/*
  comedi/drivers/s626.c
  Sensoray s626 Comedi driver

  COMEDI - Linux Control and Measurement Device Interface
  Copyright (C) 2000 David A. Schleef <ds@schleef.org>

  Based on Sensoray Model 626 Linux driver Version 0.2
  Copyright (C) 2002-2004 Sensoray Co., Inc.

  This program is free software; you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
  the Free Software Foundation; either version 2 of the License, or
  (at your option) any later version.

  This program is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with this program; if not, write to the Free Software
  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

*/

/*
Driver: s626
Description: Sensoray 626 driver
Devices: [Sensoray] 626 (s626)
Authors: Gianluca Palli <gpalli@deis.unibo.it>,
Updated: Fri, 15 Feb 2008 10:28:42 +0000
Status: experimental

Configuration options:
  [0] - PCI bus of device (optional)
  [1] - PCI slot of device (optional)
  If bus/slot is not specified, the first supported
  PCI device found will be used.

INSN_CONFIG instructions:
  analog input:
   none

  analog output:
   none

  digital channel:
   s626 has 3 dio subdevices (2,3 and 4) each with 16 i/o channels
   supported configuration options:
   INSN_CONFIG_DIO_QUERY
   COMEDI_INPUT
   COMEDI_OUTPUT

  encoder:
   Every channel must be configured before reading.

   Example code

   insn.insn=INSN_CONFIG;   //configuration instruction
   insn.n=1;                //number of operation (must be 1)
   insn.data=&initialvalue; //initial value loaded into encoder
                            //during configuration
   insn.subdev=5;           //encoder subdevice
   insn.chanspec=CR_PACK(encoder_channel,0,AREF_OTHER); //encoder_channel
                                                        //to configure

   comedi_do_insn(cf,&insn); //executing configuration
*/

#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/types.h>

#include "../comedidev.h"

#include "comedi_pci.h"

#include "comedi_fc.h"
#include "s626.h"

MODULE_AUTHOR("Gianluca Palli <gpalli@deis.unibo.it>");
MODULE_DESCRIPTION("Sensoray 626 Comedi driver module");
MODULE_LICENSE("GPL");

struct s626_board {
        const char *name;
        int ai_chans;
        int ai_bits;
        int ao_chans;
        int ao_bits;
        int dio_chans;
        int dio_banks;
        int enc_chans;
};

static const struct s626_board s626_boards[] = {
        {
         .name = "s626",
         .ai_chans = S626_ADC_CHANNELS,
         .ai_bits = 14,
         .ao_chans = S626_DAC_CHANNELS,
         .ao_bits = 13,
         .dio_chans = S626_DIO_CHANNELS,
         .dio_banks = S626_DIO_BANKS,
         .enc_chans = S626_ENCODER_CHANNELS,
         }
};

#define thisboard ((const struct s626_board *)dev->board_ptr)
#define PCI_VENDOR_ID_S626 0x1131
#define PCI_DEVICE_ID_S626 0x7146

/*
 * For devices with vendor:device id == 0x1131:0x7146 you must specify
 * also subvendor:subdevice ids, because otherwise it will conflict with
 * Philips SAA7146 media/dvb based cards.
 */
static DEFINE_PCI_DEVICE_TABLE(s626_pci_table) = {
        {PCI_VENDOR_ID_S626, PCI_DEVICE_ID_S626, 0x6000, 0x0272, 0, 0, 0},
        {0}
};

MODULE_DEVICE_TABLE(pci, s626_pci_table);

static int s626_attach(struct comedi_device *dev, struct comedi_devconfig *it);
static int s626_detach(struct comedi_device *dev);

static struct comedi_driver driver_s626 = {
        .driver_name = "s626",
        .module = THIS_MODULE,
        .attach = s626_attach,
        .detach = s626_detach,
};

struct s626_private {
        struct pci_dev *pdev;
        void *base_addr;
        int got_regions;
        short allocatedBuf;
        uint8_t ai_cmd_running; /*  ai_cmd is running */
        uint8_t ai_continous;   /*  continous aquisition */
        int ai_sample_count;    /*  number of samples to aquire */
        unsigned int ai_sample_timer;
        /*  time between samples in  units of the timer */
        int ai_convert_count;   /*  conversion counter */
        unsigned int ai_convert_timer;
        /*  time between conversion in  units of the timer */
        uint16_t CounterIntEnabs;
        /* Counter interrupt enable  mask for MISC2 register. */
        uint8_t AdcItems;       /* Number of items in ADC poll  list. */
        struct bufferDMA RPSBuf;        /* DMA buffer used to hold ADC (RPS1) program. */
        struct bufferDMA ANABuf;
        /* DMA buffer used to receive ADC data and hold DAC data. */
        uint32_t *pDacWBuf;
        /* Pointer to logical adrs of DMA buffer used to hold DAC  data. */
        uint16_t Dacpol;        /* Image of DAC polarity register. */
        uint8_t TrimSetpoint[12];       /* Images of TrimDAC setpoints */
        uint16_t ChargeEnabled; /* Image of MISC2 Battery */
        /* Charge Enabled (0 or WRMISC2_CHARGE_ENABLE). */
        uint16_t WDInterval;    /* Image of MISC2 watchdog interval control bits. */
        uint32_t I2CAdrs;
        /* I2C device address for onboard EEPROM (board rev dependent). */
        /*   short         I2Cards; */
        unsigned int ao_readback[S626_DAC_CHANNELS];
};

struct dio_private {
        uint16_t RDDIn;
        uint16_t WRDOut;
        uint16_t RDEdgSel;
        uint16_t WREdgSel;
        uint16_t RDCapSel;
        uint16_t WRCapSel;
        uint16_t RDCapFlg;
        uint16_t RDIntSel;
        uint16_t WRIntSel;
};

static struct dio_private dio_private_A = {
        .RDDIn = LP_RDDINA,
        .WRDOut = LP_WRDOUTA,
        .RDEdgSel = LP_RDEDGSELA,
        .WREdgSel = LP_WREDGSELA,
        .RDCapSel = LP_RDCAPSELA,
        .WRCapSel = LP_WRCAPSELA,
        .RDCapFlg = LP_RDCAPFLGA,
        .RDIntSel = LP_RDINTSELA,
        .WRIntSel = LP_WRINTSELA,
};

static struct dio_private dio_private_B = {
        .RDDIn = LP_RDDINB,
        .WRDOut = LP_WRDOUTB,
        .RDEdgSel = LP_RDEDGSELB,
        .WREdgSel = LP_WREDGSELB,
        .RDCapSel = LP_RDCAPSELB,
        .WRCapSel = LP_WRCAPSELB,
        .RDCapFlg = LP_RDCAPFLGB,
        .RDIntSel = LP_RDINTSELB,
        .WRIntSel = LP_WRINTSELB,
};

static struct dio_private dio_private_C = {
        .RDDIn = LP_RDDINC,
        .WRDOut = LP_WRDOUTC,
        .RDEdgSel = LP_RDEDGSELC,
        .WREdgSel = LP_WREDGSELC,
        .RDCapSel = LP_RDCAPSELC,
        .WRCapSel = LP_WRCAPSELC,
        .RDCapFlg = LP_RDCAPFLGC,
        .RDIntSel = LP_RDINTSELC,
        .WRIntSel = LP_WRINTSELC,
};

/* to group dio devices (48 bits mask and data are not allowed ???)
static struct dio_private *dio_private_word[]={
  &dio_private_A,
  &dio_private_B,
  &dio_private_C,
};
*/

#define devpriv ((struct s626_private *)dev->private)
#define diopriv ((struct dio_private *)s->private)

COMEDI_PCI_INITCLEANUP_NOMODULE(driver_s626, s626_pci_table);

/* ioctl routines */
static int s626_ai_insn_config(struct comedi_device *dev,
                               struct comedi_subdevice *s,
                               struct comedi_insn *insn, unsigned int *data);
/* static int s626_ai_rinsn(struct comedi_device *dev,struct comedi_subdevice *s,struct comedi_insn *insn,unsigned int *data); */
static int s626_ai_insn_read(struct comedi_device *dev,
                             struct comedi_subdevice *s,
                             struct comedi_insn *insn, unsigned int *data);
static int s626_ai_cmd(struct comedi_device *dev, struct comedi_subdevice *s);
static int s626_ai_cmdtest(struct comedi_device *dev,
                           struct comedi_subdevice *s, struct comedi_cmd *cmd);
static int s626_ai_cancel(struct comedi_device *dev,
                          struct comedi_subdevice *s);
static int s626_ao_winsn(struct comedi_device *dev, struct comedi_subdevice *s,
                         struct comedi_insn *insn, unsigned int *data);
static int s626_ao_rinsn(struct comedi_device *dev, struct comedi_subdevice *s,
                         struct comedi_insn *insn, unsigned int *data);
static int s626_dio_insn_bits(struct comedi_device *dev,
                              struct comedi_subdevice *s,
                              struct comedi_insn *insn, unsigned int *data);
static int s626_dio_insn_config(struct comedi_device *dev,
                                struct comedi_subdevice *s,
                                struct comedi_insn *insn, unsigned int *data);
static int s626_dio_set_irq(struct comedi_device *dev, unsigned int chan);
static int s626_dio_reset_irq(struct comedi_device *dev, unsigned int gruop,
                              unsigned int mask);
static int s626_dio_clear_irq(struct comedi_device *dev);
static int s626_enc_insn_config(struct comedi_device *dev,
                                struct comedi_subdevice *s,
                                struct comedi_insn *insn, unsigned int *data);
static int s626_enc_insn_read(struct comedi_device *dev,
                              struct comedi_subdevice *s,
                              struct comedi_insn *insn, unsigned int *data);
static int s626_enc_insn_write(struct comedi_device *dev,
                               struct comedi_subdevice *s,
                               struct comedi_insn *insn, unsigned int *data);
static int s626_ns_to_timer(int *nanosec, int round_mode);
static int s626_ai_load_polllist(uint8_t * ppl, struct comedi_cmd *cmd);
static int s626_ai_inttrig(struct comedi_device *dev,
                           struct comedi_subdevice *s, unsigned int trignum);
static irqreturn_t s626_irq_handler(int irq, void *d);
static unsigned int s626_ai_reg_to_uint(int data);
/* static unsigned int s626_uint_to_reg(struct comedi_subdevice *s, int data); */

/* end ioctl routines */

/* internal routines */
static void s626_dio_init(struct comedi_device *dev);
static void ResetADC(struct comedi_device *dev, uint8_t * ppl);
static void LoadTrimDACs(struct comedi_device *dev);
static void WriteTrimDAC(struct comedi_device *dev, uint8_t LogicalChan,
                         uint8_t DacData);
static uint8_t I2Cread(struct comedi_device *dev, uint8_t addr);
static uint32_t I2Chandshake(struct comedi_device *dev, uint32_t val);
static void SetDAC(struct comedi_device *dev, uint16_t chan, short dacdata);
static void SendDAC(struct comedi_device *dev, uint32_t val);
static void WriteMISC2(struct comedi_device *dev, uint16_t NewImage);
static void DEBItransfer(struct comedi_device *dev);
static uint16_t DEBIread(struct comedi_device *dev, uint16_t addr);
static void DEBIwrite(struct comedi_device *dev, uint16_t addr, uint16_t wdata);
static void DEBIreplace(struct comedi_device *dev, uint16_t addr, uint16_t mask,
                        uint16_t wdata);
static void CloseDMAB(struct comedi_device *dev, struct bufferDMA *pdma,
                      size_t bsize);

/*  COUNTER OBJECT ------------------------------------------------ */
struct enc_private {
        /*  Pointers to functions that differ for A and B counters: */
        uint16_t(*GetEnable) (struct comedi_device * dev, struct enc_private *);        /* Return clock enable. */
        uint16_t(*GetIntSrc) (struct comedi_device * dev, struct enc_private *);        /* Return interrupt source. */
        uint16_t(*GetLoadTrig) (struct comedi_device * dev, struct enc_private *);      /* Return preload trigger source. */
        uint16_t(*GetMode) (struct comedi_device * dev, struct enc_private *);  /* Return standardized operating mode. */
        void (*PulseIndex) (struct comedi_device * dev, struct enc_private *);  /* Generate soft index strobe. */
        void (*SetEnable) (struct comedi_device * dev, struct enc_private *, uint16_t enab);    /* Program clock enable. */
        void (*SetIntSrc) (struct comedi_device * dev, struct enc_private *, uint16_t IntSource);       /* Program interrupt source. */
        void (*SetLoadTrig) (struct comedi_device * dev, struct enc_private *, uint16_t Trig);  /* Program preload trigger source. */
        void (*SetMode) (struct comedi_device * dev, struct enc_private *, uint16_t Setup, uint16_t DisableIntSrc);     /* Program standardized operating mode. */
        void (*ResetCapFlags) (struct comedi_device * dev, struct enc_private *);       /* Reset event capture flags. */

        uint16_t MyCRA;         /*    Address of CRA register. */
        uint16_t MyCRB;         /*    Address of CRB register. */
        uint16_t MyLatchLsw;    /*    Address of Latch least-significant-word */
        /*    register. */
        uint16_t MyEventBits[4];        /*    Bit translations for IntSrc -->RDMISC2. */
};

#define encpriv ((struct enc_private *)(dev->subdevices+5)->private)

/* counters routines */
static void s626_timer_load(struct comedi_device *dev, struct enc_private *k,
                            int tick);
static uint32_t ReadLatch(struct comedi_device *dev, struct enc_private *k);
static void ResetCapFlags_A(struct comedi_device *dev, struct enc_private *k);
static void ResetCapFlags_B(struct comedi_device *dev, struct enc_private *k);
static uint16_t GetMode_A(struct comedi_device *dev, struct enc_private *k);
static uint16_t GetMode_B(struct comedi_device *dev, struct enc_private *k);
static void SetMode_A(struct comedi_device *dev, struct enc_private *k,
                      uint16_t Setup, uint16_t DisableIntSrc);
static void SetMode_B(struct comedi_device *dev, struct enc_private *k,
                      uint16_t Setup, uint16_t DisableIntSrc);
static void SetEnable_A(struct comedi_device *dev, struct enc_private *k,
                        uint16_t enab);
static void SetEnable_B(struct comedi_device *dev, struct enc_private *k,
                        uint16_t enab);
static uint16_t GetEnable_A(struct comedi_device *dev, struct enc_private *k);
static uint16_t GetEnable_B(struct comedi_device *dev, struct enc_private *k);
static void SetLatchSource(struct comedi_device *dev, struct enc_private *k,
                           uint16_t value);
/* static uint16_t GetLatchSource(struct comedi_device *dev, struct enc_private *k ); */
static void SetLoadTrig_A(struct comedi_device *dev, struct enc_private *k,
                          uint16_t Trig);
static void SetLoadTrig_B(struct comedi_device *dev, struct enc_private *k,
                          uint16_t Trig);
static uint16_t GetLoadTrig_A(struct comedi_device *dev, struct enc_private *k);
static uint16_t GetLoadTrig_B(struct comedi_device *dev, struct enc_private *k);
static void SetIntSrc_B(struct comedi_device *dev, struct enc_private *k,
                        uint16_t IntSource);
static void SetIntSrc_A(struct comedi_device *dev, struct enc_private *k,
                        uint16_t IntSource);
static uint16_t GetIntSrc_A(struct comedi_device *dev, struct enc_private *k);
static uint16_t GetIntSrc_B(struct comedi_device *dev, struct enc_private *k);
/* static void SetClkMult(struct comedi_device *dev, struct enc_private *k, uint16_t value ) ; */
/* static uint16_t GetClkMult(struct comedi_device *dev, struct enc_private *k ) ; */
/* static void SetIndexPol(struct comedi_device *dev, struct enc_private *k, uint16_t value ); */
/* static uint16_t GetClkPol(struct comedi_device *dev, struct enc_private *k ) ; */
/* static void SetIndexSrc( struct comedi_device *dev,struct enc_private *k, uint16_t value );  */
/* static uint16_t GetClkSrc( struct comedi_device *dev,struct enc_private *k );  */
/* static void SetIndexSrc( struct comedi_device *dev,struct enc_private *k, uint16_t value );  */
/* static uint16_t GetIndexSrc( struct comedi_device *dev,struct enc_private *k );  */
static void PulseIndex_A(struct comedi_device *dev, struct enc_private *k);
static void PulseIndex_B(struct comedi_device *dev, struct enc_private *k);
static void Preload(struct comedi_device *dev, struct enc_private *k,
                    uint32_t value);
static void CountersInit(struct comedi_device *dev);
/* end internal routines */

/*  Counter objects constructor. */

/*  Counter overflow/index event flag masks for RDMISC2. */
#define INDXMASK(C)             (1 << (((C) > 2) ? ((C) * 2 - 1) : ((C) * 2 +  4)))
#define OVERMASK(C)             (1 << (((C) > 2) ? ((C) * 2 + 5) : ((C) * 2 + 10)))
#define EVBITS(C)               { 0, OVERMASK(C), INDXMASK(C), OVERMASK(C) | INDXMASK(C) }

/*  Translation table to map IntSrc into equivalent RDMISC2 event flag  bits. */
/* static const uint16_t EventBits[][4] = { EVBITS(0), EVBITS(1), EVBITS(2), EVBITS(3), EVBITS(4), EVBITS(5) }; */

