// SPDX-License-Identifier: GPL-2.0+
/*
 * comedi/drivers/cb_pcidas64.c
 * This is a driver for the ComputerBoards/MeasurementComputing PCI-DAS
 * 64xx, 60xx, and 4020 cards.
 *
 * Author:  Frank Mori Hess <fmhess@users.sourceforge.net>
 * Copyright (C) 2001, 2002 Frank Mori Hess
 *
 * Thanks also go to the following people:
 *
 * Steve Rosenbluth, for providing the source code for
 * his pci-das6402 driver, and source code for working QNX pci-6402
 * drivers by Greg Laird and Mariusz Bogacz.  None of the code was
 * used directly here, but it was useful as an additional source of
 * documentation on how to program the boards.
 *
 * John Sims, for much testing and feedback on pcidas-4020 support.
 *
 * COMEDI - Linux Control and Measurement Device Interface
 * Copyright (C) 1997-8 David A. Schleef <ds@schleef.org>
 */

/*
 * Driver: cb_pcidas64
 * Description: MeasurementComputing PCI-DAS64xx, 60XX, and 4020 series
 *   with the PLX 9080 PCI controller
 * Author: Frank Mori Hess <fmhess@users.sourceforge.net>
 * Status: works
 * Updated: Fri, 02 Nov 2012 18:58:55 +0000
 * Devices: [Measurement Computing] PCI-DAS6402/16 (cb_pcidas64),
 *   PCI-DAS6402/12, PCI-DAS64/M1/16, PCI-DAS64/M2/16,
 *   PCI-DAS64/M3/16, PCI-DAS6402/16/JR, PCI-DAS64/M1/16/JR,
 *   PCI-DAS64/M2/16/JR, PCI-DAS64/M3/16/JR, PCI-DAS64/M1/14,
 *   PCI-DAS64/M2/14, PCI-DAS64/M3/14, PCI-DAS6013, PCI-DAS6014,
 *   PCI-DAS6023, PCI-DAS6025, PCI-DAS6030,
 *   PCI-DAS6031, PCI-DAS6032, PCI-DAS6033, PCI-DAS6034,
 *   PCI-DAS6035, PCI-DAS6036, PCI-DAS6040, PCI-DAS6052,
 *   PCI-DAS6070, PCI-DAS6071, PCI-DAS4020/12
 *
 * Configuration options:
 *   None.
 *
 * Manual attachment of PCI cards with the comedi_config utility is not
 * supported by this driver; they are attached automatically.
 *
 * These boards may be autocalibrated with the comedi_calibrate utility.
 *
 * To select the bnc trigger input on the 4020 (instead of the dio input),
 * specify a nonzero channel in the chanspec.  If you wish to use an external
 * master clock on the 4020, you may do so by setting the scan_begin_src
 * to TRIG_OTHER, and using an INSN_CONFIG_TIMER_1 configuration insn
 * to configure the divisor to use for the external clock.
 *
 * Some devices are not identified because the PCI device IDs are not yet
 * known. If you have such a board, please let the maintainers know.
 */

/*
 * TODO:
 * make it return error if user attempts an ai command that uses the
 * external queue, and an ao command simultaneously user counter subdevice
 * there are a number of boards this driver will support when they are
 * fully released, but does not yet since the pci device id numbers
 * are not yet available.
 *
 * support prescaled 100khz clock for slow pacing (not available on 6000
 * series?)
 *
 * make ao fifo size adjustable like ai fifo
 */

#include <linux/module.h>
#include <linux/delay.h>
#include <linux/interrupt.h>

#include "../comedi_pci.h"

#include "8255.h"
#include "plx9080.h"

#define TIMER_BASE 25		/*  40MHz master clock */
/*
 * 100kHz 'prescaled' clock for slow acquisition,
 * maybe I'll support this someday
 */
#define PRESCALED_TIMER_BASE	10000
#define DMA_BUFFER_SIZE		0x1000
#define DAC_FIFO_SIZE		0x2000

/* maximum value that can be loaded into board's 24-bit counters */
static const int max_counter_value = 0xffffff;

/* PCI-DAS64xxx base addresses */

/* devpriv->main_iobase registers */
enum write_only_registers {
	INTR_ENABLE_REG = 0x0,		/* interrupt enable register */
	HW_CONFIG_REG = 0x2,		/* hardware config register */
	DAQ_SYNC_REG = 0xc,
	DAQ_ATRIG_LOW_4020_REG = 0xc,
	ADC_CONTROL0_REG = 0x10,	/* adc control register 0 */
	ADC_CONTROL1_REG = 0x12,	/* adc control register 1 */
	CALIBRATION_REG = 0x14,
	/* lower 16 bits of adc sample interval counter */
	ADC_SAMPLE_INTERVAL_LOWER_REG = 0x16,
	/* upper 8 bits of adc sample interval counter */
	ADC_SAMPLE_INTERVAL_UPPER_REG = 0x18,
	/* lower 16 bits of delay interval counter */
	ADC_DELAY_INTERVAL_LOWER_REG = 0x1a,
	/* upper 8 bits of delay interval counter */
	ADC_DELAY_INTERVAL_UPPER_REG = 0x1c,
	/* lower 16 bits of hardware conversion/scan counter */
	ADC_COUNT_LOWER_REG = 0x1e,
	/* upper 8 bits of hardware conversion/scan counter */
	ADC_COUNT_UPPER_REG = 0x20,
	ADC_START_REG = 0x22,	/* software trigger to start acquisition */
	ADC_CONVERT_REG = 0x24,	/* initiates single conversion */
	ADC_QUEUE_CLEAR_REG = 0x26,	/* clears adc queue */
	ADC_QUEUE_LOAD_REG = 0x28,	/* loads adc queue */
	ADC_BUFFER_CLEAR_REG = 0x2a,
	/* high channel for internal queue, use adc_chan_bits() inline above */
	ADC_QUEUE_HIGH_REG = 0x2c,
	DAC_CONTROL0_REG = 0x50,	/* dac control register 0 */
	DAC_CONTROL1_REG = 0x52,	/* dac control register 0 */
	/* lower 16 bits of dac sample interval counter */
	DAC_SAMPLE_INTERVAL_LOWER_REG = 0x54,
	/* upper 8 bits of dac sample interval counter */
	DAC_SAMPLE_INTERVAL_UPPER_REG = 0x56,
	DAC_SELECT_REG = 0x60,
	DAC_START_REG = 0x64,
	DAC_BUFFER_CLEAR_REG = 0x66,	/* clear dac buffer */
};

static inline unsigned int dac_convert_reg(unsigned int channel)
{
	return 0x70 + (2 * (channel & 0x1));
}

static inline unsigned int dac_lsb_4020_reg(unsigned int channel)
{
	return 0x70 + (4 * (channel & 0x1));
}

static inline unsigned int dac_msb_4020_reg(unsigned int channel)
{
	return 0x72 + (4 * (channel & 0x1));
}

enum read_only_registers {
	/*
	 * hardware status register,
	 * reading this apparently clears pending interrupts as well
	 */
	HW_STATUS_REG = 0x0,
	PIPE1_READ_REG = 0x4,
	ADC_READ_PNTR_REG = 0x8,
	LOWER_XFER_REG = 0x10,
	ADC_WRITE_PNTR_REG = 0xc,
	PREPOST_REG = 0x14,
};

enum read_write_registers {
	I8255_4020_REG = 0x48,	/* 8255 offset, for 4020 only */
	/* external channel/gain queue, uses same bits as ADC_QUEUE_LOAD_REG */
	ADC_QUEUE_FIFO_REG = 0x100,
	ADC_FIFO_REG = 0x200,	/* adc data fifo */
	/* dac data fifo, has weird interactions with external channel queue */
	DAC_FIFO_REG = 0x300,
};

/* dev->mmio registers */
enum dio_counter_registers {
	DIO_8255_OFFSET = 0x0,
	DO_REG = 0x20,
	DI_REG = 0x28,
	DIO_DIRECTION_60XX_REG = 0x40,
	DIO_DATA_60XX_REG = 0x48,
};

/* bit definitions for write-only registers */

enum intr_enable_contents {
	ADC_INTR_SRC_MASK = 0x3,	/* adc interrupt source mask */
	ADC_INTR_QFULL_BITS = 0x0,	/* interrupt fifo quarter full */
	ADC_INTR_EOC_BITS = 0x1,	/* interrupt end of conversion */
	ADC_INTR_EOSCAN_BITS = 0x2,	/* interrupt end of scan */
	ADC_INTR_EOSEQ_BITS = 0x3,	/* interrupt end of sequence mask */
	EN_ADC_INTR_SRC_BIT = 0x4,	/* enable adc interrupt source */
	EN_ADC_DONE_INTR_BIT = 0x8,	/* enable adc acquisition done intr */
	DAC_INTR_SRC_MASK = 0x30,
	DAC_INTR_QEMPTY_BITS = 0x0,
	DAC_INTR_HIGH_CHAN_BITS = 0x10,
	EN_DAC_INTR_SRC_BIT = 0x40,	/* enable dac interrupt source */
	EN_DAC_DONE_INTR_BIT = 0x80,
	EN_ADC_ACTIVE_INTR_BIT = 0x200,	/* enable adc active interrupt */
	EN_ADC_STOP_INTR_BIT = 0x400,	/* enable adc stop trigger interrupt */
	EN_DAC_ACTIVE_INTR_BIT = 0x800,	/* enable dac active interrupt */
	EN_DAC_UNDERRUN_BIT = 0x4000,	/* enable dac underrun status bit */
	EN_ADC_OVERRUN_BIT = 0x8000,	/* enable adc overrun status bit */
};

enum hw_config_contents {
	MASTER_CLOCK_4020_MASK = 0x3,	/* master clock source mask for 4020 */
	INTERNAL_CLOCK_4020_BITS = 0x1,	/* use 40 MHz internal master clock */
	BNC_CLOCK_4020_BITS = 0x2,	/* use BNC input for master clock */
	EXT_CLOCK_4020_BITS = 0x3,	/* use dio input for master clock */
	EXT_QUEUE_BIT = 0x200,		/* use external channel/gain queue */
	/* use 225 nanosec strobe when loading dac instead of 50 nanosec */
	SLOW_DAC_BIT = 0x400,
	/*
	 * bit with unknown function yet given as default value in pci-das64
	 * manual
	 */
	HW_CONFIG_DUMMY_BITS = 0x2000,
	/* bit selects channels 1/0 for analog input/output, otherwise 0/1 */
	DMA_CH_SELECT_BIT = 0x8000,
	FIFO_SIZE_REG = 0x4,		/* allows adjustment of fifo sizes */
	DAC_FIFO_SIZE_MASK = 0xff00,	/* bits that set dac fifo size */
	DAC_FIFO_BITS = 0xf800,		/* 8k sample ao fifo */
};

enum daq_atrig_low_4020_contents {
	/* use trig/ext clk bnc input for analog gate signal */
	EXT_AGATE_BNC_BIT = 0x8000,
	/* use trig/ext clk bnc input for external stop trigger signal */
	EXT_STOP_TRIG_BNC_BIT = 0x4000,
	/* use trig/ext clk bnc input for external start trigger signal */
	EXT_START_TRIG_BNC_BIT = 0x2000,
};

enum adc_control0_contents {
	ADC_GATE_SRC_MASK = 0x3,	/* bits that select gate */
	ADC_SOFT_GATE_BITS = 0x1,	/* software gate */
	ADC_EXT_GATE_BITS = 0x2,	/* external digital gate */
	ADC_ANALOG_GATE_BITS = 0x3,	/* analog level gate */
	/* level-sensitive gate (for digital) */
	ADC_GATE_LEVEL_BIT = 0x4,
	ADC_GATE_POLARITY_BIT = 0x8,	/* gate active low */
	ADC_START_TRIG_SOFT_BITS = 0x10,
	ADC_START_TRIG_EXT_BITS = 0x20,
	ADC_START_TRIG_ANALOG_BITS = 0x30,
	ADC_START_TRIG_MASK = 0x30,
	ADC_START_TRIG_FALLING_BIT = 0x40,	/* trig 1 uses falling edge */
	/* external pacing uses falling edge */
	ADC_EXT_CONV_FALLING_BIT = 0x800,
	/* enable hardware scan counter */
	ADC_SAMPLE_COUNTER_EN_BIT = 0x1000,
	ADC_DMA_DISABLE_BIT = 0x4000,	/* disables dma */
	ADC_ENABLE_BIT = 0x8000,	/* master adc enable */
};

enum adc_control1_contents {
	/* should be set for boards with > 16 channels */
	ADC_QUEUE_CONFIG_BIT = 0x1,
	CONVERT_POLARITY_BIT = 0x10,
	EOC_POLARITY_BIT = 0x20,
	ADC_SW_GATE_BIT = 0x40,		/* software gate of adc */
	ADC_DITHER_BIT = 0x200,		/* turn on extra noise for dithering */
	RETRIGGER_BIT = 0x800,
	ADC_LO_CHANNEL_4020_MASK = 0x300,
	ADC_HI_CHANNEL_4020_MASK = 0xc00,
	TWO_CHANNEL_4020_BITS = 0x1000,		/* two channel mode for 4020 */
	FOUR_CHANNEL_4020_BITS = 0x2000,	/* four channel mode for 4020 */
	CHANNEL_MODE_4020_MASK = 0x3000,
	ADC_MODE_MASK = 0xf000,
};

static inline u16 adc_lo_chan_4020_bits(unsigned int channel)
{
	return (channel & 0x3) << 8;
};

static inline u16 adc_hi_chan_4020_bits(unsigned int channel)
{
	return (channel & 0x3) << 10;
};

static inline u16 adc_mode_bits(unsigned int mode)
{
	return (mode & 0xf) << 12;
};

enum calibration_contents {
	SELECT_8800_BIT = 0x1,
	SELECT_8402_64XX_BIT = 0x2,
	SELECT_1590_60XX_BIT = 0x2,
	CAL_EN_64XX_BIT = 0x40,		/* calibration enable for 64xx series */
	SERIAL_DATA_IN_BIT = 0x80,
	SERIAL_CLOCK_BIT = 0x100,
	CAL_EN_60XX_BIT = 0x200,	/* calibration enable for 60xx series */
	CAL_GAIN_BIT = 0x800,
};

/*
 * calibration sources for 6025 are:
 *  0 : ground
 *  1 : 10V
 *  2 : 5V
 *  3 : 0.5V
 *  4 : 0.05V
 *  5 : ground
 *  6 : dac channel 0
 *  7 : dac channel 1
 */

static inline u16 adc_src_bits(unsigned int source)
{
	return (source & 0xf) << 3;
};

static inline u16 adc_convert_chan_4020_bits(unsigned int channel)
{
	return (channel & 0x3) << 8;
};

enum adc_queue_load_contents {
	UNIP_BIT = 0x800,		/* unipolar/bipolar bit */
	ADC_SE_DIFF_BIT = 0x1000,	/* single-ended/ differential bit */
	/* non-referenced single-ended (common-mode input) */
	ADC_COMMON_BIT = 0x2000,
	QUEUE_EOSEQ_BIT = 0x4000,	/* queue end of sequence */
	QUEUE_EOSCAN_BIT = 0x8000,	/* queue end of scan */
};

static inline u16 adc_chan_bits(unsigned int channel)
{
	return channel & 0x3f;
};

enum dac_control0_contents {
	DAC_ENABLE_BIT = 0x8000,	/* dac controller enable bit */
	DAC_CYCLIC_STOP_BIT = 0x4000,
	DAC_WAVEFORM_MODE_BIT = 0x100,
	DAC_EXT_UPDATE_FALLING_BIT = 0x80,
	DAC_EXT_UPDATE_ENABLE_BIT = 0x40,
	WAVEFORM_TRIG_MASK = 0x30,
	WAVEFORM_TRIG_DISABLED_BITS = 0x0,
	WAVEFORM_TRIG_SOFT_BITS = 0x10,
	WAVEFORM_TRIG_EXT_BITS = 0x20,
	WAVEFORM_TRIG_ADC1_BITS = 0x30,
	WAVEFORM_TRIG_FALLING_BIT = 0x8,
	WAVEFORM_GATE_LEVEL_BIT = 0x4,
	WAVEFORM_GATE_ENABLE_BIT = 0x2,
	WAVEFORM_GATE_SELECT_BIT = 0x1,
};

enum dac_control1_contents {
	DAC_WRITE_POLARITY_BIT = 0x800,	/* board-dependent setting */
	DAC1_EXT_REF_BIT = 0x200,
	DAC0_EXT_REF_BIT = 0x100,
	DAC_OUTPUT_ENABLE_BIT = 0x80,	/* dac output enable bit */
	DAC_UPDATE_POLARITY_BIT = 0x40,	/* board-dependent setting */
	DAC_SW_GATE_BIT = 0x20,
	DAC1_UNIPOLAR_BIT = 0x8,
	DAC0_UNIPOLAR_BIT = 0x2,
};

/* bit definitions for read-only registers */
enum hw_status_contents {
	DAC_UNDERRUN_BIT = 0x1,
	ADC_OVERRUN_BIT = 0x2,
	DAC_ACTIVE_BIT = 0x4,
	ADC_ACTIVE_BIT = 0x8,
	DAC_INTR_PENDING_BIT = 0x10,
	ADC_INTR_PENDING_BIT = 0x20,
	DAC_DONE_BIT = 0x40,
	ADC_DONE_BIT = 0x80,
	EXT_INTR_PENDING_BIT = 0x100,
	ADC_STOP_BIT = 0x200,
};

static inline u16 pipe_full_bits(u16 hw_status_bits)
{
	return (hw_status_bits >> 10) & 0x3;
};

static inline unsigned int dma_chain_flag_bits(u16 prepost_bits)
{
	return (prepost_bits >> 6) & 0x3;
}

static inline unsigned int adc_upper_read_ptr_code(u16 prepost_bits)
{
	return (prepost_bits >> 12) & 0x3;
}

static inline unsigned int adc_upper_write_ptr_code(u16 prepost_bits)
{
	return (prepost_bits >> 14) & 0x3;
}

/* I2C addresses for 4020 */
enum i2c_addresses {
	RANGE_CAL_I2C_ADDR = 0x20,
	CALDAC0_I2C_ADDR = 0xc,
	CALDAC1_I2C_ADDR = 0xd,
};

enum range_cal_i2c_contents {
	/* bits that set what source the adc converter measures */
	ADC_SRC_4020_MASK = 0x70,
	/* make bnc trig/ext clock threshold 0V instead of 2.5V */
	BNC_TRIG_THRESHOLD_0V_BIT = 0x80,
};

static inline u8 adc_src_4020_bits(unsigned int source)
{
	return (source << 4) & ADC_SRC_4020_MASK;
};

static inline u8 attenuate_bit(unsigned int channel)
{
	/* attenuate channel (+-5V input range) */
	return 1 << (channel & 0x3);
};

/* analog input ranges for 64xx boards */
static const struct comedi_lrange ai_ranges_64xx = {
	8, {
		BIP_RANGE(10),
		BIP_RANGE(5),
		BIP_RANGE(2.5),
		BIP_RANGE(1.25),
		UNI_RANGE(10),
		UNI_RANGE(5),
		UNI_RANGE(2.5),
		UNI_RANGE(1.25)
	}
};

static const u8 ai_range_code_64xx[8] = {
	0x0, 0x1, 0x2, 0x3,	/* bipolar 10, 5, 2,5, 1.25 */
	0x8, 0x9, 0xa, 0xb	/* unipolar 10, 5, 2.5, 1.25 */
};

