/*
 * smc91x.c
 * This is a driver for SMSC's 91C9x/91C1xx single-chip Ethernet devices.
 *
 * Copyright (C) 1996 by Erik Stahlman
 * Copyright (C) 2001 Standard Microsystems Corporation
 *      Developed by Simple Network Magic Corporation
 * Copyright (C) 2003 Monta Vista Software, Inc.
 *      Unified SMC91x driver by Nicolas Pitre
 *
 * 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, see <http://www.gnu.org/licenses/>.
 *
 * Arguments:
 *      io      = for the base address
 *      irq     = for the IRQ
 *      nowait  = 0 for normal wait states, 1 eliminates additional wait states
 *
 * original author:
 *      Erik Stahlman <erik@vt.edu>
 *
 * hardware multicast code:
 *    Peter Cammaert <pc@denkart.be>
 *
 * contributors:
 *      Daris A Nevil <dnevil@snmc.com>
 *      Nicolas Pitre <nico@fluxnic.net>
 *      Russell King <rmk@arm.linux.org.uk>
 *
 * History:
 *   08/20/00  Arnaldo Melo       fix kfree(skb) in smc_hardware_send_packet
 *   12/15/00  Christian Jullien  fix "Warning: kfree_skb on hard IRQ"
 *   03/16/01  Daris A Nevil      modified smc9194.c for use with LAN91C111
 *   08/22/01  Scott Anderson     merge changes from smc9194 to smc91111
 *   08/21/01  Pramod B Bhardwaj  added support for RevB of LAN91C111
 *   12/20/01  Jeff Sutherland    initial port to Xscale PXA with DMA support
 *   04/07/03  Nicolas Pitre      unified SMC91x driver, killed irq races,
 *                                more bus abstraction, big cleanup, etc.
 *   29/09/03  Russell King       - add driver model support
 *                                - ethtool support
 *                                - convert to use generic MII interface
 *                                - add link up/down notification
 *                                - don't try to handle full negotiation in
 *                                  smc_phy_configure
 *                                - clean up (and fix stack overrun) in PHY
 *                                  MII read/write functions
 *   22/09/04  Nicolas Pitre      big update (see commit log for details)
 */
static const char version[] =
        "smc91x.c: v1.1, sep 22 2004 by Nicolas Pitre <nico@fluxnic.net>";

/* Debugging level */
#ifndef SMC_DEBUG
#define SMC_DEBUG               0
#endif


#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/errno.h>
#include <linux/ioport.h>
#include <linux/crc32.h>
#include <linux/platform_device.h>
#include <linux/spinlock.h>
#include <linux/ethtool.h>
#include <linux/mii.h>
#include <linux/workqueue.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/of_gpio.h>

#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/skbuff.h>

#include <asm/io.h>

#include "smc91x.h"

#if defined(CONFIG_ASSABET_NEPONSET)
#include <mach/assabet.h>
#include <mach/neponset.h>
#endif

#ifndef SMC_NOWAIT
# define SMC_NOWAIT             0
#endif
static int nowait = SMC_NOWAIT;
module_param(nowait, int, 0400);
MODULE_PARM_DESC(nowait, "set to 1 for no wait state");

/*
 * Transmit timeout, default 5 seconds.
 */
static int watchdog = 1000;
module_param(watchdog, int, 0400);
MODULE_PARM_DESC(watchdog, "transmit timeout in milliseconds");

MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:smc91x");

/*
 * The internal workings of the driver.  If you are changing anything
 * here with the SMC stuff, you should have the datasheet and know
 * what you are doing.
 */
#define CARDNAME "smc91x"

/*
 * Use power-down feature of the chip
 */
#define POWER_DOWN              1

/*
 * Wait time for memory to be free.  This probably shouldn't be
 * tuned that much, as waiting for this means nothing else happens
 * in the system
 */
#define MEMORY_WAIT_TIME        16

/*
 * The maximum number of processing loops allowed for each call to the
 * IRQ handler.
 */
#define MAX_IRQ_LOOPS           8

/*
 * This selects whether TX packets are sent one by one to the SMC91x internal
 * memory and throttled until transmission completes.  This may prevent
 * RX overruns a litle by keeping much of the memory free for RX packets
 * but to the expense of reduced TX throughput and increased IRQ overhead.
 * Note this is not a cure for a too slow data bus or too high IRQ latency.
 */
#define THROTTLE_TX_PKTS        0

/*
 * The MII clock high/low times.  2x this number gives the MII clock period
 * in microseconds. (was 50, but this gives 6.4ms for each MII transaction!)
 */
#define MII_DELAY               1

#define DBG(n, dev, fmt, ...)                                   \
        do {                                                    \
                if (SMC_DEBUG >= (n))                           \
                        netdev_dbg(dev, fmt, ##__VA_ARGS__);    \
        } while (0)

#define PRINTK(dev, fmt, ...)                                   \
        do {                                                    \
                if (SMC_DEBUG > 0)                              \
                        netdev_info(dev, fmt, ##__VA_ARGS__);   \
                else                                            \
                        netdev_dbg(dev, fmt, ##__VA_ARGS__);    \
        } while (0)

#if SMC_DEBUG > 3
static void PRINT_PKT(u_char *buf, int length)
{
        int i;
        int remainder;
        int lines;

        lines = length / 16;
        remainder = length % 16;

        for (i = 0; i < lines ; i ++) {
                int cur;
                printk(KERN_DEBUG);
                for (cur = 0; cur < 8; cur++) {
                        u_char a, b;
                        a = *buf++;
                        b = *buf++;
                        pr_cont("%02x%02x ", a, b);
                }
                pr_cont("\n");
        }
        printk(KERN_DEBUG);
        for (i = 0; i < remainder/2 ; i++) {
                u_char a, b;
                a = *buf++;
                b = *buf++;
                pr_cont("%02x%02x ", a, b);
        }
        pr_cont("\n");
}
#else
static inline void PRINT_PKT(u_char *buf, int length) { }
#endif


/* this enables an interrupt in the interrupt mask register */
#define SMC_ENABLE_INT(lp, x) do {                                      \
        unsigned char mask;                                             \
        unsigned long smc_enable_flags;                                 \
        spin_lock_irqsave(&lp->lock, smc_enable_flags);                 \
        mask = SMC_GET_INT_MASK(lp);                                    \
        mask |= (x);                                                    \
        SMC_SET_INT_MASK(lp, mask);                                     \
        spin_unlock_irqrestore(&lp->lock, smc_enable_flags);            \
} while (0)

/* this disables an interrupt from the interrupt mask register */
#define SMC_DISABLE_INT(lp, x) do {                                     \
        unsigned char mask;                                             \
        unsigned long smc_disable_flags;                                \
        spin_lock_irqsave(&lp->lock, smc_disable_flags);                \
        mask = SMC_GET_INT_MASK(lp);                                    \
        mask &= ~(x);                                                   \
        SMC_SET_INT_MASK(lp, mask);                                     \
        spin_unlock_irqrestore(&lp->lock, smc_disable_flags);           \
} while (0)

/*
 * Wait while MMU is busy.  This is usually in the order of a few nanosecs
 * if at all, but let's avoid deadlocking the system if the hardware
 * decides to go south.
 */
#define SMC_WAIT_MMU_BUSY(lp) do {                                      \
        if (unlikely(SMC_GET_MMU_CMD(lp) & MC_BUSY)) {          \
                unsigned long timeout = jiffies + 2;                    \
                while (SMC_GET_MMU_CMD(lp) & MC_BUSY) {         \
                        if (time_after(jiffies, timeout)) {             \
                                netdev_dbg(dev, "timeout %s line %d\n", \
                                           __FILE__, __LINE__);         \
                                break;                                  \
                        }                                               \
                        cpu_relax();                                    \
                }                                                       \
        }                                                               \
} while (0)


/*
 * this does a soft reset on the device
 */
static void smc_reset(struct net_device *dev)
{
        struct smc_local *lp = netdev_priv(dev);
        void __iomem *ioaddr = lp->base;
        unsigned int ctl, cfg;
        struct sk_buff *pending_skb;

        DBG(2, dev, "%s\n", __func__);

        /* Disable all interrupts, block TX tasklet */
        spin_lock_irq(&lp->lock);
        SMC_SELECT_BANK(lp, 2);
        SMC_SET_INT_MASK(lp, 0);
        pending_skb = lp->pending_tx_skb;
        lp->pending_tx_skb = NULL;
        spin_unlock_irq(&lp->lock);

        /* free any pending tx skb */
        if (pending_skb) {
                dev_kfree_skb(pending_skb);
                dev->stats.tx_errors++;
                dev->stats.tx_aborted_errors++;
        }

        /*
         * This resets the registers mostly to defaults, but doesn't
         * affect EEPROM.  That seems unnecessary
         */
        SMC_SELECT_BANK(lp, 0);
        SMC_SET_RCR(lp, RCR_SOFTRST);

        /*
         * Setup the Configuration Register
         * This is necessary because the CONFIG_REG is not affected
         * by a soft reset
         */
        SMC_SELECT_BANK(lp, 1);

        cfg = CONFIG_DEFAULT;

        /*
         * Setup for fast accesses if requested.  If the card/system
         * can't handle it then there will be no recovery except for
         * a hard reset or power cycle
         */
        if (lp->cfg.flags & SMC91X_NOWAIT)
                cfg |= CONFIG_NO_WAIT;

        /*
         * Release from possible power-down state
         * Configuration register is not affected by Soft Reset
         */
        cfg |= CONFIG_EPH_POWER_EN;

        SMC_SET_CONFIG(lp, cfg);

        /* this should pause enough for the chip to be happy */
        /*
         * elaborate?  What does the chip _need_? --jgarzik
         *
         * This seems to be undocumented, but something the original
         * driver(s) have always done.  Suspect undocumented timing
         * info/determined empirically. --rmk
         */
        udelay(1);

        /* Disable transmit and receive functionality */
        SMC_SELECT_BANK(lp, 0);
        SMC_SET_RCR(lp, RCR_CLEAR);
        SMC_SET_TCR(lp, TCR_CLEAR);

        SMC_SELECT_BANK(lp, 1);
        ctl = SMC_GET_CTL(lp) | CTL_LE_ENABLE;

        /*
         * Set the control register to automatically release successfully
         * transmitted packets, to make the best use out of our limited
         * memory
         */
        if(!THROTTLE_TX_PKTS)
                ctl |= CTL_AUTO_RELEASE;
        else
                ctl &= ~CTL_AUTO_RELEASE;
        SMC_SET_CTL(lp, ctl);

        /* Reset the MMU */
        SMC_SELECT_BANK(lp, 2);
        SMC_SET_MMU_CMD(lp, MC_RESET);
        SMC_WAIT_MMU_BUSY(lp);
}

