/* Low-level parallel-port routines for 8255-based PC-style hardware.
 *
 * Authors: Phil Blundell <philb@gnu.org>
 *          Tim Waugh <tim@cyberelk.demon.co.uk>
 *          Jose Renau <renau@acm.org>
 *          David Campbell
 *          Andrea Arcangeli
 *
 * based on work by Grant Guenther <grant@torque.net> and Phil Blundell.
 *
 * Cleaned up include files - Russell King <linux@arm.uk.linux.org>
 * DMA support - Bert De Jonghe <bert@sophis.be>
 * Many ECP bugs fixed.  Fred Barnes & Jamie Lokier, 1999
 * More PCI support now conditional on CONFIG_PCI, 03/2001, Paul G.
 * Various hacks, Fred Barnes, 04/2001
 * Updated probing logic - Adam Belay <ambx1@neo.rr.com>
 */

/* This driver should work with any hardware that is broadly compatible
 * with that in the IBM PC.  This applies to the majority of integrated
 * I/O chipsets that are commonly available.  The expected register
 * layout is:
 *
 *      base+0          data
 *      base+1          status
 *      base+2          control
 *
 * In addition, there are some optional registers:
 *
 *      base+3          EPP address
 *      base+4          EPP data
 *      base+0x400      ECP config A
 *      base+0x401      ECP config B
 *      base+0x402      ECP control
 *
 * All registers are 8 bits wide and read/write.  If your hardware differs
 * only in register addresses (eg because your registers are on 32-bit
 * word boundaries) then you can alter the constants in parport_pc.h to
 * accommodate this.
 *
 * Note that the ECP registers may not start at offset 0x400 for PCI cards,
 * but rather will start at port->base_hi.
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/sched.h>
#include <linux/delay.h>
#include <linux/errno.h>
#include <linux/interrupt.h>
#include <linux/ioport.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/dma-mapping.h>
#include <linux/pci.h>
#include <linux/pnp.h>
#include <linux/platform_device.h>
#include <linux/sysctl.h>
#include <linux/io.h>
#include <linux/uaccess.h>

#include <asm/dma.h>

#include <linux/parport.h>
#include <linux/parport_pc.h>
#include <linux/via.h>
#include <asm/parport.h>

#define PARPORT_PC_MAX_PORTS PARPORT_MAX

#ifdef CONFIG_ISA_DMA_API
#define HAS_DMA
#endif

/* ECR modes */
#define ECR_SPP 00
#define ECR_PS2 01
#define ECR_PPF 02
#define ECR_ECP 03
#define ECR_EPP 04
#define ECR_VND 05
#define ECR_TST 06
#define ECR_CNF 07
#define ECR_MODE_MASK 0xe0
#define ECR_WRITE(p, v) frob_econtrol((p), 0xff, (v))

#undef DEBUG

#ifdef DEBUG
#define DPRINTK  printk
#else
#define DPRINTK(stuff...)
#endif


#define NR_SUPERIOS 3
static struct superio_struct {  /* For Super-IO chips autodetection */
        int io;
        int irq;
        int dma;
} superios[NR_SUPERIOS] = { {0,},};

static int user_specified;
#if defined(CONFIG_PARPORT_PC_SUPERIO) || \
       (defined(CONFIG_PARPORT_1284) && defined(CONFIG_PARPORT_PC_FIFO))
static int verbose_probing;
#endif
static int pci_registered_parport;
static int pnp_registered_parport;

/* frob_control, but for ECR */
static void frob_econtrol(struct parport *pb, unsigned char m,
                           unsigned char v)
{
        unsigned char ectr = 0;

        if (m != 0xff)
                ectr = inb(ECONTROL(pb));

        DPRINTK(KERN_DEBUG "frob_econtrol(%02x,%02x): %02x -> %02x\n",
                m, v, ectr, (ectr & ~m) ^ v);

        outb((ectr & ~m) ^ v, ECONTROL(pb));
}

static inline void frob_set_mode(struct parport *p, int mode)
{
        frob_econtrol(p, ECR_MODE_MASK, mode << 5);
}

#ifdef CONFIG_PARPORT_PC_FIFO
/* Safely change the mode bits in the ECR
   Returns:
            0    : Success
           -EBUSY: Could not drain FIFO in some finite amount of time,
                   mode not changed!
 */
static int change_mode(struct parport *p, int m)
{
        const struct parport_pc_private *priv = p->physport->private_data;
        unsigned char oecr;
        int mode;

        DPRINTK(KERN_INFO "parport change_mode ECP-ISA to mode 0x%02x\n", m);

        if (!priv->ecr) {
                printk(KERN_DEBUG "change_mode: but there's no ECR!\n");
                return 0;
        }

        /* Bits <7:5> contain the mode. */
        oecr = inb(ECONTROL(p));
        mode = (oecr >> 5) & 0x7;
        if (mode == m)
                return 0;

        if (mode >= 2 && !(priv->ctr & 0x20)) {
                /* This mode resets the FIFO, so we may
                 * have to wait for it to drain first. */
                unsigned long expire = jiffies + p->physport->cad->timeout;
                int counter;
                switch (mode) {
                case ECR_PPF: /* Parallel Port FIFO mode */
                case ECR_ECP: /* ECP Parallel Port mode */
                        /* Busy wait for 200us */
                        for (counter = 0; counter < 40; counter++) {
                                if (inb(ECONTROL(p)) & 0x01)
                                        break;
                                if (signal_pending(current))
                                        break;
                                udelay(5);
                        }

                        /* Poll slowly. */
                        while (!(inb(ECONTROL(p)) & 0x01)) {
                                if (time_after_eq(jiffies, expire))
                                        /* The FIFO is stuck. */
                                        return -EBUSY;
                                schedule_timeout_interruptible(
                                                        msecs_to_jiffies(10));
                                if (signal_pending(current))
                                        break;
                        }
                }
        }

        if (mode >= 2 && m >= 2) {
                /* We have to go through mode 001 */
                oecr &= ~(7 << 5);
                oecr |= ECR_PS2 << 5;
                ECR_WRITE(p, oecr);
        }

        /* Set the mode. */
        oecr &= ~(7 << 5);
        oecr |= m << 5;
        ECR_WRITE(p, oecr);
        return 0;
}

#ifdef CONFIG_PARPORT_1284
/* Find FIFO lossage; FIFO is reset */
#if 0
static int get_fifo_residue(struct parport *p)
{
        int residue;
        int cnfga;
        const struct parport_pc_private *priv = p->physport->private_data;

        /* Adjust for the contents of the FIFO. */
        for (residue = priv->fifo_depth; ; residue--) {
                if (inb(ECONTROL(p)) & 0x2)
                                /* Full up. */
                        break;

                outb(0, FIFO(p));
        }

        printk(KERN_DEBUG "%s: %d PWords were left in FIFO\n", p->name,
                residue);

        /* Reset the FIFO. */
        frob_set_mode(p, ECR_PS2);

        /* Now change to config mode and clean up. FIXME */
        frob_set_mode(p, ECR_CNF);
        cnfga = inb(CONFIGA(p));
        printk(KERN_DEBUG "%s: cnfgA contains 0x%02x\n", p->name, cnfga);

        if (!(cnfga & (1<<2))) {
                printk(KERN_DEBUG "%s: Accounting for extra byte\n", p->name);
                residue++;
        }

        /* Don't care about partial PWords until support is added for
         * PWord != 1 byte. */

        /* Back to PS2 mode. */
        frob_set_mode(p, ECR_PS2);

        DPRINTK(KERN_DEBUG
             "*** get_fifo_residue: done residue collecting (ecr = 0x%2.2x)\n",
                                                        inb(ECONTROL(p)));
        return residue;
}
#endif  /*  0 */
#endif /* IEEE 1284 support */
#endif /* FIFO support */

/*
 * Clear TIMEOUT BIT in EPP MODE
 *
 * This is also used in SPP detection.
 */
static int clear_epp_timeout(struct parport *pb)
{
        unsigned char r;

        if (!(parport_pc_read_status(pb) & 0x01))
                return 1;

