// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Ethernet driver for the WIZnet W5100 chip.
 *
 * Copyright (C) 2006-2008 WIZnet Co.,Ltd.
 * Copyright (C) 2012 Mike Sinkovsky <msink@permonline.ru>
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/platform_device.h>
#include <linux/ethtool.h>
#include <linux/skbuff.h>
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/io.h>
#include <linux/ioport.h>
#include <linux/interrupt.h>
#include <linux/irq.h>

#include "w5100.h"

#define DRV_NAME        "w5100"
#define DRV_VERSION     "2012-04-04"

MODULE_DESCRIPTION("WIZnet W5100 Ethernet driver v"DRV_VERSION);
MODULE_AUTHOR("Mike Sinkovsky <msink@permonline.ru>");
MODULE_ALIAS("platform:"DRV_NAME);
MODULE_LICENSE("GPL");

/*
 * W5100/W5200/W5500 common registers
 */
#define W5100_COMMON_REGS       0x0000
#define W5100_MR                0x0000 /* Mode Register */
#define   MR_RST                  0x80 /* S/W reset */
#define   MR_PB                   0x10 /* Ping block */
#define   MR_AI                   0x02 /* Address Auto-Increment */
#define   MR_IND                  0x01 /* Indirect mode */
#define W5100_SHAR              0x0009 /* Source MAC address */
#define W5100_IR                0x0015 /* Interrupt Register */
#define W5100_COMMON_REGS_LEN   0x0040

#define W5100_Sn_MR             0x0000 /* Sn Mode Register */
#define W5100_Sn_CR             0x0001 /* Sn Command Register */
#define W5100_Sn_IR             0x0002 /* Sn Interrupt Register */
#define W5100_Sn_SR             0x0003 /* Sn Status Register */
#define W5100_Sn_TX_FSR         0x0020 /* Sn Transmit free memory size */
#define W5100_Sn_TX_RD          0x0022 /* Sn Transmit memory read pointer */
#define W5100_Sn_TX_WR          0x0024 /* Sn Transmit memory write pointer */
#define W5100_Sn_RX_RSR         0x0026 /* Sn Receive free memory size */
#define W5100_Sn_RX_RD          0x0028 /* Sn Receive memory read pointer */

#define S0_REGS(priv)           ((priv)->s0_regs)

#define W5100_S0_MR(priv)       (S0_REGS(priv) + W5100_Sn_MR)
#define   S0_MR_MACRAW            0x04 /* MAC RAW mode */
#define   S0_MR_MF                0x40 /* MAC Filter for W5100 and W5200 */
#define   W5500_S0_MR_MF          0x80 /* MAC Filter for W5500 */
#define W5100_S0_CR(priv)       (S0_REGS(priv) + W5100_Sn_CR)
#define   S0_CR_OPEN              0x01 /* OPEN command */
#define   S0_CR_CLOSE             0x10 /* CLOSE command */
#define   S0_CR_SEND              0x20 /* SEND command */
#define   S0_CR_RECV              0x40 /* RECV command */
#define W5100_S0_IR(priv)       (S0_REGS(priv) + W5100_Sn_IR)
#define   S0_IR_SENDOK            0x10 /* complete sending */
#define   S0_IR_RECV              0x04 /* receiving data */
#define W5100_S0_SR(priv)       (S0_REGS(priv) + W5100_Sn_SR)
#define   S0_SR_MACRAW            0x42 /* mac raw mode */
#define W5100_S0_TX_FSR(priv)   (S0_REGS(priv) + W5100_Sn_TX_FSR)
#define W5100_S0_TX_RD(priv)    (S0_REGS(priv) + W5100_Sn_TX_RD)
#define W5100_S0_TX_WR(priv)    (S0_REGS(priv) + W5100_Sn_TX_WR)
#define W5100_S0_RX_RSR(priv)   (S0_REGS(priv) + W5100_Sn_RX_RSR)
#define W5100_S0_RX_RD(priv)    (S0_REGS(priv) + W5100_Sn_RX_RD)

