]> www.pilppa.org Git - linux-2.6-omap-h63xx.git/blobdiff - drivers/staging/comedi/drivers/pcmmio.c
Merge branch 'omap-pool'
[linux-2.6-omap-h63xx.git] / drivers / staging / comedi / drivers / pcmmio.c
diff --git a/drivers/staging/comedi/drivers/pcmmio.c b/drivers/staging/comedi/drivers/pcmmio.c
new file mode 100644 (file)
index 0000000..01e40f1
--- /dev/null
@@ -0,0 +1,1333 @@
+/*
+    comedi/drivers/pcmmio.c
+    Driver for Winsystems PC-104 based multifunction IO board.
+
+    COMEDI - Linux Control and Measurement Device Interface
+    Copyright (C) 2007 Calin A. Culianu <calin@ajvar.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.
+
+    You should have received a copy of the GNU General Public License
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+*/
+/*
+Driver: pcmmio
+Description: A driver for the PCM-MIO multifunction board
+Devices: [Winsystems] PCM-MIO (pcmmio)
+Author: Calin Culianu <calin@ajvar.org>
+Updated: Wed, May 16 2007 16:21:10 -0500
+Status: works
+
+A driver for the relatively new PCM-MIO multifunction board from
+Winsystems.  This board is a PC-104 based I/O board.  It contains
+four subdevices:
+  subdevice 0 - 16 channels of 16-bit AI
+  subdevice 1 - 8 channels of 16-bit AO
+  subdevice 2 - first 24 channels of the 48 channel of DIO (with edge-triggered interrupt support)
+  subdevice 3 - last 24 channels of the 48 channel DIO (no interrupt support for this bank of channels)
+
+  Some notes:
+
+  Synchronous reads and writes are the only things implemented for AI and AO,
+  even though the hardware itself can do streaming acquisition, etc.  Anyone
+  want to add asynchronous I/O for AI/AO as a feature?  Be my guest...
+
+  Asynchronous I/O for the DIO subdevices *is* implemented, however!  They are
+  basically edge-triggered interrupts for any configuration of the first
+  24 DIO-lines.
+
+  Also note that this interrupt support is untested.
+
+  A few words about edge-detection IRQ support (commands on DIO):
+
+  * To use edge-detection IRQ support for the DIO subdevice, pass the IRQ
+    of the board to the comedi_config command.  The board IRQ is not jumpered
+    but rather configured through software, so any IRQ from 1-15 is OK.
+
+  * Due to the genericity of the comedi API, you need to create a special
+    comedi_command in order to use edge-triggered interrupts for DIO.
+
+  * Use comedi_commands with TRIG_NOW.  Your callback will be called each
+    time an edge is detected on the specified DIO line(s), and the data
+    values will be two sample_t's, which should be concatenated to form
+    one 32-bit unsigned int.  This value is the mask of channels that had
+    edges detected from your channel list.  Note that the bits positions
+    in the mask correspond to positions in your chanlist when you
+    specified the command and *not* channel id's!
+
+ *  To set the polarity of the edge-detection interrupts pass a nonzero value
+    for either CR_RANGE or CR_AREF for edge-up polarity, or a zero
+    value for both CR_RANGE and CR_AREF if you want edge-down polarity.
+
+Configuration Options:
+  [0] - I/O port base address
+  [1] - IRQ (optional -- for edge-detect interrupt support only, leave out if you don't need this feature)
+*/
+
+#include "../comedidev.h"
+#include <linux/pci.h>         /* for PCI devices */
+
+#define MIN(a,b) ( ((a) < (b)) ? (a) : (b) )
+
+/* This stuff is all from pcmuio.c -- it refers to the DIO subdevices only */
+#define CHANS_PER_PORT   8
+#define PORTS_PER_ASIC   6
+#define INTR_PORTS_PER_ASIC   3
+#define MAX_CHANS_PER_SUBDEV 24        /* number of channels per comedi subdevice */
+#define PORTS_PER_SUBDEV (MAX_CHANS_PER_SUBDEV/CHANS_PER_PORT)
+#define CHANS_PER_ASIC (CHANS_PER_PORT*PORTS_PER_ASIC)
+#define INTR_CHANS_PER_ASIC 24
+#define INTR_PORTS_PER_SUBDEV (INTR_CHANS_PER_ASIC/CHANS_PER_PORT)
+#define MAX_DIO_CHANS   (PORTS_PER_ASIC*1*CHANS_PER_PORT)
+#define MAX_ASICS       (MAX_DIO_CHANS/CHANS_PER_ASIC)
+#define SDEV_NO ((int)(s - dev->subdevices))
+#define CALC_N_DIO_SUBDEVS(nchans) ((nchans)/MAX_CHANS_PER_SUBDEV + (!!((nchans)%MAX_CHANS_PER_SUBDEV)) /*+ (nchans > INTR_CHANS_PER_ASIC ? 2 : 1)*/)
+/* IO Memory sizes */
+#define ASIC_IOSIZE (0x0B)
+#define PCMMIO48_IOSIZE ASIC_IOSIZE
+
+/* Some offsets - these are all in the 16byte IO memory offset from
+   the base address.  Note that there is a paging scheme to swap out
+   offsets 0x8-0xA using the PAGELOCK register.  See the table below.
+
+  Register(s)       Pages        R/W?        Description
+  --------------------------------------------------------------
+  REG_PORTx         All          R/W         Read/Write/Configure IO
+  REG_INT_PENDING   All          ReadOnly    Quickly see which INT_IDx has int.
+  REG_PAGELOCK      All          WriteOnly   Select a page
+  REG_POLx          Pg. 1 only   WriteOnly   Select edge-detection polarity
+  REG_ENABx         Pg. 2 only   WriteOnly   Enable/Disable edge-detect. int.
+  REG_INT_IDx       Pg. 3 only   R/W         See which ports/bits have ints.