        /* To clear timeout some chips require double read */
        parport_pc_read_status(pb);
        r = parport_pc_read_status(pb);
        outb(r | 0x01, STATUS(pb)); /* Some reset by writing 1 */
        outb(r & 0xfe, STATUS(pb)); /* Others by writing 0 */
        r = parport_pc_read_status(pb);

        return !(r & 0x01);
}

/*
 * Access functions.
 *
 * Most of these aren't static because they may be used by the
 * parport_xxx_yyy macros.  extern __inline__ versions of several
 * of these are in parport_pc.h.
 */

static void parport_pc_init_state(struct pardevice *dev,
                                                struct parport_state *s)
{
        s->u.pc.ctr = 0xc;
        if (dev->irq_func &&
            dev->port->irq != PARPORT_IRQ_NONE)
                /* Set ackIntEn */
                s->u.pc.ctr |= 0x10;

        s->u.pc.ecr = 0x34; /* NetMos chip can cause problems 0x24;
                             * D.Gruszka VScom */
}

static void parport_pc_save_state(struct parport *p, struct parport_state *s)
{
        const struct parport_pc_private *priv = p->physport->private_data;
        s->u.pc.ctr = priv->ctr;
        if (priv->ecr)
                s->u.pc.ecr = inb(ECONTROL(p));
}

static void parport_pc_restore_state(struct parport *p,
                                                struct parport_state *s)
{
        struct parport_pc_private *priv = p->physport->private_data;
        register unsigned char c = s->u.pc.ctr & priv->ctr_writable;
        outb(c, CONTROL(p));
        priv->ctr = c;
        if (priv->ecr)
                ECR_WRITE(p, s->u.pc.ecr);
}

#ifdef CONFIG_PARPORT_1284
static size_t parport_pc_epp_read_data(struct parport *port, void *buf,
                                       size_t length, int flags)
{
        size_t got = 0;

        if (flags & PARPORT_W91284PIC) {
                unsigned char status;
                size_t left = length;

                /* use knowledge about data lines..:
                 *  nFault is 0 if there is at least 1 byte in the Warp's FIFO
                 *  pError is 1 if there are 16 bytes in the Warp's FIFO
                 */
                status = inb(STATUS(port));

                while (!(status & 0x08) && got < length) {
                        if (left >= 16 && (status & 0x20) && !(status & 0x08)) {
                                /* can grab 16 bytes from warp fifo */
                                if (!((long)buf & 0x03))
                                        insl(EPPDATA(port), buf, 4);
                                else
                                        insb(EPPDATA(port), buf, 16);
                                buf += 16;
                                got += 16;
                                left -= 16;
                        } else {
                                /* grab single byte from the warp fifo */
                                *((char *)buf) = inb(EPPDATA(port));
                                buf++;
                                got++;
                                left--;
                        }
                        status = inb(STATUS(port));
                        if (status & 0x01) {
                                /* EPP timeout should never occur... */
                                printk(KERN_DEBUG
"%s: EPP timeout occurred while talking to w91284pic (should not have done)\n", port->name);
                                clear_epp_timeout(port);
                        }
                }
                return got;
        }
        if ((flags & PARPORT_EPP_FAST) && (length > 1)) {
                if (!(((long)buf | length) & 0x03))
                        insl(EPPDATA(port), buf, (length >> 2));
                else
                        insb(EPPDATA(port), buf, length);
                if (inb(STATUS(port)) & 0x01) {
                        clear_epp_timeout(port);
                        return -EIO;
                }
                return length;
        }
        for (; got < length; got++) {
                *((char *)buf) = inb(EPPDATA(port));
                buf++;
                if (inb(STATUS(port)) & 0x01) {
                        /* EPP timeout */
                        clear_epp_timeout(port);
                        break;
                }
        }

        return got;
}

static size_t parport_pc_epp_write_data(struct parport *port, const void *buf,
                                        size_t length, int flags)
{
        size_t written = 0;

        if ((flags & PARPORT_EPP_FAST) && (length > 1)) {
                if (!(((long)buf | length) & 0x03))
                        outsl(EPPDATA(port), buf, (length >> 2));
                else
                        outsb(EPPDATA(port), buf, length);
                if (inb(STATUS(port)) & 0x01) {
                        clear_epp_timeout(port);
                        return -EIO;
                }
                return length;
        }
        for (; written < length; written++) {
                outb(*((char *)buf), EPPDATA(port));
                buf++;
                if (inb(STATUS(port)) & 0x01) {
                        clear_epp_timeout(port);
                        break;
                }
        }

        return written;
}

static size_t parport_pc_epp_read_addr(struct parport *port, void *buf,
                                        size_t length, int flags)
{
        size_t got = 0;

        if ((flags & PARPORT_EPP_FAST) && (length > 1)) {
                insb(EPPADDR(port), buf, length);
                if (inb(STATUS(port)) & 0x01) {
                        clear_epp_timeout(port);
                        return -EIO;
                }
                return length;
        }
        for (; got < length; got++) {
                *((char *)buf) = inb(EPPADDR(port));
                buf++;
                if (inb(STATUS(port)) & 0x01) {
                        clear_epp_timeout(port);
                        break;
                }
        }

        return got;
}

static size_t parport_pc_epp_write_addr(struct parport *port,
                                         const void *buf, size_t length,
                                         int flags)
{
        size_t written = 0;

        if ((flags & PARPORT_EPP_FAST) && (length > 1)) {
                outsb(EPPADDR(port), buf, length);
                if (inb(STATUS(port)) & 0x01) {
                        clear_epp_timeout(port);
                        return -EIO;
                }
                return length;
        }
        for (; written < length; written++) {
                outb(*((char *)buf), EPPADDR(port));
                buf++;
                if (inb(STATUS(port)) & 0x01) {
                        clear_epp_timeout(port);
                        break;
                }
        }

        return written;
}

static size_t parport_pc_ecpepp_read_data(struct parport *port, void *buf,
                                          size_t length, int flags)
{
        size_t got;

        frob_set_mode(port, ECR_EPP);
        parport_pc_data_reverse(port);
        parport_pc_write_control(port, 0x4);
        got = parport_pc_epp_read_data(port, buf, length, flags);
        frob_set_mode(port, ECR_PS2);

        return got;
}

static size_t parport_pc_ecpepp_write_data(struct parport *port,
                                           const void *buf, size_t length,
                                           int flags)
{
        size_t written;

        frob_set_mode(port, ECR_EPP);
        parport_pc_write_control(port, 0x4);
        parport_pc_data_forward(port);
        written = parport_pc_epp_write_data(port, buf, length, flags);
        frob_set_mode(port, ECR_PS2);

        return written;
}

static size_t parport_pc_ecpepp_read_addr(struct parport *port, void *buf,
                                          size_t length, int flags)
{
        size_t got;

        frob_set_mode(port, ECR_EPP);
        parport_pc_data_reverse(port);
        parport_pc_write_control(port, 0x4);
        got = parport_pc_epp_read_addr(port, buf, length, flags);
        frob_set_mode(port, ECR_PS2);

        return got;
}

static size_t parport_pc_ecpepp_write_addr(struct parport *port,
                                            const void *buf, size_t length,
                                            int flags)
{
        size_t written;

        frob_set_mode(port, ECR_EPP);
        parport_pc_write_control(port, 0x4);
        parport_pc_data_forward(port);
        written = parport_pc_epp_write_addr(port, buf, length, flags);
        frob_set_mode(port, ECR_PS2);

        return written;
}
#endif /* IEEE 1284 support */

#ifdef CONFIG_PARPORT_PC_FIFO
static size_t parport_pc_fifo_write_block_pio(struct parport *port,
                                               const void *buf, size_t length)
{
        int ret = 0;
        const unsigned char *bufp = buf;
        size_t left = length;
        unsigned long expire = jiffies + port->physport->cad->timeout;
        const int fifo = FIFO(port);
        int poll_for = 8; /* 80 usecs */
        const struct parport_pc_private *priv = port->physport->private_data;
        const int fifo_depth = priv->fifo_depth;

        port = port->physport;

        /* We don't want to be interrupted every character. */
        parport_pc_disable_irq(port);
        /* set nErrIntrEn and serviceIntr */
        frob_econtrol(port, (1<<4) | (1<<2), (1<<4) | (1<<2));

        /* Forward mode. */
        parport_pc_data_forward(port); /* Must be in PS2 mode */

        while (left) {
                unsigned char byte;
                unsigned char ecrval = inb(ECONTROL(port));
                int i = 0;

                if (need_resched() && time_before(jiffies, expire))
                        /* Can't yield the port. */
                        schedule();

