When initializing the PHY control register, the FIFO depth bits are
written without reading the previous register value, i.e. all other
bits are overwritten with zero. This disables automatic MDI-X
configuration, which is enabled by default. Fix initialization by doing
a read/modify/write operation.
Signed-off-by: Stefan Hauser <redacted>
---
drivers/net/phy/dp83867.c | 13 +++++++++----
1 file changed, 9 insertions(+), 4 deletions(-)
diff --git a/drivers/net/phy/dp83867.c b/drivers/net/phy/dp83867.c
index 2afa61b..91177a4 100644
--- a/drivers/net/phy/dp83867.c
+++ b/drivers/net/phy/dp83867.c
@@ -57,6 +57,7 @@
/* PHY CTRL bits */
#define DP83867_PHYCR_FIFO_DEPTH_SHIFT 14
+#define DP83867_PHYCR_FIFO_DEPTH_MASK (3 << 14)
/* RGMIIDCTL bits */
#define DP83867_RGMII_TX_CLK_DELAY_SHIFT 4
@@ -133,8 +134,8 @@ static int dp83867_of_init(struct phy_device *phydev)
static int dp83867_config_init(struct phy_device *phydev)
{
struct dp83867_private *dp83867;
- int ret;
- u16 val, delay;
+ int ret, val;
+ u16 delay;
if (!phydev->priv) {
dp83867 = devm_kzalloc(&phydev->mdio.dev, sizeof(*dp83867),@@ -151,8 +152,12 @@ static int dp83867_config_init(struct phy_device *phydev)
}
if (phy_interface_is_rgmii(phydev)) {
- ret = phy_write(phydev, MII_DP83867_PHYCTRL,
- (dp83867->fifo_depth << DP83867_PHYCR_FIFO_DEPTH_SHIFT));
+ val = phy_read(phydev, MII_DP83867_PHYCTRL);
+ if (val < 0)
+ return val;
+ val &= ~DP83867_PHYCR_FIFO_DEPTH_MASK;
+ val |= (dp83867->fifo_depth << DP83867_PHYCR_FIFO_DEPTH_SHIFT);
+ ret = phy_write(phydev, MII_DP83867_PHYCTRL, val);
if (ret)
return ret;
}--
1.9.1