Merge branch 'net-phy-realtek-pair-order-and-polarity'

Damien Dejean says:

====================
net: phy: realtek: pair order and polarity

The RTL8224 PHY gives the manufacturer some flexbility with the pair
order and polarity to ease the wiring on the PCB. Then the correct pair
order and pair polarity must be provided to the PHY to function
properly. This series adds the support to configure the pair order and
the pair polarity to the Realtek PHY driver.
====================

Link: https://patch.msgid.link/20260318215502.106528-1-dam.dejean@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

3 files changed, 111 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/net/ethernet-phy.yaml b/Documentation/devicetree/bindings/net/ethernet-phy.yaml
index 58634fee9fc4..21a1a63506f0 100644
--- a/Documentation/devicetree/bindings/net/ethernet-phy.yaml
+++ b/Documentation/devicetree/bindings/net/ethernet-phy.yaml
@@ -126,6 +126,20 @@ properties:
       e.g. wrong bootstrap configuration caused by issues in PCB
       layout design.
 
+  enet-phy-pair-order:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    enum: [0, 1]
+    description:
+      For normal (0) or reverse (1) order of the pairs (ABCD -> DCBA).
+
+  enet-phy-pair-polarity:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    maximum: 0xf
+    description:
+      A bitmap to describe pair polarity swap. Bit 0 to swap polarity of pair A,
+      bit 1 to swap polarity of pair B, bit 2 to swap polarity of pair C and bit
+      3 to swap polarity of pair D.
+
   eee-broken-100tx:
     $ref: /schemas/types.yaml#/definitions/flag
     description:
diff --git a/drivers/net/phy/realtek/Kconfig b/drivers/net/phy/realtek/Kconfig
index b05c2a1e9024..a741b34d193e 100644
--- a/drivers/net/phy/realtek/Kconfig
+++ b/drivers/net/phy/realtek/Kconfig
@@ -1,6 +1,7 @@
 # SPDX-License-Identifier: GPL-2.0-only
 config REALTEK_PHY
 	tristate "Realtek PHYs"
+	select PHY_PACKAGE
 	help
 	  Currently supports RTL821x/RTL822x and fast ethernet PHYs
 
diff --git a/drivers/net/phy/realtek/realtek_main.c b/drivers/net/phy/realtek/realtek_main.c
index 530b4e26d16e..023e47ad605b 100644
--- a/drivers/net/phy/realtek/realtek_main.c
+++ b/drivers/net/phy/realtek/realtek_main.c
@@ -171,6 +171,9 @@
 
 #define RTL8224_SRAM_RTCT_LEN(pair)		(0x8028 + (pair) * 4)
 
+#define RTL8224_VND1_MDI_PAIR_SWAP		0xa90
+#define RTL8224_VND1_MDI_POLARITY_SWAP		0xa94
+
 #define RTL8366RB_POWER_SAVE			0x15
 #define RTL8366RB_POWER_SAVE_ON			BIT(12)
 
@@ -1820,6 +1823,97 @@ static int rtl8224_cable_test_get_status(struct phy_device *phydev, bool *finish
 	return rtl8224_cable_test_report(phydev, finished);
 }
 
+static int rtl8224_package_modify_mmd(struct phy_device *phydev, int devad,
+				      u32 regnum, u16 mask, u16 set)
+{
+	int val, ret;
+
+	phy_lock_mdio_bus(phydev);
+
+	val = __phy_package_read_mmd(phydev, 0, devad, regnum);
+	if (val < 0) {
+		ret = val;
+		goto exit;
+	}
+
+	val &= ~mask;
+	val |= set;
+
+	ret = __phy_package_write_mmd(phydev, 0, devad, regnum, val);
+
+exit:
+	phy_unlock_mdio_bus(phydev);
+	return ret;
+}
+
+static int rtl8224_mdi_config_order(struct phy_device *phydev)
+{
+	struct device_node *np = phydev->mdio.dev.of_node;
+	u8 port_offset = phydev->mdio.addr & 3;
+	u32 order = 0;
+	int ret;
+
+	ret = of_property_read_u32(np, "enet-phy-pair-order", &order);
+
+	/* Do nothing in case the property is not present */
+	if (ret == -EINVAL || ret == -ENOSYS)
+		return 0;
+
+	if (ret)
+		return ret;
+
+	if (order & ~1)
+		return -EINVAL;
+
+	return rtl8224_package_modify_mmd(phydev, MDIO_MMD_VEND1,
+					  RTL8224_VND1_MDI_PAIR_SWAP,
+					  BIT(port_offset),
+					  order ? BIT(port_offset) : 0);
+}
+
+static int rtl8224_mdi_config_polarity(struct phy_device *phydev)
+{
+	struct device_node *np = phydev->mdio.dev.of_node;
+	u8 offset = (phydev->mdio.addr & 3) * 4;
+	u32 polarity = 0;
+	int ret;
+
+	ret = of_property_read_u32(np, "enet-phy-pair-polarity", &polarity);
+
+	/* Do nothing if the property is not present */
+	if (ret == -EINVAL || ret == -ENOSYS)
+		return 0;
+
+	if (ret)
+		return ret;
+
+	if (polarity & ~0xf)
+		return -EINVAL;
+
+	return rtl8224_package_modify_mmd(phydev, MDIO_MMD_VEND1,
+					  RTL8224_VND1_MDI_POLARITY_SWAP,
+					  0xf << offset,
+					  polarity << offset);
+}
+
+static int rtl8224_config_init(struct phy_device *phydev)
+{
+	int ret;
+
+	ret = rtl8224_mdi_config_order(phydev);
+	if (ret)
+		return ret;
+
+	return rtl8224_mdi_config_polarity(phydev);
+}
+
+static int rtl8224_probe(struct phy_device *phydev)
+{
+	/* Chip exposes 4 ports, join all of them in the same package */
+	return devm_phy_package_join(&phydev->mdio.dev, phydev,
+				     phydev->mdio.addr & ~3, 0);
+}
+
 static bool rtlgen_supports_2_5gbps(struct phy_device *phydev)
 {
 	int val;
@@ -2395,6 +2489,8 @@ static struct phy_driver realtek_drvs[] = {
 		PHY_ID_MATCH_EXACT(0x001ccad0),
 		.name		= "RTL8224 2.5Gbps PHY",
 		.flags		= PHY_POLL_CABLE_TEST,
+		.probe		= rtl8224_probe,
+		.config_init	= rtl8224_config_init,
 		.get_features	= rtl822x_c45_get_features,
 		.config_aneg	= rtl822x_c45_config_aneg,
 		.read_status	= rtl822x_c45_read_status,