staging: comedi: ni_labpc: split common code to ni_labpc_common
authorIan Abbott <abbotti@mev.co.uk>
Tue, 19 Aug 2014 15:06:33 +0000 (16:06 +0100)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Sat, 30 Aug 2014 20:18:56 +0000 (13:18 -0700)
The "ni_labpc" module is a Comedi driver for the National Instruments
Lab-PC series of ISA data acquistion boards, and also provides common
code for the "ni_labpc_pci" and "ni_labpci_cs" modules (for PCI boards
and PCMCIA cards).

Split out the common code into a new module "ni_labpc_common", leaving
the driver for the ISA boards in the existing "ni_labpc" module.  This
removes the C preprocessor conditional directives from the resulting
".c" files (although they remain in the included header file
"ni_labpc_isadma.h").

Unneccessary `#include` directives have been removed from the resulting
".c" files.

Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/staging/comedi/drivers/Makefile
drivers/staging/comedi/drivers/ni_labpc.c
drivers/staging/comedi/drivers/ni_labpc_common.c [new file with mode: 0644]

index 87ac79136084ea56718753e9bc9e0e9e0b6723cf..12b20bb6b53a8a20090a87a79e99ab730aa5d8c1 100644 (file)
@@ -50,6 +50,7 @@ obj-$(CONFIG_COMEDI_NI_AT_A2150)      += ni_at_a2150.o
 obj-$(CONFIG_COMEDI_NI_AT_AO)          += ni_at_ao.o
 obj-$(CONFIG_COMEDI_NI_ATMIO)          += ni_atmio.o
 obj-$(CONFIG_COMEDI_NI_ATMIO16D)       += ni_atmio16d.o
+obj-$(CONFIG_COMEDI_NI_LABPC_ISA)      += ni_labpc.o
 obj-$(CONFIG_COMEDI_PCMAD)             += pcmad.o
 obj-$(CONFIG_COMEDI_PCMDA12)           += pcmda12.o
 obj-$(CONFIG_COMEDI_PCMMIO)            += pcmmio.o
@@ -135,7 +136,7 @@ obj-$(CONFIG_COMEDI_VMK80XX)                += vmk80xx.o
 obj-$(CONFIG_COMEDI_MITE)              += mite.o
 obj-$(CONFIG_COMEDI_NI_TIO)            += ni_tio.o
 obj-$(CONFIG_COMEDI_NI_TIOCMD)         += ni_tiocmd.o
-obj-$(CONFIG_COMEDI_NI_LABPC)          += ni_labpc.o
+obj-$(CONFIG_COMEDI_NI_LABPC)          += ni_labpc_common.o
 obj-$(CONFIG_COMEDI_NI_LABPC_ISADMA)   += ni_labpc_isadma.o
 
 obj-$(CONFIG_COMEDI_8255)              += 8255.o
index ccf5ce800697c942d9133b94df4e4782d40c56e0..1fbfdb4c80c072331d9a2473f82d8697013544d5 100644 (file)
  */
 
 #include <linux/module.h>
-#include <linux/interrupt.h>
-#include <linux/slab.h>
-#include <linux/io.h>
-#include <linux/delay.h>
 
 #include "../comedidev.h"
 
-#include "8253.h"
-#include "8255.h"
-#include "comedi_fc.h"
 #include "ni_labpc.h"
-#include "ni_labpc_regs.h"
 #include "ni_labpc_isadma.h"
 