/*
 * Enable Interrupts, Receive, and Transmit
 */
static void smc_enable(struct net_device *dev)
{
        struct smc_local *lp = netdev_priv(dev);
        void __iomem *ioaddr = lp->base;
        int mask;

        DBG(2, dev, "%s\n", __func__);

        /* see the header file for options in TCR/RCR DEFAULT */
        SMC_SELECT_BANK(lp, 0);
        SMC_SET_TCR(lp, lp->tcr_cur_mode);
        SMC_SET_RCR(lp, lp->rcr_cur_mode);

        SMC_SELECT_BANK(lp, 1);
        SMC_SET_MAC_ADDR(lp, dev->dev_addr);

        /* now, enable interrupts */
        mask = IM_EPH_INT|IM_RX_OVRN_INT|IM_RCV_INT;
        if (lp->version >= (CHIP_91100 << 4))
                mask |= IM_MDINT;
        SMC_SELECT_BANK(lp, 2);
        SMC_SET_INT_MASK(lp, mask);

        /*
         * From this point the register bank must _NOT_ be switched away
         * to something else than bank 2 without proper locking against
         * races with any tasklet or interrupt handlers until smc_shutdown()
         * or smc_reset() is called.
         */
}

/*
 * this puts the device in an inactive state
 */
static void smc_shutdown(struct net_device *dev)
{
        struct smc_local *lp = netdev_priv(dev);
        void __iomem *ioaddr = lp->base;
        struct sk_buff *pending_skb;

        DBG(2, dev, "%s: %s\n", CARDNAME, __func__);

        /* no more interrupts for me */
        spin_lock_irq(&lp->lock);
        SMC_SELECT_BANK(lp, 2);
        SMC_SET_INT_MASK(lp, 0);
        pending_skb = lp->pending_tx_skb;
        lp->pending_tx_skb = NULL;
        spin_unlock_irq(&lp->lock);
        if (pending_skb)
                dev_kfree_skb(pending_skb);

        /* and tell the card to stay away from that nasty outside world */
        SMC_SELECT_BANK(lp, 0);
        SMC_SET_RCR(lp, RCR_CLEAR);
        SMC_SET_TCR(lp, TCR_CLEAR);

#ifdef POWER_DOWN
        /* finally, shut the chip down */
        SMC_SELECT_BANK(lp, 1);
        SMC_SET_CONFIG(lp, SMC_GET_CONFIG(lp) & ~CONFIG_EPH_POWER_EN);
#endif
}

/*
 * This is the procedure to handle the receipt of a packet.
 */
static inline void  smc_rcv(struct net_device *dev)
{
        struct smc_local *lp = netdev_priv(dev);
        void __iomem *ioaddr = lp->base;
        unsigned int packet_number, status, packet_len;

        DBG(3, dev, "%s\n", __func__);

        packet_number = SMC_GET_RXFIFO(lp);
        if (unlikely(packet_number & RXFIFO_REMPTY)) {
                PRINTK(dev, "smc_rcv with nothing on FIFO.\n");
                return;
        }

        /* read from start of packet */
        SMC_SET_PTR(lp, PTR_READ | PTR_RCV | PTR_AUTOINC);

        /* First two words are status and packet length */
        SMC_GET_PKT_HDR(lp, status, packet_len);
        packet_len &= 0x07ff;  /* mask off top bits */
        DBG(2, dev, "RX PNR 0x%x STATUS 0x%04x LENGTH 0x%04x (%d)\n",
            packet_number, status, packet_len, packet_len);

        back:
        if (unlikely(packet_len < 6 || status & RS_ERRORS)) {
                if (status & RS_TOOLONG && packet_len <= (1514 + 4 + 6)) {
                        /* accept VLAN packets */
                        status &= ~RS_TOOLONG;
                        goto back;
                }
                if (packet_len < 6) {
                        /* bloody hardware */
                        netdev_err(dev, "fubar (rxlen %u status %x\n",
                                   packet_len, status);
                        status |= RS_TOOSHORT;
                }
                SMC_WAIT_MMU_BUSY(lp);
                SMC_SET_MMU_CMD(lp, MC_RELEASE);
                dev->stats.rx_errors++;
                if (status & RS_ALGNERR)
                        dev->stats.rx_frame_errors++;
                if (status & (RS_TOOSHORT | RS_TOOLONG))
                        dev->stats.rx_length_errors++;
                if (status & RS_BADCRC)
                        dev->stats.rx_crc_errors++;
        } else {
                struct sk_buff *skb;
                unsigned char *data;
                unsigned int data_len;

                /* set multicast stats */
                if (status & RS_MULTICAST)
                        dev->stats.multicast++;

                /*
                 * Actual payload is packet_len - 6 (or 5 if odd byte).
                 * We want skb_reserve(2) and the final ctrl word
                 * (2 bytes, possibly containing the payload odd byte).
                 * Furthermore, we add 2 bytes to allow rounding up to
                 * multiple of 4 bytes on 32 bit buses.
                 * Hence packet_len - 6 + 2 + 2 + 2.
                 */
                skb = netdev_alloc_skb(dev, packet_len);
                if (unlikely(skb == NULL)) {
                        SMC_WAIT_MMU_BUSY(lp);
                        SMC_SET_MMU_CMD(lp, MC_RELEASE);
                        dev->stats.rx_dropped++;
                        return;
                }

                /* Align IP header to 32 bits */
                skb_reserve(skb, 2);

                /* BUG: the LAN91C111 rev A never sets this bit. Force it. */
                if (lp->version == 0x90)
                        status |= RS_ODDFRAME;

                /*
                 * If odd length: packet_len - 5,
                 * otherwise packet_len - 6.
                 * With the trailing ctrl byte it's packet_len - 4.
                 */
                data_len = packet_len - ((status & RS_ODDFRAME) ? 5 : 6);
                data = skb_put(skb, data_len);
                SMC_PULL_DATA(lp, data, packet_len - 4);

                SMC_WAIT_MMU_BUSY(lp);
                SMC_SET_MMU_CMD(lp, MC_RELEASE);

                PRINT_PKT(data, packet_len - 4);

                skb->protocol = eth_type_trans(skb, dev);
                netif_rx(skb);
                dev->stats.rx_packets++;
                dev->stats.rx_bytes += data_len;
        }
}

#ifdef CONFIG_SMP
/*
 * On SMP we have the following problem:
 *
 *      A = smc_hardware_send_pkt()
 *      B = smc_hard_start_xmit()
 *      C = smc_interrupt()
 *
 * A and B can never be executed simultaneously.  However, at least on UP,
 * it is possible (and even desirable) for C to interrupt execution of
 * A or B in order to have better RX reliability and avoid overruns.
 * C, just like A and B, must have exclusive access to the chip and
 * each of them must lock against any other concurrent access.
 * Unfortunately this is not possible to have C suspend execution of A or
 * B taking place on another CPU. On UP this is no an issue since A and B
 * are run from softirq context and C from hard IRQ context, and there is
 * no other CPU where concurrent access can happen.
 * If ever there is a way to force at least B and C to always be executed
 * on the same CPU then we could use read/write locks to protect against
 * any other concurrent access and C would always interrupt B. But life
 * isn't that easy in a SMP world...
 */
#define smc_special_trylock(lock, flags)                                \
({                                                                      \
        int __ret;                                                      \
        local_irq_save(flags);                                          \
        __ret = spin_trylock(lock);                                     \
        if (!__ret)                                                     \
                local_irq_restore(flags);                               \
        __ret;                                                          \
})
#define smc_special_lock(lock, flags)           spin_lock_irqsave(lock, flags)
#define smc_special_unlock(lock, flags)         spin_unlock_irqrestore(lock, flags)
#else
#define smc_special_trylock(lock, flags)        ((void)flags, true)
#define smc_special_lock(lock, flags)           do { flags = 0; } while (0)
#define smc_special_unlock(lock, flags) do { flags = 0; } while (0)
#endif

/*
 * This is called to actually send a packet to the chip.
 */
static void smc_hardware_send_pkt(unsigned long data)
{
        struct net_device *dev = (struct net_device *)data;
        struct smc_local *lp = netdev_priv(dev);
        void __iomem *ioaddr = lp->base;
        struct sk_buff *skb;
        unsigned int packet_no, len;
        unsigned char *buf;
        unsigned long flags;

        DBG(3, dev, "%s\n", __func__);

        if (!smc_special_trylock(&lp->lock, flags)) {
                netif_stop_queue(dev);
                tasklet_schedule(&lp->tx_task);
                return;
        }

        skb = lp->pending_tx_skb;
        if (unlikely(!skb)) {
                smc_special_unlock(&lp->lock, flags);
                return;
        }
        lp->pending_tx_skb = NULL;

        packet_no = SMC_GET_AR(lp);
        if (unlikely(packet_no & AR_FAILED)) {
                netdev_err(dev, "Memory allocation failed.\n");
                dev->stats.tx_errors++;
                dev->stats.tx_fifo_errors++;
                smc_special_unlock(&lp->lock, flags);
                goto done;
        }

        /* point to the beginning of the packet */
        SMC_SET_PN(lp, packet_no);
        SMC_SET_PTR(lp, PTR_AUTOINC);

        buf = skb->data;
        len = skb->len;
        DBG(2, dev, "TX PNR 0x%x LENGTH 0x%04x (%d) BUF 0x%p\n",
            packet_no, len, len, buf);
        PRINT_PKT(buf, len);

        /*
         * Send the packet length (+6 for status words, length, and ctl.
         * The card will pad to 64 bytes with zeroes if packet is too small.
         */
        SMC_PUT_PKT_HDR(lp, 0, len + 6);

        /* send the actual data */
        SMC_PUSH_DATA(lp, buf, len & ~1);

        /* Send final ctl word with the last byte if there is one */
        SMC_outw(lp, ((len & 1) ? (0x2000 | buf[len - 1]) : 0), ioaddr,
                 DATA_REG(lp));

        /*
         * If THROTTLE_TX_PKTS is set, we stop the queue here. This will
         * have the effect of having at most one packet queued for TX
         * in the chip's memory at all time.
         *
         * If THROTTLE_TX_PKTS is not set then the queue is stopped only
         * when memory allocation (MC_ALLOC) does not succeed right away.
         */
        if (THROTTLE_TX_PKTS)
                netif_stop_queue(dev);

        /* queue the packet for TX */
        SMC_SET_MMU_CMD(lp, MC_ENQUEUE);
        smc_special_unlock(&lp->lock, flags);

        netif_trans_update(dev);
        dev->stats.tx_packets++;
        dev->stats.tx_bytes += len;

