[PATCH RFC V2 0/4] add Vertexcom MSE102x support

[PATCH RFC V2 0/4] add Vertexcom MSE102x support

[Stefan Wahren]

This patch series adds support for the Vertexcom MSE102x Homeplug GreenPHY
chips [1]. They can be connected either via RGMII, RMII or SPI to a host CPU.
These patches handles only the last one, with an Ethernet over SPI protocol
driver.

The code has been tested only on Raspberry Pi boards, but should work
on other platforms.

Any comments about the code are welcome.

Changes in V2:
- improve lock handling for RX & TX path
- add new patch to introduce IF_PORT_HOMEPLUG as suggested by Andrew Lunn
- address all the comments by Jakub Kicinski, Andrew Lunn, Kernel test robot

[1] - http://www.vertexcom.com/p_homeplug_plc_en.html

Stefan Wahren (4):
  dt-bindings: add vendor Vertexcom
  dt-bindings: net: add Vertexcom MSE102x support
  net: introduce media selection IF_PORT_HOMEPLUG
  net: vertexcom: Add MSE102x SPI support

 .../devicetree/bindings/net/vertexcom-mse102x.yaml |  71 ++
 .../devicetree/bindings/vendor-prefixes.yaml       |   2 +
 drivers/net/ethernet/Kconfig                       |   1 +
 drivers/net/ethernet/Makefile                      |   1 +
 drivers/net/ethernet/vertexcom/Kconfig             |  25 +
 drivers/net/ethernet/vertexcom/Makefile            |   6 +
 drivers/net/ethernet/vertexcom/mse102x.c           | 770 +++++++++++++++++++++
 include/uapi/linux/netdevice.h                     |   3 +-
 8 files changed, 878 insertions(+), 1 deletion(-)
 create mode 100644 Documentation/devicetree/bindings/net/vertexcom-mse102x.yaml
 create mode 100644 drivers/net/ethernet/vertexcom/Kconfig
 create mode 100644 drivers/net/ethernet/vertexcom/Makefile
 create mode 100644 drivers/net/ethernet/vertexcom/mse102x.c

-- 
2.7.4

[PATCH RFC V2 1/4] dt-bindings: add vendor Vertexcom

[Stefan Wahren]

Add vendor prefix for Vertexcom Technologies, Inc [1].

[1] - http://www.vertexcom.com/

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Acked-by: Rob Herring <robh@kernel.org>
---
 Documentation/devicetree/bindings/vendor-prefixes.yaml | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/Documentation/devicetree/bindings/vendor-prefixes.yaml b/Documentation/devicetree/bindings/vendor-prefixes.yaml
index 84cd16f..2ffea43 100644
--- a/Documentation/devicetree/bindings/vendor-prefixes.yaml
+++ b/Documentation/devicetree/bindings/vendor-prefixes.yaml
@@ -1276,6 +1276,8 @@ patternProperties:
     description: Variscite Ltd.
   "^vdl,.*":
     description: Van der Laan b.v.
+  "^vertexcom,.*":
+    description: Vertexcom Technologies, Inc.
   "^via,.*":
     description: VIA Technologies, Inc.
   "^videostrong,.*":
-- 
2.7.4

[PATCH RFC V2 2/4] dt-bindings: net: add Vertexcom MSE102x support

[Stefan Wahren]

Add devicetree binding for the Vertexcom MSE102x Homeplug GreenPHY chip
as SPI device.

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Reviewed-by: Rob Herring <robh@kernel.org>
---
 .../devicetree/bindings/net/vertexcom-mse102x.yaml | 71 ++++++++++++++++++++++
 1 file changed, 71 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/net/vertexcom-mse102x.yaml

diff --git a/Documentation/devicetree/bindings/net/vertexcom-mse102x.yaml b/Documentation/devicetree/bindings/net/vertexcom-mse102x.yaml
new file mode 100644
index 0000000..8156a9a
--- /dev/null
+++ b/Documentation/devicetree/bindings/net/vertexcom-mse102x.yaml
@@ -0,0 +1,71 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: "http://devicetree.org/schemas/net/vertexcom-mse102x.yaml#"
+$schema: "http://devicetree.org/meta-schemas/core.yaml#"
+
+title: The Vertexcom MSE102x (SPI) Device Tree Bindings
+
+maintainers:
+  - Stefan Wahren <stefan.wahren@in-tech.com>
+
+description:
+  Vertexcom's MSE102x are a family of HomePlug GreenPHY chips.
+  They can be connected either via RGMII, RMII or SPI to a host CPU.
+
+  In order to use a MSE102x chip as SPI device, it must be defined as
+  a child of an SPI master device in the device tree.
+
+  More information can be found at
+    http://www.vertexcom.com/doc/MSE1022%20Product%20Brief.pdf
+
+allOf:
+  - $ref: ethernet-controller.yaml#
+
+properties:
+  compatible:
+    enum:
+      - vertexcom,mse1021
+      - vertexcom,mse1022
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+  spi-cpha: true
+
+  spi-cpol: true
+
+  spi-max-frequency:
+    minimum: 6000000
+    maximum: 7142857
+
+required:
+  - compatible
+  - reg
+  - interrupts
+  - spi-cpha
+  - spi-cpol
+  - spi-max-frequency
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/interrupt-controller/irq.h>
+    spi0 {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        ethernet@0 {
+            compatible = "vertexcom,mse1021";
+            reg = <0>;
+            interrupt-parent = <&gpio>;
+            interrupts = <23 IRQ_TYPE_EDGE_RISING>;
+            spi-cpha;
+            spi-cpol;
+            spi-max-frequency = <7142857>;
+        };
+    };
-- 
2.7.4

