Re: [PATCH v4 2/9] dt-bindings: mtd: ingenic: Change 'BCH' to 'ECC' in documentation

From: Miquel Raynal <miquel.raynal@bootlin.com>
To: Paul Cercueil <paul@crapouillou.net>
Cc: David Woodhouse <dwmw2@infradead.org>,
	Brian Norris <computersforpeace@gmail.com>,
	Boris Brezillon <bbrezillon@kernel.org>,
	Marek Vasut <marek.vasut@gmail.com>,
	Richard Weinberger <richard@nod.at>,
	Rob Herring <robh+dt@kernel.org>,
	Mark Rutland <mark.rutland@arm.com>,
	Harvey Hunt <harveyhuntnexus@gmail.com>,
	linux-mtd@lists.infradead.org, devicetree@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH v4 2/9] dt-bindings: mtd: ingenic: Change 'BCH' to 'ECC' in documentation
Date: Mon, 4 Mar 2019 19:58:52 +0100	[thread overview]
Message-ID: <20190304195852.45c056f6@xps13> (raw)
In-Reply-To: <1551723830.4932.3@crapouillou.net>

Hi Paul,

Paul Cercueil <paul@crapouillou.net> wrote on Mon, 04 Mar 2019 19:23:50
+0100:

> On Mon, Mar 4, 2019 at 10:50 AM, Miquel Raynal <miquel.raynal@bootlin.com> wrote:
> > Hi Paul,
> > 
> > Paul Cercueil <paul@crapouillou.net <mailto:paul@crapouillou.net>> > wrote on Sat,  9 Feb 2019 16:22:58
> > -0300:
> >   
> >>  The JZ4740 ECC hardware is not BCH but Reed-Solomon, so it makes >> more
> >>  sense to use the more generic ECC term.  
> >> >>  Signed-off-by: Paul Cercueil <paul@crapouillou.net >> <mailto:paul@crapouillou.net>>  
> >>  ---  
> >> >>  Changes:
> >> >>  v3: New patch
> >> >>  v4: No change
> >> >>   .../devicetree/bindings/mtd/ingenic,jz4780-nand.txt    | 18 >> +++++++++---------  
> >>   1 file changed, 9 insertions(+), 9 deletions(-)  
> >> >>  diff --git >> a/Documentation/devicetree/bindings/mtd/ingenic,jz4780-nand.txt >> b/Documentation/devicetree/bindings/mtd/ingenic,jz4780-nand.txt  
> >>  index a5b940f18bf6..5a45cc54f46d 100644
> >>  --- a/Documentation/devicetree/bindings/mtd/ingenic,jz4780-nand.txt
> >>  +++ b/Documentation/devicetree/bindings/mtd/ingenic,jz4780-nand.txt
> >>  @@ -1,4 +1,4 @@
> >>  -* Ingenic JZ4780 NAND/BCH
> >>  +* Ingenic JZ4780 NAND/ECC  
> >> >>   This file documents the device tree bindings for NAND flash >> devices on the  
> >>   JZ4780. NAND devices are connected to the NEMC controller >> (described in
> >>  @@ -14,10 +14,10 @@ Required NAND controller device properties:
> >>     an offset of 0 and a size of 0x1000000 (i.e. the whole NEMC >> bank).  
> >> >>   Optional NAND controller device properties:  
> >>  -- ingenic,bch-controller: To make use of the hardware BCH >> controller, this
> >>  -  property must contain a phandle for the BCH controller node. The >> required
> >>  +- ingenic,bch-controller: To make use of the hardware ECC >> controller, this
> >>  +  property must contain a phandle for the ECC controller node. The >> required  
> > 
> > I think there is already a 'ecc-engine' property used by MTK and Atmel
> > NAND controllers to point to the ECC engine block. Please use this
> > property instead of the ingenic specific one.  
> 
> ingenic,bch-controller is already in the devicetree ABI. I can't change it now...

Oh, right...

Well, same thing as before, maybe you can change it and keep the driver
backward compatible? I don't want new DT to use this property because
it is not generic and we must have a way from the core to find the ECC
engine handle when the controller does not embed one itself (thus, the
ecc-engine property which is around for quite some time already).

Thanks,
Miquèl