                /* Anyone else waiting for the port? */
                if (port->waithead) {
                        printk(KERN_DEBUG "Somebody wants the port\n");
                        break;
                }

                if (ecrval & 0x02) {
                        /* FIFO is full. Wait for interrupt. */

                        /* Clear serviceIntr */
                        ECR_WRITE(port, ecrval & ~(1<<2));
false_alarm:
                        ret = parport_wait_event(port, HZ);
                        if (ret < 0)
                                break;
                        ret = 0;
                        if (!time_before(jiffies, expire)) {
                                /* Timed out. */
                                printk(KERN_DEBUG "FIFO write timed out\n");
                                break;
                        }
                        ecrval = inb(ECONTROL(port));
                        if (!(ecrval & (1<<2))) {
                                if (need_resched() &&
                                    time_before(jiffies, expire))
                                        schedule();

                                goto false_alarm;
                        }

                        continue;
                }

                /* Can't fail now. */
                expire = jiffies + port->cad->timeout;

poll:
                if (signal_pending(current))
                        break;

                if (ecrval & 0x01) {
                        /* FIFO is empty. Blast it full. */
                        const int n = left < fifo_depth ? left : fifo_depth;
                        outsb(fifo, bufp, n);
                        bufp += n;
                        left -= n;

                        /* Adjust the poll time. */
                        if (i < (poll_for - 2))
                                poll_for--;
                        continue;
                } else if (i++ < poll_for) {
                        udelay(10);
                        ecrval = inb(ECONTROL(port));
                        goto poll;
                }

                /* Half-full(call me an optimist) */
                byte = *bufp++;
                outb(byte, fifo);
                left--;
        }
        dump_parport_state("leave fifo_write_block_pio", port);
        return length - left;
}

#ifdef HAS_DMA
static size_t parport_pc_fifo_write_block_dma(struct parport *port,
                                               const void *buf, size_t length)
{
        int ret = 0;
        unsigned long dmaflag;
        size_t left = length;
        const struct parport_pc_private *priv = port->physport->private_data;
        struct device *dev = port->physport->dev;
        dma_addr_t dma_addr, dma_handle;
        size_t maxlen = 0x10000; /* max 64k per DMA transfer */
        unsigned long start = (unsigned long) buf;
        unsigned long end = (unsigned long) buf + length - 1;

        dump_parport_state("enter fifo_write_block_dma", port);
        if (end < MAX_DMA_ADDRESS) {
                /* If it would cross a 64k boundary, cap it at the end. */
                if ((start ^ end) & ~0xffffUL)
                        maxlen = 0x10000 - (start & 0xffff);

                dma_addr = dma_handle = dma_map_single(dev, (void *)buf, length,
                                                       DMA_TO_DEVICE);
        } else {
                /* above 16 MB we use a bounce buffer as ISA-DMA
                   is not possible */
                maxlen   = PAGE_SIZE;          /* sizeof(priv->dma_buf) */
                dma_addr = priv->dma_handle;
                dma_handle = 0;
        }

        port = port->physport;

        /* We don't want to be interrupted every character. */
        parport_pc_disable_irq(port);
        /* set nErrIntrEn and serviceIntr */
        frob_econtrol(port, (1<<4) | (1<<2), (1<<4) | (1<<2));

        /* Forward mode. */
        parport_pc_data_forward(port); /* Must be in PS2 mode */

        while (left) {
                unsigned long expire = jiffies + port->physport->cad->timeout;

                size_t count = left;

                if (count > maxlen)
                        count = maxlen;

                if (!dma_handle)   /* bounce buffer ! */
                        memcpy(priv->dma_buf, buf, count);

                dmaflag = claim_dma_lock();
                disable_dma(port->dma);
                clear_dma_ff(port->dma);
                set_dma_mode(port->dma, DMA_MODE_WRITE);
                set_dma_addr(port->dma, dma_addr);
                set_dma_count(port->dma, count);

                /* Set DMA mode */
                frob_econtrol(port, 1<<3, 1<<3);

                /* Clear serviceIntr */
                frob_econtrol(port, 1<<2, 0);

                enable_dma(port->dma);
                release_dma_lock(dmaflag);

                /* assume DMA will be successful */
                left -= count;
                buf  += count;
                if (dma_handle)
                        dma_addr += count;

                /* Wait for interrupt. */
false_alarm:
                ret = parport_wait_event(port, HZ);
                if (ret < 0)
                        break;
                ret = 0;
                if (!time_before(jiffies, expire)) {
                        /* Timed out. */
                        printk(KERN_DEBUG "DMA write timed out\n");
                        break;
                }
                /* Is serviceIntr set? */
                if (!(inb(ECONTROL(port)) & (1<<2))) {
                        cond_resched();

                        goto false_alarm;
                }

                dmaflag = claim_dma_lock();
                disable_dma(port->dma);
                clear_dma_ff(port->dma);
                count = get_dma_residue(port->dma);
                release_dma_lock(dmaflag);

                cond_resched(); /* Can't yield the port. */

                /* Anyone else waiting for the port? */
                if (port->waithead) {
                        printk(KERN_DEBUG "Somebody wants the port\n");
                        break;
                }

                /* update for possible DMA residue ! */
                buf  -= count;
                left += count;
                if (dma_handle)
                        dma_addr -= count;
        }

        /* Maybe got here through break, so adjust for DMA residue! */
        dmaflag = claim_dma_lock();
        disable_dma(port->dma);
        clear_dma_ff(port->dma);
        left += get_dma_residue(port->dma);
        release_dma_lock(dmaflag);

        /* Turn off DMA mode */
        frob_econtrol(port, 1<<3, 0);

        if (dma_handle)
                dma_unmap_single(dev, dma_handle, length, DMA_TO_DEVICE);

        dump_parport_state("leave fifo_write_block_dma", port);
        return length - left;
}
#endif

static inline size_t parport_pc_fifo_write_block(struct parport *port,
                                               const void *buf, size_t length)
{
#ifdef HAS_DMA
        if (port->dma != PARPORT_DMA_NONE)
                return parport_pc_fifo_write_block_dma(port, buf, length);
#endif
        return parport_pc_fifo_write_block_pio(port, buf, length);
}

/* Parallel Port FIFO mode (ECP chipsets) */
static size_t parport_pc_compat_write_block_pio(struct parport *port,
                                                 const void *buf, size_t length,
                                                 int flags)
{
        size_t written;
        int r;
        unsigned long expire;
        const struct parport_pc_private *priv = port->physport->private_data;

        /* Special case: a timeout of zero means we cannot call schedule().
         * Also if O_NONBLOCK is set then use the default implementation. */
        if (port->physport->cad->timeout <= PARPORT_INACTIVITY_O_NONBLOCK)
                return parport_ieee1284_write_compat(port, buf,
                                                      length, flags);

        /* Set up parallel port FIFO mode.*/
        parport_pc_data_forward(port); /* Must be in PS2 mode */
        parport_pc_frob_control(port, PARPORT_CONTROL_STROBE, 0);
        r = change_mode(port, ECR_PPF); /* Parallel port FIFO */
        if (r)
                printk(KERN_DEBUG "%s: Warning change_mode ECR_PPF failed\n",
                                                                port->name);

        port->physport->ieee1284.phase = IEEE1284_PH_FWD_DATA;

        /* Write the data to the FIFO. */
        written = parport_pc_fifo_write_block(port, buf, length);

        /* Finish up. */
        /* For some hardware we don't want to touch the mode until
         * the FIFO is empty, so allow 4 seconds for each position
         * in the fifo.
         */
        expire = jiffies + (priv->fifo_depth * HZ * 4);
        do {
                /* Wait for the FIFO to empty */
                r = change_mode(port, ECR_PS2);
                if (r != -EBUSY)
                        break;
        } while (time_before(jiffies, expire));
        if (r == -EBUSY) {

                printk(KERN_DEBUG "%s: FIFO is stuck\n", port->name);

                /* Prevent further data transfer. */
                frob_set_mode(port, ECR_TST);

                /* Adjust for the contents of the FIFO. */
                for (written -= priv->fifo_depth; ; written++) {
                        if (inb(ECONTROL(port)) & 0x2) {
                                /* Full up. */
                                break;
                        }
                        outb(0, FIFO(port));
                }