[PATCH RFC V2 3/4] net: introduce media selection IF_PORT_HOMEPLUG

[Stefan Wahren]

Introduce a new media selection dedicated for HomePlug powerline
communication. This allows us to use the proper if_port setting in
HomePlug drivers.

Suggested-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
---
 include/uapi/linux/netdevice.h | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/include/uapi/linux/netdevice.h b/include/uapi/linux/netdevice.h
index f3770c5..0f1f536 100644
--- a/include/uapi/linux/netdevice.h
+++ b/include/uapi/linux/netdevice.h
@@ -53,7 +53,8 @@ enum {
         IF_PORT_AUI,
         IF_PORT_100BASET,
         IF_PORT_100BASETX,
-        IF_PORT_100BASEFX
+        IF_PORT_100BASEFX,
+        IF_PORT_HOMEPLUG
 };
 
 /* hardware address assignment types */
-- 
2.7.4

[PATCH RFC V2 4/4] net: vertexcom: Add MSE102x SPI support

[Stefan Wahren]

This implements an SPI protocol driver for Vertexcom MSE102x
Homeplug GreenPHY chip.

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
---
 drivers/net/ethernet/Kconfig             |   1 +
 drivers/net/ethernet/Makefile            |   1 +
 drivers/net/ethernet/vertexcom/Kconfig   |  25 +
 drivers/net/ethernet/vertexcom/Makefile  |   6 +
 drivers/net/ethernet/vertexcom/mse102x.c | 770 +++++++++++++++++++++++++++++++
 5 files changed, 803 insertions(+)
 create mode 100644 drivers/net/ethernet/vertexcom/Kconfig
 create mode 100644 drivers/net/ethernet/vertexcom/Makefile
 create mode 100644 drivers/net/ethernet/vertexcom/mse102x.c

