Subject: Re: [net-next RFC PATCH 1/6] net: phy: add support for defining multiple PHY IDs in PHY driver

From: Christian Marangi <[email-masked]>
Date: Sun, 18 Feb 2024 21:27:22 +0100

On Sun, Feb 18, 2024 at 09:10:30PM +0100, Andrew Lunn wrote:
> > > > +	phy_dev_id = (struct mdio_device_id *)&phydev->dev_id;
> > > 
> > > Why this cast? Try to write code that doesn't need casts.
> > > 
> > 
> > This cast is needed to keep the dev_id const in the phy_device struct so
> > that other are warned to not modify it and should only be handled by
> > phy_probe since it's the one that fills it.
> > 
> > Alternative is to drop const and drop the warning.
> 
> Can you propagate the const. Make phy_dev_id point to a const?
>

Mhh not following, I tried changing to const struct mdio_device_id *phy_dev_id
but that results in memcpy complain (dest is void * not const) and
writing in read-only for the single PHY part (the else part)

An alternative might be to make dev_id a pointer in struct phy_device
and dynamically allocate a mdio_device_id for the case of single PHY
(else case). That effectively remove the need of this cast but I would
love to skip checking for -ENOMEM (this is why i made that local)

If it's OK to dynamically allocate for the else case then I will make
this change. I just tested this implementation and works correctly with
not warning.

-- 
	Ansuel