                /* Reset the FIFO and return to PS2 mode. */
                frob_set_mode(port, ECR_PS2);
        }

        r = parport_wait_peripheral(port,
                                     PARPORT_STATUS_BUSY,
                                     PARPORT_STATUS_BUSY);
        if (r)
                printk(KERN_DEBUG
                        "%s: BUSY timeout (%d) in compat_write_block_pio\n",
                        port->name, r);

        port->physport->ieee1284.phase = IEEE1284_PH_FWD_IDLE;

        return written;
}

/* ECP */
#ifdef CONFIG_PARPORT_1284
static size_t parport_pc_ecp_write_block_pio(struct parport *port,
                                              const void *buf, size_t length,
                                              int flags)
{
        size_t written;
        int r;
        unsigned long expire;
        const struct parport_pc_private *priv = port->physport->private_data;

        /* Special case: a timeout of zero means we cannot call schedule().
         * Also if O_NONBLOCK is set then use the default implementation. */
        if (port->physport->cad->timeout <= PARPORT_INACTIVITY_O_NONBLOCK)
                return parport_ieee1284_ecp_write_data(port, buf,
                                                        length, flags);

        /* Switch to forward mode if necessary. */
        if (port->physport->ieee1284.phase != IEEE1284_PH_FWD_IDLE) {
                /* Event 47: Set nInit high. */
                parport_frob_control(port,
                                      PARPORT_CONTROL_INIT
                                      | PARPORT_CONTROL_AUTOFD,
                                      PARPORT_CONTROL_INIT
                                      | PARPORT_CONTROL_AUTOFD);

                /* Event 49: PError goes high. */
                r = parport_wait_peripheral(port,
                                             PARPORT_STATUS_PAPEROUT,
                                             PARPORT_STATUS_PAPEROUT);
                if (r) {
                        printk(KERN_DEBUG "%s: PError timeout (%d) "
                                "in ecp_write_block_pio\n", port->name, r);
                }
        }

        /* Set up ECP parallel port mode.*/
        parport_pc_data_forward(port); /* Must be in PS2 mode */
        parport_pc_frob_control(port,
                                 PARPORT_CONTROL_STROBE |
                                 PARPORT_CONTROL_AUTOFD,
                                 0);
        r = change_mode(port, ECR_ECP); /* ECP FIFO */
        if (r)
                printk(KERN_DEBUG "%s: Warning change_mode ECR_ECP failed\n",
                                                                port->name);
        port->physport->ieee1284.phase = IEEE1284_PH_FWD_DATA;

        /* Write the data to the FIFO. */
        written = parport_pc_fifo_write_block(port, buf, length);

        /* Finish up. */
        /* For some hardware we don't want to touch the mode until
         * the FIFO is empty, so allow 4 seconds for each position
         * in the fifo.
         */
        expire = jiffies + (priv->fifo_depth * (HZ * 4));
        do {
                /* Wait for the FIFO to empty */
                r = change_mode(port, ECR_PS2);
                if (r != -EBUSY)
                        break;
        } while (time_before(jiffies, expire));
        if (r == -EBUSY) {

                printk(KERN_DEBUG "%s: FIFO is stuck\n", port->name);

                /* Prevent further data transfer. */
                frob_set_mode(port, ECR_TST);

                /* Adjust for the contents of the FIFO. */
                for (written -= priv->fifo_depth; ; written++) {
                        if (inb(ECONTROL(port)) & 0x2) {
                                /* Full up. */
                                break;
                        }
                        outb(0, FIFO(port));
                }

                /* Reset the FIFO and return to PS2 mode. */
                frob_set_mode(port, ECR_PS2);

                /* Host transfer recovery. */
                parport_pc_data_reverse(port); /* Must be in PS2 mode */
                udelay(5);
                parport_frob_control(port, PARPORT_CONTROL_INIT, 0);
                r = parport_wait_peripheral(port, PARPORT_STATUS_PAPEROUT, 0);
                if (r)
                        printk(KERN_DEBUG "%s: PE,1 timeout (%d) "
                                "in ecp_write_block_pio\n", port->name, r);

                parport_frob_control(port,
                                      PARPORT_CONTROL_INIT,
                                      PARPORT_CONTROL_INIT);
                r = parport_wait_peripheral(port,
                                             PARPORT_STATUS_PAPEROUT,
                                             PARPORT_STATUS_PAPEROUT);
                if (r)
                        printk(KERN_DEBUG "%s: PE,2 timeout (%d) "
                                "in ecp_write_block_pio\n", port->name, r);
        }

        r = parport_wait_peripheral(port,
                                     PARPORT_STATUS_BUSY,
                                     PARPORT_STATUS_BUSY);
        if (r)
                printk(KERN_DEBUG
                        "%s: BUSY timeout (%d) in ecp_write_block_pio\n",
                        port->name, r);

        port->physport->ieee1284.phase = IEEE1284_PH_FWD_IDLE;

        return written;
}

#if 0
static size_t parport_pc_ecp_read_block_pio(struct parport *port,
                                             void *buf, size_t length,
                                             int flags)
{
        size_t left = length;
        size_t fifofull;
        int r;
        const int fifo = FIFO(port);
        const struct parport_pc_private *priv = port->physport->private_data;
        const int fifo_depth = priv->fifo_depth;
        char *bufp = buf;

        port = port->physport;
        DPRINTK(KERN_DEBUG "parport_pc: parport_pc_ecp_read_block_pio\n");
        dump_parport_state("enter fcn", port);

        /* Special case: a timeout of zero means we cannot call schedule().
         * Also if O_NONBLOCK is set then use the default implementation. */
        if (port->cad->timeout <= PARPORT_INACTIVITY_O_NONBLOCK)
                return parport_ieee1284_ecp_read_data(port, buf,
                                                       length, flags);

        if (port->ieee1284.mode == IEEE1284_MODE_ECPRLE) {
                /* If the peripheral is allowed to send RLE compressed
                 * data, it is possible for a byte to expand to 128
                 * bytes in the FIFO. */
                fifofull = 128;
        } else {
                fifofull = fifo_depth;
        }

        /* If the caller wants less than a full FIFO's worth of data,
         * go through software emulation.  Otherwise we may have to throw
         * away data. */
        if (length < fifofull)
                return parport_ieee1284_ecp_read_data(port, buf,
                                                       length, flags);

        if (port->ieee1284.phase != IEEE1284_PH_REV_IDLE) {
                /* change to reverse-idle phase (must be in forward-idle) */

                /* Event 38: Set nAutoFd low (also make sure nStrobe is high) */
                parport_frob_control(port,
                                      PARPORT_CONTROL_AUTOFD
                                      | PARPORT_CONTROL_STROBE,
                                      PARPORT_CONTROL_AUTOFD);
                parport_pc_data_reverse(port); /* Must be in PS2 mode */
                udelay(5);
                /* Event 39: Set nInit low to initiate bus reversal */
                parport_frob_control(port,
                                      PARPORT_CONTROL_INIT,
                                      0);
                /* Event 40: Wait for  nAckReverse (PError) to go low */
                r = parport_wait_peripheral(port, PARPORT_STATUS_PAPEROUT, 0);
                if (r) {
                        printk(KERN_DEBUG "%s: PE timeout Event 40 (%d) "

                                "in ecp_read_block_pio\n", port->name, r);
                        return 0;
                }
        }

        /* Set up ECP FIFO mode.*/
/*      parport_pc_frob_control(port,
                                 PARPORT_CONTROL_STROBE |
                                 PARPORT_CONTROL_AUTOFD,
                                 PARPORT_CONTROL_AUTOFD); */
        r = change_mode(port, ECR_ECP); /* ECP FIFO */
        if (r)
                printk(KERN_DEBUG "%s: Warning change_mode ECR_ECP failed\n",
                                                                port->name);

        port->ieee1284.phase = IEEE1284_PH_REV_DATA;

