From: Fabio Baltieri <fabio.baltieri@gmail.com>
To: Oliver Hartkopp <socketcan@hartkopp.net>,
Marc Kleine-Budde <mkl@pengutronix.de>,
linux-can@vger.kernel.org, linux-kernel@vger.kernel.org,
Wolfgang Grandegger <wg@grandegger.com>
Subject: Re: [PATCH can-next v6] can: add tx/rx LED trigger support
Date: Tue, 4 Sep 2012 22:15:53 +0200 [thread overview]
Message-ID: <20120904201553.GA29478@gmail.com> (raw)
In-Reply-To: <20120904071128.GB416@vandijck-laurijssen.be>
On Tue, Sep 04, 2012 at 09:11:28AM +0200, Kurt Van Dijck wrote:
> On Mon, Sep 03, 2012 at 10:54:49PM +0200, Oliver Hartkopp wrote:
> > On 03.09.2012 20:29, Fabio Baltieri wrote:
> >
> > > On Mon, Sep 03, 2012 at 08:13:35PM +0200, Kurt Van Dijck wrote:
> > >> On Mon, Sep 03, 2012 at 02:40:39PM +0200, Marc Kleine-Budde wrote:
> > >>> The net->ifindex is unique. But it's only an integer. Usually can0 has a
> > >>> ifindex != 0, so a simple can%d is contra productive here.
> > >>>
> > >>> Some pointers to related code:
> > >>> http://lxr.free-electrons.com/source/drivers/base/core.c#L1847
> > >>> http://lxr.free-electrons.com/source/drivers/base/core.c#L73
> > >>> http://lxr.free-electrons.com/source/include/linux/device.h#L695
> > >>>
> > >>> comments?
> > >
> > > That would probabily makes really hard to choose the right
> > > default_trigger for led devices to get to the appropriate CAN LED in
> > > embedded systems, as trigger name would depend from other network
> > > devices and probing order (correct me if I'm wrong).
> > >
> > > Something with device name would probaily be more appropriate here.
> > >
> > >>
> > >> a very recent idea: something with netdevice notifiers and NETDEV_CHANGENAME ...
> > >> http://lxr.free-electrons.com/source/net/core/dev.c#L1030
> > >>
> > >> you could: rename the trigger, or if we think it's usefull,
> > >> block the netdev rename when its triggers are in use.
> > >
> > > Blocking the rename looks overkill to me,
>
> renaming a netdev _after_ first attaching led triggers looks stupid to me
> anyway.
>
> > > what about using device name
> > > with an optional "port id" appended to it? Sounds simpler...
> >
> >
> > The name of the device can only be changed when the interface is down.
> > Is it possible to put some scripting around it to detach and attach the leds
> > to the interfaces on ifup/ifdown triggers?
>
> Are the led triggers available for using while the netdev is down then?
Sure! On embedded systems triggers are usually attached to actual LEDs
at probe time using default_trigger field of struct led_classdev, and
that can be specified both in machine files or in device tree.
See
http://lxr.free-electrons.com/source/arch/powerpc/boot/dts/mpc8315erdb.dts#L477
http://lxr.free-electrons.com/source/arch/arm/mach-pxa/tosa.c#L576
that's why the trigger name should be predictable, at least at
boot/probe time.
The actual CAN LED trigger also reflects the actual state of the
interface (off if down, on if up, blink on activity).
