[smscusb] Abstract out common SMSC USB device functionality

The smsc75xx and smsc95xx drivers include a substantial amount of
identical functionality, varying only in the base address of register
sets.  Abstract out this common functionality to allow code to be
shared between the drivers.

Signed-off-by: Michael Brown <mcb30@ipxe.org>

2 files changed, 825 insertions, 0 deletions

diff --git a/src/drivers/net/smscusb.c b/src/drivers/net/smscusb.c
new file mode 100644
index 00000000..d4f3af03
--- /dev/null
+++ b/src/drivers/net/smscusb.c
@@ -0,0 +1,523 @@
+/*
+ * Copyright (C) 2017 Michael Brown <mbrown@fensystems.co.uk>.
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ *
+ * You can also choose to distribute this program under the terms of
+ * the Unmodified Binary Distribution Licence (as given in the file
+ * COPYING.UBDL), provided that you have satisfied its requirements.
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
+
+#include <string.h>
+#include <errno.h>
+#include <unistd.h>
+#include <ipxe/usb.h>
+#include <ipxe/usbnet.h>
+#include <ipxe/ethernet.h>
+#include <ipxe/profile.h>
+#include "smscusb.h"
+
+/** @file
+ *
+ * SMSC USB Ethernet drivers
+ *
+ */
+
+/** Interrupt completion profiler */
+static struct profiler smscusb_intr_profiler __profiler =
+	{ .name = "smscusb.intr" };
+
+/******************************************************************************
+ *
+ * EEPROM access
+ *
+ ******************************************************************************
+ */
+
+/**
+ * Wait for EEPROM to become idle
+ *
+ * @v smscusb		SMSC USB device
+ * @v e2p_base		E2P register base
+ * @ret rc		Return status code
+ */
+static int smscusb_eeprom_wait ( struct smscusb_device *smscusb,
+				 unsigned int e2p_base ) {
+	uint32_t e2p_cmd;
+	unsigned int i;
+	int rc;
+
+	/* Wait for EPC_BSY to become clear */
+	for ( i = 0 ; i < SMSCUSB_EEPROM_MAX_WAIT_MS ; i++ ) {
+
+		/* Read E2P_CMD and check EPC_BSY */
+		if ( ( rc = smscusb_readl ( smscusb,
+					    ( e2p_base + SMSCUSB_E2P_CMD ),
+					    &e2p_cmd ) ) != 0 )
+			return rc;
+		if ( ! ( e2p_cmd & SMSCUSB_E2P_CMD_EPC_BSY ) )
+			return 0;
+
+		/* Delay */
+		mdelay ( 1 );
+	}
+
+	DBGC ( smscusb, "SMSCUSB %p timed out waiting for EEPROM\n",
+	       smscusb );
+	return -ETIMEDOUT;
+}
+
+/**
+ * Read byte from EEPROM
+ *
+ * @v smscusb		SMSC USB device
+ * @v e2p_base		E2P register base
+ * @v address		EEPROM address
+ * @ret byte		Byte read, or negative error
+ */
+static int smscusb_eeprom_read_byte ( struct smscusb_device *smscusb,
+				      unsigned int e2p_base,
+				      unsigned int address ) {
+	uint32_t e2p_cmd;
+	uint32_t e2p_data;
+	int rc;
+
+	/* Wait for EEPROM to become idle */
+	if ( ( rc = smscusb_eeprom_wait ( smscusb, e2p_base ) ) != 0 )
+		return rc;
+
+	/* Initiate read command */
+	e2p_cmd = ( SMSCUSB_E2P_CMD_EPC_BSY | SMSCUSB_E2P_CMD_EPC_CMD_READ |
+		    SMSCUSB_E2P_CMD_EPC_ADDR ( address ) );
+	if ( ( rc = smscusb_writel ( smscusb, ( e2p_base + SMSCUSB_E2P_CMD ),
+				     e2p_cmd ) ) != 0 )
+		return rc;
+
+	/* Wait for command to complete */
+	if ( ( rc = smscusb_eeprom_wait ( smscusb, e2p_base ) ) != 0 )
+		return rc;
+
+	/* Read EEPROM data */
+	if ( ( rc = smscusb_readl ( smscusb, ( e2p_base + SMSCUSB_E2P_DATA ),