diff --git a/drivers/net/ethernet/Kconfig b/drivers/net/ethernet/Kconfig
index 027cbac..db3ec47 100644
--- a/drivers/net/ethernet/Kconfig
+++ b/drivers/net/ethernet/Kconfig
@@ -183,6 +183,7 @@ source "drivers/net/ethernet/tehuti/Kconfig"
 source "drivers/net/ethernet/ti/Kconfig"
 source "drivers/net/ethernet/toshiba/Kconfig"
 source "drivers/net/ethernet/tundra/Kconfig"
+source "drivers/net/ethernet/vertexcom/Kconfig"
 source "drivers/net/ethernet/via/Kconfig"
 source "drivers/net/ethernet/wiznet/Kconfig"
 source "drivers/net/ethernet/xilinx/Kconfig"
diff --git a/drivers/net/ethernet/Makefile b/drivers/net/ethernet/Makefile
index 33d30b6..8a87c10 100644
--- a/drivers/net/ethernet/Makefile
+++ b/drivers/net/ethernet/Makefile
@@ -93,6 +93,7 @@ obj-$(CONFIG_NET_VENDOR_TEHUTI) += tehuti/
 obj-$(CONFIG_NET_VENDOR_TI) += ti/
 obj-$(CONFIG_NET_VENDOR_TOSHIBA) += toshiba/
 obj-$(CONFIG_NET_VENDOR_TUNDRA) += tundra/
+obj-$(CONFIG_NET_VENDOR_VERTEXCOM) += vertexcom/
 obj-$(CONFIG_NET_VENDOR_VIA) += via/
 obj-$(CONFIG_NET_VENDOR_WIZNET) += wiznet/
 obj-$(CONFIG_NET_VENDOR_XILINX) += xilinx/
diff --git a/drivers/net/ethernet/vertexcom/Kconfig b/drivers/net/ethernet/vertexcom/Kconfig
new file mode 100644
index 0000000..4184a63
--- /dev/null
+++ b/drivers/net/ethernet/vertexcom/Kconfig
@@ -0,0 +1,25 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# Vertexcom network device configuration
+#
+
+config NET_VENDOR_VERTEXCOM
+	bool "Vertexcom devices"
+	default y
+	help
+	  If you have a network (Ethernet) card belonging to this class, say Y.
+
+	  Note that the answer to this question doesn't directly affect the
+	  kernel: saying N will just cause the configurator to skip all
+	  the questions about Vertexcom cards. If you say Y, you will be asked
+	  for your specific card in the following questions.
+
+if NET_VENDOR_VERTEXCOM
+
+config MSE102X
+	tristate "Vertexcom MSE102x SPI"
+	depends on SPI
+	help
+	  SPI driver for Vertexcom MSE102x SPI attached network chip.
+
+endif # NET_VENDOR_VERTEXCOM
diff --git a/drivers/net/ethernet/vertexcom/Makefile b/drivers/net/ethernet/vertexcom/Makefile
new file mode 100644
index 0000000..f8b12e3
--- /dev/null
+++ b/drivers/net/ethernet/vertexcom/Makefile
@@ -0,0 +1,6 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Makefile for the Vertexcom network device drivers.
+#
+
+obj-$(CONFIG_MSE102X) += mse102x.o
diff --git a/drivers/net/ethernet/vertexcom/mse102x.c b/drivers/net/ethernet/vertexcom/mse102x.c
new file mode 100644
index 0000000..242fe85
--- /dev/null
+++ b/drivers/net/ethernet/vertexcom/mse102x.c
@@ -0,0 +1,770 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright (C) 2021 in-tech smart charging GmbH
+ *
+ * driver is based on micrel/ks8851_spi.c
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/ethtool.h>
+#include <linux/cache.h>
+#include <linux/debugfs.h>
+#include <linux/seq_file.h>
+
+#include <linux/spi/spi.h>
+#include <linux/of_net.h>
+
+#define MSG_DEFAULT	(NETIF_MSG_DRV | NETIF_MSG_PROBE | NETIF_MSG_LINK | \
+			 NETIF_MSG_TIMER)
+
+#define DRV_NAME	"mse102x"
+
+#define DET_CMD		0x0001
+#define DET_SOF		0x0002
+#define DET_DFT		0x55AA
+
+#define CMD_SHIFT	12
+#define CMD_RTS		(0x1 << CMD_SHIFT)
+#define CMD_CTR		(0x2 << CMD_SHIFT)
+
+#define CMD_MASK	GENMASK(15, CMD_SHIFT)
+#define LEN_MASK	GENMASK(CMD_SHIFT - 1, 0)
+
+#define DET_CMD_LEN	4
+#define DET_SOF_LEN	2
+#define DET_DFT_LEN	2
+
+#define MIN_FREQ_HZ	6000000
+#define MAX_FREQ_HZ	7142857
+
+struct mse102x_stats {
+	u64 xfer_err;
+	u64 invalid_cmd;
+	u64 invalid_ctr;
+	u64 invalid_dft;
+	u64 invalid_len;
+	u64 invalid_rts;
+	u64 invalid_sof;
+	u64 tx_timeout;
+};
+
+static const char mse102x_gstrings_stats[][ETH_GSTRING_LEN] = {
+	"SPI transfer errors",
+	"Invalid command",
+	"Invalid CTR",
+	"Invalid DFT",
+	"Invalid frame length",
+	"Invalid RTS",
+	"Invalid SOF",
+	"TX timeout",
+};
+
+struct mse102x_net {
+	struct net_device	*ndev;
+
+	u8			rxd[8];
+	u8			txd[8];
+
+	u32			msg_enable ____cacheline_aligned;
+
+	struct sk_buff_head	txq;
+	struct mse102x_stats	stats;
+};
+
+struct mse102x_net_spi {
+	struct mse102x_net	mse102x;
+	struct mutex		lock;		/* Protect SPI frame transfer */
+	struct work_struct	tx_work;
