staging: comedi: das6402: rewrite broken driver

This driver is _really_ broken.

It initializes an analog input subdevice that only has a (*cancel)
function. It also does a request_irq() to hookup an interrupt handler
using it->options[0] as the IRQ. This option is actually the base
address of the I/O region used by the board. If the interrupt handler
actually did get hooked up, the rest of the code assumes that IRQ 10
is being used.

Rewrite the driver to properly support the hardware.

The DAS6402-12/16 boards have 64 single-ended / 32 differential analog
inputs, 2 analog outputs, 8 digital inputs, and 8 digital outputs. Add
proper support for these subdevices.

Stub in the analog input async command support.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/comedi/drivers/das6402.c

 /*
-   Some comments on the code..
-
-   - it shouldn't be necessary to use outb_p().
-
-   - ignoreirq creates a race condition.  It needs to be fixed.
-
+ * das6402.c
+ * Comedi driver for DAS6402 compatible boards
+ * Copyright(c) 2014 H Hartley Sweeten <hsweeten@visionengravers.com>
+ *
+ * Rewrite of an experimental driver by:
+ * Copyright (C) 1999 Oystein Svendsen <svendsen@pvv.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
  */
 
 /*
-   comedi/drivers/das6402.c
-   An experimental driver for Computerboards' DAS6402 I/O card
+ * Driver: das6402
+ * Description: Keithley Metrabyte DAS6402 (& compatibles)
+ * Devices: (Keithley Metrabyte) DAS6402-12 (das6402-12)
+ *	    (Keithley Metrabyte) DAS6402-16 (das6402-16)
+ * Author: H Hartley Sweeten <hsweeten@visionengravers.com>
+ * Updated: Fri, 14 Mar 2014 10:18:43 -0700
+ * Status: unknown
+ *
+ * Configuration Options:
+ *   [0] - I/O base address
+ *   [1] - IRQ (optional, needed for async command support)
+ */
 
-   Copyright (C) 1999 Oystein Svendsen <svendsen@pvv.org>
+#include <linux/module.h>
+#include <linux/interrupt.h>
 
-   This program is free software; you can redistribute it and/or modify
-   it under the terms of the GNU General Public License as published by
-   the Free Software Foundation; either version 2 of the License, or
-   (at your option) any later version.
+#include "../comedidev.h"
+#include "8253.h"
 
