[RFC v3 4/4] net: dsa: initial support for MT7628 embedded switch

[Joris Vaisvila <joey@tinyisr.com>]

Add support for the MT7628 embedded switch.

The switch has 5 built-in 100Mbps user ports (ports 0-4) and one 1Gbps
port that is internally attached to the SoCs CPU MAC and serves as the
CPU port.

The switch hardware has a very limited 16 entry VLAN table. Configuring
VLANs is the only way to control switch forwarding. Currently 6 entries
are used by tag_8021q to isolate the ports. Double tag feature is
enabled to force the switch to append the VLAN tag even if the incoming
packet is already tagged, this simulates VLAN-unaware functionality and
simplifies the tagger implementation.

Signed-off-by: Joris Vaisvila <joey@tinyisr.com>
---
 drivers/net/dsa/Kconfig  |   7 +
 drivers/net/dsa/Makefile |   1 +
 drivers/net/dsa/mt7628.c | 634 +++++++++++++++++++++++++++++++++++++++
 3 files changed, 642 insertions(+)
 create mode 100644 drivers/net/dsa/mt7628.c

diff --git a/drivers/net/dsa/Kconfig b/drivers/net/dsa/Kconfig
index 39fb8ead16b5..d07fc8dfe228 100644
--- a/drivers/net/dsa/Kconfig
+++ b/drivers/net/dsa/Kconfig
@@ -70,6 +70,13 @@ config NET_DSA_MV88E6060
 	  This enables support for the Marvell 88E6060 ethernet switch
 	  chip.
 
+config NET_DSA_MT7628
+	tristate "MT7628 Embedded ethernet switch support"
+	select NET_DSA_TAG_MT7628
+	select MEDIATEK_FE_SOC_PHY
+	help
+	  This enables support for the switch in the MT7628 SoC.
+
 source "drivers/net/dsa/microchip/Kconfig"
 
 source "drivers/net/dsa/mv88e6xxx/Kconfig"
diff --git a/drivers/net/dsa/Makefile b/drivers/net/dsa/Makefile
index f5a463b87ec2..22da6b680f29 100644
--- a/drivers/net/dsa/Makefile
+++ b/drivers/net/dsa/Makefile
@@ -15,6 +15,7 @@ obj-$(CONFIG_NET_DSA_VITESSE_VSC73XX) += vitesse-vsc73xx-core.o
 obj-$(CONFIG_NET_DSA_VITESSE_VSC73XX_PLATFORM) += vitesse-vsc73xx-platform.o
 obj-$(CONFIG_NET_DSA_VITESSE_VSC73XX_SPI) += vitesse-vsc73xx-spi.o
 obj-$(CONFIG_NET_DSA_YT921X) += yt921x.o
+obj-$(CONFIG_NET_DSA_MT7628) += mt7628.o
 obj-y				+= b53/
 obj-y				+= hirschmann/
 obj-y				+= lantiq/
diff --git a/drivers/net/dsa/mt7628.c b/drivers/net/dsa/mt7628.c
new file mode 100644
index 000000000000..91b457ab096b
--- /dev/null
+++ b/drivers/net/dsa/mt7628.c
@@ -0,0 +1,634 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Mediatek MT7628 Embedded Switch (ESW) DSA driver
+ * Copyright (C) 2026 Joris Vaisvila <joey@tinyisr.com>
+ *
+ * Portions derived from OpenWRT esw_rt3050 driver:
+ * Copyright (C) 2009-2015 John Crispin <blogic@openwrt.org>
+ * Copyright (C) 2009-2015 Felix Fietkau <nbd@nbd.name>
+ * Copyright (C) 2013-2015 Michael Lee <igvtee@gmail.com>