+ */
+#define REG_PORT0 0x0
+#define REG_PORT1 0x1
+#define REG_PORT2 0x2
+#define REG_PORT3 0x3
+#define REG_PORT4 0x4
+#define REG_PORT5 0x5
+#define REG_INT_PENDING 0x6
+#define REG_PAGELOCK 0x7       /* page selector register, upper 2 bits select a page
+                                  and bits 0-5 are used to 'lock down' a particular
+                                  port above to make it readonly.  */
+#define REG_POL0 0x8
+#define REG_POL1 0x9
+#define REG_POL2 0xA
+#define REG_ENAB0 0x8
+#define REG_ENAB1 0x9
+#define REG_ENAB2 0xA
+#define REG_INT_ID0 0x8
+#define REG_INT_ID1 0x9
+#define REG_INT_ID2 0xA
+
+#define NUM_PAGED_REGS 3
+#define NUM_PAGES 4
+#define FIRST_PAGED_REG 0x8
+#define REG_PAGE_BITOFFSET 6
+#define REG_LOCK_BITOFFSET 0
+#define REG_PAGE_MASK (~((0x1<<REG_PAGE_BITOFFSET)-1))
+#define REG_LOCK_MASK ~(REG_PAGE_MASK)
+#define PAGE_POL 1
+#define PAGE_ENAB 2
+#define PAGE_INT_ID 3
+
+typedef int (*comedi_insn_fn_t) (struct comedi_device *, struct comedi_subdevice *,
+       struct comedi_insn *, unsigned int *);
+
+static int ai_rinsn(struct comedi_device *, struct comedi_subdevice *, struct comedi_insn *,
+       unsigned int *);
+static int ao_rinsn(struct comedi_device *, struct comedi_subdevice *, struct comedi_insn *,
+       unsigned int *);
+static int ao_winsn(struct comedi_device *, struct comedi_subdevice *, struct comedi_insn *,
+       unsigned int *);
+
+/*
+ * Board descriptions for two imaginary boards.  Describing the
+ * boards in this way is optional, and completely driver-dependent.
+ * Some drivers use arrays such as this, other do not.
+ */
+struct pcmmio_board {
+       const char *name;
+       const int dio_num_asics;
+       const int dio_num_ports;
+       const int total_iosize;
+       const int ai_bits;
+       const int ao_bits;
+       const int n_ai_chans;
+       const int n_ao_chans;
+       const struct comedi_lrange *ai_range_table, *ao_range_table;
+       comedi_insn_fn_t ai_rinsn, ao_rinsn, ao_winsn;
+};
+
+static const struct comedi_lrange ranges_ai =
+       { 4, {RANGE(-5., 5.), RANGE(-10., 10.), RANGE(0., 5.), RANGE(0.,
+               10.)}
+};
+
+static const struct comedi_lrange ranges_ao =
+       { 6, {RANGE(0., 5.), RANGE(0., 10.), RANGE(-5., 5.), RANGE(-10., 10.),
+       RANGE(-2.5, 2.5), RANGE(-2.5, 7.5)}
+};
+
+static const struct pcmmio_board pcmmio_boards[] = {
+       {
+             name:     "pcmmio",
+             dio_num_asics:1,
+             dio_num_ports:6,
+             total_iosize:32,
+             ai_bits:  16,
+             ao_bits:  16,
+             n_ai_chans:16,
+             n_ao_chans:8,
+             ai_range_table:&ranges_ai,
+             ao_range_table:&ranges_ao,
+             ai_rinsn:ai_rinsn,
+             ao_rinsn:ao_rinsn,
+      ao_winsn:ao_winsn},
+};
+
+/*
+ * Useful for shorthand access to the particular board structure
+ */
+#define thisboard ((const struct pcmmio_board *)dev->board_ptr)
+
+/* this structure is for data unique to this subdevice.  */
+struct pcmmio_subdev_private {
+
+       union {
+               /* for DIO: mapping of halfwords (bytes) in port/chanarray to iobase */
+               unsigned long iobases[PORTS_PER_SUBDEV];
+
+               /* for AI/AO */
+               unsigned long iobase;
+       };
+       union {
+               struct {
+
+                       /* The below is only used for intr subdevices */
+                       struct {
+                               int asic;       /* if non-negative, this subdev has an interrupt asic */
+                               int first_chan; /* if nonnegative, the first channel id for
+                                                  interrupts. */
+                               int num_asic_chans;     /* the number of asic channels in this subdev
+                                                          that have interrutps */
+                               int asic_chan;  /* if nonnegative, the first channel id with
+                                                  respect to the asic that has interrupts */
+                               int enabled_mask;       /* subdev-relative channel mask for channels
+                                                          we are interested in */
+                               int active;
+                               int stop_count;
+                               int continuous;
+                               spinlock_t spinlock;
+                       } intr;
+               } dio;
+               struct {
+                       unsigned int shadow_samples[8]; /* the last unsigned int data written */
+               } ao;
+       };
+};
+
+/* this structure is for data unique to this hardware driver.  If
+   several hardware drivers keep similar information in this structure,
+   feel free to suggest moving the variable to the struct comedi_device struct.  */
+struct pcmmio_private {
+       /* stuff for DIO */
+       struct {
+               unsigned char pagelock; /* current page and lock */
+               unsigned char pol[NUM_PAGED_REGS];      /* shadow of POLx registers */
+               unsigned char enab[NUM_PAGED_REGS];     /* shadow of ENABx registers */
+               int num;
+               unsigned long iobase;
+               unsigned int irq;
+               spinlock_t spinlock;
+       } asics[MAX_ASICS];
+       struct pcmmio_subdev_private *sprivs;
+};
+
+/*
+ * most drivers define the following macro to make it easy to
+ * access the private structure.
+ */
+#define devpriv ((struct pcmmio_private *)dev->private)
+#define subpriv ((struct pcmmio_subdev_private *)s->private)
+/*
+ * The struct comedi_driver structure tells the Comedi core module
+ * which functions to call to configure/deconfigure (attach/detach)
+ * the board, and also about the kernel module that contains
+ * the device code.
+ */
+static int pcmmio_attach(struct comedi_device * dev, struct comedi_devconfig * it);
+static int pcmmio_detach(struct comedi_device * dev);
+
+static struct comedi_driver driver = {
+      driver_name:"pcmmio",
+      module:THIS_MODULE,
+      attach:pcmmio_attach,
+      detach:pcmmio_detach,
+/* It is not necessary to implement the following members if you are
+ * writing a driver for a ISA PnP or PCI card */
+       /* Most drivers will support multiple types of boards by
+        * having an array of board structures.  These were defined
+        * in pcmmio_boards[] above.  Note that the element 'name'
+        * was first in the structure -- Comedi uses this fact to
+        * extract the name of the board without knowing any details
+        * about the structure except for its length.
+        * When a device is attached (by comedi_config), the name
+        * of the device is given to Comedi, and Comedi tries to
+        * match it by going through the list of board names.  If
+        * there is a match, the address of the pointer is put
+        * into dev->board_ptr and driver->attach() is called.
+        *
+        * Note that these are not necessary if you can determine
+        * the type of board in software.  ISA PnP, PCI, and PCMCIA
+        * devices are such boards.