-   This program is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-   GNU General Public License for more details.
- */
 /*
-Driver: das6402
-Description: Keithley Metrabyte DAS6402 (& compatibles)
-Author: Oystein Svendsen <svendsen@pvv.org>
-Status: bitrotten
-Devices: [Keithley Metrabyte] DAS6402 (das6402)
+ * Register I/O map
+ */
+#define DAS6402_AI_DATA_REG		0x00
+#define DAS6402_AI_MUX_REG		0x02
+#define DAS6402_AI_MUX_LO(x)		(((x) & 0x3f) << 0)
+#define DAS6402_AI_MUX_HI(x)		(((x) & 0x3f) << 8)
+#define DAS6402_DI_DO_REG		0x03
+#define DAS6402_AO_DATA_REG(x)		(0x04 + ((x) * 2))
+#define DAS6402_AO_LSB_REG(x)		(0x04 + ((x) * 2))
+#define DAS6402_AO_MSB_REG(x)		(0x05 + ((x) * 2))
+#define DAS6402_STATUS_REG		0x08
+#define DAS6402_STATUS_FFNE		(1 << 0)
+#define DAS6402_STATUS_FHALF		(1 << 1)
+#define DAS6402_STATUS_FFULL		(1 << 2)
+#define DAS6402_STATUS_XINT		(1 << 3)
+#define DAS6402_STATUS_INT		(1 << 4)
+#define DAS6402_STATUS_XTRIG		(1 << 5)
+#define DAS6402_STATUS_INDGT		(1 << 6)
+#define DAS6402_STATUS_10MHZ		(1 << 7)
+#define DAS6402_STATUS_W_CLRINT		(1 << 0)
+#define DAS6402_STATUS_W_CLRXTR		(1 << 1)
+#define DAS6402_STATUS_W_CLRXIN		(1 << 2)
+#define DAS6402_STATUS_W_EXTEND		(1 << 4)
+#define DAS6402_STATUS_W_ARMED		(1 << 5)
+#define DAS6402_STATUS_W_POSTMODE	(1 << 6)
+#define DAS6402_STATUS_W_10MHZ		(1 << 7)
+#define DAS6402_CTRL_REG		0x09
+#define DAS6402_CTRL_SOFT_TRIG		(0 << 0)
+#define DAS6402_CTRL_EXT_FALL_TRIG	(1 << 0)
+#define DAS6402_CTRL_EXT_RISE_TRIG	(2 << 0)
+#define DAS6402_CTRL_PACER_TRIG		(3 << 0)
+#define DAS6402_CTRL_BURSTEN		(1 << 2)
+#define DAS6402_CTRL_XINTE		(1 << 3)
+#define DAS6402_CTRL_IRQ(x)		((x) << 4)
+#define DAS6402_CTRL_INTE		(1 << 7)
+#define DAS6402_TRIG_REG		0x0a
+#define DAS6402_TRIG_TGEN		(1 << 0)
+#define DAS6402_TRIG_TGSEL		(1 << 1)
+#define DAS6402_TRIG_TGPOL		(1 << 2)
+#define DAS6402_TRIG_PRETRIG		(1 << 3)
+#define DAS6402_AO_RANGE(_chan, _range)	((_range) << ((_chan) ? 6 : 4))
+#define DAS6402_AO_RANGE_MASK(_chan)	(3 << ((_chan) ? 6 : 4))
+#define DAS6402_MODE_REG		0x0b
+#define DAS6402_MODE_RANGE(x)		((x) << 0)
+#define DAS6402_MODE_POLLED		(0 << 2)
+#define DAS6402_MODE_FIFONEPTY		(1 << 2)
+#define DAS6402_MODE_FIFOHFULL		(2 << 2)
+#define DAS6402_MODE_EOB		(3 << 2)
+#define DAS6402_MODE_ENHANCED		(1 << 4)
+#define DAS6402_MODE_SE			(1 << 5)
+#define DAS6402_MODE_UNI		(1 << 6)
+#define DAS6402_MODE_DMA1		(0 << 7)
+#define DAS6402_MODE_DMA3		(1 << 7)
+#define DAS6402_TIMER_BASE		0x0c
+
+static const struct comedi_lrange das6402_ai_ranges = {
+	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)
+	}
+};
 
-This driver has suffered bitrot.
-*/
+/*
+ * Analog output ranges are programmable on the DAS6402/12.
+ * For the DAS6402/16 the range bits have no function, the
+ * DAC ranges are selected by switches on the board.
+ */
+static const struct comedi_lrange das6402_ao_ranges = {
+	4, {
+		BIP_RANGE(5),
+		BIP_RANGE(10),
+		UNI_RANGE(5),
+		UNI_RANGE(10)
+	}
+};
 
-#include <linux/module.h>
-#include <linux/interrupt.h>
-#include "../comedidev.h"
+struct das6402_boardinfo {
+	const char *name;
+	unsigned int maxdata;
+};
 