/* analog input ranges for 64-Mx boards */
static const struct comedi_lrange ai_ranges_64_mx = {
	7, {
		BIP_RANGE(5),
		BIP_RANGE(2.5),
		BIP_RANGE(1.25),
		BIP_RANGE(0.625),
		UNI_RANGE(5),
		UNI_RANGE(2.5),
		UNI_RANGE(1.25)
	}
};

static const u8 ai_range_code_64_mx[7] = {
	0x0, 0x1, 0x2, 0x3,	/* bipolar 5, 2.5, 1.25, 0.625 */
	0x9, 0xa, 0xb		/* unipolar 5, 2.5, 1.25 */
};

/* analog input ranges for 60xx boards */
static const struct comedi_lrange ai_ranges_60xx = {
	4, {
		BIP_RANGE(10),
		BIP_RANGE(5),
		BIP_RANGE(0.5),
		BIP_RANGE(0.05)
	}
};

static const u8 ai_range_code_60xx[4] = {
	0x0, 0x1, 0x4, 0x7	/* bipolar 10, 5, 0.5, 0.05 */
};

/* analog input ranges for 6030, etc boards */
static const struct comedi_lrange ai_ranges_6030 = {
	14, {
		BIP_RANGE(10),
		BIP_RANGE(5),
		BIP_RANGE(2),
		BIP_RANGE(1),
		BIP_RANGE(0.5),
		BIP_RANGE(0.2),
		BIP_RANGE(0.1),
		UNI_RANGE(10),
		UNI_RANGE(5),
		UNI_RANGE(2),
		UNI_RANGE(1),
		UNI_RANGE(0.5),
		UNI_RANGE(0.2),
		UNI_RANGE(0.1)
	}
};

static const u8 ai_range_code_6030[14] = {
	0x0, 0x1, 0x2, 0x3, 0x4, 0x5, 0x6, /* bip 10, 5, 2, 1, 0.5, 0.2, 0.1 */
	0x9, 0xa, 0xb, 0xc, 0xd, 0xe, 0xf  /* uni 10, 5, 2, 1, 0.5, 0.2, 0.1 */
};

/* analog input ranges for 6052, etc boards */
static const struct comedi_lrange ai_ranges_6052 = {
	15, {
		BIP_RANGE(10),
		BIP_RANGE(5),
		BIP_RANGE(2.5),
		BIP_RANGE(1),
		BIP_RANGE(0.5),
		BIP_RANGE(0.25),
		BIP_RANGE(0.1),
		BIP_RANGE(0.05),
		UNI_RANGE(10),
		UNI_RANGE(5),
		UNI_RANGE(2),
		UNI_RANGE(1),
		UNI_RANGE(0.5),
		UNI_RANGE(0.2),
		UNI_RANGE(0.1)
	}
};

static const u8 ai_range_code_6052[15] = {
	0x0, 0x1, 0x2, 0x3, 0x4, 0x5, 0x6, 0x7,	/* bipolar 10 ... 0.05 */
	0x9, 0xa, 0xb, 0xc, 0xd, 0xe, 0xf	/* unipolar 10 ... 0.1 */
};

/* analog input ranges for 4020 board */
static const struct comedi_lrange ai_ranges_4020 = {
	2, {
		BIP_RANGE(5),
		BIP_RANGE(1)
	}
};

/* analog output ranges */
static const struct comedi_lrange ao_ranges_64xx = {
	4, {
		BIP_RANGE(5),
		BIP_RANGE(10),
		UNI_RANGE(5),
		UNI_RANGE(10)
	}
};

static const int ao_range_code_64xx[] = {
	0x0,
	0x1,
	0x2,
	0x3,
};

static const int ao_range_code_60xx[] = {
	0x0,
};

static const struct comedi_lrange ao_ranges_6030 = {
	2, {
		BIP_RANGE(10),
		UNI_RANGE(10)
	}
};

static const int ao_range_code_6030[] = {
	0x0,
	0x2,
};

static const struct comedi_lrange ao_ranges_4020 = {
	2, {
		BIP_RANGE(5),
		BIP_RANGE(10)
	}
};

static const int ao_range_code_4020[] = {
	0x1,
	0x0,
};

enum register_layout {
	LAYOUT_60XX,
	LAYOUT_64XX,
	LAYOUT_4020,
};

struct hw_fifo_info {
	unsigned int num_segments;
	unsigned int max_segment_length;
	unsigned int sample_packing_ratio;
	u16 fifo_size_reg_mask;
};

enum pcidas64_boardid {
	BOARD_PCIDAS6402_16,
	BOARD_PCIDAS6402_12,
	BOARD_PCIDAS64_M1_16,
	BOARD_PCIDAS64_M2_16,
	BOARD_PCIDAS64_M3_16,
	BOARD_PCIDAS6013,
	BOARD_PCIDAS6014,
	BOARD_PCIDAS6023,
	BOARD_PCIDAS6025,
	BOARD_PCIDAS6030,
	BOARD_PCIDAS6031,
	BOARD_PCIDAS6032,
	BOARD_PCIDAS6033,
	BOARD_PCIDAS6034,
	BOARD_PCIDAS6035,
	BOARD_PCIDAS6036,
	BOARD_PCIDAS6040,
	BOARD_PCIDAS6052,
	BOARD_PCIDAS6070,
	BOARD_PCIDAS6071,
	BOARD_PCIDAS4020_12,
	BOARD_PCIDAS6402_16_JR,
	BOARD_PCIDAS64_M1_16_JR,
	BOARD_PCIDAS64_M2_16_JR,
	BOARD_PCIDAS64_M3_16_JR,
	BOARD_PCIDAS64_M1_14,
	BOARD_PCIDAS64_M2_14,
	BOARD_PCIDAS64_M3_14,
};

struct pcidas64_board {
	const char *name;
	int ai_se_chans;	/* number of ai inputs in single-ended mode */
	int ai_bits;		/* analog input resolution */
	int ai_speed;		/* fastest conversion period in ns */
	const struct comedi_lrange *ai_range_table;
	const u8 *ai_range_code;
	int ao_nchan;		/* number of analog out channels */
	int ao_bits;		/* analog output resolution */
	int ao_scan_speed;	/* analog output scan speed */
	const struct comedi_lrange *ao_range_table;
	const int *ao_range_code;
	const struct hw_fifo_info *const ai_fifo;
	/* different board families have slightly different registers */
	enum register_layout layout;
	unsigned has_8255:1;
};

static const struct hw_fifo_info ai_fifo_4020 = {
	.num_segments = 2,
	.max_segment_length = 0x8000,
	.sample_packing_ratio = 2,
	.fifo_size_reg_mask = 0x7f,
};

static const struct hw_fifo_info ai_fifo_64xx = {
	.num_segments = 4,
	.max_segment_length = 0x800,
	.sample_packing_ratio = 1,
	.fifo_size_reg_mask = 0x3f,
};

static const struct hw_fifo_info ai_fifo_60xx = {
	.num_segments = 4,
	.max_segment_length = 0x800,
	.sample_packing_ratio = 1,
	.fifo_size_reg_mask = 0x7f,
};

/*
 * maximum number of dma transfers we will chain together into a ring
 * (and the maximum number of dma buffers we maintain)
 */
#define MAX_AI_DMA_RING_COUNT (0x80000 / DMA_BUFFER_SIZE)
#define MIN_AI_DMA_RING_COUNT (0x10000 / DMA_BUFFER_SIZE)
#define AO_DMA_RING_COUNT (0x10000 / DMA_BUFFER_SIZE)
static inline unsigned int ai_dma_ring_count(const struct pcidas64_board *board)
{
	if (board->layout == LAYOUT_4020)
		return MAX_AI_DMA_RING_COUNT;

	return MIN_AI_DMA_RING_COUNT;
}

static const int bytes_in_sample = 2;

static const struct pcidas64_board pcidas64_boards[] = {
	[BOARD_PCIDAS6402_16] = {
		.name		= "pci-das6402/16",
		.ai_se_chans	= 64,
		.ai_bits	= 16,
		.ai_speed	= 5000,
		.ao_nchan	= 2,
		.ao_bits	= 16,
		.ao_scan_speed	= 10000,
		.layout		= LAYOUT_64XX,
		.ai_range_table	= &ai_ranges_64xx,
		.ai_range_code	= ai_range_code_64xx,
		.ao_range_table	= &ao_ranges_64xx,
		.ao_range_code	= ao_range_code_64xx,
		.ai_fifo	= &ai_fifo_64xx,
		.has_8255	= 1,
	},
	[BOARD_PCIDAS6402_12] = {
		.name		= "pci-das6402/12",	/* XXX check */
		.ai_se_chans	= 64,
		.ai_bits	= 12,
		.ai_speed	= 5000,
		.ao_nchan	= 2,
		.ao_bits	= 12,
		.ao_scan_speed	= 10000,
		.layout		= LAYOUT_64XX,
		.ai_range_table	= &ai_ranges_64xx,
		.ai_range_code	= ai_range_code_64xx,
		.ao_range_table	= &ao_ranges_64xx,
		.ao_range_code	= ao_range_code_64xx,
		.ai_fifo	= &ai_fifo_64xx,
		.has_8255	= 1,
	},
	[BOARD_PCIDAS64_M1_16] = {
		.name		= "pci-das64/m1/16",
		.ai_se_chans	= 64,
		.ai_bits	= 16,
		.ai_speed	= 1000,
		.ao_nchan	= 2,
		.ao_bits	= 16,
		.ao_scan_speed	= 10000,
		.layout		= LAYOUT_64XX,
		.ai_range_table	= &ai_ranges_64_mx,
		.ai_range_code	= ai_range_code_64_mx,
		.ao_range_table	= &ao_ranges_64xx,
		.ao_range_code	= ao_range_code_64xx,
		.ai_fifo	= &ai_fifo_64xx,
		.has_8255	= 1,
	},
	[BOARD_PCIDAS64_M2_16] = {
		.name = "pci-das64/m2/16",
		.ai_se_chans	= 64,
		.ai_bits	= 16,
		.ai_speed	= 500,
		.ao_nchan	= 2,
		.ao_bits	= 16,
		.ao_scan_speed	= 10000,
		.layout		= LAYOUT_64XX,
		.ai_range_table	= &ai_ranges_64_mx,
		.ai_range_code	= ai_range_code_64_mx,
		.ao_range_table	= &ao_ranges_64xx,
		.ao_range_code	= ao_range_code_64xx,
		.ai_fifo	= &ai_fifo_64xx,
		.has_8255	= 1,
	},
	[BOARD_PCIDAS64_M3_16] = {
		.name		= "pci-das64/m3/16",
		.ai_se_chans	= 64,
		.ai_bits	= 16,
		.ai_speed	= 333,
		.ao_nchan	= 2,
		.ao_bits	= 16,
		.ao_scan_speed	= 10000,
		.layout		= LAYOUT_64XX,
		.ai_range_table	= &ai_ranges_64_mx,
		.ai_range_code	= ai_range_code_64_mx,
		.ao_range_table	= &ao_ranges_64xx,
		.ao_range_code	= ao_range_code_64xx,
		.ai_fifo	= &ai_fifo_64xx,
		.has_8255	= 1,
	},
	[BOARD_PCIDAS6013] = {
		.name		= "pci-das6013",
		.ai_se_chans	= 16,
		.ai_bits	= 16,
		.ai_speed	= 5000,
		.ao_nchan	= 0,
		.ao_bits	= 16,
		.layout		= LAYOUT_60XX,
		.ai_range_table	= &ai_ranges_60xx,
		.ai_range_code	= ai_range_code_60xx,
		.ao_range_table	= &range_bipolar10,
		.ao_range_code	= ao_range_code_60xx,
		.ai_fifo	= &ai_fifo_60xx,
		.has_8255	= 0,
	},
	[BOARD_PCIDAS6014] = {
		.name		= "pci-das6014",
		.ai_se_chans	= 16,
		.ai_bits	= 16,
		.ai_speed	= 5000,
		.ao_nchan	= 2,
		.ao_bits	= 16,
		.ao_scan_speed	= 100000,
		.layout		= LAYOUT_60XX,
		.ai_range_table	= &ai_ranges_60xx,
		.ai_range_code	= ai_range_code_60xx,
		.ao_range_table	= &range_bipolar10,
		.ao_range_code	= ao_range_code_60xx,
		.ai_fifo	= &ai_fifo_60xx,
		.has_8255	= 0,
	},
	[BOARD_PCIDAS6023] = {
		.name		= "pci-das6023",
		.ai_se_chans	= 16,
		.ai_bits	= 12,
		.ai_speed	= 5000,
		.ao_nchan	= 0,
		.ao_scan_speed	= 100000,
		.layout		= LAYOUT_60XX,
		.ai_range_table	= &ai_ranges_60xx,
		.ai_range_code	= ai_range_code_60xx,
		.ao_range_table	= &range_bipolar10,
		.ao_range_code	= ao_range_code_60xx,
		.ai_fifo	= &ai_fifo_60xx,
		.has_8255	= 1,
	},
	[BOARD_PCIDAS6025] = {
		.name		= "pci-das6025",
		.ai_se_chans	= 16,
		.ai_bits	= 12,
		.ai_speed	= 5000,
		.ao_nchan	= 2,
		.ao_bits	= 12,
		.ao_scan_speed	= 100000,
		.layout		= LAYOUT_60XX,
		.ai_range_table	= &ai_ranges_60xx,
		.ai_range_code	= ai_range_code_60xx,
		.ao_range_table	= &range_bipolar10,
		.ao_range_code	= ao_range_code_60xx,
		.ai_fifo	= &ai_fifo_60xx,
		.has_8255	= 1,
	},
	[BOARD_PCIDAS6030] = {
		.name		= "pci-das6030",
		.ai_se_chans	= 16,
		.ai_bits	= 16,
		.ai_speed	= 10000,
		.ao_nchan	= 2,
		.ao_bits	= 16,
		.ao_scan_speed	= 10000,
		.layout		= LAYOUT_60XX,
		.ai_range_table	= &ai_ranges_6030,
		.ai_range_code	= ai_range_code_6030,
		.ao_range_table	= &ao_ranges_6030,
		.ao_range_code	= ao_range_code_6030,
		.ai_fifo	= &ai_fifo_60xx,
		.has_8255	= 0,
	},
	[BOARD_PCIDAS6031] = {
		.name		= "pci-das6031",
		.ai_se_chans	= 64,
		.ai_bits	= 16,
		.ai_speed	= 10000,
		.ao_nchan	= 2,
		.ao_bits	= 16,
		.ao_scan_speed	= 10000,
		.layout		= LAYOUT_60XX,
		.ai_range_table	= &ai_ranges_6030,
		.ai_range_code	= ai_range_code_6030,
		.ao_range_table	= &ao_ranges_6030,
		.ao_range_code	= ao_range_code_6030,
		.ai_fifo	= &ai_fifo_60xx,
		.has_8255	= 0,
	},
	[BOARD_PCIDAS6032] = {
		.name		= "pci-das6032",
		.ai_se_chans	= 16,
		.ai_bits	= 16,
		.ai_speed	= 10000,
		.ao_nchan	= 0,
		.layout		= LAYOUT_60XX,
		.ai_range_table	= &ai_ranges_6030,
		.ai_range_code	= ai_range_code_6030,
		.ai_fifo	= &ai_fifo_60xx,
		.has_8255	= 0,
	},
	[BOARD_PCIDAS6033] = {
		.name		= "pci-das6033",
		.ai_se_chans	= 64,
		.ai_bits	= 16,
		.ai_speed	= 10000,
		.ao_nchan	= 0,
		.layout		= LAYOUT_60XX,
		.ai_range_table	= &ai_ranges_6030,
		.ai_range_code	= ai_range_code_6030,
		.ai_fifo	= &ai_fifo_60xx,
		.has_8255	= 0,
	},
	[BOARD_PCIDAS6034] = {
		.name		= "pci-das6034",
		.ai_se_chans	= 16,
		.ai_bits	= 16,
		.ai_speed	= 5000,
		.ao_nchan	= 0,
		.ao_scan_speed	= 0,
		.layout		= LAYOUT_60XX,
		.ai_range_table	= &ai_ranges_60xx,
		.ai_range_code	= ai_range_code_60xx,
		.ai_fifo	= &ai_fifo_60xx,
		.has_8255	= 0,
	},
	[BOARD_PCIDAS6035] = {
		.name		= "pci-das6035",
		.ai_se_chans	= 16,
		.ai_bits	= 16,
		.ai_speed	= 5000,
		.ao_nchan	= 2,
		.ao_bits	= 12,
		.ao_scan_speed	= 100000,
		.layout		= LAYOUT_60XX,
		.ai_range_table	= &ai_ranges_60xx,
		.ai_range_code	= ai_range_code_60xx,
		.ao_range_table	= &range_bipolar10,
		.ao_range_code	= ao_range_code_60xx,
		.ai_fifo	= &ai_fifo_60xx,
		.has_8255	= 0,
	},
	[BOARD_PCIDAS6036] = {
		.name		= "pci-das6036",
		.ai_se_chans	= 16,
		.ai_bits	= 16,
		.ai_speed	= 5000,
		.ao_nchan	= 2,
		.ao_bits	= 16,
		.ao_scan_speed	= 100000,
		.layout		= LAYOUT_60XX,
		.ai_range_table	= &ai_ranges_60xx,
		.ai_range_code	= ai_range_code_60xx,
		.ao_range_table	= &range_bipolar10,
		.ao_range_code	= ao_range_code_60xx,
		.ai_fifo	= &ai_fifo_60xx,
		.has_8255	= 0,
	},
	[BOARD_PCIDAS6040] = {
		.name		= "pci-das6040",
		.ai_se_chans	= 16,
		.ai_bits	= 12,
		.ai_speed	= 2000,
		.ao_nchan	= 2,
		.ao_bits	= 12,
		.ao_scan_speed	= 1000,
		.layout		= LAYOUT_60XX,
		.ai_range_table	= &ai_ranges_6052,
		.ai_range_code	= ai_range_code_6052,
		.ao_range_table	= &ao_ranges_6030,
		.ao_range_code	= ao_range_code_6030,
		.ai_fifo	= &ai_fifo_60xx,
		.has_8255	= 0,
	},
	[BOARD_PCIDAS6052] = {
		.name		= "pci-das6052",
		.ai_se_chans	= 16,
		.ai_bits	= 16,
		.ai_speed	= 3333,
		.ao_nchan	= 2,
		.ao_bits	= 16,
		.ao_scan_speed	= 3333,
		.layout		= LAYOUT_60XX,
		.ai_range_table	= &ai_ranges_6052,
		.ai_range_code	= ai_range_code_6052,
		.ao_range_table	= &ao_ranges_6030,
		.ao_range_code	= ao_range_code_6030,
		.ai_fifo	= &ai_fifo_60xx,
		.has_8255	= 0,
	},
	[BOARD_PCIDAS6070] = {
		.name		= "pci-das6070",
		.ai_se_chans	= 16,
		.ai_bits	= 12,
		.ai_speed	= 800,
		.ao_nchan	= 2,
		.ao_bits	= 12,
		.ao_scan_speed	= 1000,
		.layout		= LAYOUT_60XX,
		.ai_range_table	= &ai_ranges_6052,
		.ai_range_code	= ai_range_code_6052,
		.ao_range_table	= &ao_ranges_6030,
		.ao_range_code	= ao_range_code_6030,
		.ai_fifo	= &ai_fifo_60xx,
		.has_8255	= 0,
	},
	[BOARD_PCIDAS6071] = {
		.name		= "pci-das6071",
		.ai_se_chans	= 64,
		.ai_bits	= 12,
		.ai_speed	= 800,
		.ao_nchan	= 2,
		.ao_bits	= 12,
		.ao_scan_speed	= 1000,
		.layout		= LAYOUT_60XX,
		.ai_range_table	= &ai_ranges_6052,
		.ai_range_code	= ai_range_code_6052,
		.ao_range_table	= &ao_ranges_6030,
		.ao_range_code	= ao_range_code_6030,
		.ai_fifo	= &ai_fifo_60xx,
		.has_8255	= 0,
	},
	[BOARD_PCIDAS4020_12] = {
		.name		= "pci-das4020/12",
		.ai_se_chans	= 4,
		.ai_bits	= 12,
		.ai_speed	= 50,
		.ao_bits	= 12,
		.ao_nchan	= 2,
		.ao_scan_speed	= 0,	/* no hardware pacing on ao */
		.layout		= LAYOUT_4020,
		.ai_range_table	= &ai_ranges_4020,
		.ao_range_table	= &ao_ranges_4020,
		.ao_range_code	= ao_range_code_4020,
		.ai_fifo	= &ai_fifo_4020,
		.has_8255	= 1,
	},
#if 0
	/* The device id for these boards is unknown */