        SMC_ENABLE_INT(lp, IM_TX_INT | IM_TX_EMPTY_INT);

done:   if (!THROTTLE_TX_PKTS)
                netif_wake_queue(dev);

        dev_consume_skb_any(skb);
}

/*
 * Since I am not sure if I will have enough room in the chip's ram
 * to store the packet, I call this routine which either sends it
 * now, or set the card to generates an interrupt when ready
 * for the packet.
 */
static int smc_hard_start_xmit(struct sk_buff *skb, struct net_device *dev)
{
        struct smc_local *lp = netdev_priv(dev);
        void __iomem *ioaddr = lp->base;
        unsigned int numPages, poll_count, status;
        unsigned long flags;

        DBG(3, dev, "%s\n", __func__);

        BUG_ON(lp->pending_tx_skb != NULL);

        /*
         * The MMU wants the number of pages to be the number of 256 bytes
         * 'pages', minus 1 (since a packet can't ever have 0 pages :))
         *
         * The 91C111 ignores the size bits, but earlier models don't.
         *
         * Pkt size for allocating is data length +6 (for additional status
         * words, length and ctl)
         *
         * If odd size then last byte is included in ctl word.
         */
        numPages = ((skb->len & ~1) + (6 - 1)) >> 8;
        if (unlikely(numPages > 7)) {
                netdev_warn(dev, "Far too big packet error.\n");
                dev->stats.tx_errors++;
                dev->stats.tx_dropped++;
                dev_kfree_skb_any(skb);
                return NETDEV_TX_OK;
        }

        smc_special_lock(&lp->lock, flags);

        /* now, try to allocate the memory */
        SMC_SET_MMU_CMD(lp, MC_ALLOC | numPages);

        /*
         * Poll the chip for a short amount of time in case the
         * allocation succeeds quickly.
         */
        poll_count = MEMORY_WAIT_TIME;
        do {
                status = SMC_GET_INT(lp);
                if (status & IM_ALLOC_INT) {
                        SMC_ACK_INT(lp, IM_ALLOC_INT);
                        break;
                }
        } while (--poll_count);

        smc_special_unlock(&lp->lock, flags);

        lp->pending_tx_skb = skb;
        if (!poll_count) {
                /* oh well, wait until the chip finds memory later */
                netif_stop_queue(dev);
                DBG(2, dev, "TX memory allocation deferred.\n");
                SMC_ENABLE_INT(lp, IM_ALLOC_INT);
        } else {
                /*
                 * Allocation succeeded: push packet to the chip's own memory
                 * immediately.
                 */
                smc_hardware_send_pkt((unsigned long)dev);
        }

        return NETDEV_TX_OK;
}

/*
 * This handles a TX interrupt, which is only called when:
 * - a TX error occurred, or
 * - CTL_AUTO_RELEASE is not set and TX of a packet completed.
 */
static void smc_tx(struct net_device *dev)
{
        struct smc_local *lp = netdev_priv(dev);
        void __iomem *ioaddr = lp->base;
        unsigned int saved_packet, packet_no, tx_status, pkt_len;

        DBG(3, dev, "%s\n", __func__);

        /* If the TX FIFO is empty then nothing to do */
        packet_no = SMC_GET_TXFIFO(lp);
        if (unlikely(packet_no & TXFIFO_TEMPTY)) {
                PRINTK(dev, "smc_tx with nothing on FIFO.\n");
                return;
        }

        /* select packet to read from */
        saved_packet = SMC_GET_PN(lp);
        SMC_SET_PN(lp, packet_no);

        /* read the first word (status word) from this packet */
        SMC_SET_PTR(lp, PTR_AUTOINC | PTR_READ);
        SMC_GET_PKT_HDR(lp, tx_status, pkt_len);
        DBG(2, dev, "TX STATUS 0x%04x PNR 0x%02x\n",
            tx_status, packet_no);

        if (!(tx_status & ES_TX_SUC))
                dev->stats.tx_errors++;

        if (tx_status & ES_LOSTCARR)
                dev->stats.tx_carrier_errors++;

        if (tx_status & (ES_LATCOL | ES_16COL)) {
                PRINTK(dev, "%s occurred on last xmit\n",
                       (tx_status & ES_LATCOL) ?
                        "late collision" : "too many collisions");
                dev->stats.tx_window_errors++;
                if (!(dev->stats.tx_window_errors & 63) && net_ratelimit()) {
                        netdev_info(dev, "unexpectedly large number of bad collisions. Please check duplex setting.\n");
                }
        }

        /* kill the packet */
        SMC_WAIT_MMU_BUSY(lp);
        SMC_SET_MMU_CMD(lp, MC_FREEPKT);

        /* Don't restore Packet Number Reg until busy bit is cleared */
        SMC_WAIT_MMU_BUSY(lp);
        SMC_SET_PN(lp, saved_packet);

        /* re-enable transmit */
        SMC_SELECT_BANK(lp, 0);
        SMC_SET_TCR(lp, lp->tcr_cur_mode);
        SMC_SELECT_BANK(lp, 2);
}


/*---PHY CONTROL AND CONFIGURATION-----------------------------------------*/

static void smc_mii_out(struct net_device *dev, unsigned int val, int bits)
{
        struct smc_local *lp = netdev_priv(dev);
        void __iomem *ioaddr = lp->base;
        unsigned int mii_reg, mask;

        mii_reg = SMC_GET_MII(lp) & ~(MII_MCLK | MII_MDOE | MII_MDO);
        mii_reg |= MII_MDOE;

        for (mask = 1 << (bits - 1); mask; mask >>= 1) {
                if (val & mask)
                        mii_reg |= MII_MDO;
                else
                        mii_reg &= ~MII_MDO;

                SMC_SET_MII(lp, mii_reg);
                udelay(MII_DELAY);
                SMC_SET_MII(lp, mii_reg | MII_MCLK);
                udelay(MII_DELAY);
        }
}

static unsigned int smc_mii_in(struct net_device *dev, int bits)
{
        struct smc_local *lp = netdev_priv(dev);
        void __iomem *ioaddr = lp->base;
        unsigned int mii_reg, mask, val;

        mii_reg = SMC_GET_MII(lp) & ~(MII_MCLK | MII_MDOE | MII_MDO);
        SMC_SET_MII(lp, mii_reg);

        for (mask = 1 << (bits - 1), val = 0; mask; mask >>= 1) {
                if (SMC_GET_MII(lp) & MII_MDI)
                        val |= mask;

                SMC_SET_MII(lp, mii_reg);
                udelay(MII_DELAY);
                SMC_SET_MII(lp, mii_reg | MII_MCLK);
                udelay(MII_DELAY);
        }

        return val;
}

/*
 * Reads a register from the MII Management serial interface
 */
static int smc_phy_read(struct net_device *dev, int phyaddr, int phyreg)
{
        struct smc_local *lp = netdev_priv(dev);
        void __iomem *ioaddr = lp->base;
        unsigned int phydata;

        SMC_SELECT_BANK(lp, 3);

        /* Idle - 32 ones */
        smc_mii_out(dev, 0xffffffff, 32);

        /* Start code (01) + read (10) + phyaddr + phyreg */
        smc_mii_out(dev, 6 << 10 | phyaddr << 5 | phyreg, 14);

        /* Turnaround (2bits) + phydata */
        phydata = smc_mii_in(dev, 18);

        /* Return to idle state */
        SMC_SET_MII(lp, SMC_GET_MII(lp) & ~(MII_MCLK|MII_MDOE|MII_MDO));

        DBG(3, dev, "%s: phyaddr=0x%x, phyreg=0x%x, phydata=0x%x\n",
            __func__, phyaddr, phyreg, phydata);

        SMC_SELECT_BANK(lp, 2);
        return phydata;
}

/*
 * Writes a register to the MII Management serial interface
 */
static void smc_phy_write(struct net_device *dev, int phyaddr, int phyreg,
                          int phydata)
{
        struct smc_local *lp = netdev_priv(dev);
        void __iomem *ioaddr = lp->base;

        SMC_SELECT_BANK(lp, 3);

        /* Idle - 32 ones */
        smc_mii_out(dev, 0xffffffff, 32);

        /* Start code (01) + write (01) + phyaddr + phyreg + turnaround + phydata */
        smc_mii_out(dev, 5 << 28 | phyaddr << 23 | phyreg << 18 | 2 << 16 | phydata, 32);

        /* Return to idle state */
        SMC_SET_MII(lp, SMC_GET_MII(lp) & ~(MII_MCLK|MII_MDOE|MII_MDO));

        DBG(3, dev, "%s: phyaddr=0x%x, phyreg=0x%x, phydata=0x%x\n",
            __func__, phyaddr, phyreg, phydata);

        SMC_SELECT_BANK(lp, 2);
}

/*
 * Finds and reports the PHY address
 */
static void smc_phy_detect(struct net_device *dev)
{
        struct smc_local *lp = netdev_priv(dev);
        int phyaddr;

        DBG(2, dev, "%s\n", __func__);

        lp->phy_type = 0;

        /*
         * Scan all 32 PHY addresses if necessary, starting at
         * PHY#1 to PHY#31, and then PHY#0 last.
         */
        for (phyaddr = 1; phyaddr < 33; ++phyaddr) {
                unsigned int id1, id2;

                /* Read the PHY identifiers */
                id1 = smc_phy_read(dev, phyaddr & 31, MII_PHYSID1);
                id2 = smc_phy_read(dev, phyaddr & 31, MII_PHYSID2);

                DBG(3, dev, "phy_id1=0x%x, phy_id2=0x%x\n",
                    id1, id2);

                /* Make sure it is a valid identifier */
                if (id1 != 0x0000 && id1 != 0xffff && id1 != 0x8000 &&
                    id2 != 0x0000 && id2 != 0xffff && id2 != 0x8000) {
                        /* Save the PHY's address */
                        lp->mii.phy_id = phyaddr & 31;
                        lp->phy_type = id1 << 16 | id2;
                        break;
                }
        }
}

/*
 * Sets the PHY to a configuration as determined by the user
 */
static int smc_phy_fixed(struct net_device *dev)
{
        struct smc_local *lp = netdev_priv(dev);
        void __iomem *ioaddr = lp->base;
        int phyaddr = lp->mii.phy_id;
        int bmcr, cfg1;

        DBG(3, dev, "%s\n", __func__);

        /* Enter Link Disable state */
        cfg1 = smc_phy_read(dev, phyaddr, PHY_CFG1_REG);
        cfg1 |= PHY_CFG1_LNKDIS;
        smc_phy_write(dev, phyaddr, PHY_CFG1_REG, cfg1);