#define W5100_S0_REGS_LEN       0x0040

/*
 * W5100 and W5200 common registers
 */
#define W5100_IMR               0x0016 /* Interrupt Mask Register */
#define   IR_S0                   0x01 /* S0 interrupt */
#define W5100_RTR               0x0017 /* Retry Time-value Register */
#define   RTR_DEFAULT             2000 /* =0x07d0 (2000) */

/*
 * W5100 specific register and memory
 */
#define W5100_RMSR              0x001a /* Receive Memory Size */
#define W5100_TMSR              0x001b /* Transmit Memory Size */

#define W5100_S0_REGS           0x0400

#define W5100_TX_MEM_START      0x4000
#define W5100_TX_MEM_SIZE       0x2000
#define W5100_RX_MEM_START      0x6000
#define W5100_RX_MEM_SIZE       0x2000

/*
 * W5200 specific register and memory
 */
#define W5200_S0_REGS           0x4000

#define W5200_Sn_RXMEM_SIZE(n)  (0x401e + (n) * 0x0100) /* Sn RX Memory Size */
#define W5200_Sn_TXMEM_SIZE(n)  (0x401f + (n) * 0x0100) /* Sn TX Memory Size */

#define W5200_TX_MEM_START      0x8000
#define W5200_TX_MEM_SIZE       0x4000
#define W5200_RX_MEM_START      0xc000
#define W5200_RX_MEM_SIZE       0x4000

/*
 * W5500 specific register and memory
 *
 * W5500 register and memory are organized by multiple blocks.  Each one is
 * selected by 16bits offset address and 5bits block select bits.  So we
 * encode it into 32bits address. (lower 16bits is offset address and
 * upper 16bits is block select bits)
 */
#define W5500_SIMR              0x0018 /* Socket Interrupt Mask Register */
#define W5500_RTR               0x0019 /* Retry Time-value Register */

#define W5500_S0_REGS           0x10000

#define W5500_Sn_RXMEM_SIZE(n)  \
                (0x1001e + (n) * 0x40000) /* Sn RX Memory Size */
#define W5500_Sn_TXMEM_SIZE(n)  \
                (0x1001f + (n) * 0x40000) /* Sn TX Memory Size */

#define W5500_TX_MEM_START      0x20000
#define W5500_TX_MEM_SIZE       0x04000
#define W5500_RX_MEM_START      0x30000
#define W5500_RX_MEM_SIZE       0x04000

/*
 * Device driver private data structure
 */

struct w5100_priv {
        const struct w5100_ops *ops;

        /* Socket 0 register offset address */
        u32 s0_regs;
        /* Socket 0 TX buffer offset address and size */
        u32 s0_tx_buf;
        u16 s0_tx_buf_size;
        /* Socket 0 RX buffer offset address and size */
        u32 s0_rx_buf;
        u16 s0_rx_buf_size;

        int irq;

        struct napi_struct napi;
        struct net_device *ndev;
        bool promisc;
        u32 msg_enable;

        struct workqueue_struct *xfer_wq;
        struct work_struct rx_work;
        struct sk_buff *tx_skb;
        struct work_struct tx_work;
        struct work_struct setrx_work;
        struct work_struct restart_work;
};

static int w5100_read(struct w5100_priv *priv, u32 addr)
{
        return priv->ops->read(priv->ndev, addr);
}

static int w5100_write(struct w5100_priv *priv, u32 addr, u8 data)
{
        return priv->ops->write(priv->ndev, addr, data);
}

static int w5100_read16(struct w5100_priv *priv, u32 addr)
{
        return priv->ops->read16(priv->ndev, addr);
}

static int w5100_write16(struct w5100_priv *priv, u32 addr, u16 data)
{
        return priv->ops->write16(priv->ndev, addr, data);
}

static int w5100_readbulk(struct w5100_priv *priv, u32 addr, u8 *buf, int len)
{
        return priv->ops->readbulk(priv->ndev, addr, buf, len);
}

static int w5100_writebulk(struct w5100_priv *priv, u32 addr, const u8 *buf,
                           int len)
{
        return priv->ops->writebulk(priv->ndev, addr, buf, len);
}

static int w5100_readbuf(struct w5100_priv *priv, u16 offset, u8 *buf, int len)
{
        u32 addr;
        int remain = 0;
        int ret;
        const u32 mem_start = priv->s0_rx_buf;
        const u16 mem_size = priv->s0_rx_buf_size;