+				    &e2p_data ) ) != 0 )
+		return rc;
+
+	return SMSCUSB_E2P_DATA_GET ( e2p_data );
+}
+
+/**
+ * Read data from EEPROM
+ *
+ * @v smscusb		SMSC USB device
+ * @v e2p_base		E2P register base
+ * @v address		EEPROM address
+ * @v data		Data buffer
+ * @v len		Length of data
+ * @ret rc		Return status code
+ */
+static int smscusb_eeprom_read ( struct smscusb_device *smscusb,
+				 unsigned int e2p_base, unsigned int address,
+				 void *data, size_t len ) {
+	uint8_t *bytes;
+	int byte;
+
+	/* Read bytes */
+	for ( bytes = data ; len-- ; address++, bytes++ ) {
+		byte = smscusb_eeprom_read_byte ( smscusb, e2p_base, address );
+		if ( byte < 0 )
+			return byte;
+		*bytes = byte;
+	}
+
+	return 0;
+}
+
+/**
+ * Fetch MAC address from EEPROM
+ *
+ * @v smscusb		SMSC USB device
+ * @v e2p_base		E2P register base
+ * @ret rc		Return status code
+ */
+int smscusb_eeprom_fetch_mac ( struct smscusb_device *smscusb,
+			       unsigned int e2p_base ) {
+	struct net_device *netdev = smscusb->netdev;
+	int rc;
+
+	/* Read MAC address from EEPROM */
+	if ( ( rc = smscusb_eeprom_read ( smscusb, e2p_base, SMSCUSB_EEPROM_MAC,
+					  netdev->hw_addr, ETH_ALEN ) ) != 0 )
+		return rc;
+
+	/* Check that EEPROM is physically present */
+	if ( ! is_valid_ether_addr ( netdev->hw_addr ) ) {
+		DBGC ( smscusb, "SMSCUSB %p has no EEPROM (%s)\n",
+		       smscusb, eth_ntoa ( netdev->hw_addr ) );
+		return -ENODEV;
+	}
+
+	DBGC ( smscusb, "SMSCUSB %p using EEPROM MAC %s\n",
+	       smscusb, eth_ntoa ( netdev->hw_addr ) );
+	return 0;
+}
+
+/******************************************************************************
+ *
+ * MII access
+ *
+ ******************************************************************************
+ */
+
+/**
+ * Wait for MII to become idle
+ *
+ * @v smscusb		SMSC USB device
+ * @ret rc		Return status code
+ */
+static int smscusb_mii_wait ( struct smscusb_device *smscusb ) {
+	unsigned int base = smscusb->mii_base;
+	uint32_t mii_access;
+	unsigned int i;
+	int rc;
+
+	/* Wait for MIIBZY to become clear */
+	for ( i = 0 ; i < SMSCUSB_MII_MAX_WAIT_MS ; i++ ) {
+
+		/* Read MII_ACCESS and check MIIBZY */
+		if ( ( rc = smscusb_readl ( smscusb,
+					    ( base + SMSCUSB_MII_ACCESS ),
+					    &mii_access ) ) != 0 )
+			return rc;
+		if ( ! ( mii_access & SMSCUSB_MII_ACCESS_MIIBZY ) )
+			return 0;
+
+		/* Delay */
+		mdelay ( 1 );
+	}
+
+	DBGC ( smscusb, "SMSCUSB %p timed out waiting for MII\n",
+	       smscusb );
+	return -ETIMEDOUT;
+}
+
+/**
+ * Read from MII register
+ *
+ * @v mii		MII interface
+ * @v reg		Register address
+ * @ret value		Data read, or negative error
+ */
+static int smscusb_mii_read ( struct mii_interface *mii, unsigned int reg ) {
+	struct smscusb_device *smscusb =
+		container_of ( mii, struct smscusb_device, mii );
+	unsigned int base = smscusb->mii_base;
+	uint32_t mii_access;
+	uint32_t mii_data;
+	int rc;
+
+	/* Wait for MII to become idle */
+	if ( ( rc = smscusb_mii_wait ( smscusb ) ) != 0 )
+		return rc;
+
+	/* Initiate read command */
+	mii_access = ( SMSCUSB_MII_ACCESS_PHY_ADDRESS |
+		       SMSCUSB_MII_ACCESS_MIIRINDA ( reg ) |
+		       SMSCUSB_MII_ACCESS_MIIBZY );
+	if ( ( rc = smscusb_writel ( smscusb, ( base + SMSCUSB_MII_ACCESS ),
+				     mii_access ) ) != 0 )