/* struct enc_private; */
static struct enc_private enc_private_data[] = {
        {
         .GetEnable = GetEnable_A,
         .GetIntSrc = GetIntSrc_A,
         .GetLoadTrig = GetLoadTrig_A,
         .GetMode = GetMode_A,
         .PulseIndex = PulseIndex_A,
         .SetEnable = SetEnable_A,
         .SetIntSrc = SetIntSrc_A,
         .SetLoadTrig = SetLoadTrig_A,
         .SetMode = SetMode_A,
         .ResetCapFlags = ResetCapFlags_A,
         .MyCRA = LP_CR0A,
         .MyCRB = LP_CR0B,
         .MyLatchLsw = LP_CNTR0ALSW,
         .MyEventBits = EVBITS(0),
         },
        {
         .GetEnable = GetEnable_A,
         .GetIntSrc = GetIntSrc_A,
         .GetLoadTrig = GetLoadTrig_A,
         .GetMode = GetMode_A,
         .PulseIndex = PulseIndex_A,
         .SetEnable = SetEnable_A,
         .SetIntSrc = SetIntSrc_A,
         .SetLoadTrig = SetLoadTrig_A,
         .SetMode = SetMode_A,
         .ResetCapFlags = ResetCapFlags_A,
         .MyCRA = LP_CR1A,
         .MyCRB = LP_CR1B,
         .MyLatchLsw = LP_CNTR1ALSW,
         .MyEventBits = EVBITS(1),
         },
        {
         .GetEnable = GetEnable_A,
         .GetIntSrc = GetIntSrc_A,
         .GetLoadTrig = GetLoadTrig_A,
         .GetMode = GetMode_A,
         .PulseIndex = PulseIndex_A,
         .SetEnable = SetEnable_A,
         .SetIntSrc = SetIntSrc_A,
         .SetLoadTrig = SetLoadTrig_A,
         .SetMode = SetMode_A,
         .ResetCapFlags = ResetCapFlags_A,
         .MyCRA = LP_CR2A,
         .MyCRB = LP_CR2B,
         .MyLatchLsw = LP_CNTR2ALSW,
         .MyEventBits = EVBITS(2),
         },
        {
         .GetEnable = GetEnable_B,
         .GetIntSrc = GetIntSrc_B,
         .GetLoadTrig = GetLoadTrig_B,
         .GetMode = GetMode_B,
         .PulseIndex = PulseIndex_B,
         .SetEnable = SetEnable_B,
         .SetIntSrc = SetIntSrc_B,
         .SetLoadTrig = SetLoadTrig_B,
         .SetMode = SetMode_B,
         .ResetCapFlags = ResetCapFlags_B,
         .MyCRA = LP_CR0A,
         .MyCRB = LP_CR0B,
         .MyLatchLsw = LP_CNTR0BLSW,
         .MyEventBits = EVBITS(3),
         },
        {
         .GetEnable = GetEnable_B,
         .GetIntSrc = GetIntSrc_B,
         .GetLoadTrig = GetLoadTrig_B,
         .GetMode = GetMode_B,
         .PulseIndex = PulseIndex_B,
         .SetEnable = SetEnable_B,
         .SetIntSrc = SetIntSrc_B,
         .SetLoadTrig = SetLoadTrig_B,
         .SetMode = SetMode_B,
         .ResetCapFlags = ResetCapFlags_B,
         .MyCRA = LP_CR1A,
         .MyCRB = LP_CR1B,
         .MyLatchLsw = LP_CNTR1BLSW,
         .MyEventBits = EVBITS(4),
         },
        {
         .GetEnable = GetEnable_B,
         .GetIntSrc = GetIntSrc_B,
         .GetLoadTrig = GetLoadTrig_B,
         .GetMode = GetMode_B,
         .PulseIndex = PulseIndex_B,
         .SetEnable = SetEnable_B,
         .SetIntSrc = SetIntSrc_B,
         .SetLoadTrig = SetLoadTrig_B,
         .SetMode = SetMode_B,
         .ResetCapFlags = ResetCapFlags_B,
         .MyCRA = LP_CR2A,
         .MyCRB = LP_CR2B,
         .MyLatchLsw = LP_CNTR2BLSW,
         .MyEventBits = EVBITS(5),
         },
};

/*  enab/disable a function or test status bit(s) that are accessed */
/*  through Main Control Registers 1 or 2. */
#define MC_ENABLE(REGADRS, CTRLWORD)    writel(((uint32_t)(CTRLWORD) << 16) | (uint32_t)(CTRLWORD), devpriv->base_addr+(REGADRS))

#define MC_DISABLE(REGADRS, CTRLWORD)   writel((uint32_t)(CTRLWORD) << 16 , devpriv->base_addr+(REGADRS))

#define MC_TEST(REGADRS, CTRLWORD)      ((readl(devpriv->base_addr+(REGADRS)) & CTRLWORD) != 0)

/* #define WR7146(REGARDS,CTRLWORD)
    writel(CTRLWORD,(uint32_t)(devpriv->base_addr+(REGARDS))) */
#define WR7146(REGARDS, CTRLWORD) writel(CTRLWORD, devpriv->base_addr+(REGARDS))

/* #define RR7146(REGARDS)
    readl((uint32_t)(devpriv->base_addr+(REGARDS))) */
#define RR7146(REGARDS)         readl(devpriv->base_addr+(REGARDS))

#define BUGFIX_STREG(REGADRS)   (REGADRS - 4)

/*  Write a time slot control record to TSL2. */
#define VECTPORT(VECTNUM)               (P_TSL2 + ((VECTNUM) << 2))
#define SETVECT(VECTNUM, VECTVAL)       WR7146(VECTPORT(VECTNUM), (VECTVAL))

/*  Code macros used for constructing I2C command bytes. */
#define I2C_B2(ATTR, VAL)       (((ATTR) << 6) | ((VAL) << 24))
#define I2C_B1(ATTR, VAL)       (((ATTR) << 4) | ((VAL) << 16))
#define I2C_B0(ATTR, VAL)       (((ATTR) << 2) | ((VAL) <<  8))

static const struct comedi_lrange s626_range_table = { 2, {
                                                           RANGE(-5, 5),
                                                           RANGE(-10, 10),
                                                           }
};

static int s626_attach(struct comedi_device *dev, struct comedi_devconfig *it)
{
/*   uint8_t    PollList; */
/*   uint16_t   AdcData; */
/*   uint16_t   StartVal; */
/*   uint16_t   index; */
/*   unsigned int data[16]; */
        int result;
        int i;
        int ret;
        resource_size_t resourceStart;
        dma_addr_t appdma;
        struct comedi_subdevice *s;
        const struct pci_device_id *ids;
        struct pci_dev *pdev = NULL;

        if (alloc_private(dev, sizeof(struct s626_private)) < 0)
                return -ENOMEM;

        for (i = 0; i < (ARRAY_SIZE(s626_pci_table) - 1) && !pdev; i++) {
                ids = &s626_pci_table[i];
                do {
                        pdev = pci_get_subsys(ids->vendor, ids->device,
                                              ids->subvendor, ids->subdevice,
                                              pdev);

                        if ((it->options[0] || it->options[1]) && pdev) {
                                /* matches requested bus/slot */
                                if (pdev->bus->number == it->options[0] &&
                                    PCI_SLOT(pdev->devfn) == it->options[1])
                                        break;
                        } else
                                break;
                } while (1);
        }
        devpriv->pdev = pdev;

        if (pdev == NULL) {
                printk("s626_attach: Board not present!!!\n");
                return -ENODEV;
        }

        result = comedi_pci_enable(pdev, "s626");
        if (result < 0) {
                printk("s626_attach: comedi_pci_enable fails\n");
                return -ENODEV;
        }
        devpriv->got_regions = 1;

        resourceStart = pci_resource_start(devpriv->pdev, 0);

        devpriv->base_addr = ioremap(resourceStart, SIZEOF_ADDRESS_SPACE);
        if (devpriv->base_addr == NULL) {
                printk("s626_attach: IOREMAP failed\n");
                return -ENODEV;
        }

        if (devpriv->base_addr) {
                /* disable master interrupt */
                writel(0, devpriv->base_addr + P_IER);

                /* soft reset */
                writel(MC1_SOFT_RESET, devpriv->base_addr + P_MC1);

                /* DMA FIXME DMA// */
                DEBUG("s626_attach: DMA ALLOCATION\n");

                /* adc buffer allocation */
                devpriv->allocatedBuf = 0;

                devpriv->ANABuf.LogicalBase =
                    pci_alloc_consistent(devpriv->pdev, DMABUF_SIZE, &appdma);

                if (devpriv->ANABuf.LogicalBase == NULL) {
                        printk("s626_attach: DMA Memory mapping error\n");
                        return -ENOMEM;
                }

                devpriv->ANABuf.PhysicalBase = appdma;

                DEBUG
                    ("s626_attach: AllocDMAB ADC Logical=%p, bsize=%d, Physical=0x%x\n",
                     devpriv->ANABuf.LogicalBase, DMABUF_SIZE,
                     (uint32_t) devpriv->ANABuf.PhysicalBase);

                devpriv->allocatedBuf++;

                devpriv->RPSBuf.LogicalBase =
                    pci_alloc_consistent(devpriv->pdev, DMABUF_SIZE, &appdma);

                if (devpriv->RPSBuf.LogicalBase == NULL) {
                        printk("s626_attach: DMA Memory mapping error\n");
                        return -ENOMEM;
                }

                devpriv->RPSBuf.PhysicalBase = appdma;

                DEBUG
                    ("s626_attach: AllocDMAB RPS Logical=%p, bsize=%d, Physical=0x%x\n",
                     devpriv->RPSBuf.LogicalBase, DMABUF_SIZE,
                     (uint32_t) devpriv->RPSBuf.PhysicalBase);

                devpriv->allocatedBuf++;

        }

        dev->board_ptr = s626_boards;
        dev->board_name = thisboard->name;

        if (alloc_subdevices(dev, 6) < 0)
                return -ENOMEM;

        dev->iobase = (unsigned long)devpriv->base_addr;
        dev->irq = devpriv->pdev->irq;

        /* set up interrupt handler */
        if (dev->irq == 0) {
                printk(" unknown irq (bad)\n");
        } else {
                ret = request_irq(dev->irq, s626_irq_handler, IRQF_SHARED,
                                  "s626", dev);

                if (ret < 0) {
                        printk(" irq not available\n");
                        dev->irq = 0;
                }
        }

        DEBUG("s626_attach: -- it opts  %d,%d -- \n",
              it->options[0], it->options[1]);

        s = dev->subdevices + 0;
        /* analog input subdevice */
        dev->read_subdev = s;
        /* we support single-ended (ground) and differential */
        s->type = COMEDI_SUBD_AI;
        s->subdev_flags = SDF_READABLE | SDF_DIFF | SDF_CMD_READ;
        s->n_chan = thisboard->ai_chans;
        s->maxdata = (0xffff >> 2);
        s->range_table = &s626_range_table;
        s->len_chanlist = thisboard->ai_chans;  /* This is the maximum chanlist
                                                   length that the board can
                                                   handle */
        s->insn_config = s626_ai_insn_config;
        s->insn_read = s626_ai_insn_read;
        s->do_cmd = s626_ai_cmd;
        s->do_cmdtest = s626_ai_cmdtest;
        s->cancel = s626_ai_cancel;

        s = dev->subdevices + 1;
        /* analog output subdevice */
        s->type = COMEDI_SUBD_AO;
        s->subdev_flags = SDF_WRITABLE | SDF_READABLE;
        s->n_chan = thisboard->ao_chans;
        s->maxdata = (0x3fff);
        s->range_table = &range_bipolar10;
        s->insn_write = s626_ao_winsn;
        s->insn_read = s626_ao_rinsn;

        s = dev->subdevices + 2;
        /* digital I/O subdevice */
        s->type = COMEDI_SUBD_DIO;
        s->subdev_flags = SDF_WRITABLE | SDF_READABLE;
        s->n_chan = S626_DIO_CHANNELS;
        s->maxdata = 1;
        s->io_bits = 0xffff;
        s->private = &dio_private_A;
        s->range_table = &range_digital;
        s->insn_config = s626_dio_insn_config;
        s->insn_bits = s626_dio_insn_bits;

        s = dev->subdevices + 3;
        /* digital I/O subdevice */
        s->type = COMEDI_SUBD_DIO;
        s->subdev_flags = SDF_WRITABLE | SDF_READABLE;
        s->n_chan = 16;
        s->maxdata = 1;
        s->io_bits = 0xffff;
        s->private = &dio_private_B;
        s->range_table = &range_digital;
        s->insn_config = s626_dio_insn_config;
        s->insn_bits = s626_dio_insn_bits;

        s = dev->subdevices + 4;
        /* digital I/O subdevice */
        s->type = COMEDI_SUBD_DIO;
        s->subdev_flags = SDF_WRITABLE | SDF_READABLE;
        s->n_chan = 16;
        s->maxdata = 1;
        s->io_bits = 0xffff;
        s->private = &dio_private_C;
        s->range_table = &range_digital;
        s->insn_config = s626_dio_insn_config;
        s->insn_bits = s626_dio_insn_bits;

        s = dev->subdevices + 5;
        /* encoder (counter) subdevice */
        s->type = COMEDI_SUBD_COUNTER;
        s->subdev_flags = SDF_WRITABLE | SDF_READABLE | SDF_LSAMPL;
        s->n_chan = thisboard->enc_chans;
        s->private = enc_private_data;
        s->insn_config = s626_enc_insn_config;
        s->insn_read = s626_enc_insn_read;
        s->insn_write = s626_enc_insn_write;
        s->maxdata = 0xffffff;
        s->range_table = &range_unknown;

        /* stop ai_command */
        devpriv->ai_cmd_running = 0;

        if (devpriv->base_addr && (devpriv->allocatedBuf == 2)) {
                dma_addr_t pPhysBuf;
                uint16_t chan;

                /*  enab DEBI and audio pins, enable I2C interface. */
                MC_ENABLE(P_MC1, MC1_DEBI | MC1_AUDIO | MC1_I2C);
                /*  Configure DEBI operating mode. */
                WR7146(P_DEBICFG, DEBI_CFG_SLAVE16      /*  Local bus is 16 */
                       /*  bits wide. */
                       | (DEBI_TOUT << DEBI_CFG_TOUT_BIT)

                       /*  Declare DEBI */
                       /*  transfer timeout */
                       /*  interval. */
                       |DEBI_SWAP       /*  Set up byte lane */
                       /*  steering. */
                       | DEBI_CFG_INTEL);       /*  Intel-compatible */
                /*  local bus (DEBI */
                /*  never times out). */
                DEBUG("s626_attach: %d debi init -- %d\n",
                      DEBI_CFG_SLAVE16 | (DEBI_TOUT << DEBI_CFG_TOUT_BIT) |
                      DEBI_SWAP | DEBI_CFG_INTEL,
                      DEBI_CFG_INTEL | DEBI_CFG_TOQ | DEBI_CFG_INCQ |
                      DEBI_CFG_16Q);

                /* DEBI INIT S626 WR7146( P_DEBICFG, DEBI_CFG_INTEL | DEBI_CFG_TOQ */
                /* | DEBI_CFG_INCQ| DEBI_CFG_16Q); //end */

                /*  Paging is disabled. */
                WR7146(P_DEBIPAGE, DEBI_PAGE_DISABLE);  /*  Disable MMU paging. */

                /*  Init GPIO so that ADC Start* is negated. */
                WR7146(P_GPIO, GPIO_BASE | GPIO1_HI);

                /* IsBoardRevA is a boolean that indicates whether the board is RevA.
                 *
                 * VERSION 2.01 CHANGE: REV A & B BOARDS NOW SUPPORTED BY DYNAMIC
                 * EEPROM ADDRESS SELECTION.  Initialize the I2C interface, which
                 * is used to access the onboard serial EEPROM.  The EEPROM's I2C
                 * DeviceAddress is hardwired to a value that is dependent on the
                 * 626 board revision.  On all board revisions, the EEPROM stores
                 * TrimDAC calibration constants for analog I/O.  On RevB and
                 * higher boards, the DeviceAddress is hardwired to 0 to enable
                 * the EEPROM to also store the PCI SubVendorID and SubDeviceID;
                 * this is the address at which the SAA7146 expects a
                 * configuration EEPROM to reside.  On RevA boards, the EEPROM
                 * device address, which is hardwired to 4, prevents the SAA7146
                 * from retrieving PCI sub-IDs, so the SAA7146 uses its built-in
                 * default values, instead.
                 */

                /*     devpriv->I2Cards= IsBoardRevA ? 0xA8 : 0xA0; // Set I2C EEPROM */
                /*  DeviceType (0xA0) */
                /*  and DeviceAddress<<1. */

                devpriv->I2CAdrs = 0xA0;        /*  I2C device address for onboard */
                /*  eeprom(revb) */

                /*  Issue an I2C ABORT command to halt any I2C operation in */
                /* progress and reset BUSY flag. */
                WR7146(P_I2CSTAT, I2C_CLKSEL | I2C_ABORT);
                /*  Write I2C control: abort any I2C activity. */
                MC_ENABLE(P_MC2, MC2_UPLD_IIC);
                /*  Invoke command  upload */
                while ((RR7146(P_MC2) & MC2_UPLD_IIC) == 0) ;
                /*  and wait for upload to complete. */

                /* Per SAA7146 data sheet, write to STATUS reg twice to
                 * reset all  I2C error flags. */
                for (i = 0; i < 2; i++) {
                        WR7146(P_I2CSTAT, I2C_CLKSEL);
                        /*  Write I2C control: reset  error flags. */
                        MC_ENABLE(P_MC2, MC2_UPLD_IIC); /*  Invoke command upload */
                        while (!MC_TEST(P_MC2, MC2_UPLD_IIC)) ;
                        /* and wait for upload to complete. */
                }