	[BOARD_PCIDAS6402_16_JR] = {
		.name		= "pci-das6402/16/jr",
		.ai_se_chans	= 64,
		.ai_bits	= 16,
		.ai_speed	= 5000,
		.ao_nchan	= 0,
		.ao_scan_speed	= 10000,
		.layout		= LAYOUT_64XX,
		.ai_range_table	= &ai_ranges_64xx,
		.ai_range_code	= ai_range_code_64xx,
		.ai_fifo	= ai_fifo_64xx,
		.has_8255	= 1,
	},
	[BOARD_PCIDAS64_M1_16_JR] = {
		.name		= "pci-das64/m1/16/jr",
		.ai_se_chans	= 64,
		.ai_bits	= 16,
		.ai_speed	= 1000,
		.ao_nchan	= 0,
		.ao_scan_speed	= 10000,
		.layout		= LAYOUT_64XX,
		.ai_range_table	= &ai_ranges_64_mx,
		.ai_range_code	= ai_range_code_64_mx,
		.ai_fifo	= ai_fifo_64xx,
		.has_8255	= 1,
	},
	[BOARD_PCIDAS64_M2_16_JR] = {
		.name = "pci-das64/m2/16/jr",
		.ai_se_chans	= 64,
		.ai_bits	= 16,
		.ai_speed	= 500,
		.ao_nchan	= 0,
		.ao_scan_speed	= 10000,
		.layout		= LAYOUT_64XX,
		.ai_range_table	= &ai_ranges_64_mx,
		.ai_range_code	= ai_range_code_64_mx,
		.ai_fifo	= ai_fifo_64xx,
		.has_8255	= 1,
	},
	[BOARD_PCIDAS64_M3_16_JR] = {
		.name		= "pci-das64/m3/16/jr",
		.ai_se_chans	= 64,
		.ai_bits	= 16,
		.ai_speed	= 333,
		.ao_nchan	= 0,
		.ao_scan_speed	= 10000,
		.layout		= LAYOUT_64XX,
		.ai_range_table	= &ai_ranges_64_mx,
		.ai_range_code	= ai_range_code_64_mx,
		.ai_fifo	= ai_fifo_64xx,
		.has_8255	= 1,
	},
	[BOARD_PCIDAS64_M1_14] = {
		.name		= "pci-das64/m1/14",
		.ai_se_chans	= 64,
		.ai_bits	= 14,
		.ai_speed	= 1000,
		.ao_nchan	= 2,
		.ao_scan_speed	= 10000,
		.layout		= LAYOUT_64XX,
		.ai_range_table	= &ai_ranges_64_mx,
		.ai_range_code	= ai_range_code_64_mx,
		.ai_fifo	= ai_fifo_64xx,
		.has_8255	= 1,
	},
	[BOARD_PCIDAS64_M2_14] = {
		.name		= "pci-das64/m2/14",
		.ai_se_chans	= 64,
		.ai_bits	= 14,
		.ai_speed	= 500,
		.ao_nchan	= 2,
		.ao_scan_speed	= 10000,
		.layout		= LAYOUT_64XX,
		.ai_range_table	= &ai_ranges_64_mx,
		.ai_range_code	= ai_range_code_64_mx,
		.ai_fifo	= ai_fifo_64xx,
		.has_8255	= 1,
	},
	[BOARD_PCIDAS64_M3_14] = {
		.name		= "pci-das64/m3/14",
		.ai_se_chans	= 64,
		.ai_bits	= 14,
		.ai_speed	= 333,
		.ao_nchan	= 2,
		.ao_scan_speed	= 10000,
		.layout		= LAYOUT_64XX,
		.ai_range_table	= &ai_ranges_64_mx,
		.ai_range_code	= ai_range_code_64_mx,
		.ai_fifo	= ai_fifo_64xx,
		.has_8255	= 1,
	},
#endif
};

static inline unsigned short se_diff_bit_6xxx(struct comedi_device *dev,
					      int use_differential)
{
	const struct pcidas64_board *board = dev->board_ptr;

	if ((board->layout == LAYOUT_64XX && !use_differential) ||
	    (board->layout == LAYOUT_60XX && use_differential))
		return ADC_SE_DIFF_BIT;

	return 0;
}

struct ext_clock_info {
	/* master clock divisor to use for scans with external master clock */
	unsigned int divisor;
	/* chanspec for master clock input when used as scan begin src */
	unsigned int chanspec;
};

/* this structure is for data unique to this hardware driver. */
struct pcidas64_private {
	/* base addresses (physical) */
	resource_size_t main_phys_iobase;
	resource_size_t dio_counter_phys_iobase;
	/* base addresses (ioremapped) */
	void __iomem *plx9080_iobase;
	void __iomem *main_iobase;
	/* local address (used by dma controller) */
	u32 local0_iobase;
	u32 local1_iobase;
	/* dma buffers for analog input */
	u16 *ai_buffer[MAX_AI_DMA_RING_COUNT];
	/* physical addresses of ai dma buffers */
	dma_addr_t ai_buffer_bus_addr[MAX_AI_DMA_RING_COUNT];
	/*
	 * array of ai dma descriptors read by plx9080,
	 * allocated to get proper alignment
	 */
	struct plx_dma_desc *ai_dma_desc;
	/* physical address of ai dma descriptor array */
	dma_addr_t ai_dma_desc_bus_addr;
	/*
	 * index of the ai dma descriptor/buffer
	 * that is currently being used
	 */
	unsigned int ai_dma_index;
	/* dma buffers for analog output */
	u16 *ao_buffer[AO_DMA_RING_COUNT];
	/* physical addresses of ao dma buffers */
	dma_addr_t ao_buffer_bus_addr[AO_DMA_RING_COUNT];
	struct plx_dma_desc *ao_dma_desc;
	dma_addr_t ao_dma_desc_bus_addr;
	/* keeps track of buffer where the next ao sample should go */
	unsigned int ao_dma_index;
	unsigned int hw_revision;	/* stc chip hardware revision number */
	/* last bits sent to INTR_ENABLE_REG register */
	unsigned int intr_enable_bits;
	/* last bits sent to ADC_CONTROL1_REG register */
	u16 adc_control1_bits;
	/* last bits sent to FIFO_SIZE_REG register */
	u16 fifo_size_bits;
	/* last bits sent to HW_CONFIG_REG register */
	u16 hw_config_bits;
	u16 dac_control1_bits;
	/* last bits written to plx9080 control register */
	u32 plx_control_bits;
	/* last bits written to plx interrupt control and status register */
	u32 plx_intcsr_bits;
	/* index of calibration source readable through ai ch0 */
	int calibration_source;
	/* bits written to i2c calibration/range register */
	u8 i2c_cal_range_bits;
	/* configure digital triggers to trigger on falling edge */
	unsigned int ext_trig_falling;
	short ai_cmd_running;
	unsigned int ai_fifo_segment_length;
	struct ext_clock_info ext_clock;
	unsigned short ao_bounce_buffer[DAC_FIFO_SIZE];
};

static unsigned int ai_range_bits_6xxx(const struct comedi_device *dev,
				       unsigned int range_index)
{
	const struct pcidas64_board *board = dev->board_ptr;

	return board->ai_range_code[range_index] << 8;
}

static unsigned int hw_revision(const struct comedi_device *dev,
				u16 hw_status_bits)
{
	const struct pcidas64_board *board = dev->board_ptr;

	if (board->layout == LAYOUT_4020)
		return (hw_status_bits >> 13) & 0x7;

	return (hw_status_bits >> 12) & 0xf;
}

static void set_dac_range_bits(struct comedi_device *dev,
			       u16 *bits, unsigned int channel,
			       unsigned int range)
{
	const struct pcidas64_board *board = dev->board_ptr;
	unsigned int code = board->ao_range_code[range];

	if (channel > 1)
		dev_err(dev->class_dev, "bug! bad channel?\n");
	if (code & ~0x3)
		dev_err(dev->class_dev, "bug! bad range code?\n");

	*bits &= ~(0x3 << (2 * channel));
	*bits |= code << (2 * channel);
};

static inline int ao_cmd_is_supported(const struct pcidas64_board *board)
{
	return board->ao_nchan && board->layout != LAYOUT_4020;
}

static void abort_dma(struct comedi_device *dev, unsigned int channel)
{
	struct pcidas64_private *devpriv = dev->private;
	unsigned long flags;

	/* spinlock for plx dma control/status reg */
	spin_lock_irqsave(&dev->spinlock, flags);

	plx9080_abort_dma(devpriv->plx9080_iobase, channel);

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

static void disable_plx_interrupts(struct comedi_device *dev)
{
	struct pcidas64_private *devpriv = dev->private;

	devpriv->plx_intcsr_bits = 0;
	writel(devpriv->plx_intcsr_bits,
	       devpriv->plx9080_iobase + PLX_REG_INTCSR);
}

static void disable_ai_interrupts(struct comedi_device *dev)
{
	struct pcidas64_private *devpriv = dev->private;
	unsigned long flags;

	spin_lock_irqsave(&dev->spinlock, flags);
	devpriv->intr_enable_bits &=
		~EN_ADC_INTR_SRC_BIT & ~EN_ADC_DONE_INTR_BIT &
		~EN_ADC_ACTIVE_INTR_BIT & ~EN_ADC_STOP_INTR_BIT &
		~EN_ADC_OVERRUN_BIT & ~ADC_INTR_SRC_MASK;
	writew(devpriv->intr_enable_bits,
	       devpriv->main_iobase + INTR_ENABLE_REG);
	spin_unlock_irqrestore(&dev->spinlock, flags);
}

static void enable_ai_interrupts(struct comedi_device *dev,
				 const struct comedi_cmd *cmd)
{
	const struct pcidas64_board *board = dev->board_ptr;
	struct pcidas64_private *devpriv = dev->private;
	u32 bits;
	unsigned long flags;

	bits = EN_ADC_OVERRUN_BIT | EN_ADC_DONE_INTR_BIT |
	       EN_ADC_ACTIVE_INTR_BIT | EN_ADC_STOP_INTR_BIT;
	/*
	 * Use pio transfer and interrupt on end of conversion
	 * if CMDF_WAKE_EOS flag is set.
	 */
	if (cmd->flags & CMDF_WAKE_EOS) {
		/* 4020 doesn't support pio transfers except for fifo dregs */
		if (board->layout != LAYOUT_4020)
			bits |= ADC_INTR_EOSCAN_BITS | EN_ADC_INTR_SRC_BIT;
	}
	spin_lock_irqsave(&dev->spinlock, flags);
	devpriv->intr_enable_bits |= bits;
	writew(devpriv->intr_enable_bits,
	       devpriv->main_iobase + INTR_ENABLE_REG);
	spin_unlock_irqrestore(&dev->spinlock, flags);
}

/* initialize plx9080 chip */
static void init_plx9080(struct comedi_device *dev)
{
	const struct pcidas64_board *board = dev->board_ptr;
	struct pcidas64_private *devpriv = dev->private;
	u32 bits;
	void __iomem *plx_iobase = devpriv->plx9080_iobase;

	devpriv->plx_control_bits =
		readl(devpriv->plx9080_iobase + PLX_REG_CNTRL);

#ifdef __BIG_ENDIAN
	bits = PLX_BIGEND_DMA0 | PLX_BIGEND_DMA1;
#else
	bits = 0;
#endif
	writel(bits, devpriv->plx9080_iobase + PLX_REG_BIGEND);

	disable_plx_interrupts(dev);

	abort_dma(dev, 0);
	abort_dma(dev, 1);

	/* configure dma0 mode */
	bits = 0;
	/* enable ready input, not sure if this is necessary */
	bits |= PLX_DMAMODE_READYIEN;
	/* enable bterm, not sure if this is necessary */
	bits |= PLX_DMAMODE_BTERMIEN;
	/* enable dma chaining */
	bits |= PLX_DMAMODE_CHAINEN;
	/*
	 * enable interrupt on dma done
	 * (probably don't need this, since chain never finishes)
	 */
	bits |= PLX_DMAMODE_DONEIEN;
	/*
	 * don't increment local address during transfers
	 * (we are transferring from a fixed fifo register)
	 */
	bits |= PLX_DMAMODE_LACONST;
	/* route dma interrupt to pci bus */
	bits |= PLX_DMAMODE_INTRPCI;
	/* enable demand mode */
	bits |= PLX_DMAMODE_DEMAND;
	/* enable local burst mode */
	bits |= PLX_DMAMODE_BURSTEN;
	/* 4020 uses 32 bit dma */
	if (board->layout == LAYOUT_4020)
		bits |= PLX_DMAMODE_WIDTH_32;
	else				/* localspace0 bus is 16 bits wide */
		bits |= PLX_DMAMODE_WIDTH_16;
	writel(bits, plx_iobase + PLX_REG_DMAMODE1);
	if (ao_cmd_is_supported(board))
		writel(bits, plx_iobase + PLX_REG_DMAMODE0);

	/* enable interrupts on plx 9080 */
	devpriv->plx_intcsr_bits |=
	    PLX_INTCSR_LSEABORTEN | PLX_INTCSR_LSEPARITYEN | PLX_INTCSR_PIEN |
	    PLX_INTCSR_PLIEN | PLX_INTCSR_PABORTIEN | PLX_INTCSR_LIOEN |
	    PLX_INTCSR_DMA0IEN | PLX_INTCSR_DMA1IEN;
	writel(devpriv->plx_intcsr_bits,
	       devpriv->plx9080_iobase + PLX_REG_INTCSR);
}

static void disable_ai_pacing(struct comedi_device *dev)
{
	struct pcidas64_private *devpriv = dev->private;
	unsigned long flags;

	disable_ai_interrupts(dev);

	spin_lock_irqsave(&dev->spinlock, flags);
	devpriv->adc_control1_bits &= ~ADC_SW_GATE_BIT;
	writew(devpriv->adc_control1_bits,
	       devpriv->main_iobase + ADC_CONTROL1_REG);
	spin_unlock_irqrestore(&dev->spinlock, flags);

	/* disable pacing, triggering, etc */
	writew(ADC_DMA_DISABLE_BIT | ADC_SOFT_GATE_BITS | ADC_GATE_LEVEL_BIT,
	       devpriv->main_iobase + ADC_CONTROL0_REG);
}

static int set_ai_fifo_segment_length(struct comedi_device *dev,
				      unsigned int num_entries)
{
	const struct pcidas64_board *board = dev->board_ptr;
	struct pcidas64_private *devpriv = dev->private;
	static const int increment_size = 0x100;
	const struct hw_fifo_info *const fifo = board->ai_fifo;
	unsigned int num_increments;
	u16 bits;

	if (num_entries < increment_size)
		num_entries = increment_size;
	if (num_entries > fifo->max_segment_length)
		num_entries = fifo->max_segment_length;

	/* 1 == 256 entries, 2 == 512 entries, etc */
	num_increments = DIV_ROUND_CLOSEST(num_entries, increment_size);

	bits = (~(num_increments - 1)) & fifo->fifo_size_reg_mask;
	devpriv->fifo_size_bits &= ~fifo->fifo_size_reg_mask;
	devpriv->fifo_size_bits |= bits;
	writew(devpriv->fifo_size_bits,
	       devpriv->main_iobase + FIFO_SIZE_REG);

	devpriv->ai_fifo_segment_length = num_increments * increment_size;

	return devpriv->ai_fifo_segment_length;
}

/*
 * adjusts the size of hardware fifo (which determines block size for dma xfers)
 */
static int set_ai_fifo_size(struct comedi_device *dev, unsigned int num_samples)
{
	const struct pcidas64_board *board = dev->board_ptr;
	unsigned int num_fifo_entries;
	int retval;
	const struct hw_fifo_info *const fifo = board->ai_fifo;

	num_fifo_entries = num_samples / fifo->sample_packing_ratio;

	retval = set_ai_fifo_segment_length(dev,
					    num_fifo_entries /
					    fifo->num_segments);
	if (retval < 0)
		return retval;

	return retval * fifo->num_segments * fifo->sample_packing_ratio;
}

/* query length of fifo */
static unsigned int ai_fifo_size(struct comedi_device *dev)
{
	const struct pcidas64_board *board = dev->board_ptr;
	struct pcidas64_private *devpriv = dev->private;

	return devpriv->ai_fifo_segment_length *
	       board->ai_fifo->num_segments *
	       board->ai_fifo->sample_packing_ratio;
}

static void init_stc_registers(struct comedi_device *dev)
{
	const struct pcidas64_board *board = dev->board_ptr;
	struct pcidas64_private *devpriv = dev->private;
	u16 bits;
	unsigned long flags;

	spin_lock_irqsave(&dev->spinlock, flags);

	/*
	 * bit should be set for 6025,
	 * although docs say boards with <= 16 chans should be cleared XXX
	 */
	if (1)
		devpriv->adc_control1_bits |= ADC_QUEUE_CONFIG_BIT;
	writew(devpriv->adc_control1_bits,
	       devpriv->main_iobase + ADC_CONTROL1_REG);

	/* 6402/16 manual says this register must be initialized to 0xff? */
	writew(0xff, devpriv->main_iobase + ADC_SAMPLE_INTERVAL_UPPER_REG);

	bits = SLOW_DAC_BIT | DMA_CH_SELECT_BIT;
	if (board->layout == LAYOUT_4020)
		bits |= INTERNAL_CLOCK_4020_BITS;
	devpriv->hw_config_bits |= bits;
	writew(devpriv->hw_config_bits,
	       devpriv->main_iobase + HW_CONFIG_REG);

	writew(0, devpriv->main_iobase + DAQ_SYNC_REG);
	writew(0, devpriv->main_iobase + CALIBRATION_REG);

	spin_unlock_irqrestore(&dev->spinlock, flags);