+		return rc;
+
+	/* Wait for command to complete */
+	if ( ( rc = smscusb_mii_wait ( smscusb ) ) != 0 )
+		return rc;
+
+	/* Read MII data */
+	if ( ( rc = smscusb_readl ( smscusb, ( base + SMSCUSB_MII_DATA ),
+				    &mii_data ) ) != 0 )
+		return rc;
+
+	return SMSCUSB_MII_DATA_GET ( mii_data );
+}
+
+/**
+ * Write to MII register
+ *
+ * @v mii		MII interface
+ * @v reg		Register address
+ * @v data		Data to write
+ * @ret rc		Return status code
+ */
+static int smscusb_mii_write ( struct mii_interface *mii, unsigned int reg,
+			       unsigned int data ) {
+	struct smscusb_device *smscusb =
+		container_of ( mii, struct smscusb_device, mii );
+	unsigned int base = smscusb->mii_base;
+	uint32_t mii_access;
+	uint32_t mii_data;
+	int rc;
+
+	/* Wait for MII to become idle */
+	if ( ( rc = smscusb_mii_wait ( smscusb ) ) != 0 )
+		return rc;
+
+	/* Write MII data */
+	mii_data = SMSCUSB_MII_DATA_SET ( data );
+	if ( ( rc = smscusb_writel ( smscusb, ( base + SMSCUSB_MII_DATA ),
+				     mii_data ) ) != 0 )
+		return rc;
+
+	/* Initiate write command */
+	mii_access = ( SMSCUSB_MII_ACCESS_PHY_ADDRESS |
+		       SMSCUSB_MII_ACCESS_MIIRINDA ( reg ) |
+		       SMSCUSB_MII_ACCESS_MIIWNR |
+		       SMSCUSB_MII_ACCESS_MIIBZY );
+	if ( ( rc = smscusb_writel ( smscusb, ( base + SMSCUSB_MII_ACCESS ),
+				     mii_access ) ) != 0 )
+		return rc;
+
+	/* Wait for command to complete */
+	if ( ( rc = smscusb_mii_wait ( smscusb ) ) != 0 )
+		return rc;
+
+	return 0;
+}
+
+/** MII operations */
+struct mii_operations smscusb_mii_operations = {
+	.read = smscusb_mii_read,
+	.write = smscusb_mii_write,
+};
+
+/**
+ * Check link status
+ *
+ * @v smscusb		SMSC USB device
+ * @ret rc		Return status code
+ */
+int smscusb_mii_check_link ( struct smscusb_device *smscusb ) {
+	struct net_device *netdev = smscusb->netdev;
+	int intr;
+	int rc;
+
+	/* Read PHY interrupt source */
+	intr = mii_read ( &smscusb->mii, SMSCUSB_MII_PHY_INTR_SOURCE );
+	if ( intr < 0 ) {
+		rc = intr;
+		DBGC ( smscusb, "SMSCUSB %p could not get PHY interrupt "
+		       "source: %s\n", smscusb, strerror ( rc ) );
+		return rc;
+	}
+
+	/* Acknowledge PHY interrupt */
+	if ( ( rc = mii_write ( &smscusb->mii, SMSCUSB_MII_PHY_INTR_SOURCE,
+				intr ) ) != 0 ) {
+		DBGC ( smscusb, "SMSCUSB %p could not acknowledge PHY "
+		       "interrupt: %s\n", smscusb, strerror ( rc ) );
+		return rc;
+	}
+
+	/* Check link status */
+	if ( ( rc = mii_check_link ( &smscusb->mii, netdev ) ) != 0 ) {
+		DBGC ( smscusb, "SMSCUSB %p could not check link: %s\n",
+		       smscusb, strerror ( rc ) );
+		return rc;
+	}
+
+	DBGC ( smscusb, "SMSCUSB %p link %s (intr %#04x)\n",
+	       smscusb, ( netdev_link_ok ( netdev ) ? "up" : "down" ), intr );
+	return 0;
+}
+
+/**
+ * Enable PHY interrupts and update link status
+ *
+ * @v smscusb		SMSC USB device
+ * @ret rc		Return status code
+ */
+int smscusb_mii_open ( struct smscusb_device *smscusb ) {
+	int rc;
+
+	/* Enable PHY interrupts */
+	if ( ( rc = mii_write ( &smscusb->mii, SMSCUSB_MII_PHY_INTR_MASK,
+				( SMSCUSB_PHY_INTR_ANEG_DONE |
+				  SMSCUSB_PHY_INTR_LINK_DOWN ) ) ) != 0 ) {
+		DBGC ( smscusb, "SMSCUSB %p could not set PHY interrupt "
+		       "mask: %s\n", smscusb, strerror ( rc ) );
+		return rc;
+	}
+