        /* the first byte must be collected manually */
        dump_parport_state("pre 43", port);
        /* Event 43: Wait for nAck to go low */
        r = parport_wait_peripheral(port, PARPORT_STATUS_ACK, 0);
        if (r) {
                /* timed out while reading -- no data */
                printk(KERN_DEBUG "PIO read timed out (initial byte)\n");
                goto out_no_data;
        }
        /* read byte */
        *bufp++ = inb(DATA(port));
        left--;
        dump_parport_state("43-44", port);
        /* Event 44: nAutoFd (HostAck) goes high to acknowledge */
        parport_pc_frob_control(port,
                                 PARPORT_CONTROL_AUTOFD,
                                 0);
        dump_parport_state("pre 45", port);
        /* Event 45: Wait for nAck to go high */
        /* r = parport_wait_peripheral(port, PARPORT_STATUS_ACK,
                                                PARPORT_STATUS_ACK); */
        dump_parport_state("post 45", port);
        r = 0;
        if (r) {
                /* timed out while waiting for peripheral to respond to ack */
                printk(KERN_DEBUG "ECP PIO read timed out (waiting for nAck)\n");

                /* keep hold of the byte we've got already */
                goto out_no_data;
        }
        /* Event 46: nAutoFd (HostAck) goes low to accept more data */
        parport_pc_frob_control(port,
                                 PARPORT_CONTROL_AUTOFD,
                                 PARPORT_CONTROL_AUTOFD);


        dump_parport_state("rev idle", port);
        /* Do the transfer. */
        while (left > fifofull) {
                int ret;
                unsigned long expire = jiffies + port->cad->timeout;
                unsigned char ecrval = inb(ECONTROL(port));

                if (need_resched() && time_before(jiffies, expire))
                        /* Can't yield the port. */
                        schedule();

                /* At this point, the FIFO may already be full. In
                 * that case ECP is already holding back the
                 * peripheral (assuming proper design) with a delayed
                 * handshake.  Work fast to avoid a peripheral
                 * timeout.  */

                if (ecrval & 0x01) {
                        /* FIFO is empty. Wait for interrupt. */
                        dump_parport_state("FIFO empty", port);

                        /* Anyone else waiting for the port? */
                        if (port->waithead) {
                                printk(KERN_DEBUG "Somebody wants the port\n");
                                break;
                        }

                        /* Clear serviceIntr */
                        ECR_WRITE(port, ecrval & ~(1<<2));
false_alarm:
                        dump_parport_state("waiting", port);
                        ret = parport_wait_event(port, HZ);
                        DPRINTK(KERN_DEBUG "parport_wait_event returned %d\n",
                                                                        ret);
                        if (ret < 0)
                                break;
                        ret = 0;
                        if (!time_before(jiffies, expire)) {
                                /* Timed out. */
                                dump_parport_state("timeout", port);
                                printk(KERN_DEBUG "PIO read timed out\n");
                                break;
                        }
                        ecrval = inb(ECONTROL(port));
                        if (!(ecrval & (1<<2))) {
                                if (need_resched() &&
                                    time_before(jiffies, expire)) {
                                        schedule();
                                }
                                goto false_alarm;
                        }

                        /* Depending on how the FIFO threshold was
                         * set, how long interrupt service took, and
                         * how fast the peripheral is, we might be
                         * lucky and have a just filled FIFO. */
                        continue;
                }

                if (ecrval & 0x02) {
                        /* FIFO is full. */
                        dump_parport_state("FIFO full", port);
                        insb(fifo, bufp, fifo_depth);
                        bufp += fifo_depth;
                        left -= fifo_depth;
                        continue;
                }

                DPRINTK(KERN_DEBUG
                  "*** ecp_read_block_pio: reading one byte from the FIFO\n");

                /* FIFO not filled.  We will cycle this loop for a while
                 * and either the peripheral will fill it faster,
                 * tripping a fast empty with insb, or we empty it. */
                *bufp++ = inb(fifo);
                left--;
        }

        /* scoop up anything left in the FIFO */
        while (left && !(inb(ECONTROL(port) & 0x01))) {
                *bufp++ = inb(fifo);
                left--;
        }

        port->ieee1284.phase = IEEE1284_PH_REV_IDLE;
        dump_parport_state("rev idle2", port);

out_no_data:

        /* Go to forward idle mode to shut the peripheral up (event 47). */
        parport_frob_control(port, PARPORT_CONTROL_INIT, PARPORT_CONTROL_INIT);

        /* event 49: PError goes high */
        r = parport_wait_peripheral(port,
                                     PARPORT_STATUS_PAPEROUT,
                                     PARPORT_STATUS_PAPEROUT);
        if (r) {
                printk(KERN_DEBUG
                        "%s: PE timeout FWDIDLE (%d) in ecp_read_block_pio\n",
                        port->name, r);
        }

        port->ieee1284.phase = IEEE1284_PH_FWD_IDLE;

        /* Finish up. */
        {
                int lost = get_fifo_residue(port);
                if (lost)
                        /* Shouldn't happen with compliant peripherals. */
                        printk(KERN_DEBUG "%s: DATA LOSS (%d bytes)!\n",
                                port->name, lost);
        }

        dump_parport_state("fwd idle", port);
        return length - left;
}
#endif  /*  0  */
#endif /* IEEE 1284 support */
#endif /* Allowed to use FIFO/DMA */


/*
 *      ******************************************
 *      INITIALISATION AND MODULE STUFF BELOW HERE
 *      ******************************************
 */

/* GCC is not inlining extern inline function later overwriten to non-inline,
   so we use outlined_ variants here.  */
static const struct parport_operations parport_pc_ops = {
        .write_data     = parport_pc_write_data,
        .read_data      = parport_pc_read_data,

        .write_control  = parport_pc_write_control,
        .read_control   = parport_pc_read_control,
        .frob_control   = parport_pc_frob_control,

        .read_status    = parport_pc_read_status,

        .enable_irq     = parport_pc_enable_irq,
        .disable_irq    = parport_pc_disable_irq,

        .data_forward   = parport_pc_data_forward,
        .data_reverse   = parport_pc_data_reverse,

        .init_state     = parport_pc_init_state,
        .save_state     = parport_pc_save_state,
        .restore_state  = parport_pc_restore_state,

        .epp_write_data = parport_ieee1284_epp_write_data,
        .epp_read_data  = parport_ieee1284_epp_read_data,
        .epp_write_addr = parport_ieee1284_epp_write_addr,
        .epp_read_addr  = parport_ieee1284_epp_read_addr,

        .ecp_write_data = parport_ieee1284_ecp_write_data,
        .ecp_read_data  = parport_ieee1284_ecp_read_data,
        .ecp_write_addr = parport_ieee1284_ecp_write_addr,

        .compat_write_data      = parport_ieee1284_write_compat,
        .nibble_read_data       = parport_ieee1284_read_nibble,
        .byte_read_data         = parport_ieee1284_read_byte,

        .owner          = THIS_MODULE,
};

#ifdef CONFIG_PARPORT_PC_SUPERIO

static struct superio_struct *find_free_superio(void)
{
        int i;
        for (i = 0; i < NR_SUPERIOS; i++)
                if (superios[i].io == 0)
                        return &superios[i];
        return NULL;
}


/* Super-IO chipset detection, Winbond, SMSC */
static void __devinit show_parconfig_smsc37c669(int io, int key)
{
        int cr1, cr4, cra, cr23, cr26, cr27;
        struct superio_struct *s;

        static const char *const modes[] = {
                "SPP and Bidirectional (PS/2)",
                "EPP and SPP",
                "ECP",
                "ECP and EPP" };

        outb(key, io);
        outb(key, io);
        outb(1, io);
        cr1 = inb(io + 1);
        outb(4, io);
        cr4 = inb(io + 1);
        outb(0x0a, io);
        cra = inb(io + 1);
        outb(0x23, io);
        cr23 = inb(io + 1);
        outb(0x26, io);
        cr26 = inb(io + 1);
        outb(0x27, io);
        cr27 = inb(io + 1);
        outb(0xaa, io);

        if (verbose_probing) {
                printk(KERN_INFO
                        "SMSC 37c669 LPT Config: cr_1=0x%02x, 4=0x%02x, "
                        "A=0x%2x, 23=0x%02x, 26=0x%02x, 27=0x%02x\n",
                        cr1, cr4, cra, cr23, cr26, cr27);