+        */
+      board_name:&pcmmio_boards[0].name,
+      offset:sizeof(struct pcmmio_board),
+      num_names:sizeof(pcmmio_boards) / sizeof(struct pcmmio_board),
+};
+
+static int pcmmio_dio_insn_bits(struct comedi_device * dev, struct comedi_subdevice * s,
+       struct comedi_insn * insn, unsigned int * data);
+static int pcmmio_dio_insn_config(struct comedi_device * dev, struct comedi_subdevice * s,
+       struct comedi_insn * insn, unsigned int * data);
+
+static irqreturn_t interrupt_pcmmio(int irq, void *d PT_REGS_ARG);
+static void pcmmio_stop_intr(struct comedi_device *, struct comedi_subdevice *);
+static int pcmmio_cancel(struct comedi_device * dev, struct comedi_subdevice * s);
+static int pcmmio_cmd(struct comedi_device * dev, struct comedi_subdevice * s);
+static int pcmmio_cmdtest(struct comedi_device * dev, struct comedi_subdevice * s,
+       struct comedi_cmd * cmd);
+
+/* some helper functions to deal with specifics of this device's registers */
+static void init_asics(struct comedi_device * dev);    /* sets up/clears ASIC chips to defaults */
+static void switch_page(struct comedi_device * dev, int asic, int page);
+#ifdef notused
+static void lock_port(struct comedi_device * dev, int asic, int port);
+static void unlock_port(struct comedi_device * dev, int asic, int port);
+#endif
+
+/*
+ * Attach is called by the Comedi core to configure the driver
+ * for a particular board.  If you specified a board_name array
+ * in the driver structure, dev->board_ptr contains that
+ * address.
+ */
+static int pcmmio_attach(struct comedi_device * dev, struct comedi_devconfig * it)
+{
+       struct comedi_subdevice *s;
+       int sdev_no, chans_left, n_dio_subdevs, n_subdevs, port, asic,
+               thisasic_chanct = 0;
+       unsigned long iobase;
+       unsigned int irq[MAX_ASICS];
+
+       iobase = it->options[0];
+       irq[0] = it->options[1];
+
+       printk("comedi%d: %s: io: %lx ", dev->minor, driver.driver_name,
+               iobase);
+
+       dev->iobase = iobase;
+
+       if (!iobase || !request_region(iobase,
+                       thisboard->total_iosize, driver.driver_name)) {
+               printk("I/O port conflict\n");
+               return -EIO;
+       }
+
+/*
+ * Initialize dev->board_name.  Note that we can use the "thisboard"
+ * macro now, since we just initialized it in the last line.
+ */
+       dev->board_name = thisboard->name;
+
+/*
+ * Allocate the private structure area.  alloc_private() is a
+ * convenient macro defined in comedidev.h.
+ */
+       if (alloc_private(dev, sizeof(struct pcmmio_private)) < 0) {
+               printk("cannot allocate private data structure\n");
+               return -ENOMEM;
+       }
+
+       for (asic = 0; asic < MAX_ASICS; ++asic) {
+               devpriv->asics[asic].num = asic;
+               devpriv->asics[asic].iobase =
+                       dev->iobase + 16 + asic * ASIC_IOSIZE;
+               devpriv->asics[asic].irq = 0;   /* this gets actually set at the end of
+                                                  this function when we
+                                                  comedi_request_irqs */
+               spin_lock_init(&devpriv->asics[asic].spinlock);
+       }
+
+       chans_left = CHANS_PER_ASIC * thisboard->dio_num_asics;
+       n_dio_subdevs = CALC_N_DIO_SUBDEVS(chans_left);
+       n_subdevs = n_dio_subdevs + 2;
+       devpriv->sprivs =
+               kcalloc(n_subdevs, sizeof(struct pcmmio_subdev_private), GFP_KERNEL);
+       if (!devpriv->sprivs) {
+               printk("cannot allocate subdevice private data structures\n");
+               return -ENOMEM;
+       }
+       /*
+        * Allocate the subdevice structures.  alloc_subdevice() is a
+        * convenient macro defined in comedidev.h.
+        *
+        * Allocate 1 AI + 1 AO + 2 DIO subdevs (24 lines per DIO)
+        */
+       if (alloc_subdevices(dev, n_subdevs) < 0) {
+               printk("cannot allocate subdevice data structures\n");
+               return -ENOMEM;
+       }
+
+       /* First, AI */
+       sdev_no = 0;
+       s = dev->subdevices + sdev_no;
+       s->private = devpriv->sprivs + sdev_no;
+       s->maxdata = (1 << thisboard->ai_bits) - 1;
+       s->range_table = thisboard->ai_range_table;
+       s->subdev_flags = SDF_READABLE | SDF_GROUND | SDF_DIFF;
+       s->type = COMEDI_SUBD_AI;
+       s->n_chan = thisboard->n_ai_chans;
+       s->len_chanlist = s->n_chan;
+       s->insn_read = thisboard->ai_rinsn;
+       subpriv->iobase = dev->iobase + 0;
+       /* initialize the resource enable register by clearing it */
+       outb(0, subpriv->iobase + 3);
+       outb(0, subpriv->iobase + 4 + 3);
+
+       /* Next, AO */
+       ++sdev_no;
+       s = dev->subdevices + sdev_no;
+       s->private = devpriv->sprivs + sdev_no;
+       s->maxdata = (1 << thisboard->ao_bits) - 1;
+       s->range_table = thisboard->ao_range_table;
+       s->subdev_flags = SDF_READABLE;
+       s->type = COMEDI_SUBD_AO;
+       s->n_chan = thisboard->n_ao_chans;
+       s->len_chanlist = s->n_chan;
+       s->insn_read = thisboard->ao_rinsn;
+       s->insn_write = thisboard->ao_winsn;
+       subpriv->iobase = dev->iobase + 8;
+       /* initialize the resource enable register by clearing it */
+       outb(0, subpriv->iobase + 3);
+       outb(0, subpriv->iobase + 4 + 3);
+
+       ++sdev_no;
+       port = 0;
+       asic = 0;
+       for (; sdev_no < (int)dev->n_subdevices; ++sdev_no) {
+               int byte_no;
+
+               s = dev->subdevices + sdev_no;
+               s->private = devpriv->sprivs + sdev_no;
+               s->maxdata = 1;
+               s->range_table = &range_digital;
+               s->subdev_flags = SDF_READABLE | SDF_WRITABLE;
+               s->type = COMEDI_SUBD_DIO;
+               s->insn_bits = pcmmio_dio_insn_bits;
+               s->insn_config = pcmmio_dio_insn_config;
+               s->n_chan = MIN(chans_left, MAX_CHANS_PER_SUBDEV);
+               subpriv->dio.intr.asic = -1;
+               subpriv->dio.intr.first_chan = -1;
+               subpriv->dio.intr.asic_chan = -1;
+               subpriv->dio.intr.num_asic_chans = -1;
+               subpriv->dio.intr.active = 0;
+               s->len_chanlist = 1;
+
+               /* save the ioport address for each 'port' of 8 channels in the
+                  subdevice */
+               for (byte_no = 0; byte_no < PORTS_PER_SUBDEV; ++byte_no, ++port) {
+                       if (port >= PORTS_PER_ASIC) {
+                               port = 0;
+                               ++asic;
+                               thisasic_chanct = 0;
+                       }
+                       subpriv->iobases[byte_no] =
+                               devpriv->asics[asic].iobase + port;
+
+                       if (thisasic_chanct <
+                               CHANS_PER_PORT * INTR_PORTS_PER_ASIC
+                               && subpriv->dio.intr.asic < 0) {
+                               /* this is an interrupt subdevice, so setup the struct */
+                               subpriv->dio.intr.asic = asic;
+                               subpriv->dio.intr.active = 0;