+ * Copyright (C) 2016 Vittorio Gambaletta <openwrt@vittgam.net>
+ */
+
+#include <linux/platform_device.h>
+#include <linux/etherdevice.h>
+#include <linux/netdevice.h>
+#include <linux/dsa/8021q.h>
+#include <linux/if_bridge.h>
+#include <linux/module.h>
+#include <linux/mdio.h>
+#include <linux/of.h>
+#include <linux/of_mdio.h>
+#include <linux/of_net.h>
+#include <linux/kernel.h>
+#include <linux/regmap.h>
+#include <linux/reset.h>
+#include <net/dsa.h>
+
+#define MT7628_ESW_REG_IMR 0x04
+#define MT7628_ESW_REG_FCT0 0x08
+#define MT7628_ESW_REG_PFC1 0x14
+#define MT7628_ESW_REG_PVIDC(port) (0x40 + 4 * ((port) / 2))
+#define MT7628_ESW_REG_VLANI(vlan) (0x50 + 4 * ((vlan) / 2))
+#define MT7628_ESW_REG_VMSC(vlan) (0x70 + 4 * ((vlan) / 4))
+#define MT7628_ESW_REG_VUB(vlan) (0x100 + 4 * ((vlan) / 4))
+#define MT7628_ESW_REG_SOCPC 0x8c
+#define MT7628_ESW_REG_POC0 0x90
+#define MT7628_ESW_REG_POC2 0x98
+#define MT7628_ESW_REG_SGC 0x9c
+#define MT7628_ESW_REG_PCR0 0xc0
+#define MT7628_ESW_REG_PCR1 0xc4
+#define MT7628_ESW_REG_FPA2 0xc8
+#define MT7628_ESW_REG_FCT2 0xcc
+#define MT7628_ESW_REG_SGC2 0xe4
+
+#define MT7628_ESW_FCT0_DROP_SET_TH GENMASK(7, 0)
+#define MT7628_ESW_FCT0_DROP_RLS_TH GENMASK(15, 8)
+#define MT7628_ESW_FCT0_FC_SET_TH GENMASK(23, 16)
+#define MT7628_ESW_FCT0_FC_RLS_TH GENMASK(31, 24)
+
+#define MT7628_ESW_PFC1_EN_VLAN GENMASK(22, 16)
+
+#define MT7628_ESW_PVID_S 12
+#define MT7628_ESW_PVID_M GENMASK(11, 0)
+#define MT7628_ESW_PVID_SHIFT(port) \
+	(MT7628_ESW_PVID_S * ((port) % 2))
+#define MT7628_ESW_PVID_MASK(port) \
+	(MT7628_ESW_PVID_M << MT7628_ESW_PVID_SHIFT(port))
+#define MT7628_ESW_PVID_PREP(port, pvid) \
+	(((pvid) & MT7628_ESW_PVID_M) << MT7628_ESW_PVID_SHIFT(port))
+
+#define MT7628_ESW_VID_S 12
+#define MT7628_ESW_VID_M GENMASK(11, 0)
+#define MT7628_ESW_VID_SHIFT(vlan) \
+	(MT7628_ESW_VID_S * ((vlan) % 2))
+#define MT7628_ESW_VID_MASK(vlan) \
+	(MT7628_ESW_VID_M << MT7628_ESW_VID_SHIFT(vlan))
+#define MT7628_ESW_VID_PREP(vlan, vid) \
+	(((vid) & MT7628_ESW_VID_M) << MT7628_ESW_VID_SHIFT(vlan))
+
+#define MT7628_ESW_VMSC_S 8
+#define MT7628_ESW_VMSC_M GENMASK(7, 0)
+#define MT7628_ESW_VMSC_SHIFT(vlan) \
+	(MT7628_ESW_VMSC_S * ((vlan) % 4))
+#define MT7628_ESW_VMSC_MASK(vlan) \
+	(MT7628_ESW_VMSC_M << MT7628_ESW_VMSC_SHIFT(vlan))
+#define MT7628_ESW_VMSC_PREP(vlan, vmsc) \
+	(((vmsc) & MT7628_ESW_VMSC_M) << MT7628_ESW_VMSC_SHIFT(vlan))
+
+#define MT7628_ESW_VUB_S 7
+#define MT7628_ESW_VUB_M GENMASK(6, 0)
+#define MT7628_ESW_VUB_SHIFT(vlan) \
+	(MT7628_ESW_VUB_S * ((vlan) % 4))
+#define MT7628_ESW_VUB_MASK(vlan) \
+	(MT7628_ESW_VUB_M << MT7628_ESW_VUB_SHIFT(vlan))
