net: phy: broadcom: add support for BCM5221 phy

This patch adds the BCM5221 PHY support by reusing brcm_fet_*()
callbacks and adding quirks for BCM5221 when needed.

Cc: Jim Reinhart <jimr@tekvox.com>
Cc: James Autry <jautry@tekvox.com>
Cc: Matthew Maron <matthewm@tekvox.com>
Signed-off-by: Giulio Benetti <giulio.benetti+tekvox@benettiengineering.com>
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
Link: https://lore.kernel.org/r/20231005182915.153815-1-giulio.benetti@benettiengineering.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/phy/broadcom.c

@@ -704,11 +704,16 @@ static int brcm_fet_config_init(struct phy_device *phydev)
 	if (err < 0 && err != -EIO)
 		return err;
 
+	/* Read to clear status bits */
 	reg = phy_read(phydev, MII_BRCM_FET_INTREG);
 	if (reg < 0)
 		return reg;
 
 	/* Unmask events we are interested in and mask interrupts globally. */
+	if (phydev->phy_id == PHY_ID_BCM5221)
+		reg = MII_BRCM_FET_IR_ENABLE |
+		      MII_BRCM_FET_IR_MASK;
+	else
 		reg = MII_BRCM_FET_IR_DUPLEX_EN |
 		      MII_BRCM_FET_IR_SPEED_EN |
 		      MII_BRCM_FET_IR_LINK_EN |
@@ -726,42 +731,49 @@ static int brcm_fet_config_init(struct phy_device *phydev)
 
 	reg = brcmtest | MII_BRCM_FET_BT_SRE;
 
-	err = phy_write(phydev, MII_BRCM_FET_BRCMTEST, reg);
-	if (err < 0)
+	phy_lock_mdio_bus(phydev);
+
+	err = __phy_write(phydev, MII_BRCM_FET_BRCMTEST, reg);
+	if (err < 0) {
+		phy_unlock_mdio_bus(phydev);
 		return err;
+	}
 
+	if (phydev->phy_id != PHY_ID_BCM5221) {
 		/* Set the LED mode */
-	reg = phy_read(phydev, MII_BRCM_FET_SHDW_AUXMODE4);
+		reg = __phy_read(phydev, MII_BRCM_FET_SHDW_AUXMODE4);
 		if (reg < 0) {
 			err = reg;
 			goto done;
 		}
 
-	reg &= ~MII_BRCM_FET_SHDW_AM4_LED_MASK;
-	reg |= MII_BRCM_FET_SHDW_AM4_LED_MODE1;
-
-	err = phy_write(phydev, MII_BRCM_FET_SHDW_AUXMODE4, reg);
+		err = __phy_modify(phydev, MII_BRCM_FET_SHDW_AUXMODE4,
+				   MII_BRCM_FET_SHDW_AM4_LED_MASK,
+				   MII_BRCM_FET_SHDW_AM4_LED_MODE1);
 		if (err < 0)
 			goto done;
 
 		/* Enable auto MDIX */
-	err = phy_set_bits(phydev, MII_BRCM_FET_SHDW_MISCCTRL,
+		err = __phy_set_bits(phydev, MII_BRCM_FET_SHDW_MISCCTRL,
 				     MII_BRCM_FET_SHDW_MC_FAME);
 		if (err < 0)
 			goto done;
+	}
 
 	if (phydev->dev_flags & PHY_BRCM_AUTO_PWRDWN_ENABLE) {
 		/* Enable auto power down */
-		err = phy_set_bits(phydev, MII_BRCM_FET_SHDW_AUXSTAT2,
+		err = __phy_set_bits(phydev, MII_BRCM_FET_SHDW_AUXSTAT2,
 				     MII_BRCM_FET_SHDW_AS2_APDE);
 	}
 
 done:
 	/* Disable shadow register access */
-	err2 = phy_write(phydev, MII_BRCM_FET_BRCMTEST, brcmtest);
+	err2 = __phy_write(phydev, MII_BRCM_FET_BRCMTEST, brcmtest);
 	if (!err)
 		err = err2;
 
+	phy_unlock_mdio_bus(phydev);
+
 	return err;
 }
 
@@ -840,23 +852,86 @@ static int brcm_fet_suspend(struct phy_device *phydev)
 
 	reg = brcmtest | MII_BRCM_FET_BT_SRE;
 
-	err = phy_write(phydev, MII_BRCM_FET_BRCMTEST, reg);
-	if (err < 0)
+	phy_lock_mdio_bus(phydev);
+
+	err = __phy_write(phydev, MII_BRCM_FET_BRCMTEST, reg);
+	if (err < 0) {
+		phy_unlock_mdio_bus(phydev);
 		return err;
+	}
 
+	if (phydev->phy_id == PHY_ID_BCM5221)
+		/* Force Low Power Mode with clock enabled */
+		reg = BCM5221_SHDW_AM4_EN_CLK_LPM | BCM5221_SHDW_AM4_FORCE_LPM;
+	else
 		/* Set standby mode */
-	err = phy_modify(phydev, MII_BRCM_FET_SHDW_AUXMODE4,
-			 MII_BRCM_FET_SHDW_AM4_STANDBY,
-			 MII_BRCM_FET_SHDW_AM4_STANDBY);
+		reg = MII_BRCM_FET_SHDW_AM4_STANDBY;
+
+	err = __phy_set_bits(phydev, MII_BRCM_FET_SHDW_AUXMODE4, reg);
 
