Re: [PATCH v1 1/2] driver core: fw_devlink: Add support for FWNODE_FLAG_BROKEN_PARENT

Saravana Kannan
2021-09-30T19:49:24Z

On Thu, Sep 30, 2021 at 12:38 PM Andrew Lunn <andrew@lunn.ch> wrote:
>
> > Btw, do we have non-DSA networking devices where fw_devlink=on
> > delaying PHY probes is causing an issue?
>
> I don't know if issues have been reported, but the realtek driver has
> had problems in the past when the generic driver is used. Take a look
> at r8169_mdio_register(), it does something similar to DSA.

Does it have the issue of having the PHY as its child too and then
depending on it to bind to a driver? I can't tell because I didn't
know how to find that info for a PCI device.

>
> What is going to make things interesting is that phy_attach_direct()
> is called in two different contexts. During the MAC drivers probe, it
> is O.K. to return EPROBE_DEFER, and let the MAC driver try again
> later, if we know there is a specific PHY driver for it. But when
> called during the MAC drivers open() op, -EPROBE_DEFER is not
> allowed. What to do then is an interesting question.

Yeah, basically before doing an open() it'll have to call an API to
say "just bind with whatever you got". Or something along those lines.
I already know how to get that to work. I'll send some RFC soonish (I
hope).

-Saravana