+	/* Update link status */
+	smscusb_mii_check_link ( smscusb );
+
+	return 0;
+}
+
+/******************************************************************************
+ *
+ * Receive filtering
+ *
+ ******************************************************************************
+ */
+
+/**
+ * Set receive address
+ *
+ * @v smscusb		SMSC USB device
+ * @v addr_base		Receive address register base
+ * @ret rc		Return status code
+ */
+int smscusb_set_address ( struct smscusb_device *smscusb,
+			  unsigned int addr_base ) {
+	struct net_device *netdev = smscusb->netdev;
+	union smscusb_mac mac;
+	int rc;
+
+	/* Copy MAC address */
+	memset ( &mac, 0, sizeof ( mac ) );
+	memcpy ( mac.raw, netdev->ll_addr, ETH_ALEN );
+
+	/* Write MAC address high register */
+	if ( ( rc = smscusb_raw_writel ( smscusb,
+					 ( addr_base + SMSCUSB_RX_ADDRH ),
+					 mac.addr.h ) ) != 0 )
+		return rc;
+
+	/* Write MAC address low register */
+	if ( ( rc = smscusb_raw_writel ( smscusb,
+					 ( addr_base + SMSCUSB_RX_ADDRL ),
+					 mac.addr.l ) ) != 0 )
+		return rc;
+
+	return 0;
+}
+
+/**
+ * Set receive filter
+ *
+ * @v smscusb		SMSC USB device
+ * @v filt_base		Receive filter register base
+ * @ret rc		Return status code
+ */
+int smscusb_set_filter ( struct smscusb_device *smscusb,
+			 unsigned int filt_base ) {
+	struct net_device *netdev = smscusb->netdev;
+	union smscusb_mac mac;
+	int rc;
+
+	/* Copy MAC address */
+	memset ( &mac, 0, sizeof ( mac ) );
+	memcpy ( mac.raw, netdev->ll_addr, ETH_ALEN );
+	mac.addr.h |= cpu_to_le32 ( SMSCUSB_ADDR_FILTH_VALID );
+
+	/* Write MAC address perfect filter high register */
+	if ( ( rc = smscusb_raw_writel ( smscusb,
+					 ( filt_base + SMSCUSB_ADDR_FILTH(0) ),
+					 mac.addr.h ) ) != 0 )
+		return rc;
+
+	/* Write MAC address perfect filter low register */
+	if ( ( rc = smscusb_raw_writel ( smscusb,
+					 ( filt_base + SMSCUSB_ADDR_FILTL(0) ),
+					 mac.addr.l ) ) != 0 )
+		return rc;
+
+	return 0;
+}
+
+/******************************************************************************
+ *
+ * Endpoint operations
+ *
+ ******************************************************************************
+ */
+
+/**
+ * Complete interrupt transfer
+ *
+ * @v ep		USB endpoint
+ * @v iobuf		I/O buffer
+ * @v rc		Completion status code
+ */
+static void smscusb_intr_complete ( struct usb_endpoint *ep,
+				    struct io_buffer *iobuf, int rc ) {
+	struct smscusb_device *smscusb =
+		container_of ( ep, struct smscusb_device, usbnet.intr );
+	struct net_device *netdev = smscusb->netdev;
+	struct smscusb_interrupt *intr;
+
+	/* Profile completions */
+	profile_start ( &smscusb_intr_profiler );
+
+	/* Ignore packets cancelled when the endpoint closes */
+	if ( ! ep->open )
+		goto done;
+
+	/* Record USB errors against the network device */
+	if ( rc != 0 ) {
+		DBGC ( smscusb, "SMSCUSB %p interrupt failed: %s\n",
+		       smscusb, strerror ( rc ) );
+		DBGC_HDA ( smscusb, 0, iobuf->data, iob_len ( iobuf ) );
+		netdev_rx_err ( netdev, NULL, rc );
+		goto done;
+	}
+
+	/* Extract interrupt data */
+	if ( iob_len ( iobuf ) != sizeof ( *intr ) ) {
+		DBGC ( smscusb, "SMSCUSB %p malformed interrupt\n",
+		       smscusb );
+		DBGC_HDA ( smscusb, 0, iobuf->data, iob_len ( iobuf ) );