        /*
         * Set our fixed capabilities
         * Disable auto-negotiation
         */
        bmcr = 0;

        if (lp->ctl_rfduplx)
                bmcr |= BMCR_FULLDPLX;

        if (lp->ctl_rspeed == 100)
                bmcr |= BMCR_SPEED100;

        /* Write our capabilities to the phy control register */
        smc_phy_write(dev, phyaddr, MII_BMCR, bmcr);

        /* Re-Configure the Receive/Phy Control register */
        SMC_SELECT_BANK(lp, 0);
        SMC_SET_RPC(lp, lp->rpc_cur_mode);
        SMC_SELECT_BANK(lp, 2);

        return 1;
}

/**
 * smc_phy_reset - reset the phy
 * @dev: net device
 * @phy: phy address
 *
 * Issue a software reset for the specified PHY and
 * wait up to 100ms for the reset to complete.  We should
 * not access the PHY for 50ms after issuing the reset.
 *
 * The time to wait appears to be dependent on the PHY.
 *
 * Must be called with lp->lock locked.
 */
static int smc_phy_reset(struct net_device *dev, int phy)
{
        struct smc_local *lp = netdev_priv(dev);
        unsigned int bmcr;
        int timeout;

        smc_phy_write(dev, phy, MII_BMCR, BMCR_RESET);

        for (timeout = 2; timeout; timeout--) {
                spin_unlock_irq(&lp->lock);
                msleep(50);
                spin_lock_irq(&lp->lock);

                bmcr = smc_phy_read(dev, phy, MII_BMCR);
                if (!(bmcr & BMCR_RESET))
                        break;
        }

        return bmcr & BMCR_RESET;
}

/**
 * smc_phy_powerdown - powerdown phy
 * @dev: net device
 *
 * Power down the specified PHY
 */
static void smc_phy_powerdown(struct net_device *dev)
{
        struct smc_local *lp = netdev_priv(dev);
        unsigned int bmcr;
        int phy = lp->mii.phy_id;

        if (lp->phy_type == 0)
                return;

        /* We need to ensure that no calls to smc_phy_configure are
           pending.
        */

        cancel_work_sync(&lp->phy_configure);

        bmcr = smc_phy_read(dev, phy, MII_BMCR);
        smc_phy_write(dev, phy, MII_BMCR, bmcr | BMCR_PDOWN);
}

/**
 * smc_phy_check_media - check the media status and adjust TCR
 * @dev: net device
 * @init: set true for initialisation
 *
 * Select duplex mode depending on negotiation state.  This
 * also updates our carrier state.
 */
static void smc_phy_check_media(struct net_device *dev, int init)
{
        struct smc_local *lp = netdev_priv(dev);
        void __iomem *ioaddr = lp->base;

        if (mii_check_media(&lp->mii, netif_msg_link(lp), init)) {
                /* duplex state has changed */
                if (lp->mii.full_duplex) {
                        lp->tcr_cur_mode |= TCR_SWFDUP;
                } else {
                        lp->tcr_cur_mode &= ~TCR_SWFDUP;
                }

                SMC_SELECT_BANK(lp, 0);
                SMC_SET_TCR(lp, lp->tcr_cur_mode);
        }
}

/*
 * Configures the specified PHY through the MII management interface
 * using Autonegotiation.
 * Calls smc_phy_fixed() if the user has requested a certain config.
 * If RPC ANEG bit is set, the media selection is dependent purely on
 * the selection by the MII (either in the MII BMCR reg or the result
 * of autonegotiation.)  If the RPC ANEG bit is cleared, the selection
 * is controlled by the RPC SPEED and RPC DPLX bits.
 */
static void smc_phy_configure(struct work_struct *work)
{
        struct smc_local *lp =
                container_of(work, struct smc_local, phy_configure);
        struct net_device *dev = lp->dev;
        void __iomem *ioaddr = lp->base;
        int phyaddr = lp->mii.phy_id;
        int my_phy_caps; /* My PHY capabilities */
        int my_ad_caps; /* My Advertised capabilities */
        int status;

        DBG(3, dev, "smc_program_phy()\n");

        spin_lock_irq(&lp->lock);

        /*
         * We should not be called if phy_type is zero.
         */
        if (lp->phy_type == 0)
                goto smc_phy_configure_exit;

        if (smc_phy_reset(dev, phyaddr)) {
                netdev_info(dev, "PHY reset timed out\n");
                goto smc_phy_configure_exit;
        }

        /*
         * Enable PHY Interrupts (for register 18)
         * Interrupts listed here are disabled
         */
        smc_phy_write(dev, phyaddr, PHY_MASK_REG,
                PHY_INT_LOSSSYNC | PHY_INT_CWRD | PHY_INT_SSD |
                PHY_INT_ESD | PHY_INT_RPOL | PHY_INT_JAB |
                PHY_INT_SPDDET | PHY_INT_DPLXDET);

        /* Configure the Receive/Phy Control register */
        SMC_SELECT_BANK(lp, 0);
        SMC_SET_RPC(lp, lp->rpc_cur_mode);

        /* If the user requested no auto neg, then go set his request */
        if (lp->mii.force_media) {
                smc_phy_fixed(dev);
                goto smc_phy_configure_exit;
        }

        /* Copy our capabilities from MII_BMSR to MII_ADVERTISE */
        my_phy_caps = smc_phy_read(dev, phyaddr, MII_BMSR);

        if (!(my_phy_caps & BMSR_ANEGCAPABLE)) {
                netdev_info(dev, "Auto negotiation NOT supported\n");
                smc_phy_fixed(dev);
                goto smc_phy_configure_exit;
        }

        my_ad_caps = ADVERTISE_CSMA; /* I am CSMA capable */

        if (my_phy_caps & BMSR_100BASE4)
                my_ad_caps |= ADVERTISE_100BASE4;
        if (my_phy_caps & BMSR_100FULL)
                my_ad_caps |= ADVERTISE_100FULL;
        if (my_phy_caps & BMSR_100HALF)
                my_ad_caps |= ADVERTISE_100HALF;
        if (my_phy_caps & BMSR_10FULL)
                my_ad_caps |= ADVERTISE_10FULL;
        if (my_phy_caps & BMSR_10HALF)
                my_ad_caps |= ADVERTISE_10HALF;

        /* Disable capabilities not selected by our user */
        if (lp->ctl_rspeed != 100)
                my_ad_caps &= ~(ADVERTISE_100BASE4|ADVERTISE_100FULL|ADVERTISE_100HALF);

        if (!lp->ctl_rfduplx)
                my_ad_caps &= ~(ADVERTISE_100FULL|ADVERTISE_10FULL);

        /* Update our Auto-Neg Advertisement Register */
        smc_phy_write(dev, phyaddr, MII_ADVERTISE, my_ad_caps);
        lp->mii.advertising = my_ad_caps;

        /*
         * Read the register back.  Without this, it appears that when
         * auto-negotiation is restarted, sometimes it isn't ready and
         * the link does not come up.
         */
        status = smc_phy_read(dev, phyaddr, MII_ADVERTISE);

        DBG(2, dev, "phy caps=%x\n", my_phy_caps);
        DBG(2, dev, "phy advertised caps=%x\n", my_ad_caps);

        /* Restart auto-negotiation process in order to advertise my caps */
        smc_phy_write(dev, phyaddr, MII_BMCR, BMCR_ANENABLE | BMCR_ANRESTART);

        smc_phy_check_media(dev, 1);

smc_phy_configure_exit:
        SMC_SELECT_BANK(lp, 2);
        spin_unlock_irq(&lp->lock);
}

/*
 * smc_phy_interrupt
 *
 * Purpose:  Handle interrupts relating to PHY register 18. This is
 *  called from the "hard" interrupt handler under our private spinlock.
 */
static void smc_phy_interrupt(struct net_device *dev)
{
        struct smc_local *lp = netdev_priv(dev);
        int phyaddr = lp->mii.phy_id;
        int phy18;

        DBG(2, dev, "%s\n", __func__);

        if (lp->phy_type == 0)
                return;

        for(;;) {
                smc_phy_check_media(dev, 0);

                /* Read PHY Register 18, Status Output */
                phy18 = smc_phy_read(dev, phyaddr, PHY_INT_REG);
                if ((phy18 & PHY_INT_INT) == 0)
                        break;
        }
}

/*--- END PHY CONTROL AND CONFIGURATION-------------------------------------*/

static void smc_10bt_check_media(struct net_device *dev, int init)
{
        struct smc_local *lp = netdev_priv(dev);
        void __iomem *ioaddr = lp->base;
        unsigned int old_carrier, new_carrier;

        old_carrier = netif_carrier_ok(dev) ? 1 : 0;

        SMC_SELECT_BANK(lp, 0);
        new_carrier = (SMC_GET_EPH_STATUS(lp) & ES_LINK_OK) ? 1 : 0;
        SMC_SELECT_BANK(lp, 2);

        if (init || (old_carrier != new_carrier)) {
                if (!new_carrier) {
                        netif_carrier_off(dev);
                } else {
                        netif_carrier_on(dev);
                }
                if (netif_msg_link(lp))
                        netdev_info(dev, "link %s\n",
                                    new_carrier ? "up" : "down");
        }
}

static void smc_eph_interrupt(struct net_device *dev)
{
        struct smc_local *lp = netdev_priv(dev);
        void __iomem *ioaddr = lp->base;
        unsigned int ctl;

        smc_10bt_check_media(dev, 0);

        SMC_SELECT_BANK(lp, 1);
        ctl = SMC_GET_CTL(lp);
        SMC_SET_CTL(lp, ctl & ~CTL_LE_ENABLE);
        SMC_SET_CTL(lp, ctl);
        SMC_SELECT_BANK(lp, 2);
}

/*
 * This is the main routine of the driver, to handle the device when
 * it needs some attention.
 */
static irqreturn_t smc_interrupt(int irq, void *dev_id)
{
        struct net_device *dev = dev_id;
        struct smc_local *lp = netdev_priv(dev);
        void __iomem *ioaddr = lp->base;
        int status, mask, timeout, card_stats;
        int saved_pointer;

        DBG(3, dev, "%s\n", __func__);

        spin_lock(&lp->lock);

        /* A preamble may be used when there is a potential race
         * between the interruptible transmit functions and this
         * ISR. */
        SMC_INTERRUPT_PREAMBLE;

        saved_pointer = SMC_GET_PTR(lp);
        mask = SMC_GET_INT_MASK(lp);
        SMC_SET_INT_MASK(lp, 0);

        /* set a timeout value, so I don't stay here forever */
        timeout = MAX_IRQ_LOOPS;

        do {
                status = SMC_GET_INT(lp);