                /* The documentation calls DMA and IRQ-Lines by letters, so
                   the board maker can/will wire them
                   appropriately/randomly...  G=reserved H=IDE-irq, */
                printk(KERN_INFO
        "SMSC LPT Config: io=0x%04x, irq=%c, dma=%c, fifo threshold=%d\n",
                                cr23 * 4,
                                (cr27 & 0x0f) ? 'A' - 1 + (cr27 & 0x0f) : '-',
                                (cr26 & 0x0f) ? 'A' - 1 + (cr26 & 0x0f) : '-',
                                cra & 0x0f);
                printk(KERN_INFO "SMSC LPT Config: enabled=%s power=%s\n",
                       (cr23 * 4 >= 0x100) ? "yes" : "no",
                       (cr1 & 4) ? "yes" : "no");
                printk(KERN_INFO
                        "SMSC LPT Config: Port mode=%s, EPP version =%s\n",
                                (cr1 & 0x08) ? "Standard mode only (SPP)"
                                              : modes[cr4 & 0x03],
                                (cr4 & 0x40) ? "1.7" : "1.9");
        }

        /* Heuristics !  BIOS setup for this mainboard device limits
           the choices to standard settings, i.e. io-address and IRQ
           are related, however DMA can be 1 or 3, assume DMA_A=DMA1,
           DMA_C=DMA3 (this is true e.g. for TYAN 1564D Tomcat IV) */
        if (cr23 * 4 >= 0x100) { /* if active */
                s = find_free_superio();
                if (s == NULL)
                        printk(KERN_INFO "Super-IO: too many chips!\n");
                else {
                        int d;
                        switch (cr23 * 4) {
                        case 0x3bc:
                                s->io = 0x3bc;
                                s->irq = 7;
                                break;
                        case 0x378:
                                s->io = 0x378;
                                s->irq = 7;
                                break;
                        case 0x278:
                                s->io = 0x278;
                                s->irq = 5;
                        }
                        d = (cr26 & 0x0f);
                        if (d == 1 || d == 3)
                                s->dma = d;
                        else
                                s->dma = PARPORT_DMA_NONE;
                }
        }
}


static void __devinit show_parconfig_winbond(int io, int key)
{
        int cr30, cr60, cr61, cr70, cr74, crf0;
        struct superio_struct *s;
        static const char *const modes[] = {
                "Standard (SPP) and Bidirectional(PS/2)", /* 0 */
                "EPP-1.9 and SPP",
                "ECP",
                "ECP and EPP-1.9",
                "Standard (SPP)",
                "EPP-1.7 and SPP",              /* 5 */
                "undefined!",
                "ECP and EPP-1.7" };
        static char *const irqtypes[] = {
                "pulsed low, high-Z",
                "follows nACK" };

        /* The registers are called compatible-PnP because the
           register layout is modelled after ISA-PnP, the access
           method is just another ... */
        outb(key, io);
        outb(key, io);
        outb(0x07, io);   /* Register 7: Select Logical Device */
        outb(0x01, io + 1); /* LD1 is Parallel Port */
        outb(0x30, io);
        cr30 = inb(io + 1);
        outb(0x60, io);
        cr60 = inb(io + 1);
        outb(0x61, io);
        cr61 = inb(io + 1);
        outb(0x70, io);
        cr70 = inb(io + 1);
        outb(0x74, io);
        cr74 = inb(io + 1);
        outb(0xf0, io);
        crf0 = inb(io + 1);
        outb(0xaa, io);

        if (verbose_probing) {
                printk(KERN_INFO
    "Winbond LPT Config: cr_30=%02x 60,61=%02x%02x 70=%02x 74=%02x, f0=%02x\n",
                                        cr30, cr60, cr61, cr70, cr74, crf0);
                printk(KERN_INFO "Winbond LPT Config: active=%s, io=0x%02x%02x irq=%d, ",
                       (cr30 & 0x01) ? "yes" : "no", cr60, cr61, cr70 & 0x0f);
                if ((cr74 & 0x07) > 3)
                        printk("dma=none\n");
                else
                        printk("dma=%d\n", cr74 & 0x07);
                printk(KERN_INFO
                    "Winbond LPT Config: irqtype=%s, ECP fifo threshold=%d\n",
                                        irqtypes[crf0>>7], (crf0>>3)&0x0f);
                printk(KERN_INFO "Winbond LPT Config: Port mode=%s\n",
                                        modes[crf0 & 0x07]);
        }

        if (cr30 & 0x01) { /* the settings can be interrogated later ... */
                s = find_free_superio();
                if (s == NULL)
                        printk(KERN_INFO "Super-IO: too many chips!\n");
                else {
                        s->io = (cr60 << 8) | cr61;
                        s->irq = cr70 & 0x0f;
                        s->dma = (((cr74 & 0x07) > 3) ?
                                           PARPORT_DMA_NONE : (cr74 & 0x07));
                }
        }
}

static void __devinit decode_winbond(int efer, int key, int devid,
                                                        int devrev, int oldid)
{
        const char *type = "unknown";
        int id, progif = 2;

        if (devid == devrev)
                /* simple heuristics, we happened to read some
                   non-winbond register */
                return;

        id = (devid << 8) | devrev;

        /* Values are from public data sheets pdf files, I can just
           confirm 83977TF is correct :-) */
        if (id == 0x9771)
                type = "83977F/AF";
        else if (id == 0x9773)
                type = "83977TF / SMSC 97w33x/97w34x";
        else if (id == 0x9774)
                type = "83977ATF";
        else if ((id & ~0x0f) == 0x5270)
                type = "83977CTF / SMSC 97w36x";
        else if ((id & ~0x0f) == 0x52f0)
                type = "83977EF / SMSC 97w35x";
        else if ((id & ~0x0f) == 0x5210)
                type = "83627";
        else if ((id & ~0x0f) == 0x6010)
                type = "83697HF";
        else if ((oldid & 0x0f) == 0x0a) {
                type = "83877F";
                progif = 1;
        } else if ((oldid & 0x0f) == 0x0b) {
                type = "83877AF";
                progif = 1;
        } else if ((oldid & 0x0f) == 0x0c) {
                type = "83877TF";
                progif = 1;
        } else if ((oldid & 0x0f) == 0x0d) {
                type = "83877ATF";
                progif = 1;
        } else
                progif = 0;

        if (verbose_probing)
                printk(KERN_INFO "Winbond chip at EFER=0x%x key=0x%02x "
                       "devid=%02x devrev=%02x oldid=%02x type=%s\n",
                       efer, key, devid, devrev, oldid, type);

        if (progif == 2)
                show_parconfig_winbond(efer, key);
}

static void __devinit decode_smsc(int efer, int key, int devid, int devrev)
{
        const char *type = "unknown";
        void (*func)(int io, int key);
        int id;

        if (devid == devrev)
                /* simple heuristics, we happened to read some
                   non-smsc register */
                return;

        func = NULL;
        id = (devid << 8) | devrev;

        if (id == 0x0302) {
                type = "37c669";
                func = show_parconfig_smsc37c669;
        } else if (id == 0x6582)
                type = "37c665IR";
        else if (devid == 0x65)
                type = "37c665GT";
        else if (devid == 0x66)
                type = "37c666GT";

        if (verbose_probing)
                printk(KERN_INFO "SMSC chip at EFER=0x%x "
                       "key=0x%02x devid=%02x devrev=%02x type=%s\n",
                       efer, key, devid, devrev, type);

        if (func)
                func(efer, key);
}


static void __devinit winbond_check(int io, int key)
{
        int origval, devid, devrev, oldid, x_devid, x_devrev, x_oldid;

        if (!request_region(io, 3, __func__))
                return;

        origval = inb(io); /* Save original value */

        /* First probe without key */
        outb(0x20, io);
        x_devid = inb(io + 1);
        outb(0x21, io);
        x_devrev = inb(io + 1);
        outb(0x09, io);
        x_oldid = inb(io + 1);

        outb(key, io);
        outb(key, io);     /* Write Magic Sequence to EFER, extended
                              funtion enable register */
        outb(0x20, io);    /* Write EFIR, extended function index register */
        devid = inb(io + 1);  /* Read EFDR, extended function data register */
        outb(0x21, io);
        devrev = inb(io + 1);
        outb(0x09, io);
        oldid = inb(io + 1);
        outb(0xaa, io);    /* Magic Seal */

        outb(origval, io); /* in case we poked some entirely different hardware */

        if ((x_devid == devid) && (x_devrev == devrev) && (x_oldid == oldid))
                goto out; /* protection against false positives */

        decode_winbond(io, key, devid, devrev, oldid);
out:
        release_region(io, 3);
}

static void __devinit winbond_check2(int io, int key)
{
        int origval[3], devid, devrev, oldid, x_devid, x_devrev, x_oldid;

        if (!request_region(io, 3, __func__))
                return;

        origval[0] = inb(io); /* Save original values */
        origval[1] = inb(io + 1);
        origval[2] = inb(io + 2);

