[PATCH 0/5] net: dsa: microchip: Add support for KSZ8995XA/KS8995XA

[PATCH 0/5] net: dsa: microchip: Add support for KSZ8995XA/KS8995XA

[Linus Walleij]

This series breaks with the dated attempt to polish the old
KS8995 driver, and instead implement support for the KS8995XA
in the KSZ driver, and after that delete the old KS8995 driver.

The hardware clearly has the same ancestry, the KSZ8995XA is
just a rebrand of the much older Micrel KX8995XA switch.

The old drivers referce to "KS8995" was actually KS8995XA only,
it never supported the sibling devices KS8995E or KS8995MA.
This is reflected in this patch set.

Add new compatibles, add special code paths for the KSZ8995XA
and add a new tagger for the special front tag found in the
KSZ8995XA.

The patches were tested with the Actiontec MI424WR rev D (which
has the KS8995XA) and OpenWrt as userspace.

Signed-off-by: Linus Walleij <linusw@kernel.org>
---
Linus Walleij (5):
      net: dsa: microchip: Add fallback Micrel compatibles
      dt-bindings: net: dsa: microchip: Add KSZ8995XA
      net: dsa: tag_ks8995: Add the KS8995 tag handling
      net: dsa: microchip: Support Microchip KSZ8995XA / KS8995XA
      net: dsa: ks8995: Delete surplus driver

 .../devicetree/bindings/net/dsa/microchip,ksz.yaml |   1 +
 drivers/net/dsa/Kconfig                            |   8 -
 drivers/net/dsa/Makefile                           |   1 -
 drivers/net/dsa/ks8995.c                           | 857 ---------------------
 drivers/net/dsa/microchip/Kconfig                  |   1 +
 drivers/net/dsa/microchip/ksz8.c                   | 105 ++-
 drivers/net/dsa/microchip/ksz8_reg.h               |   2 +
 drivers/net/dsa/microchip/ksz_common.c             | 115 ++-
 drivers/net/dsa/microchip/ksz_common.h             |  11 +-
 drivers/net/dsa/microchip/ksz_spi.c                |  33 +-
 include/linux/platform_data/microchip-ksz.h        |   1 +
 include/net/dsa.h                                  |   2 +
 net/dsa/Kconfig                                    |   6 +
 net/dsa/Makefile                                   |   1 +
 net/dsa/tag_ks8995.c                               | 134 ++++
 15 files changed, 376 insertions(+), 902 deletions(-)
---
base-commit: 254f49634ee16a731174d2ae34bc50bd5f45e731
change-id: 20260509-ks8995-to-ksz8-15f3f9c8271f

Best regards,
--  
Linus Walleij <linusw@kernel.org>

[PATCH 1/5] net: dsa: microchip: Add fallback Micrel compatibles

[Linus Walleij]

Because of forking paths when Micrel was acquired by Microchip,
two devices also exist with the micrel,* prefix bindings.
Add these to the KSZ SPI driver so users can use the more capable
driver.

Signed-off-by: Linus Walleij <linusw@kernel.org>
---
 drivers/net/dsa/microchip/ksz_spi.c | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/drivers/net/dsa/microchip/ksz_spi.c b/drivers/net/dsa/microchip/ksz_spi.c
index d8001734b057..c38eda65aaf2 100644
--- a/drivers/net/dsa/microchip/ksz_spi.c
+++ b/drivers/net/dsa/microchip/ksz_spi.c
@@ -224,6 +224,21 @@ static void ksz_spi_shutdown(struct spi_device *spi)
 }
 
 static const struct of_device_id ksz_dt_ids[] = {
+	/*
+	 * Legacy Micrel bindings. In 2015 Microchip acquired
+	 * Micrel which is the originator of the KSZ series, and
+	 * devices branded for Micrel already existed, as well as
+	 * some device tree bindings. These two products are identical
+	 * to the same Microchip products.
+	 */
+	{
+		.compatible = "micrel,ksz8864",
+		.data = &ksz_switch_chips[KSZ8864]
+	},
+	{
+		.compatible = "micrel,ksz8795",
+		.data = &ksz_switch_chips[KSZ8795]
+	},
 	{
 		.compatible = "microchip,ksz8463",
 		.data = &ksz_switch_chips[KSZ8463]

-- 
2.54.0

[PATCH 2/5] dt-bindings: net: dsa: microchip: Add KSZ8995XA

[Linus Walleij]

The KSZ8995XA is just like the KSZ8795 and KSZ8864 a Micrel
product. It was renamed from KS8995XA to KSZ8995XA at some point,
but it has the same properties as the KS8995XA.

Be careful to use the full product name in this new compatible:
there is also KSZ8995MA and KSZ8995E which are not compatible
with the KS8995XA.

Signed-off-by: Linus Walleij <linusw@kernel.org>
---
 Documentation/devicetree/bindings/net/dsa/microchip,ksz.yaml | 1 +
 1 file changed, 1 insertion(+)

diff --git a/Documentation/devicetree/bindings/net/dsa/microchip,ksz.yaml b/Documentation/devicetree/bindings/net/dsa/microchip,ksz.yaml
index 8d4a3a9a33fc..4ed13870ed3a 100644
--- a/Documentation/devicetree/bindings/net/dsa/microchip,ksz.yaml
+++ b/Documentation/devicetree/bindings/net/dsa/microchip,ksz.yaml
@@ -23,6 +23,7 @@ properties:
       - microchip,ksz8864  # 4-port version of KSZ8895 family switch
       - microchip,ksz8873
       - microchip,ksz8895  # 5-port version of KSZ8895 family switch
+      - microchip,ksz8995xa
       - microchip,ksz9477
       - microchip,ksz9897
       - microchip,ksz9896

-- 
2.54.0

[PATCH 3/5] net: dsa: tag_ks8995: Add the KS8995 tag handling

[Linus Walleij]

The KS8995 100Mbit switch can do proper DSA per-port tagging
with the proper set-up. This adds the code to handle ingress
and egress KS8995 tags.

The tag is a modified 0x8100 ethertype tag where a bit in the
last nybble is set for each target port.

Signed-off-by: Linus Walleij <linusw@kernel.org>
---
 include/net/dsa.h    |   2 +
 net/dsa/Kconfig      |   6 +++
 net/dsa/Makefile     |   1 +
 net/dsa/tag_ks8995.c | 134 +++++++++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 143 insertions(+)

diff --git a/include/net/dsa.h b/include/net/dsa.h
index 8b6d34e8a6f0..4d110eb9754e 100644
--- a/include/net/dsa.h
+++ b/include/net/dsa.h
@@ -58,6 +58,7 @@ struct tc_action;
 #define DSA_TAG_PROTO_YT921X_VALUE		30
 #define DSA_TAG_PROTO_MXL_GSW1XX_VALUE		31
 #define DSA_TAG_PROTO_MXL862_VALUE		32
+#define DSA_TAG_PROTO_KS8995_VALUE		33
 
 enum dsa_tag_protocol {
 	DSA_TAG_PROTO_NONE		= DSA_TAG_PROTO_NONE_VALUE,
@@ -93,6 +94,7 @@ enum dsa_tag_protocol {
 	DSA_TAG_PROTO_YT921X		= DSA_TAG_PROTO_YT921X_VALUE,
 	DSA_TAG_PROTO_MXL_GSW1XX	= DSA_TAG_PROTO_MXL_GSW1XX_VALUE,
 	DSA_TAG_PROTO_MXL862		= DSA_TAG_PROTO_MXL862_VALUE,
+	DSA_TAG_PROTO_KS8995		= DSA_TAG_PROTO_KS8995_VALUE,
 };
 
 struct dsa_switch;
diff --git a/net/dsa/Kconfig b/net/dsa/Kconfig
index 5ed8c704636d..11fd72891759 100644
--- a/net/dsa/Kconfig
+++ b/net/dsa/Kconfig
@@ -119,6 +119,12 @@ config NET_DSA_TAG_MXL_GSW1XX
 	  Say Y or M if you want to enable support for tagging frames for
 	  MaxLinear GSW1xx switches.
 
