Message-ID: <1506650162.19851.12.camel@mhfsdcap03>
Subject: Re: [PATCH 01/12] mmc: dt-bindings: update Mediatek MMC bindings
From: Chaotian Jing <chaotian.jing@mediatek.com>
To: Ulf Hansson <ulf.hansson@linaro.org>
CC: Rob Herring <robh@kernel.org>, Mark Rutland <mark.rutland@arm.com>,
        Matthias Brugger <matthias.bgg@gmail.com>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will.deacon@arm.com>, yong mao <yong.mao@mediatek.com>,
        Linus Walleij <linus.walleij@linaro.org>,
        "Javier Martinez Canillas" <javier@osg.samsung.com>,
        Heiner Kallweit <hkallweit1@gmail.com>, Phong LE <ple@baylibre.com>,
        "linux-mmc@vger.kernel.org" <linux-mmc@vger.kernel.org>,
        "devicetree@vger.kernel.org" <devicetree@vger.kernel.org>,
        "linux-arm-kernel@lists.infradead.org" 
        <linux-arm-kernel@lists.infradead.org>,
        <linux-mediatek@lists.infradead.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        srv_heupstream <srv_heupstream@mediatek.com>
Date: Fri, 29 Sep 2017 09:56:02 +0800
In-Reply-To: <1506475100.19851.9.camel@mhfsdcap03>
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         <1505207272-16983-2-git-send-email-chaotian.jing@mediatek.com>
         <20170913141026.43oh4n4foipmahsk@rob-hp-laptop>
         <1505355021.8308.4.camel@mhfsdcap03>
         <CAPDyKFrUe-0hEsxVRQSZvujcXY8WrR6m-0DMW=VwDDLvz7Lexw@mail.gmail.com>
         <1506475100.19851.9.camel@mhfsdcap03>
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On Wed, 2017-09-27 at 09:18 +0800, Chaotian Jing wrote:
> On Wed, 2017-09-27 at 00:33 +0200, Ulf Hansson wrote:
> > On 14 September 2017 at 04:10, Chaotian Jing <chaotian.jing@mediatek.com> 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 <chaotian.jing@mediatek.com>
> > >> > ---
> > >> >  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.

Any other comments about it ? still must not add a required binding for
it ? if add a optional binding for it, how to add it ? as cannot
duplicate "clocks" & "clock-names" in one node.