                DBG(2, dev, "INT 0x%02x MASK 0x%02x MEM 0x%04x FIFO 0x%04x\n",
                    status, mask,
                    ({ int meminfo; SMC_SELECT_BANK(lp, 0);
                       meminfo = SMC_GET_MIR(lp);
                       SMC_SELECT_BANK(lp, 2); meminfo; }),
                    SMC_GET_FIFO(lp));

                status &= mask;
                if (!status)
                        break;

                if (status & IM_TX_INT) {
                        /* do this before RX as it will free memory quickly */
                        DBG(3, dev, "TX int\n");
                        smc_tx(dev);
                        SMC_ACK_INT(lp, IM_TX_INT);
                        if (THROTTLE_TX_PKTS)
                                netif_wake_queue(dev);
                } else if (status & IM_RCV_INT) {
                        DBG(3, dev, "RX irq\n");
                        smc_rcv(dev);
                } else if (status & IM_ALLOC_INT) {
                        DBG(3, dev, "Allocation irq\n");
                        tasklet_hi_schedule(&lp->tx_task);
                        mask &= ~IM_ALLOC_INT;
                } else if (status & IM_TX_EMPTY_INT) {
                        DBG(3, dev, "TX empty\n");
                        mask &= ~IM_TX_EMPTY_INT;

                        /* update stats */
                        SMC_SELECT_BANK(lp, 0);
                        card_stats = SMC_GET_COUNTER(lp);
                        SMC_SELECT_BANK(lp, 2);

                        /* single collisions */
                        dev->stats.collisions += card_stats & 0xF;
                        card_stats >>= 4;

                        /* multiple collisions */
                        dev->stats.collisions += card_stats & 0xF;
                } else if (status & IM_RX_OVRN_INT) {
                        DBG(1, dev, "RX overrun (EPH_ST 0x%04x)\n",
                            ({ int eph_st; SMC_SELECT_BANK(lp, 0);
                               eph_st = SMC_GET_EPH_STATUS(lp);
                               SMC_SELECT_BANK(lp, 2); eph_st; }));
                        SMC_ACK_INT(lp, IM_RX_OVRN_INT);
                        dev->stats.rx_errors++;
                        dev->stats.rx_fifo_errors++;
                } else if (status & IM_EPH_INT) {
                        smc_eph_interrupt(dev);
                } else if (status & IM_MDINT) {
                        SMC_ACK_INT(lp, IM_MDINT);
                        smc_phy_interrupt(dev);
                } else if (status & IM_ERCV_INT) {
                        SMC_ACK_INT(lp, IM_ERCV_INT);
                        PRINTK(dev, "UNSUPPORTED: ERCV INTERRUPT\n");
                }
        } while (--timeout);

        /* restore register states */
        SMC_SET_PTR(lp, saved_pointer);
        SMC_SET_INT_MASK(lp, mask);
        spin_unlock(&lp->lock);

#ifndef CONFIG_NET_POLL_CONTROLLER
        if (timeout == MAX_IRQ_LOOPS)
                PRINTK(dev, "spurious interrupt (mask = 0x%02x)\n",
                       mask);
#endif
        DBG(3, dev, "Interrupt done (%d loops)\n",
            MAX_IRQ_LOOPS - timeout);

        /*
         * We return IRQ_HANDLED unconditionally here even if there was
         * nothing to do.  There is a possibility that a packet might
         * get enqueued into the chip right after TX_EMPTY_INT is raised
         * but just before the CPU acknowledges the IRQ.
         * Better take an unneeded IRQ in some occasions than complexifying
         * the code for all cases.
         */
        return IRQ_HANDLED;
}

#ifdef CONFIG_NET_POLL_CONTROLLER
/*
 * Polling receive - used by netconsole and other diagnostic tools
 * to allow network i/o with interrupts disabled.
 */
static void smc_poll_controller(struct net_device *dev)
{
        disable_irq(dev->irq);
        smc_interrupt(dev->irq, dev);
        enable_irq(dev->irq);
}
#endif

/* Our watchdog timed out. Called by the networking layer */
static void smc_timeout(struct net_device *dev)
{
        struct smc_local *lp = netdev_priv(dev);
        void __iomem *ioaddr = lp->base;
        int status, mask, eph_st, meminfo, fifo;

        DBG(2, dev, "%s\n", __func__);

        spin_lock_irq(&lp->lock);
        status = SMC_GET_INT(lp);
        mask = SMC_GET_INT_MASK(lp);
        fifo = SMC_GET_FIFO(lp);
        SMC_SELECT_BANK(lp, 0);
        eph_st = SMC_GET_EPH_STATUS(lp);
        meminfo = SMC_GET_MIR(lp);
        SMC_SELECT_BANK(lp, 2);
        spin_unlock_irq(&lp->lock);
        PRINTK(dev, "TX timeout (INT 0x%02x INTMASK 0x%02x MEM 0x%04x FIFO 0x%04x EPH_ST 0x%04x)\n",
               status, mask, meminfo, fifo, eph_st);

        smc_reset(dev);
        smc_enable(dev);

        /*
         * Reconfiguring the PHY doesn't seem like a bad idea here, but
         * smc_phy_configure() calls msleep() which calls schedule_timeout()
         * which calls schedule().  Hence we use a work queue.
         */
        if (lp->phy_type != 0)
                schedule_work(&lp->phy_configure);

        /* We can accept TX packets again */
        netif_trans_update(dev); /* prevent tx timeout */
        netif_wake_queue(dev);
}

/*
 * This routine will, depending on the values passed to it,
 * either make it accept multicast packets, go into
 * promiscuous mode (for TCPDUMP and cousins) or accept
 * a select set of multicast packets
 */
static void smc_set_multicast_list(struct net_device *dev)
{
        struct smc_local *lp = netdev_priv(dev);
        void __iomem *ioaddr = lp->base;
        unsigned char multicast_table[8];
        int update_multicast = 0;

        DBG(2, dev, "%s\n", __func__);

        if (dev->flags & IFF_PROMISC) {
                DBG(2, dev, "RCR_PRMS\n");
                lp->rcr_cur_mode |= RCR_PRMS;
        }

/* BUG?  I never disable promiscuous mode if multicasting was turned on.
   Now, I turn off promiscuous mode, but I don't do anything to multicasting
   when promiscuous mode is turned on.
*/

        /*
         * Here, I am setting this to accept all multicast packets.
         * I don't need to zero the multicast table, because the flag is
         * checked before the table is
         */
        else if (dev->flags & IFF_ALLMULTI || netdev_mc_count(dev) > 16) {
                DBG(2, dev, "RCR_ALMUL\n");
                lp->rcr_cur_mode |= RCR_ALMUL;
        }

        /*
         * This sets the internal hardware table to filter out unwanted
         * multicast packets before they take up memory.
         *
         * The SMC chip uses a hash table where the high 6 bits of the CRC of
         * address are the offset into the table.  If that bit is 1, then the
         * multicast packet is accepted.  Otherwise, it's dropped silently.
         *
         * To use the 6 bits as an offset into the table, the high 3 bits are
         * the number of the 8 bit register, while the low 3 bits are the bit
         * within that register.
         */
        else if (!netdev_mc_empty(dev)) {
                struct netdev_hw_addr *ha;

                /* table for flipping the order of 3 bits */
                static const unsigned char invert3[] = {0, 4, 2, 6, 1, 5, 3, 7};

                /* start with a table of all zeros: reject all */
                memset(multicast_table, 0, sizeof(multicast_table));

                netdev_for_each_mc_addr(ha, dev) {
                        int position;

                        /* only use the low order bits */
                        position = crc32_le(~0, ha->addr, 6) & 0x3f;

                        /* do some messy swapping to put the bit in the right spot */
                        multicast_table[invert3[position&7]] |=
                                (1<<invert3[(position>>3)&7]);
                }

                /* be sure I get rid of flags I might have set */
                lp->rcr_cur_mode &= ~(RCR_PRMS | RCR_ALMUL);

                /* now, the table can be loaded into the chipset */
                update_multicast = 1;
        } else  {
                DBG(2, dev, "~(RCR_PRMS|RCR_ALMUL)\n");
                lp->rcr_cur_mode &= ~(RCR_PRMS | RCR_ALMUL);

                /*
                 * since I'm disabling all multicast entirely, I need to
                 * clear the multicast list
                 */
                memset(multicast_table, 0, sizeof(multicast_table));
                update_multicast = 1;
        }

        spin_lock_irq(&lp->lock);
        SMC_SELECT_BANK(lp, 0);
        SMC_SET_RCR(lp, lp->rcr_cur_mode);
        if (update_multicast) {
                SMC_SELECT_BANK(lp, 3);
                SMC_SET_MCAST(lp, multicast_table);
        }
        SMC_SELECT_BANK(lp, 2);
        spin_unlock_irq(&lp->lock);
}


/*
 * Open and Initialize the board
 *
 * Set up everything, reset the card, etc..
 */
static int
smc_open(struct net_device *dev)
{
        struct smc_local *lp = netdev_priv(dev);

        DBG(2, dev, "%s\n", __func__);

        /* Setup the default Register Modes */
        lp->tcr_cur_mode = TCR_DEFAULT;
        lp->rcr_cur_mode = RCR_DEFAULT;
        lp->rpc_cur_mode = RPC_DEFAULT |
                                lp->cfg.leda << RPC_LSXA_SHFT |
                                lp->cfg.ledb << RPC_LSXB_SHFT;

        /*
         * If we are not using a MII interface, we need to
         * monitor our own carrier signal to detect faults.
         */
        if (lp->phy_type == 0)
                lp->tcr_cur_mode |= TCR_MON_CSN;

        /* reset the hardware */
        smc_reset(dev);
        smc_enable(dev);

        /* Configure the PHY, initialize the link state */
        if (lp->phy_type != 0)
                smc_phy_configure(&lp->phy_configure);
        else {
                spin_lock_irq(&lp->lock);
                smc_10bt_check_media(dev, 1);
                spin_unlock_irq(&lp->lock);
        }

        netif_start_queue(dev);
        return 0;
}

/*
 * smc_close
 *
 * this makes the board clean up everything that it can
 * and not talk to the outside world.   Caused by
 * an 'ifconfig ethX down'
 */
static int smc_close(struct net_device *dev)
{
        struct smc_local *lp = netdev_priv(dev);

        DBG(2, dev, "%s\n", __func__);

        netif_stop_queue(dev);
        netif_carrier_off(dev);

        /* clear everything */
        smc_shutdown(dev);
        tasklet_kill(&lp->tx_task);
        smc_phy_powerdown(dev);
        return 0;
}