-#define DAS6402_SIZE 16
-
-#define N_WORDS (3000*64)
-
-#define STOP    0
-#define START   1
-
-#define SCANL 0x3f00
-#define BYTE unsigned char
-#define WORD unsigned short
-
-/*----- register 8 ----*/
-#define CLRINT 0x01
-#define CLRXTR 0x02
-#define CLRXIN 0x04
-#define EXTEND 0x10
-#define ARMED 0x20		/* enable conting of post sample conv */
-#define POSTMODE 0x40
-#define MHZ 0x80		/* 10 MHz clock */
-/*---------------------*/
-
-/*----- register 9 ----*/
-#define IRQ (0x04 << 4)		/* these two are                         */
-#define IRQV 10			/*               dependent on each other */
-
-#define CONVSRC 0x03		/* trig src is Intarnal pacer */
-#define BURSTEN 0x04		/* enable burst */
-#define XINTE 0x08		/* use external int. trig */
-#define INTE 0x80		/* enable analog interrupts */
-/*---------------------*/
-
-/*----- register 10 ---*/
-#define TGEN 0x01		/* Use pin DI1 for externl trigging? */
-#define TGSEL 0x02		/* Use edge triggering */
-#define TGPOL 0x04		/* active edge is falling */
-#define PRETRIG 0x08		/* pretrig */
-/*---------------------*/
-
-/*----- register 11 ---*/
-#define EOB 0x0c
-#define FIFOHFULL 0x08
-#define GAIN 0x01
-#define FIFONEPTY 0x04
-#define MODE 0x10
-#define SEM 0x20
-#define BIP 0x40
-/*---------------------*/
-
-#define M0 0x00
-#define M2 0x04
-
-#define	C0 0x00
-#define	C1 0x40
-#define	C2 0x80
-#define	RWLH 0x30
+struct das6402_boardinfo das6402_boards[] = {
+	{
+		.name		= "das6402-12",
+		.maxdata	= 0x0fff,
+	}, {
+		.name		= "das6402-16",
+		.maxdata	= 0xffff,
+	},
+};
 
 struct das6402_private {
-	int ai_bytes_to_read;
+	unsigned int irq;
+
+	unsigned int count;
+	unsigned int divider1;
+	unsigned int divider2;
 
-	int das6402_ignoreirq;
+	unsigned int ao_range;
+	unsigned int ao_readback[2];
 };
 
-static void das6402_ai_fifo_dregs(struct comedi_device *dev,
-				  struct comedi_subdevice *s)
+static void das6402_set_mode(struct comedi_device *dev,
+			     unsigned int mode)
 {
-	while (1) {
-		if (!(inb(dev->iobase + 8) & 0x01))
-			return;
-		comedi_buf_put(s->async, inw(dev->iobase));
-	}
+	outb(DAS6402_MODE_ENHANCED | mode, dev->iobase + DAS6402_MODE_REG);
 }
 
-static void das6402_setcounter(struct comedi_device *dev)
+static void das6402_set_extended(struct comedi_device *dev,
+				 unsigned int val)
 {
-	BYTE p;
-	unsigned short ctrlwrd;
-
-	/* set up counter0 first, mode 0 */
-	p = M0 | C0 | RWLH;
-	outb_p(p, dev->iobase + 15);
-	ctrlwrd = 2000;
-	p = (BYTE) (0xff & ctrlwrd);
-	outb_p(p, dev->iobase + 12);
-	p = (BYTE) (0xff & (ctrlwrd >> 8));
-	outb_p(p, dev->iobase + 12);
-
-	/* set up counter1, mode 2 */
-	p = M2 | C1 | RWLH;
-	outb_p(p, dev->iobase + 15);
-	ctrlwrd = 10;
-	p = (BYTE) (0xff & ctrlwrd);
-	outb_p(p, dev->iobase + 13);
-	p = (BYTE) (0xff & (ctrlwrd >> 8));
-	outb_p(p, dev->iobase + 13);
-
-	/* set up counter1, mode 2 */
-	p = M2 | C2 | RWLH;
-	outb_p(p, dev->iobase + 15);
-	ctrlwrd = 1000;
-	p = (BYTE) (0xff & ctrlwrd);
-	outb_p(p, dev->iobase + 14);
-	p = (BYTE) (0xff & (ctrlwrd >> 8));
-	outb_p(p, dev->iobase + 14);
+	outb(DAS6402_STATUS_W_EXTEND, dev->iobase + DAS6402_STATUS_REG);
+	outb(DAS6402_STATUS_W_EXTEND | val, dev->iobase + DAS6402_STATUS_REG);
+	outb(val, dev->iobase + DAS6402_STATUS_REG);
 }
 