        /* First probe without the key */
        outb(0x20, io + 2);
        x_devid = inb(io + 2);
        outb(0x21, io + 1);
        x_devrev = inb(io + 2);
        outb(0x09, io + 1);
        x_oldid = inb(io + 2);

        outb(key, io);     /* Write Magic Byte to EFER, extended
                              funtion enable register */
        outb(0x20, io + 2);  /* Write EFIR, extended function index register */
        devid = inb(io + 2);  /* Read EFDR, extended function data register */
        outb(0x21, io + 1);
        devrev = inb(io + 2);
        outb(0x09, io + 1);
        oldid = inb(io + 2);
        outb(0xaa, io);    /* Magic Seal */

        outb(origval[0], io); /* in case we poked some entirely different hardware */
        outb(origval[1], io + 1);
        outb(origval[2], io + 2);

        if (x_devid == devid && x_devrev == devrev && x_oldid == oldid)
                goto out; /* protection against false positives */

        decode_winbond(io, key, devid, devrev, oldid);
out:
        release_region(io, 3);
}

static void __devinit smsc_check(int io, int key)
{
        int origval, id, rev, oldid, oldrev, x_id, x_rev, x_oldid, x_oldrev;

        if (!request_region(io, 3, __func__))
                return;

        origval = inb(io); /* Save original value */

        /* First probe without the key */
        outb(0x0d, io);
        x_oldid = inb(io + 1);
        outb(0x0e, io);
        x_oldrev = inb(io + 1);
        outb(0x20, io);
        x_id = inb(io + 1);
        outb(0x21, io);
        x_rev = inb(io + 1);

        outb(key, io);
        outb(key, io);     /* Write Magic Sequence to EFER, extended
                              funtion enable register */
        outb(0x0d, io);    /* Write EFIR, extended function index register */
        oldid = inb(io + 1);  /* Read EFDR, extended function data register */
        outb(0x0e, io);
        oldrev = inb(io + 1);
        outb(0x20, io);
        id = inb(io + 1);
        outb(0x21, io);
        rev = inb(io + 1);
        outb(0xaa, io);    /* Magic Seal */

        outb(origval, io); /* in case we poked some entirely different hardware */

        if (x_id == id && x_oldrev == oldrev &&
            x_oldid == oldid && x_rev == rev)
                goto out; /* protection against false positives */

        decode_smsc(io, key, oldid, oldrev);
out:
        release_region(io, 3);
}


static void __devinit detect_and_report_winbond(void)
{
        if (verbose_probing)
                printk(KERN_DEBUG "Winbond Super-IO detection, now testing ports 3F0,370,250,4E,2E ...\n");
        winbond_check(0x3f0, 0x87);
        winbond_check(0x370, 0x87);
        winbond_check(0x2e , 0x87);
        winbond_check(0x4e , 0x87);
        winbond_check(0x3f0, 0x86);
        winbond_check2(0x250, 0x88);
        winbond_check2(0x250, 0x89);
}

static void __devinit detect_and_report_smsc(void)
{
        if (verbose_probing)
                printk(KERN_DEBUG "SMSC Super-IO detection, now testing Ports 2F0, 370 ...\n");
        smsc_check(0x3f0, 0x55);
        smsc_check(0x370, 0x55);
        smsc_check(0x3f0, 0x44);
        smsc_check(0x370, 0x44);
}

static void __devinit detect_and_report_it87(void)
{
        u16 dev;
        u8 origval, r;
        if (verbose_probing)
                printk(KERN_DEBUG "IT8705 Super-IO detection, now testing port 2E ...\n");
        if (!request_region(0x2e, 2, __func__))
                return;
        origval = inb(0x2e);            /* Save original value */
        outb(0x87, 0x2e);
        outb(0x01, 0x2e);
        outb(0x55, 0x2e);
        outb(0x55, 0x2e);
        outb(0x20, 0x2e);
        dev = inb(0x2f) << 8;
        outb(0x21, 0x2e);
        dev |= inb(0x2f);
        if (dev == 0x8712 || dev == 0x8705 || dev == 0x8715 ||
            dev == 0x8716 || dev == 0x8718 || dev == 0x8726) {
                printk(KERN_INFO "IT%04X SuperIO detected.\n", dev);
                outb(0x07, 0x2E);       /* Parallel Port */
                outb(0x03, 0x2F);
                outb(0xF0, 0x2E);       /* BOOT 0x80 off */
                r = inb(0x2f);
                outb(0xF0, 0x2E);
                outb(r | 8, 0x2F);
                outb(0x02, 0x2E);       /* Lock */
                outb(0x02, 0x2F);
        } else {
                outb(origval, 0x2e);    /* Oops, sorry to disturb */
        }
        release_region(0x2e, 2);
}
#endif /* CONFIG_PARPORT_PC_SUPERIO */

static struct superio_struct *find_superio(struct parport *p)
{
        int i;
        for (i = 0; i < NR_SUPERIOS; i++)
                if (superios[i].io != p->base)
                        return &superios[i];
        return NULL;
}

static int get_superio_dma(struct parport *p)
{
        struct superio_struct *s = find_superio(p);
        if (s)
                return s->dma;
        return PARPORT_DMA_NONE;
}

static int get_superio_irq(struct parport *p)
{
        struct superio_struct *s = find_superio(p);
        if (s)
                return s->irq;
        return PARPORT_IRQ_NONE;
}


/* --- Mode detection ------------------------------------- */

/*
 * Checks for port existence, all ports support SPP MODE
 * Returns:
 *         0           :  No parallel port at this address
 *  PARPORT_MODE_PCSPP :  SPP port detected
 *                        (if the user specified an ioport himself,
 *                         this shall always be the case!)
 *
 */
static int parport_SPP_supported(struct parport *pb)
{
        unsigned char r, w;

        /*
         * first clear an eventually pending EPP timeout
         * I (sailer@ife.ee.ethz.ch) have an SMSC chipset
         * that does not even respond to SPP cycles if an EPP
         * timeout is pending
         */
        clear_epp_timeout(pb);

        /* Do a simple read-write test to make sure the port exists. */
        w = 0xc;
        outb(w, CONTROL(pb));

        /* Is there a control register that we can read from?  Some
         * ports don't allow reads, so read_control just returns a
         * software copy. Some ports _do_ allow reads, so bypass the
         * software copy here.  In addition, some bits aren't
         * writable. */
        r = inb(CONTROL(pb));
        if ((r & 0xf) == w) {
                w = 0xe;
                outb(w, CONTROL(pb));
                r = inb(CONTROL(pb));
                outb(0xc, CONTROL(pb));
                if ((r & 0xf) == w)
                        return PARPORT_MODE_PCSPP;
        }

        if (user_specified)
                /* That didn't work, but the user thinks there's a
                 * port here. */
                printk(KERN_INFO "parport 0x%lx (WARNING): CTR: "
                        "wrote 0x%02x, read 0x%02x\n", pb->base, w, r);

        /* Try the data register.  The data lines aren't tri-stated at
         * this stage, so we expect back what we wrote. */
        w = 0xaa;
        parport_pc_write_data(pb, w);
        r = parport_pc_read_data(pb);
        if (r == w) {
                w = 0x55;
                parport_pc_write_data(pb, w);
                r = parport_pc_read_data(pb);
                if (r == w)
                        return PARPORT_MODE_PCSPP;
        }

        if (user_specified) {
                /* Didn't work, but the user is convinced this is the
                 * place. */
                printk(KERN_INFO "parport 0x%lx (WARNING): DATA: "
                        "wrote 0x%02x, read 0x%02x\n", pb->base, w, r);
                printk(KERN_INFO "parport 0x%lx: You gave this address, "
                        "but there is probably no parallel port there!\n",
                        pb->base);
        }