	/* set fifos to maximum size */
	devpriv->fifo_size_bits |= DAC_FIFO_BITS;
	set_ai_fifo_segment_length(dev, board->ai_fifo->max_segment_length);

	devpriv->dac_control1_bits = DAC_OUTPUT_ENABLE_BIT;
	devpriv->intr_enable_bits =
		/* EN_DAC_INTR_SRC_BIT | DAC_INTR_QEMPTY_BITS | */
		EN_DAC_DONE_INTR_BIT | EN_DAC_UNDERRUN_BIT;
	writew(devpriv->intr_enable_bits,
	       devpriv->main_iobase + INTR_ENABLE_REG);

	disable_ai_pacing(dev);
};

static int alloc_and_init_dma_members(struct comedi_device *dev)
{
	const struct pcidas64_board *board = dev->board_ptr;
	struct pci_dev *pcidev = comedi_to_pci_dev(dev);
	struct pcidas64_private *devpriv = dev->private;
	int i;

	/* allocate pci dma buffers */
	for (i = 0; i < ai_dma_ring_count(board); i++) {
		devpriv->ai_buffer[i] =
			dma_alloc_coherent(&pcidev->dev, DMA_BUFFER_SIZE,
					   &devpriv->ai_buffer_bus_addr[i],
					   GFP_KERNEL);
		if (!devpriv->ai_buffer[i])
			return -ENOMEM;
	}
	for (i = 0; i < AO_DMA_RING_COUNT; i++) {
		if (ao_cmd_is_supported(board)) {
			devpriv->ao_buffer[i] =
			    dma_alloc_coherent(&pcidev->dev,
					       DMA_BUFFER_SIZE,
					       &devpriv->ao_buffer_bus_addr[i],
					       GFP_KERNEL);
			if (!devpriv->ao_buffer[i])
				return -ENOMEM;
		}
	}
	/* allocate dma descriptors */
	devpriv->ai_dma_desc =
		dma_alloc_coherent(&pcidev->dev, sizeof(struct plx_dma_desc) *
				   ai_dma_ring_count(board),
				   &devpriv->ai_dma_desc_bus_addr, GFP_KERNEL);
	if (!devpriv->ai_dma_desc)
		return -ENOMEM;

	if (ao_cmd_is_supported(board)) {
		devpriv->ao_dma_desc =
			dma_alloc_coherent(&pcidev->dev,
					   sizeof(struct plx_dma_desc) *
					   AO_DMA_RING_COUNT,
					   &devpriv->ao_dma_desc_bus_addr,
					   GFP_KERNEL);
		if (!devpriv->ao_dma_desc)
			return -ENOMEM;
	}
	/* initialize dma descriptors */
	for (i = 0; i < ai_dma_ring_count(board); i++) {
		devpriv->ai_dma_desc[i].pci_start_addr =
			cpu_to_le32(devpriv->ai_buffer_bus_addr[i]);
		if (board->layout == LAYOUT_4020)
			devpriv->ai_dma_desc[i].local_start_addr =
				cpu_to_le32(devpriv->local1_iobase +
					    ADC_FIFO_REG);
		else
			devpriv->ai_dma_desc[i].local_start_addr =
				cpu_to_le32(devpriv->local0_iobase +
					    ADC_FIFO_REG);
		devpriv->ai_dma_desc[i].transfer_size = cpu_to_le32(0);
		devpriv->ai_dma_desc[i].next =
			cpu_to_le32((devpriv->ai_dma_desc_bus_addr +
				     ((i + 1) % ai_dma_ring_count(board)) *
				     sizeof(devpriv->ai_dma_desc[0])) |
				    PLX_DMADPR_DESCPCI | PLX_DMADPR_TCINTR |
				    PLX_DMADPR_XFERL2P);
	}
	if (ao_cmd_is_supported(board)) {
		for (i = 0; i < AO_DMA_RING_COUNT; i++) {
			devpriv->ao_dma_desc[i].pci_start_addr =
				cpu_to_le32(devpriv->ao_buffer_bus_addr[i]);
			devpriv->ao_dma_desc[i].local_start_addr =
				cpu_to_le32(devpriv->local0_iobase +
					    DAC_FIFO_REG);
			devpriv->ao_dma_desc[i].transfer_size = cpu_to_le32(0);
			devpriv->ao_dma_desc[i].next =
				cpu_to_le32((devpriv->ao_dma_desc_bus_addr +
					     ((i + 1) % (AO_DMA_RING_COUNT)) *
					     sizeof(devpriv->ao_dma_desc[0])) |
					    PLX_DMADPR_DESCPCI |
					    PLX_DMADPR_TCINTR);
		}
	}
	return 0;
}

static void cb_pcidas64_free_dma(struct comedi_device *dev)
{
	const struct pcidas64_board *board = dev->board_ptr;
	struct pci_dev *pcidev = comedi_to_pci_dev(dev);
	struct pcidas64_private *devpriv = dev->private;
	int i;

	if (!devpriv)
		return;

	/* free pci dma buffers */
	for (i = 0; i < ai_dma_ring_count(board); i++) {
		if (devpriv->ai_buffer[i])
			dma_free_coherent(&pcidev->dev,
					  DMA_BUFFER_SIZE,
					  devpriv->ai_buffer[i],
					  devpriv->ai_buffer_bus_addr[i]);
	}
	for (i = 0; i < AO_DMA_RING_COUNT; i++) {
		if (devpriv->ao_buffer[i])
			dma_free_coherent(&pcidev->dev,
					  DMA_BUFFER_SIZE,
					  devpriv->ao_buffer[i],
					  devpriv->ao_buffer_bus_addr[i]);
	}
	/* free dma descriptors */
	if (devpriv->ai_dma_desc)
		dma_free_coherent(&pcidev->dev,
				  sizeof(struct plx_dma_desc) *
				  ai_dma_ring_count(board),
				  devpriv->ai_dma_desc,
				  devpriv->ai_dma_desc_bus_addr);
	if (devpriv->ao_dma_desc)
		dma_free_coherent(&pcidev->dev,
				  sizeof(struct plx_dma_desc) *
				  AO_DMA_RING_COUNT,
				  devpriv->ao_dma_desc,
				  devpriv->ao_dma_desc_bus_addr);
}

static inline void warn_external_queue(struct comedi_device *dev)
{
	dev_err(dev->class_dev,
		"AO command and AI external channel queue cannot be used simultaneously\n");
	dev_err(dev->class_dev,
		"Use internal AI channel queue (channels must be consecutive and use same range/aref)\n");
}

/*
 * their i2c requires a huge delay on setting clock or data high for some reason
 */
static const int i2c_high_udelay = 1000;
static const int i2c_low_udelay = 10;

/* set i2c data line high or low */
static void i2c_set_sda(struct comedi_device *dev, int state)
{
	struct pcidas64_private *devpriv = dev->private;
	static const int data_bit = PLX_CNTRL_EEWB;
	void __iomem *plx_control_addr = devpriv->plx9080_iobase +
					 PLX_REG_CNTRL;

	if (state) {				/* set data line high */
		devpriv->plx_control_bits &= ~data_bit;
		writel(devpriv->plx_control_bits, plx_control_addr);
		udelay(i2c_high_udelay);
	} else {				/* set data line low */
		devpriv->plx_control_bits |= data_bit;
		writel(devpriv->plx_control_bits, plx_control_addr);
		udelay(i2c_low_udelay);
	}
}

/* set i2c clock line high or low */
static void i2c_set_scl(struct comedi_device *dev, int state)
{
	struct pcidas64_private *devpriv = dev->private;
	static const int clock_bit = PLX_CNTRL_USERO;
	void __iomem *plx_control_addr = devpriv->plx9080_iobase +
					 PLX_REG_CNTRL;

	if (state) {				/* set clock line high */
		devpriv->plx_control_bits &= ~clock_bit;
		writel(devpriv->plx_control_bits, plx_control_addr);
		udelay(i2c_high_udelay);
	} else {				/* set clock line low */
		devpriv->plx_control_bits |= clock_bit;
		writel(devpriv->plx_control_bits, plx_control_addr);
		udelay(i2c_low_udelay);
	}
}

static void i2c_write_byte(struct comedi_device *dev, u8 byte)
{
	u8 bit;
	unsigned int num_bits = 8;

	for (bit = 1 << (num_bits - 1); bit; bit >>= 1) {
		i2c_set_scl(dev, 0);
		if ((byte & bit))
			i2c_set_sda(dev, 1);
		else
			i2c_set_sda(dev, 0);
		i2c_set_scl(dev, 1);
	}
}

/* we can't really read the lines, so fake it */
static int i2c_read_ack(struct comedi_device *dev)
{
	i2c_set_scl(dev, 0);
	i2c_set_sda(dev, 1);
	i2c_set_scl(dev, 1);

	return 0;		/* return fake acknowledge bit */
}

/* send start bit */
static void i2c_start(struct comedi_device *dev)
{
	i2c_set_scl(dev, 1);
	i2c_set_sda(dev, 1);
	i2c_set_sda(dev, 0);
}

/* send stop bit */
static void i2c_stop(struct comedi_device *dev)
{
	i2c_set_scl(dev, 0);
	i2c_set_sda(dev, 0);
	i2c_set_scl(dev, 1);
	i2c_set_sda(dev, 1);
}

static void i2c_write(struct comedi_device *dev, unsigned int address,
		      const u8 *data, unsigned int length)
{
	struct pcidas64_private *devpriv = dev->private;
	unsigned int i;
	u8 bitstream;
	static const int read_bit = 0x1;

	/*
	 * XXX need mutex to prevent simultaneous attempts to access
	 * eeprom and i2c bus
	 */

	/* make sure we don't send anything to eeprom */
	devpriv->plx_control_bits &= ~PLX_CNTRL_EECS;

	i2c_stop(dev);
	i2c_start(dev);

	/* send address and write bit */
	bitstream = (address << 1) & ~read_bit;
	i2c_write_byte(dev, bitstream);

	/* get acknowledge */
	if (i2c_read_ack(dev) != 0) {
		dev_err(dev->class_dev, "failed: no acknowledge\n");
		i2c_stop(dev);
		return;
	}
	/* write data bytes */
	for (i = 0; i < length; i++) {
		i2c_write_byte(dev, data[i]);
		if (i2c_read_ack(dev) != 0) {
			dev_err(dev->class_dev, "failed: no acknowledge\n");
			i2c_stop(dev);
			return;
		}
	}
	i2c_stop(dev);
}

static int cb_pcidas64_ai_eoc(struct comedi_device *dev,
			      struct comedi_subdevice *s,
			      struct comedi_insn *insn,
			      unsigned long context)
{
	const struct pcidas64_board *board = dev->board_ptr;
	struct pcidas64_private *devpriv = dev->private;
	unsigned int status;

	status = readw(devpriv->main_iobase + HW_STATUS_REG);
	if (board->layout == LAYOUT_4020) {
		status = readw(devpriv->main_iobase + ADC_WRITE_PNTR_REG);
		if (status)
			return 0;
	} else {
		if (pipe_full_bits(status))
			return 0;
	}
	return -EBUSY;
}

static int ai_rinsn(struct comedi_device *dev, struct comedi_subdevice *s,
		    struct comedi_insn *insn, unsigned int *data)
{
	const struct pcidas64_board *board = dev->board_ptr;
	struct pcidas64_private *devpriv = dev->private;
	unsigned int bits = 0, n;
	unsigned int channel, range, aref;
	unsigned long flags;
	int ret;

	channel = CR_CHAN(insn->chanspec);
	range = CR_RANGE(insn->chanspec);
	aref = CR_AREF(insn->chanspec);

	/* disable card's analog input interrupt sources and pacing */
	/* 4020 generates dac done interrupts even though they are disabled */
	disable_ai_pacing(dev);

	spin_lock_irqsave(&dev->spinlock, flags);
	if (insn->chanspec & CR_ALT_FILTER)
		devpriv->adc_control1_bits |= ADC_DITHER_BIT;
	else
		devpriv->adc_control1_bits &= ~ADC_DITHER_BIT;
	writew(devpriv->adc_control1_bits,
	       devpriv->main_iobase + ADC_CONTROL1_REG);
	spin_unlock_irqrestore(&dev->spinlock, flags);

	if (board->layout != LAYOUT_4020) {
		/* use internal queue */
		devpriv->hw_config_bits &= ~EXT_QUEUE_BIT;
		writew(devpriv->hw_config_bits,
		       devpriv->main_iobase + HW_CONFIG_REG);

		/* ALT_SOURCE is internal calibration reference */
		if (insn->chanspec & CR_ALT_SOURCE) {
			unsigned int cal_en_bit;

			if (board->layout == LAYOUT_60XX)
				cal_en_bit = CAL_EN_60XX_BIT;
			else
				cal_en_bit = CAL_EN_64XX_BIT;
			/*
			 * select internal reference source to connect
			 * to channel 0
			 */
			writew(cal_en_bit |
			       adc_src_bits(devpriv->calibration_source),
			       devpriv->main_iobase + CALIBRATION_REG);
		} else {
			/*
			 * make sure internal calibration source
			 * is turned off
			 */
			writew(0, devpriv->main_iobase + CALIBRATION_REG);
		}
		/* load internal queue */
		bits = 0;
		/* set gain */
		bits |= ai_range_bits_6xxx(dev, CR_RANGE(insn->chanspec));
		/* set single-ended / differential */
		bits |= se_diff_bit_6xxx(dev, aref == AREF_DIFF);
		if (aref == AREF_COMMON)
			bits |= ADC_COMMON_BIT;
		bits |= adc_chan_bits(channel);
		/* set stop channel */
		writew(adc_chan_bits(channel),
		       devpriv->main_iobase + ADC_QUEUE_HIGH_REG);
		/* set start channel, and rest of settings */
		writew(bits, devpriv->main_iobase + ADC_QUEUE_LOAD_REG);
	} else {
		u8 old_cal_range_bits = devpriv->i2c_cal_range_bits;

		devpriv->i2c_cal_range_bits &= ~ADC_SRC_4020_MASK;
		if (insn->chanspec & CR_ALT_SOURCE) {
			devpriv->i2c_cal_range_bits |=
				adc_src_4020_bits(devpriv->calibration_source);
		} else {	/* select BNC inputs */
			devpriv->i2c_cal_range_bits |= adc_src_4020_bits(4);
		}
		/* select range */
		if (range == 0)
			devpriv->i2c_cal_range_bits |= attenuate_bit(channel);
		else
			devpriv->i2c_cal_range_bits &= ~attenuate_bit(channel);
		/*
		 * update calibration/range i2c register only if necessary,
		 * as it is very slow
		 */
		if (old_cal_range_bits != devpriv->i2c_cal_range_bits) {
			u8 i2c_data = devpriv->i2c_cal_range_bits;

			i2c_write(dev, RANGE_CAL_I2C_ADDR, &i2c_data,
				  sizeof(i2c_data));
		}

		/*
		 * 4020 manual asks that sample interval register to be set
		 * before writing to convert register.
		 * Using somewhat arbitrary setting of 4 master clock ticks
		 * = 0.1 usec
		 */
		writew(0, devpriv->main_iobase + ADC_SAMPLE_INTERVAL_UPPER_REG);
		writew(2, devpriv->main_iobase + ADC_SAMPLE_INTERVAL_LOWER_REG);
	}

	for (n = 0; n < insn->n; n++) {
		/* clear adc buffer (inside loop for 4020 sake) */
		writew(0, devpriv->main_iobase + ADC_BUFFER_CLEAR_REG);

		/* trigger conversion, bits sent only matter for 4020 */
		writew(adc_convert_chan_4020_bits(CR_CHAN(insn->chanspec)),
		       devpriv->main_iobase + ADC_CONVERT_REG);

		/* wait for data */
		ret = comedi_timeout(dev, s, insn, cb_pcidas64_ai_eoc, 0);
		if (ret)
			return ret;

		if (board->layout == LAYOUT_4020)
			data[n] = readl(dev->mmio + ADC_FIFO_REG) & 0xffff;
		else
			data[n] = readw(devpriv->main_iobase + PIPE1_READ_REG);
	}

	return n;
}

static int ai_config_calibration_source(struct comedi_device *dev,
					unsigned int *data)
{
	const struct pcidas64_board *board = dev->board_ptr;
	struct pcidas64_private *devpriv = dev->private;
	unsigned int source = data[1];
	int num_calibration_sources;

	if (board->layout == LAYOUT_60XX)
		num_calibration_sources = 16;
	else
		num_calibration_sources = 8;
	if (source >= num_calibration_sources) {
		dev_dbg(dev->class_dev, "invalid calibration source: %i\n",
			source);
		return -EINVAL;
	}

	devpriv->calibration_source = source;

	return 2;
}

static int ai_config_block_size(struct comedi_device *dev, unsigned int *data)
{
	const struct pcidas64_board *board = dev->board_ptr;
	int fifo_size;
	const struct hw_fifo_info *const fifo = board->ai_fifo;
	unsigned int block_size, requested_block_size;
	int retval;

	requested_block_size = data[1];

	if (requested_block_size) {
		fifo_size = requested_block_size * fifo->num_segments /
			    bytes_in_sample;

		retval = set_ai_fifo_size(dev, fifo_size);
		if (retval < 0)
			return retval;
	}

	block_size = ai_fifo_size(dev) / fifo->num_segments * bytes_in_sample;

	data[1] = block_size;

	return 2;
}

static int ai_config_master_clock_4020(struct comedi_device *dev,
				       unsigned int *data)
{
	struct pcidas64_private *devpriv = dev->private;
	unsigned int divisor = data[4];
	int retval = 0;

	if (divisor < 2) {
		divisor = 2;
		retval = -EAGAIN;
	}

	switch (data[1]) {
	case COMEDI_EV_SCAN_BEGIN:
		devpriv->ext_clock.divisor = divisor;
		devpriv->ext_clock.chanspec = data[2];
		break;
	default:
		return -EINVAL;
	}

	data[4] = divisor;

	return retval ? retval : 5;
}

/* XXX could add support for 60xx series */
static int ai_config_master_clock(struct comedi_device *dev, unsigned int *data)
{
	const struct pcidas64_board *board = dev->board_ptr;

	switch (board->layout) {
	case LAYOUT_4020:
		return ai_config_master_clock_4020(dev, data);
	default:
		return -EINVAL;
	}

	return -EINVAL;
}

static int ai_config_insn(struct comedi_device *dev, struct comedi_subdevice *s,
			  struct comedi_insn *insn, unsigned int *data)
{
	int id = data[0];

	switch (id) {
	case INSN_CONFIG_ALT_SOURCE:
		return ai_config_calibration_source(dev, data);
	case INSN_CONFIG_BLOCK_SIZE:
		return ai_config_block_size(dev, data);
	case INSN_CONFIG_TIMER_1:
		return ai_config_master_clock(dev, data);
	default:
		return -EINVAL;
	}
	return -EINVAL;
}

/*
 * Gets nearest achievable timing given master clock speed, does not
 * take into account possible minimum/maximum divisor values.  Used
 * by other timing checking functions.
 */
static unsigned int get_divisor(unsigned int ns, unsigned int flags)
{
	unsigned int divisor;

	switch (flags & CMDF_ROUND_MASK) {
	case CMDF_ROUND_UP:
		divisor = DIV_ROUND_UP(ns, TIMER_BASE);
		break;
	case CMDF_ROUND_DOWN:
		divisor = ns / TIMER_BASE;
		break;
	case CMDF_ROUND_NEAREST:
	default:
		divisor = DIV_ROUND_CLOSEST(ns, TIMER_BASE);
		break;
	}
	return divisor;
}