-static irqreturn_t intr_handler(int irq, void *d)
+static void das6402_clear_all_interrupts(struct comedi_device *dev)
+{
+	outb(DAS6402_STATUS_W_CLRINT |
+	     DAS6402_STATUS_W_CLRXTR |
+	     DAS6402_STATUS_W_CLRXIN, dev->iobase + DAS6402_STATUS_REG);
+}
+
+static void das6402_ai_clear_eoc(struct comedi_device *dev)
+{
+	outb(DAS6402_STATUS_W_CLRINT, dev->iobase + DAS6402_STATUS_REG);
+}
+
+static void das6402_enable_counter(struct comedi_device *dev, bool load)
 {
-	struct comedi_device *dev = d;
 	struct das6402_private *devpriv = dev->private;
-	struct comedi_subdevice *s = &dev->subdevices[0];
+	unsigned long timer_iobase = dev->iobase + DAS6402_TIMER_BASE;
 
-	if (!dev->attached || devpriv->das6402_ignoreirq) {
-		dev_warn(dev->class_dev, "BUG: spurious interrupt\n");
-		return IRQ_HANDLED;
-	}
+	if (load) {
+		i8254_set_mode(timer_iobase, 0, 0, I8254_MODE0 | I8254_BINARY);
+		i8254_set_mode(timer_iobase, 0, 1, I8254_MODE2 | I8254_BINARY);
+		i8254_set_mode(timer_iobase, 0, 2, I8254_MODE2 | I8254_BINARY);
 
-	das6402_ai_fifo_dregs(dev, s);
+		i8254_write(timer_iobase, 0, 0, devpriv->count);
+		i8254_write(timer_iobase, 0, 1, devpriv->divider1);
+		i8254_write(timer_iobase, 0, 2, devpriv->divider2);
 
-	if (s->async->buf_write_count >= devpriv->ai_bytes_to_read) {
-		outw_p(SCANL, dev->iobase + 2);	/* clears the fifo */
-		outb(0x07, dev->iobase + 8);	/* clears all flip-flops */
-		s->async->events |= COMEDI_CB_EOA;
-		comedi_event(dev, s);
+	} else {
+		i8254_set_mode(timer_iobase, 0, 0, I8254_MODE0 | I8254_BINARY);
+		i8254_set_mode(timer_iobase, 0, 1, I8254_MODE0 | I8254_BINARY);
+		i8254_set_mode(timer_iobase, 0, 2, I8254_MODE0 | I8254_BINARY);
 	}
+}
 
-	outb(0x01, dev->iobase + 8);	/* clear only the interrupt flip-flop */
+static irqreturn_t das6402_interrupt(int irq, void *d)
+{
+	struct comedi_device *dev = d;
+
+	das6402_clear_all_interrupts(dev);
 
-	comedi_event(dev, s);
 	return IRQ_HANDLED;
 }
 
-#if 0
-static void das6402_ai_fifo_read(struct comedi_device *dev, short *data, int n)
+static int das6402_ai_cmd(struct comedi_device *dev,
+			  struct comedi_subdevice *s)
 {
-	int i;
+	return -EINVAL;
+}
 
-	for (i = 0; i < n; i++)
-		data[i] = inw(dev->iobase);
+static int das6402_ai_cmdtest(struct comedi_device *dev,
+			      struct comedi_subdevice *s,
+			      struct comedi_cmd *cmd)
+{
+	return -EINVAL;
 }
-#endif
 
