net: phy: micrel: disable NAND-tree for KSZ8051
NAND-tree is used to check wiring between MAC and PHY using NAND gates
on the PHY side, hence the name.
NAND-tree initial status is latched at reset by probing the IRQ pin.
However some devices are sharing the PHY IRQ pin with other peripherals
such as Atmel SAMA5D[34]x-EK boards when using the optional TM7000
display module, therefore they are switching the PHY in NAND-tree test
mode depending on the current IRQ line status at reset.
This patch ensure PHY is not in NAND-tree test mode only for the Micrel
KSZ8051 PHY used by Atmel. There are other Micrel PHY affected but I
doubt they are used on such weird hardware design.
Signed-off-by: Sylvain Rochet <sylvain.rochet@finsecur.com>
Acked-by: Joe Hershberger <joe.hershberger@ni.com>
diff --git a/drivers/net/phy/micrel.c b/drivers/net/phy/micrel.c
index cbec928..5e49666 100644
--- a/drivers/net/phy/micrel.c
+++ b/drivers/net/phy/micrel.c
@@ -32,6 +32,34 @@
.shutdown = &genphy_shutdown,
};
+/**
+ * KSZ8051
+ */
+#define MII_KSZ8051_PHY_OMSO 0x16
+#define MII_KSZ8051_PHY_OMSO_NAND_TREE_ON (1 << 5)
+
+static int ksz8051_config(struct phy_device *phydev)
+{
+ unsigned val;
+
+ /* Disable NAND-tree */
+ val = phy_read(phydev, MDIO_DEVAD_NONE, MII_KSZ8051_PHY_OMSO);
+ val &= ~MII_KSZ8051_PHY_OMSO_NAND_TREE_ON;
+ phy_write(phydev, MDIO_DEVAD_NONE, MII_KSZ8051_PHY_OMSO, val);
+
+ return genphy_config(phydev);
+}
+
+static struct phy_driver KSZ8051_driver = {
+ .name = "Micrel KSZ8051",
+ .uid = 0x221550,
+ .mask = 0xfffff0,
+ .features = PHY_BASIC_FEATURES,
+ .config = &ksz8051_config,
+ .startup = &genphy_startup,
+ .shutdown = &genphy_shutdown,
+};
+
static struct phy_driver KSZ8081_driver = {
.name = "Micrel KSZ8081",
.uid = 0x221560,
@@ -293,6 +321,7 @@
{
phy_register(&KSZ804_driver);
phy_register(&KSZ8031_driver);
+ phy_register(&KSZ8051_driver);
phy_register(&KSZ8081_driver);
#ifdef CONFIG_PHY_MICREL_KSZ9021
phy_register(&ksz9021_driver);