-enum scan_mode {
-       MODE_SINGLE_CHAN,
-       MODE_SINGLE_CHAN_INTERVAL,
-       MODE_MULT_CHAN_UP,
-       MODE_MULT_CHAN_DOWN,
-};
-
-static const struct comedi_lrange range_labpc_plus_ai = {
-       16, {
-               BIP_RANGE(5),
-               BIP_RANGE(4),
-               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(8),
-               UNI_RANGE(5),
-               UNI_RANGE(2),
-               UNI_RANGE(1),
-               UNI_RANGE(0.5),
-               UNI_RANGE(0.2),
-               UNI_RANGE(0.1)
-       }
-};
-
-static const struct comedi_lrange range_labpc_1200_ai = {
-       14, {
-               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 struct comedi_lrange range_labpc_ao = {
-       2, {
-               BIP_RANGE(5),
-               UNI_RANGE(10)
-       }
-};
-
-/* functions that do inb/outb and readb/writeb so we can use
- * function pointers to decide which to use */
-static unsigned int labpc_inb(struct comedi_device *dev, unsigned long reg)
-{
-       return inb(dev->iobase + reg);
-}
-
-static void labpc_outb(struct comedi_device *dev,
-                      unsigned int byte, unsigned long reg)
-{
-       outb(byte, dev->iobase + reg);
-}
-
-static unsigned int labpc_readb(struct comedi_device *dev, unsigned long reg)
-{
-       return readb(dev->mmio + reg);
-}
-
-static void labpc_writeb(struct comedi_device *dev,
-                        unsigned int byte, unsigned long reg)
-{
-       writeb(byte, dev->mmio + reg);
-}
-
-#if IS_ENABLED(CONFIG_COMEDI_NI_LABPC_ISA)
 static const struct labpc_boardinfo labpc_boards[] = {
        {
                .name                   = "lab-pc-1200",
@@ -169,1272 +82,7 @@ static const struct labpc_boardinfo labpc_boards[] = {
                .has_ao                 = 1,
        },
 };
-#endif
-
-static void labpc_counter_load(struct comedi_device *dev,
-                              unsigned long reg,
-                              unsigned int counter_number,
-                              unsigned int count,
-                              unsigned int mode)
-{
-       if (dev->mmio) {
-               i8254_mm_set_mode(dev->mmio + reg, 0, counter_number, mode);
-               i8254_mm_write(dev->mmio + reg, 0, counter_number, count);
-       } else {
-               i8254_set_mode(dev->iobase + reg, 0, counter_number, mode);
-               i8254_write(dev->iobase + reg, 0, counter_number, count);
-       }
-}
-
-static void labpc_counter_set_mode(struct comedi_device *dev,
-                                  unsigned long reg,
-                                  unsigned int counter_number,
-                                  unsigned int mode)
-{
-       if (dev->mmio)
-               i8254_mm_set_mode(dev->mmio + reg, 0, counter_number, mode);
-       else
-               i8254_set_mode(dev->iobase + reg, 0, counter_number, mode);
-}
-
-static int labpc_cancel(struct comedi_device *dev, struct comedi_subdevice *s)
-{
-       struct labpc_private *devpriv = dev->private;
-       unsigned long flags;
-
-       spin_lock_irqsave(&dev->spinlock, flags);
-       devpriv->cmd2 &= ~(CMD2_SWTRIG | CMD2_HWTRIG | CMD2_PRETRIG);
-       devpriv->write_byte(dev, devpriv->cmd2, CMD2_REG);
-       spin_unlock_irqrestore(&dev->spinlock, flags);
-
-       devpriv->cmd3 = 0;
-       devpriv->write_byte(dev, devpriv->cmd3, CMD3_REG);
-
-       return 0;
-}
-
-static void labpc_ai_set_chan_and_gain(struct comedi_device *dev,
-                                      enum scan_mode mode,
-                                      unsigned int chan,
-                                      unsigned int range,
-                                      unsigned int aref)
-{
-       const struct labpc_boardinfo *board = comedi_board(dev);
-       struct labpc_private *devpriv = dev->private;
-
-       if (board->is_labpc1200) {
