net: Microchip encx24j600 driver

This ethernet driver supports the Micorchip enc424j600/626j600 Ethernet
controller over a SPI bus interface. This driver makes use of the regmap API to
optimize access to registers by caching registers where possible.

Datasheet:
http://ww1.microchip.com/downloads/en/DeviceDoc/39935b.pdf

Signed-off-by: Jon Ringle <jringle@gridpoint.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 1127 insertions, 0 deletions

diff --git a/drivers/net/ethernet/microchip/encx24j600.c b/drivers/net/ethernet/microchip/encx24j600.c
new file mode 100644
index 000000000000..e1329d9c2acc
--- /dev/null
+++ b/drivers/net/ethernet/microchip/encx24j600.c
@@ -0,0 +1,1127 @@
+/**
+ * Microchip ENCX24J600 ethernet driver
+ *
+ * Copyright (C) 2015 Gridpoint
+ * Author: Jon Ringle <jringle@gridpoint.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ */
+
+#include <linux/device.h>
+#include <linux/errno.h>
+#include <linux/etherdevice.h>
+#include <linux/ethtool.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/netdevice.h>
+#include <linux/regmap.h>
+#include <linux/skbuff.h>
+#include <linux/spi/spi.h>
+
+#include "encx24j600_hw.h"
+
+#define DRV_NAME	"encx24j600"
+#define DRV_VERSION	"1.0"
+
+#define DEFAULT_MSG_ENABLE (NETIF_MSG_DRV | NETIF_MSG_PROBE | NETIF_MSG_LINK)
+static int debug = -1;
+module_param(debug, int, 0);
+MODULE_PARM_DESC(debug, "Debug level (0=none,...,16=all)");
+
+/* SRAM memory layout:
+ *
+ * 0x0000-0x05ff TX buffers  1.5KB  (1*1536) reside in the GP area in SRAM
+ * 0x0600-0x5fff RX buffers 22.5KB (15*1536) reside in the RX area in SRAM
+ */
+#define ENC_TX_BUF_START 0x0000U
+#define ENC_RX_BUF_START 0x0600U
+#define ENC_RX_BUF_END   0x5fffU
+#define ENC_SRAM_SIZE    0x6000U
+
+enum {
+	RXFILTER_NORMAL,
+	RXFILTER_MULTI,
+	RXFILTER_PROMISC
+};
+
+struct encx24j600_priv {
+	struct net_device        *ndev;
+	struct mutex              lock; /* device access lock */
+	struct encx24j600_context ctx;
+	struct sk_buff           *tx_skb;
+	struct task_struct       *kworker_task;
+	struct kthread_worker     kworker;
+	struct kthread_work       tx_work;
+	struct kthread_work       setrx_work;
+	u16                       next_packet;
+	bool                      hw_enabled;
+	bool                      full_duplex;
+	bool                      autoneg;
+	u16                       speed;
+	int                       rxfilter;
+	u32                       msg_enable;
+};
+
+static void dump_packet(const char *msg, int len, const char *data)
+{
+	pr_debug(DRV_NAME ": %s - packet len:%d\n", msg, len);
+	print_hex_dump_bytes("pk data: ", DUMP_PREFIX_OFFSET, data, len);
+}
+
+static void encx24j600_dump_rsv(struct encx24j600_priv *priv, const char *msg,
+				struct rsv *rsv)
+{
+	struct net_device *dev = priv->ndev;
+
+	netdev_info(dev, "RX packet Len:%d\n", rsv->len);
+	netdev_dbg(dev, "%s - NextPk: 0x%04x\n", msg,
+		   rsv->next_packet);
+	netdev_dbg(dev, "RxOK: %d, DribbleNibble: %d\n",
+		   RSV_GETBIT(rsv->rxstat, RSV_RXOK),
+		   RSV_GETBIT(rsv->rxstat, RSV_DRIBBLENIBBLE));
+	netdev_dbg(dev, "CRCErr:%d, LenChkErr: %d, LenOutOfRange: %d\n",
+		   RSV_GETBIT(rsv->rxstat, RSV_CRCERROR),
+		   RSV_GETBIT(rsv->rxstat, RSV_LENCHECKERR),
+		   RSV_GETBIT(rsv->rxstat, RSV_LENOUTOFRANGE));
+	netdev_dbg(dev, "Multicast: %d, Broadcast: %d, LongDropEvent: %d, CarrierEvent: %d\n",
+		   RSV_GETBIT(rsv->rxstat, RSV_RXMULTICAST),
+		   RSV_GETBIT(rsv->rxstat, RSV_RXBROADCAST),
+		   RSV_GETBIT(rsv->rxstat, RSV_RXLONGEVDROPEV),
+		   RSV_GETBIT(rsv->rxstat, RSV_CARRIEREV));
+	netdev_dbg(dev, "ControlFrame: %d, PauseFrame: %d, UnknownOp: %d, VLanTagFrame: %d\n",
+		   RSV_GETBIT(rsv->rxstat, RSV_RXCONTROLFRAME),
+		   RSV_GETBIT(rsv->rxstat, RSV_RXPAUSEFRAME),
+		   RSV_GETBIT(rsv->rxstat, RSV_RXUNKNOWNOPCODE),
+		   RSV_GETBIT(rsv->rxstat, RSV_RXTYPEVLAN));
+}
+
+static u16 encx24j600_read_reg(struct encx24j600_priv *priv, u8 reg)
+{
+	struct net_device *dev = priv->ndev;
+	unsigned int val = 0;
+	int ret = regmap_read(priv->ctx.regmap, reg, &val);
+	if (unlikely(ret))
+		netif_err(priv, drv, dev, "%s: error %d reading reg %02x\n",
+			  __func__, ret, reg);
+	return val;
+}
+
+static void encx24j600_write_reg(struct encx24j600_priv *priv, u8 reg, u16 val)
+{
+	struct net_device *dev = priv->ndev;
+	int ret = regmap_write(priv->ctx.regmap, reg, val);
+	if (unlikely(ret))
+		netif_err(priv, drv, dev, "%s: error %d writing reg %02x=%04x\n",
+			  __func__, ret, reg, val);
