drivers/net/usb/catc.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *  Copyright (c) 2001 Vojtech Pavlik
 *
 *  CATC EL1210A NetMate USB Ethernet driver
 *
 *  Sponsored by SuSE
 *
 *  Based on the work of
 *		Donald Becker
 *
 *  Old chipset support added by Simon Evans <spse@secret.org.uk> 2002
 *    - adds support for Belkin F5U011
 */

/*
 *
 * Should you need to contact me, the author, you can do so either by
 * e-mail - mail your message to <vojtech@suse.cz>, or by paper mail:
 * Vojtech Pavlik, Simunkova 1594, Prague 8, 182 00 Czech Republic
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/skbuff.h>
#include <linux/spinlock.h>
#include <linux/ethtool.h>
#include <linux/crc32.h>
#include <linux/bitops.h>
#include <linux/gfp.h>
#include <linux/uaccess.h>

#undef DEBUG

#include <linux/usb.h>

/*
 * Version information.
 */

#define DRIVER_VERSION "v2.8"
#define DRIVER_AUTHOR "Vojtech Pavlik <vojtech@suse.cz>"
#define DRIVER_DESC "CATC EL1210A NetMate USB Ethernet driver"
#define SHORT_DRIVER_DESC "EL1210A NetMate USB Ethernet"

MODULE_AUTHOR(DRIVER_AUTHOR);
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");

static const char driver_name[] = "catc";

/*
 * Some defines.
 */

#define STATS_UPDATE		(HZ)	/* Time between stats updates */
#define TX_TIMEOUT		(5*HZ)	/* Max time the queue can be stopped */
#define PKT_SZ			1536	/* Max Ethernet packet size */
#define RX_MAX_BURST		15	/* Max packets per rx buffer (> 0, < 16) */
#define TX_MAX_BURST		15	/* Max full sized packets per tx buffer (> 0) */
#define CTRL_QUEUE		16	/* Max control requests in flight (power of two) */
#define RX_PKT_SZ		1600	/* Max size of receive packet for F5U011 */

/*
 * Control requests.
 */

enum control_requests {
	ReadMem =	0xf1,
	GetMac =	0xf2,
	Reset =		0xf4,
	SetMac =	0xf5,
	SetRxMode =     0xf5,  /* F5U011 only */
	WriteROM =	0xf8,
	SetReg =	0xfa,
	GetReg =	0xfb,
	WriteMem =	0xfc,
	ReadROM =	0xfd,
};

/*
 * Registers.
 */

enum register_offsets {
	TxBufCount =	0x20,
	RxBufCount =	0x21,
	OpModes =	0x22,
	TxQed =		0x23,
	RxQed =		0x24,
	MaxBurst =	0x25,
	RxUnit =	0x60,
	EthStatus =	0x61,
	StationAddr0 =	0x67,
	EthStats =	0x69,
	LEDCtrl =	0x81,
};

enum eth_stats {
	TxSingleColl =	0x00,
        TxMultiColl =	0x02,
        TxExcessColl =	0x04,
        RxFramErr =	0x06,
};

enum op_mode_bits {
	Op3MemWaits =	0x03,
	OpLenInclude =	0x08,
	OpRxMerge =	0x10,
	OpTxMerge =	0x20,
	OpWin95bugfix =	0x40,
	OpLoopback =	0x80,
};

enum rx_filter_bits {
	RxEnable =	0x01,
	RxPolarity =	0x02,
	RxForceOK =	0x04,
	RxMultiCast =	0x08,
	RxPromisc =	0x10,
	AltRxPromisc =  0x20, /* F5U011 uses different bit */
};

enum led_values {
	LEDFast = 	0x01,
	LEDSlow =	0x02,
	LEDFlash =	0x03,
	LEDPulse =	0x04,
	LEDLink =	0x08,
};

enum link_status {
	LinkNoChange = 0,
	LinkGood     = 1,
	LinkBad      = 2
};