+#define MT7628_ESW_VUB_PREP(vlan, vub) \
+	(((vub) & MT7628_ESW_VUB_M) << MT7628_ESW_VUB_SHIFT(vlan))
+
+#define MT7628_ESW_SOCPC_CRC_PADDING BIT(25)
+#define MT7628_ESW_SOCPC_DISBC2CPU GENMASK(22, 16)
+#define MT7628_ESW_SOCPC_DISMC2CPU GENMASK(14, 8)
+#define MT7628_ESW_SOCPC_DISUN2CPU GENMASK(6, 0)
+
+#define MT7628_ESW_POC0_PORT_DISABLE GENMASK(29, 23)
+
+#define MT7628_ESW_POC2_PER_VLAN_UNTAG_EN BIT(15)
+
+#define MT7628_ESW_SGC_AGING_INTERVAL GENMASK(3, 0)
+#define MT7628_ESW_BC_STORM_PROT GENMASK(5, 4)
+#define MT7628_ESW_PKT_MAX_LEN GENMASK(7, 6)
+#define MT7628_ESW_DIS_PKT_ABORT BIT(8)
+#define MT7628_ESW_ADDRESS_HASH_ALG GENMASK(10, 9)
+#define MT7628_ESW_DISABLE_TX_BACKOFF BIT(11)
+#define MT7628_ESW_BP_JAM_CNT GENMASK(15, 12)
+#define MT7628_ESW_DISMIIPORT_WASTX GENMASK(17, 16)
+#define MT7628_ESW_BP_MODE GENMASK(19, 18)
+#define MT7628_ESW_BISH_DIS BIT(20)
+#define MT7628_ESW_BISH_TH GENMASK(22, 21)
+#define MT7628_ESW_LED_FLASH_TIME GENMASK(24, 23)
+#define MT7628_ESW_RMC_RULE GENMASK(26, 25)
+#define MT7628_ESW_IP_MULT_RULE GENMASK(28, 27)
+#define MT7628_ESW_LEN_ERR_CHK BIT(29)
+#define MT7628_ESW_BKOFF_ALG BIT(30)
+
+#define MT7628_ESW_PCR0_WT_NWAY_DATA GENMASK(31, 16)
+#define MT7628_ESW_PCR0_RD_PHY_CMD BIT(14)
+#define MT7628_ESW_PCR0_WT_PHY_CMD BIT(13)
+#define MT7628_ESW_PCR0_CPU_PHY_REG GENMASK(12, 8)
+#define MT7628_ESW_PCR0_CPU_PHY_ADDR GENMASK(4, 0)
+
+#define MT7628_ESW_PCR1_RD_DATA GENMASK(31, 16)
+#define MT7628_ESW_PCR1_RD_DONE BIT(1)
+#define MT7628_ESW_PCR1_WT_DONE BIT(0)
+
+#define MT7628_ESW_FPA2_AP_EN BIT(29)
+#define MT7628_ESW_FPA2_EXT_PHY_ADDR_BASE GENMASK(28, 24)
+#define MT7628_ESW_FPA2_FORCE_RGMII_LINK1 BIT(13)
+#define MT7628_ESW_FPA2_FORCE_RGMII_EN1 BIT(11)
+
+#define MT7628_ESW_FCT2_MUST_DROP_RLS_TH GENMASK(17, 13)
+#define MT7628_ESW_FCT2_MUST_DROP_SET_TH GENMASK(12, 8)
+#define MT7628_ESW_FCT2_MC_PER_PORT_TH GENMASK(5, 0)
+
+#define MT7628_ESW_SGC2_SPECIAL_TAG_EN BIT(23)
+#define MT7628_ESW_SGC2_TX_CPU_TPID_BIT_MAP GENMASK(22, 16)
+#define MT7628_ESW_SGC2_DOUBLE_TAG_EN GENMASK(6, 0)
+
+#define MT7628_ESW_PORTS_NOCPU GENMASK(5, 0)
+#define MT7628_ESW_PORTS_CPU BIT(6)
+#define MT7628_ESW_PORTS_ALL GENMASK(6, 0)
+
+#define MT7628_ESW_NUM_PORTS 7
+#define MT7628_NUM_VLANS 16
+
+static const struct regmap_config mt7628_esw_regmap_cfg = {
+	.name = "mt7628-esw",
+	.reg_bits = 32,
+	.val_bits = 32,
+	.reg_stride = 4,
+	.fast_io = true,
+	.reg_format_endian = REGMAP_ENDIAN_LITTLE,
+	.val_format_endian = REGMAP_ENDIAN_LITTLE,
+};
+
+struct mt7628_vlan {
+	bool active;
+	u8 members;
+	u8 untag;
+	u16 vid;
+};
+
+struct mt7628_esw {
+	void __iomem *base;
