net: phy: realtek: Add driver instances for rtl8221b via Clause 45

Collected from several commits in [PATCH net-next]
"Realtek RTL822x PHY rework to c45 and SerDes interface switching"

The instances are used by Clause 45 only accessible PHY's on several sfp
modules, which are using RollBall protocol.
Signed-off-by: Marek Behún <kabel@kernel.org>
[ Added matching functions to differentiate C45 instances ]
Signed-off-by: Eric Woudstra <ericwouds@gmail.com>
Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/phy/realtek.c

@@ -64,6 +64,13 @@
 #define RTL822X_VND1_SERDES_CTRL3_MODE_SGMII			0x02
 #define RTL822X_VND1_SERDES_CTRL3_MODE_2500BASEX		0x16
 
+/* RTL822X_VND2_XXXXX registers are only accessible when phydev->is_c45
+ * is set, they cannot be accessed by C45-over-C22.
+ */
+#define RTL822X_VND2_GBCR				0xa412
+
+#define RTL822X_VND2_GANLPAR				0xa414
+
 #define RTL8366RB_POWER_SAVE			0x15
 #define RTL8366RB_POWER_SAVE_ON			BIT(12)
 
@@ -74,6 +81,9 @@
 
 #define RTL_GENERIC_PHYID			0x001cc800
 #define RTL_8211FVD_PHYID			0x001cc878
+#define RTL_8221B_VB_CG				0x001cc849
+#define RTL_8221B_VN_CG				0x001cc84a
+#define RTL_8251B				0x001cc862
 
 MODULE_DESCRIPTION("Realtek PHY driver");
 MODULE_AUTHOR("Johnson Leung");
@@ -839,6 +849,67 @@ static int rtl822xb_read_status(struct phy_device *phydev)
 	return 0;
 }
 
+static int rtl822x_c45_config_aneg(struct phy_device *phydev)
+{
+	bool changed = false;
+	int ret, val;
+
+	if (phydev->autoneg == AUTONEG_DISABLE)
+		return genphy_c45_pma_setup_forced(phydev);
+
+	ret = genphy_c45_an_config_aneg(phydev);
+	if (ret < 0)
+		return ret;
+	if (ret > 0)
+		changed = true;
+
+	val = linkmode_adv_to_mii_ctrl1000_t(phydev->advertising);
+
+	/* Vendor register as C45 has no standardized support for 1000BaseT */
+	ret = phy_modify_mmd_changed(phydev, MDIO_MMD_VEND2, RTL822X_VND2_GBCR,
+				     ADVERTISE_1000FULL, val);
+	if (ret < 0)
+		return ret;
+	if (ret > 0)
+		changed = true;
+
+	return genphy_c45_check_and_restart_aneg(phydev, changed);
+}
+
+static int rtl822x_c45_read_status(struct phy_device *phydev)
+{
+	int ret, val;
+
+	ret = genphy_c45_read_status(phydev);
+	if (ret < 0)
+		return ret;
+
+	/* Vendor register as C45 has no standardized support for 1000BaseT */
+	if (phydev->autoneg == AUTONEG_ENABLE) {
+		val = phy_read_mmd(phydev, MDIO_MMD_VEND2,
+				   RTL822X_VND2_GANLPAR);
+		if (val < 0)
+			return val;
+
+		mii_stat1000_mod_linkmode_lpa_t(phydev->lp_advertising, val);
+	}
+
+	return 0;
+}
+
+static int rtl822xb_c45_read_status(struct phy_device *phydev)
+{
+	int ret;
+
+	ret = rtl822x_c45_read_status(phydev);
+	if (ret < 0)
+		return ret;
+
+	rtl822xb_update_interface(phydev);
+
+	return 0;
+}
+
 static bool rtlgen_supports_2_5gbps(struct phy_device *phydev)
 {
 	int val;
@@ -862,6 +933,35 @@ static int rtl8226_match_phy_device(struct phy_device *phydev)
 	       rtlgen_supports_2_5gbps(phydev);
 }
 