+}
+
+static void encx24j600_update_reg(struct encx24j600_priv *priv, u8 reg,
+				  u16 mask, u16 val)
+{
+	struct net_device *dev = priv->ndev;
+	int ret = regmap_update_bits(priv->ctx.regmap, reg, mask, val);
+	if (unlikely(ret))
+		netif_err(priv, drv, dev, "%s: error %d updating reg %02x=%04x~%04x\n",
+			  __func__, ret, reg, val, mask);
+}
+
+static u16 encx24j600_read_phy(struct encx24j600_priv *priv, u8 reg)
+{
+	struct net_device *dev = priv->ndev;
+	unsigned int val = 0;
+	int ret = regmap_read(priv->ctx.phymap, reg, &val);
+	if (unlikely(ret))
+		netif_err(priv, drv, dev, "%s: error %d reading %02x\n",
+			  __func__, ret, reg);
+	return val;
+}
+
+static void encx24j600_write_phy(struct encx24j600_priv *priv, u8 reg, u16 val)
+{
+	struct net_device *dev = priv->ndev;
+	int ret = regmap_write(priv->ctx.phymap, reg, val);
+	if (unlikely(ret))
+		netif_err(priv, drv, dev, "%s: error %d writing reg %02x=%04x\n",
+			  __func__, ret, reg, val);
+}
+
+static void encx24j600_clr_bits(struct encx24j600_priv *priv, u8 reg, u16 mask)
+{
+	encx24j600_update_reg(priv, reg, mask, 0);
+}
+
+static void encx24j600_set_bits(struct encx24j600_priv *priv, u8 reg, u16 mask)
+{
+	encx24j600_update_reg(priv, reg, mask, mask);
+}
+
+static void encx24j600_cmd(struct encx24j600_priv *priv, u8 cmd)
+{
+	struct net_device *dev = priv->ndev;
+	int ret = regmap_write(priv->ctx.regmap, cmd, 0);
+	if (unlikely(ret))
+		netif_err(priv, drv, dev, "%s: error %d with cmd %02x\n",
+			  __func__, ret, cmd);
+}
+
+static int encx24j600_raw_read(struct encx24j600_priv *priv, u8 reg, u8 *data,
+			       size_t count)
+{
+	int ret;
+	mutex_lock(&priv->ctx.mutex);
+	ret = regmap_encx24j600_spi_read(&priv->ctx, reg, data, count);
+	mutex_unlock(&priv->ctx.mutex);
+
+	return ret;
+}
+
+static int encx24j600_raw_write(struct encx24j600_priv *priv, u8 reg,
+				const u8 *data, size_t count)
+{
+	int ret;
+	mutex_lock(&priv->ctx.mutex);
+	ret = regmap_encx24j600_spi_write(&priv->ctx, reg, data, count);
+	mutex_unlock(&priv->ctx.mutex);
+
+	return ret;
+}
+
+static void encx24j600_update_phcon1(struct encx24j600_priv *priv)
+{
+	u16 phcon1 = encx24j600_read_phy(priv, PHCON1);
+	if (priv->autoneg == AUTONEG_ENABLE) {
+		phcon1 |= ANEN | RENEG;
+	} else {
+		phcon1 &= ~ANEN;
+		if (priv->speed == SPEED_100)
+			phcon1 |= SPD100;
+		else
+			phcon1 &= ~SPD100;
+
+		if (priv->full_duplex)
+			phcon1 |= PFULDPX;
+		else
+			phcon1 &= ~PFULDPX;
+	}
+	encx24j600_write_phy(priv, PHCON1, phcon1);
+}
+
+/* Waits for autonegotiation to complete. */
+static int encx24j600_wait_for_autoneg(struct encx24j600_priv *priv)
+{
+	struct net_device *dev = priv->ndev;
+	unsigned long timeout = jiffies + msecs_to_jiffies(2000);
+	u16 phstat1;
+	u16 estat;
+	int ret = 0;
+
+	phstat1 = encx24j600_read_phy(priv, PHSTAT1);
+	while ((phstat1 & ANDONE) == 0) {
+		if (time_after(jiffies, timeout)) {
+			u16 phstat3;
+
+			netif_notice(priv, drv, dev, "timeout waiting for autoneg done\n");
+
+			priv->autoneg = AUTONEG_DISABLE;
+			phstat3 = encx24j600_read_phy(priv, PHSTAT3);
+			priv->speed = (phstat3 & PHY3SPD100)
+				      ? SPEED_100 : SPEED_10;
+			priv->full_duplex = (phstat3 & PHY3DPX) ? 1 : 0;
+			encx24j600_update_phcon1(priv);
+			netif_notice(priv, drv, dev, "Using parallel detection: %s/%s",
+				     priv->speed == SPEED_100 ? "100" : "10",
+				     priv->full_duplex ? "Full" : "Half");
+
+			return -ETIMEDOUT;
+		}
+		cpu_relax();
+		phstat1 = encx24j600_read_phy(priv, PHSTAT1);
+	}
+
+	estat = encx24j600_read_reg(priv, ESTAT);
+	if (estat & PHYDPX) {
+		encx24j600_set_bits(priv, MACON2, FULDPX);
+		encx24j600_write_reg(priv, MABBIPG, 0x15);
+	} else {
+		encx24j600_clr_bits(priv, MACON2, FULDPX);
+		encx24j600_write_reg(priv, MABBIPG, 0x12);
+		/* Max retransmittions attempt  */
+		encx24j600_write_reg(priv, MACLCON, 0x370f);
+	}
+
+	return ret;
+}
+
+/* Access the PHY to determine link status */
+static void encx24j600_check_link_status(struct encx24j600_priv *priv)
+{
+	struct net_device *dev = priv->ndev;
+	u16 estat;
+
+	estat = encx24j600_read_reg(priv, ESTAT);
+
+	if (estat & PHYLNK) {
+		if (priv->autoneg == AUTONEG_ENABLE)
+			encx24j600_wait_for_autoneg(priv);
+
+		netif_carrier_on(dev);
+		netif_info(priv, ifup, dev, "link up\n");
+	} else {
+		netif_info(priv, ifdown, dev, "link down\n");
+
+		/* Re-enable autoneg since we won't know what we might be
+		 * connected to when the link is brought back up again.