+	struct reset_control *rst_ephy;
+	struct reset_control *rst_esw;
+	struct regmap *regmap;
+	struct dsa_switch *ds;
+	u16 tag_8021q_pvid[MT7628_ESW_NUM_PORTS];
+	struct mt7628_vlan vlans[MT7628_NUM_VLANS];
+	struct device *dev;
+};
+
+static int mt7628_mii_read(struct mii_bus *bus, int port, int regnum)
+{
+	struct mt7628_esw *esw = bus->priv;
+	int ret;
+	u32 val;
+
+	ret = regmap_read_poll_timeout(esw->regmap, MT7628_ESW_REG_PCR1, val,
+				       !(val & MT7628_ESW_PCR1_RD_DONE), 10,
+				       5000);
+	if (ret)
+		goto out;
+
+	ret = regmap_write(esw->regmap, MT7628_ESW_REG_PCR0,
+			   FIELD_PREP(MT7628_ESW_PCR0_CPU_PHY_REG,
+				      regnum) |
+			   FIELD_PREP(MT7628_ESW_PCR0_CPU_PHY_ADDR,
+				      port) | MT7628_ESW_PCR0_RD_PHY_CMD);
+	if (ret)
+		goto out;
+
+	ret = regmap_read_poll_timeout(esw->regmap, MT7628_ESW_REG_PCR1, val,
+				       (val & MT7628_ESW_PCR1_RD_DONE), 10,
+				       5000);
+out:
+	if (ret) {
+		dev_err(&bus->dev, "read failed. MDIO timeout?\n");
+		return -ETIMEDOUT;
+	}
+	return FIELD_GET(MT7628_ESW_PCR1_RD_DATA, val);
+}
+
+static int mt7628_mii_write(struct mii_bus *bus, int port, int regnum, u16 dat)
+{
+	struct mt7628_esw *esw = bus->priv;
+	u32 val;
+	int ret;
+
+	ret = regmap_read_poll_timeout(esw->regmap, MT7628_ESW_REG_PCR1, val,
+				       !(val & MT7628_ESW_PCR1_WT_DONE), 10,
+				       5000);
+	if (ret)
+		goto out;
+
+	ret = regmap_write(esw->regmap, MT7628_ESW_REG_PCR0,
+			   FIELD_PREP(MT7628_ESW_PCR0_WT_NWAY_DATA, dat) |
+			   FIELD_PREP(MT7628_ESW_PCR0_CPU_PHY_REG,
+				      regnum) |
+			   FIELD_PREP(MT7628_ESW_PCR0_CPU_PHY_ADDR,
+				      port) | MT7628_ESW_PCR0_WT_PHY_CMD);
+	if (ret)
+		goto out;
+
+	ret = regmap_read_poll_timeout(esw->regmap, MT7628_ESW_REG_PCR1, val,
+				       (val & MT7628_ESW_PCR1_WT_DONE), 10,
+				       5000);
+out:
+	if (ret) {
+		dev_err(&bus->dev, "write failed. MDIO timeout?\n");
+		return -ETIMEDOUT;
+	}
+	return ret;
+}
+
+static int mt7628_setup_internal_mdio(struct dsa_switch *ds,
+				      struct device_node *node)
+{
+	struct mt7628_esw *esw = ds->priv;
+	struct mii_bus *bus;
+	int ret;
+
+	bus = devm_mdiobus_alloc(esw->dev);
+	if (!bus)
+		return -ENOMEM;
+
+	bus->name = "MT7628 internal MDIO bus";
+	snprintf(bus->id, MII_BUS_ID_SIZE, "%s-mii", dev_name(ds->dev));
+	bus->priv = esw;
+	bus->read = mt7628_mii_read;
+	bus->write = mt7628_mii_write;
+	bus->parent = esw->dev;
+
+	ret = devm_of_mdiobus_register(esw->dev, bus, node);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+static void mt7628_switch_init(struct dsa_switch *ds)
+{
+	struct mt7628_esw *esw = ds->priv;
+