                /* Init audio interface functional attributes: set DAC/ADC
                 * serial clock rates, invert DAC serial clock so that
                 * DAC data setup times are satisfied, enable DAC serial
                 * clock out.
                 */

                WR7146(P_ACON2, ACON2_INIT);

                /* Set up TSL1 slot list, which is used to control the
                 * accumulation of ADC data: RSD1 = shift data in on SD1.
                 * SIB_A1  = store data uint8_t at next available location in
                 * FB BUFFER1  register. */
                WR7146(P_TSL1, RSD1 | SIB_A1);
                /*  Fetch ADC high data uint8_t. */
                WR7146(P_TSL1 + 4, RSD1 | SIB_A1 | EOS);
                /*  Fetch ADC low data uint8_t; end of TSL1. */

                /*  enab TSL1 slot list so that it executes all the time. */
                WR7146(P_ACON1, ACON1_ADCSTART);

                /*  Initialize RPS registers used for ADC. */

                /* Physical start of RPS program. */
                WR7146(P_RPSADDR1, (uint32_t) devpriv->RPSBuf.PhysicalBase);

                WR7146(P_RPSPAGE1, 0);
                /*  RPS program performs no explicit mem writes. */
                WR7146(P_RPS1_TOUT, 0); /*  Disable RPS timeouts. */

                /* SAA7146 BUG WORKAROUND.  Initialize SAA7146 ADC interface
                 * to a known state by invoking ADCs until FB BUFFER 1
                 * register shows that it is correctly receiving ADC data.
                 * This is necessary because the SAA7146 ADC interface does
                 * not start up in a defined state after a PCI reset.
                 */

/*     PollList = EOPL;                 // Create a simple polling */
/*                                      // list for analog input */
/*                                      // channel 0. */
/*     ResetADC( dev, &PollList ); */

/*     s626_ai_rinsn(dev,dev->subdevices,NULL,data); //( &AdcData ); // */
/*                                                //Get initial ADC */
/*                                                //value. */

/*     StartVal = data[0]; */

/*     // VERSION 2.01 CHANGE: TIMEOUT ADDED TO PREVENT HANGED EXECUTION. */
/*     // Invoke ADCs until the new ADC value differs from the initial */
/*     // value or a timeout occurs.  The timeout protects against the */
/*     // possibility that the driver is restarting and the ADC data is a */
/*     // fixed value resulting from the applied ADC analog input being */
/*     // unusually quiet or at the rail. */

/*     for ( index = 0; index < 500; index++ ) */
/*       { */
/*      s626_ai_rinsn(dev,dev->subdevices,NULL,data); */
/*      AdcData = data[0];      //ReadADC(  &AdcData ); */
/*      if ( AdcData != StartVal ) */
/*        break; */
/*       } */

                /*  end initADC */

                /*  init the DAC interface */

                /* Init Audio2's output DMAC attributes: burst length = 1
                 * DWORD,  threshold = 1 DWORD.
                 */
                WR7146(P_PCI_BT_A, 0);

                /* Init Audio2's output DMA physical addresses.  The protection
                 * address is set to 1 DWORD past the base address so that a
                 * single DWORD will be transferred each time a DMA transfer is
                 * enabled. */

                pPhysBuf =
                    devpriv->ANABuf.PhysicalBase +
                    (DAC_WDMABUF_OS * sizeof(uint32_t));

                WR7146(P_BASEA2_OUT, (uint32_t) pPhysBuf);      /*  Buffer base adrs. */
                WR7146(P_PROTA2_OUT, (uint32_t) (pPhysBuf + sizeof(uint32_t))); /*  Protection address. */

                /* Cache Audio2's output DMA buffer logical address.  This is
                 * where DAC data is buffered for A2 output DMA transfers. */
                devpriv->pDacWBuf =
                    (uint32_t *) devpriv->ANABuf.LogicalBase + DAC_WDMABUF_OS;

                /* Audio2's output channels does not use paging.  The protection
                 * violation handling bit is set so that the DMAC will
                 * automatically halt and its PCI address pointer will be reset
                 * when the protection address is reached. */

                WR7146(P_PAGEA2_OUT, 8);

                /* Initialize time slot list 2 (TSL2), which is used to control
                 * the clock generation for and serialization of data to be sent
                 * to the DAC devices.  Slot 0 is a NOP that is used to trap TSL
                 * execution; this permits other slots to be safely modified
                 * without first turning off the TSL sequencer (which is
                 * apparently impossible to do).  Also, SD3 (which is driven by a
                 * pull-up resistor) is shifted in and stored to the MSB of
                 * FB_BUFFER2 to be used as evidence that the slot sequence has
                 * not yet finished executing.
                 */

                SETVECT(0, XSD2 | RSD3 | SIB_A2 | EOS);
                /*  Slot 0: Trap TSL execution, shift 0xFF into FB_BUFFER2. */

                /* Initialize slot 1, which is constant.  Slot 1 causes a
                 * DWORD to be transferred from audio channel 2's output FIFO
                 * to the FIFO's output buffer so that it can be serialized
                 * and sent to the DAC during subsequent slots.  All remaining
                 * slots are dynamically populated as required by the target
                 * DAC device.
                 */
                SETVECT(1, LF_A2);
                /*  Slot 1: Fetch DWORD from Audio2's output FIFO. */

                /*  Start DAC's audio interface (TSL2) running. */
                WR7146(P_ACON1, ACON1_DACSTART);

                /* end init DAC interface */

                /* Init Trim DACs to calibrated values.  Do it twice because the
                 * SAA7146 audio channel does not always reset properly and
                 * sometimes causes the first few TrimDAC writes to malfunction.
                 */

                LoadTrimDACs(dev);
                LoadTrimDACs(dev);      /*  Insurance. */

                /* Manually init all gate array hardware in case this is a soft
                 * reset (we have no way of determining whether this is a warm
                 * or cold start).  This is necessary because the gate array will
                 * reset only in response to a PCI hard reset; there is no soft
                 * reset function. */

                /* Init all DAC outputs to 0V and init all DAC setpoint and
                 * polarity images.
                 */
                for (chan = 0; chan < S626_DAC_CHANNELS; chan++)
                        SetDAC(dev, chan, 0);

                /* Init image of WRMISC2 Battery Charger Enabled control bit.
                 * This image is used when the state of the charger control bit,
                 * which has no direct hardware readback mechanism, is queried.
                 */
                devpriv->ChargeEnabled = 0;

                /* Init image of watchdog timer interval in WRMISC2.  This image
                 * maintains the value of the control bits of MISC2 are
                 * continuously reset to zero as long as the WD timer is disabled.
                 */
                devpriv->WDInterval = 0;

                /* Init Counter Interrupt enab mask for RDMISC2.  This mask is
                 * applied against MISC2 when testing to determine which timer
                 * events are requesting interrupt service.
                 */
                devpriv->CounterIntEnabs = 0;

                /*  Init counters. */
                CountersInit(dev);

                /* Without modifying the state of the Battery Backup enab, disable
                 * the watchdog timer, set DIO channels 0-5 to operate in the
                 * standard DIO (vs. counter overflow) mode, disable the battery
                 * charger, and reset the watchdog interval selector to zero.
                 */
                WriteMISC2(dev, (uint16_t) (DEBIread(dev,
                                                     LP_RDMISC2) &
                                            MISC2_BATT_ENABLE));

                /*  Initialize the digital I/O subsystem. */
                s626_dio_init(dev);

                /* enable interrupt test */
                /*  writel(IRQ_GPIO3 | IRQ_RPS1,devpriv->base_addr+P_IER); */
        }

        DEBUG("s626_attach: comedi%d s626 attached %04x\n", dev->minor,
              (uint32_t) devpriv->base_addr);

        return 1;
}

static unsigned int s626_ai_reg_to_uint(int data)
{
        unsigned int tempdata;

        tempdata = (data >> 18);
        if (tempdata & 0x2000)
                tempdata &= 0x1fff;
        else
                tempdata += (1 << 13);

        return tempdata;
}

/* static unsigned int s626_uint_to_reg(struct comedi_subdevice *s, int data){ */
/*   return 0; */
/* } */

static irqreturn_t s626_irq_handler(int irq, void *d)
{

        struct comedi_device *dev = d;
        struct comedi_subdevice *s;
        struct comedi_cmd *cmd;
        struct enc_private *k;
        unsigned long flags;
        int32_t *readaddr;
        uint32_t irqtype, irqstatus;
        int i = 0;
        short tempdata;
        uint8_t group;
        uint16_t irqbit;

        DEBUG("s626_irq_handler: interrupt request recieved!!!\n");

        if (dev->attached == 0)
                return IRQ_NONE;
        /*  lock to avoid race with comedi_poll */
        spin_lock_irqsave(&dev->spinlock, flags);

        /* save interrupt enable register state */
        irqstatus = readl(devpriv->base_addr + P_IER);

        /* read interrupt type */
        irqtype = readl(devpriv->base_addr + P_ISR);

        /* disable master interrupt */
        writel(0, devpriv->base_addr + P_IER);

        /* clear interrupt */
        writel(irqtype, devpriv->base_addr + P_ISR);

        /* do somethings */
        DEBUG("s626_irq_handler: interrupt type %d\n", irqtype);

        switch (irqtype) {
        case IRQ_RPS1:          /*  end_of_scan occurs */

                DEBUG("s626_irq_handler: RPS1 irq detected\n");

                /*  manage ai subdevice */
                s = dev->subdevices;
                cmd = &(s->async->cmd);

                /* Init ptr to DMA buffer that holds new ADC data.  We skip the
                 * first uint16_t in the buffer because it contains junk data from
                 * the final ADC of the previous poll list scan.
                 */
                readaddr = (int32_t *) devpriv->ANABuf.LogicalBase + 1;

                /*  get the data and hand it over to comedi */
                for (i = 0; i < (s->async->cmd.chanlist_len); i++) {
                        /*  Convert ADC data to 16-bit integer values and copy to application */
                        /*  buffer. */
                        tempdata = s626_ai_reg_to_uint((int)*readaddr);
                        readaddr++;

                        /* put data into read buffer */
                        /*  comedi_buf_put(s->async, tempdata); */
                        if (cfc_write_to_buffer(s, tempdata) == 0)
                                printk
                                    ("s626_irq_handler: cfc_write_to_buffer error!\n");

                        DEBUG("s626_irq_handler: ai channel %d acquired: %d\n",
                              i, tempdata);
                }

                /* end of scan occurs */
                s->async->events |= COMEDI_CB_EOS;

                if (!(devpriv->ai_continous))
                        devpriv->ai_sample_count--;
                if (devpriv->ai_sample_count <= 0) {
                        devpriv->ai_cmd_running = 0;

                        /*  Stop RPS program. */
                        MC_DISABLE(P_MC1, MC1_ERPS1);

                        /* send end of acquisition */
                        s->async->events |= COMEDI_CB_EOA;

                        /* disable master interrupt */
                        irqstatus = 0;
                }

                if (devpriv->ai_cmd_running && cmd->scan_begin_src == TRIG_EXT) {
                        DEBUG
                            ("s626_irq_handler: enable interrupt on dio channel %d\n",
                             cmd->scan_begin_arg);

                        s626_dio_set_irq(dev, cmd->scan_begin_arg);

                        DEBUG("s626_irq_handler: External trigger is set!!!\n");
                }
                /*  tell comedi that data is there */
                DEBUG("s626_irq_handler: events %d\n", s->async->events);
                comedi_event(dev, s);
                break;
        case IRQ_GPIO3: /* check dio and conter interrupt */

                DEBUG("s626_irq_handler: GPIO3 irq detected\n");

                /*  manage ai subdevice */
                s = dev->subdevices;
                cmd = &(s->async->cmd);

                /* s626_dio_clear_irq(dev); */

                for (group = 0; group < S626_DIO_BANKS; group++) {
                        irqbit = 0;
                        /* read interrupt type */
                        irqbit = DEBIread(dev,
                                          ((struct dio_private *)(dev->
                                                                  subdevices +
                                                                  2 +
                                                                  group)->
                                           private)->RDCapFlg);

                        /* check if interrupt is generated from dio channels */
                        if (irqbit) {
                                s626_dio_reset_irq(dev, group, irqbit);
                                DEBUG
                                    ("s626_irq_handler: check interrupt on dio group %d %d\n",
                                     group, i);
                                if (devpriv->ai_cmd_running) {
                                        /* check if interrupt is an ai acquisition start trigger */
                                        if ((irqbit >> (cmd->start_arg -
                                                        (16 * group)))
                                            == 1 && cmd->start_src == TRIG_EXT) {
                                                DEBUG
                                                    ("s626_irq_handler: Edge capture interrupt recieved from channel %d\n",
                                                     cmd->start_arg);

                                                /*  Start executing the RPS program. */
                                                MC_ENABLE(P_MC1, MC1_ERPS1);

                                                DEBUG
                                                    ("s626_irq_handler: aquisition start triggered!!!\n");

                                                if (cmd->scan_begin_src ==
                                                    TRIG_EXT) {
                                                        DEBUG
                                                            ("s626_ai_cmd: enable interrupt on dio channel %d\n",
                                                             cmd->
                                                             scan_begin_arg);

                                                        s626_dio_set_irq(dev,
                                                                         cmd->scan_begin_arg);

                                                        DEBUG
                                                            ("s626_irq_handler: External scan trigger is set!!!\n");
                                                }
                                        }
                                        if ((irqbit >> (cmd->scan_begin_arg -
                                                        (16 * group)))
                                            == 1
                                            && cmd->scan_begin_src ==
                                            TRIG_EXT) {
                                                DEBUG
                                                    ("s626_irq_handler: Edge capture interrupt recieved from channel %d\n",
                                                     cmd->scan_begin_arg);

                                                /*  Trigger ADC scan loop start by setting RPS Signal 0. */
                                                MC_ENABLE(P_MC2, MC2_ADC_RPS);

                                                DEBUG
                                                    ("s626_irq_handler: scan triggered!!! %d\n",
                                                     devpriv->ai_sample_count);
                                                if (cmd->convert_src ==
                                                    TRIG_EXT) {

                                                        DEBUG
                                                            ("s626_ai_cmd: enable interrupt on dio channel %d group %d\n",
                                                             cmd->convert_arg -
                                                             (16 * group),
                                                             group);

                                                        devpriv->ai_convert_count
                                                            = cmd->chanlist_len;

                                                        s626_dio_set_irq(dev,
                                                                         cmd->convert_arg);

                                                        DEBUG
                                                            ("s626_irq_handler: External convert trigger is set!!!\n");
                                                }

                                                if (cmd->convert_src ==
                                                    TRIG_TIMER) {
                                                        k = &encpriv[5];
                                                        devpriv->ai_convert_count
                                                            = cmd->chanlist_len;
                                                        k->SetEnable(dev, k,
                                                                     CLKENAB_ALWAYS);
                                                }
                                        }
                                        if ((irqbit >> (cmd->convert_arg -
                                                        (16 * group)))
                                            == 1
                                            && cmd->convert_src == TRIG_EXT) {
                                                DEBUG
                                                    ("s626_irq_handler: Edge capture interrupt recieved from channel %d\n",
                                                     cmd->convert_arg);

                                                /*  Trigger ADC scan loop start by setting RPS Signal 0. */
                                                MC_ENABLE(P_MC2, MC2_ADC_RPS);

                                                DEBUG
                                                    ("s626_irq_handler: adc convert triggered!!!\n");

                                                devpriv->ai_convert_count--;

                                                if (devpriv->ai_convert_count >
                                                    0) {

                                                        DEBUG
                                                            ("s626_ai_cmd: enable interrupt on dio channel %d group %d\n",
                                                             cmd->convert_arg -
                                                             (16 * group),
                                                             group);

                                                        s626_dio_set_irq(dev,
                                                                         cmd->convert_arg);

                                                        DEBUG
                                                            ("s626_irq_handler: External trigger is set!!!\n");
                                                }
                                        }
                                }
                                break;
                        }
                }

                /* read interrupt type */
                irqbit = DEBIread(dev, LP_RDMISC2);

                /* check interrupt on counters */
                DEBUG("s626_irq_handler: check counters interrupt %d\n",
                      irqbit);

                if (irqbit & IRQ_COINT1A) {
                        DEBUG
                            ("s626_irq_handler: interrupt on counter 1A overflow\n");
                        k = &encpriv[0];

                        /* clear interrupt capture flag */
                        k->ResetCapFlags(dev, k);
                }
                if (irqbit & IRQ_COINT2A) {
                        DEBUG
                            ("s626_irq_handler: interrupt on counter 2A overflow\n");
                        k = &encpriv[1];

                        /* clear interrupt capture flag */
                        k->ResetCapFlags(dev, k);
                }
                if (irqbit & IRQ_COINT3A) {
                        DEBUG
                            ("s626_irq_handler: interrupt on counter 3A overflow\n");
                        k = &encpriv[2];

                        /* clear interrupt capture flag */
                        k->ResetCapFlags(dev, k);
                }
                if (irqbit & IRQ_COINT1B) {
                        DEBUG
                            ("s626_irq_handler: interrupt on counter 1B overflow\n");
                        k = &encpriv[3];

                        /* clear interrupt capture flag */
                        k->ResetCapFlags(dev, k);
                }
                if (irqbit & IRQ_COINT2B) {
                        DEBUG
                            ("s626_irq_handler: interrupt on counter 2B overflow\n");
                        k = &encpriv[4];