+		netdev_rx_err ( netdev, NULL, rc );
+		goto done;
+	}
+	intr = iobuf->data;
+
+	/* Record interrupt status */
+	smscusb->int_sts = le32_to_cpu ( intr->int_sts );
+	profile_stop ( &smscusb_intr_profiler );
+
+ done:
+	/* Free I/O buffer */
+	free_iob ( iobuf );
+}
+
+/** Interrupt endpoint operations */
+struct usb_endpoint_driver_operations smscusb_intr_operations = {
+	.complete = smscusb_intr_complete,
+};
+
+/**
+ * Complete bulk OUT transfer
+ *
+ * @v ep		USB endpoint
+ * @v iobuf		I/O buffer
+ * @v rc		Completion status code
+ */
+static void smscusb_out_complete ( struct usb_endpoint *ep,
+				   struct io_buffer *iobuf, int rc ) {
+	struct smscusb_device *smscusb =
+		container_of ( ep, struct smscusb_device, usbnet.out );
+	struct net_device *netdev = smscusb->netdev;
+
+	/* Report TX completion */
+	netdev_tx_complete_err ( netdev, iobuf, rc );
+}
+
+/** Bulk OUT endpoint operations */
+struct usb_endpoint_driver_operations smscusb_out_operations = {
+	.complete = smscusb_out_complete,
+};
diff --git a/src/drivers/net/smscusb.h b/src/drivers/net/smscusb.h
new file mode 100644
index 00000000..15233818
--- /dev/null
+++ b/src/drivers/net/smscusb.h
@@ -0,0 +1,302 @@
+#ifndef _SMSCUSB_H
+#define _SMSCUSB_H
+
+/** @file
+ *
+ * SMSC USB Ethernet drivers
+ *
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
+
+#include <stdint.h>
+#include <string.h>
+#include <byteswap.h>
+#include <ipxe/usb.h>
+#include <ipxe/usbnet.h>
+#include <ipxe/netdevice.h>
+#include <ipxe/mii.h>
+#include <ipxe/if_ether.h>
+
+/** Register write command */
+#define SMSCUSB_REGISTER_WRITE					\
+	( USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE |	\
+	  USB_REQUEST_TYPE ( 0xa0 ) )
+
+/** Register read command */
+#define SMSCUSB_REGISTER_READ					\
+	( USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE |	\
+	  USB_REQUEST_TYPE ( 0xa1 ) )
+
+/** Get statistics command */
+#define SMSCUSB_GET_STATISTICS					\
+	( USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE |	\
+	  USB_REQUEST_TYPE ( 0xa2 ) )
+
+/** EEPROM command register offset */
+#define SMSCUSB_E2P_CMD 0x000
+#define SMSCUSB_E2P_CMD_EPC_BSY		0x80000000UL	/**< EPC busy */
+#define SMSCUSB_E2P_CMD_EPC_CMD_READ	0x00000000UL	/**< READ command */
+#define SMSCUSB_E2P_CMD_EPC_ADDR(addr) ( (addr) << 0 )	/**< EPC address */
+
+/** EEPROM data register offset */
+#define SMSCUSB_E2P_DATA 0x004
+#define SMSCUSB_E2P_DATA_GET(e2p_data) \
+	( ( (e2p_data) >> 0 ) & 0xff )			/**< EEPROM data */
+
+/** MAC address EEPROM address */
+#define SMSCUSB_EEPROM_MAC 0x01
+
+/** Maximum time to wait for EEPROM (in milliseconds) */
+#define SMSCUSB_EEPROM_MAX_WAIT_MS 100
+
+/** MII access register offset */
+#define SMSCUSB_MII_ACCESS 0x000
+#define SMSCUSB_MII_ACCESS_PHY_ADDRESS	0x00000800UL	/**< PHY address */
+#define SMSCUSB_MII_ACCESS_MIIRINDA(addr) ( (addr) << 6 ) /**< MII register */
+#define SMSCUSB_MII_ACCESS_MIIWNR	0x00000002UL	/**< MII write */
+#define SMSCUSB_MII_ACCESS_MIIBZY	0x00000001UL	/**< MII busy */
+
+/** MII data register offset */
+#define SMSCUSB_MII_DATA 0x004
+#define SMSCUSB_MII_DATA_SET(data)	( (data) << 0 )	/**< Set data */
+#define SMSCUSB_MII_DATA_GET(mii_data) \
+	( ( (mii_data) >> 0 ) & 0xffff )		/**< Get data */
+
+/** PHY interrupt source MII register */
