fwip(4) carrier detection

[Roy Marples-2]

Hi List

fwip(4) lacks carrier detection that most other drivers offer.
How hard would it be to add?

Or another solution for me would be to rely on SIOCGIFMEDIA working down the
interface is down. This seems to work for bge(4) - should this generally be
the case?

Thanks

Roy

[Quentin Garnier]

On Tue, Oct 13, 2009 at 09:19:00PM +0100, Roy Marples wrote:
> Hi List
>
> fwip(4) lacks carrier detection that most other drivers offer.
> How hard would it be to add?
>
> Or another solution for me would be to rely on SIOCGIFMEDIA working down the
> interface is down. This seems to work for bge(4) - should this generally be
> the case?

What does carrier detection mean in the context of fwip(4)?  What in
your opinion should happen for a host that has more than one firewire
port and only one controller?

You have to keep in mind fwip(4) is not Ethernet.

--
Quentin Garnier - cube@... - cube@...
"See the look on my face from staying too long in one place
[...] every time the morning breaks I know I'm closer to falling"
KT Tunstall, Saving My Face, Drastic Fantastic, 2007.

[Roy Marples-2]

Quentin Garnier wrote:

> On Tue, Oct 13, 2009 at 09:19:00PM +0100, Roy Marples wrote:
>> Hi List
>>
>> fwip(4) lacks carrier detection that most other drivers offer.
>> How hard would it be to add?
>>
>> Or another solution for me would be to rely on SIOCGIFMEDIA working down the
>> interface is down. This seems to work for bge(4) - should this generally be
>> the case?
>
> What does carrier detection mean in the context of fwip(4)?  What in
> your opinion should happen for a host that has more than one firewire
> port and only one controller?
>
> You have to keep in mind fwip(4) is not Ethernet.

Well, on my systems I have fwip0 reported as an interface.
It does not advertise carrier, so dhcpcd will automatically try and get
an IP address and fail. This normally isn't an issue, but I'm looking at
getting dhcpcd to background when after getting an IP or no interface
has a carrier. NetBSD is my only system where fwip0 is visible by
default, so I'd like to get something done, either in dhcpcd or in NetBSD.

Thanks

Roy

[David Young]

On Wed, Oct 14, 2009 at 07:57:33PM +0200, Quentin Garnier wrote:

> On Tue, Oct 13, 2009 at 09:19:00PM +0100, Roy Marples wrote:
> > Hi List
> >
> > fwip(4) lacks carrier detection that most other drivers offer.
> > How hard would it be to add?
> >
> > Or another solution for me would be to rely on SIOCGIFMEDIA working down the
> > interface is down. This seems to work for bge(4) - should this generally be
> > the case?
>
> What does carrier detection mean in the context of fwip(4)?  What in
> your opinion should happen for a host that has more than one firewire
> port and only one controller?
>
> You have to keep in mind fwip(4) is not Ethernet.

IIUC, ports belonging to the same controller form a "broadcast" network,
that is, devices on port A are addressable by devices on port B, and
vice versa, for any two ports A or B.  In other words, the FireWire
controller acts analogously to an ethernet hub/switch for its ports.
In that case, if there is no "live" device attached to any port, the
appropriate media status is 'no carrier'.  If there is a live device on
any single port, however, the media status should be 'active'.

I don't know if there is any way to detect the status of any single
port.  I *do* think that you can enumerate the nodes on the FireWire
bus.  If there is just one node, the local host, 'no carrier' seems
right, and if there are two or more nodes, then 'active'.

Dave

--
David Young             OJC Technologies
dyoung@...      Urbana, IL * [phone]

[is-14]

On Fri, Nov 06, 2009 at 03:55:26PM -0600, David Young wrote:

> I don't know if there is any way to detect the status of any single
> port.  I *do* think that you can enumerate the nodes on the FireWire
> bus.  If there is just one node, the local host, 'no carrier' seems
> right, and if there are two or more nodes, then 'active'.

This sounds good to me. Who'll implement?

        -is
--