/*
 * Ethtool support
 */
static int
smc_ethtool_get_link_ksettings(struct net_device *dev,
                               struct ethtool_link_ksettings *cmd)
{
        struct smc_local *lp = netdev_priv(dev);
        int ret;

        if (lp->phy_type != 0) {
                spin_lock_irq(&lp->lock);
                ret = mii_ethtool_get_link_ksettings(&lp->mii, cmd);
                spin_unlock_irq(&lp->lock);
        } else {
                u32 supported = SUPPORTED_10baseT_Half |
                                 SUPPORTED_10baseT_Full |
                                 SUPPORTED_TP | SUPPORTED_AUI;

                if (lp->ctl_rspeed == 10)
                        cmd->base.speed = SPEED_10;
                else if (lp->ctl_rspeed == 100)
                        cmd->base.speed = SPEED_100;

                cmd->base.autoneg = AUTONEG_DISABLE;
                cmd->base.port = 0;
                cmd->base.duplex = lp->tcr_cur_mode & TCR_SWFDUP ?
                        DUPLEX_FULL : DUPLEX_HALF;

                ethtool_convert_legacy_u32_to_link_mode(
                        cmd->link_modes.supported, supported);

                ret = 0;
        }

        return ret;
}

static int
smc_ethtool_set_link_ksettings(struct net_device *dev,
                               const struct ethtool_link_ksettings *cmd)
{
        struct smc_local *lp = netdev_priv(dev);
        int ret;

        if (lp->phy_type != 0) {
                spin_lock_irq(&lp->lock);
                ret = mii_ethtool_set_link_ksettings(&lp->mii, cmd);
                spin_unlock_irq(&lp->lock);
        } else {
                if (cmd->base.autoneg != AUTONEG_DISABLE ||
                    cmd->base.speed != SPEED_10 ||
                    (cmd->base.duplex != DUPLEX_HALF &&
                     cmd->base.duplex != DUPLEX_FULL) ||
                    (cmd->base.port != PORT_TP && cmd->base.port != PORT_AUI))
                        return -EINVAL;

//              lp->port = cmd->base.port;
                lp->ctl_rfduplx = cmd->base.duplex == DUPLEX_FULL;

//              if (netif_running(dev))
//                      smc_set_port(dev);

                ret = 0;
        }

        return ret;
}

static void
smc_ethtool_getdrvinfo(struct net_device *dev, struct ethtool_drvinfo *info)
{
        strlcpy(info->driver, CARDNAME, sizeof(info->driver));
        strlcpy(info->version, version, sizeof(info->version));
        strlcpy(info->bus_info, dev_name(dev->dev.parent),
                sizeof(info->bus_info));
}

static int smc_ethtool_nwayreset(struct net_device *dev)
{
        struct smc_local *lp = netdev_priv(dev);
        int ret = -EINVAL;

        if (lp->phy_type != 0) {
                spin_lock_irq(&lp->lock);
                ret = mii_nway_restart(&lp->mii);
                spin_unlock_irq(&lp->lock);
        }

        return ret;
}

static u32 smc_ethtool_getmsglevel(struct net_device *dev)
{
        struct smc_local *lp = netdev_priv(dev);
        return lp->msg_enable;
}

static void smc_ethtool_setmsglevel(struct net_device *dev, u32 level)
{
        struct smc_local *lp = netdev_priv(dev);
        lp->msg_enable = level;
}

static int smc_write_eeprom_word(struct net_device *dev, u16 addr, u16 word)
{
        u16 ctl;
        struct smc_local *lp = netdev_priv(dev);
        void __iomem *ioaddr = lp->base;

        spin_lock_irq(&lp->lock);
        /* load word into GP register */
        SMC_SELECT_BANK(lp, 1);
        SMC_SET_GP(lp, word);
        /* set the address to put the data in EEPROM */
        SMC_SELECT_BANK(lp, 2);
        SMC_SET_PTR(lp, addr);
        /* tell it to write */
        SMC_SELECT_BANK(lp, 1);
        ctl = SMC_GET_CTL(lp);
        SMC_SET_CTL(lp, ctl | (CTL_EEPROM_SELECT | CTL_STORE));
        /* wait for it to finish */
        do {
                udelay(1);
        } while (SMC_GET_CTL(lp) & CTL_STORE);
        /* clean up */
        SMC_SET_CTL(lp, ctl);
        SMC_SELECT_BANK(lp, 2);
        spin_unlock_irq(&lp->lock);
        return 0;
}

static int smc_read_eeprom_word(struct net_device *dev, u16 addr, u16 *word)
{
        u16 ctl;
        struct smc_local *lp = netdev_priv(dev);
        void __iomem *ioaddr = lp->base;

        spin_lock_irq(&lp->lock);
        /* set the EEPROM address to get the data from */
        SMC_SELECT_BANK(lp, 2);
        SMC_SET_PTR(lp, addr | PTR_READ);
        /* tell it to load */
        SMC_SELECT_BANK(lp, 1);
        SMC_SET_GP(lp, 0xffff); /* init to known */
        ctl = SMC_GET_CTL(lp);
        SMC_SET_CTL(lp, ctl | (CTL_EEPROM_SELECT | CTL_RELOAD));
        /* wait for it to finish */
        do {
                udelay(1);
        } while (SMC_GET_CTL(lp) & CTL_RELOAD);
        /* read word from GP register */
        *word = SMC_GET_GP(lp);
        /* clean up */
        SMC_SET_CTL(lp, ctl);
        SMC_SELECT_BANK(lp, 2);
        spin_unlock_irq(&lp->lock);
        return 0;
}

static int smc_ethtool_geteeprom_len(struct net_device *dev)
{
        return 0x23 * 2;
}

static int smc_ethtool_geteeprom(struct net_device *dev,
                struct ethtool_eeprom *eeprom, u8 *data)
{
        int i;
        int imax;

        DBG(1, dev, "Reading %d bytes at %d(0x%x)\n",
                eeprom->len, eeprom->offset, eeprom->offset);
        imax = smc_ethtool_geteeprom_len(dev);
        for (i = 0; i < eeprom->len; i += 2) {
                int ret;
                u16 wbuf;
                int offset = i + eeprom->offset;
                if (offset > imax)
                        break;
                ret = smc_read_eeprom_word(dev, offset >> 1, &wbuf);
                if (ret != 0)
                        return ret;
                DBG(2, dev, "Read 0x%x from 0x%x\n", wbuf, offset >> 1);
                data[i] = (wbuf >> 8) & 0xff;
                data[i+1] = wbuf & 0xff;
        }
        return 0;
}

static int smc_ethtool_seteeprom(struct net_device *dev,
                struct ethtool_eeprom *eeprom, u8 *data)
{
        int i;
        int imax;

        DBG(1, dev, "Writing %d bytes to %d(0x%x)\n",
            eeprom->len, eeprom->offset, eeprom->offset);
        imax = smc_ethtool_geteeprom_len(dev);
        for (i = 0; i < eeprom->len; i += 2) {
                int ret;
                u16 wbuf;
                int offset = i + eeprom->offset;
                if (offset > imax)
                        break;
                wbuf = (data[i] << 8) | data[i + 1];
                DBG(2, dev, "Writing 0x%x to 0x%x\n", wbuf, offset >> 1);
                ret = smc_write_eeprom_word(dev, offset >> 1, wbuf);
                if (ret != 0)
                        return ret;
        }
        return 0;
}


static const struct ethtool_ops smc_ethtool_ops = {
        .get_drvinfo    = smc_ethtool_getdrvinfo,

        .get_msglevel   = smc_ethtool_getmsglevel,
        .set_msglevel   = smc_ethtool_setmsglevel,
        .nway_reset     = smc_ethtool_nwayreset,
        .get_link       = ethtool_op_get_link,
        .get_eeprom_len = smc_ethtool_geteeprom_len,
        .get_eeprom     = smc_ethtool_geteeprom,
        .set_eeprom     = smc_ethtool_seteeprom,
        .get_link_ksettings     = smc_ethtool_get_link_ksettings,
        .set_link_ksettings     = smc_ethtool_set_link_ksettings,
};

static const struct net_device_ops smc_netdev_ops = {
        .ndo_open               = smc_open,
        .ndo_stop               = smc_close,
        .ndo_start_xmit         = smc_hard_start_xmit,
        .ndo_tx_timeout         = smc_timeout,
        .ndo_set_rx_mode        = smc_set_multicast_list,
        .ndo_validate_addr      = eth_validate_addr,
        .ndo_set_mac_address    = eth_mac_addr,
#ifdef CONFIG_NET_POLL_CONTROLLER
        .ndo_poll_controller    = smc_poll_controller,
#endif
};

/*
 * smc_findirq
 *
 * This routine has a simple purpose -- make the SMC chip generate an
 * interrupt, so an auto-detect routine can detect it, and find the IRQ,
 */
/*
 * does this still work?
 *
 * I just deleted auto_irq.c, since it was never built...
 *   --jgarzik
 */
static int smc_findirq(struct smc_local *lp)
{
        void __iomem *ioaddr = lp->base;
        int timeout = 20;
        unsigned long cookie;

        DBG(2, lp->dev, "%s: %s\n", CARDNAME, __func__);

        cookie = probe_irq_on();

        /*
         * What I try to do here is trigger an ALLOC_INT. This is done
         * by allocating a small chunk of memory, which will give an interrupt
         * when done.
         */
        /* enable ALLOCation interrupts ONLY */
        SMC_SELECT_BANK(lp, 2);
        SMC_SET_INT_MASK(lp, IM_ALLOC_INT);

        /*
         * Allocate 512 bytes of memory.  Note that the chip was just
         * reset so all the memory is available
         */
        SMC_SET_MMU_CMD(lp, MC_ALLOC | 1);

        /*
         * Wait until positive that the interrupt has been generated
         */
        do {
                int int_status;
                udelay(10);
                int_status = SMC_GET_INT(lp);
                if (int_status & IM_ALLOC_INT)
                        break;          /* got the interrupt */
        } while (--timeout);

        /*
         * there is really nothing that I can do here if timeout fails,
         * as autoirq_report will return a 0 anyway, which is what I
         * want in this case.   Plus, the clean up is needed in both
         * cases.
         */

        /* and disable all interrupts again */
        SMC_SET_INT_MASK(lp, 0);

        /* and return what I found */
        return probe_irq_off(cookie);
}

/*
 * Function: smc_probe(unsigned long ioaddr)
 *
 * Purpose:
 *      Tests to see if a given ioaddr points to an SMC91x chip.
 *      Returns a 0 on success
 *
 * Algorithm:
 *      (1) see if the high byte of BANK_SELECT is 0x33
 *      (2) compare the ioaddr with the base register's address
 *      (3) see if I recognize the chip ID in the appropriate register
 *
 * Here I do typical initialization tasks.
 *
 * o  Initialize the structure if needed
 * o  print out my vanity message if not done so already
 * o  print out what type of hardware is detected
 * o  print out the ethernet address
 * o  find the IRQ
 * o  set up my private data
 * o  configure the dev structure with my subroutines
 * o  actually GRAB the irq.
 * o  GRAB the region
 */
static int smc_probe(struct net_device *dev, void __iomem *ioaddr,
                     unsigned long irq_flags)
{
        struct smc_local *lp = netdev_priv(dev);
        int retval;
        unsigned int val, revision_register;
        const char *version_string;