+	struct spi_device	*spidev;
+	struct spi_message	spi_msg;
+	struct spi_transfer	spi_xfer;
+
+#ifdef CONFIG_DEBUG_FS
+	struct dentry		*device_root;
+#endif
+};
+
+#define to_mse102x_spi(mse) container_of((mse), struct mse102x_net_spi, mse102x)
+
+#ifdef CONFIG_DEBUG_FS
+
+static int mse102x_info_show(struct seq_file *s, void *what)
+{
+	struct mse102x_net_spi *mses = s->private;
+
+	seq_printf(s, "TX ring size        : %u\n",
+		   skb_queue_len(&mses->mse102x.txq));
+
+	seq_printf(s, "IRQ                 : %d\n",
+		   mses->spidev->irq);
+
+	seq_printf(s, "SPI effective speed : %lu\n",
+		   (unsigned long)mses->spi_xfer.effective_speed_hz);
+	seq_printf(s, "SPI mode            : %x\n",
+		   mses->spidev->mode);
+
+	return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(mse102x_info);
+
+static void mse102x_init_device_debugfs(struct mse102x_net_spi *mses)
+{
+	mses->device_root = debugfs_create_dir(dev_name(&mses->mse102x.ndev->dev),
+					       NULL);
+
+	debugfs_create_file("info", S_IFREG | 0444, mses->device_root, mses,
+			    &mse102x_info_fops);
+}
+
+static void mse102x_remove_device_debugfs(struct mse102x_net_spi *mses)
+{
+	debugfs_remove_recursive(mses->device_root);
+}
+
+#else /* CONFIG_DEBUG_FS */
+
+static void mse102x_init_device_debugfs(struct mse102x_net_spi *mses)
+{
+}
+
+static void mse102x_remove_device_debugfs(struct mse102x_net_spi *mses)
+{
+}
+
+#endif
+
+/* SPI register read/write calls.
+ *
+ * All these calls issue SPI transactions to access the chip's registers. They
+ * all require that the necessary lock is held to prevent accesses when the
+ * chip is busy transferring packet data.
+ */
+
+static void mse102x_tx_cmd_spi(struct mse102x_net *mse, u16 cmd)
+{
+	struct mse102x_net_spi *mses = to_mse102x_spi(mse);
+	struct spi_transfer *xfer = &mses->spi_xfer;
+	struct spi_message *msg = &mses->spi_msg;
+	__be16 txb[2];
+	int ret;
+
+	txb[0] = cpu_to_be16(DET_CMD);
+	txb[1] = cpu_to_be16(cmd);
+
+	xfer->tx_buf = txb;
+	xfer->rx_buf = NULL;
+	xfer->len = DET_CMD_LEN;
+
+	ret = spi_sync(mses->spidev, msg);
+	if (ret < 0) {
+		netdev_err(mse->ndev, "%s: spi_sync() failed: %d\n",
+			   __func__, ret);
+		mse->stats.xfer_err++;
+	}
+}
+
+static int mse102x_rx_cmd_spi(struct mse102x_net *mse, u8 *rxb)
+{
+	struct mse102x_net_spi *mses = to_mse102x_spi(mse);
+	struct spi_transfer *xfer = &mses->spi_xfer;
+	struct spi_message *msg = &mses->spi_msg;
+	__be16 *txb = (__be16 *)mse->txd;
+	__be16 *cmd = (__be16 *)mse->rxd;
+	u8 *trx = mse->rxd;
+	int ret;
+
+	txb[0] = 0;
+	txb[1] = 0;
+
+	xfer->tx_buf = txb;
+	xfer->rx_buf = trx;
+	xfer->len = DET_CMD_LEN;
+
+	ret = spi_sync(mses->spidev, msg);
+	if (ret < 0) {
+		netdev_err(mse->ndev, "%s: spi_sync() failed: %d\n",
+			   __func__, ret);
+		mse->stats.xfer_err++;
+	} else if (*cmd != cpu_to_be16(DET_CMD)) {
+		net_dbg_ratelimited("%s: Unexpected response (0x%04x)\n",
+				    __func__, *cmd);
+		mse->stats.invalid_cmd++;
+		ret = -EIO;
+	} else {
+		memcpy(rxb, trx + 2, 2);
+	}
+
+	return ret;
+}
+
+static inline void mse102x_push_header(struct sk_buff *skb)
+{
+	__be16 *header = skb_push(skb, DET_SOF_LEN);
+
+	*header = cpu_to_be16(DET_SOF);
+}
+
+static inline void mse102x_put_footer(struct sk_buff *skb)
+{
+	__be16 *footer = skb_put(skb, DET_DFT_LEN);
+
+	*footer = cpu_to_be16(DET_DFT);
+}
+
+static int mse102x_tx_frame_spi(struct mse102x_net *mse, struct sk_buff *txp,
+				unsigned int pad)
+{
+	struct mse102x_net_spi *mses = to_mse102x_spi(mse);
+	struct spi_transfer *xfer = &mses->spi_xfer;
+	struct spi_message *msg = &mses->spi_msg;
+	struct sk_buff *tskb;
+	int ret;
+
+	netif_dbg(mse, tx_queued, mse->ndev, "%s: skb %p, %d@%p\n",
+		  __func__, txp, txp->len, txp->data);
+
+	if ((skb_headroom(txp) < DET_SOF_LEN) ||
+	    (skb_tailroom(txp) < DET_DFT_LEN + pad)) {
+		tskb = skb_copy_expand(txp, DET_SOF_LEN, DET_DFT_LEN + pad,
+				       GFP_KERNEL);
+		if (!tskb)
+			return -ENOMEM;
+
+		dev_kfree_skb(txp);
+		txp = tskb;
+	}
+
+	mse102x_push_header(txp);
+
+	if (pad)
+		skb_put_zero(txp, pad);
+
+	mse102x_put_footer(txp);
+
+	xfer->tx_buf = txp->data;
+	xfer->rx_buf = NULL;
+	xfer->len = txp->len;
+
+	ret = spi_sync(mses->spidev, msg);
+	if (ret < 0) {
