# Re: \[PATCH 2/2\] powerpc/85xx: add Fman MDIO muxing support to the P4080DS

- From: Timur Tabi \<hidden\>
- Date: 2012-08-14 21:58:40 
- List: linuxppc-dev
- Page: https://ratatoskr.run/linuxppc-dev/2012/08/9470809
- Thread: https://ratatoskr.run/netdev/2012/08/9470781/t.md

```text
Scott Wood wrote:

> I think that was internally, and not on this specific comment wording.
> I don't think that code comment adequately explains things.

I don't really have any more insight to add.

>> otherwise, the mdio-mux code would not prepare the mdio mus in time, and
>> there would be initialization failures.  Now maybe this goes away with
>> -EPROBE_DEFER, or maybe it doesn't.  But until we push the DPAA drivers
>> upstream, we won't know.
> 
> Do you know if it's theoretically supposed to be fixed and just can't
> test it, or are you unsure of whether it's even supposed to work?

I'm not sure of anything.  For one thing, we don't implement EPROBE_DEFER
in the DPAA drivers, so we'd probably have to fix that before anything.
And then, I'm just guessing that's the solution.

> I don't think we should be relying on the order of this list to
> determine probe order.  For one thing, it won't work if the drivers
> register after you create the platform devices (e.g. they're modules).

I agree we should not be relying on the order, but I don't know what to
do.  EPROBE_DEFER was designed to handle this situation, so my
recommendation is to worry about it later.  I can beef up the comment to
talk about that, if you want.

-- 
Timur Tabi
Linux kernel developer at Freescale
```