+static int rtlgen_is_c45_match(struct phy_device *phydev, unsigned int id,
+			       bool is_c45)
+{
+	if (phydev->is_c45)
+		return is_c45 && (id == phydev->c45_ids.device_ids[1]);
+	else
+		return !is_c45 && (id == phydev->phy_id);
+}
+
+static int rtl8221b_vb_cg_c22_match_phy_device(struct phy_device *phydev)
+{
+	return rtlgen_is_c45_match(phydev, RTL_8221B_VB_CG, false);
+}
+
+static int rtl8221b_vb_cg_c45_match_phy_device(struct phy_device *phydev)
+{
+	return rtlgen_is_c45_match(phydev, RTL_8221B_VB_CG, true);
+}
+
+static int rtl8221b_vn_cg_c22_match_phy_device(struct phy_device *phydev)
+{
+	return rtlgen_is_c45_match(phydev, RTL_8221B_VN_CG, false);
+}
+
+static int rtl8221b_vn_cg_c45_match_phy_device(struct phy_device *phydev)
+{
+	return rtlgen_is_c45_match(phydev, RTL_8221B_VN_CG, true);
+}
+
 static int rtlgen_resume(struct phy_device *phydev)
 {
 	int ret = genphy_resume(phydev);
@@ -872,6 +972,15 @@ static int rtlgen_resume(struct phy_device *phydev)
 	return ret;
 }
 
+static int rtlgen_c45_resume(struct phy_device *phydev)
+{
+	int ret = genphy_c45_pma_resume(phydev);
+
+	msleep(20);
+
+	return ret;
+}
+
 static int rtl9000a_config_init(struct phy_device *phydev)
 {
 	phydev->autoneg = AUTONEG_DISABLE;
@@ -1143,8 +1252,8 @@ static struct phy_driver realtek_drvs[] = {
 		.read_page      = rtl821x_read_page,
 		.write_page     = rtl821x_write_page,
 	}, {
-		PHY_ID_MATCH_EXACT(0x001cc849),
-		.name           = "RTL8221B-VB-CG 2.5Gbps PHY",
+		.match_phy_device = rtl8221b_vb_cg_c22_match_phy_device,
+		.name           = "RTL8221B-VB-CG 2.5Gbps PHY (C22)",
 		.get_features   = rtl822x_get_features,
 		.config_aneg    = rtl822x_config_aneg,
 		.config_init    = rtl822xb_config_init,
@@ -1155,8 +1264,17 @@ static struct phy_driver realtek_drvs[] = {
 		.read_page      = rtl821x_read_page,
 		.write_page     = rtl821x_write_page,
 	}, {
-		PHY_ID_MATCH_EXACT(0x001cc84a),
-		.name           = "RTL8221B-VM-CG 2.5Gbps PHY",
+		.match_phy_device = rtl8221b_vb_cg_c45_match_phy_device,
+		.name           = "RTL8221B-VB-CG 2.5Gbps PHY (C45)",
+		.config_init    = rtl822xb_config_init,
+		.get_rate_matching = rtl822xb_get_rate_matching,
+		.config_aneg    = rtl822x_c45_config_aneg,
+		.read_status    = rtl822xb_c45_read_status,
+		.suspend        = genphy_c45_pma_suspend,
+		.resume         = rtlgen_c45_resume,
+	}, {
+		.match_phy_device = rtl8221b_vn_cg_c22_match_phy_device,
+		.name           = "RTL8221B-VM-CG 2.5Gbps PHY (C22)",
 		.get_features   = rtl822x_get_features,
 		.config_aneg    = rtl822x_config_aneg,
 		.config_init    = rtl822xb_config_init,
@@ -1166,6 +1284,15 @@ static struct phy_driver realtek_drvs[] = {
 		.resume         = rtlgen_resume,
 		.read_page      = rtl821x_read_page,
 		.write_page     = rtl821x_write_page,
+	}, {
+		.match_phy_device = rtl8221b_vn_cg_c45_match_phy_device,
+		.name           = "RTL8221B-VN-CG 2.5Gbps PHY (C45)",
+		.config_init    = rtl822xb_config_init,
+		.get_rate_matching = rtl822xb_get_rate_matching,
+		.config_aneg    = rtl822x_c45_config_aneg,
+		.read_status    = rtl822xb_c45_read_status,
+		.suspend        = genphy_c45_pma_suspend,
+		.resume         = rtlgen_c45_resume,
 	}, {
 		PHY_ID_MATCH_EXACT(0x001cc862),
 		.name           = "RTL8251B 5Gbps PHY",