net: phy: dp83867: Add support for MAC impedance configuration

Add support for programmable MAC impedance configuration and
fix typo in DT impedance parameters names.

Signed-off-by: Mugunthan V N <mugunthanvnm@ti.com>
Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Tested-by: Lokesh Vutla <lokeshvutla@ti.com>
Acked-by: Joe Hershberger <joe.hershberger@ni.com>

arch/arm/dts/dra72-evm-revc.dts

@@ -67,7 +67,7 @@
 		ti,rx-internal-delay = <DP83867_RGMIIDCTL_2_25_NS>;
 		ti,tx-internal-delay = <DP83867_RGMIIDCTL_250_PS>;
 		ti,fifo-depth = <DP83867_PHYCR_FIFO_DEPTH_8_B_NIB>;
-		ti,min-output-imepdance;
+		ti,min-output-impedance;
 	};
 
 	dp83867_1: ethernet-phy@3 {
@@ -75,6 +75,6 @@
 		ti,rx-internal-delay = <DP83867_RGMIIDCTL_2_25_NS>;
 		ti,tx-internal-delay = <DP83867_RGMIIDCTL_250_PS>;
 		ti,fifo-depth = <DP83867_PHYCR_FIFO_DEPTH_8_B_NIB>;
-		ti,min-output-imepdance;
+		ti,min-output-impedance;
 	};
 };

drivers/net/phy/ti.c

@@ -27,6 +27,7 @@ DECLARE_GLOBAL_DATA_PTR;
 /* Extended Registers */
 #define DP83867_RGMIICTL	0x0032
 #define DP83867_RGMIIDCTL	0x0086
+#define DP83867_IO_MUX_CFG	0x0170
 
 #define DP83867_SW_RESET	BIT(15)
 #define DP83867_SW_RESTART	BIT(14)
@@ -84,10 +85,17 @@ DECLARE_GLOBAL_DATA_PTR;
 #define DEFAULT_TX_ID_DELAY	DP83867_RGMIIDCTL_2_75_NS
 #define DEFAULT_FIFO_DEPTH	DP83867_PHYCR_FIFO_DEPTH_4_B_NIB
 
+/* IO_MUX_CFG bits */
+#define DP83867_IO_MUX_CFG_IO_IMPEDANCE_CTRL	0x1f
+
+#define DP83867_IO_MUX_CFG_IO_IMPEDANCE_MAX	0x0
+#define DP83867_IO_MUX_CFG_IO_IMPEDANCE_MIN	0x1f
+
 struct dp83867_private {
 	int rx_id_delay;
 	int tx_id_delay;
 	int fifo_depth;
+	int io_impedance;
 };
 
 /**
@@ -166,6 +174,15 @@ static int dp83867_of_init(struct phy_device *phydev)
 {
 	struct dp83867_private *dp83867 = phydev->priv;
 	struct udevice *dev = phydev->dev;
+	int node = dev->of_offset;
+	const void *fdt = gd->fdt_blob;
+
+	if (fdtdec_get_bool(fdt, node, "ti,max-output-impedance"))
+		dp83867->io_impedance = DP83867_IO_MUX_CFG_IO_IMPEDANCE_MAX;
+	else if (fdtdec_get_bool(fdt, node, "ti,min-output-impedance"))
+		dp83867->io_impedance = DP83867_IO_MUX_CFG_IO_IMPEDANCE_MIN;
+	else
+		dp83867->io_impedance = -EINVAL;
 
 	dp83867->rx_id_delay = fdtdec_get_uint(gd->fdt_blob, dev->of_offset,
 				 "ti,rx-internal-delay", -1);
@@ -186,6 +203,7 @@ static int dp83867_of_init(struct phy_device *phydev)
 	dp83867->rx_id_delay = DEFAULT_RX_ID_DELAY;
 	dp83867->tx_id_delay = DEFAULT_TX_ID_DELAY;
 	dp83867->fifo_depth = DEFAULT_FIFO_DEPTH;
+	dp83867->io_impedance = -EINVAL;
 
 	return 0;
 }
@@ -268,6 +286,19 @@ static int dp83867_config(struct phy_device *phydev)
 
 		phy_write_mmd_indirect(phydev, DP83867_RGMIIDCTL,
 				       DP83867_DEVADDR, phydev->addr, delay);
+
+		if (dp83867->io_impedance >= 0) {
+			val = phy_read_mmd_indirect(phydev,
+						    DP83867_IO_MUX_CFG,
+						    DP83867_DEVADDR,
+						    phydev->addr);
+			val &= ~DP83867_IO_MUX_CFG_IO_IMPEDANCE_CTRL;
+			val |= dp83867->io_impedance &
+			       DP83867_IO_MUX_CFG_IO_IMPEDANCE_CTRL;
+			phy_write_mmd_indirect(phydev, DP83867_IO_MUX_CFG,
+					       DP83867_DEVADDR, phydev->addr,
+					       val);
+		}
 	}
 
 	genphy_config_aneg(phydev);