-               /*
-                * The LabPC-1200 boards do not have a gain
-                * of '0x10'. Skip the range values that would
-                * result in this gain.
-                */
-               range += (range > 0) + (range > 7);
-       }
-
-       /* munge channel bits for differential/scan disabled mode */
-       if ((mode == MODE_SINGLE_CHAN || mode == MODE_SINGLE_CHAN_INTERVAL) &&
-           aref == AREF_DIFF)
-               chan *= 2;
-       devpriv->cmd1 = CMD1_MA(chan);
-       devpriv->cmd1 |= CMD1_GAIN(range);
-
-       devpriv->write_byte(dev, devpriv->cmd1, CMD1_REG);
-}
-
-static void labpc_setup_cmd6_reg(struct comedi_device *dev,
-                                struct comedi_subdevice *s,
-                                enum scan_mode mode,
-                                enum transfer_type xfer,
-                                unsigned int range,
-                                unsigned int aref,
-                                bool ena_intr)
-{
-       const struct labpc_boardinfo *board = comedi_board(dev);
-       struct labpc_private *devpriv = dev->private;
-
-       if (!board->is_labpc1200)
-               return;
-
-       /* reference inputs to ground or common? */
-       if (aref != AREF_GROUND)
-               devpriv->cmd6 |= CMD6_NRSE;
-       else
-               devpriv->cmd6 &= ~CMD6_NRSE;
-
-       /* bipolar or unipolar range? */
-       if (comedi_range_is_unipolar(s, range))
-               devpriv->cmd6 |= CMD6_ADCUNI;
-       else
-               devpriv->cmd6 &= ~CMD6_ADCUNI;
-
-       /*  interrupt on fifo half full? */
-       if (xfer == fifo_half_full_transfer)
-               devpriv->cmd6 |= CMD6_HFINTEN;
-       else
-               devpriv->cmd6 &= ~CMD6_HFINTEN;
-
-       /* enable interrupt on counter a1 terminal count? */
-       if (ena_intr)
-               devpriv->cmd6 |= CMD6_DQINTEN;
-       else
-               devpriv->cmd6 &= ~CMD6_DQINTEN;
-
-       /* are we scanning up or down through channels? */
-       if (mode == MODE_MULT_CHAN_UP)
-               devpriv->cmd6 |= CMD6_SCANUP;
-       else
-               devpriv->cmd6 &= ~CMD6_SCANUP;
-
-       devpriv->write_byte(dev, devpriv->cmd6, CMD6_REG);
-}
-
-static unsigned int labpc_read_adc_fifo(struct comedi_device *dev)
-{
-       struct labpc_private *devpriv = dev->private;
-       unsigned int lsb = devpriv->read_byte(dev, ADC_FIFO_REG);
-       unsigned int msb = devpriv->read_byte(dev, ADC_FIFO_REG);
-
-       return (msb << 8) | lsb;
-}
-
-static void labpc_clear_adc_fifo(struct comedi_device *dev)
-{
-       struct labpc_private *devpriv = dev->private;
-
-       devpriv->write_byte(dev, 0x1, ADC_FIFO_CLEAR_REG);
-       labpc_read_adc_fifo(dev);
-}
-
-static int labpc_ai_eoc(struct comedi_device *dev,
-                       struct comedi_subdevice *s,
-                       struct comedi_insn *insn,
-                       unsigned long context)
-{
-       struct labpc_private *devpriv = dev->private;
-
-       devpriv->stat1 = devpriv->read_byte(dev, STAT1_REG);
-       if (devpriv->stat1 & STAT1_DAVAIL)
-               return 0;
-       return -EBUSY;
-}
-
-static int labpc_ai_insn_read(struct comedi_device *dev,
-                             struct comedi_subdevice *s,
-                             struct comedi_insn *insn,
-                             unsigned int *data)
-{
-       struct labpc_private *devpriv = dev->private;
-       unsigned int chan = CR_CHAN(insn->chanspec);
-       unsigned int range = CR_RANGE(insn->chanspec);
-       unsigned int aref = CR_AREF(insn->chanspec);
-       int ret;
-       int i;
-
-       /* disable timed conversions, interrupt generation and dma */
-       labpc_cancel(dev, s);
-
-       labpc_ai_set_chan_and_gain(dev, MODE_SINGLE_CHAN, chan, range, aref);
-