        offset %= mem_size;
        addr = mem_start + offset;

        if (offset + len > mem_size) {
                remain = (offset + len) % mem_size;
                len = mem_size - offset;
        }

        ret = w5100_readbulk(priv, addr, buf, len);
        if (ret || !remain)
                return ret;

        return w5100_readbulk(priv, mem_start, buf + len, remain);
}

static int w5100_writebuf(struct w5100_priv *priv, u16 offset, const u8 *buf,
                          int len)
{
        u32 addr;
        int ret;
        int remain = 0;
        const u32 mem_start = priv->s0_tx_buf;
        const u16 mem_size = priv->s0_tx_buf_size;

        offset %= mem_size;
        addr = mem_start + offset;

        if (offset + len > mem_size) {
                remain = (offset + len) % mem_size;
                len = mem_size - offset;
        }

        ret = w5100_writebulk(priv, addr, buf, len);
        if (ret || !remain)
                return ret;

        return w5100_writebulk(priv, mem_start, buf + len, remain);
}

static int w5100_reset(struct w5100_priv *priv)
{
        if (priv->ops->reset)
                return priv->ops->reset(priv->ndev);

        w5100_write(priv, W5100_MR, MR_RST);
        mdelay(5);
        w5100_write(priv, W5100_MR, MR_PB);

        return 0;
}

static int w5100_command(struct w5100_priv *priv, u16 cmd)
{
        unsigned long timeout;

        w5100_write(priv, W5100_S0_CR(priv), cmd);

        timeout = jiffies + msecs_to_jiffies(100);

        while (w5100_read(priv, W5100_S0_CR(priv)) != 0) {
                if (time_after(jiffies, timeout))
                        return -EIO;
                cpu_relax();
        }

        return 0;
}

static void w5100_write_macaddr(struct w5100_priv *priv)
{
        struct net_device *ndev = priv->ndev;

        w5100_writebulk(priv, W5100_SHAR, ndev->dev_addr, ETH_ALEN);
}

static void w5100_socket_intr_mask(struct w5100_priv *priv, u8 mask)
{
        u32 imr;

        if (priv->ops->chip_id == W5500)
                imr = W5500_SIMR;
        else
                imr = W5100_IMR;

        w5100_write(priv, imr, mask);
}

static void w5100_enable_intr(struct w5100_priv *priv)
{
        w5100_socket_intr_mask(priv, IR_S0);
}

static void w5100_disable_intr(struct w5100_priv *priv)
{
        w5100_socket_intr_mask(priv, 0);
}

static void w5100_memory_configure(struct w5100_priv *priv)
{
        /* Configure 16K of internal memory
         * as 8K RX buffer and 8K TX buffer
         */
        w5100_write(priv, W5100_RMSR, 0x03);
        w5100_write(priv, W5100_TMSR, 0x03);
}

static void w5200_memory_configure(struct w5100_priv *priv)
{
        int i;

        /* Configure internal RX memory as 16K RX buffer and
         * internal TX memory as 16K TX buffer
         */
        w5100_write(priv, W5200_Sn_RXMEM_SIZE(0), 0x10);
        w5100_write(priv, W5200_Sn_TXMEM_SIZE(0), 0x10);

        for (i = 1; i < 8; i++) {
                w5100_write(priv, W5200_Sn_RXMEM_SIZE(i), 0);
                w5100_write(priv, W5200_Sn_TXMEM_SIZE(i), 0);
        }
}

static void w5500_memory_configure(struct w5100_priv *priv)
{
        int i;