+		netdev_err(mse->ndev, "%s: spi_sync() failed: %d\n",
+			   __func__, ret);
+		mse->stats.xfer_err++;
+	}
+
+	return ret;
+}
+
+static int mse102x_rx_frame_spi(struct mse102x_net *mse, u8 *buff,
+				unsigned int frame_len)
+{
+	struct mse102x_net_spi *mses = to_mse102x_spi(mse);
+	struct spi_transfer *xfer = &mses->spi_xfer;
+	struct spi_message *msg = &mses->spi_msg;
+	__be16 *sof = (__be16 *)buff;
+	__be16 *dft = (__be16 *)(buff + DET_SOF_LEN + frame_len);
+	int ret;
+
+	xfer->rx_buf = buff;
+	xfer->tx_buf = NULL;
+	xfer->len = DET_SOF_LEN + frame_len + DET_DFT_LEN;
+
+	ret = spi_sync(mses->spidev, msg);
+	if (ret < 0) {
+		netdev_err(mse->ndev, "%s: spi_sync() failed: %d\n",
+			   __func__, ret);
+		mse->stats.xfer_err++;
+	} else if (*sof != cpu_to_be16(DET_SOF)) {
+		netdev_dbg(mse->ndev, "%s: SPI start of frame is invalid (0x%04x)\n",
+			   __func__, *sof);
+		mse->stats.invalid_sof++;
+		ret = -EIO;
+	} else if (*dft != cpu_to_be16(DET_DFT)) {
+		netdev_dbg(mse->ndev, "%s: SPI frame tail is invalid (0x%04x)\n",
+			   __func__, *dft);
+		mse->stats.invalid_dft++;
+		ret = -EIO;
+	}
+
+	return ret;
+}
+
+static void mse102x_dump_packet(const char *msg, int len, const char *data)
+{
+	printk(KERN_DEBUG ": %s - packet len:%d\n", msg, len);
+	print_hex_dump(KERN_DEBUG, "pk data: ", DUMP_PREFIX_OFFSET, 16, 1,
+		       data, len, true);
+}
+
+static void mse102x_rx_pkt_spi(struct mse102x_net *mse)
+{
+	struct sk_buff *skb;
+	unsigned int rxalign;
+	unsigned int rxlen;
+	__be16 rx = 0;
+	u16 cmd_resp;
+	u8 *rxpkt;
+	int ret;
+
+	mse102x_tx_cmd_spi(mse, CMD_CTR);
+	ret = mse102x_rx_cmd_spi(mse, (u8 *)&rx);
+	cmd_resp = be16_to_cpu(rx);
+
+	if (ret || ((cmd_resp & CMD_MASK) != CMD_RTS)) {
+		usleep_range(50, 100);
+
+		mse102x_tx_cmd_spi(mse, CMD_CTR);
+		ret = mse102x_rx_cmd_spi(mse, (u8 *)&rx);
+		if (ret)
+			return;
+
+		cmd_resp = be16_to_cpu(rx);
+		if ((cmd_resp & CMD_MASK) != CMD_RTS) {
+			net_dbg_ratelimited("%s: Unexpected response (0x%04x)\n",
+					    __func__, cmd_resp);
+			mse->stats.invalid_rts++;
+			return;
+		}
+
+		net_dbg_ratelimited("%s: Unexpected response to first CMD\n",
+				    __func__);
+	}
+
+	rxlen = cmd_resp & LEN_MASK;
+	if (!rxlen) {
+		net_dbg_ratelimited("%s: No frame length defined\n", __func__);
+		mse->stats.invalid_len++;
+		return;
+	}
+
+	rxalign = ALIGN(rxlen + DET_SOF_LEN + DET_DFT_LEN, 4);
+	skb = netdev_alloc_skb_ip_align(mse->ndev, rxalign);
+	if (!skb)
+		return;
+
+	/* 2 bytes Start of frame (before ethernet header)
+	 * 2 bytes Data frame tail (after ethernet frame)
+	 * They are copied, but ignored.
+	 */
+	rxpkt = skb_put(skb, rxlen) - DET_SOF_LEN;
+	if (mse102x_rx_frame_spi(mse, rxpkt, rxlen)) {
+		mse->ndev->stats.rx_errors++;
+		dev_kfree_skb(skb);
+		return;
+	}
+
+	if (netif_msg_pktdata(mse))
+		mse102x_dump_packet(__func__, skb->len, skb->data);
+
+	skb->protocol = eth_type_trans(skb, mse->ndev);
+	netif_rx_ni(skb);
+
+	mse->ndev->stats.rx_packets++;
+	mse->ndev->stats.rx_bytes += rxlen;
+}
+
+static int mse102x_tx_pkt_spi(struct mse102x_net *mse, struct sk_buff *txb,
+			      unsigned long work_timeout)
+{
+	unsigned int pad = 0;
+	__be16 rx = 0;
+	u16 cmd_resp;
+	int ret;
+	bool first = true;
+
+	if (txb->len < 60)
+		pad = 60 - txb->len;
+
+	while (1) {
+		mse102x_tx_cmd_spi(mse, CMD_RTS | (txb->len + pad));
+		ret = mse102x_rx_cmd_spi(mse, (u8 *)&rx);
+		cmd_resp = be16_to_cpu(rx);
+
+		if (!ret) {
+			/* ready to send frame ? */
+			if (cmd_resp == CMD_CTR)
+				break;
+
+			net_dbg_ratelimited("%s: Unexpected response (0x%04x)\n",
+					    __func__, cmd_resp);
+			mse->stats.invalid_ctr++;
+		}
+
+		/* It's not predictable how long / many retries it takes to
+		 * send at least one packet, so TX timeouts are possible.
+		 * That's the reason why the netdev watchdog is not used here.
+		 */
+		if (time_after(jiffies, work_timeout))
+			return -ETIMEDOUT;
+
+		if (first) {
+			/* throttle at first issue */
+			netif_stop_queue(mse->ndev);
+			/* fast retry */
+			usleep_range(50, 100);
+			first = false;
+		} else {
+			msleep(20);
+		}
+	};
+
+	ret = mse102x_tx_frame_spi(mse, txb, pad);
+	if (ret)
+		net_dbg_ratelimited("%s: Failed to send (%d), drop frame\n",
+				    __func__, ret);
