From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chaotian Jing Subject: Re: [PATCH 01/12] mmc: dt-bindings: update Mediatek MMC bindings Date: Wed, 27 Sep 2017 09:18:20 +0800 Message-ID: <1506475100.19851.9.camel@mhfsdcap03> References: <1505207272-16983-1-git-send-email-chaotian.jing@mediatek.com> <1505207272-16983-2-git-send-email-chaotian.jing@mediatek.com> <20170913141026.43oh4n4foipmahsk@rob-hp-laptop> <1505355021.8308.4.camel@mhfsdcap03> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org To: Ulf Hansson Cc: Rob Herring , Mark Rutland , Matthias Brugger , Catalin Marinas , Will Deacon , yong mao , Linus Walleij , Javier Martinez Canillas , Heiner Kallweit , Phong LE , "linux-mmc@vger.kernel.org" , "devicetree@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , linux-mediatek@lists.infradead.org, "linux-kernel@vger.kernel.org" , srv_heupstream List-Id: devicetree@vger.kernel.org On Wed, 2017-09-27 at 00:33 +0200, Ulf Hansson wrote: > On 14 September 2017 at 04:10, Chaotian Jing wrote: > > On Wed, 2017-09-13 at 09:10 -0500, Rob Herring wrote: > >> On Tue, Sep 12, 2017 at 05:07:41PM +0800, Chaotian Jing wrote: > >> > Change the comptiable for support of multi-platform > >> > Add description for reg > >> > Add description for source_cg > >> > Add description for mediatek,latch-ck > >> > >> This is at least the 3rd patch with exactly the same vague subject. > >> Please make the subject somewhat unique. > >> > > Thx, will change the subject at next version > >> > > >> > Signed-off-by: Chaotian Jing > >> > --- > >> > Documentation/devicetree/bindings/mmc/mtk-sd.txt | 13 ++++++++++--- > >> > 1 file changed, 10 insertions(+), 3 deletions(-) > >> > > >> > diff --git a/Documentation/devicetree/bindings/mmc/mtk-sd.txt b/Documentation/devicetree/bindings/mmc/mtk-sd.txt > >> > index 4182ea3..405cd06 100644 > >> > --- a/Documentation/devicetree/bindings/mmc/mtk-sd.txt > >> > +++ b/Documentation/devicetree/bindings/mmc/mtk-sd.txt > >> > @@ -7,10 +7,15 @@ This file documents differences between the core properties in mmc.txt > >> > and the properties used by the msdc driver. > >> > > >> > Required properties: > >> > -- compatible: Should be "mediatek,mt8173-mmc","mediatek,mt8135-mmc" > >> > +- compatible: value should be either of the following. > >> > + "mediatek,mt8135-mmc": for mmc host ip compatible with mt8135 > >> > + "mediatek,mt8173-mmc": for mmc host ip compatible with mt8173 > >> > + "mediatek,mt2701-mmc": for mmc host ip compatible with mt2701 > >> > + "mediatek,mt2712-mmc": for mmc host ip compatible with mt2712 > >> > +- reg: physical base address of the controller and length > >> > - interrupts: Should contain MSDC interrupt number > >> > -- clocks: MSDC source clock, HCLK > >> > -- clock-names: "source", "hclk" > >> > +- clocks: MSDC source clock, HCLK, source_cg > >> > +- clock-names: "source", "hclk", "source_cg" > >> > >> All chips support source_cg? That's not backwards compatible for > >> existing compatible strings if the driver requires it. > > Not all chips support source_cg, for chips which do not support > > source_cg, no need source_cg here, and the driver will parse it > > to know if current chip support it. > > In such case you must not add add a required binding for it. I think > that is what Rob is trying to point out for you. > > [...] > > Kind regards > Uffe The source_cg is required(MUST) at MT2712 and future SoCs, but not required(do not have it) at previous SoCs, so that put it at required properties, let the driver to handle it.