/*
 * The catc struct.
 */

#define CTRL_RUNNING	0
#define RX_RUNNING	1
#define TX_RUNNING	2

struct catc {
	struct net_device *netdev;
	struct usb_device *usbdev;

	unsigned long flags;

	unsigned int tx_ptr, tx_idx;
	unsigned int ctrl_head, ctrl_tail;
	spinlock_t tx_lock, ctrl_lock;

	u8 tx_buf[2][TX_MAX_BURST * (PKT_SZ + 2)];
	u8 rx_buf[RX_MAX_BURST * (PKT_SZ + 2)];
	u8 irq_buf[2];
	u8 ctrl_buf[64];
	struct usb_ctrlrequest ctrl_dr;

	struct timer_list timer;
	u8 stats_buf[8];
	u16 stats_vals[4];
	unsigned long last_stats;

	u8 multicast[64];

	struct ctrl_queue {
		u8 dir;
		u8 request;
		u16 value;
		u16 index;
		void *buf;
		int len;
		void (*callback)(struct catc *catc, struct ctrl_queue *q);
	} ctrl_queue[CTRL_QUEUE];

	struct urb *tx_urb, *rx_urb, *irq_urb, *ctrl_urb;

	u8 is_f5u011;	/* Set if device is an F5U011 */
	u8 rxmode[2];	/* Used for F5U011 */
	atomic_t recq_sz; /* Used for F5U011 - counter of waiting rx packets */
};

/*
 * Useful macros.
 */

#define catc_get_mac(catc, mac)				catc_ctrl_msg(catc, USB_DIR_IN,  GetMac, 0, 0, mac,  6)
#define catc_reset(catc)				catc_ctrl_msg(catc, USB_DIR_OUT, Reset, 0, 0, NULL, 0)
#define catc_set_reg(catc, reg, val)			catc_ctrl_msg(catc, USB_DIR_OUT, SetReg, val, reg, NULL, 0)
#define catc_get_reg(catc, reg, buf)			catc_ctrl_msg(catc, USB_DIR_IN,  GetReg, 0, reg, buf, 1)
#define catc_write_mem(catc, addr, buf, size)		catc_ctrl_msg(catc, USB_DIR_OUT, WriteMem, 0, addr, buf, size)
#define catc_read_mem(catc, addr, buf, size)		catc_ctrl_msg(catc, USB_DIR_IN,  ReadMem, 0, addr, buf, size)

#define f5u011_rxmode(catc, rxmode)			catc_ctrl_msg(catc, USB_DIR_OUT, SetRxMode, 0, 1, rxmode, 2)
#define f5u011_rxmode_async(catc, rxmode)		catc_ctrl_async(catc, USB_DIR_OUT, SetRxMode, 0, 1, &rxmode, 2, NULL)
#define f5u011_mchash_async(catc, hash)			catc_ctrl_async(catc, USB_DIR_OUT, SetRxMode, 0, 2, &hash, 8, NULL)

#define catc_set_reg_async(catc, reg, val)		catc_ctrl_async(catc, USB_DIR_OUT, SetReg, val, reg, NULL, 0, NULL)
#define catc_get_reg_async(catc, reg, cb)		catc_ctrl_async(catc, USB_DIR_IN, GetReg, 0, reg, NULL, 1, cb)
#define catc_write_mem_async(catc, addr, buf, size)	catc_ctrl_async(catc, USB_DIR_OUT, WriteMem, 0, addr, buf, size, NULL)

/*
 * Receive routines.
 */

static void catc_rx_done(struct urb *urb)
{
	struct catc *catc = urb->context;
	u8 *pkt_start = urb->transfer_buffer;
	struct sk_buff *skb;
	int pkt_len, pkt_offset = 0;
	int status = urb->status;

	if (!catc->is_f5u011) {
		clear_bit(RX_RUNNING, &catc->flags);
		pkt_offset = 2;
	}

	if (status) {
		dev_dbg(&urb->dev->dev, "rx_done, status %d, length %d\n",
			status, urb->actual_length);
		return;
	}

	do {
		if(!catc->is_f5u011) {
			pkt_len = le16_to_cpup((__le16*)pkt_start);
			if (pkt_len > urb->actual_length) {
				catc->netdev->stats.rx_length_errors++;
				catc->netdev->stats.rx_errors++;
				break;
			}
		} else {
			pkt_len = urb->actual_length;
		}

		if (!(skb = dev_alloc_skb(pkt_len)))
			return;

		skb_copy_to_linear_data(skb, pkt_start + pkt_offset, pkt_len);
		skb_put(skb, pkt_len);

		skb->protocol = eth_type_trans(skb, catc->netdev);
		netif_rx(skb);

		catc->netdev->stats.rx_packets++;
		catc->netdev->stats.rx_bytes += pkt_len;

