[U-Boot] [PATCH] net: phy: micrel: center FLP burst timing at 16ms

[Ash Charles]

Like [1], reset the FLP burst timing for the KSZ9031 to the 16ms
specified by the IEEE802.3 standard from the chip's default of 8ms.

For more details, see the "Auto-Negotiation Timing" section of the
KSZ9031RNX datasheet.

[1] https://patchwork.kernel.org/patch/6558371/

Change-Id: I122ee33300db3a617cc527070b4e97b88563d7a7
Signed-off-by: Ash Charles <ash.charles at savoirfairelinux.com>
---
 drivers/net/phy/micrel.c | 23 +++++++++++++++++++++++
 include/micrel.h         |  3 +++
 2 files changed, 26 insertions(+)

diff --git a/drivers/net/phy/micrel.c b/drivers/net/phy/micrel.c
index 6b313a9..28a1401 100644
--- a/drivers/net/phy/micrel.c
+++ b/drivers/net/phy/micrel.c
@@ -415,11 +415,31 @@ static int ksz9031_of_config(struct phy_device *phydev)
 
 	return 0;
 }
+
+static int ksz9031_center_flp_timing(struct phy_device *phydev)
+{
+	struct phy_driver *drv = phydev->drv;
+	int ret = 0;
+
+	if (!drv || !drv->writeext)
+		return -EOPNOTSUPP;
+
+	ret = drv->writeext(phydev, 0, 0, MII_KSZ9031_FLP_BURST_TX_LO, 0x1A80);
+	if (ret)
+		return ret;
+
+	ret = drv->writeext(phydev, 0, 0, MII_KSZ9031_FLP_BURST_TX_HI, 0x6);
+	return ret;
+}
 #else
 static int ksz9031_of_config(struct phy_device *phydev)
 {
 	return 0;
 }
+static int ksz9031_center_flp_timing(struct phy_device *phydev)
+{
+	return 0;
+}
 #endif
 
 /* Accessors to extended registers*/
@@ -472,6 +492,9 @@ static int ksz9031_config(struct phy_device *phydev)
 	ret = ksz9031_of_config(phydev);
 	if (ret)
 		return ret;
+	ret = ksz9031_center_flp_timing(phydev);
+	if (ret)
+		return ret;
 	return genphy_config(phydev);
 }
 
diff --git a/include/micrel.h b/include/micrel.h
index e6d145d..3e6b531 100644
--- a/include/micrel.h
+++ b/include/micrel.h
@@ -20,6 +20,9 @@
 #define MII_KSZ9031_EXT_RGMII_TX_DATA_SKEW	0x6
 #define MII_KSZ9031_EXT_RGMII_CLOCK_SKEW	0x8
 
+#define MII_KSZ9031_FLP_BURST_TX_LO		0x3
+#define MII_KSZ9031_FLP_BURST_TX_HI		0x4
+
 /* Registers */
 #define MMD_ACCESS_CONTROL	0xd
 #define MMD_ACCESS_REG_DATA	0xe
-- 
2.7.4