+config NET_DSA_TAG_KS8995
+	tristate "Tag driver for Micrel KS8995 switch"
+	help
+	  Say Y if you want to enable support for tagging frames for the
+	  Micrel KS8995 switch.
+
 config NET_DSA_TAG_KSZ
 	tristate "Tag driver for Microchip 8795/937x/9477/9893 families of switches"
 	help
diff --git a/net/dsa/Makefile b/net/dsa/Makefile
index bf7247759a64..8ff313f1d329 100644
--- a/net/dsa/Makefile
+++ b/net/dsa/Makefile
@@ -25,6 +25,7 @@ obj-$(CONFIG_NET_DSA_TAG_BRCM_COMMON) += tag_brcm.o
 obj-$(CONFIG_NET_DSA_TAG_DSA_COMMON) += tag_dsa.o
 obj-$(CONFIG_NET_DSA_TAG_GSWIP) += tag_gswip.o
 obj-$(CONFIG_NET_DSA_TAG_HELLCREEK) += tag_hellcreek.o
+obj-$(CONFIG_NET_DSA_TAG_KS8995) += tag_ks8995.o
 obj-$(CONFIG_NET_DSA_TAG_KSZ) += tag_ksz.o
 obj-$(CONFIG_NET_DSA_TAG_LAN9303) += tag_lan9303.o
 obj-$(CONFIG_NET_DSA_TAG_MTK) += tag_mtk.o
diff --git a/net/dsa/tag_ks8995.c b/net/dsa/tag_ks8995.c
new file mode 100644
index 000000000000..6ae6789751d9
--- /dev/null
+++ b/net/dsa/tag_ks8995.c
@@ -0,0 +1,134 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2026 Linus Walleij <linusw@kernel.org>
+ */
+#include <linux/etherdevice.h>
+#include <linux/log2.h>
+#include <linux/list.h>
+#include <linux/slab.h>
+
+#include "tag.h"
+
+/* The KS8995 Special Tag Packet ID (STPID)
+ * pushes its tag in a modified VLAN (802.1Q) tag.
+ * -----------------------------------------------------------
+ * | MAC DA | MAC SA | 2 bytes tag | 2 bytes TCI | EtherType |
+ * -----------------------------------------------------------
+ * The tag is: 0x8100 |= BIT(port), ports 0,1,2,3
+ */
+
+#define KS8995_NAME "ks8995"
+
+#define KS8995M_STPID_STD	GENMASK(15, 4)
+#define KS8995M_STPID_PORTMASK	GENMASK(3, 0)
+#define KS8995M_STPID(portmask)	htons(ETH_P_8021Q | FIELD_PREP(KS8995M_STPID_PORTMASK, portmask))
+
+static struct sk_buff *ks8995_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+	struct vlan_ethhdr *hdr = vlan_eth_hdr(skb);
+	bool have_hwaccel_tag = false;
+	u16 tci = 0, portmask;
+
+	/* Prepare the special KS8995 tags */
+	portmask = dsa_xmit_port_mask(skb, dev);
+
+	if (skb_vlan_tag_present(skb) && skb->vlan_proto == htons(ETH_P_8021Q)) {
+		tci = skb_vlan_tag_get(skb);
+		__vlan_hwaccel_clear_tag(skb);
+		have_hwaccel_tag = true;
+	}
+
+	if (have_hwaccel_tag || hdr->h_vlan_proto != htons(ETH_P_8021Q)) {
+		skb = vlan_insert_tag(skb, KS8995M_STPID(portmask), tci);
+		if (!skb)
+			return NULL;
+		hdr = vlan_eth_hdr(skb);
+		netdev_dbg(dev, "%s: inserted VLAN TAG %04x TCI %04x\n",
+			   __func__, hdr->h_vlan_proto, hdr->h_vlan_TCI);
+	} else {
+		/* VLAN tag already exists in skb head, modify it in place */
+		hdr = vlan_eth_hdr(skb);
+		hdr->h_vlan_proto = KS8995M_STPID(portmask);
+		hdr->h_vlan_TCI = htons(tci);
+		netdev_dbg(dev, "%s: modified VLAN TAG %04x TCI %04x\n",
+			   __func__, hdr->h_vlan_proto, hdr->h_vlan_TCI);
+	}
+
+	return skb;
+}
+
+static struct sk_buff *ks8995_rcv(struct sk_buff *skb, struct net_device *dev)
+{
+	int portmask;
+	u16 etype;
+
+	/* We are expecting all received packets to have a mangled VLAN
+	 * TPID, so drop anything else. Because of the non-standard TPID,
+	 * don't even bother looking for a tag in the hwaccel area.
+	 *
+	 * We have to inspect the ethertype directly because skb->protocol
+	 * will contain garbage.
+	 */
+	etype = ntohs(*(u16 *)dsa_etype_header_pos_rx(skb));
+	if ((etype & KS8995M_STPID_STD) != ETH_P_8021Q) {
+		netdev_info(dev, "%s: dropped ethertype 0x%04x\n",
+			    __func__, etype);
+		return NULL;
+	}
+	netdev_dbg(dev, "%s: received ethertype %04x\n",
+		   __func__, etype);
+
+	/* Move the custom DSA+VLAN tag into the hwaccel area and strip
+	 * it from the skb head
+	 */
+	skb = skb_vlan_untag(skb);
+	if (!skb) {
+		netdev_err(dev, "%s: unable to untag protocol %04x vlan protocol  %04x\n",
+			   __func__, ntohs(skb->protocol), ntohs(skb->vlan_proto));
+		return NULL;
+	}
+
+	portmask = FIELD_GET(KS8995M_STPID_PORTMASK, etype);
+	netdev_dbg(dev, "%s: etype %04x portmask %04x (%d)\n",
+		   __func__, etype, portmask, ilog2(portmask));
+	skb->dev = dsa_conduit_find_user(dev, 0, ilog2(portmask));
+	if (!skb->dev)
+		return NULL;
+
+	/* Preserve the VLAN tag if it contains a non-zero VID which is not
+	 * identical to 0x001, or PCP, and restore its TPID to the standard
+	 * value.
+	 *
+	 * If this is just an ordinary inbound package the datasheet claims
+	 * it will "replace null VID with ingress port VID", which means
+	 * VID set to 1: 0x8101 0001 for port 0 or 0x8102 0001 for port 1.
+	 * So in the DSA driver we will set the default port VID to 0 so
+	 * we can properly detect non-VLAN frames.
+	 */
+	if (!skb->vlan_tci) {
+		netdev_dbg(dev, "%s: clear VLAN tag from frame\n", __func__);
+		__vlan_hwaccel_clear_tag(skb);
+	} else {
+		skb->vlan_proto = htons(ETH_P_8021Q);
+		netdev_dbg(dev, "%s: vlan_tci = 0x%04x VLAN frame\n",
+			   __func__, skb->vlan_tci);
+	}
+
+	dsa_default_offload_fwd_mark(skb);
+
+	return skb;
+}
+
+static const struct dsa_device_ops ks8995_netdev_ops = {
+	.name = KS8995_NAME,
+	.proto	= DSA_TAG_PROTO_KS8995,
+	.xmit = ks8995_xmit,
+	.rcv = ks8995_rcv,
+	.needed_headroom = VLAN_HLEN,
+};
+
+MODULE_DESCRIPTION("DSA tag driver for Micrel KS8995 family of switches");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_KS8995, KS8995_NAME);
+
+module_dsa_tag_driver(ks8995_netdev_ops);

-- 
2.54.0

[PATCH 4/5] net: dsa: microchip: Support Microchip KSZ8995XA / KS8995XA

[Linus Walleij]

This adds support for the Microchip KSZ8995XA also known as the
Micrel KS8995XA switch to the KSZ driver.

Notice: there are also KSZ8995E and KSZ8995MA. These are BOTH
different from the KSZ8995XA.

The helper macros are named ksz_is_ksz8995xa() to make it
possible to add E and MA support in the future.

Signed-off-by: Linus Walleij <linusw@kernel.org>
---
 drivers/net/dsa/Kconfig                     |   1 +
 drivers/net/dsa/microchip/Kconfig           |   1 +
 drivers/net/dsa/microchip/ksz8.c            | 105 +++++++++++++++++++------
 drivers/net/dsa/microchip/ksz8_reg.h        |   2 +
 drivers/net/dsa/microchip/ksz_common.c      | 115 ++++++++++++++++++++++++++--
 drivers/net/dsa/microchip/ksz_common.h      |  11 ++-
 drivers/net/dsa/microchip/ksz_spi.c         |  18 ++++-
 include/linux/platform_data/microchip-ksz.h |   1 +
 8 files changed, 218 insertions(+), 36 deletions(-)

diff --git a/drivers/net/dsa/Kconfig b/drivers/net/dsa/Kconfig
index 39fb8ead16b5..b91b9766ebc2 100644
--- a/drivers/net/dsa/Kconfig
+++ b/drivers/net/dsa/Kconfig
@@ -98,6 +98,7 @@ config NET_DSA_RZN1_A5PSW
 config NET_DSA_KS8995
 	tristate "Micrel KS8995 family 5-ports 10/100 Ethernet switches"
 	depends on SPI
+	depends on !NET_DSA_MICROCHIP_KSZ_SPI
 	select NET_DSA_TAG_NONE
 	help
 	  This driver supports the Micrel KS8995 family of 10/100 Mbit ethernet
diff --git a/drivers/net/dsa/microchip/Kconfig b/drivers/net/dsa/microchip/Kconfig
index c71d3fd5dfeb..75c9b2114afd 100644
--- a/drivers/net/dsa/microchip/Kconfig
+++ b/drivers/net/dsa/microchip/Kconfig
@@ -2,6 +2,7 @@
 menuconfig NET_DSA_MICROCHIP_KSZ_COMMON
 	tristate "Microchip KSZ8XXX/KSZ9XXX/LAN937X series switch support"
 	depends on NET_DSA
+	select NET_DSA_TAG_KS8995
 	select NET_DSA_TAG_KSZ
 	select NET_DSA_TAG_NONE
 	select NET_IEEE8021Q_HELPERS
diff --git a/drivers/net/dsa/microchip/ksz8.c b/drivers/net/dsa/microchip/ksz8.c
index c354abdafc1b..c58d87abdd83 100644
--- a/drivers/net/dsa/microchip/ksz8.c
+++ b/drivers/net/dsa/microchip/ksz8.c
@@ -3,6 +3,7 @@
  * Microchip KSZ8XXX series switch driver
  *
  * It supports the following switches:
+ * - KSZ8995XA (the oldest ancestor)
  * - KSZ8463
  * - KSZ8863, KSZ8873 aka KSZ88X3
  * - KSZ8895, KSZ8864 aka KSZ8895 family
@@ -135,7 +136,10 @@ int ksz8_pme_pwrite8(struct ksz_device *dev, int port, int offset, u8 data)
 
 int ksz8_reset_switch(struct ksz_device *dev)
 {
-	if (ksz_is_ksz88x3(dev)) {
+	if (ksz_is_ksz8995xa(dev)) {
+		/* KSZ8995XA lacks software reset */
+		return 0;
+	} else if (ksz_is_ksz88x3(dev)) {
 		/* reset switch */
 		ksz_cfg(dev, KSZ8863_REG_SW_RESET,
 			KSZ8863_GLOBAL_SOFTWARE_RESET | KSZ8863_PCS_RESET, true);
@@ -159,8 +163,14 @@ int ksz8_reset_switch(struct ksz_device *dev)
 static int ksz8863_change_mtu(struct ksz_device *dev, int frame_size)
 {
 	u8 ctrl2 = 0;
+	unsigned int legalsz;
+
+	if (ksz_is_ksz8995xa(dev))
+		legalsz = KSZ8995XA_LEGAL_PACKET_SIZE;
+	else
+		legalsz = KSZ8_LEGAL_PACKET_SIZE;
 
-	if (frame_size <= KSZ8_LEGAL_PACKET_SIZE)
+	if (frame_size <= legalsz)
 		ctrl2 |= KSZ8863_LEGAL_PACKET_ENABLE;
 	else if (frame_size > KSZ8863_NORMAL_PACKET_SIZE)
 		ctrl2 |= KSZ8863_HUGE_PACKET_ENABLE;
@@ -204,6 +214,7 @@ int ksz8_change_mtu(struct ksz_device *dev, int port, int mtu)
 	case KSZ88X3_CHIP_ID:
 	case KSZ8864_CHIP_ID:
 	case KSZ8895_CHIP_ID:
+	case KSZ8995XA_CHIP_ID:
 		return ksz8863_change_mtu(dev, frame_size);
 	}
 
@@ -838,6 +849,10 @@ static int ksz8_r_phy_ctrl(struct ksz_device *dev, int port, u16 *val)
 	if (reg_val & PORT_MDIX_STATUS)
 		*val |= KSZ886X_CTRL_MDIX_STAT;
 
+	/* KSZ8995XA has no fancy features in register 0xA */
+	if (ksz_is_ksz8995xa(dev))
+		return 0;
+
 	ret = ksz_pread8(dev, port, REG_PORT_LINK_MD_CTRL, &reg_val);
 	if (ret < 0)
 		return ret;
@@ -936,8 +951,10 @@ static int ksz8_r_phy_bmcr(struct ksz_device *dev, u16 port, u16 *val)
 	if (ctrl & PORT_FORCE_FULL_DUPLEX)
 		*val |= BMCR_FULLDPLX;
 