		/* F5U011 only does one packet per RX */
		if (catc->is_f5u011)
			break;
		pkt_start += (((pkt_len + 1) >> 6) + 1) << 6;

	} while (pkt_start - (u8 *) urb->transfer_buffer < urb->actual_length);

	if (catc->is_f5u011) {
		if (atomic_read(&catc->recq_sz)) {
			int state;
			atomic_dec(&catc->recq_sz);
			netdev_dbg(catc->netdev, "getting extra packet\n");
			urb->dev = catc->usbdev;
			if ((state = usb_submit_urb(urb, GFP_ATOMIC)) < 0) {
				netdev_dbg(catc->netdev,
					   "submit(rx_urb) status %d\n", state);
			}
		} else {
			clear_bit(RX_RUNNING, &catc->flags);
		}
	}
}

static void catc_irq_done(struct urb *urb)
{
	struct catc *catc = urb->context;
	u8 *data = urb->transfer_buffer;
	int status = urb->status;
	unsigned int hasdata, linksts = LinkNoChange;
	int res;

	if (!catc->is_f5u011) {
		hasdata = data[1] & 0x80;
		if (data[1] & 0x40)
			linksts = LinkGood;
		else if (data[1] & 0x20)
			linksts = LinkBad;
	} else {
		hasdata = (unsigned int)(be16_to_cpup((__be16*)data) & 0x0fff);
		if (data[0] == 0x90)
			linksts = LinkGood;
		else if (data[0] == 0xA0)
			linksts = LinkBad;
	}

	switch (status) {
	case 0:			/* success */
		break;
	case -ECONNRESET:	/* unlink */
	case -ENOENT:
	case -ESHUTDOWN:
		return;
	/* -EPIPE:  should clear the halt */
	default:		/* error */
		dev_dbg(&urb->dev->dev,
			"irq_done, status %d, data %02x %02x.\n",
			status, data[0], data[1]);
		goto resubmit;
	}

	if (linksts == LinkGood) {
		netif_carrier_on(catc->netdev);
		netdev_dbg(catc->netdev, "link ok\n");
	}

	if (linksts == LinkBad) {
		netif_carrier_off(catc->netdev);
		netdev_dbg(catc->netdev, "link bad\n");
	}

	if (hasdata) {
		if (test_and_set_bit(RX_RUNNING, &catc->flags)) {
			if (catc->is_f5u011)
				atomic_inc(&catc->recq_sz);
		} else {
			catc->rx_urb->dev = catc->usbdev;
			if ((res = usb_submit_urb(catc->rx_urb, GFP_ATOMIC)) < 0) {
				dev_err(&catc->usbdev->dev,
					"submit(rx_urb) status %d\n", res);
			}
		}
	}
resubmit:
	res = usb_submit_urb (urb, GFP_ATOMIC);
	if (res)
		dev_err(&catc->usbdev->dev,
			"can't resubmit intr, %s-%s, status %d\n",
			catc->usbdev->bus->bus_name,
			catc->usbdev->devpath, res);
}

/*
 * Transmit routines.
 */

static int catc_tx_run(struct catc *catc)
{
	int status;

	if (catc->is_f5u011)
		catc->tx_ptr = (catc->tx_ptr + 63) & ~63;

	catc->tx_urb->transfer_buffer_length = catc->tx_ptr;
	catc->tx_urb->transfer_buffer = catc->tx_buf[catc->tx_idx];
	catc->tx_urb->dev = catc->usbdev;

	if ((status = usb_submit_urb(catc->tx_urb, GFP_ATOMIC)) < 0)
		dev_err(&catc->usbdev->dev, "submit(tx_urb), status %d\n",
			status);

	catc->tx_idx = !catc->tx_idx;
	catc->tx_ptr = 0;

	netif_trans_update(catc->netdev);
	return status;
}

static void catc_tx_done(struct urb *urb)
{
	struct catc *catc = urb->context;
	unsigned long flags;
	int r, status = urb->status;

	if (status == -ECONNRESET) {
		dev_dbg(&urb->dev->dev, "Tx Reset.\n");
		urb->status = 0;
		netif_trans_update(catc->netdev);
		catc->netdev->stats.tx_errors++;
		clear_bit(TX_RUNNING, &catc->flags);
		netif_wake_queue(catc->netdev);
		return;
	}