 static int das6402_ai_cancel(struct comedi_device *dev,
 			     struct comedi_subdevice *s)
+{
+	outb(DAS6402_CTRL_SOFT_TRIG, dev->iobase + DAS6402_CTRL_REG);
+
+	return 0;
+}
+
+static void das6402_ai_soft_trig(struct comedi_device *dev)
+{
+	outw(0, dev->iobase + DAS6402_AI_DATA_REG);
+}
+
+static int das6402_ai_eoc(struct comedi_device *dev,
+			  struct comedi_subdevice *s,
+			  struct comedi_insn *insn,
+			  unsigned long context)
+{
+	unsigned int status;
+
+	status = inb(dev->iobase + DAS6402_STATUS_REG);
+	if (status & DAS6402_STATUS_FFNE)
+		return 0;
+	return -EBUSY;
+}
+
+static int das6402_ai_insn_read(struct comedi_device *dev,
+				struct comedi_subdevice *s,
+				struct comedi_insn *insn,
+				unsigned int *data)
+{
+	unsigned int chan = CR_CHAN(insn->chanspec);
+	unsigned int range = CR_RANGE(insn->chanspec);
+	unsigned int aref = CR_AREF(insn->chanspec);
+	unsigned int val;
+	int ret;
+	int i;
+
+	val = DAS6402_MODE_RANGE(range) | DAS6402_MODE_POLLED;
+	if (aref == AREF_DIFF) {
+		if (chan > s->n_chan / 2)
+			return -EINVAL;
+	} else {
+		val |= DAS6402_MODE_SE;
+	}
+	if (comedi_range_is_unipolar(s, range))
+		val |= DAS6402_MODE_UNI;
+
+	/* enable software conversion trigger */
+	outb(DAS6402_CTRL_SOFT_TRIG, dev->iobase + DAS6402_CTRL_REG);
+
+	das6402_set_mode(dev, val);
+
+	/* load the mux for single channel conversion */
+	outw(DAS6402_AI_MUX_HI(chan) | DAS6402_AI_MUX_LO(chan),
+	     dev->iobase + DAS6402_AI_MUX_REG);
+
+	for (i = 0; i < insn->n; i++) {
+		das6402_ai_clear_eoc(dev);
+		das6402_ai_soft_trig(dev);
+
+		ret = comedi_timeout(dev, s, insn, das6402_ai_eoc, 0);
+		if (ret)
+			break;
+
+		val = inw(dev->iobase + DAS6402_AI_DATA_REG);
+
+		if (s->maxdata == 0x0fff)
+			val >>= 4;
+
+		data[i] = val;
+	}
+
+	das6402_ai_clear_eoc(dev);
+
+	return insn->n;
+}
+
+static int das6402_ao_insn_write(struct comedi_device *dev,
+				 struct comedi_subdevice *s,
+				 struct comedi_insn *insn,
+				 unsigned int *data)
 {
 	struct das6402_private *devpriv = dev->private;
+	unsigned int chan = CR_CHAN(insn->chanspec);
+	unsigned int range = CR_RANGE(insn->chanspec);
+	unsigned int val;
+	int i;
+
+	/* set the range for this channel */
+	val = devpriv->ao_range;
+	val &= ~DAS6402_AO_RANGE_MASK(chan);
+	val |= DAS6402_AO_RANGE(chan, range);
+	if (val != devpriv->ao_range) {
+		devpriv->ao_range = val;
+		outb(val, dev->iobase + DAS6402_TRIG_REG);
+	}
 
 	/*
-	 *  This function should reset the board from whatever condition it
-	 *  is in (i.e., acquiring data), to a non-active state.
+	 * The DAS6402/16 has a jumper to select either individual
+	 * update (UPDATE) or simultaneous updating (XFER) of both
+	 * DAC's. In UPDATE mode, when the MSB is written, that DAC
+	 * is updated. In XFER mode, after both DAC's are loaded,
+	 * a read cycle of any DAC register will update both DAC's
+	 * simultaneously.
+	 *
+	 * If you have XFER mode enabled a (*insn_read) will need
+	 * to be performed in order to update the DAC's with the
+	 * last value written.
 	 */
+	for (i = 0; i < insn->n; i++) {
+		val = data[i];
+
+		devpriv->ao_readback[chan] = val;
+
+		if (s->maxdata == 0x0fff) {
+			/*
+			 * DAS6402/12 has the two 8-bit DAC registers, left
+			 * justified (the 4 LSB bits are don't care). Data
+			 * can be written as one word.
+			 */
+			val <<= 4;
+			outw(val, dev->iobase + DAS6402_AO_DATA_REG(chan));
+		} else {
+			/*
+			 * DAS6402/16 uses both 8-bit DAC registers and needs
+			 * to be written LSB then MSB.
+			 */
+			outb(val & 0xff,
+			     dev->iobase + DAS6402_AO_LSB_REG(chan));
+			outb((val >> 8) & 0xff,
+			     dev->iobase + DAS6402_AO_LSB_REG(chan));
+		}
+	}
 
