From mboxrd@z Thu Jan  1 00:00:00 1970
From: LW@KARO-electronics.de (=?utf-8?Q?Lothar_Wa=C3=9Fmann?=)
Date: Thu, 28 Jun 2012 14:24:32 +0200
Subject: [PATCH v2 2/2] net: flexcan: add transceiver switch gpios support
In-Reply-To: <20120628121302.GI22990@S2101-09.ap.freescale.net>
References: <1340853701-4488-1-git-send-email-shawn.guo@linaro.org>
 <1340853701-4488-3-git-send-email-shawn.guo@linaro.org>
 <4FEC329C.7070004@pengutronix.de>
 <20120628112111.GC22990@S2101-09.ap.freescale.net>
 <4FEC400F.8010506@pengutronix.de>
 <20120628114108.GD22990@S2101-09.ap.freescale.net>
 <20460.18717.17688.965250@ipc1.ka-ro>
 <20120628121302.GI22990@S2101-09.ap.freescale.net>
Message-ID: <20460.19712.158996.397146@ipc1.ka-ro>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

Hi,

Shawn Guo writes:
> On Thu, Jun 28, 2012 at 02:07:57PM +0200, Lothar Wa?mann wrote:
> > Hi,
> > 
> > Shawn Guo writes:
> > > On Thu, Jun 28, 2012 at 01:29:19PM +0200, Marc Kleine-Budde wrote:
> > > > I mean which name is more precise, do these gpio enable/standy a "phy"
> > > > or a "transceiver". For example:
> > > > http://www.nxp.com/documents/application_note/AN00094.pdf, this document
> > > > says: TJA1041/1041A high speed CAN transceiver.
> > > > 
> > > Isn't term "phy" (physical interface) generally meant to be the same
> > > thing as "transceiver"?  I just happened to like the shorter one as
> > > what Hui did in his patch.
> > > 
> > > But it does not really matter to me, will change the name since you
> > > care about it.
> > > 
> > A transceiver is just a dumb piece of hardware, while a PHY contains
> > some intelligence of its own.
> > 
> Then, it sounds more like a PHY than transceiver, since it's an IC
> chip with some control over it.
> 
The 'I' in 'IC' does not stand for 'intelligent', but for
'integrated'. ;)
A can transceiver is usually merely a switchable buffer. There are no
registers to configure it or an internal processor that does some
magic.


Lothar Wa?mann
-- 
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