                        /* clear interrupt capture flag */
                        k->ResetCapFlags(dev, k);

                        if (devpriv->ai_convert_count > 0) {
                                devpriv->ai_convert_count--;
                                if (devpriv->ai_convert_count == 0)
                                        k->SetEnable(dev, k, CLKENAB_INDEX);

                                if (cmd->convert_src == TRIG_TIMER) {
                                        DEBUG
                                            ("s626_irq_handler: conver timer trigger!!! %d\n",
                                             devpriv->ai_convert_count);

                                        /*  Trigger ADC scan loop start by setting RPS Signal 0. */
                                        MC_ENABLE(P_MC2, MC2_ADC_RPS);
                                }
                        }
                }
                if (irqbit & IRQ_COINT3B) {
                        DEBUG
                            ("s626_irq_handler: interrupt on counter 3B overflow\n");
                        k = &encpriv[5];

                        /* clear interrupt capture flag */
                        k->ResetCapFlags(dev, k);

                        if (cmd->scan_begin_src == TRIG_TIMER) {
                                DEBUG
                                    ("s626_irq_handler: scan timer trigger!!!\n");

                                /*  Trigger ADC scan loop start by setting RPS Signal 0. */
                                MC_ENABLE(P_MC2, MC2_ADC_RPS);
                        }

                        if (cmd->convert_src == TRIG_TIMER) {
                                DEBUG
                                    ("s626_irq_handler: convert timer trigger is set\n");
                                k = &encpriv[4];
                                devpriv->ai_convert_count = cmd->chanlist_len;
                                k->SetEnable(dev, k, CLKENAB_ALWAYS);
                        }
                }
        }

        /* enable interrupt */
        writel(irqstatus, devpriv->base_addr + P_IER);

        DEBUG("s626_irq_handler: exit interrupt service routine.\n");

        spin_unlock_irqrestore(&dev->spinlock, flags);
        return IRQ_HANDLED;
}

static int s626_detach(struct comedi_device *dev)
{
        if (devpriv) {
                /* stop ai_command */
                devpriv->ai_cmd_running = 0;

                if (devpriv->base_addr) {
                        /* interrupt mask */
                        WR7146(P_IER, 0);       /*  Disable master interrupt. */
                        WR7146(P_ISR, IRQ_GPIO3 | IRQ_RPS1);    /*  Clear board's IRQ status flag. */

                        /*  Disable the watchdog timer and battery charger. */
                        WriteMISC2(dev, 0);

                        /*  Close all interfaces on 7146 device. */
                        WR7146(P_MC1, MC1_SHUTDOWN);
                        WR7146(P_ACON1, ACON1_BASE);

                        CloseDMAB(dev, &devpriv->RPSBuf, DMABUF_SIZE);
                        CloseDMAB(dev, &devpriv->ANABuf, DMABUF_SIZE);
                }

                if (dev->irq)
                        free_irq(dev->irq, dev);

                if (devpriv->base_addr)
                        iounmap(devpriv->base_addr);

                if (devpriv->pdev) {
                        if (devpriv->got_regions)
                                comedi_pci_disable(devpriv->pdev);
                        pci_dev_put(devpriv->pdev);
                }
        }

        DEBUG("s626_detach: S626 detached!\n");

        return 0;
}

/*
 * this functions build the RPS program for hardware driven acquistion
 */
void ResetADC(struct comedi_device *dev, uint8_t * ppl)
{
        register uint32_t *pRPS;
        uint32_t JmpAdrs;
        uint16_t i;
        uint16_t n;
        uint32_t LocalPPL;
        struct comedi_cmd *cmd = &(dev->subdevices->async->cmd);

        /*  Stop RPS program in case it is currently running. */
        MC_DISABLE(P_MC1, MC1_ERPS1);

        /*  Set starting logical address to write RPS commands. */
        pRPS = (uint32_t *) devpriv->RPSBuf.LogicalBase;

        /*  Initialize RPS instruction pointer. */
        WR7146(P_RPSADDR1, (uint32_t) devpriv->RPSBuf.PhysicalBase);

        /*  Construct RPS program in RPSBuf DMA buffer */

        if (cmd != NULL && cmd->scan_begin_src != TRIG_FOLLOW) {
                DEBUG("ResetADC: scan_begin pause inserted\n");
                /*  Wait for Start trigger. */
                *pRPS++ = RPS_PAUSE | RPS_SIGADC;
                *pRPS++ = RPS_CLRSIGNAL | RPS_SIGADC;
        }

        /* SAA7146 BUG WORKAROUND Do a dummy DEBI Write.  This is necessary
         * because the first RPS DEBI Write following a non-RPS DEBI write
         * seems to always fail.  If we don't do this dummy write, the ADC
         * gain might not be set to the value required for the first slot in
         * the poll list; the ADC gain would instead remain unchanged from
         * the previously programmed value.
         */
        *pRPS++ = RPS_LDREG | (P_DEBICMD >> 2);
        /* Write DEBI Write command and address to shadow RAM. */

        *pRPS++ = DEBI_CMD_WRWORD | LP_GSEL;
        *pRPS++ = RPS_LDREG | (P_DEBIAD >> 2);
        /*  Write DEBI immediate data  to shadow RAM: */

        *pRPS++ = GSEL_BIPOLAR5V;
        /*  arbitrary immediate data  value. */

        *pRPS++ = RPS_CLRSIGNAL | RPS_DEBI;
        /*  Reset "shadow RAM  uploaded" flag. */
        *pRPS++ = RPS_UPLOAD | RPS_DEBI;        /*  Invoke shadow RAM upload. */
        *pRPS++ = RPS_PAUSE | RPS_DEBI; /*  Wait for shadow upload to finish. */

        /* Digitize all slots in the poll list. This is implemented as a
         * for loop to limit the slot count to 16 in case the application
         * forgot to set the EOPL flag in the final slot.
         */
        for (devpriv->AdcItems = 0; devpriv->AdcItems < 16; devpriv->AdcItems++) {
                /* Convert application's poll list item to private board class
                 * format.  Each app poll list item is an uint8_t with form
                 * (EOPL,x,x,RANGE,CHAN<3:0>), where RANGE code indicates 0 =
                 * +-10V, 1 = +-5V, and EOPL = End of Poll List marker.
                 */
                LocalPPL =
                    (*ppl << 8) | (*ppl & 0x10 ? GSEL_BIPOLAR5V :
                                   GSEL_BIPOLAR10V);

                /*  Switch ADC analog gain. */
                *pRPS++ = RPS_LDREG | (P_DEBICMD >> 2); /*  Write DEBI command */
                /*  and address to */
                /*  shadow RAM. */
                *pRPS++ = DEBI_CMD_WRWORD | LP_GSEL;
                *pRPS++ = RPS_LDREG | (P_DEBIAD >> 2);  /*  Write DEBI */
                /*  immediate data to */
                /*  shadow RAM. */
                *pRPS++ = LocalPPL;
                *pRPS++ = RPS_CLRSIGNAL | RPS_DEBI;     /*  Reset "shadow RAM uploaded" */
                /*  flag. */
                *pRPS++ = RPS_UPLOAD | RPS_DEBI;        /*  Invoke shadow RAM upload. */
                *pRPS++ = RPS_PAUSE | RPS_DEBI; /*  Wait for shadow upload to */
                /*  finish. */

                /*  Select ADC analog input channel. */
                *pRPS++ = RPS_LDREG | (P_DEBICMD >> 2);
                /*  Write DEBI command and address to  shadow RAM. */
                *pRPS++ = DEBI_CMD_WRWORD | LP_ISEL;
                *pRPS++ = RPS_LDREG | (P_DEBIAD >> 2);
                /*  Write DEBI immediate data to shadow RAM. */
                *pRPS++ = LocalPPL;
                *pRPS++ = RPS_CLRSIGNAL | RPS_DEBI;
                /*  Reset "shadow RAM uploaded"  flag. */

                *pRPS++ = RPS_UPLOAD | RPS_DEBI;
                /*  Invoke shadow RAM upload. */

                *pRPS++ = RPS_PAUSE | RPS_DEBI;
                /*  Wait for shadow upload to finish. */

                /* Delay at least 10 microseconds for analog input settling.
                 * Instead of padding with NOPs, we use RPS_JUMP instructions
                 * here; this allows us to produce a longer delay than is
                 * possible with NOPs because each RPS_JUMP flushes the RPS'
                 * instruction prefetch pipeline.
                 */
                JmpAdrs =
                    (uint32_t) devpriv->RPSBuf.PhysicalBase +
                    (uint32_t) ((unsigned long)pRPS -
                                (unsigned long)devpriv->RPSBuf.LogicalBase);
                for (i = 0; i < (10 * RPSCLK_PER_US / 2); i++) {
                        JmpAdrs += 8;   /*  Repeat to implement time delay: */
                        *pRPS++ = RPS_JUMP;     /*  Jump to next RPS instruction. */
                        *pRPS++ = JmpAdrs;
                }

                if (cmd != NULL && cmd->convert_src != TRIG_NOW) {
                        DEBUG("ResetADC: convert pause inserted\n");
                        /*  Wait for Start trigger. */
                        *pRPS++ = RPS_PAUSE | RPS_SIGADC;
                        *pRPS++ = RPS_CLRSIGNAL | RPS_SIGADC;
                }
                /*  Start ADC by pulsing GPIO1. */
                *pRPS++ = RPS_LDREG | (P_GPIO >> 2);    /*  Begin ADC Start pulse. */
                *pRPS++ = GPIO_BASE | GPIO1_LO;
                *pRPS++ = RPS_NOP;
                /*  VERSION 2.03 CHANGE: STRETCH OUT ADC START PULSE. */
                *pRPS++ = RPS_LDREG | (P_GPIO >> 2);    /*  End ADC Start pulse. */
                *pRPS++ = GPIO_BASE | GPIO1_HI;

                /* Wait for ADC to complete (GPIO2 is asserted high when ADC not
                 * busy) and for data from previous conversion to shift into FB
                 * BUFFER 1 register.
                 */
                *pRPS++ = RPS_PAUSE | RPS_GPIO2;        /*  Wait for ADC done. */

                /*  Transfer ADC data from FB BUFFER 1 register to DMA buffer. */
                *pRPS++ = RPS_STREG | (BUGFIX_STREG(P_FB_BUFFER1) >> 2);
                *pRPS++ =
                    (uint32_t) devpriv->ANABuf.PhysicalBase +
                    (devpriv->AdcItems << 2);

                /*  If this slot's EndOfPollList flag is set, all channels have */
                /*  now been processed. */
                if (*ppl++ & EOPL) {
                        devpriv->AdcItems++;    /*  Adjust poll list item count. */
                        break;  /*  Exit poll list processing loop. */
                }
        }
        DEBUG("ResetADC: ADC items %d \n", devpriv->AdcItems);

        /* VERSION 2.01 CHANGE: DELAY CHANGED FROM 250NS to 2US.  Allow the
         * ADC to stabilize for 2 microseconds before starting the final
         * (dummy) conversion.  This delay is necessary to allow sufficient
         * time between last conversion finished and the start of the dummy
         * conversion.  Without this delay, the last conversion's data value
         * is sometimes set to the previous conversion's data value.
         */
        for (n = 0; n < (2 * RPSCLK_PER_US); n++)
                *pRPS++ = RPS_NOP;

        /* Start a dummy conversion to cause the data from the last
         * conversion of interest to be shifted in.
         */
        *pRPS++ = RPS_LDREG | (P_GPIO >> 2);    /*  Begin ADC Start pulse. */
        *pRPS++ = GPIO_BASE | GPIO1_LO;
        *pRPS++ = RPS_NOP;
        /* VERSION 2.03 CHANGE: STRETCH OUT ADC START PULSE. */
        *pRPS++ = RPS_LDREG | (P_GPIO >> 2);    /*  End ADC Start pulse. */
        *pRPS++ = GPIO_BASE | GPIO1_HI;

        /* Wait for the data from the last conversion of interest to arrive
         * in FB BUFFER 1 register.
         */
        *pRPS++ = RPS_PAUSE | RPS_GPIO2;        /*  Wait for ADC done. */

        /*  Transfer final ADC data from FB BUFFER 1 register to DMA buffer. */
        *pRPS++ = RPS_STREG | (BUGFIX_STREG(P_FB_BUFFER1) >> 2);        /*  */
        *pRPS++ =
            (uint32_t) devpriv->ANABuf.PhysicalBase + (devpriv->AdcItems << 2);

        /*  Indicate ADC scan loop is finished. */
        /*  *pRPS++= RPS_CLRSIGNAL | RPS_SIGADC ;  // Signal ReadADC() that scan is done. */

        /* invoke interrupt */
        if (devpriv->ai_cmd_running == 1) {
                DEBUG("ResetADC: insert irq in ADC RPS task\n");
                *pRPS++ = RPS_IRQ;
        }
        /*  Restart RPS program at its beginning. */
        *pRPS++ = RPS_JUMP;     /*  Branch to start of RPS program. */
        *pRPS++ = (uint32_t) devpriv->RPSBuf.PhysicalBase;

        /*  End of RPS program build */
}

/* TO COMPLETE, IF NECESSARY */
static int s626_ai_insn_config(struct comedi_device *dev,
                               struct comedi_subdevice *s,
                               struct comedi_insn *insn, unsigned int *data)
{

        return -EINVAL;
}

/* static int s626_ai_rinsn(struct comedi_device *dev,struct comedi_subdevice *s,struct comedi_insn *insn,unsigned int *data) */
/* { */
/*   register uint8_t   i; */
/*   register int32_t   *readaddr; */

/*   DEBUG("as626_ai_rinsn: ai_rinsn enter \n");  */

/*   Trigger ADC scan loop start by setting RPS Signal 0. */
/*   MC_ENABLE( P_MC2, MC2_ADC_RPS ); */

/*   Wait until ADC scan loop is finished (RPS Signal 0 reset). */
/*   while ( MC_TEST( P_MC2, MC2_ADC_RPS ) ); */

/* Init ptr to DMA buffer that holds new ADC data.  We skip the
 * first uint16_t in the buffer because it contains junk data from
 * the final ADC of the previous poll list scan.
 */
/*   readaddr = (uint32_t *)devpriv->ANABuf.LogicalBase + 1; */

/*  Convert ADC data to 16-bit integer values and copy to application buffer. */
/*   for ( i = 0; i < devpriv->AdcItems; i++ ) { */
/*     *data = s626_ai_reg_to_uint( *readaddr++ ); */
/*     DEBUG("s626_ai_rinsn: data %d \n",*data); */
/*     data++; */
/*   } */

/*   DEBUG("s626_ai_rinsn: ai_rinsn escape \n"); */
/*   return i; */
/* } */

static int s626_ai_insn_read(struct comedi_device *dev,
                             struct comedi_subdevice *s,
                             struct comedi_insn *insn, unsigned int *data)
{
        uint16_t chan = CR_CHAN(insn->chanspec);
        uint16_t range = CR_RANGE(insn->chanspec);
        uint16_t AdcSpec = 0;
        uint32_t GpioImage;
        int n;

        /* interrupt call test  */
/*   writel(IRQ_GPIO3,devpriv->base_addr+P_PSR); */
        /* Writing a logical 1 into any of the RPS_PSR bits causes the
         * corresponding interrupt to be generated if enabled
         */

        DEBUG("s626_ai_insn_read: entering\n");

        /* Convert application's ADC specification into form
         *  appropriate for register programming.
         */
        if (range == 0)
                AdcSpec = (chan << 8) | (GSEL_BIPOLAR5V);
        else
                AdcSpec = (chan << 8) | (GSEL_BIPOLAR10V);

        /*  Switch ADC analog gain. */
        DEBIwrite(dev, LP_GSEL, AdcSpec);       /*  Set gain. */

        /*  Select ADC analog input channel. */
        DEBIwrite(dev, LP_ISEL, AdcSpec);       /*  Select channel. */

        for (n = 0; n < insn->n; n++) {

                /*  Delay 10 microseconds for analog input settling. */
                udelay(10);

                /*  Start ADC by pulsing GPIO1 low. */
                GpioImage = RR7146(P_GPIO);
                /*  Assert ADC Start command */
                WR7146(P_GPIO, GpioImage & ~GPIO1_HI);
                /*    and stretch it out. */
                WR7146(P_GPIO, GpioImage & ~GPIO1_HI);
                WR7146(P_GPIO, GpioImage & ~GPIO1_HI);
                /*  Negate ADC Start command. */
                WR7146(P_GPIO, GpioImage | GPIO1_HI);

                /*  Wait for ADC to complete (GPIO2 is asserted high when */
                /*  ADC not busy) and for data from previous conversion to */
                /*  shift into FB BUFFER 1 register. */

                /*  Wait for ADC done. */
                while (!(RR7146(P_PSR) & PSR_GPIO2)) ;

                /*  Fetch ADC data. */
                if (n != 0)
                        data[n - 1] = s626_ai_reg_to_uint(RR7146(P_FB_BUFFER1));

                /* Allow the ADC to stabilize for 4 microseconds before
                 * starting the next (final) conversion.  This delay is
                 * necessary to allow sufficient time between last
                 * conversion finished and the start of the next
                 * conversion.  Without this delay, the last conversion's
                 * data value is sometimes set to the previous
                 * conversion's data value.
                 */
                udelay(4);
        }

        /* Start a dummy conversion to cause the data from the
         * previous conversion to be shifted in. */
        GpioImage = RR7146(P_GPIO);

