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Date:   Sat, 15 Jan 2022 00:20:46 +0100
From:   Pali =?utf-8?B?Um9ow6Fy?= <pali@kernel.org>
To:     Stephen Boyd <sboyd@kernel.org>
Cc:     Gregory CLEMENT <gregory.clement@bootlin.com>,
        Michael Turquette <mturquette@baylibre.com>,
        Rob Herring <robh+dt@kernel.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Andrew Lunn <andrew@lunn.ch>,
        Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>,
        Vladimir Vid <vladimir.vid@sartura.hr>,
        Marek =?utf-8?B?QmVow7pu?= <kabel@kernel.org>,
        linux-clk@vger.kernel.org, linux-serial@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        devicetree@vger.kernel.org
Subject: Re: [PATCH v7 0/6] serial: mvebu-uart: Support for higher baudrates
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On Friday 14 January 2022 15:16:55 Stephen Boyd wrote:
> Quoting Pali Rohár (2022-01-14 15:05:49)
> > On Friday 14 January 2022 14:56:58 Stephen Boyd wrote:
> > > 
> > > If we're adding new support why can't we break with backwards
> > > compatibility for the binding and do it a different way?
> > 
> > Because DTS are backwards compatible. I was told more times that kernel
> > drivers should work correctly with older DTS files. On some boards are
> > DTB files provided by bootloader and they do not use in-kernel DTS
> > files.
> 
> I'm not suggesting to break the kernel driver when used with older DTBs.
> New features are fair game to change the compatible string and do
> something different. If the user wants the new feature they update their
> DTB. We shouldn't be constrained by backwards compatibility here.

And what do you suggest to do? Separate UART0 and UART1 nodes are still
needed because as Mark wrote stdin-path and stdout-patch could be
different.