-       labpc_setup_cmd6_reg(dev, s, MODE_SINGLE_CHAN, fifo_not_empty_transfer,
-                            range, aref, false);
-
-       /* setup cmd4 register */
-       devpriv->cmd4 = 0;
-       devpriv->cmd4 |= CMD4_ECLKRCV;
-       /* single-ended/differential */
-       if (aref == AREF_DIFF)
-               devpriv->cmd4 |= CMD4_SEDIFF;
-       devpriv->write_byte(dev, devpriv->cmd4, CMD4_REG);
-
-       /* initialize pacer counter to prevent any problems */
-       labpc_counter_set_mode(dev, COUNTER_A_BASE_REG, 0, I8254_MODE2);
-
-       labpc_clear_adc_fifo(dev);
-
-       for (i = 0; i < insn->n; i++) {
-               /* trigger conversion */
-               devpriv->write_byte(dev, 0x1, ADC_START_CONVERT_REG);
-
-               ret = comedi_timeout(dev, s, insn, labpc_ai_eoc, 0);
-               if (ret)
-                       return ret;
-
-               data[i] = labpc_read_adc_fifo(dev);
-       }
-
-       return insn->n;
-}
-
-static bool labpc_use_continuous_mode(const struct comedi_cmd *cmd,
-                                     enum scan_mode mode)
-{
-       if (mode == MODE_SINGLE_CHAN || cmd->scan_begin_src == TRIG_FOLLOW)
-               return true;
-
-       return false;
-}
-
-static unsigned int labpc_ai_convert_period(const struct comedi_cmd *cmd,
-                                           enum scan_mode mode)
-{
-       if (cmd->convert_src != TRIG_TIMER)
-               return 0;
-
-       if (mode == MODE_SINGLE_CHAN && cmd->scan_begin_src == TRIG_TIMER)
-               return cmd->scan_begin_arg;
-
-       return cmd->convert_arg;
-}
-
-static void labpc_set_ai_convert_period(struct comedi_cmd *cmd,
-                                       enum scan_mode mode, unsigned int ns)
-{
-       if (cmd->convert_src != TRIG_TIMER)
-               return;
-
-       if (mode == MODE_SINGLE_CHAN &&
-           cmd->scan_begin_src == TRIG_TIMER) {
-               cmd->scan_begin_arg = ns;
-               if (cmd->convert_arg > cmd->scan_begin_arg)
-                       cmd->convert_arg = cmd->scan_begin_arg;
-       } else {
-               cmd->convert_arg = ns;
-       }
-}
-
-static unsigned int labpc_ai_scan_period(const struct comedi_cmd *cmd,
-                                        enum scan_mode mode)
-{
-       if (cmd->scan_begin_src != TRIG_TIMER)
-               return 0;
-
-       if (mode == MODE_SINGLE_CHAN && cmd->convert_src == TRIG_TIMER)
-               return 0;
-
-       return cmd->scan_begin_arg;
-}
-
-static void labpc_set_ai_scan_period(struct comedi_cmd *cmd,
-                                    enum scan_mode mode, unsigned int ns)
-{
-       if (cmd->scan_begin_src != TRIG_TIMER)
-               return;
-
-       if (mode == MODE_SINGLE_CHAN && cmd->convert_src == TRIG_TIMER)
-               return;
-
-       cmd->scan_begin_arg = ns;
-}
-
-/* figures out what counter values to use based on command */
-static void labpc_adc_timing(struct comedi_device *dev, struct comedi_cmd *cmd,
-                            enum scan_mode mode)
-{
-       struct labpc_private *devpriv = dev->private;
-       /* max value for 16 bit counter in mode 2 */
-       const int max_counter_value = 0x10000;
-       /* min value for 16 bit counter in mode 2 */
-       const int min_counter_value = 2;
-       unsigned int base_period;
-       unsigned int scan_period;
-       unsigned int convert_period;
-
-       /*
-        * if both convert and scan triggers are TRIG_TIMER, then they
-        * both rely on counter b0
-        */
-       convert_period = labpc_ai_convert_period(cmd, mode);
-       scan_period = labpc_ai_scan_period(cmd, mode);
-       if (convert_period && scan_period) {
-               /*
-                * pick the lowest b0 divisor value we can (for maximum input
-                * clock speed on convert and scan counters)