        /* Assert ADC Start command */
        WR7146(P_GPIO, GpioImage & ~GPIO1_HI);
        /*    and stretch it out. */
        WR7146(P_GPIO, GpioImage & ~GPIO1_HI);
        WR7146(P_GPIO, GpioImage & ~GPIO1_HI);
        /*  Negate ADC Start command. */
        WR7146(P_GPIO, GpioImage | GPIO1_HI);

        /*  Wait for the data to arrive in FB BUFFER 1 register. */

        /*  Wait for ADC done. */
        while (!(RR7146(P_PSR) & PSR_GPIO2)) ;

        /*  Fetch ADC data from audio interface's input shift register. */

        /*  Fetch ADC data. */
        if (n != 0)
                data[n - 1] = s626_ai_reg_to_uint(RR7146(P_FB_BUFFER1));

        DEBUG("s626_ai_insn_read: samples %d, data %d\n", n, data[n - 1]);

        return n;
}

static int s626_ai_load_polllist(uint8_t * ppl, struct comedi_cmd *cmd)
{

        int n;

        for (n = 0; n < cmd->chanlist_len; n++) {
                if (CR_RANGE((cmd->chanlist)[n]) == 0)
                        ppl[n] = (CR_CHAN((cmd->chanlist)[n])) | (RANGE_5V);
                else
                        ppl[n] = (CR_CHAN((cmd->chanlist)[n])) | (RANGE_10V);
        }
        if (n != 0)
                ppl[n - 1] |= EOPL;

        return n;
}

static int s626_ai_inttrig(struct comedi_device *dev,
                           struct comedi_subdevice *s, unsigned int trignum)
{
        if (trignum != 0)
                return -EINVAL;

        DEBUG("s626_ai_inttrig: trigger adc start...");

        /*  Start executing the RPS program. */
        MC_ENABLE(P_MC1, MC1_ERPS1);

        s->async->inttrig = NULL;

        DEBUG(" done\n");

        return 1;
}

/*  TO COMPLETE  */
static int s626_ai_cmd(struct comedi_device *dev, struct comedi_subdevice *s)
{

        uint8_t ppl[16];
        struct comedi_cmd *cmd = &s->async->cmd;
        struct enc_private *k;
        int tick;

        DEBUG("s626_ai_cmd: entering command function\n");

        if (devpriv->ai_cmd_running) {
                printk("s626_ai_cmd: Another ai_cmd is running %d\n",
                       dev->minor);
                return -EBUSY;
        }
        /* disable interrupt */
        writel(0, devpriv->base_addr + P_IER);

        /* clear interrupt request */
        writel(IRQ_RPS1 | IRQ_GPIO3, devpriv->base_addr + P_ISR);

        /* clear any pending interrupt */
        s626_dio_clear_irq(dev);
        /*   s626_enc_clear_irq(dev); */

        /* reset ai_cmd_running flag */
        devpriv->ai_cmd_running = 0;

        /*  test if cmd is valid */
        if (cmd == NULL) {
                DEBUG("s626_ai_cmd: NULL command\n");
                return -EINVAL;
        } else {
                DEBUG("s626_ai_cmd: command recieved!!!\n");
        }

        if (dev->irq == 0) {
                comedi_error(dev,
                             "s626_ai_cmd: cannot run command without an irq");
                return -EIO;
        }

        s626_ai_load_polllist(ppl, cmd);
        devpriv->ai_cmd_running = 1;
        devpriv->ai_convert_count = 0;

        switch (cmd->scan_begin_src) {
        case TRIG_FOLLOW:
                break;
        case TRIG_TIMER:
                /*  set a conter to generate adc trigger at scan_begin_arg interval */
                k = &encpriv[5];
                tick = s626_ns_to_timer((int *)&cmd->scan_begin_arg,
                                        cmd->flags & TRIG_ROUND_MASK);

                /* load timer value and enable interrupt */
                s626_timer_load(dev, k, tick);
                k->SetEnable(dev, k, CLKENAB_ALWAYS);

                DEBUG("s626_ai_cmd: scan trigger timer is set with value %d\n",
                      tick);

                break;
        case TRIG_EXT:
                /*  set the digital line and interrupt for scan trigger */
                if (cmd->start_src != TRIG_EXT)
                        s626_dio_set_irq(dev, cmd->scan_begin_arg);

                DEBUG("s626_ai_cmd: External scan trigger is set!!!\n");

                break;
        }

        switch (cmd->convert_src) {
        case TRIG_NOW:
                break;
        case TRIG_TIMER:
                /*  set a conter to generate adc trigger at convert_arg interval */
                k = &encpriv[4];
                tick = s626_ns_to_timer((int *)&cmd->convert_arg,
                                        cmd->flags & TRIG_ROUND_MASK);

                /* load timer value and enable interrupt */
                s626_timer_load(dev, k, tick);
                k->SetEnable(dev, k, CLKENAB_INDEX);

                DEBUG
                    ("s626_ai_cmd: convert trigger timer is set with value %d\n",
                     tick);
                break;
        case TRIG_EXT:
                /*  set the digital line and interrupt for convert trigger */
                if (cmd->scan_begin_src != TRIG_EXT
                    && cmd->start_src == TRIG_EXT)
                        s626_dio_set_irq(dev, cmd->convert_arg);

                DEBUG("s626_ai_cmd: External convert trigger is set!!!\n");

                break;
        }

        switch (cmd->stop_src) {
        case TRIG_COUNT:
                /*  data arrives as one packet */
                devpriv->ai_sample_count = cmd->stop_arg;
                devpriv->ai_continous = 0;
                break;
        case TRIG_NONE:
                /*  continous aquisition */
                devpriv->ai_continous = 1;
                devpriv->ai_sample_count = 0;
                break;
        }

        ResetADC(dev, ppl);

        switch (cmd->start_src) {
        case TRIG_NOW:
                /*  Trigger ADC scan loop start by setting RPS Signal 0. */
                /*  MC_ENABLE( P_MC2, MC2_ADC_RPS ); */

                /*  Start executing the RPS program. */
                MC_ENABLE(P_MC1, MC1_ERPS1);

                DEBUG("s626_ai_cmd: ADC triggered\n");
                s->async->inttrig = NULL;
                break;
        case TRIG_EXT:
                /* configure DIO channel for acquisition trigger */
                s626_dio_set_irq(dev, cmd->start_arg);

                DEBUG("s626_ai_cmd: External start trigger is set!!!\n");

                s->async->inttrig = NULL;
                break;
        case TRIG_INT:
                s->async->inttrig = s626_ai_inttrig;
                break;
        }

        /* enable interrupt */
        writel(IRQ_GPIO3 | IRQ_RPS1, devpriv->base_addr + P_IER);

        DEBUG("s626_ai_cmd: command function terminated\n");

        return 0;
}

static int s626_ai_cmdtest(struct comedi_device *dev,
                           struct comedi_subdevice *s, struct comedi_cmd *cmd)
{
        int err = 0;
        int tmp;

        /* cmdtest tests a particular command to see if it is valid.  Using
         * the cmdtest ioctl, a user can create a valid cmd and then have it
         * executes by the cmd ioctl.
         *
         * cmdtest returns 1,2,3,4 or 0, depending on which tests the
         * command passes. */

        /* step 1: make sure trigger sources are trivially valid */

        tmp = cmd->start_src;
        cmd->start_src &= TRIG_NOW | TRIG_INT | TRIG_EXT;
        if (!cmd->start_src || tmp != cmd->start_src)
                err++;

        tmp = cmd->scan_begin_src;
        cmd->scan_begin_src &= TRIG_TIMER | TRIG_EXT | TRIG_FOLLOW;
        if (!cmd->scan_begin_src || tmp != cmd->scan_begin_src)
                err++;

        tmp = cmd->convert_src;
        cmd->convert_src &= TRIG_TIMER | TRIG_EXT | TRIG_NOW;
        if (!cmd->convert_src || tmp != cmd->convert_src)
                err++;

        tmp = cmd->scan_end_src;
        cmd->scan_end_src &= TRIG_COUNT;
        if (!cmd->scan_end_src || tmp != cmd->scan_end_src)
                err++;

        tmp = cmd->stop_src;
        cmd->stop_src &= TRIG_COUNT | TRIG_NONE;
        if (!cmd->stop_src || tmp != cmd->stop_src)
                err++;

        if (err)
                return 1;

        /* step 2: make sure trigger sources are unique and mutually
           compatible */

        /* note that mutual compatiblity is not an issue here */
        if (cmd->scan_begin_src != TRIG_TIMER &&
            cmd->scan_begin_src != TRIG_EXT
            && cmd->scan_begin_src != TRIG_FOLLOW)
                err++;
        if (cmd->convert_src != TRIG_TIMER &&
            cmd->convert_src != TRIG_EXT && cmd->convert_src != TRIG_NOW)
                err++;
        if (cmd->stop_src != TRIG_COUNT && cmd->stop_src != TRIG_NONE)
                err++;

        if (err)
                return 2;

        /* step 3: make sure arguments are trivially compatible */

        if (cmd->start_src != TRIG_EXT && cmd->start_arg != 0) {
                cmd->start_arg = 0;
                err++;
        }

        if (cmd->start_src == TRIG_EXT && cmd->start_arg > 39) {
                cmd->start_arg = 39;
                err++;
        }

        if (cmd->scan_begin_src == TRIG_EXT && cmd->scan_begin_arg > 39) {
                cmd->scan_begin_arg = 39;
                err++;
        }

        if (cmd->convert_src == TRIG_EXT && cmd->convert_arg > 39) {
                cmd->convert_arg = 39;
                err++;
        }
#define MAX_SPEED       200000  /* in nanoseconds */
#define MIN_SPEED       2000000000      /* in nanoseconds */

        if (cmd->scan_begin_src == TRIG_TIMER) {
                if (cmd->scan_begin_arg < MAX_SPEED) {
                        cmd->scan_begin_arg = MAX_SPEED;
                        err++;
                }
                if (cmd->scan_begin_arg > MIN_SPEED) {
                        cmd->scan_begin_arg = MIN_SPEED;
                        err++;
                }
        } else {
                /* external trigger */
                /* should be level/edge, hi/lo specification here */
                /* should specify multiple external triggers */
/*     if(cmd->scan_begin_arg>9){ */
/*       cmd->scan_begin_arg=9; */
/*       err++; */
/*     } */
        }
        if (cmd->convert_src == TRIG_TIMER) {
                if (cmd->convert_arg < MAX_SPEED) {
                        cmd->convert_arg = MAX_SPEED;
                        err++;
                }
                if (cmd->convert_arg > MIN_SPEED) {
                        cmd->convert_arg = MIN_SPEED;
                        err++;
                }
        } else {
                /* external trigger */
                /* see above */
/*     if(cmd->convert_arg>9){ */
/*       cmd->convert_arg=9; */
/*       err++; */
/*     } */

        }

        if (cmd->scan_end_arg != cmd->chanlist_len) {
                cmd->scan_end_arg = cmd->chanlist_len;
                err++;
        }
        if (cmd->stop_src == TRIG_COUNT) {
                if (cmd->stop_arg > 0x00ffffff) {
                        cmd->stop_arg = 0x00ffffff;
                        err++;
                }
        } else {
                /* TRIG_NONE */
                if (cmd->stop_arg != 0) {
                        cmd->stop_arg = 0;
                        err++;
                }
        }

        if (err)
                return 3;

        /* step 4: fix up any arguments */

        if (cmd->scan_begin_src == TRIG_TIMER) {
                tmp = cmd->scan_begin_arg;
                s626_ns_to_timer((int *)&cmd->scan_begin_arg,
                                 cmd->flags & TRIG_ROUND_MASK);
                if (tmp != cmd->scan_begin_arg)
                        err++;
        }
        if (cmd->convert_src == TRIG_TIMER) {
                tmp = cmd->convert_arg;
                s626_ns_to_timer((int *)&cmd->convert_arg,
                                 cmd->flags & TRIG_ROUND_MASK);
                if (tmp != cmd->convert_arg)
                        err++;
                if (cmd->scan_begin_src == TRIG_TIMER &&
                    cmd->scan_begin_arg <
                    cmd->convert_arg * cmd->scan_end_arg) {
                        cmd->scan_begin_arg =
                            cmd->convert_arg * cmd->scan_end_arg;
                        err++;
                }
        }

        if (err)
                return 4;

        return 0;
}

static int s626_ai_cancel(struct comedi_device *dev, struct comedi_subdevice *s)
{
        /*  Stop RPS program in case it is currently running. */
        MC_DISABLE(P_MC1, MC1_ERPS1);

        /* disable master interrupt */
        writel(0, devpriv->base_addr + P_IER);

        devpriv->ai_cmd_running = 0;

        return 0;
}

/* This function doesn't require a particular form, this is just what
 * happens to be used in some of the drivers.  It should convert ns
 * nanoseconds to a counter value suitable for programming the device.
 * Also, it should adjust ns so that it cooresponds to the actual time
 * that the device will use. */
static int s626_ns_to_timer(int *nanosec, int round_mode)
{
        int divider, base;

        base = 500;             /* 2MHz internal clock */

        switch (round_mode) {
        case TRIG_ROUND_NEAREST:
        default:
                divider = (*nanosec + base / 2) / base;
                break;
        case TRIG_ROUND_DOWN:
                divider = (*nanosec) / base;
                break;
        case TRIG_ROUND_UP:
                divider = (*nanosec + base - 1) / base;
                break;
        }

        *nanosec = base * divider;
        return divider - 1;
}

static int s626_ao_winsn(struct comedi_device *dev, struct comedi_subdevice *s,
                         struct comedi_insn *insn, unsigned int *data)
{

        int i;
        uint16_t chan = CR_CHAN(insn->chanspec);
        int16_t dacdata;

        for (i = 0; i < insn->n; i++) {
                dacdata = (int16_t) data[i];
                devpriv->ao_readback[CR_CHAN(insn->chanspec)] = data[i];
                dacdata -= (0x1fff);

                SetDAC(dev, chan, dacdata);
        }

        return i;
}

static int s626_ao_rinsn(struct comedi_device *dev, struct comedi_subdevice *s,
                         struct comedi_insn *insn, unsigned int *data)
{
        int i;

        for (i = 0; i < insn->n; i++)
                data[i] = devpriv->ao_readback[CR_CHAN(insn->chanspec)];

        return i;
}

/* *************** DIGITAL I/O FUNCTIONS ***************
 * All DIO functions address a group of DIO channels by means of
 * "group" argument.  group may be 0, 1 or 2, which correspond to DIO
 * ports A, B and C, respectively.
 */

static void s626_dio_init(struct comedi_device *dev)
{
        uint16_t group;
        struct comedi_subdevice *s;

        /*  Prepare to treat writes to WRCapSel as capture disables. */
        DEBIwrite(dev, LP_MISC1, MISC1_NOEDCAP);

        /*  For each group of sixteen channels ... */
        for (group = 0; group < S626_DIO_BANKS; group++) {
                s = dev->subdevices + 2 + group;
                DEBIwrite(dev, diopriv->WRIntSel, 0);   /*  Disable all interrupts. */
                DEBIwrite(dev, diopriv->WRCapSel, 0xFFFF);      /*  Disable all event */
                /*  captures. */
                DEBIwrite(dev, diopriv->WREdgSel, 0);   /*  Init all DIOs to */
                /*  default edge */
                /*  polarity. */
                DEBIwrite(dev, diopriv->WRDOut, 0);     /*  Program all outputs */
                /*  to inactive state. */
        }
        DEBUG("s626_dio_init: DIO initialized \n");
}

/* DIO devices are slightly special.  Although it is possible to
 * implement the insn_read/insn_write interface, it is much more
 * useful to applications if you implement the insn_bits interface.
 * This allows packed reading/writing of the DIO channels.  The comedi
 * core can convert between insn_bits and insn_read/write */

static int s626_dio_insn_bits(struct comedi_device *dev,
                              struct comedi_subdevice *s,
                              struct comedi_insn *insn, unsigned int *data)
{

        /* Length of data must be 2 (mask and new data, see below) */
        if (insn->n == 0)
                return 0;

        if (insn->n != 2) {
                printk
                    ("comedi%d: s626: s626_dio_insn_bits(): Invalid instruction length\n",
                     dev->minor);
                return -EINVAL;
        }

        /*
         * The insn data consists of a mask in data[0] and the new data in
         * data[1]. The mask defines which bits we are concerning about.
         * The new data must be anded with the mask.  Each channel
         * corresponds to a bit.
         */
        if (data[0]) {
                /* Check if requested ports are configured for output */
                if ((s->io_bits & data[0]) != data[0])
                        return -EIO;

                s->state &= ~data[0];
                s->state |= data[0] & data[1];

                /* Write out the new digital output lines */

                DEBIwrite(dev, diopriv->WRDOut, s->state);
        }
        data[1] = DEBIread(dev, diopriv->RDDIn);

        return 2;
}

static int s626_dio_insn_config(struct comedi_device *dev,
                                struct comedi_subdevice *s,
                                struct comedi_insn *insn, unsigned int *data)
{

        switch (data[0]) {
        case INSN_CONFIG_DIO_QUERY:
                data[1] =
                    (s->
                     io_bits & (1 << CR_CHAN(insn->chanspec))) ? COMEDI_OUTPUT :
                    COMEDI_INPUT;
                return insn->n;
                break;
        case COMEDI_INPUT:
                s->io_bits &= ~(1 << CR_CHAN(insn->chanspec));
                break;
        case COMEDI_OUTPUT:
                s->io_bits |= 1 << CR_CHAN(insn->chanspec);
                break;
        default:
                return -EINVAL;
                break;
        }
        DEBIwrite(dev, diopriv->WRDOut, s->io_bits);

        return 1;
}

static int s626_dio_set_irq(struct comedi_device *dev, unsigned int chan)
{
        unsigned int group;
        unsigned int bitmask;
        unsigned int status;