        /* Configure internal RX memory as 16K RX buffer and
         * internal TX memory as 16K TX buffer
         */
        w5100_write(priv, W5500_Sn_RXMEM_SIZE(0), 0x10);
        w5100_write(priv, W5500_Sn_TXMEM_SIZE(0), 0x10);

        for (i = 1; i < 8; i++) {
                w5100_write(priv, W5500_Sn_RXMEM_SIZE(i), 0);
                w5100_write(priv, W5500_Sn_TXMEM_SIZE(i), 0);
        }
}

static int w5100_hw_reset(struct w5100_priv *priv)
{
        u32 rtr;

        w5100_reset(priv);

        w5100_disable_intr(priv);
        w5100_write_macaddr(priv);

        switch (priv->ops->chip_id) {
        case W5100:
                w5100_memory_configure(priv);
                rtr = W5100_RTR;
                break;
        case W5200:
                w5200_memory_configure(priv);
                rtr = W5100_RTR;
                break;
        case W5500:
                w5500_memory_configure(priv);
                rtr = W5500_RTR;
                break;
        default:
                return -EINVAL;
        }

        if (w5100_read16(priv, rtr) != RTR_DEFAULT)
                return -ENODEV;

        return 0;
}

static void w5100_hw_start(struct w5100_priv *priv)
{
        u8 mode = S0_MR_MACRAW;

        if (!priv->promisc) {
                if (priv->ops->chip_id == W5500)
                        mode |= W5500_S0_MR_MF;
                else
                        mode |= S0_MR_MF;
        }

        w5100_write(priv, W5100_S0_MR(priv), mode);
        w5100_command(priv, S0_CR_OPEN);
        w5100_enable_intr(priv);
}

static void w5100_hw_close(struct w5100_priv *priv)
{
        w5100_disable_intr(priv);
        w5100_command(priv, S0_CR_CLOSE);
}

/***********************************************************************
 *
 *   Device driver functions / callbacks
 *
 ***********************************************************************/

static void w5100_get_drvinfo(struct net_device *ndev,
                              struct ethtool_drvinfo *info)
{
        strscpy(info->driver, DRV_NAME, sizeof(info->driver));
        strscpy(info->version, DRV_VERSION, sizeof(info->version));
        strscpy(info->bus_info, dev_name(ndev->dev.parent),
                sizeof(info->bus_info));
}

static u32 w5100_get_msglevel(struct net_device *ndev)
{
        struct w5100_priv *priv = netdev_priv(ndev);

        return priv->msg_enable;
}

static void w5100_set_msglevel(struct net_device *ndev, u32 value)
{
        struct w5100_priv *priv = netdev_priv(ndev);

        priv->msg_enable = value;
}

static int w5100_get_regs_len(struct net_device *ndev)
{
        return W5100_COMMON_REGS_LEN + W5100_S0_REGS_LEN;
}

static void w5100_get_regs(struct net_device *ndev,
                           struct ethtool_regs *regs, void *buf)
{
        struct w5100_priv *priv = netdev_priv(ndev);

        regs->version = 1;
        w5100_readbulk(priv, W5100_COMMON_REGS, buf, W5100_COMMON_REGS_LEN);
        buf += W5100_COMMON_REGS_LEN;
        w5100_readbulk(priv, S0_REGS(priv), buf, W5100_S0_REGS_LEN);
}

static void w5100_restart(struct net_device *ndev)
{
        struct w5100_priv *priv = netdev_priv(ndev);

        netif_stop_queue(ndev);
        w5100_hw_reset(priv);
        w5100_hw_start(priv);
        ndev->stats.tx_errors++;
        netif_trans_update(ndev);
        netif_wake_queue(ndev);
}

static void w5100_restart_work(struct work_struct *work)
{
        struct w5100_priv *priv = container_of(work, struct w5100_priv,
                                               restart_work);

        w5100_restart(priv->ndev);
}

static void w5100_tx_timeout(struct net_device *ndev, unsigned int txqueue)
{
        struct w5100_priv *priv = netdev_priv(ndev);

        if (priv->ops->may_sleep)
                schedule_work(&priv->restart_work);
        else
                w5100_restart(ndev);
}

static void w5100_tx_skb(struct net_device *ndev, struct sk_buff *skb)
{
        struct w5100_priv *priv = netdev_priv(ndev);
        u16 offset;

        offset = w5100_read16(priv, W5100_S0_TX_WR(priv));
        w5100_writebuf(priv, offset, skb->data, skb->len);
        w5100_write16(priv, W5100_S0_TX_WR(priv), offset + skb->len);
        ndev->stats.tx_bytes += skb->len;
        ndev->stats.tx_packets++;
        dev_kfree_skb(skb);