+		 */
+		priv->autoneg  = AUTONEG_ENABLE;
+		priv->full_duplex = true;
+		priv->speed = SPEED_100;
+		netif_carrier_off(dev);
+	}
+}
+
+static void encx24j600_int_link_handler(struct encx24j600_priv *priv)
+{
+	struct net_device *dev = priv->ndev;
+
+	netif_dbg(priv, intr, dev, "%s", __func__);
+	encx24j600_check_link_status(priv);
+	encx24j600_clr_bits(priv, EIR, LINKIF);
+}
+
+static void encx24j600_tx_complete(struct encx24j600_priv *priv, bool err)
+{
+	struct net_device *dev = priv->ndev;
+
+	if (!priv->tx_skb) {
+		BUG();
+		return;
+	}
+
+	mutex_lock(&priv->lock);
+
+	if (err)
+		dev->stats.tx_errors++;
+	else
+		dev->stats.tx_packets++;
+
+	dev->stats.tx_bytes += priv->tx_skb->len;
+
+	encx24j600_clr_bits(priv, EIR, TXIF | TXABTIF);
+
+	netif_dbg(priv, tx_done, dev, "TX Done%s\n", err ? ": Err" : "");
+
+	dev_kfree_skb(priv->tx_skb);
+	priv->tx_skb = NULL;
+
+	netif_wake_queue(dev);
+
+	mutex_unlock(&priv->lock);
+}
+
+static int encx24j600_receive_packet(struct encx24j600_priv *priv,
+				     struct rsv *rsv)
+{
+	struct net_device *dev = priv->ndev;
+	struct sk_buff *skb = netdev_alloc_skb(dev, rsv->len + NET_IP_ALIGN);
+	if (!skb) {
+		pr_err_ratelimited("RX: OOM: packet dropped\n");
+		dev->stats.rx_dropped++;
+		return -ENOMEM;
+	}
+	skb_reserve(skb, NET_IP_ALIGN);
+	encx24j600_raw_read(priv, RRXDATA, skb_put(skb, rsv->len), rsv->len);
+
+	if (netif_msg_pktdata(priv))
+		dump_packet("RX", skb->len, skb->data);
+
+	skb->dev = dev;
+	skb->protocol = eth_type_trans(skb, dev);
+	skb->ip_summed = CHECKSUM_COMPLETE;
+
+	/* Maintain stats */
+	dev->stats.rx_packets++;
+	dev->stats.rx_bytes += rsv->len;
+	priv->next_packet = rsv->next_packet;
+
+	netif_rx(skb);
+
+	return 0;
+}
+
+static void encx24j600_rx_packets(struct encx24j600_priv *priv, u8 packet_count)
+{
+	struct net_device *dev = priv->ndev;
+
+	while (packet_count--) {
+		struct rsv rsv;
+		u16 newrxtail;
+
+		encx24j600_write_reg(priv, ERXRDPT, priv->next_packet);
+		encx24j600_raw_read(priv, RRXDATA, (u8 *)&rsv, sizeof(rsv));
+
+		if (netif_msg_rx_status(priv))
+			encx24j600_dump_rsv(priv, __func__, &rsv);
+
+		if (!RSV_GETBIT(rsv.rxstat, RSV_RXOK) ||
+		    (rsv.len > MAX_FRAMELEN)) {
+			netif_err(priv, rx_err, dev, "RX Error %04x\n",
+				  rsv.rxstat);
+			dev->stats.rx_errors++;
+
+			if (RSV_GETBIT(rsv.rxstat, RSV_CRCERROR))
+				dev->stats.rx_crc_errors++;
+			if (RSV_GETBIT(rsv.rxstat, RSV_LENCHECKERR))
+				dev->stats.rx_frame_errors++;
+			if (rsv.len > MAX_FRAMELEN)
+				dev->stats.rx_over_errors++;
+		} else {
+			encx24j600_receive_packet(priv, &rsv);
+		}
+
+		newrxtail = priv->next_packet - 2;
+		if (newrxtail == ENC_RX_BUF_START)
+			newrxtail = SRAM_SIZE - 2;
+
+		encx24j600_cmd(priv, SETPKTDEC);
+		encx24j600_write_reg(priv, ERXTAIL, newrxtail);
+	}
+}
+
+static irqreturn_t encx24j600_isr(int irq, void *dev_id)
+{
+	struct encx24j600_priv *priv = dev_id;
+	struct net_device *dev = priv->ndev;
+	int eir;
+
+	/* Clear interrupts */
+	encx24j600_cmd(priv, CLREIE);
+
+	eir = encx24j600_read_reg(priv, EIR);
+
+	if (eir & LINKIF)
+		encx24j600_int_link_handler(priv);
+
+	if (eir & TXIF)
+		encx24j600_tx_complete(priv, false);
+
+	if (eir & TXABTIF)
+		encx24j600_tx_complete(priv, true);
+
+	if (eir & RXABTIF) {
+		if (eir & PCFULIF) {
+			/* Packet counter is full */
+			netif_err(priv, rx_err, dev, "Packet counter full\n");
+		}
+		dev->stats.rx_dropped++;
+		encx24j600_clr_bits(priv, EIR, RXABTIF);
+	}
+
+	if (eir & PKTIF) {
+		u8 packet_count;
+
+		mutex_lock(&priv->lock);
+
+		packet_count = encx24j600_read_reg(priv, ESTAT) & 0xff;
+		while (packet_count) {
+			encx24j600_rx_packets(priv, packet_count);
+			packet_count = encx24j600_read_reg(priv, ESTAT) & 0xff;
+		}
+
+		mutex_unlock(&priv->lock);
+	}
+
