#define PSEUDO_DMA

/*
 * This driver adapted from Drew Eckhardt's Trantor T128 driver
 *
 * Copyright 1993, Drew Eckhardt
 *	Visionary Computing
 *	(Unix and Linux consulting and custom programming)
 *	drew@colorado.edu
 *      +1 (303) 666-5836
 *
 *  ( Based on T128 - DISTRIBUTION RELEASE 3. ) 
 *
 * Modified to work with the Pro Audio Spectrum/Studio 16
 * by John Weidman.
 *
 *
 * For more information, please consult 
 *
 * Media Vision
 * (510) 770-8600
 * (800) 348-7116
 */

/*
 * The card is detected and initialized in one of several ways : 
 * 1.  Autoprobe (default) - There are many different models of
 *     the Pro Audio Spectrum/Studio 16, and I only have one of
 *     them, so this may require a little tweaking.  An interrupt
 *     is triggered to autoprobe for the interrupt line.  Note:
 *     with the newer model boards, the interrupt is set via
 *     software after reset using the default_irq for the
 *     current board number.
 *
 * 2.  With command line overrides - pas16=port,irq may be 
 *     used on the LILO command line to override the defaults.
 *
 * 3.  With the PAS16_OVERRIDE compile time define.  This is 
 *     specified as an array of address, irq tuples.  Ie, for
 *     one board at the default 0x388 address, IRQ10, I could say 
 *     -DPAS16_OVERRIDE={{0x388, 10}}
 *     NOTE:  Untested.
 *	
 * 4.  When included as a module, with arguments passed on the command line:
 *         pas16_irq=xx		the interrupt
 *         pas16_addr=xx	the port
 *     e.g. "modprobe pas16 pas16_addr=0x388 pas16_irq=5"
 *
 *     Note that if the override methods are used, place holders must
 *     be specified for other boards in the system.
 *
 *
 * Configuration notes :
 *   The current driver does not support interrupt sharing with the
 *   sound portion of the card.  If you use the same irq for the
 *   scsi port and sound you will have problems.  Either use
 *   a different irq for the scsi port or don't use interrupts
 *   for the scsi port.
 *
 *   If you have problems with your card not being recognized, use
 *   the LILO command line override.  Try to get it recognized without
 *   interrupts.  Ie, for a board at the default 0x388 base port,
 *   boot: linux pas16=0x388,0
 *
 *   NO_IRQ (0) should be specified for no interrupt,
 *   IRQ_AUTO (254) to autoprobe for an IRQ line if overridden
 *   on the command line.
 */
 
#include <linux/module.h>

#include <linux/signal.h>
#include <linux/proc_fs.h>
#include <asm/io.h>
#include <asm/dma.h>
#include <linux/blkdev.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/stat.h>
#include <linux/init.h>

#include <scsi/scsi_host.h>
#include "pas16.h"
#define AUTOPROBE_IRQ
#include "NCR5380.h"


static unsigned short pas16_addr;
static int pas16_irq;
 

static const int scsi_irq_translate[] =
	{ 0,  0,  1,  2,  3,  4,  5,  6, 0,  0,  7,  8,  9,  0, 10, 11 };

/* The default_irqs array contains values used to set the irq into the
 * board via software (as must be done on newer model boards without
 * irq jumpers on the board).  The first value in the array will be
 * assigned to logical board 0, the next to board 1, etc.
 */
static int default_irqs[] __initdata =
	{  PAS16_DEFAULT_BOARD_1_IRQ,
	   PAS16_DEFAULT_BOARD_2_IRQ,
	   PAS16_DEFAULT_BOARD_3_IRQ,
	   PAS16_DEFAULT_BOARD_4_IRQ
	};

static struct override {
    unsigned short io_port;
    int  irq;
} overrides
#ifdef PAS16_OVERRIDE
    [] __initdata = PAS16_OVERRIDE;
#else
    [4] __initdata = {{0,IRQ_AUTO}, {0,IRQ_AUTO}, {0,IRQ_AUTO},
	{0,IRQ_AUTO}};
#endif