+                               subpriv->dio.intr.stop_count = 0;
+                               subpriv->dio.intr.first_chan = byte_no * 8;
+                               subpriv->dio.intr.asic_chan = thisasic_chanct;
+                               subpriv->dio.intr.num_asic_chans =
+                                       s->n_chan -
+                                       subpriv->dio.intr.first_chan;
+                               s->cancel = pcmmio_cancel;
+                               s->do_cmd = pcmmio_cmd;
+                               s->do_cmdtest = pcmmio_cmdtest;
+                               s->len_chanlist =
+                                       subpriv->dio.intr.num_asic_chans;
+                       }
+                       thisasic_chanct += CHANS_PER_PORT;
+               }
+               spin_lock_init(&subpriv->dio.intr.spinlock);
+
+               chans_left -= s->n_chan;
+
+               if (!chans_left) {
+                       asic = 0;       /* reset the asic to our first asic, to do intr subdevs */
+                       port = 0;
+               }
+
+       }
+
+       init_asics(dev);        /* clear out all the registers, basically */
+
+       for (asic = 0; irq[0] && asic < MAX_ASICS; ++asic) {
+               if (irq[asic]
+                       && comedi_request_irq(irq[asic], interrupt_pcmmio,
+                               IRQF_SHARED, thisboard->name, dev)) {
+                       int i;
+                       /* unroll the allocated irqs.. */
+                       for (i = asic - 1; i >= 0; --i) {
+                               comedi_free_irq(irq[i], dev);
+                               devpriv->asics[i].irq = irq[i] = 0;
+                       }
+                       irq[asic] = 0;
+               }
+               devpriv->asics[asic].irq = irq[asic];
+       }
+
+       dev->irq = irq[0];      /* grr.. wish comedi dev struct supported multiple
+                                  irqs.. */
+
+       if (irq[0]) {
+               printk("irq: %u ", irq[0]);
+               if (irq[1] && thisboard->dio_num_asics == 2)
+                       printk("second ASIC irq: %u ", irq[1]);
+       } else {
+               printk("(IRQ mode disabled) ");
+       }
+
+       printk("attached\n");
+
+       return 1;
+}
+
+/*
+ * _detach is called to deconfigure a device.  It should deallocate
+ * resources.
+ * This function is also called when _attach() fails, so it should be
+ * careful not to release resources that were not necessarily
+ * allocated by _attach().  dev->private and dev->subdevices are
+ * deallocated automatically by the core.
+ */
+static int pcmmio_detach(struct comedi_device * dev)
+{
+       int i;
+
+       printk("comedi%d: %s: remove\n", dev->minor, driver.driver_name);
+       if (dev->iobase)
+               release_region(dev->iobase, thisboard->total_iosize);
+
+       for (i = 0; i < MAX_ASICS; ++i) {
+               if (devpriv && devpriv->asics[i].irq)
+                       comedi_free_irq(devpriv->asics[i].irq, dev);
+       }
+
+       if (devpriv && devpriv->sprivs)
+               kfree(devpriv->sprivs);
+
+       return 0;
+}
+
+/* DIO devices are slightly special.  Although it is possible to
+ * implement the insn_read/insn_write interface, it is much more
+ * useful to applications if you implement the insn_bits interface.
+ * This allows packed reading/writing of the DIO channels.  The
+ * comedi core can convert between insn_bits and insn_read/write */
+static int pcmmio_dio_insn_bits(struct comedi_device * dev, struct comedi_subdevice * s,
+       struct comedi_insn * insn, unsigned int * data)
+{
+       int byte_no;
+       if (insn->n != 2)
+               return -EINVAL;
+
+       /* NOTE:
+          reading a 0 means this channel was high
+          writine a 0 sets the channel high
+          reading a 1 means this channel was low
+          writing a 1 means set this channel low
+
+          Therefore everything is always inverted. */
+
+       /* The insn data is a mask in data[0] and the new data
+        * in data[1], each channel cooresponding to a bit. */
+
+#ifdef DAMMIT_ITS_BROKEN
+       /* DEBUG */
+       printk("write mask: %08x  data: %08x\n", data[0], data[1]);
+#endif
+
+       s->state = 0;
+
+       for (byte_no = 0; byte_no < s->n_chan / CHANS_PER_PORT; ++byte_no) {
+               /* address of 8-bit port */
+               unsigned long ioaddr = subpriv->iobases[byte_no],
+                       /* bit offset of port in 32-bit doubleword */
+                       offset = byte_no * 8;
+               /* this 8-bit port's data */
+               unsigned char byte = 0,
+                       /* The write mask for this port (if any) */
+                       write_mask_byte = (data[0] >> offset) & 0xff,
+                       /* The data byte for this port */
+                       data_byte = (data[1] >> offset) & 0xff;
+
+               byte = inb(ioaddr);     /* read all 8-bits for this port */
+
+#ifdef DAMMIT_ITS_BROKEN
+               /* DEBUG */
+               printk("byte %d wmb %02x db %02x offset %02d io %04x, data_in %02x ", byte_no, (unsigned)write_mask_byte, (unsigned)data_byte, offset, ioaddr, (unsigned)byte);
+#endif
+
+               if (write_mask_byte) {
+                       /* this byte has some write_bits -- so set the output lines */
+                       byte &= ~write_mask_byte;       /* clear bits for write mask */
+                       byte |= ~data_byte & write_mask_byte;   /* set to inverted data_byte */
+                       /* Write out the new digital output state */
+                       outb(byte, ioaddr);
+               }
+#ifdef DAMMIT_ITS_BROKEN
+               /* DEBUG */
+               printk("data_out_byte %02x\n", (unsigned)byte);
+#endif
+               /* save the digital input lines for this byte.. */
+               s->state |= ((unsigned int)byte) << offset;
+       }
+
+       /* now return the DIO lines to data[1] - note they came inverted! */
+       data[1] = ~s->state;
+
+#ifdef DAMMIT_ITS_BROKEN
+       /* DEBUG */
+       printk("s->state %08x data_out %08x\n", s->state, data[1]);
+#endif
+
+       return 2;
+}
+
+/* The input or output configuration of each digital line is
+ * configured by a special insn_config instruction.  chanspec
+ * contains the channel to be changed, and data[0] contains the
+ * value COMEDI_INPUT or COMEDI_OUTPUT. */
+static int pcmmio_dio_insn_config(struct comedi_device * dev, struct comedi_subdevice * s,
+       struct comedi_insn * insn, unsigned int * data)
+{
+       int chan = CR_CHAN(insn->chanspec), byte_no = chan / 8, bit_no =
+               chan % 8;
+       unsigned long ioaddr;
+       unsigned char byte;
+
+       /* Compute ioaddr for this channel */
+       ioaddr = subpriv->iobases[byte_no];
+
+       /* NOTE:
+          writing a 0 an IO channel's bit sets the channel to INPUT
+          and pulls the line high as well
+
+          writing a 1 to an IO channel's  bit pulls the line low
+
+          All channels are implicitly always in OUTPUT mode -- but when
+          they are high they can be considered to be in INPUT mode..