+	/* Enable interrupts */
+	encx24j600_cmd(priv, SETEIE);
+
+	return IRQ_HANDLED;
+}
+
+static int encx24j600_soft_reset(struct encx24j600_priv *priv)
+{
+	int ret = 0;
+	int timeout;
+	u16 eudast;
+
+	/* Write and verify a test value to EUDAST */
+	regcache_cache_bypass(priv->ctx.regmap, true);
+	timeout = 10;
+	do {
+		encx24j600_write_reg(priv, EUDAST, EUDAST_TEST_VAL);
+		eudast = encx24j600_read_reg(priv, EUDAST);
+		usleep_range(25, 100);
+	} while ((eudast != EUDAST_TEST_VAL) && --timeout);
+	regcache_cache_bypass(priv->ctx.regmap, false);
+
+	if (timeout == 0) {
+		ret = -ETIMEDOUT;
+		goto err_out;
+	}
+
+	/* Wait for CLKRDY to become set */
+	timeout = 10;
+	while (!(encx24j600_read_reg(priv, ESTAT) & CLKRDY) && --timeout)
+		usleep_range(25, 100);
+
+	if (timeout == 0) {
+		ret = -ETIMEDOUT;
+		goto err_out;
+	}
+
+	/* Issue a System Reset command */
+	encx24j600_cmd(priv, SETETHRST);
+	usleep_range(25, 100);
+
+	/* Confirm that EUDAST has 0000h after system reset */
+	if (encx24j600_read_reg(priv, EUDAST) != 0) {
+		ret = -EINVAL;
+		goto err_out;
+	}
+
+	/* Wait for PHY register and status bits to become available */
+	usleep_range(256, 1000);
+
+err_out:
+	return ret;
+}
+
+static int encx24j600_hw_reset(struct encx24j600_priv *priv)
+{
+	int ret;
+
+	mutex_lock(&priv->lock);
+	ret = encx24j600_soft_reset(priv);
+	mutex_unlock(&priv->lock);
+
+	return ret;
+}
+
+static void encx24j600_reset_hw_tx(struct encx24j600_priv *priv)
+{
+	encx24j600_set_bits(priv, ECON2, TXRST);
+	encx24j600_clr_bits(priv, ECON2, TXRST);
+}
+
+static void encx24j600_hw_init_tx(struct encx24j600_priv *priv)
+{
+	/* Reset TX */
+	encx24j600_reset_hw_tx(priv);
+
+	/* Clear the TXIF flag if were previously set */
+	encx24j600_clr_bits(priv, EIR, TXIF | TXABTIF);
+
+	/* Write the Tx Buffer pointer */
+	encx24j600_write_reg(priv, EGPWRPT, ENC_TX_BUF_START);
+}
+
+static void encx24j600_hw_init_rx(struct encx24j600_priv *priv)
+{
+	encx24j600_cmd(priv, DISABLERX);
+
+	/* Set up RX packet start address in the SRAM */
+	encx24j600_write_reg(priv, ERXST, ENC_RX_BUF_START);
+
+	/* Preload the RX Data pointer to the beginning of the RX area */
+	encx24j600_write_reg(priv, ERXRDPT, ENC_RX_BUF_START);
+
+	priv->next_packet = ENC_RX_BUF_START;
+
+	/* Set up RX end address in the SRAM */
+	encx24j600_write_reg(priv, ERXTAIL, ENC_SRAM_SIZE - 2);
+
+	/* Reset the  user data pointers    */
+	encx24j600_write_reg(priv, EUDAST, ENC_SRAM_SIZE);
+	encx24j600_write_reg(priv, EUDAND, ENC_SRAM_SIZE + 1);
+
+	/* Set Max Frame length */
+	encx24j600_write_reg(priv, MAMXFL, MAX_FRAMELEN);
+}
+
+static void encx24j600_dump_config(struct encx24j600_priv *priv,
+				   const char *msg)
+{
+	pr_info(DRV_NAME ": %s\n", msg);
+
+	/* CHIP configuration */
+	pr_info(DRV_NAME " ECON1:   %04X\n", encx24j600_read_reg(priv, ECON1));
+	pr_info(DRV_NAME " ECON2:   %04X\n", encx24j600_read_reg(priv, ECON2));
+	pr_info(DRV_NAME " ERXFCON: %04X\n", encx24j600_read_reg(priv,
+								 ERXFCON));
+	pr_info(DRV_NAME " ESTAT:   %04X\n", encx24j600_read_reg(priv, ESTAT));
+	pr_info(DRV_NAME " EIR:     %04X\n", encx24j600_read_reg(priv, EIR));
+	pr_info(DRV_NAME " EIDLED:  %04X\n", encx24j600_read_reg(priv, EIDLED));
+
+	/* MAC layer configuration */
+	pr_info(DRV_NAME " MACON1:  %04X\n", encx24j600_read_reg(priv, MACON1));
+	pr_info(DRV_NAME " MACON2:  %04X\n", encx24j600_read_reg(priv, MACON2));
+	pr_info(DRV_NAME " MAIPG:   %04X\n", encx24j600_read_reg(priv, MAIPG));
+	pr_info(DRV_NAME " MACLCON: %04X\n", encx24j600_read_reg(priv,
+								 MACLCON));
+	pr_info(DRV_NAME " MABBIPG: %04X\n", encx24j600_read_reg(priv,
+								 MABBIPG));
+
+	/* PHY configuation */
+	pr_info(DRV_NAME " PHCON1:  %04X\n", encx24j600_read_phy(priv, PHCON1));