+#define SMSCUSB_MII_PHY_INTR_SOURCE 29
+
+/** PHY interrupt mask MII register */
+#define SMSCUSB_MII_PHY_INTR_MASK 30
+
+/** PHY interrupt: auto-negotiation complete */
+#define SMSCUSB_PHY_INTR_ANEG_DONE 0x0040
+
+/** PHY interrupt: link down */
+#define SMSCUSB_PHY_INTR_LINK_DOWN 0x0010
+
+/** Maximum time to wait for MII (in milliseconds) */
+#define SMSCUSB_MII_MAX_WAIT_MS 100
+
+/** MAC address */
+union smscusb_mac {
+	/** MAC receive address registers */
+	struct {
+		/** MAC receive address low register */
+		uint32_t l;
+		/** MAC receive address high register */
+		uint32_t h;
+	} __attribute__ (( packed )) addr;
+	/** Raw MAC address */
+	uint8_t raw[ETH_ALEN];
+};
+
+/** MAC receive address high register offset */
+#define SMSCUSB_RX_ADDRH 0x000
+
+/** MAC receive address low register offset */
+#define SMSCUSB_RX_ADDRL 0x004
+
+/** MAC address perfect filter N high register offset */
+#define SMSCUSB_ADDR_FILTH(n) ( 0x000 + ( 8 * (n) ) )
+#define SMSCUSB_ADDR_FILTH_VALID	0x80000000UL	/**< Address valid */
+
+/** MAC address perfect filter N low register offset */
+#define SMSCUSB_ADDR_FILTL(n) ( 0x004 + ( 8 * (n) ) )
+
+/** Interrupt packet format */
+struct smscusb_interrupt {
+	/** Current value of INT_STS register */
+	uint32_t int_sts;
+} __attribute__ (( packed ));
+
+/** An SMSC USB device */
+struct smscusb_device {
+	/** USB device */
+	struct usb_device *usb;
+	/** USB bus */
+	struct usb_bus *bus;
+	/** Network device */
+	struct net_device *netdev;
+	/** USB network device */
+	struct usbnet_device usbnet;
+	/** MII interface */
+	struct mii_interface mii;
+	/** MII register base */
+	uint16_t mii_base;
+	/** Interrupt status */
+	uint32_t int_sts;
+};
+
+/**
+ * Write register (without byte-swapping)
+ *
+ * @v smscusb		Smscusb device
+ * @v address		Register address
+ * @v value		Register value
+ * @ret rc		Return status code
+ */
+static int smscusb_raw_writel ( struct smscusb_device *smscusb,
+				unsigned int address, uint32_t value ) {
+	int rc;
+
+	/* Write register */
+	DBGCIO ( smscusb, "SMSCUSB %p [%03x] <= %08x\n",
+		 smscusb, address, le32_to_cpu ( value ) );
+	if ( ( rc = usb_control ( smscusb->usb, SMSCUSB_REGISTER_WRITE, 0,
+				  address, &value, sizeof ( value ) ) ) != 0 ) {
+		DBGC ( smscusb, "SMSCUSB %p could not write %03x: %s\n",
+		       smscusb, address, strerror ( rc ) );
+		return rc;
+	}
+
+	return 0;
+}
+
+/**
+ * Write register
+ *
+ * @v smscusb		SMSC USB device
+ * @v address		Register address
+ * @v value		Register value
+ * @ret rc		Return status code
+ */
+static inline __attribute__ (( always_inline )) int
+smscusb_writel ( struct smscusb_device *smscusb, unsigned int address,
+		 uint32_t value ) {
+	int rc;
+
+	/* Write register */
+	if ( ( rc = smscusb_raw_writel ( smscusb, address,
+					 cpu_to_le32 ( value ) ) ) != 0 )
+		return rc;
+
+	return 0;
+}
+
+/**
+ * Read register (without byte-swapping)
+ *
+ * @v smscusb		SMSC USB device
+ * @v address		Register address
+ * @ret value		Register value
+ * @ret rc		Return status code
+ */
+static int smscusb_raw_readl ( struct smscusb_device *smscusb,
+			       unsigned int address, uint32_t *value ) {
+	int rc;
+
+	/* Read register */
+	if ( ( rc = usb_control ( smscusb->usb, SMSCUSB_REGISTER_READ, 0,