        w5100_command(priv, S0_CR_SEND);
}

static void w5100_tx_work(struct work_struct *work)
{
        struct w5100_priv *priv = container_of(work, struct w5100_priv,
                                               tx_work);
        struct sk_buff *skb = priv->tx_skb;

        priv->tx_skb = NULL;

        if (WARN_ON(!skb))
                return;
        w5100_tx_skb(priv->ndev, skb);
}

static netdev_tx_t w5100_start_tx(struct sk_buff *skb, struct net_device *ndev)
{
        struct w5100_priv *priv = netdev_priv(ndev);

        netif_stop_queue(ndev);

        if (priv->ops->may_sleep) {
                WARN_ON(priv->tx_skb);
                priv->tx_skb = skb;
                queue_work(priv->xfer_wq, &priv->tx_work);
        } else {
                w5100_tx_skb(ndev, skb);
        }

        return NETDEV_TX_OK;
}

static struct sk_buff *w5100_rx_skb(struct net_device *ndev)
{
        struct w5100_priv *priv = netdev_priv(ndev);
        struct sk_buff *skb;
        u16 rx_len;
        u16 offset;
        u8 header[2];
        u16 rx_buf_len = w5100_read16(priv, W5100_S0_RX_RSR(priv));

        if (rx_buf_len == 0)
                return NULL;

        offset = w5100_read16(priv, W5100_S0_RX_RD(priv));
        w5100_readbuf(priv, offset, header, 2);
        rx_len = get_unaligned_be16(header) - 2;

        skb = netdev_alloc_skb_ip_align(ndev, rx_len);
        if (unlikely(!skb)) {
                w5100_write16(priv, W5100_S0_RX_RD(priv), offset + rx_buf_len);
                w5100_command(priv, S0_CR_RECV);
                ndev->stats.rx_dropped++;
                return NULL;
        }

        skb_put(skb, rx_len);
        w5100_readbuf(priv, offset + 2, skb->data, rx_len);
        w5100_write16(priv, W5100_S0_RX_RD(priv), offset + 2 + rx_len);
        w5100_command(priv, S0_CR_RECV);
        skb->protocol = eth_type_trans(skb, ndev);

        ndev->stats.rx_packets++;
        ndev->stats.rx_bytes += rx_len;

        return skb;
}

static void w5100_rx_work(struct work_struct *work)
{
        struct w5100_priv *priv = container_of(work, struct w5100_priv,
                                               rx_work);
        struct sk_buff *skb;

        while ((skb = w5100_rx_skb(priv->ndev)))
                netif_rx(skb);

        w5100_enable_intr(priv);
}

static int w5100_napi_poll(struct napi_struct *napi, int budget)
{
        struct w5100_priv *priv = container_of(napi, struct w5100_priv, napi);
        int rx_count;

        for (rx_count = 0; rx_count < budget; rx_count++) {
                struct sk_buff *skb = w5100_rx_skb(priv->ndev);

                if (skb)
                        netif_receive_skb(skb);
                else
                        break;
        }

        if (rx_count < budget) {
                napi_complete_done(napi, rx_count);
                w5100_enable_intr(priv);
        }

        return rx_count;
}

static irqreturn_t w5100_interrupt(int irq, void *ndev_instance)
{
        struct net_device *ndev = ndev_instance;
        struct w5100_priv *priv = netdev_priv(ndev);

        int ir = w5100_read(priv, W5100_S0_IR(priv));
        if (!ir)
                return IRQ_NONE;
        w5100_write(priv, W5100_S0_IR(priv), ir);

        if (ir & S0_IR_SENDOK) {
                netif_dbg(priv, tx_done, ndev, "tx done\n");
                netif_wake_queue(ndev);
        }

        if (ir & S0_IR_RECV) {
                w5100_disable_intr(priv);

                if (priv->ops->may_sleep)
                        queue_work(priv->xfer_wq, &priv->rx_work);
                else
                        napi_schedule(&priv->napi);
        }

        return IRQ_HANDLED;
}

static void w5100_setrx_work(struct work_struct *work)
{
        struct w5100_priv *priv = container_of(work, struct w5100_priv,
                                               setrx_work);