+
+          Thus, we only force channels low if the config request was INPUT,
+          otherwise we do nothing to the hardware.    */
+
+       switch (data[0]) {
+       case INSN_CONFIG_DIO_OUTPUT:
+               /* save to io_bits -- don't actually do anything since
+                  all input channels are also output channels... */
+               s->io_bits |= 1 << chan;
+               break;
+       case INSN_CONFIG_DIO_INPUT:
+               /* write a 0 to the actual register representing the channel
+                  to set it to 'input'.  0 means "float high". */
+               byte = inb(ioaddr);
+               byte &= ~(1 << bit_no);
+                               /**< set input channel to '0' */
+
+               /* write out byte -- this is the only time we actually affect the
+                  hardware as all channels are implicitly output -- but input
+                  channels are set to float-high */
+               outb(byte, ioaddr);
+
+               /* save to io_bits */
+               s->io_bits &= ~(1 << chan);
+               break;
+
+       case INSN_CONFIG_DIO_QUERY:
+               /* retreive from shadow register */
+               data[1] =
+                       (s->
+                       io_bits & (1 << chan)) ? COMEDI_OUTPUT : COMEDI_INPUT;
+               return insn->n;
+               break;
+
+       default:
+               return -EINVAL;
+               break;
+       }
+
+       return insn->n;
+}
+
+static void init_asics(struct comedi_device * dev)
+{                              /* sets up an
+                                  ASIC chip to defaults */
+       int asic;
+
+       for (asic = 0; asic < thisboard->dio_num_asics; ++asic) {
+               int port, page;
+               unsigned long baseaddr = devpriv->asics[asic].iobase;
+
+               switch_page(dev, asic, 0);      /* switch back to page 0 */
+
+               /* first, clear all the DIO port bits */
+               for (port = 0; port < PORTS_PER_ASIC; ++port)
+                       outb(0, baseaddr + REG_PORT0 + port);
+
+               /* Next, clear all the paged registers for each page */
+               for (page = 1; page < NUM_PAGES; ++page) {
+                       int reg;
+                       /* now clear all the paged registers */
+                       switch_page(dev, asic, page);
+                       for (reg = FIRST_PAGED_REG;
+                               reg < FIRST_PAGED_REG + NUM_PAGED_REGS; ++reg)
+                               outb(0, baseaddr + reg);
+               }
+
+               /* DEBUG  set rising edge interrupts on port0 of both asics */
+               /*switch_page(dev, asic, PAGE_POL);
+                  outb(0xff, baseaddr + REG_POL0);
+                  switch_page(dev, asic, PAGE_ENAB);
+                  outb(0xff, baseaddr + REG_ENAB0); */
+               /* END DEBUG */
+
+               switch_page(dev, asic, 0);      /* switch back to default page 0 */
+
+       }
+}
+
+static void switch_page(struct comedi_device * dev, int asic, int page)
+{
+       if (asic < 0 || asic >= thisboard->dio_num_asics)
+               return;         /* paranoia */
+       if (page < 0 || page >= NUM_PAGES)
+               return;         /* more paranoia */
+
+       devpriv->asics[asic].pagelock &= ~REG_PAGE_MASK;
+       devpriv->asics[asic].pagelock |= page << REG_PAGE_BITOFFSET;
+
+       /* now write out the shadow register */
+       outb(devpriv->asics[asic].pagelock,
+               devpriv->asics[asic].iobase + REG_PAGELOCK);
+}
+
+#ifdef notused
+static void lock_port(struct comedi_device * dev, int asic, int port)
+{
+       if (asic < 0 || asic >= thisboard->dio_num_asics)
+               return;         /* paranoia */
+       if (port < 0 || port >= PORTS_PER_ASIC)
+               return;         /* more paranoia */
+
+       devpriv->asics[asic].pagelock |= 0x1 << port;
+       /* now write out the shadow register */
+       outb(devpriv->asics[asic].pagelock,
+               devpriv->asics[asic].iobase + REG_PAGELOCK);
+       return;
+}
+
+static void unlock_port(struct comedi_device * dev, int asic, int port)
+{
+       if (asic < 0 || asic >= thisboard->dio_num_asics)
+               return;         /* paranoia */
+       if (port < 0 || port >= PORTS_PER_ASIC)
+               return;         /* more paranoia */
+       devpriv->asics[asic].pagelock &= ~(0x1 << port) | REG_LOCK_MASK;
+       /* now write out the shadow register */
+       outb(devpriv->asics[asic].pagelock,
+               devpriv->asics[asic].iobase + REG_PAGELOCK);
+}
+#endif /* notused */
+
+static irqreturn_t interrupt_pcmmio(int irq, void *d PT_REGS_ARG)
+{
+       int asic, got1 = 0;
+       struct comedi_device *dev = (struct comedi_device *) d;
+
+       for (asic = 0; asic < MAX_ASICS; ++asic) {
+               if (irq == devpriv->asics[asic].irq) {
+                       unsigned long flags;
+                       unsigned triggered = 0;
+                       unsigned long iobase = devpriv->asics[asic].iobase;
+                       /* it is an interrupt for ASIC #asic */
+                       unsigned char int_pend;
+
+                       comedi_spin_lock_irqsave(&devpriv->asics[asic].spinlock,
+                               flags);
+
+                       int_pend = inb(iobase + REG_INT_PENDING) & 0x07;
+
+                       if (int_pend) {
+                               int port;
+                               for (port = 0; port < INTR_PORTS_PER_ASIC;
+                                       ++port) {
+                                       if (int_pend & (0x1 << port)) {
+                                               unsigned char
+                                                       io_lines_with_edges = 0;
+                                               switch_page(dev, asic,
+                                                       PAGE_INT_ID);
+                                               io_lines_with_edges =
+                                                       inb(iobase +
+                                                       REG_INT_ID0 + port);
+
+                                               if (io_lines_with_edges)
+                                                       /* clear pending interrupt */
+                                                       outb(0, iobase +
+                                                               REG_INT_ID0 +
+                                                               port);
+
+                                               triggered |=
+                                                       io_lines_with_edges <<
+                                                       port * 8;
+                                       }
+                               }
+
+                               ++got1;
+                       }
+
+                       comedi_spin_unlock_irqrestore(&devpriv->asics[asic].