+				  address, value, sizeof ( *value ) ) ) != 0 ) {
+		DBGC ( smscusb, "SMSCUSB %p could not read %03x: %s\n",
+		       smscusb, address, strerror ( rc ) );
+		return rc;
+	}
+	DBGCIO ( smscusb, "SMSCUSB %p [%03x] => %08x\n",
+		 smscusb, address, le32_to_cpu ( *value ) );
+
+	return 0;
+}
+
+/**
+ * Read register
+ *
+ * @v smscusb		SMSC USB device
+ * @v address		Register address
+ * @ret value		Register value
+ * @ret rc		Return status code
+ */
+static inline __attribute__ (( always_inline )) int
+smscusb_readl ( struct smscusb_device *smscusb, unsigned int address,
+		uint32_t *value ) {
+	int rc;
+
+	/* Read register */
+	if ( ( rc = smscusb_raw_readl ( smscusb, address, value ) ) != 0 )
+		return rc;
+	le32_to_cpus ( value );
+
+	return 0;
+}
+
+/**
+ * Get statistics
+ *
+ * @v smscusb		SMSC USB device
+ * @v index		Statistics set index
+ * @v data		Statistics data to fill in
+ * @v len		Length of statistics data
+ * @ret rc		Return status code
+ */
+static inline __attribute__ (( always_inline )) int
+smscusb_get_statistics ( struct smscusb_device *smscusb, unsigned int index,
+			 void *data, size_t len ) {
+	int rc;
+
+	/* Read statistics */
+	if ( ( rc = usb_control ( smscusb->usb, SMSCUSB_GET_STATISTICS, 0,
+				  index, data, len ) ) != 0 ) {
+		DBGC ( smscusb, "SMSCUSB %p could not get statistics set %d: "
+		       "%s\n", smscusb, index, strerror ( rc ) );
+		return rc;
+	}
+
+	return 0;
+}
+
+/** Interrupt maximum fill level
+ *
+ * This is a policy decision.
+ */
+#define SMSCUSB_INTR_MAX_FILL 2
+
+extern struct usb_endpoint_driver_operations smscusb_intr_operations;
+extern struct usb_endpoint_driver_operations smscusb_out_operations;
+extern struct mii_operations smscusb_mii_operations;
+
+/**
+ * Initialise SMSC USB device
+ *
+ * @v smscusb		SMSC USB device
+ * @v netdev		Network device
+ * @v func		USB function
+ * @v in		Bulk IN endpoint operations
+ */
+static inline __attribute__ (( always_inline )) void
+smscusb_init ( struct smscusb_device *smscusb, struct net_device *netdev,
+	       struct usb_function *func,
+	       struct usb_endpoint_driver_operations *in ) {
+	struct usb_device *usb = func->usb;
+
+	smscusb->usb = usb;
+	smscusb->bus = usb->port->hub->bus;
+	smscusb->netdev = netdev;
+	usbnet_init ( &smscusb->usbnet, func, &smscusb_intr_operations, in,
+		      &smscusb_out_operations );
+	usb_refill_init ( &smscusb->usbnet.intr, 0, 0, SMSCUSB_INTR_MAX_FILL );
+}
+
+/**
+ * Initialise SMSC USB device MII interface
+ *
+ * @v smscusb		SMSC USB device
+ * @v mii_base		MII register base
+ */
+static inline __attribute__ (( always_inline )) void
+smscusb_mii_init ( struct smscusb_device *smscusb, unsigned int mii_base ) {
+
+	mii_init ( &smscusb->mii, &smscusb_mii_operations );
+	smscusb->mii_base = mii_base;
+}
+
+extern int smscusb_eeprom_fetch_mac ( struct smscusb_device *smscusb,
+				      unsigned int e2p_base );
+extern int smscusb_mii_check_link ( struct smscusb_device *smscusb );
+extern int smscusb_mii_open ( struct smscusb_device *smscusb );
+extern int smscusb_set_address ( struct smscusb_device *smscusb,
+				 unsigned int addr_base );
+extern int smscusb_set_filter ( struct smscusb_device *smscusb,
+				unsigned int filt_base );
+
+#endif /* _SMSCUSB_H */