#define NO_OVERRIDES ARRAY_SIZE(overrides)

static struct base {
    unsigned short io_port;
    int noauto;
} bases[] __initdata =
	{ {PAS16_DEFAULT_BASE_1, 0},
	  {PAS16_DEFAULT_BASE_2, 0},
	  {PAS16_DEFAULT_BASE_3, 0},
	  {PAS16_DEFAULT_BASE_4, 0}
	};

#define NO_BASES ARRAY_SIZE(bases)

static const unsigned short  pas16_offset[ 8 ] =
    {
	0x1c00,    /* OUTPUT_DATA_REG */
	0x1c01,    /* INITIATOR_COMMAND_REG */
	0x1c02,    /* MODE_REG */
	0x1c03,    /* TARGET_COMMAND_REG */
	0x3c00,    /* STATUS_REG ro, SELECT_ENABLE_REG wo */
	0x3c01,    /* BUS_AND_STATUS_REG ro, START_DMA_SEND_REG wo */
	0x3c02,    /* INPUT_DATA_REGISTER ro, (N/A on PAS16 ?)
		    * START_DMA_TARGET_RECEIVE_REG wo
		    */
	0x3c03,    /* RESET_PARITY_INTERRUPT_REG ro,
		    * START_DMA_INITIATOR_RECEIVE_REG wo
		    */
    };


/*
 * Function : enable_board( int  board_num, unsigned short port )
 *
 * Purpose :  set address in new model board
 *
 * Inputs : board_num - logical board number 0-3, port - base address
 *
 */

static void __init
	enable_board( int  board_num,  unsigned short port )
{
    outb( 0xbc + board_num, MASTER_ADDRESS_PTR );
    outb( port >> 2, MASTER_ADDRESS_PTR );
}


/*
 * Function : init_board( unsigned short port, int irq )
 *
 * Purpose :  Set the board up to handle the SCSI interface
 *
 * Inputs : port - base address of the board,
 *	    irq - irq to assign to the SCSI port
 *	    force_irq - set it even if it conflicts with sound driver
 *
 */

static void __init 
	init_board( unsigned short io_port, int irq, int force_irq )
{
	unsigned int	tmp;
	unsigned int	pas_irq_code;

	/* Initialize the SCSI part of the board */

	outb( 0x30, io_port + P_TIMEOUT_COUNTER_REG );  /* Timeout counter */
	outb( 0x01, io_port + P_TIMEOUT_STATUS_REG_OFFSET );   /* Reset TC */
	outb( 0x01, io_port + WAIT_STATE );   /* 1 Wait state */

	inb(io_port + pas16_offset[RESET_PARITY_INTERRUPT_REG]);

	/* Set the SCSI interrupt pointer without mucking up the sound
	 * interrupt pointer in the same byte.
	 */
	pas_irq_code = ( irq < 16 ) ? scsi_irq_translate[irq] : 0;
	tmp = inb( io_port + IO_CONFIG_3 );

	if( (( tmp & 0x0f ) == pas_irq_code) && pas_irq_code > 0 
	    && !force_irq )
	{
	    printk( "pas16: WARNING: Can't use same irq as sound "
		    "driver -- interrupts disabled\n" );
	    /* Set up the drive parameters, disable 5380 interrupts */
	    outb( 0x4d, io_port + SYS_CONFIG_4 );
	}
	else
	{
	    tmp = (  tmp & 0x0f ) | ( pas_irq_code << 4 );
	    outb( tmp, io_port + IO_CONFIG_3 );

	    /* Set up the drive parameters and enable 5380 interrupts */
	    outb( 0x6d, io_port + SYS_CONFIG_4 );
	}
}


/*
 * Function : pas16_hw_detect( unsigned short board_num )
 *
 * Purpose : determine if a pas16 board is present
 * 
 * Inputs : board_num - logical board number ( 0 - 3 )
 *
 * Returns : 0 if board not found, 1 if found.
 */

static int __init 
     pas16_hw_detect( unsigned short  board_num )
{
    unsigned char	board_rev, tmp;
    unsigned short	io_port = bases[ board_num ].io_port;