+	regmap_write(esw->regmap, MT7628_ESW_REG_FCT0,
+		     FIELD_PREP(MT7628_ESW_FCT0_DROP_SET_TH, 0x50) |
+		     FIELD_PREP(MT7628_ESW_FCT0_DROP_RLS_TH, 0x78) |
+		     FIELD_PREP(MT7628_ESW_FCT0_FC_SET_TH, 0xa0) |
+		     FIELD_PREP(MT7628_ESW_FCT0_FC_RLS_TH, 0xc8));
+
+	regmap_write(esw->regmap, MT7628_ESW_REG_FCT2,
+		     FIELD_PREP(MT7628_ESW_FCT2_MC_PER_PORT_TH, 0xc) |
+		     FIELD_PREP(MT7628_ESW_FCT2_MUST_DROP_SET_TH, 0x10) |
+		     FIELD_PREP(MT7628_ESW_FCT2_MUST_DROP_RLS_TH, 0x12));
+
+	/*
+	 * general switch configuration:
+	 * 300s aging interval
+	 * broadcast storm prevention disabled
+	 * max packet length 1536 bytes
+	 * disable collision 16 packet abort and late collision abort
+	 * use xor48 for address hashing
+	 * disable tx backoff
+	 * 10 packet back pressure jam
+	 * disable was_transmit
+	 * jam until BP condition released
+	 * 30ms LED flash
+	 * rmc tb fault to all ports
+	 * unmatched IGMP as broadcast
+	 */
+	regmap_write(esw->regmap, MT7628_ESW_REG_SGC,
+		     FIELD_PREP(MT7628_ESW_SGC_AGING_INTERVAL, 1) |
+		     FIELD_PREP(MT7628_ESW_BC_STORM_PROT, 0) |
+		     FIELD_PREP(MT7628_ESW_PKT_MAX_LEN, 0) |
+		     MT7628_ESW_DIS_PKT_ABORT |
+		     FIELD_PREP(MT7628_ESW_ADDRESS_HASH_ALG, 1) |
+		     MT7628_ESW_DISABLE_TX_BACKOFF |
+		     FIELD_PREP(MT7628_ESW_BP_JAM_CNT, 10) |
+		     FIELD_PREP(MT7628_ESW_DISMIIPORT_WASTX, 0) |
+		     FIELD_PREP(MT7628_ESW_BP_MODE, 0b10) |
+		     FIELD_PREP(MT7628_ESW_LED_FLASH_TIME, 0) |
+		     FIELD_PREP(MT7628_ESW_RMC_RULE, 0) |
+		     FIELD_PREP(MT7628_ESW_IP_MULT_RULE, 0));
+
+	regmap_write(esw->regmap, MT7628_ESW_REG_SOCPC,
+		     MT7628_ESW_SOCPC_CRC_PADDING |
+		     FIELD_PREP(MT7628_ESW_SOCPC_DISUN2CPU,
+				MT7628_ESW_PORTS_CPU) |
+		     FIELD_PREP(MT7628_ESW_SOCPC_DISMC2CPU,
+				MT7628_ESW_PORTS_CPU) |
+		     FIELD_PREP(MT7628_ESW_SOCPC_DISBC2CPU,
+				MT7628_ESW_PORTS_CPU));
+
+	regmap_set_bits(esw->regmap, MT7628_ESW_REG_FPA2,
+			MT7628_ESW_FPA2_FORCE_RGMII_EN1 |
+			MT7628_ESW_FPA2_FORCE_RGMII_LINK1 |
+			MT7628_ESW_FPA2_AP_EN);
+
+	regmap_update_bits(esw->regmap, MT7628_ESW_REG_FPA2,
+			   MT7628_ESW_FPA2_EXT_PHY_ADDR_BASE,
+			   FIELD_PREP(MT7628_ESW_FPA2_EXT_PHY_ADDR_BASE, 31));
+
+	/* disable all interrupts */
+	regmap_write(esw->regmap, MT7628_ESW_REG_IMR, 0);
+
+	/* enable MT7628 DSA tag on CPU port */
+	regmap_write(esw->regmap, MT7628_ESW_REG_SGC2,
+		     MT7628_ESW_SGC2_SPECIAL_TAG_EN |
+		     FIELD_PREP(MT7628_ESW_SGC2_TX_CPU_TPID_BIT_MAP,
+				MT7628_ESW_PORTS_CPU));
+
+	/*
+	 * Double tag feature allows switch to always append the port PVID VLAN tag
+	 * regardless of if the incoming packet already has a VLAN tag.
