[PATCH net-next v8 02/15] phylib: Add support for PHYs with broken forced mode

[Birger Koblitz <mail@birger-koblitz.de>]

Add support for PHYs which only supported auto-negotiated
speed modes. This prevents a kernel warning and stack-trace within the
phy_state_machine when PHYs return -EOPNOTSUPP from config_aneg()
because they do not support forced modes.

Signed-off-by: Birger Koblitz <mail@birger-koblitz.de>
---
 drivers/net/phy/phy.c | 4 ++++
 include/linux/phy.h   | 1 +
 2 files changed, 5 insertions(+)

diff --git a/drivers/net/phy/phy.c b/drivers/net/phy/phy.c
index fce9bc7be3304b408c9f3ec9b5b95c76d3680a88..b83f938fe7c3bd619ae453434fd9582c0a055a57 100644
--- a/drivers/net/phy/phy.c
+++ b/drivers/net/phy/phy.c
@@ -1190,6 +1190,10 @@ int phy_ethtool_ksettings_set(struct phy_device *phydev,
 	      duplex != DUPLEX_FULL)))
 		return -EINVAL;
 
+	if (autoneg == AUTONEG_DISABLE &&
+	    (phydev->drv->flags & PHY_BROKEN_FORCED))
+		return -EOPNOTSUPP;
+
 	mutex_lock(&phydev->lock);
 	phydev->autoneg = autoneg;
 
diff --git a/include/linux/phy.h b/include/linux/phy.h
index 199a7aaa341bfd9b13731e996a8de7e1aea586ff..8169c0b0fd28f3a52d2905611820ec8954383587 100644
--- a/include/linux/phy.h
+++ b/include/linux/phy.h
@@ -64,6 +64,7 @@ extern const int phy_basic_ports_array[3];
 #define PHY_RST_AFTER_CLK_EN	0x00000002
 #define PHY_POLL_CABLE_TEST	0x00000004
 #define PHY_ALWAYS_CALL_SUSPEND	0x00000008
+#define PHY_BROKEN_FORCED	0x00000010
 #define MDIO_DEVICE_IS_PHY	0x80000000
 
 /**

-- 
2.47.3