From mboxrd@z Thu Jan  1 00:00:00 1970
From: Nicolas Pitre <nicolas.pitre@linaro.org>
Subject: Re: [PATCH] net/smsc911x: add device tree probe support
Date: Mon, 25 Jul 2011 22:28:05 -0400 (EDT)
Message-ID: <alpine.LFD.2.00.1107252222540.12766@xanadu.home>
References: <1311587040-8988-1-git-send-email-shawn.guo@linaro.org> <20110725213723.GI26735@ponder.secretlab.ca> <20110726010154.GG21641@S2100-06.ap.freescale.net> <alpine.LFD.2.00.1107252105561.12766@xanadu.home>
 <20110726013026.GH21641@S2100-06.ap.freescale.net>
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Cc: Grant Likely <grant.likely@secretlab.ca>, patches@linaro.org,
	netdev@vger.kernel.org, devicetree-discuss@lists.ozlabs.org,
	Steve Glendinning <steve.glendinning@smsc.com>,
	Shawn Guo <shawn.guo@linaro.org>,
	"David S. Miller" <davem@davemloft.net>,
	linux-arm-kernel@lists.infradead.org
To: Shawn Guo <shawn.guo@freescale.com>
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On Tue, 26 Jul 2011, Shawn Guo wrote:

> On Mon, Jul 25, 2011 at 09:16:40PM -0400, Nicolas Pitre wrote:
> > On Tue, 26 Jul 2011, Shawn Guo wrote:
> > 
> > > On Mon, Jul 25, 2011 at 03:37:23PM -0600, Grant Likely wrote:
> > > > On Mon, Jul 25, 2011 at 05:44:00PM +0800, Shawn Guo wrote:
> > > > > It adds device tree probe support for smsc911x driver.
> > > > > 
> > > > > Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
> > > > > Cc: Grant Likely <grant.likely@secretlab.ca>
> > > > > Cc: Steve Glendinning <steve.glendinning@smsc.com>
> > > > > Cc: David S. Miller <davem@davemloft.net>
> > > > > ---
> > > > >  Documentation/devicetree/bindings/net/smsc.txt |   34 +++++++
> > > > >  drivers/net/smsc911x.c                         |  123 +++++++++++++++++++-----
> > > > >  2 files changed, 132 insertions(+), 25 deletions(-)
> > > > >  create mode 100644 Documentation/devicetree/bindings/net/smsc.txt
> > > > > 
> > > > > diff --git a/Documentation/devicetree/bindings/net/smsc.txt b/Documentation/devicetree/bindings/net/smsc.txt
> > > > > new file mode 100644
> > > > > index 0000000..1920695
> > > > > --- /dev/null
> > > > > +++ b/Documentation/devicetree/bindings/net/smsc.txt
> > > > > @@ -0,0 +1,34 @@
> > > > > +* Smart Mixed-Signal Connectivity (SMSC) LAN Controller
> > > > > +
> > > > > +Required properties:
> > > > > +- compatible : Should be "smsc,lan<model>""smsc,lan"
> > > > 
> > > > Drop "smsc,lan".  That's far too generic.
> > > > 
> > > The following devices are supported by the driver.
> > > 
> > > LAN9115, LAN9116, LAN9117, LAN9118
> > > LAN9215, LAN9216, LAN9217, LAN9218
> > > LAN9210, LAN9211
> > > LAN9220, LAN9221
> > > 
> > > If we only keep specific <model> as the compatible, we will have a
> > > long match table which is actually used nowhere to distinguish the
> > > device.
> > > 
> > > So we need some level generic compatible to save the meaningless
> > > long match table.  What about: 
> > > 
> > > static const struct of_device_id smsc_dt_ids[] = {
> > >         { .compatible = "smsc,lan9", },
> > >         { /* sentinel */ }
> > > };
> > > 
> > > Or:
> > > 
> > > static const struct of_device_id smsc_dt_ids[] = {
> > >         { .compatible = "smsc,lan91", },
> > >         { .compatible = "smsc,lan92", },
> > >         { /* sentinel */ }
> > > };
> > 
> > None of this unambiguously distinguish the devices supported by this 
> > driver and the smc91x driver which supports LAN91C92, LAN91C94, 
> > LAN91C95, LAN91C96, LAN91C100, LAN91C110.
> > 
> So you suggest to make a long list to explicitly tell the device type
> that the driver supports?