-	devpriv->das6402_ignoreirq = 1;
-	dev_dbg(dev->class_dev, "Stopping acquisition\n");
-	devpriv->das6402_ignoreirq = 1;
-	outb_p(0x02, dev->iobase + 10);	/* disable external trigging */
-	outw_p(SCANL, dev->iobase + 2);	/* resets the card fifo */
-	outb_p(0, dev->iobase + 9);	/* disables interrupts */
-
-	outw_p(SCANL, dev->iobase + 2);
-
-	return 0;
+	return insn->n;
 }
 
-#ifdef unused
-static int das6402_ai_mode2(struct comedi_device *dev,
-			    struct comedi_subdevice *s, comedi_trig *it)
+static int das6402_ao_insn_read(struct comedi_device *dev,
+				struct comedi_subdevice *s,
+				struct comedi_insn *insn,
+				unsigned int *data)
 {
 	struct das6402_private *devpriv = dev->private;
+	unsigned int chan = CR_CHAN(insn->chanspec);
+	int i;
 
-	devpriv->das6402_ignoreirq = 1;
-	dev_dbg(dev->class_dev, "Starting acquisition\n");
-	outb_p(0x03, dev->iobase + 10);	/* enable external trigging */
-	outw_p(SCANL, dev->iobase + 2);	/* resets the card fifo */
-	outb_p(IRQ | CONVSRC | BURSTEN | INTE, dev->iobase + 9);
+	/*
+	 * If XFER mode is enabled, reading any DAC register
+	 * will update both DAC's simultaneously.
+	 */
+	inw(dev->iobase + DAS6402_AO_LSB_REG(chan));
 
-	devpriv->ai_bytes_to_read = it->n * sizeof(short);
+	for (i = 0; i < insn->n; i++)
+		data[i] = devpriv->ao_readback[chan];
 
-	/* um... ignoreirq is a nasty race condition */
-	devpriv->das6402_ignoreirq = 0;
+	return insn->n;
+}
 
-	outw_p(SCANL, dev->iobase + 2);
+static int das6402_di_insn_bits(struct comedi_device *dev,
+				struct comedi_subdevice *s,
+				struct comedi_insn *insn,
+				unsigned int *data)
+{
+	data[1] = inb(dev->iobase + DAS6402_DI_DO_REG);
 
-	return 0;
+	return insn->n;
 }
-#endif
 
-static int board_init(struct comedi_device *dev)
+static int das6402_do_insn_bits(struct comedi_device *dev,
+				struct comedi_subdevice *s,
+				struct comedi_insn *insn,
+				unsigned int *data)
 {
-	struct das6402_private *devpriv = dev->private;
-	BYTE b;
+	if (comedi_dio_update_state(s, data))
+		outb(s->state, dev->iobase + DAS6402_DI_DO_REG);
 
-	devpriv->das6402_ignoreirq = 1;
+	data[1] = s->state;
 
-	outb(0x07, dev->iobase + 8);
+	return insn->n;
+}
 
-	/* register 11  */
-	outb_p(MODE, dev->iobase + 11);
-	b = BIP | SEM | MODE | GAIN | FIFOHFULL;
-	outb_p(b, dev->iobase + 11);
+static void das6402_reset(struct comedi_device *dev)
+{
+	struct das6402_private *devpriv = dev->private;
 
