Subject: Re: [RFC PATCH 5/6] ethernet: dfl-eth-group: add DFL eth group private feature driver

From: Andrew Lunn <[email-masked]>
Date: Sun, 25 Oct 2020 15:47:22 +0100

> > +u64 read_mac_stats(struct eth_com *ecom, unsigned int addr)
> > +{
> > +	u32 data_l, data_h;
> > +
> > +	if (eth_com_read_reg(ecom, addr, &data_l) ||
> > +	    eth_com_read_reg(ecom, addr + 1, &data_h))
> > +		return 0xffffffffffffffffULL;

> return -1; ?

Since this is a u64 function, i expect you get a compiler
warning. Maybe only with W=1. It is better to use U64_MAX.

	 Andrew