4.8-stable review patch. If anyone has any objections, please let me know.
------------------
From: Florian Fainelli <f.faine...@gmail.com>
[ Upstream commit c51e424dc79e1428afc4d697cdb6a07f7af70cbf ]
Commit 52f95bbfcf72 ("stmmac: fix adjust link call in case of a switch
is attached") added some logic to avoid polling the fixed PHY and
therefore invoking the adjust_link callback more than once, since this
is a fixed PHY and link events won't be generated.
This works fine the first time, because we start with phydev->irq =
PHY_POLL, so we call adjust_link, then we set phydev->irq =
PHY_IGNORE_INTERRUPT and we stop polling the PHY.
Now, if we called ndo_close(), which calls both phy_stop() and does an
explicit netif_carrier_off(), we end up with a link down. Upon calling
ndo_open() again, despite starting the PHY state machine, we have
PHY_IGNORE_INTERRUPT set, and we generate no link event at all, so the
link is permanently down.
Fixes: 52f95bbfcf72 ("stmmac: fix adjust link call in case of a switch is
attached")
Signed-off-by: Florian Fainelli <f.faine...@gmail.com>
Acked-by: Giuseppe Cavallaro <peppe.cavall...@st.com>
Signed-off-by: David S. Miller <da...@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
---
drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 7 +++++++
1 file changed, 7 insertions(+)
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -871,6 +871,13 @@ static int stmmac_init_phy(struct net_de
return -ENODEV;
}
+ /* stmmac_adjust_link will change this to PHY_IGNORE_INTERRUPT to avoid
+ * subsequent PHY polling, make sure we force a link transition if
+ * we have a UP/DOWN/UP transition
+ */
+ if (phydev->is_pseudo_fixed_link)
+ phydev->irq = PHY_POLL;
+
pr_debug("stmmac_init_phy: %s: attached to PHY (UID 0x%x)"
" Link = %d\n", dev->name, phydev->phy_id, phydev->link);