-	/* register 8   */
-	outb_p(EXTEND, dev->iobase + 8);
-	b = EXTEND | MHZ;
-	outb_p(b, dev->iobase + 8);
-	b = MHZ | CLRINT | CLRXTR | CLRXIN;
-	outb_p(b, dev->iobase + 8);
+	/* enable "Enhanced" mode */
+	outb(DAS6402_MODE_ENHANCED, dev->iobase + DAS6402_MODE_REG);
 
-	/* register 9    */
-	b = IRQ | CONVSRC | BURSTEN | INTE;
-	outb_p(b, dev->iobase + 9);
+	/* enable 10MHz pacer clock */
+	das6402_set_extended(dev, DAS6402_STATUS_W_10MHZ);
 
-	/* register 10   */
-	b = TGSEL | TGEN;
-	outb_p(b, dev->iobase + 10);
+	/* enable software conversion trigger */
+	outb(DAS6402_CTRL_SOFT_TRIG, dev->iobase + DAS6402_CTRL_REG);
 
-	b = 0x07;
-	outb_p(b, dev->iobase + 8);
+	/* default ADC to single-ended unipolar 10V inputs */
+	das6402_set_mode(dev, DAS6402_MODE_RANGE(0) |
+			      DAS6402_MODE_POLLED |
+			      DAS6402_MODE_SE |
+			      DAS6402_MODE_UNI);
 
-	das6402_setcounter(dev);
+	/* default mux for single channel conversion (channel 0) */
+	outw(DAS6402_AI_MUX_HI(0) | DAS6402_AI_MUX_LO(0),
+	     dev->iobase + DAS6402_AI_MUX_REG);
 
-	outw_p(SCANL, dev->iobase + 2);	/* reset card fifo */
+	/* set both DAC's for unipolar 5V output range */
+	devpriv->ao_range = DAS6402_AO_RANGE(0, 2) | DAS6402_AO_RANGE(1, 2);
+	outb(devpriv->ao_range, dev->iobase + DAS6402_TRIG_REG);
 
-	devpriv->das6402_ignoreirq = 0;
+	/* set both DAC's to 0V */
+	outw(0, dev->iobase + DAS6402_AO_DATA_REG(0));
+	outw(0, dev->iobase + DAS6402_AO_DATA_REG(0));
+	inw(dev->iobase + DAS6402_AO_LSB_REG(0));
 
-	return 0;
+	das6402_enable_counter(dev, false);
+
+	/* set all digital outputs low */
+	outb(0, dev->iobase + DAS6402_DI_DO_REG);
+
+	das6402_clear_all_interrupts(dev);
 }
 
 static int das6402_attach(struct comedi_device *dev,
 			  struct comedi_devconfig *it)
 {
+	const struct das6402_boardinfo *board = comedi_board(dev);
 	struct das6402_private *devpriv;
-	unsigned int irq;
-	int ret;
 	struct comedi_subdevice *s;
-
-	ret = comedi_request_region(dev, it->options[0], DAS6402_SIZE);
-	if (ret)
-		return ret;
-
-	irq = it->options[0];
-	dev_dbg(dev->class_dev, "( irq = %u )\n", irq);
-	ret = request_irq(irq, intr_handler, 0, "das6402", dev);
-	if (ret < 0)
-		return ret;
-
-	dev->irq = irq;
+	int ret;
 
 	devpriv = comedi_alloc_devpriv(dev, sizeof(*devpriv));
 	if (!devpriv)
 		return -ENOMEM;
 
-	ret = comedi_alloc_subdevices(dev, 1);
+	ret = comedi_request_region(dev, it->options[0], 0x10);
 	if (ret)
 		return ret;
 