	if (status) {
		dev_dbg(&urb->dev->dev, "tx_done, status %d, length %d\n",
			status, urb->actual_length);
		return;
	}

	spin_lock_irqsave(&catc->tx_lock, flags);

	if (catc->tx_ptr) {
		r = catc_tx_run(catc);
		if (unlikely(r < 0))
			clear_bit(TX_RUNNING, &catc->flags);
	} else {
		clear_bit(TX_RUNNING, &catc->flags);
	}

	netif_wake_queue(catc->netdev);

	spin_unlock_irqrestore(&catc->tx_lock, flags);
}

static netdev_tx_t catc_start_xmit(struct sk_buff *skb,
					 struct net_device *netdev)
{
	struct catc *catc = netdev_priv(netdev);
	unsigned long flags;
	int r = 0;
	char *tx_buf;

	spin_lock_irqsave(&catc->tx_lock, flags);

	catc->tx_ptr = (((catc->tx_ptr - 1) >> 6) + 1) << 6;
	tx_buf = catc->tx_buf[catc->tx_idx] + catc->tx_ptr;
	if (catc->is_f5u011)
		*(__be16 *)tx_buf = cpu_to_be16(skb->len);
	else
		*(__le16 *)tx_buf = cpu_to_le16(skb->len);
	skb_copy_from_linear_data(skb, tx_buf + 2, skb->len);
	catc->tx_ptr += skb->len + 2;

	if (!test_and_set_bit(TX_RUNNING, &catc->flags)) {
		r = catc_tx_run(catc);
		if (r < 0)
			clear_bit(TX_RUNNING, &catc->flags);
	}

	if ((catc->is_f5u011 && catc->tx_ptr) ||
	    (catc->tx_ptr >= ((TX_MAX_BURST - 1) * (PKT_SZ + 2))))
		netif_stop_queue(netdev);

	spin_unlock_irqrestore(&catc->tx_lock, flags);

	if (r >= 0) {
		catc->netdev->stats.tx_bytes += skb->len;
		catc->netdev->stats.tx_packets++;
	}

	dev_kfree_skb(skb);

	return NETDEV_TX_OK;
}

static void catc_tx_timeout(struct net_device *netdev, unsigned int txqueue)
{
	struct catc *catc = netdev_priv(netdev);

	dev_warn(&netdev->dev, "Transmit timed out.\n");
	usb_unlink_urb(catc->tx_urb);
}

/*
 * Control messages.
 */

static int catc_ctrl_msg(struct catc *catc, u8 dir, u8 request, u16 value, u16 index, void *buf, int len)
{
        int retval = usb_control_msg(catc->usbdev,
		dir ? usb_rcvctrlpipe(catc->usbdev, 0) : usb_sndctrlpipe(catc->usbdev, 0),
		 request, 0x40 | dir, value, index, buf, len, 1000);
        return retval < 0 ? retval : 0;
}

static void catc_ctrl_run(struct catc *catc)
{
	struct ctrl_queue *q = catc->ctrl_queue + catc->ctrl_tail;
	struct usb_device *usbdev = catc->usbdev;
	struct urb *urb = catc->ctrl_urb;
	struct usb_ctrlrequest *dr = &catc->ctrl_dr;
	int status;

	dr->bRequest = q->request;
	dr->bRequestType = 0x40 | q->dir;
	dr->wValue = cpu_to_le16(q->value);
	dr->wIndex = cpu_to_le16(q->index);
	dr->wLength = cpu_to_le16(q->len);

        urb->pipe = q->dir ? usb_rcvctrlpipe(usbdev, 0) : usb_sndctrlpipe(usbdev, 0);
	urb->transfer_buffer_length = q->len;
	urb->transfer_buffer = catc->ctrl_buf;
	urb->setup_packet = (void *) dr;
	urb->dev = usbdev;

	if (!q->dir && q->buf && q->len)
		memcpy(catc->ctrl_buf, q->buf, q->len);

	if ((status = usb_submit_urb(catc->ctrl_urb, GFP_ATOMIC)))
		dev_err(&catc->usbdev->dev, "submit(ctrl_urb) status %d\n",
			status);
}

