[PATCH net-next v2 2/2] net: phy: dp83td510: Add support for the DP83TD510 Ethernet PHY

From: Oleksij Rempel
Date: Wed May 04 2022 - 07:07:15 EST


The DP83TD510E is an ultra-low power Ethernet physical layer transceiver
that supports 10M single pair cable.

This driver was tested with NXP SJA1105, STMMAC and ASIX AX88772B USB Ethernet
controller.

Signed-off-by: Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx>
---
drivers/net/phy/Kconfig | 6 +
drivers/net/phy/Makefile | 1 +
drivers/net/phy/dp83td510.c | 272 ++++++++++++++++++++++++++++++++++++
3 files changed, 279 insertions(+)
create mode 100644 drivers/net/phy/dp83td510.c

diff --git a/drivers/net/phy/Kconfig b/drivers/net/phy/Kconfig
index bbbf6c07ea53..9fee639ee5c8 100644
--- a/drivers/net/phy/Kconfig
+++ b/drivers/net/phy/Kconfig
@@ -342,6 +342,12 @@ config DP83869_PHY
Currently supports the DP83869 PHY. This PHY supports copper and
fiber connections.

+config DP83TD510_PHY
+ tristate "Texas Instruments DP83TD510 Ethernet 10Base-T1L PHY"
+ help
+ Support for the DP83TD510 Ethernet 10Base-T1L PHY. This PHY supports
+ a 10M single pair Ethernet connection for up to 1000 meter cable.
+
config VITESSE_PHY
tristate "Vitesse PHYs"
help
diff --git a/drivers/net/phy/Makefile b/drivers/net/phy/Makefile
index b82651b57043..b12b1d86fc99 100644
--- a/drivers/net/phy/Makefile
+++ b/drivers/net/phy/Makefile
@@ -57,6 +57,7 @@ obj-$(CONFIG_DP83848_PHY) += dp83848.o
obj-$(CONFIG_DP83867_PHY) += dp83867.o
obj-$(CONFIG_DP83869_PHY) += dp83869.o
obj-$(CONFIG_DP83TC811_PHY) += dp83tc811.o
+obj-$(CONFIG_DP83TD510_PHY) += dp83td510.o
obj-$(CONFIG_FIXED_PHY) += fixed_phy.o
obj-$(CONFIG_ICPLUS_PHY) += icplus.o
obj-$(CONFIG_INTEL_XWAY_PHY) += intel-xway.o
diff --git a/drivers/net/phy/dp83td510.c b/drivers/net/phy/dp83td510.c
new file mode 100644
index 000000000000..8f6b0cbed599
--- /dev/null
+++ b/drivers/net/phy/dp83td510.c
@@ -0,0 +1,272 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Driver for the Texas Instruments DP83TD510 PHY
+ * Copyright (c) 2022 Pengutronix, Oleksij Rempel <kernel@xxxxxxxxxxxxxx>
+ */
+
+#include <linux/bitfield.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/phy.h>
+
+#define DP83TD510E_PHY_ID 0x20000181
+
+/* MDIO_MMD_VEND2 registers */
+#define DP83TD510E_PHY_STS 0x10
+#define DP83TD510E_STS_MII_INT BIT(7)
+#define DP83TD510E_LINK_STATUS BIT(0)
+
+#define DP83TD510E_GEN_CFG 0x11
+#define DP83TD510E_GENCFG_INT_POLARITY BIT(3)
+#define DP83TD510E_GENCFG_INT_EN BIT(1)
+#define DP83TD510E_GENCFG_INT_OE BIT(0)
+
+#define DP83TD510E_INTERRUPT_REG_1 0x12
+#define DP83TD510E_INT1_LINK BIT(13)
+#define DP83TD510E_INT1_LINK_EN BIT(5)
+
+#define DP83TD510E_AN_STAT_1 0x60c
+#define DP83TD510E_MASTER_SLAVE_RESOL_FAIL BIT(15)
+
+static int dp83td510_config_intr(struct phy_device *phydev)
+{
+ int ret;
+
+ if (phydev->interrupts == PHY_INTERRUPT_ENABLED) {
+ /* Clear any pending interrupts */
+ ret = phy_write_mmd(phydev, MDIO_MMD_VEND2, DP83TD510E_PHY_STS,
