Re: drivers/net/phy/phy.c issue

2012/2/8 Guenter Roeck [off-list ref]:

Copying netdev.

On Wed, 2012-02-08 at 09:31 -0500, Frans Meulenbroeks wrote:

quoted

Hi

I found an issue with drivers/net/phy/phy.c
As I could not identify a maintainer for this file I decided to mail
it to the above addressees.
Apologies upfront if it is inappropriate.

The issue:

My network interface was configured as 10Mbit, full duplex, autonegotiate off.
If the cable is unplugged after 10 seconds or so the interface drops
to half duplex and the message:
Trying 10/HALF
is printed. This message comes (if I am correct from the function
phy_force_reduction in drivers/net/phy/phy.c

Maybe this is still ok, however if I reconnect my network cable the
interface remains configured as 10 Mbit, half duplex.
I had expected/assumed that it would go back to 10 Mbit, full duplex.

If I try the same with a 1Gbit full duplex link with autonegotiate on,
the link also drops to half duplex whenever the cable is
disconnected. However reconnecting the cable then brings the interface
back to full duplex again.

Not sure what is wrong (if the interface should not be dropped to half
or get back to full) and even less an idea how to fix it,
but wanted to report it anyway, in the hope someone can shed a light
on this and/or fix it.

What is your kernel version ? No idea if it makes a difference, but I
strongly suspect people will need to know.

Oops, sorry for the incomplete info.
This was detected in 2.6.38, but the current git head of phy.c differs
only on a few places that (at least according to my judgement) are not
related.
Apologies, but I cannot test on a git head kernel.

And wrt the question of Andy in the subsequent reply.

Hw is a Freescale MPC8313. This is a Gianfar. Is that the info you wanted?

BTW what is the desired behaviour? Should I drop to half duplex? Or
should I get back to full if I reconnect.

Best regards, Frans