+	pr_info(DRV_NAME " PHCON2:  %04X\n", encx24j600_read_phy(priv, PHCON2));
+	pr_info(DRV_NAME " PHANA:   %04X\n", encx24j600_read_phy(priv, PHANA));
+	pr_info(DRV_NAME " PHANLPA: %04X\n", encx24j600_read_phy(priv,
+								 PHANLPA));
+	pr_info(DRV_NAME " PHANE:   %04X\n", encx24j600_read_phy(priv, PHANE));
+	pr_info(DRV_NAME " PHSTAT1: %04X\n", encx24j600_read_phy(priv,
+								 PHSTAT1));
+	pr_info(DRV_NAME " PHSTAT2: %04X\n", encx24j600_read_phy(priv,
+								 PHSTAT2));
+	pr_info(DRV_NAME " PHSTAT3: %04X\n", encx24j600_read_phy(priv,
+								 PHSTAT3));
+}
+
+static void encx24j600_set_rxfilter_mode(struct encx24j600_priv *priv)
+{
+	switch (priv->rxfilter) {
+	case RXFILTER_PROMISC:
+		encx24j600_set_bits(priv, MACON1, PASSALL);
+		encx24j600_write_reg(priv, ERXFCON, UCEN | MCEN | NOTMEEN);
+		break;
+	case RXFILTER_MULTI:
+		encx24j600_clr_bits(priv, MACON1, PASSALL);
+		encx24j600_write_reg(priv, ERXFCON, UCEN | CRCEN | BCEN | MCEN);
+		break;
+	case RXFILTER_NORMAL:
+	default:
+		encx24j600_clr_bits(priv, MACON1, PASSALL);
+		encx24j600_write_reg(priv, ERXFCON, UCEN | CRCEN | BCEN);
+		break;
+	}
+}
+
+static int encx24j600_hw_init(struct encx24j600_priv *priv)
+{
+	struct net_device *dev = priv->ndev;
+	int ret = 0;
+	u16 eidled;
+	u16 macon2;
+
+	priv->hw_enabled = false;
+
+	eidled = encx24j600_read_reg(priv, EIDLED);
+	if (((eidled & DEVID_MASK) >> DEVID_SHIFT) != ENCX24J600_DEV_ID) {
+		ret = -EINVAL;
+		goto err_out;
+	}
+
+	netif_info(priv, drv, dev, "Silicon rev ID: 0x%02x\n",
+		   (eidled & REVID_MASK) >> REVID_SHIFT);
+
+	/* PHY Leds: link status,
+	 * LEDA: Link + transmit/receive events
+	 * LEDB: Link State + colision events
+	 */
+	encx24j600_update_reg(priv, EIDLED, 0xbc00, 0xbc00);
+
+	/* Loopback disabled */
+	encx24j600_write_reg(priv, MACON1, 0x9);
+
+	/* interpacket gap value */
+	encx24j600_write_reg(priv, MAIPG, 0x0c12);
+
+	/* Write the auto negotiation pattern */
+	encx24j600_write_phy(priv, PHANA, PHANA_DEFAULT);
+
+	encx24j600_update_phcon1(priv);
+	encx24j600_check_link_status(priv);
+
+	macon2 = MACON2_RSV1 | TXCRCEN | PADCFG0 | PADCFG2 | MACON2_DEFER;
+	if ((priv->autoneg == AUTONEG_DISABLE) && priv->full_duplex)
+		macon2 |= FULDPX;
+
+	encx24j600_set_bits(priv, MACON2, macon2);
+
+	priv->rxfilter = RXFILTER_NORMAL;
+	encx24j600_set_rxfilter_mode(priv);
+
+	/* Program the Maximum frame length */
+	encx24j600_write_reg(priv, MAMXFL, MAX_FRAMELEN);
+
+	/* Init Tx pointers */
+	encx24j600_hw_init_tx(priv);
+
+	/* Init Rx pointers */
+	encx24j600_hw_init_rx(priv);
+
+	if (netif_msg_hw(priv))
+		encx24j600_dump_config(priv, "Hw is initialized");
+
+err_out:
+	return ret;
+}
+
+static void encx24j600_hw_enable(struct encx24j600_priv *priv)
+{
+	/* Clear the interrupt flags in case was set */
+	encx24j600_clr_bits(priv, EIR, (PCFULIF | RXABTIF | TXABTIF | TXIF |
+					PKTIF | LINKIF));
+
+	/* Enable the interrupts */
+	encx24j600_write_reg(priv, EIE, (PCFULIE | RXABTIE | TXABTIE | TXIE |
+					 PKTIE | LINKIE | INTIE));
+
+	/* Enable RX */
+	encx24j600_cmd(priv, ENABLERX);
+
+	priv->hw_enabled = true;
+}
+
+static void encx24j600_hw_disable(struct encx24j600_priv *priv)
+{
+	/* Disable all interrupts */
+	encx24j600_write_reg(priv, EIE, 0);
+
+	/* Disable RX */
+	encx24j600_cmd(priv, DISABLERX);
+
+	priv->hw_enabled = false;
+}
+
+static int encx24j600_setlink(struct net_device *dev, u8 autoneg, u16 speed,
+			      u8 duplex)
+{
+	struct encx24j600_priv *priv = netdev_priv(dev);
+	int ret = 0;
+
+	if (!priv->hw_enabled) {
+		/* link is in low power mode now; duplex setting
+		 * will take effect on next encx24j600_hw_init()
+		 */
+		if (speed == SPEED_10 || speed == SPEED_100) {
+			priv->autoneg = (autoneg == AUTONEG_ENABLE);
+			priv->full_duplex = (duplex == DUPLEX_FULL);
+			priv->speed = (speed == SPEED_100);