+
+	return ret;
+}
+
+#define TX_QUEUE_MAX 10
+
+static void mse102x_tx_work(struct work_struct *work)
+{
+	/* Make sure timeout is sufficient to transfer TX_QUEUE_MAX frames */
+	unsigned long work_timeout = jiffies + msecs_to_jiffies(1000);
+	struct mse102x_net_spi *mses;
+	struct mse102x_net *mse;
+	struct sk_buff *txb;
+	int ret = 0;
+
+	mses = container_of(work, struct mse102x_net_spi, tx_work);
+	mse = &mses->mse102x;
+
+	while ((txb = skb_dequeue(&mse->txq))) {
+		mutex_lock(&mses->lock);
+		ret = mse102x_tx_pkt_spi(mse, txb, work_timeout);
+		mutex_unlock(&mses->lock);
+		if (ret) {
+			mse->ndev->stats.tx_dropped++;
+		} else {
+			mse->ndev->stats.tx_bytes += txb->len;
+			mse->ndev->stats.tx_packets++;
+		}
+
+		dev_kfree_skb(txb);
+	}
+
+	if (ret == -ETIMEDOUT) {
+		if (netif_msg_timer(mse))
+			netdev_err(mse->ndev, "tx work timeout\n");
+
+		mse->stats.tx_timeout++;
+	}
+
+	netif_wake_queue(mse->ndev);
+}
+
+static netdev_tx_t mse102x_start_xmit_spi(struct sk_buff *skb,
+					  struct net_device *ndev)
+{
+	struct mse102x_net *mse = netdev_priv(ndev);
+	struct mse102x_net_spi *mses = to_mse102x_spi(mse);
+
+	netif_dbg(mse, tx_queued, ndev,
+		  "%s: skb %p, %d@%p\n", __func__, skb, skb->len, skb->data);
+
+	skb_queue_tail(&mse->txq, skb);
+
+	if (skb_queue_len(&mse->txq) >= TX_QUEUE_MAX)
+		netif_stop_queue(ndev);
+
+	schedule_work(&mses->tx_work);
+
+	return NETDEV_TX_OK;
+}
+
+static void mse102x_init_mac(struct mse102x_net *mse, struct device_node *np)
+{
+	struct net_device *ndev = mse->ndev;
+	int ret = of_get_ethdev_address(np, ndev);
+
+	if (ret) {
+		eth_hw_addr_random(ndev);
+		netdev_err(ndev, "Using random MAC address: %pM\n",
+			   ndev->dev_addr);
+	}
+}
+
+/* Assumption: this is called for every incoming packet */
+static irqreturn_t mse102x_irq(int irq, void *_mse)
+{
+	struct mse102x_net *mse = _mse;
+	struct mse102x_net_spi *mses = to_mse102x_spi(mse);
+
+	mutex_lock(&mses->lock);
+	mse102x_rx_pkt_spi(mse);
+	mutex_unlock(&mses->lock);
+
+	return IRQ_HANDLED;
+}
+
+static int mse102x_net_open(struct net_device *ndev)
+{
+	struct mse102x_net *mse = netdev_priv(ndev);
+	int ret;
+
+	ret = request_threaded_irq(ndev->irq, NULL, mse102x_irq, IRQF_ONESHOT,
+				   ndev->name, mse);
+	if (ret < 0) {
+		netdev_err(ndev, "Failed to get irq: %d\n", ret);
+		return ret;
+	}
+
+	netif_dbg(mse, ifup, ndev, "opening\n");
+
+	netif_start_queue(ndev);
+
+	netif_carrier_on(ndev);
+
+	netif_dbg(mse, ifup, ndev, "network device up\n");
+
+	return 0;
+}
+
+static int mse102x_net_stop(struct net_device *ndev)
+{
+	struct mse102x_net *mse = netdev_priv(ndev);
+	struct mse102x_net_spi *mses = to_mse102x_spi(mse);
+
+	netif_info(mse, ifdown, ndev, "shutting down\n");
+
+	netif_carrier_off(mse->ndev);
+
+	/* stop any outstanding work */
+	flush_work(&mses->tx_work);
+
+	netif_stop_queue(ndev);
+
+	skb_queue_purge(&mse->txq);
+
+	free_irq(ndev->irq, mse);
+
+	return 0;
+}
+
+static const struct net_device_ops mse102x_netdev_ops = {
+	.ndo_open		= mse102x_net_open,
+	.ndo_stop		= mse102x_net_stop,
+	.ndo_start_xmit		= mse102x_start_xmit_spi,
+	.ndo_set_mac_address	= eth_mac_addr,
+	.ndo_validate_addr	= eth_validate_addr,
+};
+
+/* ethtool support */
+
+static void mse102x_get_drvinfo(struct net_device *ndev,
+				struct ethtool_drvinfo *di)
+{
+	strscpy(di->driver, DRV_NAME, sizeof(di->driver));
+	strscpy(di->bus_info, dev_name(ndev->dev.parent), sizeof(di->bus_info));
+}
+
+static u32 mse102x_get_msglevel(struct net_device *ndev)
+{
+	struct mse102x_net *mse = netdev_priv(ndev);
+
+	return mse->msg_enable;
+}
+
+static void mse102x_set_msglevel(struct net_device *ndev, u32 to)
+{
+	struct mse102x_net *mse = netdev_priv(ndev);
+
+	mse->msg_enable = to;
+}
+
+static void mse102x_get_ethtool_stats(struct net_device *ndev,
+				      struct ethtool_stats *estats, u64 *data)
+{
+	struct mse102x_net *mse = netdev_priv(ndev);
+	struct mse102x_stats *st = &mse->stats;
+
+	memcpy(data, st, ARRAY_SIZE(mse102x_gstrings_stats) * sizeof(u64));
+}
+
+static void mse102x_get_strings(struct net_device *ndev, u32 stringset, u8 *buf)
+{
+	switch (stringset) {
+	case ETH_SS_STATS:
+		memcpy(buf, &mse102x_gstrings_stats,
+		       sizeof(mse102x_gstrings_stats));