+	 * This is enabled to simulate VLAN unawareness.
+	 */
+	regmap_set_bits(esw->regmap, MT7628_ESW_REG_SGC2,
+			FIELD_PREP(MT7628_ESW_SGC2_DOUBLE_TAG_EN,
+				   MT7628_ESW_PORTS_NOCPU));
+
+	regmap_set_bits(esw->regmap, MT7628_ESW_REG_POC2,
+			MT7628_ESW_POC2_PER_VLAN_UNTAG_EN);
+
+	regmap_update_bits(esw->regmap, MT7628_ESW_REG_PFC1,
+			   MT7628_ESW_PFC1_EN_VLAN,
+			   FIELD_PREP(MT7628_ESW_PFC1_EN_VLAN,
+				      MT7628_ESW_PORTS_ALL));
+}
+
+static void mt7628_esw_set_pvid(struct mt7628_esw *esw, unsigned int port,
+				unsigned int pvid)
+{
+	regmap_update_bits(esw->regmap, MT7628_ESW_REG_PVIDC(port),
+			   MT7628_ESW_PVID_MASK(port),
+			   MT7628_ESW_PVID_PREP(port, pvid));
+}
+
+static void mt7628_esw_set_vlan_id(struct mt7628_esw *esw, unsigned int vlan,
+				   unsigned int vid)
+{
+	regmap_update_bits(esw->regmap, MT7628_ESW_REG_VLANI(vlan),
+			   MT7628_ESW_VID_MASK(vlan),
+			   MT7628_ESW_VID_PREP(vlan, vid));
+}
+
+static void mt7628_esw_set_vmsc(struct mt7628_esw *esw, unsigned int vlan,
+				unsigned int msc)
+{
+	regmap_update_bits(esw->regmap, MT7628_ESW_REG_VMSC(vlan),
+			   MT7628_ESW_VMSC_MASK(vlan),
+			   MT7628_ESW_VMSC_PREP(vlan, msc));
+}
+
+static void mt7628_esw_set_vub(struct mt7628_esw *esw, unsigned int vlan,
+			       unsigned int vub)
+{
+	regmap_update_bits(esw->regmap, MT7628_ESW_REG_VUB(vlan),
+			   MT7628_ESW_VUB_MASK(vlan),
+			   MT7628_ESW_VUB_PREP(vlan, vub));
+}
+
+static void mt7628_vlan_sync(struct dsa_switch *ds)
+{
+	struct mt7628_esw *esw = ds->priv;
+	int i;
+
+	for (i = 0; i < MT7628_NUM_VLANS; i++) {
+		struct mt7628_vlan *vlan = &esw->vlans[i];
+
+		mt7628_esw_set_vmsc(esw, i, vlan->members);
+		mt7628_esw_set_vlan_id(esw, i, vlan->vid);
+		mt7628_esw_set_vub(esw, i, vlan->untag);
+	}
+
+	for (i = 0; i < ds->num_ports; i++)
+		mt7628_esw_set_pvid(esw, i, esw->tag_8021q_pvid[i]);
+}
+
+static int mt7628_setup(struct dsa_switch *ds)
+{
+	struct mt7628_esw *esw = ds->priv;
+	struct device_node *child;
+	int ret;
+
+	reset_control_reset(esw->rst_esw);
+	usleep_range(1000, 2000);
+	reset_control_reset(esw->rst_ephy);
+	usleep_range(1000, 2000);
+	/*
+	 * all MMIO reads hang if esw is not out of reset
+	 * ephy needs extra time to get out of reset or it ends up misconfigured
+	 */
+	mt7628_switch_init(ds);
+	rtnl_lock();
+	dsa_tag_8021q_register(ds, htons(ETH_P_8021Q));
+	rtnl_unlock();
+
+	child = of_get_child_by_name(ds->dev->of_node, "mdio");
+	if (child) {
+		ret = mt7628_setup_internal_mdio(ds, child);
+		of_node_put(child);