        DBG(2, dev, "%s: %s\n", CARDNAME, __func__);

        /* First, see if the high byte is 0x33 */
        val = SMC_CURRENT_BANK(lp);
        DBG(2, dev, "%s: bank signature probe returned 0x%04x\n",
            CARDNAME, val);
        if ((val & 0xFF00) != 0x3300) {
                if ((val & 0xFF) == 0x33) {
                        netdev_warn(dev,
                                    "%s: Detected possible byte-swapped interface at IOADDR %p\n",
                                    CARDNAME, ioaddr);
                }
                retval = -ENODEV;
                goto err_out;
        }

        /*
         * The above MIGHT indicate a device, but I need to write to
         * further test this.
         */
        SMC_SELECT_BANK(lp, 0);
        val = SMC_CURRENT_BANK(lp);
        if ((val & 0xFF00) != 0x3300) {
                retval = -ENODEV;
                goto err_out;
        }

        /*
         * well, we've already written once, so hopefully another
         * time won't hurt.  This time, I need to switch the bank
         * register to bank 1, so I can access the base address
         * register
         */
        SMC_SELECT_BANK(lp, 1);
        val = SMC_GET_BASE(lp);
        val = ((val & 0x1F00) >> 3) << SMC_IO_SHIFT;
        if (((unsigned long)ioaddr & (0x3e0 << SMC_IO_SHIFT)) != val) {
                netdev_warn(dev, "%s: IOADDR %p doesn't match configuration (%x).\n",
                            CARDNAME, ioaddr, val);
        }

        /*
         * check if the revision register is something that I
         * recognize.  These might need to be added to later,
         * as future revisions could be added.
         */
        SMC_SELECT_BANK(lp, 3);
        revision_register = SMC_GET_REV(lp);
        DBG(2, dev, "%s: revision = 0x%04x\n", CARDNAME, revision_register);
        version_string = chip_ids[ (revision_register >> 4) & 0xF];
        if (!version_string || (revision_register & 0xff00) != 0x3300) {
                /* I don't recognize this chip, so... */
                netdev_warn(dev, "%s: IO %p: Unrecognized revision register 0x%04x, Contact author.\n",
                            CARDNAME, ioaddr, revision_register);

                retval = -ENODEV;
                goto err_out;
        }

        /* At this point I'll assume that the chip is an SMC91x. */
        pr_info_once("%s\n", version);

        /* fill in some of the fields */
        dev->base_addr = (unsigned long)ioaddr;
        lp->base = ioaddr;
        lp->version = revision_register & 0xff;
        spin_lock_init(&lp->lock);

        /* Get the MAC address */
        SMC_SELECT_BANK(lp, 1);
        SMC_GET_MAC_ADDR(lp, dev->dev_addr);

        /* now, reset the chip, and put it into a known state */
        smc_reset(dev);

        /*
         * If dev->irq is 0, then the device has to be banged on to see
         * what the IRQ is.
         *
         * This banging doesn't always detect the IRQ, for unknown reasons.
         * a workaround is to reset the chip and try again.
         *
         * Interestingly, the DOS packet driver *SETS* the IRQ on the card to
         * be what is requested on the command line.   I don't do that, mostly
         * because the card that I have uses a non-standard method of accessing
         * the IRQs, and because this _should_ work in most configurations.
         *
         * Specifying an IRQ is done with the assumption that the user knows
         * what (s)he is doing.  No checking is done!!!!
         */
        if (dev->irq < 1) {
                int trials;

                trials = 3;
                while (trials--) {
                        dev->irq = smc_findirq(lp);
                        if (dev->irq)
                                break;
                        /* kick the card and try again */
                        smc_reset(dev);
                }
        }
        if (dev->irq == 0) {
                netdev_warn(dev, "Couldn't autodetect your IRQ. Use irq=xx.\n");
                retval = -ENODEV;
                goto err_out;
        }
        dev->irq = irq_canonicalize(dev->irq);

        dev->watchdog_timeo = msecs_to_jiffies(watchdog);
        dev->netdev_ops = &smc_netdev_ops;
        dev->ethtool_ops = &smc_ethtool_ops;

        tasklet_init(&lp->tx_task, smc_hardware_send_pkt, (unsigned long)dev);
        INIT_WORK(&lp->phy_configure, smc_phy_configure);
        lp->dev = dev;
        lp->mii.phy_id_mask = 0x1f;
        lp->mii.reg_num_mask = 0x1f;
        lp->mii.force_media = 0;
        lp->mii.full_duplex = 0;
        lp->mii.dev = dev;
        lp->mii.mdio_read = smc_phy_read;
        lp->mii.mdio_write = smc_phy_write;

        /*
         * Locate the phy, if any.
         */
        if (lp->version >= (CHIP_91100 << 4))
                smc_phy_detect(dev);

        /* then shut everything down to save power */

        smc_shutdown(dev);
        smc_phy_powerdown(dev);

        /* Set default parameters */
        lp->msg_enable = NETIF_MSG_LINK;
        lp->ctl_rfduplx = 0;
        lp->ctl_rspeed = 10;

        if (lp->version >= (CHIP_91100 << 4)) {
                lp->ctl_rfduplx = 1;
                lp->ctl_rspeed = 100;
        }

        /* Grab the IRQ */
        retval = request_irq(dev->irq, smc_interrupt, irq_flags, dev->name, dev);
        if (retval)
                goto err_out;

#ifdef CONFIG_ARCH_PXA
#  ifdef SMC_USE_PXA_DMA
        lp->cfg.flags |= SMC91X_USE_DMA;
#  endif
        if (lp->cfg.flags & SMC91X_USE_DMA) {
                dma_cap_mask_t mask;
                struct pxad_param param;

                dma_cap_zero(mask);
                dma_cap_set(DMA_SLAVE, mask);
                param.prio = PXAD_PRIO_LOWEST;
                param.drcmr = -1UL;

                lp->dma_chan =
                        dma_request_slave_channel_compat(mask, pxad_filter_fn,
                                                         &param, &dev->dev,
                                                         "data");
        }
#endif

        retval = register_netdev(dev);
        if (retval == 0) {
                /* now, print out the card info, in a short format.. */
                netdev_info(dev, "%s (rev %d) at %p IRQ %d",
                            version_string, revision_register & 0x0f,
                            lp->base, dev->irq);

                if (lp->dma_chan)
                        pr_cont(" DMA %p", lp->dma_chan);

                pr_cont("%s%s\n",
                        lp->cfg.flags & SMC91X_NOWAIT ? " [nowait]" : "",
                        THROTTLE_TX_PKTS ? " [throttle_tx]" : "");

                if (!is_valid_ether_addr(dev->dev_addr)) {
                        netdev_warn(dev, "Invalid ethernet MAC address. Please set using ifconfig\n");
                } else {
                        /* Print the Ethernet address */
                        netdev_info(dev, "Ethernet addr: %pM\n",
                                    dev->dev_addr);
                }

                if (lp->phy_type == 0) {
                        PRINTK(dev, "No PHY found\n");
                } else if ((lp->phy_type & 0xfffffff0) == 0x0016f840) {
                        PRINTK(dev, "PHY LAN83C183 (LAN91C111 Internal)\n");
                } else if ((lp->phy_type & 0xfffffff0) == 0x02821c50) {
                        PRINTK(dev, "PHY LAN83C180\n");
                }
        }

err_out:
#ifdef CONFIG_ARCH_PXA
        if (retval && lp->dma_chan)
                dma_release_channel(lp->dma_chan);
#endif
        return retval;
}

static int smc_enable_device(struct platform_device *pdev)
{
        struct net_device *ndev = platform_get_drvdata(pdev);
        struct smc_local *lp = netdev_priv(ndev);
        unsigned long flags;
        unsigned char ecor, ecsr;
        void __iomem *addr;
        struct resource * res;

        res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "smc91x-attrib");
        if (!res)
                return 0;

        /*
         * Map the attribute space.  This is overkill, but clean.
         */
        addr = ioremap(res->start, ATTRIB_SIZE);
        if (!addr)
                return -ENOMEM;

        /*
         * Reset the device.  We must disable IRQs around this
         * since a reset causes the IRQ line become active.
         */
        local_irq_save(flags);
        ecor = readb(addr + (ECOR << SMC_IO_SHIFT)) & ~ECOR_RESET;
        writeb(ecor | ECOR_RESET, addr + (ECOR << SMC_IO_SHIFT));
        readb(addr + (ECOR << SMC_IO_SHIFT));

        /*
         * Wait 100us for the chip to reset.
         */
        udelay(100);

        /*
         * The device will ignore all writes to the enable bit while
         * reset is asserted, even if the reset bit is cleared in the
         * same write.  Must clear reset first, then enable the device.
         */
        writeb(ecor, addr + (ECOR << SMC_IO_SHIFT));
        writeb(ecor | ECOR_ENABLE, addr + (ECOR << SMC_IO_SHIFT));

        /*
         * Set the appropriate byte/word mode.
         */
        ecsr = readb(addr + (ECSR << SMC_IO_SHIFT)) & ~ECSR_IOIS8;
        if (!SMC_16BIT(lp))
                ecsr |= ECSR_IOIS8;
        writeb(ecsr, addr + (ECSR << SMC_IO_SHIFT));
        local_irq_restore(flags);

        iounmap(addr);