+		break;
+	default:
+		WARN_ON(1);
+		break;
+	}
+}
+
+static int mse102x_get_sset_count(struct net_device *ndev, int sset)
+{
+	switch (sset) {
+	case ETH_SS_STATS:
+		return ARRAY_SIZE(mse102x_gstrings_stats);
+	default:
+		return -EINVAL;
+	}
+}
+
+static const struct ethtool_ops mse102x_ethtool_ops = {
+	.get_drvinfo		= mse102x_get_drvinfo,
+	.get_link		= ethtool_op_get_link,
+	.get_msglevel		= mse102x_get_msglevel,
+	.set_msglevel		= mse102x_set_msglevel,
+	.get_ethtool_stats	= mse102x_get_ethtool_stats,
+	.get_strings		= mse102x_get_strings,
+	.get_sset_count		= mse102x_get_sset_count,
+};
+
+/* driver bus management functions */
+
+#ifdef CONFIG_PM_SLEEP
+
+static int mse102x_suspend(struct device *dev)
+{
+	struct mse102x_net *mse = dev_get_drvdata(dev);
+	struct net_device *ndev = mse->ndev;
+
+	if (netif_running(ndev)) {
+		netif_device_detach(ndev);
+		mse102x_net_stop(ndev);
+	}
+
+	return 0;
+}
+
+static int mse102x_resume(struct device *dev)
+{
+	struct mse102x_net *mse = dev_get_drvdata(dev);
+	struct net_device *ndev = mse->ndev;
+
+	if (netif_running(ndev)) {
+		mse102x_net_open(ndev);
+		netif_device_attach(ndev);
+	}
+
+	return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(mse102x_pm_ops, mse102x_suspend, mse102x_resume);
+
+static int mse102x_probe_spi(struct spi_device *spi)
+{
+	struct device *dev = &spi->dev;
+	struct mse102x_net_spi *mses;
+	struct net_device *ndev;
+	struct mse102x_net *mse;
+	int ret;
+
+	spi->bits_per_word = 8;
+	spi->mode |= SPI_MODE_3;
+	/* enforce minimum speed to ensure device functionality */
+	spi->master->min_speed_hz = MIN_FREQ_HZ;
+
+	if (!spi->max_speed_hz)
+		spi->max_speed_hz = MAX_FREQ_HZ;
+
+	if (spi->max_speed_hz < MIN_FREQ_HZ ||
+	    spi->max_speed_hz > MAX_FREQ_HZ) {
+		dev_err(&spi->dev, "SPI max frequency out of range (min: %u, max: %u)\n",
+			MIN_FREQ_HZ, MAX_FREQ_HZ);
+		return -EINVAL;
+	}
+
+	ret = spi_setup(spi);
+	if (ret < 0) {
+		dev_err(&spi->dev, "Unable to setup SPI device: %d\n", ret);
+		return ret;
+	}
+
+	ndev = devm_alloc_etherdev(dev, sizeof(struct mse102x_net_spi));
+	if (!ndev)
+		return -ENOMEM;
+
+	ndev->needed_tailroom += ALIGN(DET_DFT_LEN, 4);
+	ndev->needed_headroom += ALIGN(DET_SOF_LEN, 4);
+	ndev->priv_flags &= ~IFF_TX_SKB_SHARING;
+	ndev->tx_queue_len = 100;
+
+	mse = netdev_priv(ndev);
+	mses = to_mse102x_spi(mse);
+
+	mses->spidev = spi;
+	mutex_init(&mses->lock);
+	INIT_WORK(&mses->tx_work, mse102x_tx_work);
+
+	/* initialise pre-made spi transfer messages */
+	spi_message_init(&mses->spi_msg);
+	spi_message_add_tail(&mses->spi_xfer, &mses->spi_msg);
+
+	ndev->irq = spi->irq;
+	mse->ndev = ndev;
+
+	/* set the default message enable */
+	mse->msg_enable = netif_msg_init(-1, MSG_DEFAULT);
+
+	skb_queue_head_init(&mse->txq);
+
+	SET_NETDEV_DEV(ndev, dev);
+
+	dev_set_drvdata(dev, mse);
+
+	netif_carrier_off(mse->ndev);
+	ndev->if_port = IF_PORT_HOMEPLUG;
+	ndev->netdev_ops = &mse102x_netdev_ops;
+	ndev->ethtool_ops = &mse102x_ethtool_ops;
+
+	mse102x_init_mac(mse, dev->of_node);
+
+	ret = register_netdev(ndev);
+	if (ret) {
+		dev_err(dev, "failed to register network device: %d\n", ret);
+		return ret;
+	}
+
+	mse102x_init_device_debugfs(mses);
+
+	return 0;
+}
+
+static int mse102x_remove_spi(struct spi_device *spi)
+{
+	struct mse102x_net *mse = dev_get_drvdata(&spi->dev);
+	struct mse102x_net_spi *mses = to_mse102x_spi(mse);
+
+	if (netif_msg_drv(mse))
+		dev_info(&spi->dev, "remove\n");
+
+	mse102x_remove_device_debugfs(mses);
+	unregister_netdev(mse->ndev);
+
+	return 0;
+}
+
+static const struct of_device_id mse102x_match_table[] = {
+	{ .compatible = "vertexcom,mse1021" },
+	{ .compatible = "vertexcom,mse1022" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, mse102x_match_table);
+
+static struct spi_driver mse102x_driver = {
+	.driver = {
+		.name = DRV_NAME,
+		.of_match_table = mse102x_match_table,
+		.pm = &mse102x_pm_ops,
+	},
+	.probe = mse102x_probe_spi,
+	.remove = mse102x_remove_spi,
+};
+module_spi_driver(mse102x_driver);
+
+MODULE_DESCRIPTION("MSE102x Network driver");
+MODULE_AUTHOR("Stefan Wahren <stefan.wahren@in-tech.com>");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("spi:" DRV_NAME);
-- 
2.7.4