+		} else {
+			netif_warn(priv, link, dev, "unsupported link speed setting\n");
+			/*speeds other than SPEED_10 and SPEED_100 */
+			/*are not supported by chip */
+			ret = -EOPNOTSUPP;
+		}
+	} else {
+		netif_warn(priv, link, dev, "Warning: hw must be disabled to set link mode\n");
+		ret = -EBUSY;
+	}
+	return ret;
+}
+
+static void encx24j600_hw_get_macaddr(struct encx24j600_priv *priv,
+				      unsigned char *ethaddr)
+{
+	unsigned short val;
+
+	val = encx24j600_read_reg(priv, MAADR1);
+
+	ethaddr[0] = val & 0x00ff;
+	ethaddr[1] = (val & 0xff00) >> 8;
+
+	val = encx24j600_read_reg(priv, MAADR2);
+
+	ethaddr[2] = val & 0x00ffU;
+	ethaddr[3] = (val & 0xff00U) >> 8;
+
+	val = encx24j600_read_reg(priv, MAADR3);
+
+	ethaddr[4] = val & 0x00ffU;
+	ethaddr[5] = (val & 0xff00U) >> 8;
+}
+
+/* Program the hardware MAC address from dev->dev_addr.*/
+static int encx24j600_set_hw_macaddr(struct net_device *dev)
+{
+	struct encx24j600_priv *priv = netdev_priv(dev);
+
+	if (priv->hw_enabled) {
+		netif_info(priv, drv, dev, "Hardware must be disabled to set Mac address\n");
+		return -EBUSY;
+	}
+
+	mutex_lock(&priv->lock);
+
+	netif_info(priv, drv, dev, "%s: Setting MAC address to %pM\n",
+		   dev->name, dev->dev_addr);
+
+	encx24j600_write_reg(priv, MAADR3, (dev->dev_addr[4] |
+			     dev->dev_addr[5] << 8));
+	encx24j600_write_reg(priv, MAADR2, (dev->dev_addr[2] |
+			     dev->dev_addr[3] << 8));
+	encx24j600_write_reg(priv, MAADR1, (dev->dev_addr[0] |
+			     dev->dev_addr[1] << 8));
+
+	mutex_unlock(&priv->lock);
+
+	return 0;
+}
+
+/* Store the new hardware address in dev->dev_addr, and update the MAC.*/
+static int encx24j600_set_mac_address(struct net_device *dev, void *addr)
+{
+	struct sockaddr *address = addr;
+
+	if (netif_running(dev))
+		return -EBUSY;
+	if (!is_valid_ether_addr(address->sa_data))
+		return -EADDRNOTAVAIL;
+
+	memcpy(dev->dev_addr, address->sa_data, dev->addr_len);
+	return encx24j600_set_hw_macaddr(dev);
+}
+
+static int encx24j600_open(struct net_device *dev)
+{
+	struct encx24j600_priv *priv = netdev_priv(dev);
+
+	int ret = request_threaded_irq(priv->ctx.spi->irq, NULL, encx24j600_isr,
+				       IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
+				       DRV_NAME, priv);
+	if (unlikely(ret < 0)) {
+		netdev_err(dev, "request irq %d failed (ret = %d)\n",
+			   priv->ctx.spi->irq, ret);
+		return ret;
+	}
+
+	encx24j600_hw_disable(priv);
+	encx24j600_hw_init(priv);
+	encx24j600_hw_enable(priv);
+	netif_start_queue(dev);
+
+	return 0;
+}
+
+static int encx24j600_stop(struct net_device *dev)
+{
+	struct encx24j600_priv *priv = netdev_priv(dev);
+
+	netif_stop_queue(dev);
+	free_irq(priv->ctx.spi->irq, priv);
+	return 0;
+}
+
+static void encx24j600_setrx_proc(struct kthread_work *ws)
+{
+	struct encx24j600_priv *priv =
+			container_of(ws, struct encx24j600_priv, setrx_work);
+
+	mutex_lock(&priv->lock);
+	encx24j600_set_rxfilter_mode(priv);
+	mutex_unlock(&priv->lock);
+}
+
+static void encx24j600_set_multicast_list(struct net_device *dev)
+{
+	struct encx24j600_priv *priv = netdev_priv(dev);
+	int oldfilter = priv->rxfilter;
+
+	if (dev->flags & IFF_PROMISC) {
+		netif_dbg(priv, link, dev, "promiscuous mode\n");
+		priv->rxfilter = RXFILTER_PROMISC;
+	} else if ((dev->flags & IFF_ALLMULTI) || !netdev_mc_empty(dev)) {
+		netif_dbg(priv, link, dev, "%smulticast mode\n",
+			  (dev->flags & IFF_ALLMULTI) ? "all-" : "");
+		priv->rxfilter = RXFILTER_MULTI;
+	} else {
+		netif_dbg(priv, link, dev, "normal mode\n");
+		priv->rxfilter = RXFILTER_NORMAL;
+	}
+
+	if (oldfilter != priv->rxfilter)
+		queue_kthread_work(&priv->kworker, &priv->setrx_work);
+}
+
+static void encx24j600_hw_tx(struct encx24j600_priv *priv)
+{
+	struct net_device *dev = priv->ndev;