        w5100_hw_start(priv);
}

static void w5100_set_rx_mode(struct net_device *ndev)
{
        struct w5100_priv *priv = netdev_priv(ndev);
        bool set_promisc = (ndev->flags & IFF_PROMISC) != 0;

        if (priv->promisc != set_promisc) {
                priv->promisc = set_promisc;

                if (priv->ops->may_sleep)
                        schedule_work(&priv->setrx_work);
                else
                        w5100_hw_start(priv);
        }
}

static int w5100_set_macaddr(struct net_device *ndev, void *addr)
{
        struct w5100_priv *priv = netdev_priv(ndev);
        struct sockaddr *sock_addr = addr;

        if (!is_valid_ether_addr(sock_addr->sa_data))
                return -EADDRNOTAVAIL;
        eth_hw_addr_set(ndev, sock_addr->sa_data);
        w5100_write_macaddr(priv);
        return 0;
}

static int w5100_open(struct net_device *ndev)
{
        struct w5100_priv *priv = netdev_priv(ndev);

        netif_info(priv, ifup, ndev, "enabling\n");
        w5100_hw_start(priv);
        napi_enable(&priv->napi);
        netif_start_queue(ndev);
        return 0;
}

static int w5100_stop(struct net_device *ndev)
{
        struct w5100_priv *priv = netdev_priv(ndev);

        netif_info(priv, ifdown, ndev, "shutting down\n");
        w5100_hw_close(priv);
        netif_carrier_off(ndev);
        netif_stop_queue(ndev);
        napi_disable(&priv->napi);
        return 0;
}

static const struct ethtool_ops w5100_ethtool_ops = {
        .get_drvinfo            = w5100_get_drvinfo,
        .get_msglevel           = w5100_get_msglevel,
        .set_msglevel           = w5100_set_msglevel,
        .get_regs_len           = w5100_get_regs_len,
        .get_regs               = w5100_get_regs,
};

static const struct net_device_ops w5100_netdev_ops = {
        .ndo_open               = w5100_open,
        .ndo_stop               = w5100_stop,
        .ndo_start_xmit         = w5100_start_tx,
        .ndo_tx_timeout         = w5100_tx_timeout,
        .ndo_set_rx_mode        = w5100_set_rx_mode,
        .ndo_set_mac_address    = w5100_set_macaddr,
        .ndo_validate_addr      = eth_validate_addr,
};

void *w5100_ops_priv(const struct net_device *ndev)
{
        return netdev_priv(ndev) +
               ALIGN(sizeof(struct w5100_priv), NETDEV_ALIGN);
}
EXPORT_SYMBOL_GPL(w5100_ops_priv);

int w5100_probe(struct device *dev, const struct w5100_ops *ops,
                int sizeof_ops_priv, const void *mac_addr, int irq)
{
        struct w5100_priv *priv;
        struct net_device *ndev;
        int err;
        size_t alloc_size;

        alloc_size = sizeof(*priv);
        if (sizeof_ops_priv) {
                alloc_size = ALIGN(alloc_size, NETDEV_ALIGN);
                alloc_size += sizeof_ops_priv;
        }
        alloc_size += NETDEV_ALIGN - 1;

        ndev = alloc_etherdev(alloc_size);
        if (!ndev)
                return -ENOMEM;
        SET_NETDEV_DEV(ndev, dev);
        dev_set_drvdata(dev, ndev);
        priv = netdev_priv(ndev);

        switch (ops->chip_id) {
        case W5100:
                priv->s0_regs = W5100_S0_REGS;
                priv->s0_tx_buf = W5100_TX_MEM_START;
                priv->s0_tx_buf_size = W5100_TX_MEM_SIZE;
                priv->s0_rx_buf = W5100_RX_MEM_START;
                priv->s0_rx_buf_size = W5100_RX_MEM_SIZE;
                break;
        case W5200:
                priv->s0_regs = W5200_S0_REGS;
                priv->s0_tx_buf = W5200_TX_MEM_START;
                priv->s0_tx_buf_size = W5200_TX_MEM_SIZE;
                priv->s0_rx_buf = W5200_RX_MEM_START;
                priv->s0_rx_buf_size = W5200_RX_MEM_SIZE;
                break;
        case W5500:
                priv->s0_regs = W5500_S0_REGS;
                priv->s0_tx_buf = W5500_TX_MEM_START;
                priv->s0_tx_buf_size = W5500_TX_MEM_SIZE;
                priv->s0_rx_buf = W5500_RX_MEM_START;
                priv->s0_rx_buf_size = W5500_RX_MEM_SIZE;
                break;
        default:
                err = -EINVAL;
                goto err_register;
        }