+		if (ret)
+			return ret;
+	}
+	return 0;
+}
+
+static int mt7628_port_enable(struct dsa_switch *ds, int port,
+			      struct phy_device *phy)
+{
+	struct mt7628_esw *esw = ds->priv;
+
+	regmap_clear_bits(esw->regmap, MT7628_ESW_REG_POC0,
+			  FIELD_PREP(MT7628_ESW_POC0_PORT_DISABLE, BIT(port)));
+	return 0;
+}
+
+static void mt7628_port_disable(struct dsa_switch *ds, int port)
+{
+	struct mt7628_esw *esw = ds->priv;
+
+	regmap_set_bits(esw->regmap, MT7628_ESW_REG_POC0,
+			FIELD_PREP(MT7628_ESW_POC0_PORT_DISABLE, BIT(port)));
+}
+
+static enum dsa_tag_protocol
+mt7628_get_tag_proto(struct dsa_switch *ds, int port, enum dsa_tag_protocol mp)
+{
+	return DSA_TAG_PROTO_MT7628;
+}
+
+static void mt7628_phylink_get_caps(struct dsa_switch *ds, int port,
+				    struct phylink_config *config)
+{
+	switch (port) {
+	case 0:
+	case 1:
+	case 2:
+	case 3:
+	case 4:
+		config->mac_capabilities = MAC_100 | MAC_10;
+		__set_bit(PHY_INTERFACE_MODE_INTERNAL,
+			  config->supported_interfaces);
+		break;
+	case 6:
+		config->mac_capabilities = MAC_1000 | MAC_100 | MAC_10;
+		__set_bit(PHY_INTERFACE_MODE_RGMII,
+			  config->supported_interfaces);
+		break;
+	case 5:
+	default:
+		/* Port 5 does not exist on MT7628; other ports are invalid */
+		return;
+	}
+}
+
+static int mt7628_dsa_8021q_vlan_add(struct dsa_switch *ds, int port,
+				     u16 vid, u16 flags)
+{
+	struct mt7628_esw *esw = ds->priv;
+	struct mt7628_vlan *vlan = NULL;
+	int i;
+
+	for (i = 0; i < MT7628_NUM_VLANS; i++) {
+		struct mt7628_vlan *check_vlan = &esw->vlans[i];
+
+		if (!check_vlan->active && !vlan) {
+			vlan = check_vlan;
+		} else if (check_vlan->vid == vid) {
+			vlan = check_vlan;
+			break;
+		}
+	}
+
+	if (!vlan)
+		return -ENOSPC;
+
+	vlan->vid = vid;
+	vlan->active = true;
+	vlan->members |= BIT(port);
+
+	if (flags & BRIDGE_VLAN_INFO_PVID)
+		esw->tag_8021q_pvid[port] = vid;
+
+	if (flags & BRIDGE_VLAN_INFO_UNTAGGED)
+		vlan->untag |= BIT(port);
+
+	mt7628_vlan_sync(ds);
+	return 0;
+}
+
+static int mt7628_dsa_8021q_vlan_del(struct dsa_switch *ds, int port, u16 vid)
+{
+	struct mt7628_esw *esw = ds->priv;
+	struct mt7628_vlan *vlan = NULL;
+	int i;
+
+	for (i = 0; i < MT7628_NUM_VLANS; i++) {
+		struct mt7628_vlan *check_vlan = &esw->vlans[i];
+
+		if (!check_vlan->active || check_vlan->vid != vid)
+			continue;
+		vlan = check_vlan;
+		break;
+	}
+	if (!vlan)
+		return -ENOENT;
+
+	vlan->members &= ~BIT(port);
+	vlan->untag &= ~BIT(port);
+
+	if (!vlan->members)
+		vlan->active = false;
+
+	mt7628_vlan_sync(ds);