-	if (speed & PORT_HP_MDIX)
-		*val |= KSZ886X_BMCR_HP_MDIX;
+	if (!ksz_is_ksz8995xa(dev)) {
+		if (speed & PORT_HP_MDIX)
+			*val |= KSZ886X_BMCR_HP_MDIX;
+	}
 
 	if (restart & PORT_FORCE_MDIX)
 		*val |= KSZ886X_BMCR_FORCE_MDI;
@@ -1032,6 +1049,9 @@ int ksz8_r_phy(struct ksz_device *dev, u16 phy, u16 reg, u16 *val)
 			data |= LPA_LPACK;
 		break;
 	case PHY_REG_LINK_MD:
+		if (ksz_is_ksz8995xa(dev))
+			return -EOPNOTSUPP;
+
 		ret = ksz_pread8(dev, p, REG_PORT_LINK_MD_CTRL, &val1);
 		if (ret)
 			return ret;
@@ -1146,13 +1166,15 @@ static int ksz8_w_phy_bmcr(struct ksz_device *dev, u16 port, u16 val)
 	if (val & BMCR_RESET)
 		return 0;
 
-	speed = 0;
-	if (val & KSZ886X_BMCR_HP_MDIX)
-		speed |= PORT_HP_MDIX;
+	if (!ksz_is_ksz8995xa(dev)) {
+		speed = 0;
+		if (val & KSZ886X_BMCR_HP_MDIX)
+			speed |= PORT_HP_MDIX;
 
-	ret = ksz_prmw8(dev, port, regs[P_SPEED_STATUS], PORT_HP_MDIX, speed);
-	if (ret)
-		return ret;
+		ret = ksz_prmw8(dev, port, regs[P_SPEED_STATUS], PORT_HP_MDIX, speed);
+		if (ret)
+			return ret;
+	}
 
 	ctrl = 0;
 	if (ksz_is_ksz88x3(dev)) {
@@ -1262,11 +1284,17 @@ int ksz8_w_phy(struct ksz_device *dev, u16 phy, u16 reg, u16 val)
 		}
 		break;
 	case PHY_REG_LINK_MD:
+		if (ksz_is_ksz8995xa(dev))
+			return -EOPNOTSUPP;
+
 		if (val & PHY_START_CABLE_DIAG)
 			ksz_port_cfg(dev, p, REG_PORT_LINK_MD_CTRL, PORT_START_CABLE_DIAG, true);
 		break;
 
 	case PHY_REG_PHY_CTRL:
+		if (ksz_is_ksz8995xa(dev))
+			return -EOPNOTSUPP;
+
 		ret = ksz8_w_phy_ctrl(dev, p, val);
 		if (ret)
 			return ret;
@@ -1458,7 +1486,7 @@ int ksz8_fdb_del(struct ksz_device *dev, int port, const unsigned char *addr,
 int ksz8_port_vlan_filtering(struct ksz_device *dev, int port, bool flag,
 			     struct netlink_ext_ack *extack)
 {
-	if (ksz_is_ksz88x3(dev) || ksz_is_ksz8463(dev))
+	if (ksz_is_ksz88x3(dev) || ksz_is_ksz8463(dev) || ksz_is_ksz8995xa(dev))
 		return -ENOTSUPP;
 
 	/* Discard packets with VID not enabled on the switch */
@@ -1670,14 +1698,16 @@ void ksz8_port_setup(struct ksz_device *dev, int port, bool cpu_port)
 		offset = P1CR1;
 	ksz_port_cfg(dev, port, offset, PORT_BROADCAST_STORM, true);
 
-	ksz8_port_queue_split(dev, port, dev->info->num_tx_queues);
+	if (!ksz_is_ksz8995xa(dev)) {
+		ksz8_port_queue_split(dev, port, dev->info->num_tx_queues);
 
-	/* replace priority */
-	offset = P_802_1P_CTRL;
-	if (ksz_is_ksz8463(dev))
-		offset = P1CR2;
-	ksz_port_cfg(dev, port, offset,
-		     masks[PORT_802_1P_REMAPPING], false);
+		/* replace priority */
+		offset = P_802_1P_CTRL;
+		if (ksz_is_ksz8463(dev))
+			offset = P1CR2;
+		ksz_port_cfg(dev, port, offset,
+			     masks[PORT_802_1P_REMAPPING], false);
+	}
 
 	if (cpu_port)
 		member = dsa_user_ports(ds);
@@ -1686,6 +1716,19 @@ void ksz8_port_setup(struct ksz_device *dev, int port, bool cpu_port)
 
 	ksz8_cfg_port_member(dev, port, member);
 
+	if (ksz_is_ksz8995xa(dev)) {
+		/*
+		 * The KSZ8995XA has a special tag format in the front of the frame
+		 * that need to be inserted by the CPU and then removed by each
+		 * port. PORT_REMOVE_TAG simply means "remove tags coming from the
+		 * CPU port" it does not affect ingress packets.
+		 */
+		if (cpu_port)
+			ksz_port_cfg(dev, port, offset, PORT_INSERT_TAG, true);
+		else
+			ksz_port_cfg(dev, port, offset, PORT_REMOVE_TAG, true);
+	}
+
 	/* Disable all WoL options by default. Otherwise
 	 * ksz_switch_macaddr_get/put logic will not work properly.
 	 * CPU port 4 has no WoL functionality.
@@ -1722,7 +1765,9 @@ void ksz8_config_cpu_port(struct dsa_switch *ds)
 	masks = dev->info->masks;
 	regs = dev->info->regs;
 
-	ksz_cfg(dev, regs[S_TAIL_TAG_CTRL], masks[SW_TAIL_TAG_ENABLE], true);
+	/* KSZ8995XA uses a tag in the header instead of the tail */
+	if (!ksz_is_ksz8995xa(dev))
+		ksz_cfg(dev, regs[S_TAIL_TAG_CTRL], masks[SW_TAIL_TAG_ENABLE], true);
 
 	ksz8_port_setup(dev, dev->cpu_port, true);
 
@@ -1922,6 +1967,10 @@ int ksz8_enable_stp_addr(struct ksz_device *dev)
 {
 	struct alu_struct alu;
 
+	/* KSZ8995XA lacks STP */
+	if (ksz_is_ksz8995xa(dev))
+		return 0;
+
 	/* Setup STP address for STP operation. */
 	memset(&alu, 0, sizeof(alu));
 	ether_addr_copy(alu.mac, eth_stp_addr);
@@ -1937,6 +1986,7 @@ int ksz8_setup(struct dsa_switch *ds)
 	struct ksz_device *dev = ds->priv;
 	const u16 *regs = dev->info->regs;
 	int i, ret = 0;
+	u8 val;
 
 	ds->mtu_enforcement_ingress = true;
 
@@ -1962,9 +2012,10 @@ int ksz8_setup(struct dsa_switch *ds)
 	 * Make sure unicast VLAN boundary is set as default and
 	 * enable no excessive collision drop.
 	 */
-	ret = ksz_rmw8(dev, REG_SW_CTRL_2,
-		       UNICAST_VLAN_BOUNDARY | NO_EXC_COLLISION_DROP,
-		       UNICAST_VLAN_BOUNDARY | NO_EXC_COLLISION_DROP);
+	val = NO_EXC_COLLISION_DROP;
+	if (!ksz_is_ksz8995xa(dev))
+		val |= UNICAST_VLAN_BOUNDARY;
+	ret = ksz_rmw8(dev, REG_SW_CTRL_2, val, val);
 	if (ret)
 		return ret;
 
@@ -1972,11 +2023,15 @@ int ksz8_setup(struct dsa_switch *ds)
 
 	ksz_cfg(dev, S_MIRROR_CTRL, SW_MIRROR_RX_TX, false);
 
-	if (!ksz_is_ksz88x3(dev) && !ksz_is_ksz8463(dev))
+	if (ksz_is_ksz8995xa(dev))
+		ksz_cfg(dev, REG_SW_CTRL_9, SW_SPECIAL_TAG, true);
+	else if (!ksz_is_ksz88x3(dev) && !ksz_is_ksz8463(dev))
 		ksz_cfg(dev, REG_SW_CTRL_19, SW_INS_TAG_ENABLE, true);
 
-	for (i = 0; i < (dev->info->num_vlans / 4); i++)
-		ksz8_r_vlan_entries(dev, i);
+	if (!ksz_is_ksz8995xa(dev)) {
+		for (i = 0; i < (dev->info->num_vlans / 4); i++)
+			ksz8_r_vlan_entries(dev, i);
+	}
 
 	/* Make sure PME (WoL) is not enabled. If requested, it will
 	 * be enabled by ksz_wol_pre_shutdown(). Otherwise, some PMICs
diff --git a/drivers/net/dsa/microchip/ksz8_reg.h b/drivers/net/dsa/microchip/ksz8_reg.h
index 332408567b47..1be2fa161ac8 100644
--- a/drivers/net/dsa/microchip/ksz8_reg.h
+++ b/drivers/net/dsa/microchip/ksz8_reg.h
@@ -95,6 +95,8 @@
 #define SW_LED_LINK_ACT_DUPLEX		2
 #define SW_LED_LINK_DUPLEX		3
 
+#define SW_SPECIAL_TAG			BIT(0) /* KSZ8995XA only */
+
 #define REG_SW_CTRL_10			0x0C
 
 #define SW_PASS_PAUSE			BIT(0)
diff --git a/drivers/net/dsa/microchip/ksz_common.c b/drivers/net/dsa/microchip/ksz_common.c
index 144373e13bea..aa69b696e882 100644
--- a/drivers/net/dsa/microchip/ksz_common.c
+++ b/drivers/net/dsa/microchip/ksz_common.c
@@ -332,6 +332,29 @@ static const struct phylink_mac_ops ksz8_phylink_mac_ops = {
 	.mac_enable_tx_lpi = ksz_phylink_mac_enable_tx_lpi,
 };
 