+	netif_info(priv, tx_queued, dev, "TX Packet Len:%d\n",
+		   priv->tx_skb->len);
+
+	if (netif_msg_pktdata(priv))
+		dump_packet("TX", priv->tx_skb->len, priv->tx_skb->data);
+
+	if (encx24j600_read_reg(priv, EIR) & TXABTIF)
+		/* Last transmition aborted due to error. Reset TX interface */
+		encx24j600_reset_hw_tx(priv);
+
+	/* Clear the TXIF flag if were previously set */
+	encx24j600_clr_bits(priv, EIR, TXIF);
+
+	/* Set the data pointer to the TX buffer address in the SRAM */
+	encx24j600_write_reg(priv, EGPWRPT, ENC_TX_BUF_START);
+
+	/* Copy the packet into the SRAM */
+	encx24j600_raw_write(priv, WGPDATA, (u8 *)priv->tx_skb->data,
+			     priv->tx_skb->len);
+
+	/* Program the Tx buffer start pointer */
+	encx24j600_write_reg(priv, ETXST, ENC_TX_BUF_START);
+
+	/* Program the packet length */
+	encx24j600_write_reg(priv, ETXLEN, priv->tx_skb->len);
+
+	/* Start the transmission */
+	encx24j600_cmd(priv, SETTXRTS);
+}
+
+static void encx24j600_tx_proc(struct kthread_work *ws)
+{
+	struct encx24j600_priv *priv =
+			container_of(ws, struct encx24j600_priv, tx_work);
+
+	mutex_lock(&priv->lock);
+	encx24j600_hw_tx(priv);
+	mutex_unlock(&priv->lock);
+}
+
+static netdev_tx_t encx24j600_tx(struct sk_buff *skb, struct net_device *dev)
+{
+	struct encx24j600_priv *priv = netdev_priv(dev);
+
+	netif_stop_queue(dev);
+
+	/* save the timestamp */
+	dev->trans_start = jiffies;
+
+	/* Remember the skb for deferred processing */
+	priv->tx_skb = skb;
+
+	queue_kthread_work(&priv->kworker, &priv->tx_work);
+
+	return NETDEV_TX_OK;
+}
+
+/* Deal with a transmit timeout */
+static void encx24j600_tx_timeout(struct net_device *dev)
+{
+	struct encx24j600_priv *priv = netdev_priv(dev);
+
+	netif_err(priv, tx_err, dev, "TX timeout at %ld, latency %ld\n",
+		  jiffies, jiffies - dev->trans_start);
+
+	dev->stats.tx_errors++;
+	netif_wake_queue(dev);
+	return;
+}
+
+static int encx24j600_get_regs_len(struct net_device *dev)
+{
+	return SFR_REG_COUNT;
+}
+
+static void encx24j600_get_regs(struct net_device *dev,
+				struct ethtool_regs *regs, void *p)
+{
+	struct encx24j600_priv *priv = netdev_priv(dev);
+	u16 *buff = p;
+	u8 reg;
+
+	regs->version = 1;
+	mutex_lock(&priv->lock);
+	for (reg = 0; reg < SFR_REG_COUNT; reg += 2) {
+		unsigned int val = 0;
+		/* ignore errors for unreadable registers */
+		regmap_read(priv->ctx.regmap, reg, &val);
+		buff[reg] = val & 0xffff;
+	}
+	mutex_unlock(&priv->lock);
+}
+
+static void encx24j600_get_drvinfo(struct net_device *dev,
+				   struct ethtool_drvinfo *info)
+{
+	strlcpy(info->driver, DRV_NAME, sizeof(info->driver));
+	strlcpy(info->version, DRV_VERSION, sizeof(info->version));
+	strlcpy(info->bus_info, dev_name(dev->dev.parent),
+		sizeof(info->bus_info));
+}
+
+static int encx24j600_get_settings(struct net_device *dev,
+				   struct ethtool_cmd *cmd)
+{
+	struct encx24j600_priv *priv = netdev_priv(dev);
+
+	cmd->transceiver = XCVR_INTERNAL;
+	cmd->supported = SUPPORTED_10baseT_Half | SUPPORTED_10baseT_Full |
+			 SUPPORTED_100baseT_Half | SUPPORTED_100baseT_Full |
+			 SUPPORTED_Autoneg | SUPPORTED_TP;
+
+	ethtool_cmd_speed_set(cmd, priv->speed);
+	cmd->duplex = priv->full_duplex ? DUPLEX_FULL : DUPLEX_HALF;
+	cmd->port = PORT_TP;
+	cmd->autoneg = priv->autoneg ? AUTONEG_ENABLE : AUTONEG_DISABLE;
+
+	return 0;
+}
+
+static int encx24j600_set_settings(struct net_device *dev,
+				   struct ethtool_cmd *cmd)
+{
+	return encx24j600_setlink(dev, cmd->autoneg,
+				  ethtool_cmd_speed(cmd), cmd->duplex);
+}
+
+static u32 encx24j600_get_msglevel(struct net_device *dev)
+{
+	struct encx24j600_priv *priv = netdev_priv(dev);
+	return priv->msg_enable;
+}
+
+static void encx24j600_set_msglevel(struct net_device *dev, u32 val)
+{
+	struct encx24j600_priv *priv = netdev_priv(dev);