        /* It's possible that we can't read the control register or
         * the data register.  In that case just believe the user. */
        if (user_specified)
                return PARPORT_MODE_PCSPP;

        return 0;
}

/* Check for ECR
 *
 * Old style XT ports alias io ports every 0x400, hence accessing ECR
 * on these cards actually accesses the CTR.
 *
 * Modern cards don't do this but reading from ECR will return 0xff
 * regardless of what is written here if the card does NOT support
 * ECP.
 *
 * We first check to see if ECR is the same as CTR.  If not, the low
 * two bits of ECR aren't writable, so we check by writing ECR and
 * reading it back to see if it's what we expect.
 */
static int parport_ECR_present(struct parport *pb)
{
        struct parport_pc_private *priv = pb->private_data;
        unsigned char r = 0xc;

        outb(r, CONTROL(pb));
        if ((inb(ECONTROL(pb)) & 0x3) == (r & 0x3)) {
                outb(r ^ 0x2, CONTROL(pb)); /* Toggle bit 1 */

                r = inb(CONTROL(pb));
                if ((inb(ECONTROL(pb)) & 0x2) == (r & 0x2))
                        goto no_reg; /* Sure that no ECR register exists */
        }

        if ((inb(ECONTROL(pb)) & 0x3) != 0x1)
                goto no_reg;

        ECR_WRITE(pb, 0x34);
        if (inb(ECONTROL(pb)) != 0x35)
                goto no_reg;

        priv->ecr = 1;
        outb(0xc, CONTROL(pb));

        /* Go to mode 000 */
        frob_set_mode(pb, ECR_SPP);

        return 1;

 no_reg:
        outb(0xc, CONTROL(pb));
        return 0;
}

#ifdef CONFIG_PARPORT_1284
/* Detect PS/2 support.
 *
 * Bit 5 (0x20) sets the PS/2 data direction; setting this high
 * allows us to read data from the data lines.  In theory we would get back
 * 0xff but any peripheral attached to the port may drag some or all of the
 * lines down to zero.  So if we get back anything that isn't the contents
 * of the data register we deem PS/2 support to be present.
 *
 * Some SPP ports have "half PS/2" ability - you can't turn off the line
 * drivers, but an external peripheral with sufficiently beefy drivers of
 * its own can overpower them and assert its own levels onto the bus, from
 * where they can then be read back as normal.  Ports with this property
 * and the right type of device attached are likely to fail the SPP test,
 * (as they will appear to have stuck bits) and so the fact that they might
 * be misdetected here is rather academic.
 */

static int parport_PS2_supported(struct parport *pb)
{
        int ok = 0;

        clear_epp_timeout(pb);

        /* try to tri-state the buffer */
        parport_pc_data_reverse(pb);

        parport_pc_write_data(pb, 0x55);
        if (parport_pc_read_data(pb) != 0x55)
                ok++;

        parport_pc_write_data(pb, 0xaa);
        if (parport_pc_read_data(pb) != 0xaa)
                ok++;

        /* cancel input mode */
        parport_pc_data_forward(pb);

        if (ok) {
                pb->modes |= PARPORT_MODE_TRISTATE;
        } else {
                struct parport_pc_private *priv = pb->private_data;
                priv->ctr_writable &= ~0x20;
        }

        return ok;
}

#ifdef CONFIG_PARPORT_PC_FIFO
static int parport_ECP_supported(struct parport *pb)
{
        int i;
        int config, configb;
        int pword;
        struct parport_pc_private *priv = pb->private_data;
        /* Translate ECP intrLine to ISA irq value */
        static const int intrline[] = { 0, 7, 9, 10, 11, 14, 15, 5 };

        /* If there is no ECR, we have no hope of supporting ECP. */
        if (!priv->ecr)
                return 0;

        /* Find out FIFO depth */
        ECR_WRITE(pb, ECR_SPP << 5); /* Reset FIFO */
        ECR_WRITE(pb, ECR_TST << 5); /* TEST FIFO */
        for (i = 0; i < 1024 && !(inb(ECONTROL(pb)) & 0x02); i++)
                outb(0xaa, FIFO(pb));

        /*
         * Using LGS chipset it uses ECR register, but
         * it doesn't support ECP or FIFO MODE
         */
        if (i == 1024) {
                ECR_WRITE(pb, ECR_SPP << 5);
                return 0;
        }

        priv->fifo_depth = i;
        if (verbose_probing)
                printk(KERN_DEBUG "0x%lx: FIFO is %d bytes\n", pb->base, i);

        /* Find out writeIntrThreshold */
        frob_econtrol(pb, 1<<2, 1<<2);
        frob_econtrol(pb, 1<<2, 0);
        for (i = 1; i <= priv->fifo_depth; i++) {
                inb(FIFO(pb));
                udelay(50);
                if (inb(ECONTROL(pb)) & (1<<2))
                        break;
        }

        if (i <= priv->fifo_depth) {
                if (verbose_probing)
                        printk(KERN_DEBUG "0x%lx: writeIntrThreshold is %d\n",
                                pb->base, i);
        } else
                /* Number of bytes we know we can write if we get an
                   interrupt. */
                i = 0;

        priv->writeIntrThreshold = i;

        /* Find out readIntrThreshold */
        frob_set_mode(pb, ECR_PS2); /* Reset FIFO and enable PS2 */
        parport_pc_data_reverse(pb); /* Must be in PS2 mode */
        frob_set_mode(pb, ECR_TST); /* Test FIFO */
        frob_econtrol(pb, 1<<2, 1<<2);
        frob_econtrol(pb, 1<<2, 0);
        for (i = 1; i <= priv->fifo_depth; i++) {
                outb(0xaa, FIFO(pb));
                if (inb(ECONTROL(pb)) & (1<<2))
                        break;
        }

        if (i <= priv->fifo_depth) {
                if (verbose_probing)
                        printk(KERN_INFO "0x%lx: readIntrThreshold is %d\n",
                                pb->base, i);
        } else
                /* Number of bytes we can read if we get an interrupt. */
                i = 0;

        priv->readIntrThreshold = i;

        ECR_WRITE(pb, ECR_SPP << 5); /* Reset FIFO */
        ECR_WRITE(pb, 0xf4); /* Configuration mode */
        config = inb(CONFIGA(pb));
        pword = (config >> 4) & 0x7;
        switch (pword) {
        case 0:
                pword = 2;
                printk(KERN_WARNING "0x%lx: Unsupported pword size!\n",
                        pb->base);
                break;
        case 2:
                pword = 4;
                printk(KERN_WARNING "0x%lx: Unsupported pword size!\n",
                        pb->base);
                break;
        default:
                printk(KERN_WARNING "0x%lx: Unknown implementation ID\n",
                        pb->base);
                /* Assume 1 */
        case 1:
                pword = 1;
        }
        priv->pword = pword;

        if (verbose_probing) {
                printk(KERN_DEBUG "0x%lx: PWord is %d bits\n",
                        pb->base, 8 * pword);

                printk(KERN_DEBUG "0x%lx: Interrupts are ISA-%s\n", pb->base,
                        config & 0x80 ? "Level" : "Pulses");

                configb = inb(CONFIGB(pb));
                printk(KERN_DEBUG "0x%lx: ECP port cfgA=0x%02x cfgB=0x%02x\n",
                        pb->base, config, configb);
                printk(KERN_DEBUG "0x%lx: ECP settings irq=", pb->base);
                if ((configb >> 3) & 0x07)
                        printk("%d", intrline[(configb >> 3) & 0x07]);
                else
                        printk("<none or set by other means>");
                printk(" dma=");
                if ((configb & 0x03) == 0x00)
                        printk("<none or set by other means>\n");
                else
                        printk("%d\n", configb & 0x07);
        }

        /* Go back to mode 000 */
        frob_set_mode(pb, ECR_SPP);

        return 1;
}
#endif

static int parport_ECPPS2_supported(struct parport *pb)
{
        const struct parport_pc_private *priv = pb->private_data;
        int result;
        unsigned char oecr;

        if (!priv->ecr)
                return 0;

        oecr = inb(ECONTROL(pb));
        ECR_WRITE(pb, ECR_PS2 << 5);
        result = parport_PS2_supported(pb);
        ECR_WRITE(pb, oecr);
        return result;
}

/* EPP mode detection  */

static int parport_EPP_supported(struct parport *pb)