    /* See if we can find a PAS16 board at the address associated
     * with this logical board number.
     */

    /* First, attempt to take a newer model board out of reset and
     * give it a base address.  This shouldn't affect older boards.
     */
    enable_board( board_num, io_port );

    /* Now see if it looks like a PAS16 board */
    board_rev = inb( io_port + PCB_CONFIG );

    if( board_rev == 0xff )
	return 0;

    tmp = board_rev ^ 0xe0;

    outb( tmp, io_port + PCB_CONFIG );
    tmp = inb( io_port + PCB_CONFIG );
    outb( board_rev, io_port + PCB_CONFIG );

    if( board_rev != tmp ) 	/* Not a PAS-16 */
	return 0;

    if( ( inb( io_port + OPERATION_MODE_1 ) & 0x03 ) != 0x03 ) 
	return 0;  	/* return if no SCSI interface found */

    /* Mediavision has some new model boards that return ID bits
     * that indicate a SCSI interface, but they're not (LMS).  We'll
     * put in an additional test to try to weed them out.
     */

	outb(0x01, io_port + WAIT_STATE);             /* 1 Wait state */
	outb(0x20, io_port + pas16_offset[MODE_REG]); /* Is it really SCSI? */
	if (inb(io_port + pas16_offset[MODE_REG]) != 0x20) /* Write to a reg. */
		return 0;                                  /* and try to read */
	outb(0x00, io_port + pas16_offset[MODE_REG]);      /* it back. */
	if (inb(io_port + pas16_offset[MODE_REG]) != 0x00)
		return 0;

    return 1;
}


#ifndef MODULE
/*
 * Function : pas16_setup(char *str, int *ints)
 *
 * Purpose : LILO command line initialization of the overrides array,
 * 
 * Inputs : str - unused, ints - array of integer parameters with ints[0]
 *	equal to the number of ints.
 *
 */

static int __init pas16_setup(char *str)
{
	static int commandline_current;
    int i;
    int ints[10];

    get_options(str, ARRAY_SIZE(ints), ints);
    if (ints[0] != 2) 
	printk("pas16_setup : usage pas16=io_port,irq\n");
    else 
	if (commandline_current < NO_OVERRIDES) {
	    overrides[commandline_current].io_port = (unsigned short) ints[1];
	    overrides[commandline_current].irq = ints[2];
	    for (i = 0; i < NO_BASES; ++i)
		if (bases[i].io_port == (unsigned short) ints[1]) {
 		    bases[i].noauto = 1;
		    break;
		}
	    ++commandline_current;
	}
    return 1;
}

__setup("pas16=", pas16_setup);
#endif

/* 
 * Function : int pas16_detect(struct scsi_host_template * tpnt)
 *
 * Purpose : detects and initializes PAS16 controllers
 *	that were autoprobed, overridden on the LILO command line, 
 *	or specified at compile time.
 *
 * Inputs : tpnt - template for this SCSI adapter.
 * 
 * Returns : 1 if a host adapter was found, 0 if not.
 *
 */

static int __init pas16_detect(struct scsi_host_template *tpnt)
{
	static int current_override;
	static unsigned short current_base;
    struct Scsi_Host *instance;
    unsigned short io_port;
    int  count;

    if (pas16_addr != 0) {
	overrides[0].io_port = pas16_addr;
	/*
	*  This is how we avoid seeing more than
	*  one host adapter at the same I/O port.
	*  Cribbed shamelessly from pas16_setup().
	*/
	for (count = 0; count < NO_BASES; ++count)
	    if (bases[count].io_port == pas16_addr) {
 		    bases[count].noauto = 1;
		    break;
	}
    }
    if (pas16_irq != 0)
	overrides[0].irq = pas16_irq;

    for (count = 0; current_override < NO_OVERRIDES; ++current_override) {
	io_port = 0;