+/*
+ * The KS(Z)8995XA has no indirect access, meaning no MIB counters,
+ * no FDB access, and no VLAN handling.
+ */
+static const struct ksz_dev_ops ksz8995xa_dev_ops = {
+	.setup = ksz8_setup,
+	.get_port_addr = ksz8_get_port_addr,
+	.cfg_port_member = ksz8_cfg_port_member,
+	.flush_dyn_mac_table = ksz8_flush_dyn_mac_table,
+	.port_setup = ksz8_port_setup,
+	.r_phy = ksz8_r_phy,
+	.w_phy = ksz8_w_phy,
+	.mirror_add = ksz8_port_mirror_add,
+	.mirror_del = ksz8_port_mirror_del,
+	.get_caps = ksz8_get_caps,
+	.config_cpu_port = ksz8_config_cpu_port,
+	.enable_stp_addr = ksz8_enable_stp_addr,
+	.reset = ksz8_reset_switch,
+	.init = ksz8_switch_init,
+	.exit = ksz8_switch_exit,
+	.change_mtu = ksz8_change_mtu,
+};
+
 static const struct ksz_dev_ops ksz8463_dev_ops = {
 	.setup = ksz8_setup,
 	.get_port_addr = ksz8463_get_port_addr,
@@ -798,6 +821,20 @@ static const u8 ksz8895_shifts[] = {
 	[DYNAMIC_MAC_SRC_PORT]		= 24,
 };
 
+static const u16 ksz8995xa_regs[] = {
+	[REG_SW_MAC_ADDR]		= 0x68,
+	[P_FORCE_CTRL]			= 0x0C,
+	[P_LINK_STATUS]			= 0x0E,
+	[P_LOCAL_CTRL]			= 0x0C,
+	[P_NEG_RESTART_CTRL]		= 0x0D,
+	[P_REMOTE_STATUS]		= 0x0E,
+	[P_SPEED_STATUS]		= 0x09,
+	[P_STP_CTRL]			= 0x02,
+	[S_START_CTRL]			= 0x01,
+	[S_BROADCAST_CTRL]		= 0x06,
+	[S_MULTICAST_CTRL]		= 0x04,
+};
+
 static const u16 ksz9477_regs[] = {
 	[REG_SW_MAC_ADDR]		= 0x0302,
 	[P_STP_CTRL]			= 0x0B04,
@@ -1721,6 +1758,20 @@ const struct ksz_chip_data ksz_switch_chips[] = {
 		.internal_phy = {true, true, true, true, false},
 	},
 
+	[KSZ8995XA] = {
+		.chip_id = KSZ8995XA_CHIP_ID, /* Also known as KS8995XA */
+		.dev_name = "KSZ8995XA",
+		.cpu_ports = 0x10,	/* can be configured as cpu port */
+		.port_cnt = 5,		/* total cpu and user ports */
+		.num_tx_queues = 4,
+		.num_ipms = 4,
+		.ops = &ksz8995xa_dev_ops,
+		.phylink_mac_ops = &ksz88x3_phylink_mac_ops,
+		.regs = ksz8995xa_regs,
+		.supports_mii = {true, true, true, true, true},
+		.internal_phy = {true, true, true, true, false},
+	},
+
 	[KSZ9477] = {
 		.chip_id = KSZ9477_CHIP_ID,
 		.dev_name = "KSZ9477",
@@ -3191,6 +3242,10 @@ void ksz_init_mib_timer(struct ksz_device *dev)
 {
 	int i;
 
+	/* KSZ8995XA lacks MiB features */
+	if (ksz_is_ksz8995xa(dev))
+		return;
+
 	INIT_DELAYED_WORK(&dev->mib_read, ksz_mib_read_work);
 
 	for (i = 0; i < dev->info->port_cnt; i++) {
@@ -3534,7 +3589,9 @@ static enum dsa_tag_protocol ksz_get_tag_protocol(struct dsa_switch *ds,
 	struct ksz_device *dev = ds->priv;
 	enum dsa_tag_protocol proto = DSA_TAG_PROTO_NONE;
 
-	if (ksz_is_ksz87xx(dev) || ksz_is_8895_family(dev))
+	if (ksz_is_ksz8995xa(dev))
+		proto = DSA_TAG_PROTO_KS8995;
+	else if (ksz_is_ksz87xx(dev) || ksz_is_8895_family(dev))
 		proto = DSA_TAG_PROTO_KSZ8795;
 
 	if (dev->chip_id == KSZ88X3_CHIP_ID ||
@@ -3564,6 +3621,7 @@ static int ksz_connect_tag_protocol(struct dsa_switch *ds,
 	struct ksz_tagger_data *tagger_data;
 
 	switch (proto) {
+	case DSA_TAG_PROTO_KS8995:
 	case DSA_TAG_PROTO_KSZ8795:
 		return 0;
 	case DSA_TAG_PROTO_KSZ9893:
@@ -3655,6 +3713,7 @@ static int ksz_max_mtu(struct dsa_switch *ds, int port)
 	case KSZ88X3_CHIP_ID:
 	case KSZ8864_CHIP_ID:
 	case KSZ8895_CHIP_ID:
+	case KSZ8995XA_CHIP_ID:
 		return KSZ8863_HUGE_PACKET_SIZE - VLAN_ETH_HLEN - ETH_FCS_LEN;
 	case KSZ8563_CHIP_ID:
 	case KSZ8567_CHIP_ID:
@@ -4031,11 +4090,15 @@ static int ksz_switch_detect(struct ksz_device *dev)
 			return -ENODEV;
 		break;
 	case KSZ8895_FAMILY_ID:
-		if (id2 == KSZ8895_CHIP_ID_95 ||
-		    id2 == KSZ8895_CHIP_ID_95R)
+		if (id2 == KSZ8895_CHIP_ID_95XA) {
+			dev->chip_id = KSZ8995XA_CHIP_ID;
+			break;
+		} else if (id2 == KSZ8895_CHIP_ID_95 ||
+			   id2 == KSZ8895_CHIP_ID_95R) {
 			dev->chip_id = KSZ8895_CHIP_ID;
-		else
+		} else {
 			return -ENODEV;
+		}
 		ret = ksz_read8(dev, REG_KSZ8864_CHIP_ID, &id4);
 		if (ret)
 			return ret;
@@ -5034,6 +5097,36 @@ static const struct dsa_switch_ops ksz_switch_ops = {
 	.port_set_apptrust	= ksz_port_set_apptrust,
 };
 
+/*
+ * Restricted operations for KSZ8995XA, so many things are not supported
+ * by this old switch that we need diet DSA operations.
+ */
+static const struct dsa_switch_ops ksz8995xa_switch_ops = {
+	.get_tag_protocol	= ksz_get_tag_protocol,
+	.connect_tag_protocol   = ksz_connect_tag_protocol,
+	.get_phy_flags		= ksz_get_phy_flags,
+	.setup			= ksz_setup,
+	.teardown		= ksz_teardown,
+	.phy_read		= ksz_phy_read16,
+	.phy_write		= ksz_phy_write16,
+	.phylink_get_caps	= ksz_phylink_get_caps,
+	.port_setup		= ksz_port_setup,
+	.port_bridge_join	= ksz_port_bridge_join,
+	.port_bridge_leave	= ksz_port_bridge_leave,
+	.port_set_mac_address	= ksz_port_set_mac_address,
+	.port_stp_state_set	= ksz_port_stp_state_set,
+	.port_teardown		= ksz_port_teardown,
+	.port_pre_bridge_flags	= ksz_port_pre_bridge_flags,
+	.port_bridge_flags	= ksz_port_bridge_flags,
+	.port_fast_age		= ksz_port_fast_age,
+	.port_mirror_add	= ksz_port_mirror_add,
+	.port_mirror_del	= ksz_port_mirror_del,
+	.port_change_mtu	= ksz_change_mtu,
+	.port_max_mtu		= ksz_max_mtu,
+	.port_get_apptrust	= ksz_port_get_apptrust,
+	.port_set_apptrust	= ksz_port_set_apptrust,
+};
+
 struct ksz_device *ksz_switch_alloc(struct device *base, void *priv)
 {
 	struct dsa_switch *ds;
@@ -5450,6 +5543,10 @@ int ksz_switch_register(struct ksz_device *dev)
 	if (ret)
 		return ret;
 
+	/* Override ops with something simpler for this legacy chip */
+	if (ksz_is_ksz8995xa(dev))
+		dev->ds->ops = &ksz8995xa_switch_ops;
+
 	dev->dev_ops = dev->info->ops;
 
 	ret = dev->dev_ops->init(dev);
@@ -5534,11 +5631,13 @@ int ksz_switch_register(struct ksz_device *dev)
 		return ret;
 	}
 
-	/* Read MIB counters every 30 seconds to avoid overflow. */
-	dev->mib_read_interval = msecs_to_jiffies(5000);
+	if (!ksz_is_ksz8995xa(dev)) {
+		/* Read MIB counters every 30 seconds to avoid overflow. */
+		dev->mib_read_interval = msecs_to_jiffies(5000);
 
-	/* Start the MIB timer. */
-	schedule_delayed_work(&dev->mib_read, 0);
+		/* Start the MIB timer. */
+		schedule_delayed_work(&dev->mib_read, 0);
+	}
 
 	return ret;
 }
diff --git a/drivers/net/dsa/microchip/ksz_common.h b/drivers/net/dsa/microchip/ksz_common.h
index 18f13ee9c7b6..dee29ca9eda6 100644
--- a/drivers/net/dsa/microchip/ksz_common.h
+++ b/drivers/net/dsa/microchip/ksz_common.h
@@ -234,6 +234,7 @@ enum ksz_model {
 	KSZ88X3,
 	KSZ8864,
 	KSZ8895,
+	KSZ8995XA,
 	KSZ9477,
 	KSZ9896,
 	KSZ9897,
@@ -720,7 +721,13 @@ static inline bool ksz_is_ksz88x3(struct ksz_device *dev)
 static inline bool ksz_is_8895_family(struct ksz_device *dev)
 {
 	return dev->chip_id == KSZ8895_CHIP_ID ||
-	       dev->chip_id == KSZ8864_CHIP_ID;
+	       dev->chip_id == KSZ8864_CHIP_ID ||
+	       dev->chip_id == KSZ8995XA_CHIP_ID;
+}
+
+static inline bool ksz_is_ksz8995xa(struct ksz_device *dev)
+{
+	return dev->chip_id == KSZ8995XA_CHIP_ID;
 }
 
 static inline bool is_ksz8(struct ksz_device *dev)
@@ -791,6 +798,7 @@ static inline bool ksz_is_sgmii_port(struct ksz_device *dev, int port)
 #define KSZ87_CHIP_ID_94		0x6
 #define KSZ87_CHIP_ID_95		0x9
 #define KSZ88_CHIP_ID_63		0x3
+#define KSZ8895_CHIP_ID_95XA		0x0
 #define KSZ8895_CHIP_ID_95		0x4
 #define KSZ8895_CHIP_ID_95R		0x6
 
