From mboxrd@z Thu Jan  1 00:00:00 1970
From: Dong Aisheng <b29396@freescale.com>
Subject: Re: [PATCH 1/3] can: m_can: add Bosch M_CAN controller support
Date: Thu, 3 Jul 2014 11:48:41 +0800
Message-ID: <20140703034839.GA20450@shlinux1.ap.freescale.net>
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 <53ADB1E8.1030504@hartkopp.net>
 <20140630082622.GB25689@shlinux1.ap.freescale.net>
 <53B4473B.2050003@hartkopp.net> <53B459C3.6070807@pengutronix.de>
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To: Marc Kleine-Budde <mkl@pengutronix.de>
Cc: Oliver Hartkopp <socketcan@hartkopp.net>, linux-can@vger.kernel.org, wg@grandegger.com, devicetree@vger.kernel.org
List-Id: devicetree@vger.kernel.org

On Wed, Jul 02, 2014 at 09:13:07PM +0200, Marc Kleine-Budde wrote:
> On 07/02/2014 07:54 PM, Oliver Hartkopp wrote:
> > I'm not really familiar with the naming concept in device trees.
> > 
> > What is your opinion about the remarks below?
> 
> The entries in the DT, at least on freescale baords, follow the naming
> scheme of the reference manual. E.g. on the mx25 it's can1 and can2:
> 
>     can1: can@43f88000 { ... }
>     can2: can@43f8c000 { ... }
> 
> And on the mx28, its:
> 
>     can0: can@80032000 { ... }
>     can1: can@80034000 { ... }
> 
> Because the imx25 datasheet uses a "1" based counting scheme, while the
> imx28 uses a "0" based one.
> 
> So it's best practise to follow the naming and numbering scheme of the
> hardware reference manual.....and if you have access to the
> documentation of the m_can core, use clock names of the m_can core for
> the clock-names property.
> 

Based on my knowledge, device tree allows define phandle name according to
the real device name of HW according spec while the device node name should
be general(e.g can@80032000 rather than flexcan@80032000).
For imx6sx, there are already following entries in
arch/arm/boot/dts/imx6sx.dtsi
flexcan1: can@02090000 {...}
flexcan2: can@02094000 {...}
So i'd prefer to define as:
m_can1: canfd@020e8000 {...}
m_can2: canfd@020f0000 {...}


One problem is there're can alias already.
aliases {
	can0 = &flexcan1;
	can1 = &flexcan2;
	...
}
I'm not sure adding can2&can3 for mcan is properly:
aliases {
	can0 = &flexcan1;
	can1 = &flexcan2;
	can2 = &m_can1;
	can3 = &m_can2;
	...
}
Since the m_can driver does not need to use aliases,
so i will not add them.

Regards
Dong Aisheng

> Marc
> -- 
> Pengutronix e.K.                  | Marc Klein-Budde           |
> Industrial Linux Solutions        | Phone: +49-231-2826-924     |
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>