	if (overrides[current_override].io_port)
	{
	    io_port = overrides[current_override].io_port;
	    enable_board( current_override, io_port );
	    init_board( io_port, overrides[current_override].irq, 1 );
	}
	else
	    for (; !io_port && (current_base < NO_BASES); ++current_base) {
		dprintk(NDEBUG_INIT, "pas16: probing io_port 0x%04x\n",
		        (unsigned int)bases[current_base].io_port);
		if ( !bases[current_base].noauto &&
		     pas16_hw_detect( current_base ) ){
			io_port = bases[current_base].io_port;
			init_board( io_port, default_irqs[ current_base ], 0 ); 
			dprintk(NDEBUG_INIT, "pas16: detected board\n");
		}
    }

	dprintk(NDEBUG_INIT, "pas16: io_port = 0x%04x\n",
	        (unsigned int)io_port);

	if (!io_port)
	    break;

	instance = scsi_register (tpnt, sizeof(struct NCR5380_hostdata));
	if(instance == NULL)
		goto out;
		
	instance->io_port = io_port;

	if (NCR5380_init(instance, 0))
		goto out_unregister;

	NCR5380_maybe_reset_bus(instance);

	if (overrides[current_override].irq != IRQ_AUTO)
	    instance->irq = overrides[current_override].irq;
	else 
	    instance->irq = NCR5380_probe_irq(instance, PAS16_IRQS);

	/* Compatibility with documented NCR5380 kernel parameters */
	if (instance->irq == 255)
		instance->irq = NO_IRQ;

	if (instance->irq != NO_IRQ)
	    if (request_irq(instance->irq, pas16_intr, 0,
			    "pas16", instance)) {
		printk("scsi%d : IRQ%d not free, interrupts disabled\n", 
		    instance->host_no, instance->irq);
		instance->irq = NO_IRQ;
	    } 

	if (instance->irq == NO_IRQ) {
	    printk("scsi%d : interrupts not enabled. for better interactive performance,\n", instance->host_no);
	    printk("scsi%d : please jumper the board for a free IRQ.\n", instance->host_no);
	    /* Disable 5380 interrupts, leave drive params the same */
	    outb( 0x4d, io_port + SYS_CONFIG_4 );
	    outb( (inb(io_port + IO_CONFIG_3) & 0x0f), io_port + IO_CONFIG_3 );
	}

	dprintk(NDEBUG_INIT, "scsi%d : irq = %d\n",
	        instance->host_no, instance->irq);

	++current_override;
	++count;
    }
    return count;

out_unregister:
	scsi_unregister(instance);
out:
	return count;
}

/*
 * Function : int pas16_biosparam(Disk *disk, struct block_device *dev, int *ip)
 *
 * Purpose : Generates a BIOS / DOS compatible H-C-S mapping for 
 *	the specified device / size.
 * 
 * Inputs : size = size of device in sectors (512 bytes), dev = block device
 *	major / minor, ip[] = {heads, sectors, cylinders}  
 *
 * Returns : always 0 (success), initializes ip
 *	
 */

/* 
 * XXX Most SCSI boards use this mapping, I could be incorrect.  Some one
 * using hard disks on a trantor should verify that this mapping corresponds
 * to that used by the BIOS / ASPI driver by running the linux fdisk program
 * and matching the H_C_S coordinates to what DOS uses.
 */

static int pas16_biosparam(struct scsi_device *sdev, struct block_device *dev,
                           sector_t capacity, int *ip)
{
  int size = capacity;
  ip[0] = 64;
  ip[1] = 32;
  ip[2] = size >> 11;		/* I think I have it as /(32*64) */
  if( ip[2] > 1024 ) {		/* yes, >, not >= */
	ip[0]=255;
	ip[1]=63;
	ip[2]=size/(63*255);
	if( ip[2] > 1023 )	/* yes >1023... */
		ip[2] = 1023;
  }

