Subject: Re: [PATCH net-next] net: dsa: qca8k: Initialize the switch with correct number of ports

From: Andrew Lunn <[email-masked]>
Date: Thu, 24 Oct 2019 16:12:11 +0200

On Thu, Oct 24, 2019 at 03:46:58PM +0200, Michal Vokáč wrote:
> Since commit 0394a63acfe2 ("net: dsa: enable and disable all ports")
> the dsa core disables all unused ports of a switch. In this case
> disabling ports with numbers higher than QCA8K_NUM_PORTS causes that
> some switch registers are overwritten with incorrect content.

Humm.

The same problem might exist in other drivers:

linux/drivers/net/dsa$ grep -r "ds->num_ports = DSA_MAX_PORTS"
qca8k.c:	priv->ds->num_ports = DSA_MAX_PORTS;
b53/b53_common.c:	ds->num_ports = DSA_MAX_PORTS;
mt7530.c:	priv->ds->num_ports = DSA_MAX_PORTS;
microchip/ksz_common.c:	ds->num_ports = DSA_MAX_PORTS;
dsa_loop.c:	ds->num_ports = DSA_MAX_PORTS;

dsa_loop.c looks O.K, it does support DSA_MAX_PORTS ports.

But the others?

    Andrew