        priv->ndev = ndev;
        priv->ops = ops;
        priv->irq = irq;

        ndev->netdev_ops = &w5100_netdev_ops;
        ndev->ethtool_ops = &w5100_ethtool_ops;
        netif_napi_add_weight(ndev, &priv->napi, w5100_napi_poll, 16);

        /* This chip doesn't support VLAN packets with normal MTU,
         * so disable VLAN for this device.
         */
        ndev->features |= NETIF_F_VLAN_CHALLENGED;

        err = register_netdev(ndev);
        if (err < 0)
                goto err_register;

        priv->xfer_wq = alloc_workqueue("%s", WQ_MEM_RECLAIM | WQ_PERCPU, 0,
                                        netdev_name(ndev));
        if (!priv->xfer_wq) {
                err = -ENOMEM;
                goto err_wq;
        }

        INIT_WORK(&priv->rx_work, w5100_rx_work);
        INIT_WORK(&priv->tx_work, w5100_tx_work);
        INIT_WORK(&priv->setrx_work, w5100_setrx_work);
        INIT_WORK(&priv->restart_work, w5100_restart_work);

        if (mac_addr)
                eth_hw_addr_set(ndev, mac_addr);
        else
                eth_hw_addr_random(ndev);

        if (priv->ops->init) {
                err = priv->ops->init(priv->ndev);
                if (err)
                        goto err_hw;
        }

        err = w5100_hw_reset(priv);
        if (err)
                goto err_hw;

        if (ops->may_sleep) {
                err = request_threaded_irq(priv->irq, NULL, w5100_interrupt,
                                           IRQF_TRIGGER_LOW | IRQF_ONESHOT,
                                           netdev_name(ndev), ndev);
        } else {
                err = request_irq(priv->irq, w5100_interrupt,
                                  IRQF_TRIGGER_LOW, netdev_name(ndev), ndev);
        }
        if (err)
                goto err_hw;

        return 0;

err_hw:
        destroy_workqueue(priv->xfer_wq);
err_wq:
        unregister_netdev(ndev);
err_register:
        free_netdev(ndev);
        return err;
}
EXPORT_SYMBOL_GPL(w5100_probe);

void w5100_remove(struct device *dev)
{
        struct net_device *ndev = dev_get_drvdata(dev);
        struct w5100_priv *priv = netdev_priv(ndev);

        w5100_hw_reset(priv);
        free_irq(priv->irq, ndev);

        flush_work(&priv->setrx_work);
        flush_work(&priv->restart_work);
        destroy_workqueue(priv->xfer_wq);

        unregister_netdev(ndev);
        free_netdev(ndev);
}
EXPORT_SYMBOL_GPL(w5100_remove);

#ifdef CONFIG_PM_SLEEP
static int w5100_suspend(struct device *dev)
{
        struct net_device *ndev = dev_get_drvdata(dev);
        struct w5100_priv *priv = netdev_priv(ndev);

        if (netif_running(ndev)) {
                netif_carrier_off(ndev);
                netif_device_detach(ndev);

                w5100_hw_close(priv);
        }
        return 0;
}

static int w5100_resume(struct device *dev)
{
        struct net_device *ndev = dev_get_drvdata(dev);
        struct w5100_priv *priv = netdev_priv(ndev);

        if (netif_running(ndev)) {
                w5100_hw_reset(priv);
                w5100_hw_start(priv);

                netif_device_attach(ndev);
        }
        return 0;
}
#endif /* CONFIG_PM_SLEEP */

SIMPLE_DEV_PM_OPS(w5100_pm_ops, w5100_suspend, w5100_resume);
EXPORT_SYMBOL_GPL(w5100_pm_ops);