+                               spinlock, flags);
+
+                       if (triggered) {
+                               struct comedi_subdevice *s;
+                               /* TODO here: dispatch io lines to subdevs with commands.. */
+                               printk("PCMMIO DEBUG: got edge detect interrupt %d asic %d which_chans: %06x\n", irq, asic, triggered);
+                               for (s = dev->subdevices + 2;
+                                       s < dev->subdevices + dev->n_subdevices;
+                                       ++s) {
+                                       if (subpriv->dio.intr.asic == asic) {   /* this is an interrupt subdev, and it matches this asic! */
+                                               unsigned long flags;
+                                               unsigned oldevents;
+
+                                               comedi_spin_lock_irqsave
+                                                       (&subpriv->dio.intr.
+                                                       spinlock, flags);
+
+                                               oldevents = s->async->events;
+
+                                               if (subpriv->dio.intr.active) {
+                                                       unsigned mytrig =
+                                                               ((triggered >>
+                                                                       subpriv->
+                                                                       dio.
+                                                                       intr.
+                                                                       asic_chan)
+                                                               & ((0x1 << subpriv->dio.intr.num_asic_chans) - 1)) << subpriv->dio.intr.first_chan;
+                                                       if (mytrig & subpriv->
+                                                               dio.intr.
+                                                               enabled_mask) {
+                                                               unsigned int val =
+                                                                       0;
+                                                               unsigned int n,
+                                                                       ch, len;
+
+                                                               len = s->async->
+                                                                       cmd.
+                                                                       chanlist_len;
+                                                               for (n = 0;
+                                                                       n < len;
+                                                                       n++) {
+                                                                       ch = CR_CHAN(s->async->cmd.chanlist[n]);
+                                                                       if (mytrig & (1U << ch)) {
+                                                                               val |= (1U << n);
+                                                                       }
+                                                               }
+                                                               /* Write the scan to the buffer. */
+                                                               if (comedi_buf_put(s->async, ((short *) & val)[0])
+                                                                       &&
+                                                                       comedi_buf_put
+                                                                       (s->async, ((short *) & val)[1])) {
+                                                                       s->async->events |= (COMEDI_CB_BLOCK | COMEDI_CB_EOS);
+                                                               } else {
+                                                                       /* Overflow! Stop acquisition!! */
+                                                                       /* TODO: STOP_ACQUISITION_CALL_HERE!! */
+                                                                       pcmmio_stop_intr
+                                                                               (dev,
+                                                                               s);
+                                                               }
+
+                                                               /* Check for end of acquisition. */
+                                                               if (!subpriv->
+                                                                       dio.
+                                                                       intr.
+                                                                       continuous)
+                                                               {
+                                                                       /* stop_src == TRIG_COUNT */
+                                                                       if (subpriv->dio.intr.stop_count > 0) {
+                                                                               subpriv->
+                                                                                       dio.
+                                                                                       intr.
+                                                                                       stop_count--;
+                                                                               if (subpriv->dio.intr.stop_count == 0) {
+                                                                                       s->async->events |= COMEDI_CB_EOA;
+                                                                                       /* TODO: STOP_ACQUISITION_CALL_HERE!! */
+                                                                                       pcmmio_stop_intr
+                                                                                               (dev,
+                                                                                               s);
+                                                                               }
+                                                                       }
+                                                               }
+                                                       }
+                                               }
+
+                                               comedi_spin_unlock_irqrestore
+                                                       (&subpriv->dio.intr.
+                                                       spinlock, flags);
+
+                                               if (oldevents !=
+                                                       s->async->events) {
+                                                       comedi_event(dev, s);
+                                               }
+
+                                       }
+
+                               }
+                       }
+
+               }
+       }
+       if (!got1)
+               return IRQ_NONE;        /* interrupt from other source */