        /* select dio bank */
        group = chan / 16;
        bitmask = 1 << (chan - (16 * group));
        DEBUG("s626_dio_set_irq: enable interrupt on dio channel %d group %d\n",
              chan - (16 * group), group);

        /* set channel to capture positive edge */
        status = DEBIread(dev,
                          ((struct dio_private *)(dev->subdevices + 2 +
                                                  group)->private)->RDEdgSel);
        DEBIwrite(dev,
                  ((struct dio_private *)(dev->subdevices + 2 +
                                          group)->private)->WREdgSel,
                  bitmask | status);

        /* enable interrupt on selected channel */
        status = DEBIread(dev,
                          ((struct dio_private *)(dev->subdevices + 2 +
                                                  group)->private)->RDIntSel);
        DEBIwrite(dev,
                  ((struct dio_private *)(dev->subdevices + 2 +
                                          group)->private)->WRIntSel,
                  bitmask | status);

        /* enable edge capture write command */
        DEBIwrite(dev, LP_MISC1, MISC1_EDCAP);

        /* enable edge capture on selected channel */
        status = DEBIread(dev,
                          ((struct dio_private *)(dev->subdevices + 2 +
                                                  group)->private)->RDCapSel);
        DEBIwrite(dev,
                  ((struct dio_private *)(dev->subdevices + 2 +
                                          group)->private)->WRCapSel,
                  bitmask | status);

        return 0;
}

static int s626_dio_reset_irq(struct comedi_device *dev, unsigned int group,
                              unsigned int mask)
{
        DEBUG
            ("s626_dio_reset_irq: disable  interrupt on dio channel %d group %d\n",
             mask, group);

        /* disable edge capture write command */
        DEBIwrite(dev, LP_MISC1, MISC1_NOEDCAP);

        /* enable edge capture on selected channel */
        DEBIwrite(dev,
                  ((struct dio_private *)(dev->subdevices + 2 +
                                          group)->private)->WRCapSel, mask);

        return 0;
}

static int s626_dio_clear_irq(struct comedi_device *dev)
{
        unsigned int group;

        /* disable edge capture write command */
        DEBIwrite(dev, LP_MISC1, MISC1_NOEDCAP);

        for (group = 0; group < S626_DIO_BANKS; group++) {
                /* clear pending events and interrupt */
                DEBIwrite(dev,
                          ((struct dio_private *)(dev->subdevices + 2 +
                                                  group)->private)->WRCapSel,
                          0xffff);
        }

        return 0;
}

/* Now this function initializes the value of the counter (data[0])
   and set the subdevice. To complete with trigger and interrupt
   configuration */
static int s626_enc_insn_config(struct comedi_device *dev,
                                struct comedi_subdevice *s,
                                struct comedi_insn *insn, unsigned int *data)
{
        uint16_t Setup = (LOADSRC_INDX << BF_LOADSRC) | /*  Preload upon */
            /*  index. */
            (INDXSRC_SOFT << BF_INDXSRC) |      /*  Disable hardware index. */
            (CLKSRC_COUNTER << BF_CLKSRC) |     /*  Operating mode is Counter. */
            (CLKPOL_POS << BF_CLKPOL) | /*  Active high clock. */
            /* ( CNTDIR_UP << BF_CLKPOL ) |      // Count direction is Down. */
            (CLKMULT_1X << BF_CLKMULT) |        /*  Clock multiplier is 1x. */
            (CLKENAB_INDEX << BF_CLKENAB);
        /*   uint16_t DisableIntSrc=TRUE; */
        /*  uint32_t Preloadvalue;              //Counter initial value */
        uint16_t valueSrclatch = LATCHSRC_AB_READ;
        uint16_t enab = CLKENAB_ALWAYS;
        struct enc_private *k = &encpriv[CR_CHAN(insn->chanspec)];

        DEBUG("s626_enc_insn_config: encoder config\n");

        /*   (data==NULL) ? (Preloadvalue=0) : (Preloadvalue=data[0]); */

        k->SetMode(dev, k, Setup, TRUE);
        Preload(dev, k, *(insn->data));
        k->PulseIndex(dev, k);
        SetLatchSource(dev, k, valueSrclatch);
        k->SetEnable(dev, k, (uint16_t) (enab != 0));

        return insn->n;
}

static int s626_enc_insn_read(struct comedi_device *dev,
                              struct comedi_subdevice *s,
                              struct comedi_insn *insn, unsigned int *data)
{

        int n;
        struct enc_private *k = &encpriv[CR_CHAN(insn->chanspec)];

        DEBUG("s626_enc_insn_read: encoder read channel %d \n",
              CR_CHAN(insn->chanspec));

        for (n = 0; n < insn->n; n++)
                data[n] = ReadLatch(dev, k);

        DEBUG("s626_enc_insn_read: encoder sample %d\n", data[n]);

        return n;
}

static int s626_enc_insn_write(struct comedi_device *dev,
                               struct comedi_subdevice *s,
                               struct comedi_insn *insn, unsigned int *data)
{

        struct enc_private *k = &encpriv[CR_CHAN(insn->chanspec)];

        DEBUG("s626_enc_insn_write: encoder write channel %d \n",
              CR_CHAN(insn->chanspec));

        /*  Set the preload register */
        Preload(dev, k, data[0]);

        /*  Software index pulse forces the preload register to load */
        /*  into the counter */
        k->SetLoadTrig(dev, k, 0);
        k->PulseIndex(dev, k);
        k->SetLoadTrig(dev, k, 2);

        DEBUG("s626_enc_insn_write: End encoder write\n");

        return 1;
}

static void s626_timer_load(struct comedi_device *dev, struct enc_private *k,
                            int tick)
{
        uint16_t Setup = (LOADSRC_INDX << BF_LOADSRC) | /*  Preload upon */
            /*  index. */
            (INDXSRC_SOFT << BF_INDXSRC) |      /*  Disable hardware index. */
            (CLKSRC_TIMER << BF_CLKSRC) |       /*  Operating mode is Timer. */
            (CLKPOL_POS << BF_CLKPOL) | /*  Active high clock. */
            (CNTDIR_DOWN << BF_CLKPOL) |        /*  Count direction is Down. */
            (CLKMULT_1X << BF_CLKMULT) |        /*  Clock multiplier is 1x. */
            (CLKENAB_INDEX << BF_CLKENAB);
        uint16_t valueSrclatch = LATCHSRC_A_INDXA;
        /*   uint16_t enab=CLKENAB_ALWAYS; */

        k->SetMode(dev, k, Setup, FALSE);

        /*  Set the preload register */
        Preload(dev, k, tick);

        /*  Software index pulse forces the preload register to load */
        /*  into the counter */
        k->SetLoadTrig(dev, k, 0);
        k->PulseIndex(dev, k);

        /* set reload on counter overflow */
        k->SetLoadTrig(dev, k, 1);

        /* set interrupt on overflow */
        k->SetIntSrc(dev, k, INTSRC_OVER);

        SetLatchSource(dev, k, valueSrclatch);
        /*   k->SetEnable(dev,k,(uint16_t)(enab != 0)); */
}

/* ***********  DAC FUNCTIONS *********** */

/*  Slot 0 base settings. */
#define VECT0   (XSD2 | RSD3 | SIB_A2)
/*  Slot 0 always shifts in  0xFF and store it to  FB_BUFFER2. */

/*  TrimDac LogicalChan-to-PhysicalChan mapping table. */
static uint8_t trimchan[] = { 10, 9, 8, 3, 2, 7, 6, 1, 0, 5, 4 };

/*  TrimDac LogicalChan-to-EepromAdrs mapping table. */
static uint8_t trimadrs[] =
    { 0x40, 0x41, 0x42, 0x50, 0x51, 0x52, 0x53, 0x60, 0x61, 0x62, 0x63 };

static void LoadTrimDACs(struct comedi_device *dev)
{
        register uint8_t i;

        /*  Copy TrimDac setpoint values from EEPROM to TrimDacs. */
        for (i = 0; i < ARRAY_SIZE(trimchan); i++)
                WriteTrimDAC(dev, i, I2Cread(dev, trimadrs[i]));
}

static void WriteTrimDAC(struct comedi_device *dev, uint8_t LogicalChan,
                         uint8_t DacData)
{
        uint32_t chan;

        /*  Save the new setpoint in case the application needs to read it back later. */
        devpriv->TrimSetpoint[LogicalChan] = (uint8_t) DacData;

        /*  Map logical channel number to physical channel number. */
        chan = (uint32_t) trimchan[LogicalChan];

        /* Set up TSL2 records for TrimDac write operation.  All slots shift
         * 0xFF in from pulled-up SD3 so that the end of the slot sequence
         * can be detected.
         */

        SETVECT(2, XSD2 | XFIFO_1 | WS3);
        /* Slot 2: Send high uint8_t to target TrimDac. */
        SETVECT(3, XSD2 | XFIFO_0 | WS3);
        /* Slot 3: Send low uint8_t to target TrimDac. */
        SETVECT(4, XSD2 | XFIFO_3 | WS1);
        /* Slot 4: Send NOP high uint8_t to DAC0 to keep clock running. */
        SETVECT(5, XSD2 | XFIFO_2 | WS1 | EOS);
        /* Slot 5: Send NOP low  uint8_t to DAC0. */

        /* Construct and transmit target DAC's serial packet:
         * ( 0000 AAAA ), ( DDDD DDDD ),( 0x00 ),( 0x00 ) where A<3:0> is the
         * DAC channel's address, and D<7:0> is the DAC setpoint.  Append a
         * WORD value (that writes a channel 0 NOP command to a non-existent
         * main DAC channel) that serves to keep the clock running after the
         * packet has been sent to the target DAC.
         */

        /*  Address the DAC channel within the trimdac device. */
        SendDAC(dev, ((uint32_t) chan << 8)
                | (uint32_t) DacData);  /*  Include DAC setpoint data. */
}

/* **************  EEPROM ACCESS FUNCTIONS  ************** */
/*  Read uint8_t from EEPROM. */

static uint8_t I2Cread(struct comedi_device *dev, uint8_t addr)
{
        uint8_t rtnval;

        /*  Send EEPROM target address. */
        if (I2Chandshake(dev, I2C_B2(I2C_ATTRSTART, I2CW)
                         /* Byte2 = I2C command: write to I2C EEPROM  device. */
                         | I2C_B1(I2C_ATTRSTOP, addr)
                         /* Byte1 = EEPROM internal target address. */
                         | I2C_B0(I2C_ATTRNOP, 0))) {   /*  Byte0 = Not sent. */
                /*  Abort function and declare error if handshake failed. */
                DEBUG("I2Cread: error handshake I2Cread  a\n");
                return 0;
        }
        /*  Execute EEPROM read. */
        if (I2Chandshake(dev, I2C_B2(I2C_ATTRSTART, I2CR)

                         /*  Byte2 = I2C */
                         /*  command: read */
                         /*  from I2C EEPROM */
                         /*  device. */
                         |I2C_B1(I2C_ATTRSTOP, 0)

                         /*  Byte1 receives */
                         /*  uint8_t from */
                         /*  EEPROM. */
                         |I2C_B0(I2C_ATTRNOP, 0))) {    /*  Byte0 = Not  sent. */

                /*  Abort function and declare error if handshake failed. */
                DEBUG("I2Cread: error handshake I2Cread b\n");
                return 0;
        }
        /*  Return copy of EEPROM value. */
        rtnval = (uint8_t) (RR7146(P_I2CCTRL) >> 16);
        return rtnval;
}

static uint32_t I2Chandshake(struct comedi_device *dev, uint32_t val)
{
        /*  Write I2C command to I2C Transfer Control shadow register. */
        WR7146(P_I2CCTRL, val);

        /*  Upload I2C shadow registers into working registers and wait for */
        /*  upload confirmation. */

        MC_ENABLE(P_MC2, MC2_UPLD_IIC);
        while (!MC_TEST(P_MC2, MC2_UPLD_IIC)) ;

        /*  Wait until I2C bus transfer is finished or an error occurs. */
        while ((RR7146(P_I2CCTRL) & (I2C_BUSY | I2C_ERR)) == I2C_BUSY) ;

        /*  Return non-zero if I2C error occured. */
        return RR7146(P_I2CCTRL) & I2C_ERR;

}

/*  Private helper function: Write setpoint to an application DAC channel. */

static void SetDAC(struct comedi_device *dev, uint16_t chan, short dacdata)
{
        register uint16_t signmask;
        register uint32_t WSImage;

        /*  Adjust DAC data polarity and set up Polarity Control Register */
        /*  image. */
        signmask = 1 << chan;
        if (dacdata < 0) {
                dacdata = -dacdata;
                devpriv->Dacpol |= signmask;
        } else
                devpriv->Dacpol &= ~signmask;

        /*  Limit DAC setpoint value to valid range. */
        if ((uint16_t) dacdata > 0x1FFF)
                dacdata = 0x1FFF;

        /* Set up TSL2 records (aka "vectors") for DAC update.  Vectors V2
         * and V3 transmit the setpoint to the target DAC.  V4 and V5 send
         * data to a non-existent TrimDac channel just to keep the clock
         * running after sending data to the target DAC.  This is necessary
         * to eliminate the clock glitch that would otherwise occur at the
         * end of the target DAC's serial data stream.  When the sequence
         * restarts at V0 (after executing V5), the gate array automatically
         * disables gating for the DAC clock and all DAC chip selects.
         */

        WSImage = (chan & 2) ? WS1 : WS2;
        /* Choose DAC chip select to be asserted. */
        SETVECT(2, XSD2 | XFIFO_1 | WSImage);
        /* Slot 2: Transmit high data byte to target DAC. */
        SETVECT(3, XSD2 | XFIFO_0 | WSImage);
        /* Slot 3: Transmit low data byte to target DAC. */
        SETVECT(4, XSD2 | XFIFO_3 | WS3);
        /* Slot 4: Transmit to non-existent TrimDac channel to keep clock */
        SETVECT(5, XSD2 | XFIFO_2 | WS3 | EOS);
        /* Slot 5: running after writing target DAC's low data byte. */

        /*  Construct and transmit target DAC's serial packet:
         * ( A10D DDDD ),( DDDD DDDD ),( 0x0F ),( 0x00 ) where A is chan<0>,
         * and D<12:0> is the DAC setpoint.  Append a WORD value (that writes
         * to a  non-existent TrimDac channel) that serves to keep the clock
         * running after the packet has been sent to the target DAC.
         */
        SendDAC(dev, 0x0F000000
                /* Continue clock after target DAC data (write to non-existent trimdac). */
                | 0x00004000
                /* Address the two main dual-DAC devices (TSL's chip select enables
                 * target device). */
                | ((uint32_t) (chan & 1) << 15)
                /*  Address the DAC channel within the  device. */
                | (uint32_t) dacdata);  /*  Include DAC setpoint data. */

}

/* Private helper function: Transmit serial data to DAC via Audio
 * channel 2.  Assumes: (1) TSL2 slot records initialized, and (2)
 * Dacpol contains valid target image.
 */

static void SendDAC(struct comedi_device *dev, uint32_t val)
{

        /* START THE SERIAL CLOCK RUNNING ------------- */

        /* Assert DAC polarity control and enable gating of DAC serial clock
         * and audio bit stream signals.  At this point in time we must be
         * assured of being in time slot 0.  If we are not in slot 0, the
         * serial clock and audio stream signals will be disabled; this is
         * because the following DEBIwrite statement (which enables signals
         * to be passed through the gate array) would execute before the
         * trailing edge of WS1/WS3 (which turns off the signals), thus
         * causing the signals to be inactive during the DAC write.
         */
        DEBIwrite(dev, LP_DACPOL, devpriv->Dacpol);

        /* TRANSFER OUTPUT DWORD VALUE INTO A2'S OUTPUT FIFO ---------------- */

        /* Copy DAC setpoint value to DAC's output DMA buffer. */

        /* WR7146( (uint32_t)devpriv->pDacWBuf, val ); */
        *devpriv->pDacWBuf = val;

        /* enab the output DMA transfer.  This will cause the DMAC to copy
         * the DAC's data value to A2's output FIFO.  The DMA transfer will
         * then immediately terminate because the protection address is
         * reached upon transfer of the first DWORD value.
         */
        MC_ENABLE(P_MC1, MC1_A2OUT);

        /*  While the DMA transfer is executing ... */

        /* Reset Audio2 output FIFO's underflow flag (along with any other
         * FIFO underflow/overflow flags).  When set, this flag will
         * indicate that we have emerged from slot 0.
         */
        WR7146(P_ISR, ISR_AFOU);

        /* Wait for the DMA transfer to finish so that there will be data
         * available in the FIFO when time slot 1 tries to transfer a DWORD
         * from the FIFO to the output buffer register.  We test for DMA
         * Done by polling the DMAC enable flag; this flag is automatically
         * cleared when the transfer has finished.
         */
        while ((RR7146(P_MC1) & MC1_A2OUT) != 0) ;

        /* START THE OUTPUT STREAM TO THE TARGET DAC -------------------- */

        /* FIFO data is now available, so we enable execution of time slots
         * 1 and higher by clearing the EOS flag in slot 0.  Note that SD3
         * will be shifted in and stored in FB_BUFFER2 for end-of-slot-list
         * detection.
         */
        SETVECT(0, XSD2 | RSD3 | SIB_A2);

