#define AUTOSENSE
  #define PSEUDO_DMA
  #define FOO
  #define UNSAFE  /* Not unsafe for PAS16 -- use it */
  #define PDEBUG 0
  
  /*
   * 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
   * 
   * and 
   *
   * NCR 5380 Family
   * SCSI Protocol Controller
   * Databook
   *
   * NCR Microelectronics
   * 1635 Aeroplaza Drive
   * Colorado Springs, CO 80916
   * 1+ (719) 578-3400
   * 1+ (800) 334-5454
   */
  
  /*
   * Options : 
   * AUTOSENSE - if defined, REQUEST SENSE will be performed automatically
   *      for commands that return with a CHECK CONDITION status. 
   *
   * LIMIT_TRANSFERSIZE - if defined, limit the pseudo-dma transfers to 512
   *      bytes at a time.  Since interrupts are disabled by default during
   *      these transfers, we might need this to give reasonable interrupt
   *      service time if the transfer size gets too large.
   *
   * PSEUDO_DMA - enables PSEUDO-DMA hardware, should give a 3-4X performance
   * increase compared to polled I/O.
   *
   * PARITY - enable parity checking.  Not supported.
   * 
   * SCSI2 - enable support for SCSI-II tagged queueing.  Untested.
   *
   * UNSAFE - leave interrupts enabled during pseudo-DMA transfers.  This
   *	    parameter comes from the NCR5380 code.  It is NOT unsafe with
   *	    the PAS16 and you should use it.  If you don't you will have
   *	    a problem with dropped characters during high speed
   *	    communications during SCSI transfers.  If you really don't
   *	    want to use UNSAFE you can try defining LIMIT_TRANSFERSIZE or
   *	    twiddle with the transfer size in the high level code.
   *
   * USLEEP - enable support for devices that don't disconnect.  Untested.
   *
   * 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=0x388,255
   *
   *   SCSI_IRQ_NONE (255) should be specified for no interrupt,
   *   IRQ_AUTO (254) to autoprobe for an IRQ line if overridden
   *   on the command line.
   *
   *   (IRQ_AUTO == 254, SCSI_IRQ_NONE == 255 in NCR5380.h)
   */
   
  #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.h"
  #include <scsi/scsi_host.h>
  #include "pas16.h"
  #define AUTOPROBE_IRQ
  #include "NCR5380.h"
  
  
  static int pas_maxi = 0;
  static int pas_wmaxi = 0;
  static unsigned short pas16_addr = 0;
  static int pas16_irq = 0;
   
  
  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
  		    */
      };
  /*----------------------------------------------------------------*/
  /* the following will set the monitor border color (useful to find
   where something crashed or gets stuck at */
  /* 1 = blue
   2 = green
   3 = cyan
   4 = red
   5 = magenta
   6 = yellow
   7 = white
  */
  #if 1
  #define rtrc(i) {inb(0x3da); outb(0x31, 0x3c0); outb((i), 0x3c0);}
  #else
  #define rtrc(i) {}
  #endif
  
  
  /*
   * 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 */
  
  	NCR5380_read( 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
  " );
  	    /* 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 */
      NCR5380_write( MODE_REG, 0x20 );		/* Is it really SCSI? */
      if( NCR5380_read( MODE_REG ) != 0x20 )	/* Write to a reg.    */
  	return 0;				/* and try to read    */
      NCR5380_write( MODE_REG, 0x00 );		/* it back.	      */
      if( NCR5380_read( MODE_REG ) != 0x00 )
  	return 0;
  
      return 1;
  }
  
  
  /*
   * 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.
   *
   */
  
  void __init pas16_setup(char *str, int *ints)
  {
      static int commandline_current = 0;
      int i;
      if (ints[0] != 2) 
  	printk("pas16_setup : usage pas16=io_port,irq
  ");
      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;
  	}
  }
  