/*
 * utility function that rounds desired timing to an achievable time, and
 * sets cmd members appropriately.
 * adc paces conversions from master clock by dividing by (x + 3) where x is
 * 24 bit number
 */
static void check_adc_timing(struct comedi_device *dev, struct comedi_cmd *cmd)
{
	const struct pcidas64_board *board = dev->board_ptr;
	unsigned long long convert_divisor = 0;
	unsigned int scan_divisor;
	static const int min_convert_divisor = 3;
	static const int max_convert_divisor =
		max_counter_value + min_convert_divisor;
	static const int min_scan_divisor_4020 = 2;
	unsigned long long max_scan_divisor, min_scan_divisor;

	if (cmd->convert_src == TRIG_TIMER) {
		if (board->layout == LAYOUT_4020) {
			cmd->convert_arg = 0;
		} else {
			convert_divisor = get_divisor(cmd->convert_arg,
						      cmd->flags);
			if (convert_divisor > max_convert_divisor)
				convert_divisor = max_convert_divisor;
			if (convert_divisor < min_convert_divisor)
				convert_divisor = min_convert_divisor;
			cmd->convert_arg = convert_divisor * TIMER_BASE;
		}
	} else if (cmd->convert_src == TRIG_NOW) {
		cmd->convert_arg = 0;
	}

	if (cmd->scan_begin_src == TRIG_TIMER) {
		scan_divisor = get_divisor(cmd->scan_begin_arg, cmd->flags);
		if (cmd->convert_src == TRIG_TIMER) {
			min_scan_divisor = convert_divisor * cmd->chanlist_len;
			max_scan_divisor =
				(convert_divisor * cmd->chanlist_len - 1) +
				max_counter_value;
		} else {
			min_scan_divisor = min_scan_divisor_4020;
			max_scan_divisor = max_counter_value + min_scan_divisor;
		}
		if (scan_divisor > max_scan_divisor)
			scan_divisor = max_scan_divisor;
		if (scan_divisor < min_scan_divisor)
			scan_divisor = min_scan_divisor;
		cmd->scan_begin_arg = scan_divisor * TIMER_BASE;
	}
}

static int cb_pcidas64_ai_check_chanlist(struct comedi_device *dev,
					 struct comedi_subdevice *s,
					 struct comedi_cmd *cmd)
{
	const struct pcidas64_board *board = dev->board_ptr;
	unsigned int aref0 = CR_AREF(cmd->chanlist[0]);
	int i;

	for (i = 1; i < cmd->chanlist_len; i++) {
		unsigned int aref = CR_AREF(cmd->chanlist[i]);

		if (aref != aref0) {
			dev_dbg(dev->class_dev,
				"all elements in chanlist must use the same analog reference\n");
			return -EINVAL;
		}
	}

	if (board->layout == LAYOUT_4020) {
		unsigned int chan0 = CR_CHAN(cmd->chanlist[0]);

		for (i = 1; i < cmd->chanlist_len; i++) {
			unsigned int chan = CR_CHAN(cmd->chanlist[i]);

			if (chan != (chan0 + i)) {
				dev_dbg(dev->class_dev,
					"chanlist must use consecutive channels\n");
				return -EINVAL;
			}
		}
		if (cmd->chanlist_len == 3) {
			dev_dbg(dev->class_dev,
				"chanlist cannot be 3 channels long, use 1, 2, or 4 channels\n");
			return -EINVAL;
		}
	}

	return 0;
}

static int ai_cmdtest(struct comedi_device *dev, struct comedi_subdevice *s,
		      struct comedi_cmd *cmd)
{
	const struct pcidas64_board *board = dev->board_ptr;
	int err = 0;
	unsigned int tmp_arg, tmp_arg2;
	unsigned int triggers;

	/* Step 1 : check if triggers are trivially valid */

	err |= comedi_check_trigger_src(&cmd->start_src, TRIG_NOW | TRIG_EXT);

	triggers = TRIG_TIMER;
	if (board->layout == LAYOUT_4020)
		triggers |= TRIG_OTHER;
	else
		triggers |= TRIG_FOLLOW;
	err |= comedi_check_trigger_src(&cmd->scan_begin_src, triggers);

	triggers = TRIG_TIMER;
	if (board->layout == LAYOUT_4020)
		triggers |= TRIG_NOW;
	else
		triggers |= TRIG_EXT;
	err |= comedi_check_trigger_src(&cmd->convert_src, triggers);
	err |= comedi_check_trigger_src(&cmd->scan_end_src, TRIG_COUNT);
	err |= comedi_check_trigger_src(&cmd->stop_src,
					TRIG_COUNT | TRIG_EXT | TRIG_NONE);

	if (err)
		return 1;

	/* Step 2a : make sure trigger sources are unique */

	err |= comedi_check_trigger_is_unique(cmd->start_src);
	err |= comedi_check_trigger_is_unique(cmd->scan_begin_src);
	err |= comedi_check_trigger_is_unique(cmd->convert_src);
	err |= comedi_check_trigger_is_unique(cmd->stop_src);

	/* Step 2b : and mutually compatible */

	if (cmd->convert_src == TRIG_EXT && cmd->scan_begin_src == TRIG_TIMER)
		err |= -EINVAL;

	if (err)
		return 2;

	/* Step 3: check if arguments are trivially valid */

	switch (cmd->start_src) {
	case TRIG_NOW:
		err |= comedi_check_trigger_arg_is(&cmd->start_arg, 0);
		break;
	case TRIG_EXT:
		/*
		 * start_arg is the CR_CHAN | CR_INVERT of the
		 * external trigger.
		 */
		break;
	}

	if (cmd->convert_src == TRIG_TIMER) {
		if (board->layout == LAYOUT_4020) {
			err |= comedi_check_trigger_arg_is(&cmd->convert_arg,
							   0);
		} else {
			err |= comedi_check_trigger_arg_min(&cmd->convert_arg,
							    board->ai_speed);
			/*
			 * if scans are timed faster than conversion rate
			 * allows
			 */
			if (cmd->scan_begin_src == TRIG_TIMER) {
				err |= comedi_check_trigger_arg_min(
						&cmd->scan_begin_arg,
						cmd->convert_arg *
						cmd->chanlist_len);
			}
		}
	}

	err |= comedi_check_trigger_arg_min(&cmd->chanlist_len, 1);
	err |= comedi_check_trigger_arg_is(&cmd->scan_end_arg,
					   cmd->chanlist_len);

	switch (cmd->stop_src) {
	case TRIG_EXT:
		break;
	case TRIG_COUNT:
		err |= comedi_check_trigger_arg_min(&cmd->stop_arg, 1);
		break;
	case TRIG_NONE:
		err |= comedi_check_trigger_arg_is(&cmd->stop_arg, 0);
		break;
	default:
		break;
	}

	if (err)
		return 3;

	/* step 4: fix up any arguments */

	if (cmd->convert_src == TRIG_TIMER) {
		tmp_arg = cmd->convert_arg;
		tmp_arg2 = cmd->scan_begin_arg;
		check_adc_timing(dev, cmd);
		if (tmp_arg != cmd->convert_arg)
			err++;
		if (tmp_arg2 != cmd->scan_begin_arg)
			err++;
	}

	if (err)
		return 4;

	/* Step 5: check channel list if it exists */
	if (cmd->chanlist && cmd->chanlist_len > 0)
		err |= cb_pcidas64_ai_check_chanlist(dev, s, cmd);

	if (err)
		return 5;

	return 0;
}

static int use_hw_sample_counter(struct comedi_cmd *cmd)
{
/* disable for now until I work out a race */
	return 0;

	if (cmd->stop_src == TRIG_COUNT && cmd->stop_arg <= max_counter_value)
		return 1;

	return 0;
}

static void setup_sample_counters(struct comedi_device *dev,
				  struct comedi_cmd *cmd)
{
	struct pcidas64_private *devpriv = dev->private;

	/* load hardware conversion counter */
	if (use_hw_sample_counter(cmd)) {
		writew(cmd->stop_arg & 0xffff,
		       devpriv->main_iobase + ADC_COUNT_LOWER_REG);
		writew((cmd->stop_arg >> 16) & 0xff,
		       devpriv->main_iobase + ADC_COUNT_UPPER_REG);
	} else {
		writew(1, devpriv->main_iobase + ADC_COUNT_LOWER_REG);
	}
}

static inline unsigned int dma_transfer_size(struct comedi_device *dev)
{
	const struct pcidas64_board *board = dev->board_ptr;
	struct pcidas64_private *devpriv = dev->private;
	unsigned int num_samples;

	num_samples = devpriv->ai_fifo_segment_length *
		      board->ai_fifo->sample_packing_ratio;
	if (num_samples > DMA_BUFFER_SIZE / sizeof(u16))
		num_samples = DMA_BUFFER_SIZE / sizeof(u16);

	return num_samples;
}

static u32 ai_convert_counter_6xxx(const struct comedi_device *dev,
				   const struct comedi_cmd *cmd)
{
	/* supposed to load counter with desired divisor minus 3 */
	return cmd->convert_arg / TIMER_BASE - 3;
}

static u32 ai_scan_counter_6xxx(struct comedi_device *dev,
				struct comedi_cmd *cmd)
{
	u32 count;

	/* figure out how long we need to delay at end of scan */
	switch (cmd->scan_begin_src) {
	case TRIG_TIMER:
		count = (cmd->scan_begin_arg -
			 (cmd->convert_arg * (cmd->chanlist_len - 1))) /
			TIMER_BASE;
		break;
	case TRIG_FOLLOW:
		count = cmd->convert_arg / TIMER_BASE;
		break;
	default:
		return 0;
	}
	return count - 3;
}

static u32 ai_convert_counter_4020(struct comedi_device *dev,
				   struct comedi_cmd *cmd)
{
	struct pcidas64_private *devpriv = dev->private;
	unsigned int divisor;

	switch (cmd->scan_begin_src) {
	case TRIG_TIMER:
		divisor = cmd->scan_begin_arg / TIMER_BASE;
		break;
	case TRIG_OTHER:
		divisor = devpriv->ext_clock.divisor;
		break;
	default:		/* should never happen */
		dev_err(dev->class_dev, "bug! failed to set ai pacing!\n");
		divisor = 1000;
		break;
	}

	/* supposed to load counter with desired divisor minus 2 for 4020 */
	return divisor - 2;
}

static void select_master_clock_4020(struct comedi_device *dev,
				     const struct comedi_cmd *cmd)
{
	struct pcidas64_private *devpriv = dev->private;

	/* select internal/external master clock */
	devpriv->hw_config_bits &= ~MASTER_CLOCK_4020_MASK;
	if (cmd->scan_begin_src == TRIG_OTHER) {
		int chanspec = devpriv->ext_clock.chanspec;

		if (CR_CHAN(chanspec))
			devpriv->hw_config_bits |= BNC_CLOCK_4020_BITS;
		else
			devpriv->hw_config_bits |= EXT_CLOCK_4020_BITS;
	} else {
		devpriv->hw_config_bits |= INTERNAL_CLOCK_4020_BITS;
	}
	writew(devpriv->hw_config_bits,
	       devpriv->main_iobase + HW_CONFIG_REG);
}

static void select_master_clock(struct comedi_device *dev,
				const struct comedi_cmd *cmd)
{
	const struct pcidas64_board *board = dev->board_ptr;

	switch (board->layout) {
	case LAYOUT_4020:
		select_master_clock_4020(dev, cmd);
		break;
	default:
		break;
	}
}

static inline void dma_start_sync(struct comedi_device *dev,
				  unsigned int channel)
{
	struct pcidas64_private *devpriv = dev->private;
	unsigned long flags;

	/* spinlock for plx dma control/status reg */
	spin_lock_irqsave(&dev->spinlock, flags);
	writeb(PLX_DMACSR_ENABLE | PLX_DMACSR_START | PLX_DMACSR_CLEARINTR,
	       devpriv->plx9080_iobase + PLX_REG_DMACSR(channel));
	spin_unlock_irqrestore(&dev->spinlock, flags);
}

static void set_ai_pacing(struct comedi_device *dev, struct comedi_cmd *cmd)
{
	const struct pcidas64_board *board = dev->board_ptr;
	struct pcidas64_private *devpriv = dev->private;
	u32 convert_counter = 0, scan_counter = 0;

	check_adc_timing(dev, cmd);

	select_master_clock(dev, cmd);

	if (board->layout == LAYOUT_4020) {
		convert_counter = ai_convert_counter_4020(dev, cmd);
	} else {
		convert_counter = ai_convert_counter_6xxx(dev, cmd);
		scan_counter = ai_scan_counter_6xxx(dev, cmd);
	}

	/* load lower 16 bits of convert interval */
	writew(convert_counter & 0xffff,
	       devpriv->main_iobase + ADC_SAMPLE_INTERVAL_LOWER_REG);
	/* load upper 8 bits of convert interval */
	writew((convert_counter >> 16) & 0xff,
	       devpriv->main_iobase + ADC_SAMPLE_INTERVAL_UPPER_REG);
	/* load lower 16 bits of scan delay */
	writew(scan_counter & 0xffff,
	       devpriv->main_iobase + ADC_DELAY_INTERVAL_LOWER_REG);
	/* load upper 8 bits of scan delay */
	writew((scan_counter >> 16) & 0xff,
	       devpriv->main_iobase + ADC_DELAY_INTERVAL_UPPER_REG);
}

static int use_internal_queue_6xxx(const struct comedi_cmd *cmd)
{
	int i;

	for (i = 0; i + 1 < cmd->chanlist_len; i++) {
		if (CR_CHAN(cmd->chanlist[i + 1]) !=
		    CR_CHAN(cmd->chanlist[i]) + 1)
			return 0;
		if (CR_RANGE(cmd->chanlist[i + 1]) !=
		    CR_RANGE(cmd->chanlist[i]))
			return 0;
		if (CR_AREF(cmd->chanlist[i + 1]) != CR_AREF(cmd->chanlist[i]))
			return 0;
	}
	return 1;
}

static int setup_channel_queue(struct comedi_device *dev,
			       const struct comedi_cmd *cmd)
{
	const struct pcidas64_board *board = dev->board_ptr;
	struct pcidas64_private *devpriv = dev->private;
	unsigned short bits;
	int i;

	if (board->layout != LAYOUT_4020) {
		if (use_internal_queue_6xxx(cmd)) {
			devpriv->hw_config_bits &= ~EXT_QUEUE_BIT;
			writew(devpriv->hw_config_bits,
			       devpriv->main_iobase + HW_CONFIG_REG);
			bits = 0;
			/* set channel */
			bits |= adc_chan_bits(CR_CHAN(cmd->chanlist[0]));
			/* set gain */
			bits |= ai_range_bits_6xxx(dev,
						   CR_RANGE(cmd->chanlist[0]));
			/* set single-ended / differential */
			bits |= se_diff_bit_6xxx(dev,
						 CR_AREF(cmd->chanlist[0]) ==
						 AREF_DIFF);
			if (CR_AREF(cmd->chanlist[0]) == AREF_COMMON)
				bits |= ADC_COMMON_BIT;
			/* set stop channel */
			writew(adc_chan_bits
			       (CR_CHAN(cmd->chanlist[cmd->chanlist_len - 1])),
			       devpriv->main_iobase + ADC_QUEUE_HIGH_REG);
			/* set start channel, and rest of settings */
			writew(bits,
			       devpriv->main_iobase + ADC_QUEUE_LOAD_REG);
		} else {
			/* use external queue */
			if (dev->write_subdev && dev->write_subdev->busy) {
				warn_external_queue(dev);
				return -EBUSY;
			}
			devpriv->hw_config_bits |= EXT_QUEUE_BIT;
			writew(devpriv->hw_config_bits,
			       devpriv->main_iobase + HW_CONFIG_REG);
			/* clear DAC buffer to prevent weird interactions */
			writew(0,
			       devpriv->main_iobase + DAC_BUFFER_CLEAR_REG);
			/* clear queue pointer */
			writew(0, devpriv->main_iobase + ADC_QUEUE_CLEAR_REG);
			/* load external queue */
			for (i = 0; i < cmd->chanlist_len; i++) {
				unsigned int chanspec = cmd->chanlist[i];
				int use_differential;

				bits = 0;
				/* set channel */
				bits |= adc_chan_bits(CR_CHAN(chanspec));
				/* set gain */
				bits |= ai_range_bits_6xxx(dev,
							   CR_RANGE(chanspec));
				/* set single-ended / differential */
				use_differential = 0;
				if (CR_AREF(chanspec) == AREF_DIFF)
					use_differential = 1;
				bits |= se_diff_bit_6xxx(dev, use_differential);

				if (CR_AREF(cmd->chanlist[i]) == AREF_COMMON)
					bits |= ADC_COMMON_BIT;
				/* mark end of queue */
				if (i == cmd->chanlist_len - 1)
					bits |= QUEUE_EOSCAN_BIT |
						QUEUE_EOSEQ_BIT;
				writew(bits,
				       devpriv->main_iobase +
				       ADC_QUEUE_FIFO_REG);
			}
			/*
			 * doing a queue clear is not specified in board docs,
			 * but required for reliable operation
			 */
			writew(0, devpriv->main_iobase + ADC_QUEUE_CLEAR_REG);
			/* prime queue holding register */
			writew(0, devpriv->main_iobase + ADC_QUEUE_LOAD_REG);
		}
	} else {
		unsigned short old_cal_range_bits = devpriv->i2c_cal_range_bits;

		devpriv->i2c_cal_range_bits &= ~ADC_SRC_4020_MASK;
		/* select BNC inputs */
		devpriv->i2c_cal_range_bits |= adc_src_4020_bits(4);
		/* select ranges */
		for (i = 0; i < cmd->chanlist_len; i++) {
			unsigned int channel = CR_CHAN(cmd->chanlist[i]);
			unsigned int range = CR_RANGE(cmd->chanlist[i]);

			if (range == 0)
				devpriv->i2c_cal_range_bits |=
					attenuate_bit(channel);
			else
				devpriv->i2c_cal_range_bits &=
					~attenuate_bit(channel);
		}
		/*
		 * update calibration/range i2c register only if necessary,
		 * as it is very slow
		 */
		if (old_cal_range_bits != devpriv->i2c_cal_range_bits) {
			u8 i2c_data = devpriv->i2c_cal_range_bits;

			i2c_write(dev, RANGE_CAL_I2C_ADDR, &i2c_data,
				  sizeof(i2c_data));
		}
	}
	return 0;
}

static inline void load_first_dma_descriptor(struct comedi_device *dev,
					     unsigned int dma_channel,
					     unsigned int descriptor_bits)
{
	struct pcidas64_private *devpriv = dev->private;

