Commit 4a3e0aed authored Oct 11, 2021 by Maarten Zanders Committed by David S. Miller Oct 12, 2021

net: dsa: mv88e6xxx: don't use PHY_DETECT on internal PHY's



mv88e6xxx_port_ppu_updates() interpretes data in the PORT_STS
register incorrectly for internal ports (ie no PPU). In these
cases, the PHY_DETECT bit indicates link status. This results
in forcing the MAC state whenever the PHY link goes down which
is not intended. As a side effect, LED's configured to show
link status stay lit even though the physical link is down.

Add a check in mac_link_down and mac_link_up to see if it
concerns an external port and only then, look at PPU status.

Fixes: 5d5b231d (net: dsa: mv88e6xxx: use PHY_DETECT in mac_link_up/mac_link_down)
Reported-by: Maarten Zanders <m.zanders@televic.com>
Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: Maarten Zanders <maarten.zanders@mind.be>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent 74a3bc42

drivers/net/dsa/mv88e6xxx/chip.c

+11 −2

Original line number	Diff line number	Diff line
		@@ -750,7 +750,11 @@ static void mv88e6xxx_mac_link_down(struct dsa_switch *ds, int port,
		ops = chip->info->ops;

		mv88e6xxx_reg_lock(chip);
		if ((!mv88e6xxx_port_ppu_updates(chip, port) \|\|
		/* Internal PHYs propagate their configuration directly to the MAC.
		* External PHYs depend on whether the PPU is enabled for this port.
		*/
		if (((!mv88e6xxx_phy_is_internal(ds, port) &&
		!mv88e6xxx_port_ppu_updates(chip, port)) \|\|
		mode == MLO_AN_FIXED) && ops->port_sync_link)
		err = ops->port_sync_link(chip, port, mode, false);
		mv88e6xxx_reg_unlock(chip);
		@@ -773,7 +777,12 @@ static void mv88e6xxx_mac_link_up(struct dsa_switch *ds, int port,
		ops = chip->info->ops;

		mv88e6xxx_reg_lock(chip);
		if (!mv88e6xxx_port_ppu_updates(chip, port) \|\| mode == MLO_AN_FIXED) {
		/* Internal PHYs propagate their configuration directly to the MAC.
		* External PHYs depend on whether the PPU is enabled for this port.
		*/
		if ((!mv88e6xxx_phy_is_internal(ds, port) &&
		!mv88e6xxx_port_ppu_updates(chip, port)) \|\|
		mode == MLO_AN_FIXED) {
		/* FIXME: for an automedia port, should we force the link
		* down here - what if the link comes up due to "other" media
		* while we're bringing the port up, how is the exclusivity