+       return IRQ_HANDLED;
+}
+
+static void pcmmio_stop_intr(struct comedi_device * dev, struct comedi_subdevice * s)
+{
+       int nports, firstport, asic, port;
+
+       if ((asic = subpriv->dio.intr.asic) < 0)
+               return;         /* not an interrupt subdev */
+
+       subpriv->dio.intr.enabled_mask = 0;
+       subpriv->dio.intr.active = 0;
+       s->async->inttrig = 0;
+       nports = subpriv->dio.intr.num_asic_chans / CHANS_PER_PORT;
+       firstport = subpriv->dio.intr.asic_chan / CHANS_PER_PORT;
+       switch_page(dev, asic, PAGE_ENAB);
+       for (port = firstport; port < firstport + nports; ++port) {
+               /* disable all intrs for this subdev.. */
+               outb(0, devpriv->asics[asic].iobase + REG_ENAB0 + port);
+       }
+}
+
+static int pcmmio_start_intr(struct comedi_device * dev, struct comedi_subdevice * s)
+{
+       if (!subpriv->dio.intr.continuous && subpriv->dio.intr.stop_count == 0) {
+               /* An empty acquisition! */
+               s->async->events |= COMEDI_CB_EOA;
+               subpriv->dio.intr.active = 0;
+               return 1;
+       } else {
+               unsigned bits = 0, pol_bits = 0, n;
+               int nports, firstport, asic, port;
+               struct comedi_cmd *cmd = &s->async->cmd;
+
+               if ((asic = subpriv->dio.intr.asic) < 0)
+                       return 1;       /* not an interrupt
+                                          subdev */
+               subpriv->dio.intr.enabled_mask = 0;
+               subpriv->dio.intr.active = 1;
+               nports = subpriv->dio.intr.num_asic_chans / CHANS_PER_PORT;
+               firstport = subpriv->dio.intr.asic_chan / CHANS_PER_PORT;
+               if (cmd->chanlist) {
+                       for (n = 0; n < cmd->chanlist_len; n++) {
+                               bits |= (1U << CR_CHAN(cmd->chanlist[n]));
+                               pol_bits |= (CR_AREF(cmd->chanlist[n])
+                                       || CR_RANGE(cmd->chanlist[n]) ? 1U : 0U)
+                                       << CR_CHAN(cmd->chanlist[n]);
+                       }
+               }
+               bits &= ((0x1 << subpriv->dio.intr.num_asic_chans) -
+                       1) << subpriv->dio.intr.first_chan;
+               subpriv->dio.intr.enabled_mask = bits;
+
+               {               /* the below code configures the board to use a specific IRQ from 0-15. */
+                       unsigned char b;
+                       /* set resource enable register to enable IRQ operation */
+                       outb(1 << 4, dev->iobase + 3);
+                       /* set bits 0-3 of b to the irq number from 0-15 */
+                       b = dev->irq & ((1 << 4) - 1);
+                       outb(b, dev->iobase + 2);
+                       /* done, we told the board what irq to use */
+               }
+
+               switch_page(dev, asic, PAGE_ENAB);
+               for (port = firstport; port < firstport + nports; ++port) {
+                       unsigned enab =
+                               bits >> (subpriv->dio.intr.first_chan + (port -
+                                       firstport) * 8) & 0xff, pol =
+                               pol_bits >> (subpriv->dio.intr.first_chan +
+                               (port - firstport) * 8) & 0xff;
+                       /* set enab intrs for this subdev.. */
+                       outb(enab,
+                               devpriv->asics[asic].iobase + REG_ENAB0 + port);
+                       switch_page(dev, asic, PAGE_POL);
+                       outb(pol,
+                               devpriv->asics[asic].iobase + REG_ENAB0 + port);
+               }
+       }
+       return 0;
+}
+
+static int pcmmio_cancel(struct comedi_device * dev, struct comedi_subdevice * s)
+{
+       unsigned long flags;
+
+       comedi_spin_lock_irqsave(&subpriv->dio.intr.spinlock, flags);
+       if (subpriv->dio.intr.active)
+               pcmmio_stop_intr(dev, s);
+       comedi_spin_unlock_irqrestore(&subpriv->dio.intr.spinlock, flags);
+
+       return 0;
+}
+
+/*
+ * Internal trigger function to start acquisition for an 'INTERRUPT' subdevice.
+ */
+static int
+pcmmio_inttrig_start_intr(struct comedi_device * dev, struct comedi_subdevice * s,
+       unsigned int trignum)
+{
+       unsigned long flags;
+       int event = 0;
+
+       if (trignum != 0)
+               return -EINVAL;
+
+       comedi_spin_lock_irqsave(&subpriv->dio.intr.spinlock, flags);
+       s->async->inttrig = 0;
+       if (subpriv->dio.intr.active) {
+               event = pcmmio_start_intr(dev, s);
+       }
+       comedi_spin_unlock_irqrestore(&subpriv->dio.intr.spinlock, flags);
+
+       if (event) {
+               comedi_event(dev, s);
+       }
+
+       return 1;
+}
+
+/*
+ * 'do_cmd' function for an 'INTERRUPT' subdevice.
+ */
+static int pcmmio_cmd(struct comedi_device * dev, struct comedi_subdevice * s)
+{
+       struct comedi_cmd *cmd = &s->async->cmd;
+       unsigned long flags;
+       int event = 0;
+
+       comedi_spin_lock_irqsave(&subpriv->dio.intr.spinlock, flags);
+       subpriv->dio.intr.active = 1;
+
+       /* Set up end of acquisition. */
+       switch (cmd->stop_src) {
+       case TRIG_COUNT:
+               subpriv->dio.intr.continuous = 0;
+               subpriv->dio.intr.stop_count = cmd->stop_arg;
+               break;
+       default:
+               /* TRIG_NONE */
+               subpriv->dio.intr.continuous = 1;
+               subpriv->dio.intr.stop_count = 0;
+               break;
+       }
+
+       /* Set up start of acquisition. */
+       switch (cmd->start_src) {
+       case TRIG_INT:
+               s->async->inttrig = pcmmio_inttrig_start_intr;
+               break;
+       default:
+               /* TRIG_NOW */
+               event = pcmmio_start_intr(dev, s);
+               break;
+       }
+       comedi_spin_unlock_irqrestore(&subpriv->dio.intr.spinlock, flags);
+
+       if (event) {
+               comedi_event(dev, s);
+       }
+
+       return 0;
+}
+
+/*
+ * 'do_cmdtest' function for an 'INTERRUPT' subdevice.
+ */
+static int
+pcmmio_cmdtest(struct comedi_device * dev, struct comedi_subdevice * s, struct comedi_cmd * cmd)
+{
+       int err = 0;
+       unsigned int tmp;
+
+       /* step 1: make sure trigger sources are trivially valid */
+
+       tmp = cmd->start_src;
+       cmd->start_src &= (TRIG_NOW | TRIG_INT);
+       if (!cmd->start_src || tmp != cmd->start_src)
+               err++;
+
+       tmp = cmd->scan_begin_src;
+       cmd->scan_begin_src &= TRIG_EXT;
+       if (!cmd->scan_begin_src || tmp != cmd->scan_begin_src)
+               err++;
+
+       tmp = cmd->convert_src;
+       cmd->convert_src &= TRIG_NOW;
+       if (!cmd->convert_src || tmp != cmd->convert_src)
+               err++;
+
+       tmp = cmd->scan_end_src;
+       cmd->scan_end_src &= TRIG_COUNT;
+       if (!cmd->scan_end_src || tmp != cmd->scan_end_src)
+               err++;
+
+       tmp = cmd->stop_src;
+       cmd->stop_src &= (TRIG_COUNT | TRIG_NONE);
+       if (!cmd->stop_src || tmp != cmd->stop_src)
+               err++;
+
+       if (err)
+               return 1;
+
+       /* step 2: make sure trigger sources are unique and mutually compatible */
+
+       /* these tests are true if more than one _src bit is set */