static void catc_ctrl_done(struct urb *urb)
{
	struct catc *catc = urb->context;
	struct ctrl_queue *q;
	unsigned long flags;
	int status = urb->status;

	if (status)
		dev_dbg(&urb->dev->dev, "ctrl_done, status %d, len %d.\n",
			status, urb->actual_length);

	spin_lock_irqsave(&catc->ctrl_lock, flags);

	q = catc->ctrl_queue + catc->ctrl_tail;

	if (q->dir) {
		if (q->buf && q->len)
			memcpy(q->buf, catc->ctrl_buf, q->len);
		else
			q->buf = catc->ctrl_buf;
	}

	if (q->callback)
		q->callback(catc, q);

	catc->ctrl_tail = (catc->ctrl_tail + 1) & (CTRL_QUEUE - 1);

	if (catc->ctrl_head != catc->ctrl_tail)
		catc_ctrl_run(catc);
	else
		clear_bit(CTRL_RUNNING, &catc->flags);

	spin_unlock_irqrestore(&catc->ctrl_lock, flags);
}

static int catc_ctrl_async(struct catc *catc, u8 dir, u8 request, u16 value,
	u16 index, void *buf, int len, void (*callback)(struct catc *catc, struct ctrl_queue *q))
{
	struct ctrl_queue *q;
	int retval = 0;
	unsigned long flags;

	spin_lock_irqsave(&catc->ctrl_lock, flags);

	q = catc->ctrl_queue + catc->ctrl_head;

	q->dir = dir;
	q->request = request;
	q->value = value;
	q->index = index;
	q->buf = buf;
	q->len = len;
	q->callback = callback;

	catc->ctrl_head = (catc->ctrl_head + 1) & (CTRL_QUEUE - 1);

	if (catc->ctrl_head == catc->ctrl_tail) {
		dev_err(&catc->usbdev->dev, "ctrl queue full\n");
		catc->ctrl_tail = (catc->ctrl_tail + 1) & (CTRL_QUEUE - 1);
		retval = -1;
	}

	if (!test_and_set_bit(CTRL_RUNNING, &catc->flags))
		catc_ctrl_run(catc);

	spin_unlock_irqrestore(&catc->ctrl_lock, flags);

	return retval;
}

/*
 * Statistics.
 */

static void catc_stats_done(struct catc *catc, struct ctrl_queue *q)
{
	int index = q->index - EthStats;
	u16 data, last;

	catc->stats_buf[index] = *((char *)q->buf);

	if (index & 1)
		return;

	data = ((u16)catc->stats_buf[index] << 8) | catc->stats_buf[index + 1];
	last = catc->stats_vals[index >> 1];

	switch (index) {
		case TxSingleColl:
		case TxMultiColl:
			catc->netdev->stats.collisions += data - last;
			break;
		case TxExcessColl:
			catc->netdev->stats.tx_aborted_errors += data - last;
			catc->netdev->stats.tx_errors += data - last;
			break;
		case RxFramErr:
			catc->netdev->stats.rx_frame_errors += data - last;
			catc->netdev->stats.rx_errors += data - last;
			break;
	}

	catc->stats_vals[index >> 1] = data;
}

static void catc_stats_timer(struct timer_list *t)
{
	struct catc *catc = from_timer(catc, t, timer);
	int i;

	for (i = 0; i < 8; i++)
		catc_get_reg_async(catc, EthStats + 7 - i, catc_stats_done);

	mod_timer(&catc->timer, jiffies + STATS_UPDATE);
}

/*
 * Receive modes. Broadcast, Multicast, Promisc.
 */

static void catc_multicast(const unsigned char *addr, u8 *multicast)
{
	u32 crc;

	crc = ether_crc_le(6, addr);
	multicast[(crc >> 3) & 0x3f] |= 1 << (crc & 7);
}

static void catc_set_multicast_list(struct net_device *netdev)
{
	struct catc *catc = netdev_priv(netdev);
	struct netdev_hw_addr *ha;
	u8 broadcast[ETH_ALEN];
	u8 rx = RxEnable | RxPolarity | RxMultiCast;

	eth_broadcast_addr(broadcast);
	memset(catc->multicast, 0, 64);

	catc_multicast(broadcast, catc->multicast);
	catc_multicast(netdev->dev_addr, catc->multicast);

