[PATCH net-next v2 4/6] net: phy: microchip_t1s: fix reset complete status handling

[Parthiban Veerasooran]

As per the datasheet DS-LAN8670-1-2-60001573C.pdf, the Reset Complete
status bit in the STS2 register to be checked before proceeding for the
initial configuration.

Signed-off-by: Parthiban Veerasooran <Parthiban.Veerasooran@xxxxxxxxxxxxx>
---
 drivers/net/phy/microchip_t1s.c | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/drivers/net/phy/microchip_t1s.c b/drivers/net/phy/microchip_t1s.c
index 869c7f403ea1..2f22a1954c09 100644
--- a/drivers/net/phy/microchip_t1s.c
+++ b/drivers/net/phy/microchip_t1s.c
@@ -14,6 +14,9 @@
 
 #define LAN867X_REG_IRQ_1_CTL 0x001C
 #define LAN867X_REG_IRQ_2_CTL 0x001D
+#define LAN867X_REG_STS2 0x0019
+
+#define LAN867x_RESET_COMPLETE_STS BIT(11)
 
 /* The arrays below are pulled from the following table from AN1699
  * Access MMD Address Value Mask
@@ -65,6 +68,27 @@ static int lan867x_revb1_config_init(struct phy_device *phydev)
 
 	int err;
 
+	/* Read STS2 register and check for the Reset Complete status to do the
+	 * init configuration. If the Reset Complete is not set, wait for 5us
+	 * and then read STS2 register again and check for Reset Complete status.
+	 * Still if it is failed then declare PHY reset error or else proceed
+	 * for the PHY initial register configuration.
+	 */
+	err = phy_read_mmd(phydev, MDIO_MMD_VEND2, LAN867X_REG_STS2);
+	if (err < 0)
+		return err;
+
+	if (!(err & LAN867x_RESET_COMPLETE_STS)) {
+		udelay(5);
+		err = phy_read_mmd(phydev, MDIO_MMD_VEND2, LAN867X_REG_STS2);
+		if (err < 0)
+			return err;
+		if (!(err & LAN867x_RESET_COMPLETE_STS)) {
+			phydev_err(phydev, "PHY reset failed\n");
+			return -ENODEV;
+		}
+	}
+
 	/* Read-Modified Write Pseudocode (from AN1699)
 	 * current_val = read_register(mmd, addr) // Read current register value
 	 * new_val = current_val AND (NOT mask) // Clear bit fields to be written
-- 
2.34.1