+       if ((cmd->start_src & (cmd->start_src - 1)) != 0)
+               err++;
+       if ((cmd->scan_begin_src & (cmd->scan_begin_src - 1)) != 0)
+               err++;
+       if ((cmd->convert_src & (cmd->convert_src - 1)) != 0)
+               err++;
+       if ((cmd->scan_end_src & (cmd->scan_end_src - 1)) != 0)
+               err++;
+       if ((cmd->stop_src & (cmd->stop_src - 1)) != 0)
+               err++;
+
+       if (err)
+               return 2;
+
+       /* step 3: make sure arguments are trivially compatible */
+
+       /* cmd->start_src == TRIG_NOW || cmd->start_src == TRIG_INT */
+       if (cmd->start_arg != 0) {
+               cmd->start_arg = 0;
+               err++;
+       }
+
+       /* cmd->scan_begin_src == TRIG_EXT */
+       if (cmd->scan_begin_arg != 0) {
+               cmd->scan_begin_arg = 0;
+               err++;
+       }
+
+       /* cmd->convert_src == TRIG_NOW */
+       if (cmd->convert_arg != 0) {
+               cmd->convert_arg = 0;
+               err++;
+       }
+
+       /* cmd->scan_end_src == TRIG_COUNT */
+       if (cmd->scan_end_arg != cmd->chanlist_len) {
+               cmd->scan_end_arg = cmd->chanlist_len;
+               err++;
+       }
+
+       switch (cmd->stop_src) {
+       case TRIG_COUNT:
+               /* any count allowed */
+               break;
+       case TRIG_NONE:
+               if (cmd->stop_arg != 0) {
+                       cmd->stop_arg = 0;
+                       err++;
+               }
+               break;
+       default:
+               break;
+       }
+
+       if (err)
+               return 3;
+
+       /* step 4: fix up any arguments */
+
+       /* if (err) return 4; */
+
+       return 0;
+}
+
+static int adc_wait_ready(unsigned long iobase)
+{
+       unsigned long retry = 100000;
+       while (retry--)
+               if (inb(iobase + 3) & 0x80)
+                       return 0;
+       return 1;
+}
+
+/* All this is for AI and AO */
+static int ai_rinsn(struct comedi_device * dev, struct comedi_subdevice * s,
+       struct comedi_insn * insn, unsigned int * data)
+{
+       int n;
+       unsigned long iobase = subpriv->iobase;
+
+       /*
+          1. write the CMD byte (to BASE+2)
+          2. read junk lo byte (BASE+0)
+          3. read junk hi byte (BASE+1)
+          4. (mux settled so) write CMD byte again (BASE+2)
+          5. read valid lo byte(BASE+0)
+          6. read valid hi byte(BASE+1)
+
+          Additionally note that the BASE += 4 if the channel >= 8
+        */
+
+       /* convert n samples */
+       for (n = 0; n < insn->n; n++) {
+               unsigned chan = CR_CHAN(insn->chanspec), range =
+                       CR_RANGE(insn->chanspec), aref =
+                       CR_AREF(insn->chanspec);
+               unsigned char command_byte = 0;
+               unsigned iooffset = 0;
+               short sample, adc_adjust = 0;
+
+               if (chan > 7)
+                       chan -= 8, iooffset = 4;        /* use the second dword for channels > 7 */
+
+               if (aref != AREF_DIFF) {
+                       aref = AREF_GROUND;
+                       command_byte |= 1 << 7; /* set bit 7 to indicate single-ended */
+               }
+               if (range < 2)
+                       adc_adjust = 0x8000;    /* bipolar ranges (-5,5 .. -10,10 need to be adjusted -- that is.. they need to wrap around by adding 0x8000 */
+
+               if (chan % 2) {
+                       command_byte |= 1 << 6; /* odd-numbered channels have bit 6 set */
+               }
+
+               /* select the channel, bits 4-5 == chan/2 */
+               command_byte |= ((chan / 2) & 0x3) << 4;
+
+               /* set the range, bits 2-3 */
+               command_byte |= (range & 0x3) << 2;
+
+               /* need to do this twice to make sure mux settled */
+               outb(command_byte, iobase + iooffset + 2);      /* chan/range/aref select */
+
+               adc_wait_ready(iobase + iooffset);      /* wait for the adc to say it finised the conversion */
+
+               outb(command_byte, iobase + iooffset + 2);      /* select the chan/range/aref AGAIN */
+
+               adc_wait_ready(iobase + iooffset);
+
+               sample = inb(iobase + iooffset + 0);    /* read data lo byte */
+               sample |= inb(iobase + iooffset + 1) << 8;      /* read data hi byte */
+               sample += adc_adjust;   /* adjustment .. munge data */
+               data[n] = sample;
+       }
+       /* return the number of samples read/written */
+       return n;
+}
+
+static int ao_rinsn(struct comedi_device * dev, struct comedi_subdevice * s,
+       struct comedi_insn * insn, unsigned int * data)
+{
+       int n;
+       for (n = 0; n < insn->n; n++) {
+               unsigned chan = CR_CHAN(insn->chanspec);
+               if (chan < s->n_chan)
+                       data[n] = subpriv->ao.shadow_samples[chan];
+       }
+       return n;
+}
+
+static int wait_dac_ready(unsigned long iobase)
+{
+       unsigned long retry = 100000L;
+
+       /* This may seem like an absurd way to handle waiting and violates the
+          "no busy waiting" policy. The fact is that the hardware is
+          normally so fast that we usually only need one time through the loop
+          anyway. The longer timeout is for rare occasions and for detecting
+          non-existant hardware.  */
+
+       while (retry--) {
+               if (inb(iobase + 3) & 0x80)
+                       return 0;
+
+       }
+       return 1;
+}
+
+static int ao_winsn(struct comedi_device * dev, struct comedi_subdevice * s,
+       struct comedi_insn * insn, unsigned int * data)
+{
+       int n;
+       unsigned iobase = subpriv->iobase, iooffset = 0;
+
+       for (n = 0; n < insn->n; n++) {
+               unsigned chan = CR_CHAN(insn->chanspec), range =
+                       CR_RANGE(insn->chanspec);
+               if (chan < s->n_chan) {
+                       unsigned char command_byte = 0, range_byte =
+                               range & ((1 << 4) - 1);
+                       if (chan >= 4)
+                               chan -= 4, iooffset += 4;
+                       /* set the range.. */
+                       outb(range_byte, iobase + iooffset + 0);
+                       outb(0, iobase + iooffset + 1);
+
+                       /* tell it to begin */
+                       command_byte = (chan << 1) | 0x60;
+                       outb(command_byte, iobase + iooffset + 2);
+
+                       wait_dac_ready(iobase + iooffset);
+
+                       outb(data[n] & 0xff, iobase + iooffset + 0);    /* low order byte */
+                       outb((data[n] >> 8) & 0xff, iobase + iooffset + 1);     /* high order byte */
+                       command_byte = 0x70 | (chan << 1);      /* set bit 4 of command byte to indicate data is loaded and trigger conversion */
+                       /* trigger converion */
+                       outb(command_byte, iobase + iooffset + 2);
+
+                       wait_dac_ready(iobase + iooffset);
+
+                       subpriv->ao.shadow_samples[chan] = data[n];     /* save to shadow register for ao_rinsn */
+               }
+       }
+       return n;
+}
+
+/*
+ * A convenient macro that defines init_module() and cleanup_module(),
+ * as necessary.
+ */
+COMEDI_INITCLEANUP(driver);