 	/* Disable shadow register access */
-	err2 = phy_write(phydev, MII_BRCM_FET_BRCMTEST, brcmtest);
+	err2 = __phy_write(phydev, MII_BRCM_FET_BRCMTEST, brcmtest);
 	if (!err)
 		err = err2;
 
+	phy_unlock_mdio_bus(phydev);
+
 	return err;
 }
 
+static int bcm5221_config_aneg(struct phy_device *phydev)
+{
+	int ret, val;
+
+	ret = genphy_config_aneg(phydev);
+	if (ret)
+		return ret;
+
+	switch (phydev->mdix_ctrl) {
+	case ETH_TP_MDI:
+		val = BCM5221_AEGSR_MDIX_DIS;
+		break;
+	case ETH_TP_MDI_X:
+		val = BCM5221_AEGSR_MDIX_DIS | BCM5221_AEGSR_MDIX_MAN_SWAP;
+		break;
+	case ETH_TP_MDI_AUTO:
+		val = 0;
+		break;
+	default:
+		return 0;
+	}
+
+	return phy_modify(phydev, BCM5221_AEGSR, BCM5221_AEGSR_MDIX_MAN_SWAP |
+						 BCM5221_AEGSR_MDIX_DIS,
+						 val);
+}
+
+static int bcm5221_read_status(struct phy_device *phydev)
+{
+	int ret;
+
+	/* Read MDIX status */
+	ret = phy_read(phydev, BCM5221_AEGSR);
+	if (ret < 0)
+		return ret;
+
+	if (ret & BCM5221_AEGSR_MDIX_DIS) {
+		if (ret & BCM5221_AEGSR_MDIX_MAN_SWAP)
+			phydev->mdix_ctrl = ETH_TP_MDI_X;
+		else
+			phydev->mdix_ctrl = ETH_TP_MDI;
+	} else {
+		phydev->mdix_ctrl = ETH_TP_MDI_AUTO;
+	}
+
+	if (ret & BCM5221_AEGSR_MDIX_STATUS)
+		phydev->mdix = ETH_TP_MDI_X;
+	else
+		phydev->mdix = ETH_TP_MDI;
+
+	return genphy_read_status(phydev);
+}
+
 static void bcm54xx_phy_get_wol(struct phy_device *phydev,
 				struct ethtool_wolinfo *wol)
 {
@@ -1221,6 +1296,18 @@ static struct phy_driver broadcom_drivers[] = {
 	.handle_interrupt = brcm_fet_handle_interrupt,
 	.suspend	= brcm_fet_suspend,
 	.resume		= brcm_fet_config_init,
+}, {
+	.phy_id		= PHY_ID_BCM5221,
+	.phy_id_mask	= 0xfffffff0,
+	.name		= "Broadcom BCM5221",
+	/* PHY_BASIC_FEATURES */
+	.config_init	= brcm_fet_config_init,
+	.config_intr	= brcm_fet_config_intr,
+	.handle_interrupt = brcm_fet_handle_interrupt,
+	.suspend	= brcm_fet_suspend,
+	.resume		= brcm_fet_config_init,
+	.config_aneg	= bcm5221_config_aneg,
+	.read_status	= bcm5221_read_status,
 }, {
 	.phy_id		= PHY_ID_BCM5395,
 	.phy_id_mask	= 0xfffffff0,
@@ -1296,6 +1383,7 @@ static struct mdio_device_id __maybe_unused broadcom_tbl[] = {
 	{ PHY_ID_BCM50610M, 0xfffffff0 },
 	{ PHY_ID_BCM57780, 0xfffffff0 },
 	{ PHY_ID_BCMAC131, 0xfffffff0 },
+	{ PHY_ID_BCM5221, 0xfffffff0 },
 	{ PHY_ID_BCM5241, 0xfffffff0 },
 	{ PHY_ID_BCM5395, 0xfffffff0 },
 	{ PHY_ID_BCM53125, 0xfffffff0 },

include/linux/brcmphy.h

@@ -11,6 +11,7 @@
 
 #define PHY_ID_BCM50610			0x0143bd60
 #define PHY_ID_BCM50610M		0x0143bd70
+#define PHY_ID_BCM5221			0x004061e0
 #define PHY_ID_BCM5241			0x0143bc30
 #define PHY_ID_BCMAC131			0x0143bc70
 #define PHY_ID_BCM5481			0x0143bca0
@@ -331,6 +332,15 @@
 
 #define BCM54XX_WOL_INT_STATUS		(MII_BCM54XX_EXP_SEL_WOL + 0x94)
 
+/* BCM5221 Registers */
+#define BCM5221_AEGSR			0x1C
+#define BCM5221_AEGSR_MDIX_STATUS	BIT(13)
+#define BCM5221_AEGSR_MDIX_MAN_SWAP	BIT(12)
+#define BCM5221_AEGSR_MDIX_DIS		BIT(11)
+
+#define BCM5221_SHDW_AM4_EN_CLK_LPM	BIT(2)
+#define BCM5221_SHDW_AM4_FORCE_LPM	BIT(1)
+
 /*****************************************************************************/
 /* Fast Ethernet Transceiver definitions. */
 /*****************************************************************************/