabriel Fernandez > wrote: >> On 25 May 2016 at 19:24, Rob Herring wrote: >>> >>> On Wed, May 18, 2016 at 10:41:23AM +0200, Gabriel Fernandez wrote: >>>> This patch allows fine tuning of the quads FS for audio clocks >>>> accuracy. >>>> >>>> Signed-off-by: Olivier Bideau >>>> Signed-off-by: Gabriel Fernandez >>>> --- >>>> .../devicetree/bindings/clock/st/st,flexgen.txt | 1 + >>>> drivers/clk/st/clk-flexgen.c | 24 ++++++++++++++++++++++ >>>> 2 files changed, 25 insertions(+) >>>> >>>> diff --git a/Documentation/devicetree/bindings/clock/st/st,flexgen.txt b/Documentation/devicetree/bindings/clock/st/st,flexgen.txt >>>> index b7ee5c7..15b33c7 100644 >>>> --- a/Documentation/devicetree/bindings/clock/st/st,flexgen.txt >>>> +++ b/Documentation/devicetree/bindings/clock/st/st,flexgen.txt >>>> @@ -60,6 +60,7 @@ This binding uses the common clock binding[2]. >>>> Required properties: >>>> - compatible : shall be: >>>> "st,flexgen" >>>> + "st,stih407-clkgend0", "st,flexgen" (enable clock propagation on parent) >>> >>> What do "d0" and "d2" refer to? >>> >>> This seems to indicate you have too much clock detail in the DT (with >>> individual clocks described) or not enough with genericish compatible >>> strings. What happens for the mext clock you need to adjust the flags >>> on? You should be able to make these adjustments without DT updates. >>> Perhaps you need a wider fixing of clock compatible strings. >>> >>> Rob >> >> Sorry i sent my response in html... >> >> Hi Rob, >> >> Thanks for reviewing. >> >> Can i remove >> " >> st,stih407-clkgend0" & " >> st,stih407-clkgend2" compatible strings and add proprieties instead ? >> I only need to activate 2 features and then we can keep generic >> compatible strings. > Hi Rob, > That is no different and suffers the same point I raised. It requires > updating the DT for any clock configuration change or enhancement. > Agree with you, DT update is needed as soon as a clock configuration should be changed. This is due to STiH clock driver design based on DT description of SoC clock tree. This clock driver was accepted 2 years ago. At the time being there was discussion about clock tree description location: driver or DT. Bad choice was done for this driver... If we decide to redesign STiH clock driver using in-driver clock tree description, this will modify STiH clock DT nodes description and so break DT backward compatibility. What's from your pov the best option? Regards, Loic > Rob > > _______________________________________________ > Kernel mailing list > Kernel@stlinux.com > http://www.stlinux.com/mailman/listinfo/kernel >