        /* Wait for slot 1 to execute to ensure that the Packet will be
         * transmitted.  This is detected by polling the Audio2 output FIFO
         * underflow flag, which will be set when slot 1 execution has
         * finished transferring the DAC's data DWORD from the output FIFO
         * to the output buffer register.
         */
        while ((RR7146(P_SSR) & SSR_AF2_OUT) == 0) ;

        /* Set up to trap execution at slot 0 when the TSL sequencer cycles
         * back to slot 0 after executing the EOS in slot 5.  Also,
         * simultaneously shift out and in the 0x00 that is ALWAYS the value
         * stored in the last byte to be shifted out of the FIFO's DWORD
         * buffer register.
         */
        SETVECT(0, XSD2 | XFIFO_2 | RSD2 | SIB_A2 | EOS);

        /* WAIT FOR THE TRANSACTION TO FINISH ----------------------- */

        /* Wait for the TSL to finish executing all time slots before
         * exiting this function.  We must do this so that the next DAC
         * write doesn't start, thereby enabling clock/chip select signals:
         *
         * 1. Before the TSL sequence cycles back to slot 0, which disables
         *    the clock/cs signal gating and traps slot // list execution.
         *    we have not yet finished slot 5 then the clock/cs signals are
         *    still gated and we have not finished transmitting the stream.
         *
         * 2. While slots 2-5 are executing due to a late slot 0 trap.  In
         *    this case, the slot sequence is currently repeating, but with
         *    clock/cs signals disabled.  We must wait for slot 0 to trap
         *    execution before setting up the next DAC setpoint DMA transfer
         *    and enabling the clock/cs signals.  To detect the end of slot 5,
         *    we test for the FB_BUFFER2 MSB contents to be equal to 0xFF.  If
         *    the TSL has not yet finished executing slot 5 ...
         */
        if ((RR7146(P_FB_BUFFER2) & 0xFF000000) != 0) {
                /* The trap was set on time and we are still executing somewhere
                 * in slots 2-5, so we now wait for slot 0 to execute and trap
                 * TSL execution.  This is detected when FB_BUFFER2 MSB changes
                 * from 0xFF to 0x00, which slot 0 causes to happen by shifting
                 * out/in on SD2 the 0x00 that is always referenced by slot 5.
                 */
                while ((RR7146(P_FB_BUFFER2) & 0xFF000000) != 0) ;
        }
        /* Either (1) we were too late setting the slot 0 trap; the TSL
         * sequencer restarted slot 0 before we could set the EOS trap flag,
         * or (2) we were not late and execution is now trapped at slot 0.
         * In either case, we must now change slot 0 so that it will store
         * value 0xFF (instead of 0x00) to FB_BUFFER2 next time it executes.
         * In order to do this, we reprogram slot 0 so that it will shift in
         * SD3, which is driven only by a pull-up resistor.
         */
        SETVECT(0, RSD3 | SIB_A2 | EOS);

        /* Wait for slot 0 to execute, at which time the TSL is setup for
         * the next DAC write.  This is detected when FB_BUFFER2 MSB changes
         * from 0x00 to 0xFF.
         */
        while ((RR7146(P_FB_BUFFER2) & 0xFF000000) == 0) ;
}

static void WriteMISC2(struct comedi_device *dev, uint16_t NewImage)
{
        DEBIwrite(dev, LP_MISC1, MISC1_WENABLE);        /*  enab writes to */
        /*  MISC2 register. */
        DEBIwrite(dev, LP_WRMISC2, NewImage);   /*  Write new image to MISC2. */
        DEBIwrite(dev, LP_MISC1, MISC1_WDISABLE);       /*  Disable writes to MISC2. */
}

/*  Initialize the DEBI interface for all transfers. */

static uint16_t DEBIread(struct comedi_device *dev, uint16_t addr)
{
        uint16_t retval;

        /*  Set up DEBI control register value in shadow RAM. */
        WR7146(P_DEBICMD, DEBI_CMD_RDWORD | addr);

        /*  Execute the DEBI transfer. */
        DEBItransfer(dev);

        /*  Fetch target register value. */
        retval = (uint16_t) RR7146(P_DEBIAD);

        /*  Return register value. */
        return retval;
}

/*  Execute a DEBI transfer.  This must be called from within a */
/*  critical section. */
static void DEBItransfer(struct comedi_device *dev)
{
        /*  Initiate upload of shadow RAM to DEBI control register. */
        MC_ENABLE(P_MC2, MC2_UPLD_DEBI);

        /*  Wait for completion of upload from shadow RAM to DEBI control */
        /*  register. */
        while (!MC_TEST(P_MC2, MC2_UPLD_DEBI)) ;

        /*  Wait until DEBI transfer is done. */
        while (RR7146(P_PSR) & PSR_DEBI_S) ;
}

/*  Write a value to a gate array register. */
static void DEBIwrite(struct comedi_device *dev, uint16_t addr, uint16_t wdata)
{

        /*  Set up DEBI control register value in shadow RAM. */
        WR7146(P_DEBICMD, DEBI_CMD_WRWORD | addr);
        WR7146(P_DEBIAD, wdata);

        /*  Execute the DEBI transfer. */
        DEBItransfer(dev);
}

/* Replace the specified bits in a gate array register.  Imports: mask
 * specifies bits that are to be preserved, wdata is new value to be
 * or'd with the masked original.
 */
static void DEBIreplace(struct comedi_device *dev, uint16_t addr, uint16_t mask,
                        uint16_t wdata)
{

        /*  Copy target gate array register into P_DEBIAD register. */
        WR7146(P_DEBICMD, DEBI_CMD_RDWORD | addr);
        /* Set up DEBI control reg value in shadow RAM. */
        DEBItransfer(dev);      /*  Execute the DEBI Read transfer. */

        /*  Write back the modified image. */
        WR7146(P_DEBICMD, DEBI_CMD_WRWORD | addr);
        /* Set up DEBI control reg value in shadow  RAM. */

        WR7146(P_DEBIAD, wdata | ((uint16_t) RR7146(P_DEBIAD) & mask));
        /* Modify the register image. */
        DEBItransfer(dev);      /*  Execute the DEBI Write transfer. */
}

static void CloseDMAB(struct comedi_device *dev, struct bufferDMA *pdma,
                      size_t bsize)
{
        void *vbptr;
        dma_addr_t vpptr;

        DEBUG("CloseDMAB: Entering S626DRV_CloseDMAB():\n");
        if (pdma == NULL)
                return;
        /* find the matching allocation from the board struct */

        vbptr = pdma->LogicalBase;
        vpptr = pdma->PhysicalBase;
        if (vbptr) {
                pci_free_consistent(devpriv->pdev, bsize, vbptr, vpptr);
                pdma->LogicalBase = 0;
                pdma->PhysicalBase = 0;

                DEBUG("CloseDMAB(): Logical=%p, bsize=%d, Physical=0x%x\n",
                      vbptr, bsize, (uint32_t) vpptr);
        }
}

/* ******  COUNTER FUNCTIONS  ******* */
/* All counter functions address a specific counter by means of the
 * "Counter" argument, which is a logical counter number.  The Counter
 * argument may have any of the following legal values: 0=0A, 1=1A,
 * 2=2A, 3=0B, 4=1B, 5=2B.
 */

/* Forward declarations for functions that are common to both A and B counters: */

/* ******  PRIVATE COUNTER FUNCTIONS ****** */

/*  Read a counter's output latch. */

static uint32_t ReadLatch(struct comedi_device *dev, struct enc_private *k)
{
        register uint32_t value;
        /* DEBUG FIXME DEBUG("ReadLatch: Read Latch enter\n"); */

        /*  Latch counts and fetch LSW of latched counts value. */
        value = (uint32_t) DEBIread(dev, k->MyLatchLsw);

        /*  Fetch MSW of latched counts and combine with LSW. */
        value |= ((uint32_t) DEBIread(dev, k->MyLatchLsw + 2) << 16);

        /*  DEBUG FIXME DEBUG("ReadLatch: Read Latch exit\n"); */

        /*  Return latched counts. */
        return value;
}

/*  Reset a counter's index and overflow event capture flags. */

static void ResetCapFlags_A(struct comedi_device *dev, struct enc_private *k)
{
        DEBIreplace(dev, k->MyCRB, (uint16_t) (~CRBMSK_INTCTRL),
                    CRBMSK_INTRESETCMD | CRBMSK_INTRESET_A);
}

static void ResetCapFlags_B(struct comedi_device *dev, struct enc_private *k)
{
        DEBIreplace(dev, k->MyCRB, (uint16_t) (~CRBMSK_INTCTRL),
                    CRBMSK_INTRESETCMD | CRBMSK_INTRESET_B);
}

/*  Return counter setup in a format (COUNTER_SETUP) that is consistent */
/*  for both A and B counters. */

static uint16_t GetMode_A(struct comedi_device *dev, struct enc_private *k)
{
        register uint16_t cra;
        register uint16_t crb;
        register uint16_t setup;

        /*  Fetch CRA and CRB register images. */
        cra = DEBIread(dev, k->MyCRA);
        crb = DEBIread(dev, k->MyCRB);

        /*  Populate the standardized counter setup bit fields.  Note: */
        /*  IndexSrc is restricted to ENC_X or IndxPol. */
        setup = ((cra & STDMSK_LOADSRC) /*  LoadSrc  = LoadSrcA. */
                 |((crb << (STDBIT_LATCHSRC - CRBBIT_LATCHSRC)) & STDMSK_LATCHSRC)      /*  LatchSrc = LatchSrcA. */
                 |((cra << (STDBIT_INTSRC - CRABIT_INTSRC_A)) & STDMSK_INTSRC)  /*  IntSrc   = IntSrcA. */
                 |((cra << (STDBIT_INDXSRC - (CRABIT_INDXSRC_A + 1))) & STDMSK_INDXSRC) /*  IndxSrc  = IndxSrcA<1>. */
                 |((cra >> (CRABIT_INDXPOL_A - STDBIT_INDXPOL)) & STDMSK_INDXPOL)       /*  IndxPol  = IndxPolA. */
                 |((crb >> (CRBBIT_CLKENAB_A - STDBIT_CLKENAB)) & STDMSK_CLKENAB));     /*  ClkEnab  = ClkEnabA. */

        /*  Adjust mode-dependent parameters. */
        if (cra & (2 << CRABIT_CLKSRC_A))       /*  If Timer mode (ClkSrcA<1> == 1): */
                setup |= ((CLKSRC_TIMER << STDBIT_CLKSRC)       /*    Indicate Timer mode. */
                          |((cra << (STDBIT_CLKPOL - CRABIT_CLKSRC_A)) & STDMSK_CLKPOL) /*    Set ClkPol to indicate count direction (ClkSrcA<0>). */
                          |(MULT_X1 << STDBIT_CLKMULT));        /*    ClkMult must be 1x in Timer mode. */

        else                    /*  If Counter mode (ClkSrcA<1> == 0): */
                setup |= ((CLKSRC_COUNTER << STDBIT_CLKSRC)     /*    Indicate Counter mode. */
                          |((cra >> (CRABIT_CLKPOL_A - STDBIT_CLKPOL)) & STDMSK_CLKPOL) /*    Pass through ClkPol. */
                          |(((cra & CRAMSK_CLKMULT_A) == (MULT_X0 << CRABIT_CLKMULT_A)) ?       /*    Force ClkMult to 1x if not legal, else pass through. */
                            (MULT_X1 << STDBIT_CLKMULT) :
                            ((cra >> (CRABIT_CLKMULT_A -
                                      STDBIT_CLKMULT)) & STDMSK_CLKMULT)));

        /*  Return adjusted counter setup. */
        return setup;
}

static uint16_t GetMode_B(struct comedi_device *dev, struct enc_private *k)
{
        register uint16_t cra;
        register uint16_t crb;
        register uint16_t setup;

        /*  Fetch CRA and CRB register images. */
        cra = DEBIread(dev, k->MyCRA);
        crb = DEBIread(dev, k->MyCRB);

        /*  Populate the standardized counter setup bit fields.  Note: */
        /*  IndexSrc is restricted to ENC_X or IndxPol. */
        setup = (((crb << (STDBIT_INTSRC - CRBBIT_INTSRC_B)) & STDMSK_INTSRC)   /*  IntSrc   = IntSrcB. */
                 |((crb << (STDBIT_LATCHSRC - CRBBIT_LATCHSRC)) & STDMSK_LATCHSRC)      /*  LatchSrc = LatchSrcB. */
                 |((crb << (STDBIT_LOADSRC - CRBBIT_LOADSRC_B)) & STDMSK_LOADSRC)       /*  LoadSrc  = LoadSrcB. */
                 |((crb << (STDBIT_INDXPOL - CRBBIT_INDXPOL_B)) & STDMSK_INDXPOL)       /*  IndxPol  = IndxPolB. */
                 |((crb >> (CRBBIT_CLKENAB_B - STDBIT_CLKENAB)) & STDMSK_CLKENAB)       /*  ClkEnab  = ClkEnabB. */
                 |((cra >> ((CRABIT_INDXSRC_B + 1) - STDBIT_INDXSRC)) & STDMSK_INDXSRC));       /*  IndxSrc  = IndxSrcB<1>. */

        /*  Adjust mode-dependent parameters. */
        if ((crb & CRBMSK_CLKMULT_B) == (MULT_X0 << CRBBIT_CLKMULT_B))  /*  If Extender mode (ClkMultB == MULT_X0): */
                setup |= ((CLKSRC_EXTENDER << STDBIT_CLKSRC)    /*    Indicate Extender mode. */
                          |(MULT_X1 << STDBIT_CLKMULT)  /*    Indicate multiplier is 1x. */
                          |((cra >> (CRABIT_CLKSRC_B - STDBIT_CLKPOL)) & STDMSK_CLKPOL));       /*    Set ClkPol equal to Timer count direction (ClkSrcB<0>). */

        else if (cra & (2 << CRABIT_CLKSRC_B))  /*  If Timer mode (ClkSrcB<1> == 1): */
                setup |= ((CLKSRC_TIMER << STDBIT_CLKSRC)       /*    Indicate Timer mode. */
                          |(MULT_X1 << STDBIT_CLKMULT)  /*    Indicate multiplier is 1x. */
                          |((cra >> (CRABIT_CLKSRC_B - STDBIT_CLKPOL)) & STDMSK_CLKPOL));       /*    Set ClkPol equal to Timer count direction (ClkSrcB<0>). */

        else                    /*  If Counter mode (ClkSrcB<1> == 0): */
                setup |= ((CLKSRC_COUNTER << STDBIT_CLKSRC)     /*    Indicate Timer mode. */
                          |((crb >> (CRBBIT_CLKMULT_B - STDBIT_CLKMULT)) & STDMSK_CLKMULT)      /*    Clock multiplier is passed through. */
                          |((crb << (STDBIT_CLKPOL - CRBBIT_CLKPOL_B)) & STDMSK_CLKPOL));       /*    Clock polarity is passed through. */

        /*  Return adjusted counter setup. */
        return setup;
}

/*
 * Set the operating mode for the specified counter.  The setup
 * parameter is treated as a COUNTER_SETUP data type.  The following
 * parameters are programmable (all other parms are ignored): ClkMult,
 * ClkPol, ClkEnab, IndexSrc, IndexPol, LoadSrc.
 */

static void SetMode_A(struct comedi_device *dev, struct enc_private *k,
                      uint16_t Setup, uint16_t DisableIntSrc)
{
        register uint16_t cra;
        register uint16_t crb;
        register uint16_t setup = Setup;        /*  Cache the Standard Setup. */

        /*  Initialize CRA and CRB images. */
        cra = ((setup & CRAMSK_LOADSRC_A)       /*  Preload trigger is passed through. */
               |((setup & STDMSK_INDXSRC) >> (STDBIT_INDXSRC - (CRABIT_INDXSRC_A + 1))));       /*  IndexSrc is restricted to ENC_X or IndxPol. */

        crb = (CRBMSK_INTRESETCMD | CRBMSK_INTRESET_A   /*  Reset any pending CounterA event captures. */
               | ((setup & STDMSK_CLKENAB) << (CRBBIT_CLKENAB_A - STDBIT_CLKENAB)));    /*  Clock enable is passed through. */

        /*  Force IntSrc to Disabled if DisableIntSrc is asserted. */
        if (!DisableIntSrc)
                cra |= ((setup & STDMSK_INTSRC) >> (STDBIT_INTSRC -
                                                    CRABIT_INTSRC_A));

        /*  Populate all mode-dependent attributes of CRA & CRB images. */
        switch ((setup & STDMSK_CLKSRC) >> STDBIT_CLKSRC) {
        case CLKSRC_EXTENDER:   /*  Extender Mode: Force to Timer mode */
                /*  (Extender valid only for B counters). */

        case CLKSRC_TIMER:      /*  Timer Mode: */
                cra |= ((2 << CRABIT_CLKSRC_A)  /*    ClkSrcA<1> selects system clock */
                        |((setup & STDMSK_CLKPOL) >> (STDBIT_CLKPOL - CRABIT_CLKSRC_A)) /*      with count direction (ClkSrcA<0>) obtained from ClkPol. */
                        |(1 << CRABIT_CLKPOL_A) /*    ClkPolA behaves as always-on clock enable. */
                        |(MULT_X1 << CRABIT_CLKMULT_A));        /*    ClkMult must be 1x. */
                break;

        default:                /*  Counter Mode: */
                cra |= (CLKSRC_COUNTER  /*    Select ENC_C and ENC_D as clock/direction inputs. */
                        | ((setup & STDMSK_CLKPOL) << (CRABIT_CLKPOL_A - STDBIT_CLKPOL))        /*    Clock polarity is passed through. */
                        |(((setup & STDMSK_CLKMULT) == (MULT_X0 << STDBIT_CLKMULT)) ?   /*    Force multiplier to x1 if not legal, otherwise pass through. */
                          (MULT_X1 << CRABIT_CLKMULT_A) :
                          ((setup & STDMSK_CLKMULT) << (CRABIT_CLKMULT_A -
                                                        STDBIT_CLKMULT))));
        }