	/*
	 * The transfer size, pci address, and local address registers
	 * are supposedly unused during chained dma,
	 * but I have found that left over values from last operation
	 * occasionally cause problems with transfer of first dma
	 * block.  Initializing them to zero seems to fix the problem.
	 */
	if (dma_channel) {
		writel(0, devpriv->plx9080_iobase + PLX_REG_DMASIZ1);
		writel(0, devpriv->plx9080_iobase + PLX_REG_DMAPADR1);
		writel(0, devpriv->plx9080_iobase + PLX_REG_DMALADR1);
		writel(descriptor_bits,
		       devpriv->plx9080_iobase + PLX_REG_DMADPR1);
	} else {
		writel(0, devpriv->plx9080_iobase + PLX_REG_DMASIZ0);
		writel(0, devpriv->plx9080_iobase + PLX_REG_DMAPADR0);
		writel(0, devpriv->plx9080_iobase + PLX_REG_DMALADR0);
		writel(descriptor_bits,
		       devpriv->plx9080_iobase + PLX_REG_DMADPR0);
	}
}

static int ai_cmd(struct comedi_device *dev, struct comedi_subdevice *s)
{
	const struct pcidas64_board *board = dev->board_ptr;
	struct pcidas64_private *devpriv = dev->private;
	struct comedi_async *async = s->async;
	struct comedi_cmd *cmd = &async->cmd;
	u32 bits;
	unsigned int i;
	unsigned long flags;
	int retval;

	disable_ai_pacing(dev);
	abort_dma(dev, 1);

	retval = setup_channel_queue(dev, cmd);
	if (retval < 0)
		return retval;

	/* make sure internal calibration source is turned off */
	writew(0, devpriv->main_iobase + CALIBRATION_REG);

	set_ai_pacing(dev, cmd);

	setup_sample_counters(dev, cmd);

	enable_ai_interrupts(dev, cmd);

	spin_lock_irqsave(&dev->spinlock, flags);
	/* set mode, allow conversions through software gate */
	devpriv->adc_control1_bits |= ADC_SW_GATE_BIT;
	devpriv->adc_control1_bits &= ~ADC_DITHER_BIT;
	if (board->layout != LAYOUT_4020) {
		devpriv->adc_control1_bits &= ~ADC_MODE_MASK;
		if (cmd->convert_src == TRIG_EXT)
			/* good old mode 13 */
			devpriv->adc_control1_bits |= adc_mode_bits(13);
		else
			/* mode 8.  What else could you need? */
			devpriv->adc_control1_bits |= adc_mode_bits(8);
	} else {
		devpriv->adc_control1_bits &= ~CHANNEL_MODE_4020_MASK;
		if (cmd->chanlist_len == 4)
			devpriv->adc_control1_bits |= FOUR_CHANNEL_4020_BITS;
		else if (cmd->chanlist_len == 2)
			devpriv->adc_control1_bits |= TWO_CHANNEL_4020_BITS;
		devpriv->adc_control1_bits &= ~ADC_LO_CHANNEL_4020_MASK;
		devpriv->adc_control1_bits |=
			adc_lo_chan_4020_bits(CR_CHAN(cmd->chanlist[0]));
		devpriv->adc_control1_bits &= ~ADC_HI_CHANNEL_4020_MASK;
		devpriv->adc_control1_bits |=
			adc_hi_chan_4020_bits(CR_CHAN(cmd->chanlist
						      [cmd->chanlist_len - 1]));
	}
	writew(devpriv->adc_control1_bits,
	       devpriv->main_iobase + ADC_CONTROL1_REG);
	spin_unlock_irqrestore(&dev->spinlock, flags);

	/* clear adc buffer */
	writew(0, devpriv->main_iobase + ADC_BUFFER_CLEAR_REG);

	if ((cmd->flags & CMDF_WAKE_EOS) == 0 ||
	    board->layout == LAYOUT_4020) {
		devpriv->ai_dma_index = 0;

		/* set dma transfer size */
		for (i = 0; i < ai_dma_ring_count(board); i++)
			devpriv->ai_dma_desc[i].transfer_size =
				cpu_to_le32(dma_transfer_size(dev) *
					    sizeof(u16));

		/* give location of first dma descriptor */
		load_first_dma_descriptor(dev, 1,
					  devpriv->ai_dma_desc_bus_addr |
					  PLX_DMADPR_DESCPCI |
					  PLX_DMADPR_TCINTR |
					  PLX_DMADPR_XFERL2P);

		dma_start_sync(dev, 1);
	}

	if (board->layout == LAYOUT_4020) {
		/* set source for external triggers */
		bits = 0;
		if (cmd->start_src == TRIG_EXT && CR_CHAN(cmd->start_arg))
			bits |= EXT_START_TRIG_BNC_BIT;
		if (cmd->stop_src == TRIG_EXT && CR_CHAN(cmd->stop_arg))
			bits |= EXT_STOP_TRIG_BNC_BIT;
		writew(bits, devpriv->main_iobase + DAQ_ATRIG_LOW_4020_REG);
	}

	spin_lock_irqsave(&dev->spinlock, flags);

	/* enable pacing, triggering, etc */
	bits = ADC_ENABLE_BIT | ADC_SOFT_GATE_BITS | ADC_GATE_LEVEL_BIT;
	if (cmd->flags & CMDF_WAKE_EOS)
		bits |= ADC_DMA_DISABLE_BIT;
	/* set start trigger */
	if (cmd->start_src == TRIG_EXT) {
		bits |= ADC_START_TRIG_EXT_BITS;
		if (cmd->start_arg & CR_INVERT)
			bits |= ADC_START_TRIG_FALLING_BIT;
	} else if (cmd->start_src == TRIG_NOW) {
		bits |= ADC_START_TRIG_SOFT_BITS;
	}
	if (use_hw_sample_counter(cmd))
		bits |= ADC_SAMPLE_COUNTER_EN_BIT;
	writew(bits, devpriv->main_iobase + ADC_CONTROL0_REG);

	devpriv->ai_cmd_running = 1;

	spin_unlock_irqrestore(&dev->spinlock, flags);

	/* start acquisition */
	if (cmd->start_src == TRIG_NOW)
		writew(0, devpriv->main_iobase + ADC_START_REG);

	return 0;
}

/* read num_samples from 16 bit wide ai fifo */
static void pio_drain_ai_fifo_16(struct comedi_device *dev)
{
	struct pcidas64_private *devpriv = dev->private;
	struct comedi_subdevice *s = dev->read_subdev;
	unsigned int i;
	u16 prepost_bits;
	int read_segment, read_index, write_segment, write_index;
	int num_samples;

	do {
		/* get least significant 15 bits */
		read_index = readw(devpriv->main_iobase + ADC_READ_PNTR_REG) &
			     0x7fff;
		write_index = readw(devpriv->main_iobase + ADC_WRITE_PNTR_REG) &
			      0x7fff;
		/*
		 * Get most significant bits (grey code).
		 * Different boards use different code so use a scheme
		 * that doesn't depend on encoding.  This read must
		 * occur after reading least significant 15 bits to avoid race
		 * with fifo switching to next segment.
		 */
		prepost_bits = readw(devpriv->main_iobase + PREPOST_REG);

		/*
		 * if read and write pointers are not on the same fifo segment,
		 * read to the end of the read segment
		 */
		read_segment = adc_upper_read_ptr_code(prepost_bits);
		write_segment = adc_upper_write_ptr_code(prepost_bits);

		if (read_segment != write_segment)
			num_samples =
				devpriv->ai_fifo_segment_length - read_index;
		else
			num_samples = write_index - read_index;
		if (num_samples < 0) {
			dev_err(dev->class_dev,
				"cb_pcidas64: bug! num_samples < 0\n");
			break;
		}

		num_samples = comedi_nsamples_left(s, num_samples);
		if (num_samples == 0)
			break;

		for (i = 0; i < num_samples; i++) {
			unsigned short val;

			val = readw(devpriv->main_iobase + ADC_FIFO_REG);
			comedi_buf_write_samples(s, &val, 1);
		}

	} while (read_segment != write_segment);
}

/*
 * Read from 32 bit wide ai fifo of 4020 - deal with insane grey coding of
 * pointers.  The pci-4020 hardware only supports dma transfers (it only
 * supports the use of pio for draining the last remaining points from the
 * fifo when a data acquisition operation has completed).
 */
static void pio_drain_ai_fifo_32(struct comedi_device *dev)
{
	struct pcidas64_private *devpriv = dev->private;
	struct comedi_subdevice *s = dev->read_subdev;
	unsigned int nsamples;
	unsigned int i;
	u32 fifo_data;
	int write_code =
		readw(devpriv->main_iobase + ADC_WRITE_PNTR_REG) & 0x7fff;
	int read_code =
		readw(devpriv->main_iobase + ADC_READ_PNTR_REG) & 0x7fff;

	nsamples = comedi_nsamples_left(s, 100000);
	for (i = 0; read_code != write_code && i < nsamples;) {
		unsigned short val;

		fifo_data = readl(dev->mmio + ADC_FIFO_REG);
		val = fifo_data & 0xffff;
		comedi_buf_write_samples(s, &val, 1);
		i++;
		if (i < nsamples) {
			val = (fifo_data >> 16) & 0xffff;
			comedi_buf_write_samples(s, &val, 1);
			i++;
		}
		read_code = readw(devpriv->main_iobase + ADC_READ_PNTR_REG) &
			    0x7fff;
	}
}

/* empty fifo */
static void pio_drain_ai_fifo(struct comedi_device *dev)
{
	const struct pcidas64_board *board = dev->board_ptr;

	if (board->layout == LAYOUT_4020)
		pio_drain_ai_fifo_32(dev);
	else
		pio_drain_ai_fifo_16(dev);
}

static void drain_dma_buffers(struct comedi_device *dev, unsigned int channel)
{
	const struct pcidas64_board *board = dev->board_ptr;
	struct pcidas64_private *devpriv = dev->private;
	struct comedi_subdevice *s = dev->read_subdev;
	u32 next_transfer_addr;
	int j;
	int num_samples = 0;
	void __iomem *pci_addr_reg;

	pci_addr_reg = devpriv->plx9080_iobase + PLX_REG_DMAPADR(channel);

	/* loop until we have read all the full buffers */
	for (j = 0, next_transfer_addr = readl(pci_addr_reg);
	     (next_transfer_addr <
	      devpriv->ai_buffer_bus_addr[devpriv->ai_dma_index] ||
	      next_transfer_addr >=
	      devpriv->ai_buffer_bus_addr[devpriv->ai_dma_index] +
	      DMA_BUFFER_SIZE) && j < ai_dma_ring_count(board); j++) {
		/* transfer data from dma buffer to comedi buffer */
		num_samples = comedi_nsamples_left(s, dma_transfer_size(dev));
		comedi_buf_write_samples(s,
				devpriv->ai_buffer[devpriv->ai_dma_index],
				num_samples);
		devpriv->ai_dma_index = (devpriv->ai_dma_index + 1) %
					ai_dma_ring_count(board);
	}
	/*
	 * XXX check for dma ring buffer overrun
	 * (use end-of-chain bit to mark last unused buffer)
	 */
}

static void handle_ai_interrupt(struct comedi_device *dev,
				unsigned short status,
				unsigned int plx_status)
{
	const struct pcidas64_board *board = dev->board_ptr;
	struct pcidas64_private *devpriv = dev->private;
	struct comedi_subdevice *s = dev->read_subdev;
	struct comedi_async *async = s->async;
	struct comedi_cmd *cmd = &async->cmd;
	u8 dma1_status;
	unsigned long flags;

	/* check for fifo overrun */
	if (status & ADC_OVERRUN_BIT) {
		dev_err(dev->class_dev, "fifo overrun\n");
		async->events |= COMEDI_CB_ERROR;
	}
	/* spin lock makes sure no one else changes plx dma control reg */
	spin_lock_irqsave(&dev->spinlock, flags);
	dma1_status = readb(devpriv->plx9080_iobase + PLX_REG_DMACSR1);
	if (plx_status & PLX_INTCSR_DMA1IA) {	/* dma chan 1 interrupt */
		writeb((dma1_status & PLX_DMACSR_ENABLE) | PLX_DMACSR_CLEARINTR,
		       devpriv->plx9080_iobase + PLX_REG_DMACSR1);

		if (dma1_status & PLX_DMACSR_ENABLE)
			drain_dma_buffers(dev, 1);
	}
	spin_unlock_irqrestore(&dev->spinlock, flags);

	/* drain fifo with pio */
	if ((status & ADC_DONE_BIT) ||
	    ((cmd->flags & CMDF_WAKE_EOS) &&
	     (status & ADC_INTR_PENDING_BIT) &&
	     (board->layout != LAYOUT_4020))) {
		spin_lock_irqsave(&dev->spinlock, flags);
		if (devpriv->ai_cmd_running) {
			spin_unlock_irqrestore(&dev->spinlock, flags);
			pio_drain_ai_fifo(dev);
		} else {
			spin_unlock_irqrestore(&dev->spinlock, flags);
		}
	}
	/* if we are have all the data, then quit */
	if ((cmd->stop_src == TRIG_COUNT &&
	     async->scans_done >= cmd->stop_arg) ||
	    (cmd->stop_src == TRIG_EXT && (status & ADC_STOP_BIT)))
		async->events |= COMEDI_CB_EOA;

	comedi_handle_events(dev, s);
}

static inline unsigned int prev_ao_dma_index(struct comedi_device *dev)
{
	struct pcidas64_private *devpriv = dev->private;
	unsigned int buffer_index;

	if (devpriv->ao_dma_index == 0)
		buffer_index = AO_DMA_RING_COUNT - 1;
	else
		buffer_index = devpriv->ao_dma_index - 1;
	return buffer_index;
}

static int last_ao_dma_load_completed(struct comedi_device *dev)
{
	struct pcidas64_private *devpriv = dev->private;
	unsigned int buffer_index;
	unsigned int transfer_address;
	unsigned short dma_status;

	buffer_index = prev_ao_dma_index(dev);
	dma_status = readb(devpriv->plx9080_iobase + PLX_REG_DMACSR0);
	if ((dma_status & PLX_DMACSR_DONE) == 0)
		return 0;

	transfer_address =
		readl(devpriv->plx9080_iobase + PLX_REG_DMAPADR0);
	if (transfer_address != devpriv->ao_buffer_bus_addr[buffer_index])
		return 0;

	return 1;
}

static inline int ao_dma_needs_restart(struct comedi_device *dev,
				       unsigned short dma_status)
{
	if ((dma_status & PLX_DMACSR_DONE) == 0 ||
	    (dma_status & PLX_DMACSR_ENABLE) == 0)
		return 0;
	if (last_ao_dma_load_completed(dev))
		return 0;

	return 1;
}

static void restart_ao_dma(struct comedi_device *dev)
{
	struct pcidas64_private *devpriv = dev->private;
	unsigned int dma_desc_bits;

	dma_desc_bits = readl(devpriv->plx9080_iobase + PLX_REG_DMADPR0);
	dma_desc_bits &= ~PLX_DMADPR_CHAINEND;
	load_first_dma_descriptor(dev, 0, dma_desc_bits);

	dma_start_sync(dev, 0);
}

static unsigned int cb_pcidas64_ao_fill_buffer(struct comedi_device *dev,
					       struct comedi_subdevice *s,
					       unsigned short *dest,
					       unsigned int max_bytes)
{
	unsigned int nsamples = comedi_bytes_to_samples(s, max_bytes);
	unsigned int actual_bytes;

	nsamples = comedi_nsamples_left(s, nsamples);
	actual_bytes = comedi_buf_read_samples(s, dest, nsamples);

	return comedi_bytes_to_samples(s, actual_bytes);
}

static unsigned int load_ao_dma_buffer(struct comedi_device *dev,
				       const struct comedi_cmd *cmd)
{
	struct pcidas64_private *devpriv = dev->private;
	struct comedi_subdevice *s = dev->write_subdev;
	unsigned int buffer_index = devpriv->ao_dma_index;
	unsigned int prev_buffer_index = prev_ao_dma_index(dev);
	unsigned int nsamples;
	unsigned int nbytes;
	unsigned int next_bits;

	nsamples = cb_pcidas64_ao_fill_buffer(dev, s,
					      devpriv->ao_buffer[buffer_index],
					      DMA_BUFFER_SIZE);
	if (nsamples == 0)
		return 0;

	nbytes = comedi_samples_to_bytes(s, nsamples);
	devpriv->ao_dma_desc[buffer_index].transfer_size = cpu_to_le32(nbytes);
	/* set end of chain bit so we catch underruns */
	next_bits = le32_to_cpu(devpriv->ao_dma_desc[buffer_index].next);
	next_bits |= PLX_DMADPR_CHAINEND;
	devpriv->ao_dma_desc[buffer_index].next = cpu_to_le32(next_bits);
	/*
	 * clear end of chain bit on previous buffer now that we have set it
	 * for the last buffer
	 */
	next_bits = le32_to_cpu(devpriv->ao_dma_desc[prev_buffer_index].next);
	next_bits &= ~PLX_DMADPR_CHAINEND;
	devpriv->ao_dma_desc[prev_buffer_index].next = cpu_to_le32(next_bits);

	devpriv->ao_dma_index = (buffer_index + 1) % AO_DMA_RING_COUNT;

	return nbytes;
}

static void load_ao_dma(struct comedi_device *dev, const struct comedi_cmd *cmd)
{
	struct pcidas64_private *devpriv = dev->private;
	unsigned int num_bytes;
	unsigned int next_transfer_addr;
	void __iomem *pci_addr_reg = devpriv->plx9080_iobase + PLX_REG_DMAPADR0;
	unsigned int buffer_index;

	do {
		buffer_index = devpriv->ao_dma_index;
		/* don't overwrite data that hasn't been transferred yet */
		next_transfer_addr = readl(pci_addr_reg);
		if (next_transfer_addr >=
		    devpriv->ao_buffer_bus_addr[buffer_index] &&
		    next_transfer_addr <
		    devpriv->ao_buffer_bus_addr[buffer_index] +
		    DMA_BUFFER_SIZE)
			return;
		num_bytes = load_ao_dma_buffer(dev, cmd);
	} while (num_bytes >= DMA_BUFFER_SIZE);
}

static void handle_ao_interrupt(struct comedi_device *dev,
				unsigned short status, unsigned int plx_status)
{
	struct pcidas64_private *devpriv = dev->private;
	struct comedi_subdevice *s = dev->write_subdev;
	struct comedi_async *async;
	struct comedi_cmd *cmd;
	u8 dma0_status;
	unsigned long flags;

	/* board might not support ao, in which case write_subdev is NULL */
	if (!s)
		return;
	async = s->async;
	cmd = &async->cmd;

	/* spin lock makes sure no one else changes plx dma control reg */
	spin_lock_irqsave(&dev->spinlock, flags);
	dma0_status = readb(devpriv->plx9080_iobase + PLX_REG_DMACSR0);
	if (plx_status & PLX_INTCSR_DMA0IA) {	/*  dma chan 0 interrupt */
		if ((dma0_status & PLX_DMACSR_ENABLE) &&
		    !(dma0_status & PLX_DMACSR_DONE)) {
			writeb(PLX_DMACSR_ENABLE | PLX_DMACSR_CLEARINTR,
			       devpriv->plx9080_iobase + PLX_REG_DMACSR0);
		} else {
			writeb(PLX_DMACSR_CLEARINTR,
			       devpriv->plx9080_iobase + PLX_REG_DMACSR0);
		}
		spin_unlock_irqrestore(&dev->spinlock, flags);
		if (dma0_status & PLX_DMACSR_ENABLE) {
			load_ao_dma(dev, cmd);
			/* try to recover from dma end-of-chain event */
			if (ao_dma_needs_restart(dev, dma0_status))
				restart_ao_dma(dev);
		}
	} else {
		spin_unlock_irqrestore(&dev->spinlock, flags);
	}

	if ((status & DAC_DONE_BIT)) {
		if ((cmd->stop_src == TRIG_COUNT &&
		     async->scans_done >= cmd->stop_arg) ||
		    last_ao_dma_load_completed(dev))
			async->events |= COMEDI_CB_EOA;
		else
			async->events |= COMEDI_CB_ERROR;
	}
	comedi_handle_events(dev, s);
}

static irqreturn_t handle_interrupt(int irq, void *d)
{
	struct comedi_device *dev = d;
	struct pcidas64_private *devpriv = dev->private;
	unsigned short status;
	u32 plx_status;
	u32 plx_bits;

	plx_status = readl(devpriv->plx9080_iobase + PLX_REG_INTCSR);
	status = readw(devpriv->main_iobase + HW_STATUS_REG);