@@ -854,6 +862,7 @@ static inline bool ksz_is_sgmii_port(struct ksz_device *dev, int port)
 #define KSZ8863_HUGE_PACKET_SIZE	1916
 #define KSZ8863_NORMAL_PACKET_SIZE	1536
 #define KSZ8_LEGAL_PACKET_SIZE		1518
+#define KSZ8995XA_LEGAL_PACKET_SIZE	1522
 #define KSZ9477_MAX_FRAME_SIZE		9000
 
 #define KSZ8873_REG_GLOBAL_CTRL_12	0x0e
diff --git a/drivers/net/dsa/microchip/ksz_spi.c b/drivers/net/dsa/microchip/ksz_spi.c
index c38eda65aaf2..ceadcdef6039 100644
--- a/drivers/net/dsa/microchip/ksz_spi.c
+++ b/drivers/net/dsa/microchip/ksz_spi.c
@@ -161,7 +161,8 @@ static int ksz_spi_probe(struct spi_device *spi)
 		 chip->chip_id == KSZ8794_CHIP_ID ||
 		 chip->chip_id == KSZ8765_CHIP_ID)
 		regmap_config = ksz8795_regmap_config;
-	else if (chip->chip_id == KSZ8895_CHIP_ID ||
+	else if (chip->chip_id == KSZ8995XA_CHIP_ID ||
+		 chip->chip_id == KSZ8895_CHIP_ID ||
 		 chip->chip_id == KSZ8864_CHIP_ID)
 		regmap_config = ksz8863_regmap_config;
 	else
@@ -185,7 +186,10 @@ static int ksz_spi_probe(struct spi_device *spi)
 		dev->pdata = spi->dev.platform_data;
 
 	/* setup spi */
-	spi->mode = SPI_MODE_3;
+	if (chip->chip_id == KSZ8995XA_CHIP_ID)
+		spi->mode = SPI_MODE_0;
+	else
+		spi->mode = SPI_MODE_3;
 	ret = spi_setup(spi);
 	if (ret)
 		return ret;
@@ -239,6 +243,10 @@ static const struct of_device_id ksz_dt_ids[] = {
 		.compatible = "micrel,ksz8795",
 		.data = &ksz_switch_chips[KSZ8795]
 	},
+	{
+		.compatible = "micrel,ks8995",
+		.data = &ksz_switch_chips[KSZ8995XA]
+	},
 	{
 		.compatible = "microchip,ksz8463",
 		.data = &ksz_switch_chips[KSZ8463]
@@ -271,6 +279,10 @@ static const struct of_device_id ksz_dt_ids[] = {
 		.compatible = "microchip,ksz8895",
 		.data = &ksz_switch_chips[KSZ8895]
 	},
+	{
+		.compatible = "microchip,ksz8995xa",
+		.data = &ksz_switch_chips[KSZ8995XA]
+	},
 	{
 		.compatible = "microchip,ksz9477",
 		.data = &ksz_switch_chips[KSZ9477]
@@ -332,6 +344,7 @@ static const struct of_device_id ksz_dt_ids[] = {
 MODULE_DEVICE_TABLE(of, ksz_dt_ids);
 
 static const struct spi_device_id ksz_spi_ids[] = {
+	{ "ks8995" },
 	{ "ksz8463" },
 	{ "ksz8765" },
 	{ "ksz8794" },
@@ -340,6 +353,7 @@ static const struct spi_device_id ksz_spi_ids[] = {
 	{ "ksz8864" },
 	{ "ksz8873" },
 	{ "ksz8895" },
+	{ "ksz8995" },
 	{ "ksz9477" },
 	{ "ksz9896" },
 	{ "ksz9897" },
diff --git a/include/linux/platform_data/microchip-ksz.h b/include/linux/platform_data/microchip-ksz.h
index 028781ad4059..d8eddd21c3c7 100644
--- a/include/linux/platform_data/microchip-ksz.h
+++ b/include/linux/platform_data/microchip-ksz.h
@@ -31,6 +31,7 @@ enum ksz_chip_id {
 	KSZ88X3_CHIP_ID = 0x8830,
 	KSZ8864_CHIP_ID = 0x8864,
 	KSZ8895_CHIP_ID = 0x8895,
+	KSZ8995XA_CHIP_ID = 0x8995,
 	KSZ9477_CHIP_ID = 0x00947700,
 	KSZ9896_CHIP_ID = 0x00989600,
 	KSZ9897_CHIP_ID = 0x00989700,

-- 
2.54.0

[PATCH 5/5] net: dsa: ks8995: Delete surplus driver

[Linus Walleij]

The Microchip ksz driver now handles all switches that the
old driver was handling, but better.

Delete the old driver.

Signed-off-by: Linus Walleij <linusw@kernel.org>
---
 drivers/net/dsa/Kconfig  |   9 -
 drivers/net/dsa/Makefile |   1 -
 drivers/net/dsa/ks8995.c | 857 -----------------------------------------------
 3 files changed, 867 deletions(-)

diff --git a/drivers/net/dsa/Kconfig b/drivers/net/dsa/Kconfig
index b91b9766ebc2..e6315573bea4 100644
--- a/drivers/net/dsa/Kconfig
+++ b/drivers/net/dsa/Kconfig
@@ -95,15 +95,6 @@ config NET_DSA_RZN1_A5PSW
 	  This driver supports the A5PSW switch, which is embedded in Renesas
 	  RZ/N1 SoC.
 