        /*  Force positive index polarity if IndxSrc is software-driven only, */
        /*  otherwise pass it through. */
        if (~setup & STDMSK_INDXSRC)
                cra |= ((setup & STDMSK_INDXPOL) << (CRABIT_INDXPOL_A -
                                                     STDBIT_INDXPOL));

        /*  If IntSrc has been forced to Disabled, update the MISC2 interrupt */
        /*  enable mask to indicate the counter interrupt is disabled. */
        if (DisableIntSrc)
                devpriv->CounterIntEnabs &= ~k->MyEventBits[3];

        /*  While retaining CounterB and LatchSrc configurations, program the */
        /*  new counter operating mode. */
        DEBIreplace(dev, k->MyCRA, CRAMSK_INDXSRC_B | CRAMSK_CLKSRC_B, cra);
        DEBIreplace(dev, k->MyCRB,
                    (uint16_t) (~(CRBMSK_INTCTRL | CRBMSK_CLKENAB_A)), crb);

}

static void SetMode_B(struct comedi_device *dev, struct enc_private *k,
                      uint16_t Setup, uint16_t DisableIntSrc)
{
        register uint16_t cra;
        register uint16_t crb;
        register uint16_t setup = Setup;        /*  Cache the Standard Setup. */

        /*  Initialize CRA and CRB images. */
        cra = ((setup & STDMSK_INDXSRC) << ((CRABIT_INDXSRC_B + 1) - STDBIT_INDXSRC));  /*  IndexSrc field is restricted to ENC_X or IndxPol. */

        crb = (CRBMSK_INTRESETCMD | CRBMSK_INTRESET_B   /*  Reset event captures and disable interrupts. */
               | ((setup & STDMSK_CLKENAB) << (CRBBIT_CLKENAB_B - STDBIT_CLKENAB))      /*  Clock enable is passed through. */
               |((setup & STDMSK_LOADSRC) >> (STDBIT_LOADSRC - CRBBIT_LOADSRC_B)));     /*  Preload trigger source is passed through. */

        /*  Force IntSrc to Disabled if DisableIntSrc is asserted. */
        if (!DisableIntSrc)
                crb |= ((setup & STDMSK_INTSRC) >> (STDBIT_INTSRC -
                                                    CRBBIT_INTSRC_B));

        /*  Populate all mode-dependent attributes of CRA & CRB images. */
        switch ((setup & STDMSK_CLKSRC) >> STDBIT_CLKSRC) {
        case CLKSRC_TIMER:      /*  Timer Mode: */
                cra |= ((2 << CRABIT_CLKSRC_B)  /*    ClkSrcB<1> selects system clock */
                        |((setup & STDMSK_CLKPOL) << (CRABIT_CLKSRC_B - STDBIT_CLKPOL)));       /*      with direction (ClkSrcB<0>) obtained from ClkPol. */
                crb |= ((1 << CRBBIT_CLKPOL_B)  /*    ClkPolB behaves as always-on clock enable. */
                        |(MULT_X1 << CRBBIT_CLKMULT_B));        /*    ClkMultB must be 1x. */
                break;

        case CLKSRC_EXTENDER:   /*  Extender Mode: */
                cra |= ((2 << CRABIT_CLKSRC_B)  /*    ClkSrcB source is OverflowA (same as "timer") */
                        |((setup & STDMSK_CLKPOL) << (CRABIT_CLKSRC_B - STDBIT_CLKPOL)));       /*      with direction obtained from ClkPol. */
                crb |= ((1 << CRBBIT_CLKPOL_B)  /*    ClkPolB controls IndexB -- always set to active. */
                        |(MULT_X0 << CRBBIT_CLKMULT_B));        /*    ClkMultB selects OverflowA as the clock source. */
                break;

        default:                /*  Counter Mode: */
                cra |= (CLKSRC_COUNTER << CRABIT_CLKSRC_B);     /*    Select ENC_C and ENC_D as clock/direction inputs. */
                crb |= (((setup & STDMSK_CLKPOL) >> (STDBIT_CLKPOL - CRBBIT_CLKPOL_B))  /*    ClkPol is passed through. */
                        |(((setup & STDMSK_CLKMULT) == (MULT_X0 << STDBIT_CLKMULT)) ?   /*    Force ClkMult to x1 if not legal, otherwise pass through. */
                          (MULT_X1 << CRBBIT_CLKMULT_B) :
                          ((setup & STDMSK_CLKMULT) << (CRBBIT_CLKMULT_B -
                                                        STDBIT_CLKMULT))));
        }

        /*  Force positive index polarity if IndxSrc is software-driven only, */
        /*  otherwise pass it through. */
        if (~setup & STDMSK_INDXSRC)
                crb |= ((setup & STDMSK_INDXPOL) >> (STDBIT_INDXPOL -
                                                     CRBBIT_INDXPOL_B));

        /*  If IntSrc has been forced to Disabled, update the MISC2 interrupt */
        /*  enable mask to indicate the counter interrupt is disabled. */
        if (DisableIntSrc)
                devpriv->CounterIntEnabs &= ~k->MyEventBits[3];

        /*  While retaining CounterA and LatchSrc configurations, program the */
        /*  new counter operating mode. */
        DEBIreplace(dev, k->MyCRA,
                    (uint16_t) (~(CRAMSK_INDXSRC_B | CRAMSK_CLKSRC_B)), cra);
        DEBIreplace(dev, k->MyCRB, CRBMSK_CLKENAB_A | CRBMSK_LATCHSRC, crb);
}

/*  Return/set a counter's enable.  enab: 0=always enabled, 1=enabled by index. */

static void SetEnable_A(struct comedi_device *dev, struct enc_private *k,
                        uint16_t enab)
{
        DEBUG("SetEnable_A: SetEnable_A enter 3541\n");
        DEBIreplace(dev, k->MyCRB,
                    (uint16_t) (~(CRBMSK_INTCTRL | CRBMSK_CLKENAB_A)),
                    (uint16_t) (enab << CRBBIT_CLKENAB_A));
}

static void SetEnable_B(struct comedi_device *dev, struct enc_private *k,
                        uint16_t enab)
{
        DEBIreplace(dev, k->MyCRB,
                    (uint16_t) (~(CRBMSK_INTCTRL | CRBMSK_CLKENAB_B)),
                    (uint16_t) (enab << CRBBIT_CLKENAB_B));
}

static uint16_t GetEnable_A(struct comedi_device *dev, struct enc_private *k)
{
        return (DEBIread(dev, k->MyCRB) >> CRBBIT_CLKENAB_A) & 1;
}

static uint16_t GetEnable_B(struct comedi_device *dev, struct enc_private *k)
{
        return (DEBIread(dev, k->MyCRB) >> CRBBIT_CLKENAB_B) & 1;
}

/* Return/set a counter pair's latch trigger source.  0: On read
 * access, 1: A index latches A, 2: B index latches B, 3: A overflow
 * latches B.
 */

static void SetLatchSource(struct comedi_device *dev, struct enc_private *k,
                           uint16_t value)
{
        DEBUG("SetLatchSource: SetLatchSource enter 3550 \n");
        DEBIreplace(dev, k->MyCRB,
                    (uint16_t) (~(CRBMSK_INTCTRL | CRBMSK_LATCHSRC)),
                    (uint16_t) (value << CRBBIT_LATCHSRC));

        DEBUG("SetLatchSource: SetLatchSource exit \n");
}

/*
 * static uint16_t GetLatchSource(struct comedi_device *dev, struct enc_private *k )
 * {
 *      return ( DEBIread( dev, k->MyCRB) >> CRBBIT_LATCHSRC ) & 3;
 * }
 */

/*
 * Return/set the event that will trigger transfer of the preload
 * register into the counter.  0=ThisCntr_Index, 1=ThisCntr_Overflow,
 * 2=OverflowA (B counters only), 3=disabled.
 */

static void SetLoadTrig_A(struct comedi_device *dev, struct enc_private *k,
                          uint16_t Trig)
{
        DEBIreplace(dev, k->MyCRA, (uint16_t) (~CRAMSK_LOADSRC_A),
                    (uint16_t) (Trig << CRABIT_LOADSRC_A));
}

static void SetLoadTrig_B(struct comedi_device *dev, struct enc_private *k,
                          uint16_t Trig)
{
        DEBIreplace(dev, k->MyCRB,
                    (uint16_t) (~(CRBMSK_LOADSRC_B | CRBMSK_INTCTRL)),
                    (uint16_t) (Trig << CRBBIT_LOADSRC_B));
}

static uint16_t GetLoadTrig_A(struct comedi_device *dev, struct enc_private *k)
{
        return (DEBIread(dev, k->MyCRA) >> CRABIT_LOADSRC_A) & 3;
}

static uint16_t GetLoadTrig_B(struct comedi_device *dev, struct enc_private *k)
{
        return (DEBIread(dev, k->MyCRB) >> CRBBIT_LOADSRC_B) & 3;
}

/* Return/set counter interrupt source and clear any captured
 * index/overflow events.  IntSource: 0=Disabled, 1=OverflowOnly,
 * 2=IndexOnly, 3=IndexAndOverflow.
 */

static void SetIntSrc_A(struct comedi_device *dev, struct enc_private *k,
                        uint16_t IntSource)
{
        /*  Reset any pending counter overflow or index captures. */
        DEBIreplace(dev, k->MyCRB, (uint16_t) (~CRBMSK_INTCTRL),
                    CRBMSK_INTRESETCMD | CRBMSK_INTRESET_A);

        /*  Program counter interrupt source. */
        DEBIreplace(dev, k->MyCRA, ~CRAMSK_INTSRC_A,
                    (uint16_t) (IntSource << CRABIT_INTSRC_A));

        /*  Update MISC2 interrupt enable mask. */
        devpriv->CounterIntEnabs =
            (devpriv->CounterIntEnabs & ~k->
             MyEventBits[3]) | k->MyEventBits[IntSource];
}

static void SetIntSrc_B(struct comedi_device *dev, struct enc_private *k,
                        uint16_t IntSource)
{
        uint16_t crb;

        /*  Cache writeable CRB register image. */
        crb = DEBIread(dev, k->MyCRB) & ~CRBMSK_INTCTRL;

        /*  Reset any pending counter overflow or index captures. */
        DEBIwrite(dev, k->MyCRB,
                  (uint16_t) (crb | CRBMSK_INTRESETCMD | CRBMSK_INTRESET_B));

        /*  Program counter interrupt source. */
        DEBIwrite(dev, k->MyCRB,
                  (uint16_t) ((crb & ~CRBMSK_INTSRC_B) | (IntSource <<
                                                          CRBBIT_INTSRC_B)));

        /*  Update MISC2 interrupt enable mask. */
        devpriv->CounterIntEnabs =
            (devpriv->CounterIntEnabs & ~k->
             MyEventBits[3]) | k->MyEventBits[IntSource];
}

static uint16_t GetIntSrc_A(struct comedi_device *dev, struct enc_private *k)
{
        return (DEBIread(dev, k->MyCRA) >> CRABIT_INTSRC_A) & 3;
}

static uint16_t GetIntSrc_B(struct comedi_device *dev, struct enc_private *k)
{
        return (DEBIread(dev, k->MyCRB) >> CRBBIT_INTSRC_B) & 3;
}

/*  Return/set the clock multiplier. */

/* static void SetClkMult(struct comedi_device *dev, struct enc_private *k, uint16_t value )  */
/* { */
/*   k->SetMode(dev, k, (uint16_t)( ( k->GetMode(dev, k ) & ~STDMSK_CLKMULT ) | ( value << STDBIT_CLKMULT ) ), FALSE ); */
/* } */

/* static uint16_t GetClkMult(struct comedi_device *dev, struct enc_private *k )  */
/* { */
/*   return ( k->GetMode(dev, k ) >> STDBIT_CLKMULT ) & 3; */
/* } */

/* Return/set the clock polarity. */

/* static void SetClkPol( struct comedi_device *dev,struct enc_private *k, uint16_t value )  */
/* { */
/*   k->SetMode(dev, k, (uint16_t)( ( k->GetMode(dev, k ) & ~STDMSK_CLKPOL ) | ( value << STDBIT_CLKPOL ) ), FALSE ); */
/* } */

/* static uint16_t GetClkPol(struct comedi_device *dev, struct enc_private *k )  */
/* { */
/*   return ( k->GetMode(dev, k ) >> STDBIT_CLKPOL ) & 1; */
/* } */

/* Return/set the clock source.  */

/* static void SetClkSrc( struct comedi_device *dev,struct enc_private *k, uint16_t value )  */
/* { */
/*   k->SetMode(dev, k, (uint16_t)( ( k->GetMode(dev, k ) & ~STDMSK_CLKSRC ) | ( value << STDBIT_CLKSRC ) ), FALSE ); */
/* } */

/* static uint16_t GetClkSrc( struct comedi_device *dev,struct enc_private *k )  */
/* { */
/*   return ( k->GetMode(dev, k ) >> STDBIT_CLKSRC ) & 3; */
/* } */

/* Return/set the index polarity. */

/* static void SetIndexPol(struct comedi_device *dev, struct enc_private *k, uint16_t value )  */
/* { */
/*   k->SetMode(dev, k, (uint16_t)( ( k->GetMode(dev, k ) & ~STDMSK_INDXPOL ) | ( (value != 0) << STDBIT_INDXPOL ) ), FALSE ); */
/* } */

/* static uint16_t GetIndexPol(struct comedi_device *dev, struct enc_private *k )  */
/* { */
/*   return ( k->GetMode(dev, k ) >> STDBIT_INDXPOL ) & 1; */
/* } */

/*  Return/set the index source. */

/* static void SetIndexSrc(struct comedi_device *dev, struct enc_private *k, uint16_t value )  */
/* { */
/*   DEBUG("SetIndexSrc: set index src enter 3700\n"); */
/*   k->SetMode(dev, k, (uint16_t)( ( k->GetMode(dev, k ) & ~STDMSK_INDXSRC ) | ( (value != 0) << STDBIT_INDXSRC ) ), FALSE ); */
/* } */

/* static uint16_t GetIndexSrc(struct comedi_device *dev, struct enc_private *k )  */
/* { */
/*   return ( k->GetMode(dev, k ) >> STDBIT_INDXSRC ) & 1; */
/* } */

/*  Generate an index pulse. */

static void PulseIndex_A(struct comedi_device *dev, struct enc_private *k)
{
        register uint16_t cra;

        DEBUG("PulseIndex_A: pulse index enter\n");

        cra = DEBIread(dev, k->MyCRA);  /*  Pulse index. */
        DEBIwrite(dev, k->MyCRA, (uint16_t) (cra ^ CRAMSK_INDXPOL_A));
        DEBUG("PulseIndex_A: pulse index step1\n");
        DEBIwrite(dev, k->MyCRA, cra);
}

static void PulseIndex_B(struct comedi_device *dev, struct enc_private *k)
{
        register uint16_t crb;

        crb = DEBIread(dev, k->MyCRB) & ~CRBMSK_INTCTRL;        /*  Pulse index. */
        DEBIwrite(dev, k->MyCRB, (uint16_t) (crb ^ CRBMSK_INDXPOL_B));
        DEBIwrite(dev, k->MyCRB, crb);
}

/*  Write value into counter preload register. */

static void Preload(struct comedi_device *dev, struct enc_private *k,
                    uint32_t value)
{
        DEBUG("Preload: preload enter\n");
        DEBIwrite(dev, (uint16_t) (k->MyLatchLsw), (uint16_t) value);   /*  Write value to preload register. */
        DEBUG("Preload: preload step 1\n");
        DEBIwrite(dev, (uint16_t) (k->MyLatchLsw + 2),
                  (uint16_t) (value >> 16));
}

static void CountersInit(struct comedi_device *dev)
{
        int chan;
        struct enc_private *k;
        uint16_t Setup = (LOADSRC_INDX << BF_LOADSRC) | /*  Preload upon */
            /*  index. */
            (INDXSRC_SOFT << BF_INDXSRC) |      /*  Disable hardware index. */
            (CLKSRC_COUNTER << BF_CLKSRC) |     /*  Operating mode is counter. */
            (CLKPOL_POS << BF_CLKPOL) | /*  Active high clock. */
            (CNTDIR_UP << BF_CLKPOL) |  /*  Count direction is up. */
            (CLKMULT_1X << BF_CLKMULT) |        /*  Clock multiplier is 1x. */
            (CLKENAB_INDEX << BF_CLKENAB);      /*  Enabled by index */

        /*  Disable all counter interrupts and clear any captured counter events. */
        for (chan = 0; chan < S626_ENCODER_CHANNELS; chan++) {
                k = &encpriv[chan];
                k->SetMode(dev, k, Setup, TRUE);
                k->SetIntSrc(dev, k, 0);
                k->ResetCapFlags(dev, k);
                k->SetEnable(dev, k, CLKENAB_ALWAYS);
        }
        DEBUG("CountersInit: counters initialized \n");

}