Re: [PATCH net-next] net: dsa: microchip: split adjust_link() in phylink_mac_link_{up|down}()

From: Russell King - ARM Linux admin
Date: Thu Jul 02 2020 - 06:21:21 EST


On Thu, Jul 02, 2020 at 12:54:39PM +0300, Codrin Ciubotariu wrote:
> The DSA subsystem moved to phylink and adjust_link() became deprecated in
> the process. This patch removes adjust_link from the KSZ DSA switches and
> adds phylink_mac_link_up() and phylink_mac_link_down().
>
> Signed-off-by: Codrin Ciubotariu <codrin.ciubotariu@xxxxxxxxxxxxx>

For the code _transformation_ that the patch does:

Reviewed-by: Russell King <rmk+kernel@xxxxxxxxxxxxxxx>

as it is equivalent. However, for a deeper review of what is going
on here, I've a question:

$ grep live_ports *
ksz8795.c: dev->live_ports = dev->host_mask;
ksz8795.c: dev->live_ports |= BIT(port);
ksz_common.h: u16 live_ports;
ksz_common.c: dev->live_ports &= ~(1 << port);
ksz_common.c: dev->live_ports |= (1 << port) & dev->on_ports;
ksz_common.c: dev->live_ports &= ~(1 << port);
ksz9477.c: dev->live_ports = dev->host_mask;
ksz9477.c: dev->live_ports |= (1 << port);

These are the only references to dev->live_ports, so the purpose of
dev->live_ports seems unclear; it seems it is only updated but never
read. Can it be removed, along with the locking in your new functions?

Thanks.

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