  /* 
   * 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.
   *
   */
  
  int __init pas16_detect(struct scsi_host_template * tpnt)
  {
      static int current_override = 0;
      static unsigned short current_base = 0;
      struct Scsi_Host *instance;
      unsigned short io_port;
      int  count;
  
      tpnt->proc_name = "pas16";
      tpnt->show_info = pas16_show_info;
      tpnt->write_info = pas16_write_info;
  
      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) {
  #if (PDEBUG & PDEBUG_INIT)
      printk("scsi-pas16 : probing io_port %04x
  ", (unsigned int) bases[current_base].io_port);
  #endif
  		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 ); 
  #if (PDEBUG & PDEBUG_INIT)
  			printk("scsi-pas16 : detected board.
  ");
  #endif
  		}
      }
  
  
  #if defined(PDEBUG) && (PDEBUG & PDEBUG_INIT)
  	printk("scsi-pas16 : io_port = %04x
  ", (unsigned int) io_port);
  #endif
  
  	if (!io_port)
  	    break;
  
  	instance = scsi_register (tpnt, sizeof(struct NCR5380_hostdata));
  	if(instance == NULL)
  		break;
  		
  	instance->io_port = io_port;
  
  	NCR5380_init(instance, 0);
  
  	if (overrides[current_override].irq != IRQ_AUTO)
  	    instance->irq = overrides[current_override].irq;
  	else 
  	    instance->irq = NCR5380_probe_irq(instance, PAS16_IRQS);
  
  	if (instance->irq != SCSI_IRQ_NONE) 
  	    if (request_irq(instance->irq, pas16_intr, IRQF_DISABLED,
  			    "pas16", instance)) {
  		printk("scsi%d : IRQ%d not free, interrupts disabled
  ", 
  		    instance->host_no, instance->irq);
  		instance->irq = SCSI_IRQ_NONE;
  	    } 
  
  	if (instance->irq == SCSI_IRQ_NONE) {
  	    printk("scsi%d : interrupts not enabled. for better interactive performance,
  ", instance->host_no);
  	    printk("scsi%d : please jumper the board for a free IRQ.
  ", 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 );
  	}
  
  #if defined(PDEBUG) && (PDEBUG & PDEBUG_INIT)
  	printk("scsi%d : irq = %d
  ", instance->host_no, instance->irq);
  #endif
  
  	printk("scsi%d : at 0x%04x", instance->host_no, (int) 
  	    instance->io_port);
  	if (instance->irq == SCSI_IRQ_NONE)
  	    printk (" interrupts disabled");
  	else 
  	    printk (" irq %d", instance->irq);
  	printk(" options CAN_QUEUE=%d  CMD_PER_LUN=%d release=%d",
  	    CAN_QUEUE, CMD_PER_LUN, PAS16_PUBLIC_RELEASE);
  	NCR5380_print_options(instance);
  	printk("
  ");
  
  	++current_override;
  	++count;
      }
      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.
   */
  
  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;
  
      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()
  ",
  	    instance->host_no);
  	return -1;
      }
     if (ii > pas_maxi)
        pas_maxi = 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;
  
      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()
  ",
  	    instance->host_no);
  	return -1;
      }
      if (ii > pas_maxi)
  	 pas_wmaxi = ii;
      return 0;
  }
  
  #include "NCR5380.c"
  
  static int pas16_release(struct Scsi_Host *shost)
  {
  	if (shost->irq)
  		free_irq(shost->irq, shost);
  	NCR5380_exit(shost);
  	if (shost->dma_channel != 0xff)
  		free_dma(shost->dma_channel);
  	if (shost->io_port && shost->n_io_port)
  		release_region(shost->io_port, shost->n_io_port);
  	scsi_unregister(shost);
  	return 0;
  }
  
  static struct scsi_host_template driver_template = {
  	.name           = "Pro Audio Spectrum-16 SCSI",
  	.detect         = pas16_detect,
  	.release        = pas16_release,
  	.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");