-config NET_DSA_KS8995
-	tristate "Micrel KS8995 family 5-ports 10/100 Ethernet switches"
-	depends on SPI
-	depends on !NET_DSA_MICROCHIP_KSZ_SPI
-	select NET_DSA_TAG_NONE
-	help
-	  This driver supports the Micrel KS8995 family of 10/100 Mbit ethernet
-	  switches, managed over SPI.
-
 config NET_DSA_SMSC_LAN9303
 	tristate
 	select NET_DSA_TAG_LAN9303
diff --git a/drivers/net/dsa/Makefile b/drivers/net/dsa/Makefile
index f5a463b87ec2..bbbadf2e41a2 100644
--- a/drivers/net/dsa/Makefile
+++ b/drivers/net/dsa/Makefile
@@ -2,7 +2,6 @@
 obj-$(CONFIG_NET_DSA_BCM_SF2)	+= bcm-sf2.o
 bcm-sf2-objs			:= bcm_sf2.o bcm_sf2_cfp.o
 obj-$(CONFIG_NET_DSA_LOOP)	+= dsa_loop.o
-obj-$(CONFIG_NET_DSA_KS8995) 	+= ks8995.o
 obj-$(CONFIG_NET_DSA_MT7530)	+= mt7530.o
 obj-$(CONFIG_NET_DSA_MT7530_MDIO) += mt7530-mdio.o
 obj-$(CONFIG_NET_DSA_MT7530_MMIO) += mt7530-mmio.o
diff --git a/drivers/net/dsa/ks8995.c b/drivers/net/dsa/ks8995.c
deleted file mode 100644
index 77d8b842693c..000000000000
--- a/drivers/net/dsa/ks8995.c
+++ /dev/null
@@ -1,857 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * SPI driver for Micrel/Kendin KS8995M and KSZ8864RMN ethernet switches
- *
- * Copyright (C) 2008 Gabor Juhos <juhosg at openwrt.org>
- * Copyright (C) 2025 Linus Walleij <linus.walleij@linaro.org>
- *
- * This file was based on: drivers/spi/at25.c
- *     Copyright (C) 2006 David Brownell
- */
-
-#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
-
-#include <linux/bits.h>
-#include <linux/if_bridge.h>
-#include <linux/if_vlan.h>
-#include <linux/types.h>
-#include <linux/kernel.h>
-#include <linux/module.h>
-#include <linux/delay.h>
-#include <linux/device.h>
-#include <linux/gpio/consumer.h>
-#include <linux/of.h>
-#include <linux/spi/spi.h>
-#include <net/dsa.h>
-
-#define DRV_VERSION		"0.1.1"
-#define DRV_DESC		"Micrel KS8995 Ethernet switch SPI driver"
-
-/* ------------------------------------------------------------------------ */
-
-#define KS8995_REG_ID0		0x00    /* Chip ID0 */
-#define KS8995_REG_ID1		0x01    /* Chip ID1 */
-
-#define KS8995_REG_GC0		0x02    /* Global Control 0 */
-
-#define KS8995_GC0_P5_PHY	BIT(3)	/* Port 5 PHY enabled */
-
-#define KS8995_REG_GC1		0x03    /* Global Control 1 */
-#define KS8995_REG_GC2		0x04    /* Global Control 2 */
-
-#define KS8995_GC2_HUGE		BIT(2)	/* Huge packet support */
-#define KS8995_GC2_LEGAL	BIT(1)	/* Legal size override */
-
-#define KS8995_REG_GC3		0x05    /* Global Control 3 */
-#define KS8995_REG_GC4		0x06    /* Global Control 4 */
-
-#define KS8995_GC4_10BT		BIT(4)	/* Force switch to 10Mbit */
-#define KS8995_GC4_MII_FLOW	BIT(5)	/* MII full-duplex flow control enable */
-#define KS8995_GC4_MII_HD	BIT(6)	/* MII half-duplex mode enable */
-
-#define KS8995_REG_GC5		0x07    /* Global Control 5 */
-#define KS8995_REG_GC6		0x08    /* Global Control 6 */
-#define KS8995_REG_GC7		0x09    /* Global Control 7 */
-#define KS8995_REG_GC8		0x0a    /* Global Control 8 */
-#define KS8995_REG_GC9		0x0b    /* Global Control 9 */
-
-#define KS8995_GC9_SPECIAL	BIT(0)	/* Special tagging mode (DSA) */
-
-/* In DSA the ports 1-4 are numbered 0-3 and the CPU port is port 4 */
-#define KS8995_REG_PC(p, r)	(0x10 + (0x10 * (p)) + (r)) /* Port Control */
-#define KS8995_REG_PS(p, r)	(0x1e + (0x10 * (p)) + (r)) /* Port Status */
-
-#define KS8995_REG_PC0		0x00    /* Port Control 0 */
-#define KS8995_REG_PC1		0x01    /* Port Control 1 */
-#define KS8995_REG_PC2		0x02    /* Port Control 2 */
-#define KS8995_REG_PC3		0x03    /* Port Control 3 */
-#define KS8995_REG_PC4		0x04    /* Port Control 4 */
-#define KS8995_REG_PC5		0x05    /* Port Control 5 */
-#define KS8995_REG_PC6		0x06    /* Port Control 6 */
-#define KS8995_REG_PC7		0x07    /* Port Control 7 */
-#define KS8995_REG_PC8		0x08    /* Port Control 8 */
-#define KS8995_REG_PC9		0x09    /* Port Control 9 */
-#define KS8995_REG_PC10		0x0a    /* Port Control 10 */
-#define KS8995_REG_PC11		0x0b    /* Port Control 11 */
-#define KS8995_REG_PC12		0x0c    /* Port Control 12 */
-#define KS8995_REG_PC13		0x0d    /* Port Control 13 */
-
-#define KS8995_PC0_TAG_INS	BIT(2)	/* Enable tag insertion on port */
-#define KS8995_PC0_TAG_REM	BIT(1)	/* Enable tag removal on port */
-#define KS8995_PC0_PRIO_EN	BIT(0)	/* Enable priority handling */
-
-#define KS8995_PC2_TXEN		BIT(2)	/* Enable TX on port */
-#define KS8995_PC2_RXEN		BIT(1)	/* Enable RX on port */
-#define KS8995_PC2_LEARN_DIS	BIT(0)	/* Disable learning on port */
-
-#define KS8995_PC13_TXDIS	BIT(6)	/* Disable transmitter */
-#define KS8995_PC13_PWDN	BIT(3)	/* Power down */
-
-#define KS8995_REG_TPC0		0x60    /* TOS Priority Control 0 */
-#define KS8995_REG_TPC1		0x61    /* TOS Priority Control 1 */
-#define KS8995_REG_TPC2		0x62    /* TOS Priority Control 2 */
-#define KS8995_REG_TPC3		0x63    /* TOS Priority Control 3 */
-#define KS8995_REG_TPC4		0x64    /* TOS Priority Control 4 */
-#define KS8995_REG_TPC5		0x65    /* TOS Priority Control 5 */
-#define KS8995_REG_TPC6		0x66    /* TOS Priority Control 6 */
-#define KS8995_REG_TPC7		0x67    /* TOS Priority Control 7 */
-
-#define KS8995_REG_MAC0		0x68    /* MAC address 0 */
-#define KS8995_REG_MAC1		0x69    /* MAC address 1 */
-#define KS8995_REG_MAC2		0x6a    /* MAC address 2 */
-#define KS8995_REG_MAC3		0x6b    /* MAC address 3 */
-#define KS8995_REG_MAC4		0x6c    /* MAC address 4 */
-#define KS8995_REG_MAC5		0x6d    /* MAC address 5 */
-
-#define KS8995_REG_IAC0		0x6e    /* Indirect Access Control 0 */
-#define KS8995_REG_IAC1		0x6f    /* Indirect Access Control 0 */
-#define KS8995_REG_IAD7		0x70    /* Indirect Access Data 7 */
-#define KS8995_REG_IAD6		0x71    /* Indirect Access Data 6 */
-#define KS8995_REG_IAD5		0x72    /* Indirect Access Data 5 */
-#define KS8995_REG_IAD4		0x73    /* Indirect Access Data 4 */
-#define KS8995_REG_IAD3		0x74    /* Indirect Access Data 3 */
-#define KS8995_REG_IAD2		0x75    /* Indirect Access Data 2 */
-#define KS8995_REG_IAD1		0x76    /* Indirect Access Data 1 */
-#define KS8995_REG_IAD0		0x77    /* Indirect Access Data 0 */
-
-#define KSZ8864_REG_ID1		0xfe	/* Chip ID in bit 7 */
-
-#define KS8995_REGS_SIZE	0x80
-#define KSZ8864_REGS_SIZE	0x100
-#define KSZ8795_REGS_SIZE	0x100
-
-#define ID1_CHIPID_M		0xf
-#define ID1_CHIPID_S		4
-#define ID1_REVISION_M		0x7
-#define ID1_REVISION_S		1
-#define ID1_START_SW		1	/* start the switch */
-
-#define FAMILY_KS8995		0x95
-#define FAMILY_KSZ8795		0x87
-#define CHIPID_M		0
-#define KS8995_CHIP_ID		0x00
-#define KSZ8864_CHIP_ID		0x01
-#define KSZ8795_CHIP_ID		0x09
-
-#define KS8995_CMD_WRITE	0x02U
-#define KS8995_CMD_READ		0x03U
-
-#define KS8995_CPU_PORT		4
-#define KS8995_NUM_PORTS	5 /* 5 ports including the CPU port */
-#define KS8995_RESET_DELAY	10 /* usec */
-
-enum ks8995_chip_variant {
-	ks8995,
-	ksz8864,
-	ksz8795,
-	max_variant
-};
-
-struct ks8995_chip_params {
-	char *name;
-	int family_id;
-	int chip_id;
-	int regs_size;
-	int addr_width;
-	int addr_shift;
-};
-
-static const struct ks8995_chip_params ks8995_chip[] = {
-	[ks8995] = {
-		.name = "KS8995MA",
-		.family_id = FAMILY_KS8995,
-		.chip_id = KS8995_CHIP_ID,
-		.regs_size = KS8995_REGS_SIZE,
-		.addr_width = 8,
-		.addr_shift = 0,
-	},
-	[ksz8864] = {
-		.name = "KSZ8864RMN",
-		.family_id = FAMILY_KS8995,
-		.chip_id = KSZ8864_CHIP_ID,
-		.regs_size = KSZ8864_REGS_SIZE,
-		.addr_width = 8,
-		.addr_shift = 0,
-	},
-	[ksz8795] = {
-		.name = "KSZ8795CLX",
-		.family_id = FAMILY_KSZ8795,
-		.chip_id = KSZ8795_CHIP_ID,
-		.regs_size = KSZ8795_REGS_SIZE,
-		.addr_width = 12,
-		.addr_shift = 1,
-	},
-};
-
-struct ks8995_switch {
-	struct spi_device	*spi;
-	struct device		*dev;
-	struct dsa_switch	*ds;
-	struct mutex		lock;
-	struct gpio_desc	*reset_gpio;
-	struct bin_attribute	regs_attr;
-	const struct ks8995_chip_params	*chip;
-	int			revision_id;
-	unsigned int max_mtu[KS8995_NUM_PORTS];
-};
-
-static const struct spi_device_id ks8995_id[] = {
-	{"ks8995", ks8995},
-	{"ksz8864", ksz8864},
-	{"ksz8795", ksz8795},
-	{ }
-};
-MODULE_DEVICE_TABLE(spi, ks8995_id);
-
-static const struct of_device_id ks8995_spi_of_match[] = {
-	{ .compatible = "micrel,ks8995" },
-	{ .compatible = "micrel,ksz8864" },
-	{ .compatible = "micrel,ksz8795" },
-	{ },
-};
-MODULE_DEVICE_TABLE(of, ks8995_spi_of_match);
-
-static inline u8 get_chip_id(u8 val)
-{
-	return (val >> ID1_CHIPID_S) & ID1_CHIPID_M;
-}
-
-static inline u8 get_chip_rev(u8 val)
-{
-	return (val >> ID1_REVISION_S) & ID1_REVISION_M;
-}
-
-/* create_spi_cmd - create a chip specific SPI command header
- * @ks: pointer to switch instance
- * @cmd: SPI command for switch
- * @address: register address for command
- *
- * Different chip families use different bit pattern to address the switches
- * registers:
- *
- * KS8995: 8bit command + 8bit address
- * KSZ8795: 3bit command + 12bit address + 1bit TR (?)
- */
-static inline __be16 create_spi_cmd(struct ks8995_switch *ks, int cmd,
-				    unsigned address)
-{
-	u16 result = cmd;
-
-	/* make room for address (incl. address shift) */
-	result <<= ks->chip->addr_width + ks->chip->addr_shift;
-	/* add address */
-	result |= address << ks->chip->addr_shift;
-	/* SPI protocol needs big endian */
-	return cpu_to_be16(result);
-}
-/* ------------------------------------------------------------------------ */
-static int ks8995_read(struct ks8995_switch *ks, char *buf,
-		 unsigned offset, size_t count)
-{
-	__be16 cmd;
-	struct spi_transfer t[2];
-	struct spi_message m;
-	int err;
-
-	cmd = create_spi_cmd(ks, KS8995_CMD_READ, offset);
-	spi_message_init(&m);
-
-	memset(&t, 0, sizeof(t));
-
-	t[0].tx_buf = &cmd;
-	t[0].len = sizeof(cmd);
-	spi_message_add_tail(&t[0], &m);
-
-	t[1].rx_buf = buf;
-	t[1].len = count;
-	spi_message_add_tail(&t[1], &m);
-
-	mutex_lock(&ks->lock);
-	err = spi_sync(ks->spi, &m);
-	mutex_unlock(&ks->lock);
-
-	return err ? err : count;
-}
-
-static int ks8995_write(struct ks8995_switch *ks, char *buf,
-		 unsigned offset, size_t count)
-{
-	__be16 cmd;
-	struct spi_transfer t[2];
-	struct spi_message m;
-	int err;
-
-	cmd = create_spi_cmd(ks, KS8995_CMD_WRITE, offset);
-	spi_message_init(&m);
-
-	memset(&t, 0, sizeof(t));
-
-	t[0].tx_buf = &cmd;
-	t[0].len = sizeof(cmd);
-	spi_message_add_tail(&t[0], &m);
-
-	t[1].tx_buf = buf;
-	t[1].len = count;
-	spi_message_add_tail(&t[1], &m);
-
-	mutex_lock(&ks->lock);
-	err = spi_sync(ks->spi, &m);
-	mutex_unlock(&ks->lock);
-
-	return err ? err : count;
-}
-
-static inline int ks8995_read_reg(struct ks8995_switch *ks, u8 addr, u8 *buf)
-{
-	return ks8995_read(ks, buf, addr, 1) != 1;
-}
-
-static inline int ks8995_write_reg(struct ks8995_switch *ks, u8 addr, u8 val)
-{
-	char buf = val;
-
-	return ks8995_write(ks, &buf, addr, 1) != 1;
-}
-
-/* ------------------------------------------------------------------------ */
-
-static int ks8995_stop(struct ks8995_switch *ks)
-{
-	return ks8995_write_reg(ks, KS8995_REG_ID1, 0);
-}
-
-static int ks8995_start(struct ks8995_switch *ks)
-{
-	return ks8995_write_reg(ks, KS8995_REG_ID1, 1);
-}
-
-static int ks8995_reset(struct ks8995_switch *ks)
-{
-	int err;
-
-	err = ks8995_stop(ks);
-	if (err)
-		return err;
-
-	udelay(KS8995_RESET_DELAY);
-
-	return ks8995_start(ks);
-}
-
-/* ks8995_get_revision - get chip revision
- * @ks: pointer to switch instance
- *
- * Verify chip family and id and get chip revision.
- */
-static int ks8995_get_revision(struct ks8995_switch *ks)
-{
-	int err;
-	u8 id0, id1, ksz8864_id;
-
-	/* read family id */
-	err = ks8995_read_reg(ks, KS8995_REG_ID0, &id0);
-	if (err) {
-		err = -EIO;
-		goto err_out;
-	}
-
-	/* verify family id */
-	if (id0 != ks->chip->family_id) {
-		dev_err(&ks->spi->dev, "chip family id mismatch: expected 0x%02x but 0x%02x read\n",
-			ks->chip->family_id, id0);
-		err = -ENODEV;
-		goto err_out;
-	}
-
-	switch (ks->chip->family_id) {
-	case FAMILY_KS8995:
-		/* try reading chip id at CHIP ID1 */
-		err = ks8995_read_reg(ks, KS8995_REG_ID1, &id1);
-		if (err) {
-			err = -EIO;
-			goto err_out;
-		}
-
-		/* verify chip id */
-		if ((get_chip_id(id1) == CHIPID_M) &&
-		    (get_chip_id(id1) == ks->chip->chip_id)) {
-			/* KS8995MA */
-			ks->revision_id = get_chip_rev(id1);