+ 0x0);
+ if (ret)
+ return ret;
+
+ ret = phy_write_mmd(phydev, MDIO_MMD_VEND2,
+ DP83TD510E_INTERRUPT_REG_1,
+ DP83TD510E_INT1_LINK_EN);
+ if (ret)
+ return ret;
+
+ ret = phy_set_bits_mmd(phydev, MDIO_MMD_VEND2,
+ DP83TD510E_GEN_CFG,
+ DP83TD510E_GENCFG_INT_POLARITY |
+ DP83TD510E_GENCFG_INT_EN |
+ DP83TD510E_GENCFG_INT_OE);
+ } else {
+ ret = phy_write_mmd(phydev, MDIO_MMD_VEND2,
+ DP83TD510E_INTERRUPT_REG_1, 0x0);
+ if (ret)
+ return ret;
+
+ ret = phy_clear_bits_mmd(phydev, MDIO_MMD_VEND2,
+ DP83TD510E_GEN_CFG,
+ DP83TD510E_GENCFG_INT_EN);
+ if (ret)
+ return ret;
+
+ /* Clear any pending interrupts */
+ ret = phy_write_mmd(phydev, MDIO_MMD_VEND2, DP83TD510E_PHY_STS,
+ 0x0);
+ }
+
+ return ret;
+}
+
+static irqreturn_t dp83td510_handle_interrupt(struct phy_device *phydev)
+{
+ int ret;
+
+ ret = phy_read_mmd(phydev, MDIO_MMD_VEND2, DP83TD510E_PHY_STS);
+ if (ret < 0) {
+ phy_error(phydev);
+ return IRQ_NONE;
+ } else if (!(ret & DP83TD510E_STS_MII_INT)) {
+ return IRQ_NONE;
+ }
+
+ /* Read the current enabled interrupts */
+ ret = phy_read_mmd(phydev, MDIO_MMD_VEND2, DP83TD510E_INTERRUPT_REG_1);
+ if (ret < 0) {
+ phy_error(phydev);
+ return IRQ_NONE;
+ } else if (!(ret & DP83TD510E_INT1_LINK_EN) ||
+ !(ret & DP83TD510E_INT1_LINK)) {
+ return IRQ_NONE;
+ }
+
+ phy_trigger_machine(phydev);
+
+ return IRQ_HANDLED;
+}
+
+static int dp83td510_read_status(struct phy_device *phydev)
+{
+ u16 phy_sts;
+ int ret, cfg;
+
+ phydev->speed = SPEED_UNKNOWN;
+ phydev->duplex = DUPLEX_UNKNOWN;
+ phydev->pause = 0;
+ phydev->asym_pause = 0;
+ phydev->master_slave_get = MASTER_SLAVE_CFG_UNKNOWN;
+ phydev->master_slave_state = MASTER_SLAVE_STATE_UNKNOWN;
+ linkmode_zero(phydev->lp_advertising);
+
+ phy_sts = phy_read(phydev, DP83TD510E_PHY_STS);
+
+ phydev->link = !!(phy_sts & DP83TD510E_LINK_STATUS);
+ if (phydev->link) {
+ /* This PHY supports only one link mode: 10BaseT1L_Full */
+ phydev->duplex = DUPLEX_FULL;
+ phydev->speed = SPEED_10;
+
+ if (phydev->autoneg == AUTONEG_ENABLE) {
+ ret = genphy_c45_read_lpa(phydev);
+ if (ret)
+ return ret;
+
+ phy_resolve_aneg_linkmode(phydev);
+ }
+ }
+
+ if (phydev->autoneg == AUTONEG_DISABLE) {
+ ret = phy_read_mmd(phydev, MDIO_MMD_PMAPMD,
+ MDIO_PMA_PMD_BT1_CTRL);
+ if (ret < 0)
+ return ret;
+
+ if (ret & MDIO_PMA_PMD_BT1_CTRL_CFG_MST) {
+ phydev->master_slave_get =
+ MASTER_SLAVE_CFG_MASTER_FORCE;
+ if (phydev->link)
+ phydev->master_slave_state =
+ MASTER_SLAVE_STATE_MASTER;
+ } else {
+ phydev->master_slave_get = MASTER_SLAVE_CFG_SLAVE_FORCE;
+ if (phydev->link)
+ phydev->master_slave_state =
+ MASTER_SLAVE_STATE_SLAVE;
+ }
+ } else {
+ ret = phy_read_mmd(phydev, MDIO_MMD_AN, MDIO_AN_T1_ADV_L);
+ if (ret < 0)
+ return ret;
+
+ cfg = phy_read_mmd(phydev, MDIO_MMD_AN, MDIO_AN_T1_ADV_M);
+ if (cfg < 0)
+ return cfg;
+
+ if (ret & MDIO_AN_T1_ADV_L_FORCE_MS) {
+ if (cfg & MDIO_AN_T1_ADV_M_MST)
+ phydev->master_slave_get =
+ MASTER_SLAVE_CFG_MASTER_FORCE;
+ else
+ phydev->master_slave_get =
