[PATCH] net: phy: micrel: workaround to NAND_Tree# incorrectly strapp-in during the reset period.

From: Wenyou Yang
Date: Sun Dec 07 2014 - 22:42:41 EST


Appearance: On some boards, after power up, the Ethernet doesn't work.

Reason: On the SAMA5D4EK, the PIOE2 pin is connected to the NAND_Tree# of KSZ8081,
But it outputs LOW during the reset period, which cause the NAND_Tree# enabled.

Workaround: In the .config_init(), add code to disable NAND_Tree#
by operating Operation Mode Strap Override(i.e. Register 16h).

Signed-off-by: Wenyou Yang <wenyou.yang@xxxxxxxxx>
---
drivers/net/phy/micrel.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/drivers/net/phy/micrel.c b/drivers/net/phy/micrel.c
index 8c2a29a..11d72cb 100644
--- a/drivers/net/phy/micrel.c
+++ b/drivers/net/phy/micrel.c
@@ -31,6 +31,7 @@
/* Operation Mode Strap Override */
#define MII_KSZPHY_OMSO 0x16
#define KSZPHY_OMSO_B_CAST_OFF (1 << 9)
+#define KSZPHY_OMSO_NAND_TREE_OVERRIDE (1 << 5)
#define KSZPHY_OMSO_RMII_OVERRIDE (1 << 1)
#define KSZPHY_OMSO_MII_OVERRIDE (1 << 0)

@@ -180,7 +181,12 @@ static int kszphy_setup_led(struct phy_device *phydev,

static int kszphy_config_init(struct phy_device *phydev)
{
- return 0;
+ int rc;
+
+ phy_write(phydev, MII_KSZPHY_OMSO, phy_read(phydev, MII_KSZPHY_OMSO)
+ & (~KSZPHY_OMSO_NAND_TREE_OVERRIDE));
+ rc = ksz_config_flags(phydev);
+ return rc < 0 ? rc : 0;
}

static int kszphy_config_init_led8041(struct phy_device *phydev)
--
1.7.9.5

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