	if (netdev->flags & IFF_PROMISC) {
		memset(catc->multicast, 0xff, 64);
		rx |= (!catc->is_f5u011) ? RxPromisc : AltRxPromisc;
	}

	if (netdev->flags & IFF_ALLMULTI) {
		memset(catc->multicast, 0xff, 64);
	} else {
		netdev_for_each_mc_addr(ha, netdev) {
			u32 crc = ether_crc_le(6, ha->addr);
			if (!catc->is_f5u011) {
				catc->multicast[(crc >> 3) & 0x3f] |= 1 << (crc & 7);
			} else {
				catc->multicast[7-(crc >> 29)] |= 1 << ((crc >> 26) & 7);
			}
		}
	}
	if (!catc->is_f5u011) {
		catc_set_reg_async(catc, RxUnit, rx);
		catc_write_mem_async(catc, 0xfa80, catc->multicast, 64);
	} else {
		f5u011_mchash_async(catc, catc->multicast);
		if (catc->rxmode[0] != rx) {
			catc->rxmode[0] = rx;
			netdev_dbg(catc->netdev,
				   "Setting RX mode to %2.2X %2.2X\n",
				   catc->rxmode[0], catc->rxmode[1]);
			f5u011_rxmode_async(catc, catc->rxmode);
		}
	}
}

static void catc_get_drvinfo(struct net_device *dev,
			     struct ethtool_drvinfo *info)
{
	struct catc *catc = netdev_priv(dev);
	strlcpy(info->driver, driver_name, sizeof(info->driver));
	strlcpy(info->version, DRIVER_VERSION, sizeof(info->version));
	usb_make_path(catc->usbdev, info->bus_info, sizeof(info->bus_info));
}

static int catc_get_link_ksettings(struct net_device *dev,
				   struct ethtool_link_ksettings *cmd)
{
	struct catc *catc = netdev_priv(dev);
	if (!catc->is_f5u011)
		return -EOPNOTSUPP;

	ethtool_link_ksettings_zero_link_mode(cmd, supported);
	ethtool_link_ksettings_add_link_mode(cmd, supported, 10baseT_Half);
	ethtool_link_ksettings_add_link_mode(cmd, supported, TP);

	ethtool_link_ksettings_zero_link_mode(cmd, advertising);
	ethtool_link_ksettings_add_link_mode(cmd, advertising, 10baseT_Half);
	ethtool_link_ksettings_add_link_mode(cmd, advertising, TP);

	cmd->base.speed = SPEED_10;
	cmd->base.duplex = DUPLEX_HALF;
	cmd->base.port = PORT_TP;
	cmd->base.phy_address = 0;
	cmd->base.autoneg = AUTONEG_DISABLE;

	return 0;
}

static const struct ethtool_ops ops = {
	.get_drvinfo = catc_get_drvinfo,
	.get_link = ethtool_op_get_link,
	.get_link_ksettings = catc_get_link_ksettings,
};

/*
 * Open, close.
 */

static int catc_open(struct net_device *netdev)
{
	struct catc *catc = netdev_priv(netdev);
	int status;

	catc->irq_urb->dev = catc->usbdev;
	if ((status = usb_submit_urb(catc->irq_urb, GFP_KERNEL)) < 0) {
		dev_err(&catc->usbdev->dev, "submit(irq_urb) status %d\n",
			status);
		return -1;
	}

	netif_start_queue(netdev);

	if (!catc->is_f5u011)
		mod_timer(&catc->timer, jiffies + STATS_UPDATE);

	return 0;
}

static int catc_stop(struct net_device *netdev)
{
	struct catc *catc = netdev_priv(netdev);

	netif_stop_queue(netdev);

	if (!catc->is_f5u011)
		del_timer_sync(&catc->timer);

	usb_kill_urb(catc->rx_urb);
	usb_kill_urb(catc->tx_urb);
	usb_kill_urb(catc->irq_urb);
	usb_kill_urb(catc->ctrl_urb);

	return 0;
}

static const struct net_device_ops catc_netdev_ops = {
	.ndo_open		= catc_open,
	.ndo_stop		= catc_stop,
	.ndo_start_xmit		= catc_start_xmit,

	.ndo_tx_timeout		= catc_tx_timeout,
	.ndo_set_rx_mode	= catc_set_multicast_list,
	.ndo_set_mac_address 	= eth_mac_addr,
	.ndo_validate_addr	= eth_validate_addr,
};