Re: [PATCH RFC V2 3/4] net: introduce media selection IF_PORT_HOMEPLUG

[Jakub Kicinski]

On Sat,  4 Dec 2021 14:17:50 +0100 Stefan Wahren wrote:
> Introduce a new media selection dedicated for HomePlug powerline
> communication. This allows us to use the proper if_port setting in
> HomePlug drivers.
> 
> Suggested-by: Andrew Lunn <andrew@lunn.ch>
> Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>

I _think_ the IF_PORT API is an very ancient (Linux 2.2) way of
switching ports on early Ethernet cards. Isn't it? It predates
ethtool and all the modern interfaces. Quick grep seems to indicate
it's accessed only for old HW as well.

Do you have a use case for setting it?

> diff --git a/include/uapi/linux/netdevice.h b/include/uapi/linux/netdevice.h
> index f3770c5..0f1f536 100644
> --- a/include/uapi/linux/netdevice.h
> +++ b/include/uapi/linux/netdevice.h
> @@ -53,7 +53,8 @@ enum {
>          IF_PORT_AUI,
>          IF_PORT_100BASET,
>          IF_PORT_100BASETX,
> -        IF_PORT_100BASEFX
> +        IF_PORT_100BASEFX,
> +        IF_PORT_HOMEPLUG
>  };
>  
>  /* hardware address assignment types */

Re: [PATCH RFC V2 3/4] net: introduce media selection IF_PORT_HOMEPLUG

[Stefan Wahren]

Am 06.12.21 um 20:29 schrieb Jakub Kicinski:
> On Sat,  4 Dec 2021 14:17:50 +0100 Stefan Wahren wrote:
>> Introduce a new media selection dedicated for HomePlug powerline
>> communication. This allows us to use the proper if_port setting in
>> HomePlug drivers.
>>
>> Suggested-by: Andrew Lunn <andrew@lunn.ch>
>> Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
> I _think_ the IF_PORT API is an very ancient (Linux 2.2) way of
> switching ports on early Ethernet cards. Isn't it? It predates
> ethtool and all the modern interfaces. Quick grep seems to indicate
> it's accessed only for old HW as well.
>
> Do you have a use case for setting it?
Actually not, i will drop it from the patchset.