+ MASTER_SLAVE_CFG_SLAVE_FORCE;
+ } else {
+ if (cfg & MDIO_AN_T1_ADV_M_MST)
+ phydev->master_slave_get =
+ MASTER_SLAVE_CFG_MASTER_PREFERRED;
+ else
+ phydev->master_slave_get =
+ MASTER_SLAVE_CFG_SLAVE_PREFERRED;
+ }
+
+ ret = phy_read_mmd(phydev, MDIO_MMD_VEND2,
+ DP83TD510E_AN_STAT_1);
+ if (ret < 0)
+ return ret;
+
+ if (ret & DP83TD510E_MASTER_SLAVE_RESOL_FAIL)
+ phydev->master_slave_state = MASTER_SLAVE_STATE_ERR;
+ }
+
+ return 0;
+}
+
+static int dp83td510_config_master_slave(struct phy_device *phydev)
+{
+ int ctl = 0;
+
+ switch (phydev->master_slave_set) {
+ case MASTER_SLAVE_CFG_MASTER_PREFERRED:
+ case MASTER_SLAVE_CFG_MASTER_FORCE:
+ ctl = MDIO_PMA_PMD_BT1_CTRL_CFG_MST;
+ break;
+ case MASTER_SLAVE_CFG_SLAVE_FORCE:
+ case MASTER_SLAVE_CFG_SLAVE_PREFERRED:
+ break;
+ case MASTER_SLAVE_CFG_UNKNOWN:
+ case MASTER_SLAVE_CFG_UNSUPPORTED:
+ return 0;
+ default:
+ phydev_warn(phydev, "Unsupported Master/Slave mode\n");
+ return -EOPNOTSUPP;
+ }
+
+ return phy_modify_mmd(phydev, MDIO_MMD_PMAPMD, MDIO_PMA_PMD_BT1_CTRL,
+ MDIO_PMA_PMD_BT1_CTRL_CFG_MST, ctl);
+}
+
+static int dp83td510_config_aneg(struct phy_device *phydev)
+{
+ bool changed = false;
+ int ctl = 0;
+ int ret;
+
+ ret = dp83td510_config_master_slave(phydev);
+ if (ret < 0)
+ return ret;
+
+ if (phydev->autoneg == AUTONEG_DISABLE)
+ return genphy_c45_an_disable_aneg(phydev);
+
+ ret = genphy_c45_an_config_aneg(phydev);
+ if (ret < 0)
+ return ret;
+ if (ret > 0)
+ changed = true;
+
+ return genphy_c45_check_and_restart_aneg(phydev, changed);
+}
+
+static int dp83td510_get_features(struct phy_device *phydev)
+{
+ /* This PHY can't respond on MDIO bus if no RMII clock is enabled.
+ * In case RMII mode is used (most meaningful mode for this PHY) and
+ * the PHY do not have own XTAL, and CLK providing MAC is not probed,
+ * we won't be able to read all needed ability registers.
+ * So provide it manually.
+ */
+
+ linkmode_set_bit(ETHTOOL_LINK_MODE_Autoneg_BIT, phydev->supported);
+ linkmode_set_bit(ETHTOOL_LINK_MODE_Asym_Pause_BIT, phydev->supported);
+ linkmode_set_bit(ETHTOOL_LINK_MODE_Pause_BIT, phydev->supported);
+ linkmode_set_bit(ETHTOOL_LINK_MODE_10baseT1L_Full_BIT,
+ phydev->supported);
+
+ return 0;
+}
+
+static struct phy_driver dp83td510_driver[] = {
+{
+ PHY_ID_MATCH_MODEL(DP83TD510E_PHY_ID),
+ .name = "TI DP83TD510E",
+
+ .config_aneg = dp83td510_config_aneg,
+ .read_status = dp83td510_read_status,
+ .get_features = dp83td510_get_features,
+ .config_intr = dp83td510_config_intr,
+ .handle_interrupt = dp83td510_handle_interrupt,
+
+ .suspend = genphy_suspend,
+ .resume = genphy_resume,
+} };
+module_phy_driver(dp83td510_driver);
+
+static struct mdio_device_id __maybe_unused dp83td510_tbl[] = {
+ { PHY_ID_MATCH_MODEL(DP83TD510E_PHY_ID) },
+ { }
+};
+MODULE_DEVICE_TABLE(mdio, dp83td510_tbl);
+
+MODULE_DESCRIPTION("Texas Instruments DP83TD510E PHY driver");
+MODULE_AUTHOR("Oleksij Rempel <kernel@xxxxxxxxxxxxxx>");
+MODULE_LICENSE("GPL v2");
--
2.30.2