	/*
	 * an interrupt before all the postconfig stuff gets done could
	 * cause a NULL dereference if we continue through the
	 * interrupt handler
	 */
	if (!dev->attached)
		return IRQ_HANDLED;

	handle_ai_interrupt(dev, status, plx_status);
	handle_ao_interrupt(dev, status, plx_status);

	/* clear possible plx9080 interrupt sources */
	if (plx_status & PLX_INTCSR_LDBIA) {
		/* clear local doorbell interrupt */
		plx_bits = readl(devpriv->plx9080_iobase + PLX_REG_L2PDBELL);
		writel(plx_bits, devpriv->plx9080_iobase + PLX_REG_L2PDBELL);
	}

	return IRQ_HANDLED;
}

static int ai_cancel(struct comedi_device *dev, struct comedi_subdevice *s)
{
	struct pcidas64_private *devpriv = dev->private;
	unsigned long flags;

	spin_lock_irqsave(&dev->spinlock, flags);
	if (devpriv->ai_cmd_running == 0) {
		spin_unlock_irqrestore(&dev->spinlock, flags);
		return 0;
	}
	devpriv->ai_cmd_running = 0;
	spin_unlock_irqrestore(&dev->spinlock, flags);

	disable_ai_pacing(dev);

	abort_dma(dev, 1);

	return 0;
}

static int ao_winsn(struct comedi_device *dev, struct comedi_subdevice *s,
		    struct comedi_insn *insn, unsigned int *data)
{
	const struct pcidas64_board *board = dev->board_ptr;
	struct pcidas64_private *devpriv = dev->private;
	unsigned int chan = CR_CHAN(insn->chanspec);
	unsigned int range = CR_RANGE(insn->chanspec);
	unsigned int val = s->readback[chan];
	unsigned int i;

	/* do some initializing */
	writew(0, devpriv->main_iobase + DAC_CONTROL0_REG);

	/* set range */
	set_dac_range_bits(dev, &devpriv->dac_control1_bits, chan, range);
	writew(devpriv->dac_control1_bits,
	       devpriv->main_iobase + DAC_CONTROL1_REG);

	for (i = 0; i < insn->n; i++) {
		/* write to channel */
		val = data[i];
		if (board->layout == LAYOUT_4020) {
			writew(val & 0xff,
			       devpriv->main_iobase + dac_lsb_4020_reg(chan));
			writew((val >> 8) & 0xf,
			       devpriv->main_iobase + dac_msb_4020_reg(chan));
		} else {
			writew(val,
			       devpriv->main_iobase + dac_convert_reg(chan));
		}
	}

	/* remember last output value */
	s->readback[chan] = val;

	return insn->n;
}

static void set_dac_control0_reg(struct comedi_device *dev,
				 const struct comedi_cmd *cmd)
{
	struct pcidas64_private *devpriv = dev->private;
	unsigned int bits = DAC_ENABLE_BIT | WAVEFORM_GATE_LEVEL_BIT |
			    WAVEFORM_GATE_ENABLE_BIT | WAVEFORM_GATE_SELECT_BIT;

	if (cmd->start_src == TRIG_EXT) {
		bits |= WAVEFORM_TRIG_EXT_BITS;
		if (cmd->start_arg & CR_INVERT)
			bits |= WAVEFORM_TRIG_FALLING_BIT;
	} else {
		bits |= WAVEFORM_TRIG_SOFT_BITS;
	}
	if (cmd->scan_begin_src == TRIG_EXT) {
		bits |= DAC_EXT_UPDATE_ENABLE_BIT;
		if (cmd->scan_begin_arg & CR_INVERT)
			bits |= DAC_EXT_UPDATE_FALLING_BIT;
	}
	writew(bits, devpriv->main_iobase + DAC_CONTROL0_REG);
}

static void set_dac_control1_reg(struct comedi_device *dev,
				 const struct comedi_cmd *cmd)
{
	struct pcidas64_private *devpriv = dev->private;
	int i;

	for (i = 0; i < cmd->chanlist_len; i++) {
		int channel, range;

		channel = CR_CHAN(cmd->chanlist[i]);
		range = CR_RANGE(cmd->chanlist[i]);
		set_dac_range_bits(dev, &devpriv->dac_control1_bits, channel,
				   range);
	}
	devpriv->dac_control1_bits |= DAC_SW_GATE_BIT;
	writew(devpriv->dac_control1_bits,
	       devpriv->main_iobase + DAC_CONTROL1_REG);
}

static void set_dac_select_reg(struct comedi_device *dev,
			       const struct comedi_cmd *cmd)
{
	struct pcidas64_private *devpriv = dev->private;
	u16 bits;
	unsigned int first_channel, last_channel;

	first_channel = CR_CHAN(cmd->chanlist[0]);
	last_channel = CR_CHAN(cmd->chanlist[cmd->chanlist_len - 1]);
	if (last_channel < first_channel)
		dev_err(dev->class_dev,
			"bug! last ao channel < first ao channel\n");

	bits = (first_channel & 0x7) | (last_channel & 0x7) << 3;

	writew(bits, devpriv->main_iobase + DAC_SELECT_REG);
}

static unsigned int get_ao_divisor(unsigned int ns, unsigned int flags)
{
	return get_divisor(ns, flags) - 2;
}

static void set_dac_interval_regs(struct comedi_device *dev,
				  const struct comedi_cmd *cmd)
{
	struct pcidas64_private *devpriv = dev->private;
	unsigned int divisor;

	if (cmd->scan_begin_src != TRIG_TIMER)
		return;

	divisor = get_ao_divisor(cmd->scan_begin_arg, cmd->flags);
	if (divisor > max_counter_value) {
		dev_err(dev->class_dev, "bug! ao divisor too big\n");
		divisor = max_counter_value;
	}
	writew(divisor & 0xffff,
	       devpriv->main_iobase + DAC_SAMPLE_INTERVAL_LOWER_REG);
	writew((divisor >> 16) & 0xff,
	       devpriv->main_iobase + DAC_SAMPLE_INTERVAL_UPPER_REG);
}

static int prep_ao_dma(struct comedi_device *dev, const struct comedi_cmd *cmd)
{
	struct pcidas64_private *devpriv = dev->private;
	struct comedi_subdevice *s = dev->write_subdev;
	unsigned int nsamples;
	unsigned int nbytes;
	int i;

	/*
	 * clear queue pointer too, since external queue has
	 * weird interactions with ao fifo
	 */
	writew(0, devpriv->main_iobase + ADC_QUEUE_CLEAR_REG);
	writew(0, devpriv->main_iobase + DAC_BUFFER_CLEAR_REG);

	nsamples = cb_pcidas64_ao_fill_buffer(dev, s,
					      devpriv->ao_bounce_buffer,
					      DAC_FIFO_SIZE);
	if (nsamples == 0)
		return -1;

	for (i = 0; i < nsamples; i++) {
		writew(devpriv->ao_bounce_buffer[i],
		       devpriv->main_iobase + DAC_FIFO_REG);
	}

	if (cmd->stop_src == TRIG_COUNT &&
	    s->async->scans_done >= cmd->stop_arg)
		return 0;

	nbytes = load_ao_dma_buffer(dev, cmd);
	if (nbytes == 0)
		return -1;
	load_ao_dma(dev, cmd);

	dma_start_sync(dev, 0);

	return 0;
}

static inline int external_ai_queue_in_use(struct comedi_device *dev)
{
	const struct pcidas64_board *board = dev->board_ptr;

	if (!dev->read_subdev->busy)
		return 0;
	if (board->layout == LAYOUT_4020)
		return 0;
	else if (use_internal_queue_6xxx(&dev->read_subdev->async->cmd))
		return 0;
	return 1;
}

static int ao_inttrig(struct comedi_device *dev, struct comedi_subdevice *s,
		      unsigned int trig_num)
{
	struct pcidas64_private *devpriv = dev->private;
	struct comedi_cmd *cmd = &s->async->cmd;
	int retval;

	if (trig_num != cmd->start_arg)
		return -EINVAL;

	retval = prep_ao_dma(dev, cmd);
	if (retval < 0)
		return -EPIPE;

	set_dac_control0_reg(dev, cmd);

	if (cmd->start_src == TRIG_INT)
		writew(0, devpriv->main_iobase + DAC_START_REG);

	s->async->inttrig = NULL;

	return 0;
}

static int ao_cmd(struct comedi_device *dev, struct comedi_subdevice *s)
{
	struct pcidas64_private *devpriv = dev->private;
	struct comedi_cmd *cmd = &s->async->cmd;

	if (external_ai_queue_in_use(dev)) {
		warn_external_queue(dev);
		return -EBUSY;
	}
	/* disable analog output system during setup */
	writew(0x0, devpriv->main_iobase + DAC_CONTROL0_REG);

	devpriv->ao_dma_index = 0;

	set_dac_select_reg(dev, cmd);
	set_dac_interval_regs(dev, cmd);
	load_first_dma_descriptor(dev, 0, devpriv->ao_dma_desc_bus_addr |
				  PLX_DMADPR_DESCPCI | PLX_DMADPR_TCINTR);

	set_dac_control1_reg(dev, cmd);
	s->async->inttrig = ao_inttrig;

	return 0;
}

static int cb_pcidas64_ao_check_chanlist(struct comedi_device *dev,
					 struct comedi_subdevice *s,
					 struct comedi_cmd *cmd)
{
	unsigned int chan0 = CR_CHAN(cmd->chanlist[0]);
	int i;

	for (i = 1; i < cmd->chanlist_len; i++) {
		unsigned int chan = CR_CHAN(cmd->chanlist[i]);

		if (chan != (chan0 + i)) {
			dev_dbg(dev->class_dev,
				"chanlist must use consecutive channels\n");
			return -EINVAL;
		}
	}

	return 0;
}

static int ao_cmdtest(struct comedi_device *dev, struct comedi_subdevice *s,
		      struct comedi_cmd *cmd)
{
	const struct pcidas64_board *board = dev->board_ptr;
	int err = 0;
	unsigned int tmp_arg;

	/* Step 1 : check if triggers are trivially valid */

	err |= comedi_check_trigger_src(&cmd->start_src, TRIG_INT | TRIG_EXT);
	err |= comedi_check_trigger_src(&cmd->scan_begin_src,
					TRIG_TIMER | TRIG_EXT);
	err |= comedi_check_trigger_src(&cmd->convert_src, TRIG_NOW);
	err |= comedi_check_trigger_src(&cmd->scan_end_src, TRIG_COUNT);
	err |= comedi_check_trigger_src(&cmd->stop_src, TRIG_NONE);

	if (err)
		return 1;

	/* Step 2a : make sure trigger sources are unique */

	err |= comedi_check_trigger_is_unique(cmd->start_src);
	err |= comedi_check_trigger_is_unique(cmd->scan_begin_src);

	/* Step 2b : and mutually compatible */

	if (cmd->convert_src == TRIG_EXT && cmd->scan_begin_src == TRIG_TIMER)
		err |= -EINVAL;
	if (cmd->stop_src != TRIG_COUNT &&
	    cmd->stop_src != TRIG_NONE && cmd->stop_src != TRIG_EXT)
		err |= -EINVAL;

	if (err)
		return 2;

	/* Step 3: check if arguments are trivially valid */

	err |= comedi_check_trigger_arg_is(&cmd->start_arg, 0);

	if (cmd->scan_begin_src == TRIG_TIMER) {
		err |= comedi_check_trigger_arg_min(&cmd->scan_begin_arg,
						    board->ao_scan_speed);
		if (get_ao_divisor(cmd->scan_begin_arg, cmd->flags) >
		    max_counter_value) {
			cmd->scan_begin_arg = (max_counter_value + 2) *
					      TIMER_BASE;
			err |= -EINVAL;
		}
	}

	err |= comedi_check_trigger_arg_min(&cmd->chanlist_len, 1);
	err |= comedi_check_trigger_arg_is(&cmd->scan_end_arg,
					   cmd->chanlist_len);

	if (err)
		return 3;

	/* step 4: fix up any arguments */

	if (cmd->scan_begin_src == TRIG_TIMER) {
		tmp_arg = cmd->scan_begin_arg;
		cmd->scan_begin_arg = get_divisor(cmd->scan_begin_arg,
						  cmd->flags) * TIMER_BASE;
		if (tmp_arg != cmd->scan_begin_arg)
			err++;
	}

	if (err)
		return 4;

	/* Step 5: check channel list if it exists */
	if (cmd->chanlist && cmd->chanlist_len > 0)
		err |= cb_pcidas64_ao_check_chanlist(dev, s, cmd);

	if (err)
		return 5;

	return 0;
}

static int ao_cancel(struct comedi_device *dev, struct comedi_subdevice *s)
{
	struct pcidas64_private *devpriv = dev->private;

	writew(0x0, devpriv->main_iobase + DAC_CONTROL0_REG);
	abort_dma(dev, 0);
	return 0;
}

static int dio_callback_4020(struct comedi_device *dev,
			     int dir, int port, int data, unsigned long iobase)
{
	struct pcidas64_private *devpriv = dev->private;

	if (dir) {
		writew(data, devpriv->main_iobase + iobase + 2 * port);
		return 0;
	}
	return readw(devpriv->main_iobase + iobase + 2 * port);
}

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

	bits = readb(dev->mmio + DI_REG);
	bits &= 0xf;
	data[1] = bits;
	data[0] = 0;

	return insn->n;
}

static int do_wbits(struct comedi_device *dev,
		    struct comedi_subdevice *s,
		    struct comedi_insn *insn,
		    unsigned int *data)
{
	if (comedi_dio_update_state(s, data))
		writeb(s->state, dev->mmio + DO_REG);

	data[1] = s->state;

	return insn->n;
}

static int dio_60xx_config_insn(struct comedi_device *dev,
				struct comedi_subdevice *s,
				struct comedi_insn *insn,
				unsigned int *data)
{
	int ret;

	ret = comedi_dio_insn_config(dev, s, insn, data, 0);
	if (ret)
		return ret;

	writeb(s->io_bits, dev->mmio + DIO_DIRECTION_60XX_REG);

	return insn->n;
}

static int dio_60xx_wbits(struct comedi_device *dev,
			  struct comedi_subdevice *s,
			  struct comedi_insn *insn,
			  unsigned int *data)
{
	if (comedi_dio_update_state(s, data))
		writeb(s->state, dev->mmio + DIO_DATA_60XX_REG);

	data[1] = readb(dev->mmio + DIO_DATA_60XX_REG);

	return insn->n;
}

/*
 * pci-6025 8800 caldac:
 * address 0 == dac channel 0 offset
 * address 1 == dac channel 0 gain
 * address 2 == dac channel 1 offset
 * address 3 == dac channel 1 gain
 * address 4 == fine adc offset
 * address 5 == coarse adc offset
 * address 6 == coarse adc gain
 * address 7 == fine adc gain
 */
/*
 * pci-6402/16 uses all 8 channels for dac:
 * address 0 == dac channel 0 fine gain
 * address 1 == dac channel 0 coarse gain
 * address 2 == dac channel 0 coarse offset
 * address 3 == dac channel 1 coarse offset
 * address 4 == dac channel 1 fine gain
 * address 5 == dac channel 1 coarse gain
 * address 6 == dac channel 0 fine offset
 * address 7 == dac channel 1 fine offset
 */

static int caldac_8800_write(struct comedi_device *dev, unsigned int address,
			     u8 value)
{
	struct pcidas64_private *devpriv = dev->private;
	static const int num_caldac_channels = 8;
	static const int bitstream_length = 11;
	unsigned int bitstream = ((address & 0x7) << 8) | value;
	unsigned int bit, register_bits;
	static const int caldac_8800_udelay = 1;

	if (address >= num_caldac_channels) {
		dev_err(dev->class_dev, "illegal caldac channel\n");
		return -1;
	}
	for (bit = 1 << (bitstream_length - 1); bit; bit >>= 1) {
		register_bits = 0;
		if (bitstream & bit)
			register_bits |= SERIAL_DATA_IN_BIT;
		udelay(caldac_8800_udelay);
		writew(register_bits, devpriv->main_iobase + CALIBRATION_REG);
		register_bits |= SERIAL_CLOCK_BIT;
		udelay(caldac_8800_udelay);
		writew(register_bits, devpriv->main_iobase + CALIBRATION_REG);
	}
	udelay(caldac_8800_udelay);
	writew(SELECT_8800_BIT, devpriv->main_iobase + CALIBRATION_REG);
	udelay(caldac_8800_udelay);
	writew(0, devpriv->main_iobase + CALIBRATION_REG);
	udelay(caldac_8800_udelay);
	return 0;
}

/* 4020 caldacs */
static int caldac_i2c_write(struct comedi_device *dev,
			    unsigned int caldac_channel, unsigned int value)
{
	u8 serial_bytes[3];
	u8 i2c_addr;
	enum pointer_bits {
		/* manual has gain and offset bits switched */
		OFFSET_0_2 = 0x1,
		GAIN_0_2 = 0x2,
		OFFSET_1_3 = 0x4,
		GAIN_1_3 = 0x8,
	};
	enum data_bits {
		NOT_CLEAR_REGISTERS = 0x20,
	};

	switch (caldac_channel) {
	case 0:					/* chan 0 offset */
		i2c_addr = CALDAC0_I2C_ADDR;
		serial_bytes[0] = OFFSET_0_2;
		break;
	case 1:					/* chan 1 offset */
		i2c_addr = CALDAC0_I2C_ADDR;
		serial_bytes[0] = OFFSET_1_3;
		break;
	case 2:					/* chan 2 offset */
		i2c_addr = CALDAC1_I2C_ADDR;
		serial_bytes[0] = OFFSET_0_2;
		break;
	case 3:					/* chan 3 offset */
		i2c_addr = CALDAC1_I2C_ADDR;
		serial_bytes[0] = OFFSET_1_3;
		break;
	case 4:					/* chan 0 gain */
		i2c_addr = CALDAC0_I2C_ADDR;
		serial_bytes[0] = GAIN_0_2;
		break;
	case 5:					/* chan 1 gain */
		i2c_addr = CALDAC0_I2C_ADDR;
		serial_bytes[0] = GAIN_1_3;
		break;
	case 6:					/* chan 2 gain */
		i2c_addr = CALDAC1_I2C_ADDR;
		serial_bytes[0] = GAIN_0_2;
		break;
	case 7:					/* chan 3 gain */
		i2c_addr = CALDAC1_I2C_ADDR;
		serial_bytes[0] = GAIN_1_3;
		break;
	default:
		dev_err(dev->class_dev, "invalid caldac channel\n");
		return -1;
	}
	serial_bytes[1] = NOT_CLEAR_REGISTERS | ((value >> 8) & 0xf);
	serial_bytes[2] = value & 0xff;
	i2c_write(dev, i2c_addr, serial_bytes, 3);
	return 0;
}

static void caldac_write(struct comedi_device *dev, unsigned int channel,
			 unsigned int value)
{
	const struct pcidas64_board *board = dev->board_ptr;

	switch (board->layout) {
	case LAYOUT_60XX:
	case LAYOUT_64XX:
		caldac_8800_write(dev, channel, value);
		break;
	case LAYOUT_4020:
		caldac_i2c_write(dev, channel, value);
		break;
	default:
		break;
	}
}

static int cb_pcidas64_calib_insn_write(struct comedi_device *dev,
					struct comedi_subdevice *s,
					struct comedi_insn *insn,
					unsigned int *data)
{
	unsigned int chan = CR_CHAN(insn->chanspec);