I'm not suggesting anything.  :-)  I'm merely pointing out that the 
above .compatible = "smsc,lan9" or .compatible = "smsc,lan91" are too 
generic given that there is another driver with different devices to 
which they could also apply.


Nicolas

From mboxrd@z Thu Jan  1 00:00:00 1970
From: nicolas.pitre@linaro.org (Nicolas Pitre)
Date: Mon, 25 Jul 2011 22:28:05 -0400 (EDT)
Subject: [PATCH] net/smsc911x: add device tree probe support
In-Reply-To: <20110726013026.GH21641@S2100-06.ap.freescale.net>
References: <1311587040-8988-1-git-send-email-shawn.guo@linaro.org>
	<20110725213723.GI26735@ponder.secretlab.ca>
	<20110726010154.GG21641@S2100-06.ap.freescale.net>
	<alpine.LFD.2.00.1107252105561.12766@xanadu.home>
	<20110726013026.GH21641@S2100-06.ap.freescale.net>
Message-ID: <alpine.LFD.2.00.1107252222540.12766@xanadu.home>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

On Tue, 26 Jul 2011, Shawn Guo wrote:

> On Mon, Jul 25, 2011 at 09:16:40PM -0400, Nicolas Pitre wrote:
> > On Tue, 26 Jul 2011, Shawn Guo wrote:
> > 
> > > On Mon, Jul 25, 2011 at 03:37:23PM -0600, Grant Likely wrote:
> > > > On Mon, Jul 25, 2011 at 05:44:00PM +0800, Shawn Guo wrote:
> > > > > It adds device tree probe support for smsc911x driver.
> > > > > 
> > > > > Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
> > > > > Cc: Grant Likely <grant.likely@secretlab.ca>
> > > > > Cc: Steve Glendinning <steve.glendinning@smsc.com>
> > > > > Cc: David S. Miller <davem@davemloft.net>
> > > > > ---
> > > > >  Documentation/devicetree/bindings/net/smsc.txt |   34 +++++++
> > > > >  drivers/net/smsc911x.c                         |  123 +++++++++++++++++++-----
> > > > >  2 files changed, 132 insertions(+), 25 deletions(-)
> > > > >  create mode 100644 Documentation/devicetree/bindings/net/smsc.txt
> > > > > 
> > > > > diff --git a/Documentation/devicetree/bindings/net/smsc.txt b/Documentation/devicetree/bindings/net/smsc.txt
> > > > > new file mode 100644
> > > > > index 0000000..1920695
> > > > > --- /dev/null
> > > > > +++ b/Documentation/devicetree/bindings/net/smsc.txt
> > > > > @@ -0,0 +1,34 @@
> > > > > +* Smart Mixed-Signal Connectivity (SMSC) LAN Controller
> > > > > +
> > > > > +Required properties:
> > > > > +- compatible : Should be "smsc,lan<model>""smsc,lan"
> > > > 
> > > > Drop "smsc,lan".  That's far too generic.
> > > > 
> > > The following devices are supported by the driver.
> > > 
> > > LAN9115, LAN9116, LAN9117, LAN9118
> > > LAN9215, LAN9216, LAN9217, LAN9218
> > > LAN9210, LAN9211
> > > LAN9220, LAN9221
> > > 
> > > If we only keep specific <model> as the compatible, we will have a
> > > long match table which is actually used nowhere to distinguish the
> > > device.
> > > 
> > > So we need some level generic compatible to save the meaningless
> > > long match table.  What about: 
> > > 
> > > static const struct of_device_id smsc_dt_ids[] = {
> > >         { .compatible = "smsc,lan9", },
> > >         { /* sentinel */ }
> > > };
> > > 
> > > Or:
> > > 
> > > static const struct of_device_id smsc_dt_ids[] = {
> > >         { .compatible = "smsc,lan91", },
> > >         { .compatible = "smsc,lan92", },
> > >         { /* sentinel */ }
> > > };
> > 
> > None of this unambiguously distinguish the devices supported by this 
> > driver and the smc91x driver which supports LAN91C92, LAN91C94, 
> > LAN91C95, LAN91C96, LAN91C100, LAN91C110.
> > 
> So you suggest to make a long list to explicitly tell the device type
> that the driver supports?

I'm not suggesting anything.  :-)  I'm merely pointing out that the 
above .compatible = "smsc,lan9" or .compatible = "smsc,lan91" are too 
generic given that there is another driver with different devices to 
which they could also apply.


Nicolas