-		} else if (get_chip_id(id1) != CHIPID_M) {
-			/* KSZ8864RMN */
-			err = ks8995_read_reg(ks, KS8995_REG_ID1, &ksz8864_id);
-			if (err) {
-				err = -EIO;
-				goto err_out;
-			}
-
-			if ((ksz8864_id & 0x80) &&
-			    (ks->chip->chip_id == KSZ8864_CHIP_ID)) {
-				ks->revision_id = get_chip_rev(id1);
-			}
-
-		} else {
-			dev_err(&ks->spi->dev, "unsupported chip id for KS8995 family: 0x%02x\n",
-				id1);
-			err = -ENODEV;
-		}
-		break;
-	case FAMILY_KSZ8795:
-		/* try reading chip id at CHIP ID1 */
-		err = ks8995_read_reg(ks, KS8995_REG_ID1, &id1);
-		if (err) {
-			err = -EIO;
-			goto err_out;
-		}
-
-		if (get_chip_id(id1) == ks->chip->chip_id) {
-			ks->revision_id = get_chip_rev(id1);
-		} else {
-			dev_err(&ks->spi->dev, "unsupported chip id for KSZ8795 family: 0x%02x\n",
-				id1);
-			err = -ENODEV;
-		}
-		break;
-	default:
-		dev_err(&ks->spi->dev, "unsupported family id: 0x%02x\n", id0);
-		err = -ENODEV;
-		break;
-	}
-err_out:
-	return err;
-}
-
-static int ks8995_check_config(struct ks8995_switch *ks)
-{
-	int ret;
-	u8 val;
-
-	ret = ks8995_read_reg(ks, KS8995_REG_GC0, &val);
-	if (ret) {
-		dev_err(ks->dev, "failed to read KS8995_REG_GC0\n");
-		return ret;
-	}
-
-	dev_dbg(ks->dev, "port 5 PHY %senabled\n",
-		(val & KS8995_GC0_P5_PHY) ? "" : "not ");
-
-	val |= KS8995_GC0_P5_PHY;
-	ret = ks8995_write_reg(ks, KS8995_REG_GC0, val);
-	if (ret)
-		dev_err(ks->dev, "failed to set KS8995_REG_GC0\n");
-
-	dev_dbg(ks->dev, "set KS8995_REG_GC0 to 0x%02x\n", val);
-
-	return 0;
-}
-
-static void
-ks8995_mac_config(struct phylink_config *config, unsigned int mode,
-		  const struct phylink_link_state *state)
-{
-}
-
-static void
-ks8995_mac_link_up(struct phylink_config *config, struct phy_device *phydev,
-		   unsigned int mode, phy_interface_t interface,
-		   int speed, int duplex, bool tx_pause, bool rx_pause)
-{
-	struct dsa_port *dp = dsa_phylink_to_port(config);
-	struct ks8995_switch *ks = dp->ds->priv;
-	int port = dp->index;
-	int ret;
-	u8 val;
-
-	/* Allow forcing the mode on the fixed CPU port, no autonegotiation.
-	 * We assume autonegotiation works on the PHY-facing ports.
-	 */
-	if (port != KS8995_CPU_PORT)
-		return;
-
-	dev_dbg(ks->dev, "MAC link up on CPU port (%d)\n", port);
-
-	ret = ks8995_read_reg(ks, KS8995_REG_GC4, &val);
-	if (ret) {
-		dev_err(ks->dev, "failed to read KS8995_REG_GC4\n");
-		return;
-	}
-
-	/* Conjure port config */
-	switch (speed) {
-	case SPEED_10:
-		dev_dbg(ks->dev, "set switch MII to 100Mbit mode\n");
-		val |= KS8995_GC4_10BT;
-		break;
-	case SPEED_100:
-	default:
-		dev_dbg(ks->dev, "set switch MII to 100Mbit mode\n");
-		val &= ~KS8995_GC4_10BT;
-		break;
-	}
-
-	if (duplex == DUPLEX_HALF) {
-		dev_dbg(ks->dev, "set switch MII to half duplex\n");
-		val |= KS8995_GC4_MII_HD;
-	} else {
-		dev_dbg(ks->dev, "set switch MII to full duplex\n");
-		val &= ~KS8995_GC4_MII_HD;
-	}
-
-	dev_dbg(ks->dev, "set KS8995_REG_GC4 to %02x\n", val);
-
-	/* Enable the CPU port */
-	ret = ks8995_write_reg(ks, KS8995_REG_GC4, val);
-	if (ret)
-		dev_err(ks->dev, "failed to set KS8995_REG_GC4\n");
-}
-
-static void
-ks8995_mac_link_down(struct phylink_config *config, unsigned int mode,
-		     phy_interface_t interface)
-{
-	struct dsa_port *dp = dsa_phylink_to_port(config);
-	struct ks8995_switch *ks = dp->ds->priv;
-	int port = dp->index;
-
-	if (port != KS8995_CPU_PORT)
-		return;
-
-	dev_dbg(ks->dev, "MAC link down on CPU port (%d)\n", port);
-
-	/* Disable the CPU port */
-}
-
-static const struct phylink_mac_ops ks8995_phylink_mac_ops = {
-	.mac_config = ks8995_mac_config,
-	.mac_link_up = ks8995_mac_link_up,
-	.mac_link_down = ks8995_mac_link_down,
-};
-
-static enum
-dsa_tag_protocol ks8995_get_tag_protocol(struct dsa_switch *ds,
-					 int port,
-					 enum dsa_tag_protocol mp)
-{
-	/* This switch actually uses the 6 byte KS8995 protocol */
-	return DSA_TAG_PROTO_NONE;
-}
-
-static int ks8995_setup(struct dsa_switch *ds)
-{
-	return 0;
-}
-
-static int ks8995_port_enable(struct dsa_switch *ds, int port,
-			      struct phy_device *phy)
-{
-	struct ks8995_switch *ks = ds->priv;
-
-	dev_dbg(ks->dev, "enable port %d\n", port);
-
-	return 0;
-}
-
-static void ks8995_port_disable(struct dsa_switch *ds, int port)
-{
-	struct ks8995_switch *ks = ds->priv;
-
-	dev_dbg(ks->dev, "disable port %d\n", port);
-}
-
-static int ks8995_port_pre_bridge_flags(struct dsa_switch *ds, int port,
-					struct switchdev_brport_flags flags,
-					struct netlink_ext_ack *extack)
-{
-	/* We support enabling/disabling learning */
-	if (flags.mask & ~(BR_LEARNING))
-		return -EINVAL;
-
-	return 0;
-}
-
-static int ks8995_port_bridge_flags(struct dsa_switch *ds, int port,
-				    struct switchdev_brport_flags flags,
-				    struct netlink_ext_ack *extack)
-{
-	struct ks8995_switch *ks = ds->priv;
-	int ret;
-	u8 val;
-
-	if (flags.mask & BR_LEARNING) {
-		ret = ks8995_read_reg(ks, KS8995_REG_PC(port, KS8995_REG_PC2), &val);
-		if (ret) {
-			dev_err(ks->dev, "failed to read KS8995_REG_PC2 on port %d\n", port);
-			return ret;
-		}
-
-		if (flags.val & BR_LEARNING)
-			val &= ~KS8995_PC2_LEARN_DIS;
-		else
-			val |= KS8995_PC2_LEARN_DIS;
-
-		ret = ks8995_write_reg(ks, KS8995_REG_PC(port, KS8995_REG_PC2), val);
-		if (ret) {
-			dev_err(ks->dev, "failed to write KS8995_REG_PC2 on port %d\n", port);
-			return ret;
-		}
-	}
-
-	return 0;
-}
-
-static void ks8995_port_stp_state_set(struct dsa_switch *ds, int port, u8 state)
-{
-	struct ks8995_switch *ks = ds->priv;
-	int ret;
-	u8 val;
-
-	ret = ks8995_read_reg(ks, KS8995_REG_PC(port, KS8995_REG_PC2), &val);
-	if (ret) {
-		dev_err(ks->dev, "failed to read KS8995_REG_PC2 on port %d\n", port);
-		return;
-	}
-
-	/* Set the bits for the different STP states in accordance with
-	 * the datasheet, pages 36-37 "Spanning tree support".
-	 */
-	switch (state) {
-	case BR_STATE_DISABLED:
-	case BR_STATE_BLOCKING:
-	case BR_STATE_LISTENING:
-		val &= ~KS8995_PC2_TXEN;
-		val &= ~KS8995_PC2_RXEN;
-		val |= KS8995_PC2_LEARN_DIS;
-		break;
-	case BR_STATE_LEARNING:
-		val &= ~KS8995_PC2_TXEN;
-		val &= ~KS8995_PC2_RXEN;
-		val &= ~KS8995_PC2_LEARN_DIS;
-		break;
-	case BR_STATE_FORWARDING:
-		val |= KS8995_PC2_TXEN;
-		val |= KS8995_PC2_RXEN;
-		val &= ~KS8995_PC2_LEARN_DIS;
-		break;
-	default:
-		dev_err(ks->dev, "unknown bridge state requested\n");
-		return;
-	}
-
-	ret = ks8995_write_reg(ks, KS8995_REG_PC(port, KS8995_REG_PC2), val);
-	if (ret) {
-		dev_err(ks->dev, "failed to write KS8995_REG_PC2 on port %d\n", port);
-		return;
-	}
-
-	dev_dbg(ks->dev, "set KS8995_REG_PC2 for port %d to %02x\n", port, val);
-}
-
-static void ks8995_phylink_get_caps(struct dsa_switch *dsa, int port,
-				    struct phylink_config *config)
-{
-	unsigned long *interfaces = config->supported_interfaces;
-
-	if (port == KS8995_CPU_PORT)
-		__set_bit(PHY_INTERFACE_MODE_MII, interfaces);
-
-	if (port <= 3) {
-		/* Internal PHYs */
-		__set_bit(PHY_INTERFACE_MODE_INTERNAL, interfaces);
-		/* phylib default */
-		__set_bit(PHY_INTERFACE_MODE_MII, interfaces);
-	}
-
-	config->mac_capabilities = MAC_SYM_PAUSE | MAC_10 | MAC_100;
-}
-
-/* Huge packet support up to 1916 byte packages "inclusive"
- * which means that tags are included. If the bit is not set
- * it is 1536 bytes "inclusive". We present the length without
- * tags or ethernet headers. The setting affects all ports.
- */
-static int ks8995_change_mtu(struct dsa_switch *ds, int port, int new_mtu)
-{
-	struct ks8995_switch *ks = ds->priv;
-	unsigned int max_mtu;
-	int ret;
-	u8 val;
-	int i;
-
-	ks->max_mtu[port] = new_mtu;
-
-	/* Roof out the MTU for the entire switch to the greatest
-	 * common denominator: the biggest set for any one port will
-	 * be the biggest MTU for the switch.
-	 */
-	max_mtu = ETH_DATA_LEN;
-	for (i = 0; i < KS8995_NUM_PORTS; i++) {
-		if (ks->max_mtu[i] > max_mtu)
-			max_mtu = ks->max_mtu[i];
-	}
-
-	/* Translate to layer 2 size.
-	 * Add ethernet and (possible) VLAN headers, and checksum to the size.
-	 * For ETH_DATA_LEN (1500 bytes) this will add up to 1522 bytes.
-	 */
-	max_mtu += VLAN_ETH_HLEN;
-	max_mtu += ETH_FCS_LEN;
-
-	ret = ks8995_read_reg(ks, KS8995_REG_GC2, &val);
-	if (ret) {
-		dev_err(ks->dev, "failed to read KS8995_REG_GC2\n");
-		return ret;
-	}
-
-	if (max_mtu <= 1522) {
-		val &= ~KS8995_GC2_HUGE;
-		val &= ~KS8995_GC2_LEGAL;
-	} else if (max_mtu > 1522 && max_mtu <= 1536) {
-		/* This accepts packets up to 1536 bytes */
-		val &= ~KS8995_GC2_HUGE;
-		val |= KS8995_GC2_LEGAL;
-	} else {
-		/* This accepts packets up to 1916 bytes */
-		val |= KS8995_GC2_HUGE;
-		val |= KS8995_GC2_LEGAL;
-	}
-
-	dev_dbg(ks->dev, "new max MTU %d bytes (inclusive)\n", max_mtu);
-
-	ret = ks8995_write_reg(ks, KS8995_REG_GC2, val);
-	if (ret)
-		dev_err(ks->dev, "failed to set KS8995_REG_GC2\n");
-
-	return ret;
-}
-
-static int ks8995_get_max_mtu(struct dsa_switch *ds, int port)
-{
-	return 1916 - ETH_HLEN - ETH_FCS_LEN;
-}
-
-static const struct dsa_switch_ops ks8995_ds_ops = {
-	.get_tag_protocol = ks8995_get_tag_protocol,
-	.setup = ks8995_setup,
-	.port_pre_bridge_flags = ks8995_port_pre_bridge_flags,
-	.port_bridge_flags = ks8995_port_bridge_flags,
-	.port_enable = ks8995_port_enable,
-	.port_disable = ks8995_port_disable,
-	.port_stp_state_set = ks8995_port_stp_state_set,
-	.port_change_mtu = ks8995_change_mtu,
-	.port_max_mtu = ks8995_get_max_mtu,
-	.phylink_get_caps = ks8995_phylink_get_caps,
-};
-
-/* ------------------------------------------------------------------------ */
-static int ks8995_probe(struct spi_device *spi)
-{
-	struct ks8995_switch *ks;
-	int err;
-	int variant = spi_get_device_id(spi)->driver_data;
-
-	if (variant >= max_variant) {
-		dev_err(&spi->dev, "bad chip variant %d\n", variant);
-		return -ENODEV;
-	}
-
-	ks = devm_kzalloc(&spi->dev, sizeof(*ks), GFP_KERNEL);
-	if (!ks)
-		return -ENOMEM;
-
-	mutex_init(&ks->lock);
-	ks->spi = spi;
-	ks->dev = &spi->dev;
-	ks->chip = &ks8995_chip[variant];
-
-	ks->reset_gpio = devm_gpiod_get_optional(&spi->dev, "reset",
-						 GPIOD_OUT_HIGH);
-	err = PTR_ERR_OR_ZERO(ks->reset_gpio);
-	if (err) {
-		dev_err(&spi->dev,
-			"failed to get reset gpio: %d\n", err);
-		return err;
-	}
-
-	err = gpiod_set_consumer_name(ks->reset_gpio, "switch-reset");
-	if (err)
-		return err;
-
-	if (ks->reset_gpio) {
-		/*
-		 * If a reset line was obtained, wait for 100us after
-		 * de-asserting RESET before accessing any registers, see
-		 * the KS8995MA datasheet, page 44.
-		 */
-		gpiod_set_value_cansleep(ks->reset_gpio, 0);
-		udelay(100);
-	}
-
-	spi_set_drvdata(spi, ks);
-
-	spi->mode = SPI_MODE_0;
-	spi->bits_per_word = 8;
-	err = spi_setup(spi);
-	if (err) {
-		dev_err(&spi->dev, "spi_setup failed, err=%d\n", err);
-		return err;
-	}
-
-	err = ks8995_get_revision(ks);
-	if (err)
-		return err;
-
-	err = ks8995_reset(ks);
-	if (err)
-		return err;
-
-	dev_info(&spi->dev, "%s device found, Chip ID:%x, Revision:%x\n",
-		 ks->chip->name, ks->chip->chip_id, ks->revision_id);
-
-	err = ks8995_check_config(ks);
-	if (err)
-		return err;
-
-	ks->ds = devm_kzalloc(&spi->dev, sizeof(*ks->ds), GFP_KERNEL);
-	if (!ks->ds)
-		return -ENOMEM;
-
-	ks->ds->dev = &spi->dev;
-	ks->ds->num_ports = KS8995_NUM_PORTS;
-	ks->ds->ops = &ks8995_ds_ops;
-	ks->ds->phylink_mac_ops = &ks8995_phylink_mac_ops;
-	ks->ds->priv = ks;
-
-	err = dsa_register_switch(ks->ds);
-	if (err)
-		return dev_err_probe(&spi->dev, err,
-				     "unable to register DSA switch\n");
-
-	return 0;
-}
-
-static void ks8995_remove(struct spi_device *spi)
-{
-	struct ks8995_switch *ks = spi_get_drvdata(spi);
-
-	dsa_unregister_switch(ks->ds);
-	/* assert reset */
-	gpiod_set_value_cansleep(ks->reset_gpio, 1);
-}
-
-/* ------------------------------------------------------------------------ */
-static struct spi_driver ks8995_driver = {
-	.driver = {
-		.name	    = "spi-ks8995",
-		.of_match_table = ks8995_spi_of_match,
-	},
-	.probe	  = ks8995_probe,
-	.remove	  = ks8995_remove,
-	.id_table = ks8995_id,
-};
-
-module_spi_driver(ks8995_driver);
-
-MODULE_DESCRIPTION(DRV_DESC);
-MODULE_VERSION(DRV_VERSION);
-MODULE_AUTHOR("Gabor Juhos <juhosg at openwrt.org>");
-MODULE_LICENSE("GPL v2");

