Date:   Tue, 30 May 2017 08:22:44 +0200
From:   Karsten Merker <merker@...ian.org>
To:     Jagan Teki <jagannadh.teki@...il.com>
Cc:     Karsten Merker <merker@...ian.org>,
        Jagan Teki <jagan@...nedev.com>,
        Maxime Ripard <maxime.ripard@...e-electrons.com>,
        Chen-Yu Tsai <wens@...e.org>,
        Sean Wang <sean.wang@...iatek.com>,
        Icenowy Zheng <icenowy@...c.io>,
        Rob Herring <robh+dt@...nel.org>,
        Mark Rutland <mark.rutland@....com>,
        Catalin Marinas <catalin.marinas@....com>,
        Will Deacon <will.deacon@....com>,
        Michael Trimarchi <michael@...rulasolutions.com>,
        "linux-arm-kernel@...ts.infradead.org" 
        <linux-arm-kernel@...ts.infradead.org>, devicetree@...r.kernel.org,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        linux-sunxi <linux-sunxi@...glegroups.com>,
        Jagan Teki <jagan@...rulasolutions.com>
Subject: Re: [linux-sunxi] [PATCH 1/3] ARM: dts: sun7i-a20: Rename bananapi
 as bananapi m1

On Tue, May 30, 2017 at 10:00:49AM +0530, Jagan Teki wrote:
> On Tue, May 30, 2017 at 3:15 AM, Karsten Merker <merker@...ian.org> wrote:
> > On Mon, May 29, 2017 at 07:30:26PM +0000, Jagan Teki wrote:
> >> From: Jagan Teki <jagan@...rulasolutions.com>
> >>
> >> from BPI(BIPAI KEJI LIMITED) products the Bananapi board
> >> is named as 'Bananapi M1' and this is the starting
> >> bananapi board from M1 series.
> >>
> >> So rename dts and suffix 'M1' on model for the same,
> >> so-that next sequence on bananapi starts like M1 Plus, M2 and so..on
> >>
> >> Signed-off-by: Jagan Teki <jagan@...rulasolutions.com>
> >> ---
> >> Note: Bananapi BPI product site
> >> http://www.banana-pi.org/product.html
> >>
> >>  arch/arm/boot/dts/Makefile                  |   2 +-
> >>  arch/arm/boot/dts/sun7i-a20-bananapi-m1.dts | 286 ++++++++++++++++++++++++++++
> >>  arch/arm/boot/dts/sun7i-a20-bananapi.dts    | 286 ----------------------------
> >>  3 files changed, 287 insertions(+), 287 deletions(-)
> >>  create mode 100644 arch/arm/boot/dts/sun7i-a20-bananapi-m1.dts
> >>  delete mode 100644 arch/arm/boot/dts/sun7i-a20-bananapi.dts
> >>
> >> diff --git a/arch/arm/boot/dts/Makefile b/arch/arm/boot/dts/Makefile
> >> index 45c6e65..1b086f0 100644
> >> --- a/arch/arm/boot/dts/Makefile
> >> +++ b/arch/arm/boot/dts/Makefile
> >> @@ -851,7 +851,7 @@ dtb-$(CONFIG_MACH_SUN6I) += \
> >>       sun6i-a31s-sinovoip-bpi-m2.dtb \
> >>       sun6i-a31s-yones-toptech-bs1078-v2.dtb
> >>  dtb-$(CONFIG_MACH_SUN7I) += \
> >> -     sun7i-a20-bananapi.dtb \
> >> +     sun7i-a20-bananapi-m1.dtb \
> >>       sun7i-a20-bananapi-m1-plus.dtb \
> >>       sun7i-a20-bananapro.dtb \
> >>       sun7i-a20-cubieboard2.dtb \
> >> diff --git a/arch/arm/boot/dts/sun7i-a20-bananapi-m1.dts b/arch/arm/boot/dts/sun7i-a20-bananapi-m1.dts
> >> new file mode 100644
> >> index 0000000..8b97b89
> >> --- /dev/null
> >> +++ b/arch/arm/boot/dts/sun7i-a20-bananapi-m1.dts
> >> @@ -0,0 +1,286 @@
> >> +/*
> >> + * Copyright 2014 Hans de Goede <hdegoede@...hat.com>
> >> + *
> >> + * Hans de Goede <hdegoede@...hat.com>
> > [...]
> >> +/dts-v1/;
> >> +#include "sun7i-a20.dtsi"
> >> +#include "sunxi-common-regulators.dtsi"
> >> +
> >> +#include <dt-bindings/gpio/gpio.h>
> >> +#include <dt-bindings/interrupt-controller/irq.h>
> >> +
> >> +/ {
> >> +     model = "LeMaker Banana Pi M1";
> >> +     compatible = "lemaker,bananapi", "allwinner,sun7i-a20";
> > [...]
> >> diff --git a/arch/arm/boot/dts/sun7i-a20-bananapi.dts b/arch/arm/boot/dts/sun7i-a20-bananapi.dts
> >> deleted file mode 100644
> >> index ed2f35a..0000000
> >> --- a/arch/arm/boot/dts/sun7i-a20-bananapi.dts
> >> +++ /dev/null
> >
> > NACK!
> >
> > Please neither rename the dts nor change the model string. Such a
> > change would make newer kernels unusable on many existing
> > installations without manual fixups by the end user.  Linux
> > distributions use databases with model-specific setup information
> > (such as the dtb file name, the platform-specific bootscript to
> > use, usable kernel flavours (lpae or non-lpae), etc.) on kernel
> > installations and kernel upgrades, and those use the model string
> > as their key for finding the relevant information.  If you change
> > either the dts file name or the model string inside the dts,
> > you'll effectively break the proper installation of newer kernel
> > versions on existing end user systems.
> 
> I understand your concerns about distribution change, but with new
> change in 'bananapi' brand owned by BIPAI KEJI(BPI) the model must
> need to update and this is not technically as Bananapi board it is
> Bananapi  M1 [1]
> 
> These are generic changes based on the hardware vendor info.
> 
> [1] http://www.banana-pi.org/m1.html

Hello Jagan,

I have to disagree here. Whatever BIPAI KEJI(BPI) chooses to name
their products today or in the future doesn't change history. 
The "original" Banana Pi was sold under the LeMaker brand and it
was named "Banana Pi" and not "Banana Pi M1".  The fact that
LeMaker has stopped selling their Banana Pi board and BIPAI
KEJI(BPI) (a different company than LeMaker!) now sells a board
that is compatible to the original "LeMaker Banana Pi" under the
name "Banana Pi M1" (and not "LeMaker Banana Pi M1" as you claim
in your modified dts) doesn't matter at all for an existing dts
and is in no way a valid reason to make an incompatible change
that breaks existing systems.

If you wanted to add a new (technically identical) dts with a
different model string under a new dts file name and keep the
existing one unchanged, I would find that unneccessary but at
least acceptable insofar as it wouldn't break existing end user
systems, but breaking existing systems in the wild is clearly
unacceptable.  I assume that the kernel dts maintainers would
probably still object to such an addition as it is unneccessary
from a purely technical point of view if the boards are 100%
compatible, but that would of course be their decision to make.

Regards,
Karsten
-- 
Gem. Par. 28 Abs. 4 Bundesdatenschutzgesetz widerspreche ich der Nutzung
sowie der Weitergabe meiner personenbezogenen Daten für Zwecke der
Werbung sowie der Markt- oder Meinungsforschung.

Powered by blists - more mailing lists