-	/* ai subdevice */
+	das6402_reset(dev);
+
+	/* IRQs 2,3,5,6,7, 10,11,15 are valid for "enhanced" mode */
+	if ((1 << it->options[1]) & 0x8cec) {
+		ret = request_irq(it->options[1], das6402_interrupt, 0,
+				  dev->board_name, dev);
+		if (ret == 0) {
+			dev->irq = it->options[1];
+
+			switch (dev->irq) {
+			case 10:
+				devpriv->irq = 4;
+				break;
+			case 11:
+				devpriv->irq = 1;
+				break;
+			case 15:
+				devpriv->irq = 6;
+				break;
+			default:
+				devpriv->irq = dev->irq;
+				break;
+			}
+		}
+	}
+
+	ret = comedi_alloc_subdevices(dev, 4);
+	if (ret)
+		return ret;
+
+	/* Analog Input subdevice */
 	s = &dev->subdevices[0];
-	s->type = COMEDI_SUBD_AI;
-	s->subdev_flags = SDF_READABLE | SDF_GROUND;
-	s->n_chan = 8;
-	/* s->trig[2]=das6402_ai_mode2; */
-	s->cancel = das6402_ai_cancel;
-	s->maxdata = (1 << 12) - 1;
-	s->len_chanlist = 16;	/* ? */
-	s->range_table = &range_unknown;
+	s->type		= COMEDI_SUBD_AI;
+	s->subdev_flags	= SDF_READABLE | SDF_GROUND | SDF_DIFF;
+	s->n_chan	= 64;
+	s->maxdata	= board->maxdata;
+	s->range_table	= &das6402_ai_ranges;
+	s->insn_read	= das6402_ai_insn_read;
+	if (dev->irq) {
+		dev->read_subdev = s;
+		s->subdev_flags	|= SDF_CMD_READ;
+		s->len_chanlist	= s->n_chan;
+		s->do_cmdtest	= das6402_ai_cmdtest;
+		s->do_cmd	= das6402_ai_cmd;
+		s->cancel	= das6402_ai_cancel;
+	}
 
-	board_init(dev);
+	/* Analog Output subdevice */
+	s = &dev->subdevices[1];
+	s->type		= COMEDI_SUBD_AO;
+	s->subdev_flags	= SDF_WRITEABLE;
+	s->n_chan	= 2;
+	s->maxdata	= board->maxdata;
+	s->range_table	= &das6402_ao_ranges;
+	s->insn_write	= das6402_ao_insn_write;
+	s->insn_read	= das6402_ao_insn_read;
+
+	/* Digital Input subdevice */
+	s = &dev->subdevices[2];
+	s->type		= COMEDI_SUBD_DI;
+	s->subdev_flags	= SDF_READABLE;
+	s->n_chan	= 8;
+	s->maxdata	= 1;
+	s->range_table	= &range_digital;
+	s->insn_bits	= das6402_di_insn_bits;
+
+	/* Digital Input subdevice */
+	s = &dev->subdevices[3];
+	s->type		= COMEDI_SUBD_DO;
+	s->subdev_flags	= SDF_WRITEABLE;
+	s->n_chan	= 8;
+	s->maxdata	= 1;
+	s->range_table	= &range_digital;
+	s->insn_bits	= das6402_do_insn_bits;
 
 	return 0;
 }
@@ -313,9 +536,12 @@ static struct comedi_driver das6402_driver = {
 	.module		= THIS_MODULE,
 	.attach		= das6402_attach,
 	.detach		= comedi_legacy_detach,
+	.board_name	= &das6402_boards[0].name,
+	.num_names	= ARRAY_SIZE(das6402_boards),
+	.offset		= sizeof(struct das6402_boardinfo),
 };
 module_comedi_driver(das6402_driver)
 
-MODULE_AUTHOR("Comedi http://www.comedi.org");
-MODULE_DESCRIPTION("Comedi low-level driver");
+MODULE_AUTHOR("H Hartley Sweeten <hsweeten@visionengravers.com>");
+MODULE_DESCRIPTION("Comedi driver for DAS6402 compatible boards");
 MODULE_LICENSE("GPL");