/*
 * USB probe, disconnect.
 */

static int catc_probe(struct usb_interface *intf, const struct usb_device_id *id)
{
	struct device *dev = &intf->dev;
	struct usb_device *usbdev = interface_to_usbdev(intf);
	struct net_device *netdev;
	struct catc *catc;
	u8 broadcast[ETH_ALEN];
	u8 *macbuf;
	int pktsz, ret = -ENOMEM;

	macbuf = kmalloc(ETH_ALEN, GFP_KERNEL);
	if (!macbuf)
		goto error;

	if (usb_set_interface(usbdev,
			intf->altsetting->desc.bInterfaceNumber, 1)) {
		dev_err(dev, "Can't set altsetting 1.\n");
		ret = -EIO;
		goto fail_mem;
	}

	netdev = alloc_etherdev(sizeof(struct catc));
	if (!netdev)
		goto fail_mem;

	catc = netdev_priv(netdev);

	netdev->netdev_ops = &catc_netdev_ops;
	netdev->watchdog_timeo = TX_TIMEOUT;
	netdev->ethtool_ops = &ops;

	catc->usbdev = usbdev;
	catc->netdev = netdev;

	spin_lock_init(&catc->tx_lock);
	spin_lock_init(&catc->ctrl_lock);

	timer_setup(&catc->timer, catc_stats_timer, 0);

	catc->ctrl_urb = usb_alloc_urb(0, GFP_KERNEL);
	catc->tx_urb = usb_alloc_urb(0, GFP_KERNEL);
	catc->rx_urb = usb_alloc_urb(0, GFP_KERNEL);
	catc->irq_urb = usb_alloc_urb(0, GFP_KERNEL);
	if ((!catc->ctrl_urb) || (!catc->tx_urb) ||
	    (!catc->rx_urb) || (!catc->irq_urb)) {
		dev_err(&intf->dev, "No free urbs available.\n");
		ret = -ENOMEM;
		goto fail_free;
	}

	/* The F5U011 has the same vendor/product as the netmate but a device version of 0x130 */
	if (le16_to_cpu(usbdev->descriptor.idVendor) == 0x0423 &&
	    le16_to_cpu(usbdev->descriptor.idProduct) == 0xa &&
	    le16_to_cpu(catc->usbdev->descriptor.bcdDevice) == 0x0130) {
		dev_dbg(dev, "Testing for f5u011\n");
		catc->is_f5u011 = 1;
		atomic_set(&catc->recq_sz, 0);
		pktsz = RX_PKT_SZ;
	} else {
		pktsz = RX_MAX_BURST * (PKT_SZ + 2);
	}

	usb_fill_control_urb(catc->ctrl_urb, usbdev, usb_sndctrlpipe(usbdev, 0),
		NULL, NULL, 0, catc_ctrl_done, catc);

	usb_fill_bulk_urb(catc->tx_urb, usbdev, usb_sndbulkpipe(usbdev, 1),
		NULL, 0, catc_tx_done, catc);

	usb_fill_bulk_urb(catc->rx_urb, usbdev, usb_rcvbulkpipe(usbdev, 1),
		catc->rx_buf, pktsz, catc_rx_done, catc);

	usb_fill_int_urb(catc->irq_urb, usbdev, usb_rcvintpipe(usbdev, 2),
                catc->irq_buf, 2, catc_irq_done, catc, 1);

	if (!catc->is_f5u011) {
		u32 *buf;
		int i;

		dev_dbg(dev, "Checking memory size\n");

		buf = kmalloc(4, GFP_KERNEL);
		if (!buf) {
			ret = -ENOMEM;
			goto fail_free;
		}