	/*
	 * Programming the calib device is slow. Only write the
	 * last data value if the value has changed.
	 */
	if (insn->n) {
		unsigned int val = data[insn->n - 1];

		if (s->readback[chan] != val) {
			caldac_write(dev, chan, val);
			s->readback[chan] = val;
		}
	}

	return insn->n;
}

static void ad8402_write(struct comedi_device *dev, unsigned int channel,
			 unsigned int value)
{
	struct pcidas64_private *devpriv = dev->private;
	static const int bitstream_length = 10;
	unsigned int bit, register_bits;
	unsigned int bitstream = ((channel & 0x3) << 8) | (value & 0xff);
	static const int ad8402_udelay = 1;

	register_bits = SELECT_8402_64XX_BIT;
	udelay(ad8402_udelay);
	writew(register_bits, devpriv->main_iobase + CALIBRATION_REG);

	for (bit = 1 << (bitstream_length - 1); bit; bit >>= 1) {
		if (bitstream & bit)
			register_bits |= SERIAL_DATA_IN_BIT;
		else
			register_bits &= ~SERIAL_DATA_IN_BIT;
		udelay(ad8402_udelay);
		writew(register_bits, devpriv->main_iobase + CALIBRATION_REG);
		udelay(ad8402_udelay);
		writew(register_bits | SERIAL_CLOCK_BIT,
		       devpriv->main_iobase + CALIBRATION_REG);
	}

	udelay(ad8402_udelay);
	writew(0, devpriv->main_iobase + CALIBRATION_REG);
}

/* for pci-das6402/16, channel 0 is analog input gain and channel 1 is offset */
static int cb_pcidas64_ad8402_insn_write(struct comedi_device *dev,
					 struct comedi_subdevice *s,
					 struct comedi_insn *insn,
					 unsigned int *data)
{
	unsigned int chan = CR_CHAN(insn->chanspec);

	/*
	 * Programming the calib device is slow. Only write the
	 * last data value if the value has changed.
	 */
	if (insn->n) {
		unsigned int val = data[insn->n - 1];

		if (s->readback[chan] != val) {
			ad8402_write(dev, chan, val);
			s->readback[chan] = val;
		}
	}

	return insn->n;
}

static u16 read_eeprom(struct comedi_device *dev, u8 address)
{
	struct pcidas64_private *devpriv = dev->private;
	static const int bitstream_length = 11;
	static const int read_command = 0x6;
	unsigned int bitstream = (read_command << 8) | address;
	unsigned int bit;
	void __iomem * const plx_control_addr =
		devpriv->plx9080_iobase + PLX_REG_CNTRL;
	u16 value;
	static const int value_length = 16;
	static const int eeprom_udelay = 1;

	udelay(eeprom_udelay);
	devpriv->plx_control_bits &= ~PLX_CNTRL_EESK & ~PLX_CNTRL_EECS;
	/* make sure we don't send anything to the i2c bus on 4020 */
	devpriv->plx_control_bits |= PLX_CNTRL_USERO;
	writel(devpriv->plx_control_bits, plx_control_addr);
	/* activate serial eeprom */
	udelay(eeprom_udelay);
	devpriv->plx_control_bits |= PLX_CNTRL_EECS;
	writel(devpriv->plx_control_bits, plx_control_addr);

	/* write read command and desired memory address */
	for (bit = 1 << (bitstream_length - 1); bit; bit >>= 1) {
		/* set bit to be written */
		udelay(eeprom_udelay);
		if (bitstream & bit)
			devpriv->plx_control_bits |= PLX_CNTRL_EEWB;
		else
			devpriv->plx_control_bits &= ~PLX_CNTRL_EEWB;
		writel(devpriv->plx_control_bits, plx_control_addr);
		/* clock in bit */
		udelay(eeprom_udelay);
		devpriv->plx_control_bits |= PLX_CNTRL_EESK;
		writel(devpriv->plx_control_bits, plx_control_addr);
		udelay(eeprom_udelay);
		devpriv->plx_control_bits &= ~PLX_CNTRL_EESK;
		writel(devpriv->plx_control_bits, plx_control_addr);
	}
	/* read back value from eeprom memory location */
	value = 0;
	for (bit = 1 << (value_length - 1); bit; bit >>= 1) {
		/* clock out bit */
		udelay(eeprom_udelay);
		devpriv->plx_control_bits |= PLX_CNTRL_EESK;
		writel(devpriv->plx_control_bits, plx_control_addr);
		udelay(eeprom_udelay);
		devpriv->plx_control_bits &= ~PLX_CNTRL_EESK;
		writel(devpriv->plx_control_bits, plx_control_addr);
		udelay(eeprom_udelay);
		if (readl(plx_control_addr) & PLX_CNTRL_EERB)
			value |= bit;
	}

	/* deactivate eeprom serial input */
	udelay(eeprom_udelay);
	devpriv->plx_control_bits &= ~PLX_CNTRL_EECS;
	writel(devpriv->plx_control_bits, plx_control_addr);

	return value;
}

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

	if (insn->n) {
		/* No point reading the same EEPROM location more than once. */
		val = read_eeprom(dev, CR_CHAN(insn->chanspec));
		for (i = 0; i < insn->n; i++)
			data[i] = val;
	}

	return insn->n;
}

/* Allocate and initialize the subdevice structures. */
static int setup_subdevices(struct comedi_device *dev)
{
	const struct pcidas64_board *board = dev->board_ptr;
	struct pcidas64_private *devpriv = dev->private;
	struct comedi_subdevice *s;
	int i;
	int ret;

	ret = comedi_alloc_subdevices(dev, 10);
	if (ret)
		return ret;

	s = &dev->subdevices[0];
	/* analog input subdevice */
	dev->read_subdev = s;
	s->type = COMEDI_SUBD_AI;
	s->subdev_flags = SDF_READABLE | SDF_GROUND | SDF_DITHER | SDF_CMD_READ;
	if (board->layout == LAYOUT_60XX)
		s->subdev_flags |= SDF_COMMON | SDF_DIFF;
	else if (board->layout == LAYOUT_64XX)
		s->subdev_flags |= SDF_DIFF;
	/* XXX Number of inputs in differential mode is ignored */
	s->n_chan = board->ai_se_chans;
	s->len_chanlist = 0x2000;
	s->maxdata = (1 << board->ai_bits) - 1;
	s->range_table = board->ai_range_table;
	s->insn_read = ai_rinsn;
	s->insn_config = ai_config_insn;
	s->do_cmd = ai_cmd;
	s->do_cmdtest = ai_cmdtest;
	s->cancel = ai_cancel;
	if (board->layout == LAYOUT_4020) {
		u8 data;
		/*
		 * set adc to read from inputs
		 * (not internal calibration sources)
		 */
		devpriv->i2c_cal_range_bits = adc_src_4020_bits(4);
		/* set channels to +-5 volt input ranges */
		for (i = 0; i < s->n_chan; i++)
			devpriv->i2c_cal_range_bits |= attenuate_bit(i);
		data = devpriv->i2c_cal_range_bits;
		i2c_write(dev, RANGE_CAL_I2C_ADDR, &data, sizeof(data));
	}

	/* analog output subdevice */
	s = &dev->subdevices[1];
	if (board->ao_nchan) {
		s->type = COMEDI_SUBD_AO;
		s->subdev_flags = SDF_READABLE | SDF_WRITABLE |
				  SDF_GROUND | SDF_CMD_WRITE;
		s->n_chan = board->ao_nchan;
		s->maxdata = (1 << board->ao_bits) - 1;
		s->range_table = board->ao_range_table;
		s->insn_write = ao_winsn;

		ret = comedi_alloc_subdev_readback(s);
		if (ret)
			return ret;

		if (ao_cmd_is_supported(board)) {
			dev->write_subdev = s;
			s->do_cmdtest = ao_cmdtest;
			s->do_cmd = ao_cmd;
			s->len_chanlist = board->ao_nchan;
			s->cancel = ao_cancel;
		}
	} else {
		s->type = COMEDI_SUBD_UNUSED;
	}

	/* digital input */
	s = &dev->subdevices[2];
	if (board->layout == LAYOUT_64XX) {
		s->type = COMEDI_SUBD_DI;
		s->subdev_flags = SDF_READABLE;
		s->n_chan = 4;
		s->maxdata = 1;
		s->range_table = &range_digital;
		s->insn_bits = di_rbits;
	} else {
		s->type = COMEDI_SUBD_UNUSED;
	}

	/* digital output */
	if (board->layout == LAYOUT_64XX) {
		s = &dev->subdevices[3];
		s->type = COMEDI_SUBD_DO;
		s->subdev_flags = SDF_WRITABLE;
		s->n_chan = 4;
		s->maxdata = 1;
		s->range_table = &range_digital;
		s->insn_bits = do_wbits;
	} else {
		s->type = COMEDI_SUBD_UNUSED;
	}

	/* 8255 */
	s = &dev->subdevices[4];
	if (board->has_8255) {
		if (board->layout == LAYOUT_4020) {
			ret = subdev_8255_init(dev, s, dio_callback_4020,
					       I8255_4020_REG);
		} else {
			ret = subdev_8255_mm_init(dev, s, NULL,
						  DIO_8255_OFFSET);
		}
		if (ret)
			return ret;
	} else {
		s->type = COMEDI_SUBD_UNUSED;
	}

	/* 8 channel dio for 60xx */
	s = &dev->subdevices[5];
	if (board->layout == LAYOUT_60XX) {
		s->type = COMEDI_SUBD_DIO;
		s->subdev_flags = SDF_WRITABLE | SDF_READABLE;
		s->n_chan = 8;
		s->maxdata = 1;
		s->range_table = &range_digital;
		s->insn_config = dio_60xx_config_insn;
		s->insn_bits = dio_60xx_wbits;
	} else {
		s->type = COMEDI_SUBD_UNUSED;
	}

	/* caldac */
	s = &dev->subdevices[6];
	s->type = COMEDI_SUBD_CALIB;
	s->subdev_flags = SDF_READABLE | SDF_WRITABLE | SDF_INTERNAL;
	s->n_chan = 8;
	if (board->layout == LAYOUT_4020)
		s->maxdata = 0xfff;
	else
		s->maxdata = 0xff;
	s->insn_write = cb_pcidas64_calib_insn_write;

	ret = comedi_alloc_subdev_readback(s);
	if (ret)
		return ret;

	for (i = 0; i < s->n_chan; i++) {
		caldac_write(dev, i, s->maxdata / 2);
		s->readback[i] = s->maxdata / 2;
	}

	/* 2 channel ad8402 potentiometer */
	s = &dev->subdevices[7];
	if (board->layout == LAYOUT_64XX) {
		s->type = COMEDI_SUBD_CALIB;
		s->subdev_flags = SDF_READABLE | SDF_WRITABLE | SDF_INTERNAL;
		s->n_chan = 2;
		s->maxdata = 0xff;
		s->insn_write = cb_pcidas64_ad8402_insn_write;

		ret = comedi_alloc_subdev_readback(s);
		if (ret)
			return ret;

		for (i = 0; i < s->n_chan; i++) {
			ad8402_write(dev, i, s->maxdata / 2);
			s->readback[i] = s->maxdata / 2;
		}
	} else {
		s->type = COMEDI_SUBD_UNUSED;
	}

	/* serial EEPROM, if present */
	s = &dev->subdevices[8];
	if (readl(devpriv->plx9080_iobase + PLX_REG_CNTRL) &
	    PLX_CNTRL_EEPRESENT) {
		s->type = COMEDI_SUBD_MEMORY;
		s->subdev_flags = SDF_READABLE | SDF_INTERNAL;
		s->n_chan = 128;
		s->maxdata = 0xffff;
		s->insn_read = eeprom_read_insn;
	} else {
		s->type = COMEDI_SUBD_UNUSED;
	}

	/* user counter subd XXX */
	s = &dev->subdevices[9];
	s->type = COMEDI_SUBD_UNUSED;

	return 0;
}

static int auto_attach(struct comedi_device *dev,
		       unsigned long context)
{
	struct pci_dev *pcidev = comedi_to_pci_dev(dev);
	const struct pcidas64_board *board = NULL;
	struct pcidas64_private *devpriv;
	u32 local_range, local_decode;
	int retval;

	if (context < ARRAY_SIZE(pcidas64_boards))
		board = &pcidas64_boards[context];
	if (!board)
		return -ENODEV;
	dev->board_ptr = board;

	devpriv = comedi_alloc_devpriv(dev, sizeof(*devpriv));
	if (!devpriv)
		return -ENOMEM;

	retval = comedi_pci_enable(dev);
	if (retval)
		return retval;
	pci_set_master(pcidev);

	/* Initialize dev->board_name */
	dev->board_name = board->name;

	devpriv->main_phys_iobase = pci_resource_start(pcidev, 2);
	devpriv->dio_counter_phys_iobase = pci_resource_start(pcidev, 3);

	devpriv->plx9080_iobase = pci_ioremap_bar(pcidev, 0);
	devpriv->main_iobase = pci_ioremap_bar(pcidev, 2);
	dev->mmio = pci_ioremap_bar(pcidev, 3);

	if (!devpriv->plx9080_iobase || !devpriv->main_iobase || !dev->mmio) {
		dev_warn(dev->class_dev, "failed to remap io memory\n");
		return -ENOMEM;
	}

	/* figure out what local addresses are */
	local_range = readl(devpriv->plx9080_iobase + PLX_REG_LAS0RR) &
		      PLX_LASRR_MEM_MASK;
	local_decode = readl(devpriv->plx9080_iobase + PLX_REG_LAS0BA) &
		       local_range & PLX_LASBA_MEM_MASK;
	devpriv->local0_iobase = ((u32)devpriv->main_phys_iobase &
				  ~local_range) | local_decode;
	local_range = readl(devpriv->plx9080_iobase + PLX_REG_LAS1RR) &
		      PLX_LASRR_MEM_MASK;
	local_decode = readl(devpriv->plx9080_iobase + PLX_REG_LAS1BA) &
		       local_range & PLX_LASBA_MEM_MASK;
	devpriv->local1_iobase = ((u32)devpriv->dio_counter_phys_iobase &
				  ~local_range) | local_decode;

	retval = alloc_and_init_dma_members(dev);
	if (retval < 0)
		return retval;

	devpriv->hw_revision =
		hw_revision(dev, readw(devpriv->main_iobase + HW_STATUS_REG));
	dev_dbg(dev->class_dev, "stc hardware revision %i\n",
		devpriv->hw_revision);
	init_plx9080(dev);
	init_stc_registers(dev);

	retval = request_irq(pcidev->irq, handle_interrupt, IRQF_SHARED,
			     "cb_pcidas64", dev);
	if (retval) {
		dev_dbg(dev->class_dev, "unable to allocate irq %u\n",
			pcidev->irq);
		return retval;
	}
	dev->irq = pcidev->irq;
	dev_dbg(dev->class_dev, "irq %u\n", dev->irq);

	retval = setup_subdevices(dev);
	if (retval < 0)
		return retval;

	return 0;
}

static void detach(struct comedi_device *dev)
{
	struct pcidas64_private *devpriv = dev->private;

	if (dev->irq)
		free_irq(dev->irq, dev);
	if (devpriv) {
		if (devpriv->plx9080_iobase) {
			disable_plx_interrupts(dev);
			iounmap(devpriv->plx9080_iobase);
		}
		if (devpriv->main_iobase)
			iounmap(devpriv->main_iobase);
		if (dev->mmio)
			iounmap(dev->mmio);
	}
	comedi_pci_disable(dev);
	cb_pcidas64_free_dma(dev);
}

static struct comedi_driver cb_pcidas64_driver = {
	.driver_name	= "cb_pcidas64",
	.module		= THIS_MODULE,
	.auto_attach	= auto_attach,
	.detach		= detach,
};

static int cb_pcidas64_pci_probe(struct pci_dev *dev,
				 const struct pci_device_id *id)
{
	return comedi_pci_auto_config(dev, &cb_pcidas64_driver,
				      id->driver_data);
}

static const struct pci_device_id cb_pcidas64_pci_table[] = {
	{ PCI_VDEVICE(CB, 0x001d), BOARD_PCIDAS6402_16 },
	{ PCI_VDEVICE(CB, 0x001e), BOARD_PCIDAS6402_12 },
	{ PCI_VDEVICE(CB, 0x0035), BOARD_PCIDAS64_M1_16 },
	{ PCI_VDEVICE(CB, 0x0036), BOARD_PCIDAS64_M2_16 },
	{ PCI_VDEVICE(CB, 0x0037), BOARD_PCIDAS64_M3_16 },
	{ PCI_VDEVICE(CB, 0x0052), BOARD_PCIDAS4020_12 },
	{ PCI_VDEVICE(CB, 0x005d), BOARD_PCIDAS6023 },
	{ PCI_VDEVICE(CB, 0x005e), BOARD_PCIDAS6025 },
	{ PCI_VDEVICE(CB, 0x005f), BOARD_PCIDAS6030 },
	{ PCI_VDEVICE(CB, 0x0060), BOARD_PCIDAS6031 },
	{ PCI_VDEVICE(CB, 0x0061), BOARD_PCIDAS6032 },
	{ PCI_VDEVICE(CB, 0x0062), BOARD_PCIDAS6033 },
	{ PCI_VDEVICE(CB, 0x0063), BOARD_PCIDAS6034 },
	{ PCI_VDEVICE(CB, 0x0064), BOARD_PCIDAS6035 },
	{ PCI_VDEVICE(CB, 0x0065), BOARD_PCIDAS6040 },
	{ PCI_VDEVICE(CB, 0x0066), BOARD_PCIDAS6052 },
	{ PCI_VDEVICE(CB, 0x0067), BOARD_PCIDAS6070 },
	{ PCI_VDEVICE(CB, 0x0068), BOARD_PCIDAS6071 },
	{ PCI_VDEVICE(CB, 0x006f), BOARD_PCIDAS6036 },
	{ PCI_VDEVICE(CB, 0x0078), BOARD_PCIDAS6013 },
	{ PCI_VDEVICE(CB, 0x0079), BOARD_PCIDAS6014 },
	{ 0 }
};
MODULE_DEVICE_TABLE(pci, cb_pcidas64_pci_table);

static struct pci_driver cb_pcidas64_pci_driver = {
	.name		= "cb_pcidas64",
	.id_table	= cb_pcidas64_pci_table,
	.probe		= cb_pcidas64_pci_probe,
	.remove		= comedi_pci_auto_unconfig,
};
module_comedi_pci_driver(cb_pcidas64_driver, cb_pcidas64_pci_driver);

MODULE_AUTHOR("Comedi https://www.comedi.org");
MODULE_DESCRIPTION("Comedi low-level driver");
MODULE_LICENSE("GPL");