        /*
         * Wait for the chip to wake up.  We could poll the control
         * register in the main register space, but that isn't mapped
         * yet.  We know this is going to take 750us.
         */
        msleep(1);

        return 0;
}

static int smc_request_attrib(struct platform_device *pdev,
                              struct net_device *ndev)
{
        struct resource * res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "smc91x-attrib");
        struct smc_local *lp __maybe_unused = netdev_priv(ndev);

        if (!res)
                return 0;

        if (!request_mem_region(res->start, ATTRIB_SIZE, CARDNAME))
                return -EBUSY;

        return 0;
}

static void smc_release_attrib(struct platform_device *pdev,
                               struct net_device *ndev)
{
        struct resource * res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "smc91x-attrib");
        struct smc_local *lp __maybe_unused = netdev_priv(ndev);

        if (res)
                release_mem_region(res->start, ATTRIB_SIZE);
}

static inline void smc_request_datacs(struct platform_device *pdev, struct net_device *ndev)
{
        if (SMC_CAN_USE_DATACS) {
                struct resource * res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "smc91x-data32");
                struct smc_local *lp = netdev_priv(ndev);

                if (!res)
                        return;

                if(!request_mem_region(res->start, SMC_DATA_EXTENT, CARDNAME)) {
                        netdev_info(ndev, "%s: failed to request datacs memory region.\n",
                                    CARDNAME);
                        return;
                }

                lp->datacs = ioremap(res->start, SMC_DATA_EXTENT);
        }
}

static void smc_release_datacs(struct platform_device *pdev, struct net_device *ndev)
{
        if (SMC_CAN_USE_DATACS) {
                struct smc_local *lp = netdev_priv(ndev);
                struct resource * res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "smc91x-data32");

                if (lp->datacs)
                        iounmap(lp->datacs);

                lp->datacs = NULL;

                if (res)
                        release_mem_region(res->start, SMC_DATA_EXTENT);
        }
}

static const struct acpi_device_id smc91x_acpi_match[] = {
        { "LNRO0003", 0 },
        { }
};
MODULE_DEVICE_TABLE(acpi, smc91x_acpi_match);

#if IS_BUILTIN(CONFIG_OF)
static const struct of_device_id smc91x_match[] = {
        { .compatible = "smsc,lan91c94", },
        { .compatible = "smsc,lan91c111", },
        {},
};
MODULE_DEVICE_TABLE(of, smc91x_match);

/**
 * of_try_set_control_gpio - configure a gpio if it exists
 */
static int try_toggle_control_gpio(struct device *dev,
                                   struct gpio_desc **desc,
                                   const char *name, int index,
                                   int value, unsigned int nsdelay)
{
        struct gpio_desc *gpio = *desc;
        enum gpiod_flags flags = value ? GPIOD_OUT_LOW : GPIOD_OUT_HIGH;

        gpio = devm_gpiod_get_index_optional(dev, name, index, flags);
        if (IS_ERR(gpio))
                return PTR_ERR(gpio);

        if (gpio) {
                if (nsdelay)
                        usleep_range(nsdelay, 2 * nsdelay);
                gpiod_set_value_cansleep(gpio, value);
        }
        *desc = gpio;

        return 0;
}
#endif

/*
 * smc_init(void)
 *   Input parameters:
 *      dev->base_addr == 0, try to find all possible locations
 *      dev->base_addr > 0x1ff, this is the address to check
 *      dev->base_addr == <anything else>, return failure code
 *
 *   Output:
 *      0 --> there is a device
 *      anything else, error
 */
static int smc_drv_probe(struct platform_device *pdev)
{
        struct smc91x_platdata *pd = dev_get_platdata(&pdev->dev);
        const struct of_device_id *match = NULL;
        struct smc_local *lp;
        struct net_device *ndev;
        struct resource *res;
        unsigned int __iomem *addr;
        unsigned long irq_flags = SMC_IRQ_FLAGS;
        unsigned long irq_resflags;
        int ret;

        ndev = alloc_etherdev(sizeof(struct smc_local));
        if (!ndev) {
                ret = -ENOMEM;
                goto out;
        }
        SET_NETDEV_DEV(ndev, &pdev->dev);

        /* get configuration from platform data, only allow use of
         * bus width if both SMC_CAN_USE_xxx and SMC91X_USE_xxx are set.
         */

        lp = netdev_priv(ndev);
        lp->cfg.flags = 0;

        if (pd) {
                memcpy(&lp->cfg, pd, sizeof(lp->cfg));
                lp->io_shift = SMC91X_IO_SHIFT(lp->cfg.flags);

                if (!SMC_8BIT(lp) && !SMC_16BIT(lp)) {
                        dev_err(&pdev->dev,
                                "at least one of 8-bit or 16-bit access support is required.\n");
                        ret = -ENXIO;
                        goto out_free_netdev;
                }
        }

#if IS_BUILTIN(CONFIG_OF)
        match = of_match_device(of_match_ptr(smc91x_match), &pdev->dev);
        if (match) {
                u32 val;

                /* Optional pwrdwn GPIO configured? */
                ret = try_toggle_control_gpio(&pdev->dev, &lp->power_gpio,
                                              "power", 0, 0, 100);
                if (ret)
                        return ret;

                /*
                 * Optional reset GPIO configured? Minimum 100 ns reset needed
                 * according to LAN91C96 datasheet page 14.
                 */
                ret = try_toggle_control_gpio(&pdev->dev, &lp->reset_gpio,
                                              "reset", 0, 0, 100);
                if (ret)
                        return ret;

                /*
                 * Need to wait for optional EEPROM to load, max 750 us according
                 * to LAN91C96 datasheet page 55.
                 */
                if (lp->reset_gpio)
                        usleep_range(750, 1000);

                /* Combination of IO widths supported, default to 16-bit */
                if (!device_property_read_u32(&pdev->dev, "reg-io-width",
                                              &val)) {
                        if (val & 1)
                                lp->cfg.flags |= SMC91X_USE_8BIT;
                        if ((val == 0) || (val & 2))
                                lp->cfg.flags |= SMC91X_USE_16BIT;
                        if (val & 4)
                                lp->cfg.flags |= SMC91X_USE_32BIT;
                } else {
                        lp->cfg.flags |= SMC91X_USE_16BIT;
                }
                if (!device_property_read_u32(&pdev->dev, "reg-shift",
                                              &val))
                        lp->io_shift = val;
                lp->cfg.pxa_u16_align4 =
                        device_property_read_bool(&pdev->dev, "pxa-u16-align4");
        }
#endif

        if (!pd && !match) {
                lp->cfg.flags |= (SMC_CAN_USE_8BIT)  ? SMC91X_USE_8BIT  : 0;
                lp->cfg.flags |= (SMC_CAN_USE_16BIT) ? SMC91X_USE_16BIT : 0;
                lp->cfg.flags |= (SMC_CAN_USE_32BIT) ? SMC91X_USE_32BIT : 0;
                lp->cfg.flags |= (nowait) ? SMC91X_NOWAIT : 0;
        }

        if (!lp->cfg.leda && !lp->cfg.ledb) {
                lp->cfg.leda = RPC_LSA_DEFAULT;
                lp->cfg.ledb = RPC_LSB_DEFAULT;
        }

        ndev->dma = (unsigned char)-1;

        res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "smc91x-regs");
        if (!res)
                res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
        if (!res) {
                ret = -ENODEV;
                goto out_free_netdev;
        }


        if (!request_mem_region(res->start, SMC_IO_EXTENT, CARDNAME)) {
                ret = -EBUSY;
                goto out_free_netdev;
        }

        ndev->irq = platform_get_irq(pdev, 0);
        if (ndev->irq < 0) {
                ret = ndev->irq;
                goto out_release_io;
        }
        /*
         * If this platform does not specify any special irqflags, or if
         * the resource supplies a trigger, override the irqflags with
         * the trigger flags from the resource.
         */
        irq_resflags = irqd_get_trigger_type(irq_get_irq_data(ndev->irq));
        if (irq_flags == -1 || irq_resflags & IRQF_TRIGGER_MASK)
                irq_flags = irq_resflags & IRQF_TRIGGER_MASK;

        ret = smc_request_attrib(pdev, ndev);
        if (ret)
                goto out_release_io;
#if defined(CONFIG_ASSABET_NEPONSET)
        if (machine_is_assabet() && machine_has_neponset())
                neponset_ncr_set(NCR_ENET_OSC_EN);
#endif
        platform_set_drvdata(pdev, ndev);
        ret = smc_enable_device(pdev);
        if (ret)
                goto out_release_attrib;

        addr = ioremap(res->start, SMC_IO_EXTENT);
        if (!addr) {
                ret = -ENOMEM;
                goto out_release_attrib;
        }

#ifdef CONFIG_ARCH_PXA
        {
                struct smc_local *lp = netdev_priv(ndev);
                lp->device = &pdev->dev;
                lp->physaddr = res->start;

        }
#endif

        ret = smc_probe(ndev, addr, irq_flags);
        if (ret != 0)
                goto out_iounmap;

        smc_request_datacs(pdev, ndev);

        return 0;

 out_iounmap:
        iounmap(addr);
 out_release_attrib:
        smc_release_attrib(pdev, ndev);
 out_release_io:
        release_mem_region(res->start, SMC_IO_EXTENT);
 out_free_netdev:
        free_netdev(ndev);
 out:
        pr_info("%s: not found (%d).\n", CARDNAME, ret);

        return ret;
}

static int smc_drv_remove(struct platform_device *pdev)
{
        struct net_device *ndev = platform_get_drvdata(pdev);
        struct smc_local *lp = netdev_priv(ndev);
        struct resource *res;

        unregister_netdev(ndev);

        free_irq(ndev->irq, ndev);

#ifdef CONFIG_ARCH_PXA
        if (lp->dma_chan)
                dma_release_channel(lp->dma_chan);
#endif
        iounmap(lp->base);

        smc_release_datacs(pdev,ndev);
        smc_release_attrib(pdev,ndev);

        res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "smc91x-regs");
        if (!res)
                res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
        release_mem_region(res->start, SMC_IO_EXTENT);

        free_netdev(ndev);

        return 0;
}

static int smc_drv_suspend(struct device *dev)
{
        struct platform_device *pdev = to_platform_device(dev);
        struct net_device *ndev = platform_get_drvdata(pdev);

        if (ndev) {
                if (netif_running(ndev)) {
                        netif_device_detach(ndev);
                        smc_shutdown(ndev);
                        smc_phy_powerdown(ndev);
                }
        }
        return 0;
}

static int smc_drv_resume(struct device *dev)
{
        struct platform_device *pdev = to_platform_device(dev);
        struct net_device *ndev = platform_get_drvdata(pdev);

        if (ndev) {
                struct smc_local *lp = netdev_priv(ndev);
                smc_enable_device(pdev);
                if (netif_running(ndev)) {
                        smc_reset(ndev);
                        smc_enable(ndev);
                        if (lp->phy_type != 0)
                                smc_phy_configure(&lp->phy_configure);
                        netif_device_attach(ndev);
                }
        }
        return 0;
}

static struct dev_pm_ops smc_drv_pm_ops = {
        .suspend        = smc_drv_suspend,
        .resume         = smc_drv_resume,
};

static struct platform_driver smc_driver = {
        .probe          = smc_drv_probe,
        .remove         = smc_drv_remove,
        .driver         = {
                .name   = CARDNAME,
                .pm     = &smc_drv_pm_ops,
                .of_match_table   = of_match_ptr(smc91x_match),
                .acpi_match_table = smc91x_acpi_match,
        },
};

module_platform_driver(smc_driver);