  return 0;
}

/*
 * Function : int NCR5380_pread (struct Scsi_Host *instance, 
 *	unsigned char *dst, int len)
 *
 * Purpose : Fast 5380 pseudo-dma read function, transfers len bytes to 
 *	dst
 * 
 * Inputs : dst = destination, len = length in bytes
 *
 * Returns : 0 on success, non zero on a failure such as a watchdog 
 * 	timeout.
 */

static inline int NCR5380_pread (struct Scsi_Host *instance, unsigned char *dst,
    int len) {
    register unsigned char  *d = dst;
    register unsigned short reg = (unsigned short) (instance->io_port + 
	P_DATA_REG_OFFSET);
    register int i = len;
    int ii = 0;
    struct NCR5380_hostdata *hostdata = shost_priv(instance);

    while ( !(inb(instance->io_port + P_STATUS_REG_OFFSET) & P_ST_RDY) )
	 ++ii;

    insb( reg, d, i );

    if ( inb(instance->io_port + P_TIMEOUT_STATUS_REG_OFFSET) & P_TS_TIM) {
	outb( P_TS_CT, instance->io_port + P_TIMEOUT_STATUS_REG_OFFSET);
	printk("scsi%d : watchdog timer fired in NCR5380_pread()\n",
	    instance->host_no);
	return -1;
    }
    if (ii > hostdata->spin_max_r)
        hostdata->spin_max_r = ii;
    return 0;
}

/*
 * Function : int NCR5380_pwrite (struct Scsi_Host *instance, 
 *	unsigned char *src, int len)
 *
 * Purpose : Fast 5380 pseudo-dma write function, transfers len bytes from
 *	src
 * 
 * Inputs : src = source, len = length in bytes
 *
 * Returns : 0 on success, non zero on a failure such as a watchdog 
 * 	timeout.
 */

static inline int NCR5380_pwrite (struct Scsi_Host *instance, unsigned char *src,
    int len) {
    register unsigned char *s = src;
    register unsigned short reg = (instance->io_port + P_DATA_REG_OFFSET);
    register int i = len;
    int ii = 0;
    struct NCR5380_hostdata *hostdata = shost_priv(instance);

    while ( !((inb(instance->io_port + P_STATUS_REG_OFFSET)) & P_ST_RDY) )
	 ++ii;
 
    outsb( reg, s, i );

    if (inb(instance->io_port + P_TIMEOUT_STATUS_REG_OFFSET) & P_TS_TIM) {
	outb( P_TS_CT, instance->io_port + P_TIMEOUT_STATUS_REG_OFFSET);
	printk("scsi%d : watchdog timer fired in NCR5380_pwrite()\n",
	    instance->host_no);
	return -1;
    }
    if (ii > hostdata->spin_max_w)
        hostdata->spin_max_w = ii;
    return 0;
}

#include "NCR5380.c"

static int pas16_release(struct Scsi_Host *shost)
{
	if (shost->irq != NO_IRQ)
		free_irq(shost->irq, shost);
	NCR5380_exit(shost);
	scsi_unregister(shost);
	return 0;
}

static struct scsi_host_template driver_template = {
	.name           = "Pro Audio Spectrum-16 SCSI",
	.detect         = pas16_detect,
	.release        = pas16_release,
	.proc_name      = "pas16",
	.show_info      = pas16_show_info,
	.write_info     = pas16_write_info,
	.info           = pas16_info,
	.queuecommand   = pas16_queue_command,
	.eh_abort_handler = pas16_abort,
	.eh_bus_reset_handler = pas16_bus_reset,
	.bios_param     = pas16_biosparam, 
	.can_queue      = CAN_QUEUE,
	.this_id        = 7,
	.sg_tablesize   = SG_ALL,
	.cmd_per_lun    = CMD_PER_LUN,
	.use_clustering = DISABLE_CLUSTERING,
};
#include "scsi_module.c"

#ifdef MODULE
module_param(pas16_addr, ushort, 0);
module_param(pas16_irq, int, 0);
#endif
MODULE_LICENSE("GPL");