		*buf = 0x12345678;
		catc_write_mem(catc, 0x7a80, buf, 4);
		*buf = 0x87654321;
		catc_write_mem(catc, 0xfa80, buf, 4);
		catc_read_mem(catc, 0x7a80, buf, 4);

		switch (*buf) {
		case 0x12345678:
			catc_set_reg(catc, TxBufCount, 8);
			catc_set_reg(catc, RxBufCount, 32);
			dev_dbg(dev, "64k Memory\n");
			break;
		default:
			dev_warn(&intf->dev,
				 "Couldn't detect memory size, assuming 32k\n");
			fallthrough;
		case 0x87654321:
			catc_set_reg(catc, TxBufCount, 4);
			catc_set_reg(catc, RxBufCount, 16);
			dev_dbg(dev, "32k Memory\n");
			break;
		}

		kfree(buf);

		dev_dbg(dev, "Getting MAC from SEEROM.\n");

		catc_get_mac(catc, macbuf);
		eth_hw_addr_set(netdev, macbuf);

		dev_dbg(dev, "Setting MAC into registers.\n");

		for (i = 0; i < 6; i++)
			catc_set_reg(catc, StationAddr0 - i, netdev->dev_addr[i]);

		dev_dbg(dev, "Filling the multicast list.\n");

		eth_broadcast_addr(broadcast);
		catc_multicast(broadcast, catc->multicast);
		catc_multicast(netdev->dev_addr, catc->multicast);
		catc_write_mem(catc, 0xfa80, catc->multicast, 64);

		dev_dbg(dev, "Clearing error counters.\n");

		for (i = 0; i < 8; i++)
			catc_set_reg(catc, EthStats + i, 0);
		catc->last_stats = jiffies;

		dev_dbg(dev, "Enabling.\n");

		catc_set_reg(catc, MaxBurst, RX_MAX_BURST);
		catc_set_reg(catc, OpModes, OpTxMerge | OpRxMerge | OpLenInclude | Op3MemWaits);
		catc_set_reg(catc, LEDCtrl, LEDLink);
		catc_set_reg(catc, RxUnit, RxEnable | RxPolarity | RxMultiCast);
	} else {
		dev_dbg(dev, "Performing reset\n");
		catc_reset(catc);
		catc_get_mac(catc, macbuf);
		eth_hw_addr_set(netdev, macbuf);

		dev_dbg(dev, "Setting RX Mode\n");
		catc->rxmode[0] = RxEnable | RxPolarity | RxMultiCast;
		catc->rxmode[1] = 0;
		f5u011_rxmode(catc, catc->rxmode);
	}
	dev_dbg(dev, "Init done.\n");
	printk(KERN_INFO "%s: %s USB Ethernet at usb-%s-%s, %pM.\n",
	       netdev->name, (catc->is_f5u011) ? "Belkin F5U011" : "CATC EL1210A NetMate",
	       usbdev->bus->bus_name, usbdev->devpath, netdev->dev_addr);
	usb_set_intfdata(intf, catc);

	SET_NETDEV_DEV(netdev, &intf->dev);
	ret = register_netdev(netdev);
	if (ret)
		goto fail_clear_intfdata;

	kfree(macbuf);
	return 0;

fail_clear_intfdata:
	usb_set_intfdata(intf, NULL);
fail_free:
	usb_free_urb(catc->ctrl_urb);
	usb_free_urb(catc->tx_urb);
	usb_free_urb(catc->rx_urb);
	usb_free_urb(catc->irq_urb);
	free_netdev(netdev);
fail_mem:
	kfree(macbuf);
error:
	return ret;
}

static void catc_disconnect(struct usb_interface *intf)
{
	struct catc *catc = usb_get_intfdata(intf);

	usb_set_intfdata(intf, NULL);
	if (catc) {
		unregister_netdev(catc->netdev);
		usb_free_urb(catc->ctrl_urb);
		usb_free_urb(catc->tx_urb);
		usb_free_urb(catc->rx_urb);
		usb_free_urb(catc->irq_urb);
		free_netdev(catc->netdev);
	}
}

/*
 * Module functions and tables.
 */

static const struct usb_device_id catc_id_table[] = {
	{ USB_DEVICE(0x0423, 0xa) },	/* CATC Netmate, Belkin F5U011 */
	{ USB_DEVICE(0x0423, 0xc) },	/* CATC Netmate II, Belkin F5U111 */
	{ USB_DEVICE(0x08d1, 0x1) },	/* smartBridges smartNIC */
	{ }
};

MODULE_DEVICE_TABLE(usb, catc_id_table);

static struct usb_driver catc_driver = {
	.name =		driver_name,
	.probe =	catc_probe,
	.disconnect =	catc_disconnect,
	.id_table =	catc_id_table,
	.disable_hub_initiated_lpm = 1,
};

module_usb_driver(catc_driver);