+	priv->msg_enable = val;
+}
+
+static const struct ethtool_ops encx24j600_ethtool_ops = {
+	.get_settings = encx24j600_get_settings,
+	.set_settings = encx24j600_set_settings,
+	.get_drvinfo = encx24j600_get_drvinfo,
+	.get_msglevel = encx24j600_get_msglevel,
+	.set_msglevel = encx24j600_set_msglevel,
+	.get_regs_len = encx24j600_get_regs_len,
+	.get_regs = encx24j600_get_regs,
+};
+
+static const struct net_device_ops encx24j600_netdev_ops = {
+	.ndo_open = encx24j600_open,
+	.ndo_stop = encx24j600_stop,
+	.ndo_start_xmit = encx24j600_tx,
+	.ndo_set_rx_mode = encx24j600_set_multicast_list,
+	.ndo_set_mac_address = encx24j600_set_mac_address,
+	.ndo_tx_timeout = encx24j600_tx_timeout,
+	.ndo_validate_addr = eth_validate_addr,
+};
+
+static int encx24j600_spi_probe(struct spi_device *spi)
+{
+	int ret;
+
+	struct net_device *ndev;
+	struct encx24j600_priv *priv;
+
+	ndev = alloc_etherdev(sizeof(struct encx24j600_priv));
+
+	if (!ndev) {
+		ret = -ENOMEM;
+		goto error_out;
+	}
+
+	priv = netdev_priv(ndev);
+	spi_set_drvdata(spi, priv);
+	dev_set_drvdata(&spi->dev, priv);
+	SET_NETDEV_DEV(ndev, &spi->dev);
+
+	priv->msg_enable = netif_msg_init(debug, DEFAULT_MSG_ENABLE);
+	priv->ndev = ndev;
+
+	/* Default configuration PHY configuration */
+	priv->full_duplex = true;
+	priv->autoneg = AUTONEG_ENABLE;
+	priv->speed = SPEED_100;
+
+	priv->ctx.spi = spi;
+	devm_regmap_init_encx24j600(&spi->dev, &priv->ctx);
+	ndev->irq = spi->irq;
+	ndev->netdev_ops = &encx24j600_netdev_ops;
+
+	mutex_init(&priv->lock);
+
+	/* Reset device and check if it is connected */
+	if (encx24j600_hw_reset(priv)) {
+		netif_err(priv, probe, ndev,
+			  DRV_NAME ": Chip is not detected\n");
+		ret = -EIO;
+		goto out_free;
+	}
+
+	/* Initialize the device HW to the consistent state */
+	if (encx24j600_hw_init(priv)) {
+		netif_err(priv, probe, ndev,
+			  DRV_NAME ": HW initialization error\n");
+		ret = -EIO;
+		goto out_free;
+	}
+
+	init_kthread_worker(&priv->kworker);
+	init_kthread_work(&priv->tx_work, encx24j600_tx_proc);
+	init_kthread_work(&priv->setrx_work, encx24j600_setrx_proc);
+
+	priv->kworker_task = kthread_run(kthread_worker_fn, &priv->kworker,
+					 "encx24j600");
+
+	if (IS_ERR(priv->kworker_task)) {
+		ret = PTR_ERR(priv->kworker_task);
+		goto out_free;
+	}
+
+	/* Get the MAC address from the chip */
+	encx24j600_hw_get_macaddr(priv, ndev->dev_addr);
+
+	ndev->ethtool_ops = &encx24j600_ethtool_ops;
+
+	ret = register_netdev(ndev);
+	if (unlikely(ret)) {
+		netif_err(priv, probe, ndev, "Error %d initializing card encx24j600 card\n",
+			  ret);
+		goto out_free;
+	}
+
+	netif_info(priv, drv, priv->ndev, "MAC address %pM\n", ndev->dev_addr);
+
+	return ret;
+
+out_free:
+	free_netdev(ndev);
+
+error_out:
+	return ret;
+}
+
+static int encx24j600_spi_remove(struct spi_device *spi)
+{
+	struct encx24j600_priv *priv = dev_get_drvdata(&spi->dev);
+
+	unregister_netdev(priv->ndev);
+
+	free_netdev(priv->ndev);
+
+	return 0;
+}
+
+static const struct spi_device_id encx24j600_spi_id_table = {
+	.name = "encx24j600"
+};
+
+static struct spi_driver encx24j600_spi_net_driver = {
+	.driver = {
+		.name	= DRV_NAME,
+		.owner	= THIS_MODULE,
+		.bus	= &spi_bus_type,
+	},
+	.probe		= encx24j600_spi_probe,
+	.remove		= encx24j600_spi_remove,
+	.id_table	= &encx24j600_spi_id_table,
+};
+
+static int __init encx24j600_init(void)
+{
+	return spi_register_driver(&encx24j600_spi_net_driver);
+}
+module_init(encx24j600_init);
+
+static void encx24j600_exit(void)
+{
+	spi_unregister_driver(&encx24j600_spi_net_driver);
+}
+module_exit(encx24j600_exit);
+
+MODULE_DESCRIPTION(DRV_NAME " ethernet driver");
+MODULE_AUTHOR("Jon Ringle <jringle@gridpoint.com>");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("spi:" DRV_NAME);