-- 
2.54.0

Re: [PATCH 0/5] net: dsa: microchip: Add support for KSZ8995XA/KS8995XA

[Linus Walleij]

On Sat, May 16, 2026 at 1:16 AM Linus Walleij <linusw@kernel.org> wrote:

> This series breaks with the dated attempt to polish the old
> KS8995 driver, and instead implement support for the KS8995XA
> in the KSZ driver, and after that delete the old KS8995 driver.

Obviously the patch series should have "net-next" in the
patch brackets. I am just expecting review comments and
AI buzz so I will need to spin many versions anyway.

Linus Walleij

Re: [PATCH 2/5] dt-bindings: net: dsa: microchip: Add KSZ8995XA

[Krzysztof Kozlowski]

On 16/05/2026 01:16, Linus Walleij wrote:
> The KSZ8995XA is just like the KSZ8795 and KSZ8864 a Micrel
> product. It was renamed from KS8995XA to KSZ8995XA at some point,
> but it has the same properties as the KS8995XA.

This is a bit unfortunate sentence, because it strongly suggests devices
are compatible, but you do not express any compatibility. Driver looks
handling them in incompatible way, so it is odd to see "it is just like".

Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>

Best regards,
Krzysztof

Re: [PATCH 2/5] dt-bindings: net: dsa: microchip: Add KSZ8995XA

[Linus Walleij]

On Sun, May 17, 2026 at 10:42 AM Krzysztof Kozlowski <krzk@kernel.org> wrote:
> On 16/05/2026 01:16, Linus Walleij wrote:
> > The KSZ8995XA is just like the KSZ8795 and KSZ8864 a Micrel
> > product. It was renamed from KS8995XA to KSZ8995XA at some point,
> > but it has the same properties as the KS8995XA.
>
> This is a bit unfortunate sentence, because it strongly suggests devices
> are compatible, but you do not express any compatibility. Driver looks
> handling them in incompatible way, so it is odd to see "it is just like".

Hm, they are compatible. The driver should handle KS8995XA and KSZ8995XA
the same way, the only thing that is funky in the driver is that since there
is (unfortunately) an old "micrel,ks8995" (no suffixes) binding, which is
actually the KS8995XA, we need to treat that as the XA binding as well.

I should probably patch it deprecated.

> Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>

Thanks!

Yours,
Linus Walleij

Re: [PATCH 0/5] net: dsa: microchip: Add support for KSZ8995XA/KS8995XA

[Jakub Kicinski]

On Sat, 16 May 2026 17:04:38 +0200 Linus Walleij wrote:
> > This series breaks with the dated attempt to polish the old
> > KS8995 driver, and instead implement support for the KS8995XA
> > in the KSZ driver, and after that delete the old KS8995 driver.  
> 
> Obviously the patch series should have "net-next" in the
> patch brackets. I am just expecting review comments and
> AI buzz so I will need to spin many versions anyway.

Looks like there some AI buzz in sashiko, but also - it doesn't 
apply on net-next.