+	return 0;
+}
+
+static struct dsa_switch_ops mt7628_switch_ops = {
+	.get_tag_protocol = mt7628_get_tag_proto,
+	.setup = mt7628_setup,
+	.port_enable = mt7628_port_enable,
+	.port_disable = mt7628_port_disable,
+	.phylink_get_caps = mt7628_phylink_get_caps,
+	.tag_8021q_vlan_add = mt7628_dsa_8021q_vlan_add,
+	.tag_8021q_vlan_del = mt7628_dsa_8021q_vlan_del,
+};
+
+static int mt7628_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct mt7628_esw *esw;
+	struct dsa_switch *ds;
+
+	ds = devm_kzalloc(&pdev->dev, sizeof(*ds), GFP_KERNEL);
+	if (!ds)
+		return -ENOMEM;
+
+	esw = devm_kzalloc(&pdev->dev, sizeof(*esw), GFP_KERNEL);
+	if (!esw)
+		return -ENOMEM;
+
+	esw->base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(esw->base))
+		return PTR_ERR(esw->base);
+
+	esw->regmap = devm_regmap_init_mmio(&pdev->dev, esw->base,
+					    &mt7628_esw_regmap_cfg);
+	if (IS_ERR(esw->regmap))
+		return PTR_ERR(esw->regmap);
+
+	esw->rst_ephy = devm_reset_control_get_exclusive(&pdev->dev, "ephy");
+	if (IS_ERR(esw->rst_ephy))
+		return dev_err_probe(dev, PTR_ERR(esw->rst_ephy),
+				     "failed to get EPHY reset\n");
+
+	esw->rst_esw = devm_reset_control_get_exclusive(&pdev->dev, "esw");
+	if (IS_ERR(esw->rst_esw))
+		return dev_err_probe(dev, PTR_ERR(esw->rst_esw),
+				     "failed to get ESW reset\n");
+
+	ds->dev = dev;
+	ds->num_ports = MT7628_ESW_NUM_PORTS;
+	ds->ops = &mt7628_switch_ops;
+	ds->priv = esw;
+	esw->ds = ds;
+	esw->dev = dev;
+	dev_set_drvdata(dev, esw);
+
+	return dsa_register_switch(ds);
+}
+
+static void mt7628_remove(struct platform_device *pdev)
+{
+	struct mt7628_esw *esw = platform_get_drvdata(pdev);
+
+	if (!esw)
+		return;
+
+	dsa_unregister_switch(esw->ds);
+}
+
+static void mt7628_shutdown(struct platform_device *pdev)
+{
+	struct mt7628_esw *esw = platform_get_drvdata(pdev);
+
+	if (!esw)
+		return;
+
+	dsa_switch_shutdown(esw->ds);
+	dev_set_drvdata(&pdev->dev, NULL);
+}
+
+static const struct of_device_id mt7628_of_match[] = {
+	{ .compatible = "mediatek,mt7628-esw" },
+	{}
+};
+
+MODULE_DEVICE_TABLE(of, mt7628_of_match);
+
+static struct platform_driver mt7628_driver = {
+	.driver = {
+		   .name = "mt7628-esw",
+		   .of_match_table = mt7628_of_match,
+		    },
+	.probe = mt7628_probe,
+	.remove = mt7628_remove,
+	.shutdown = mt7628_shutdown,
+};
+
+module_platform_driver(mt7628_driver);
+
+MODULE_AUTHOR("Joris Vaisvila <joey@tinyisr.com>");
+MODULE_DESCRIPTION("Driver for Mediatek MT7628 embedded switch");
+MODULE_LICENSE("GPL");
-- 
2.53.0