net: micrel: Fix PTP frame parsing for lan8814

The HW has the capability to check each frame if it is a PTP frame,
which domain it is, which ptp frame type it is, different ip address in
the frame. And if one of these checks fail then the frame is not
timestamp. Most of these checks were disabled except checking the field
minorVersionPTP inside the PTP header. Meaning that once a partner sends
a frame compliant to 8021AS which has minorVersionPTP set to 1, then the
frame was not timestamp because the HW expected by default a value of 0
in minorVersionPTP. This is exactly the same issue as on lan8841.
Fix this issue by removing this check so the userspace can decide on this.

Fixes: ece1950 ("net: phy: micrel: 1588 support for LAN8814 phy")
Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Reviewed-by: Divya Koppera <divya.koppera@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Author: HoratiuVultur

drivers/net/phy/micrel.c

@@ -120,6 +120,11 @@
  */
 #define LAN8814_1PPM_FORMAT			17179
 
+#define PTP_RX_VERSION				0x0248
+#define PTP_TX_VERSION				0x0288
+#define PTP_MAX_VERSION(x)			(((x) & GENMASK(7, 0)) << 8)
+#define PTP_MIN_VERSION(x)			((x) & GENMASK(7, 0))
+
 #define PTP_RX_MOD				0x024F
 #define PTP_RX_MOD_BAD_UDPV4_CHKSUM_FORCE_FCS_DIS_ BIT(3)
 #define PTP_RX_TIMESTAMP_EN			0x024D
@@ -3150,6 +3155,12 @@ static void lan8814_ptp_init(struct phy_device *phydev)
 	lanphy_write_page_reg(phydev, 5, PTP_TX_PARSE_IP_ADDR_EN, 0);
 	lanphy_write_page_reg(phydev, 5, PTP_RX_PARSE_IP_ADDR_EN, 0);
 
+	/* Disable checking for minorVersionPTP field */
+	lanphy_write_page_reg(phydev, 5, PTP_RX_VERSION,
+			      PTP_MAX_VERSION(0xff) | PTP_MIN_VERSION(0x0));
+	lanphy_write_page_reg(phydev, 5, PTP_TX_VERSION,
+			      PTP_MAX_VERSION(0xff) | PTP_MIN_VERSION(0x0));
+
 	skb_queue_head_init(&ptp_priv->tx_queue);
 	skb_queue_head_init(&ptp_priv->rx_queue);
 	INIT_LIST_HEAD(&ptp_priv->rx_ts_list);