Fabio
next prev parent reply other threads:[~2012-09-04 20:15 UTC|newest]
Thread overview: 67+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-07-30 19:20 [PATCH can-next v3 1/2] can: add tx/rx LED trigger support Fabio Baltieri
2012-07-30 19:20 ` [PATCH can-next v3 2/2] can: flexcan: add " Fabio Baltieri
2012-07-30 21:17 ` [PATCH can-next v3 1/2] can: add tx/rx " Marc Kleine-Budde
2012-07-31 6:57 ` Fabio Baltieri
2012-07-31 7:10 ` Marc Kleine-Budde
2012-07-31 11:57 ` Fabio Baltieri
2012-07-31 12:00 ` Marc Kleine-Budde
2012-07-31 22:05 ` [PATCH can-next v4] " Fabio Baltieri
2012-08-01 9:36 ` Marc Kleine-Budde
2012-08-01 10:07 ` Marc Kleine-Budde
2012-08-01 10:30 ` Fabio Baltieri
2012-08-01 11:37 ` Marc Kleine-Budde
2012-08-01 11:49 ` [PATCH can-next v5 1/2] " Fabio Baltieri
2012-08-01 11:49 ` [PATCH can-next v5 2/2] can: flexcan: add " Fabio Baltieri
2012-08-01 11:53 ` Marc Kleine-Budde
2012-08-01 12:24 ` Fabio Baltieri
2012-08-01 12:30 ` Marc Kleine-Budde
2012-08-01 21:02 ` Marc Kleine-Budde
2012-08-01 11:59 ` [PATCH can-next v5 1/2] can: add tx/rx " Marc Kleine-Budde
2012-08-01 12:06 ` Oliver Hartkopp
2012-08-01 12:18 ` Marc Kleine-Budde
2012-08-01 18:21 ` [PATCH can-next v6] " Fabio Baltieri
2012-08-01 21:00 ` Marc Kleine-Budde
2012-08-01 22:38 ` Fabio Baltieri
2012-08-01 21:05 ` Oliver Hartkopp
2012-08-24 5:10 ` Kurt Van Dijck
2012-08-24 11:28 ` Marc Kleine-Budde
2012-08-24 12:42 ` Kurt Van Dijck
2012-08-24 22:01 ` Fabio Baltieri
2012-08-25 20:25 ` Kurt Van Dijck
2012-09-03 12:40 ` Marc Kleine-Budde
2012-09-03 18:13 ` Kurt Van Dijck
2012-09-03 18:29 ` Fabio Baltieri
2012-09-03 20:54 ` Oliver Hartkopp
2012-09-04 7:11 ` Kurt Van Dijck
2012-09-04 9:29 ` [PATCH] can: rename LED trigger name on netdev renames Kurt Van Dijck
2012-09-06 18:59 ` Fabio Baltieri
2012-09-06 19:31 ` Oliver Hartkopp
2012-09-06 20:46 ` Fabio Baltieri
2012-09-07 7:19 ` Kurt Van Dijck
2012-09-09 16:17 ` [PATCH v2] " Fabio Baltieri
2012-09-10 14:25 ` [PATCH] can: export a safe netdev_priv wrapper for candev Kurt Van Dijck
2012-09-10 18:22 ` Oliver Hartkopp
2012-09-10 18:29 ` Fabio Baltieri
2012-09-10 19:55 ` [PATCH v2] " Kurt Van Dijck
2012-09-10 14:28 ` [PATCH v3] can: rename LED trigger name on netdev renames Kurt Van Dijck
2012-09-10 18:25 ` Oliver Hartkopp
2012-09-10 18:40 ` Fabio Baltieri
2012-09-10 19:01 ` Oliver Hartkopp
2012-09-10 20:08 ` Kurt Van Dijck
2012-09-11 5:42 ` Oliver Hartkopp
2012-09-11 7:13 ` Fabio Baltieri
2012-09-12 7:22 ` Kurt Van Dijck
2012-09-11 8:05 ` Kurt Van Dijck
2012-09-10 20:06 ` [PATCH v4] " Kurt Van Dijck
2012-09-11 21:04 ` Fabio Baltieri
2012-09-04 20:15 ` Fabio Baltieri [this message]
2012-09-06 10:33 ` [PATCH can-next v6] can: add tx/rx LED trigger support Kurt Van Dijck
2012-09-06 11:17 ` Fabio Baltieri
2012-09-06 15:11 ` Kurt Van Dijck
2012-09-06 20:57 ` Fabio Baltieri
2012-09-07 7:04 ` Kurt Van Dijck
2012-09-07 18:59 ` Fabio Baltieri
2012-07-31 8:46 ` [PATCH can-next v3 1/2] " Wolfgang Grandegger
2012-07-31 10:12 ` Marc Kleine-Budde
2012-07-31 11:55 ` Fabio Baltieri
2012-07-31 12:14 ` Fabio Baltieri
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