-                */
-               devpriv->divisor_b0 = (scan_period - 1) /
-                   (I8254_OSC_BASE_2MHZ * max_counter_value) + 1;
-               if (devpriv->divisor_b0 < min_counter_value)
-                       devpriv->divisor_b0 = min_counter_value;
-               if (devpriv->divisor_b0 > max_counter_value)
-                       devpriv->divisor_b0 = max_counter_value;
-
-               base_period = I8254_OSC_BASE_2MHZ * devpriv->divisor_b0;
-
-               /*  set a0 for conversion frequency and b1 for scan frequency */
-               switch (cmd->flags & TRIG_ROUND_MASK) {
-               default:
-               case TRIG_ROUND_NEAREST:
-                       devpriv->divisor_a0 =
-                           (convert_period + (base_period / 2)) / base_period;
-                       devpriv->divisor_b1 =
-                           (scan_period + (base_period / 2)) / base_period;
-                       break;
-               case TRIG_ROUND_UP:
-                       devpriv->divisor_a0 =
-                           (convert_period + (base_period - 1)) / base_period;
-                       devpriv->divisor_b1 =
-                           (scan_period + (base_period - 1)) / base_period;
-                       break;
-               case TRIG_ROUND_DOWN:
-                       devpriv->divisor_a0 = convert_period / base_period;
-                       devpriv->divisor_b1 = scan_period / base_period;
-                       break;
-               }
-               /*  make sure a0 and b1 values are acceptable */
-               if (devpriv->divisor_a0 < min_counter_value)
-                       devpriv->divisor_a0 = min_counter_value;
-               if (devpriv->divisor_a0 > max_counter_value)
-                       devpriv->divisor_a0 = max_counter_value;
-               if (devpriv->divisor_b1 < min_counter_value)
-                       devpriv->divisor_b1 = min_counter_value;
-               if (devpriv->divisor_b1 > max_counter_value)
-                       devpriv->divisor_b1 = max_counter_value;
-               /*  write corrected timings to command */
-               labpc_set_ai_convert_period(cmd, mode,
-                                           base_period * devpriv->divisor_a0);
-               labpc_set_ai_scan_period(cmd, mode,
-                                        base_period * devpriv->divisor_b1);
-               /*
-                * if only one TRIG_TIMER is used, we can employ the generic
-                * cascaded timing functions
-                */
-       } else if (scan_period) {
-               /*
-                * calculate cascaded counter values
-                * that give desired scan timing
-                */
-               i8253_cascade_ns_to_timer(I8254_OSC_BASE_2MHZ,
-                                         &devpriv->divisor_b1,
-                                         &devpriv->divisor_b0,
-                                         &scan_period, cmd->flags);
-               labpc_set_ai_scan_period(cmd, mode, scan_period);
-       } else if (convert_period) {
-               /*
-                * calculate cascaded counter values
-                * that give desired conversion timing
-                */
-               i8253_cascade_ns_to_timer(I8254_OSC_BASE_2MHZ,
-                                         &devpriv->divisor_a0,
-                                         &devpriv->divisor_b0,
-                                         &convert_period, cmd->flags);
-               labpc_set_ai_convert_period(cmd, mode, convert_period);
-       }
-}
-
-static enum scan_mode labpc_ai_scan_mode(const struct comedi_cmd *cmd)
-{
-       unsigned int chan0;
-       unsigned int chan1;
-
-       if (cmd->chanlist_len == 1)
-               return MODE_SINGLE_CHAN;
-
-       /* chanlist may be NULL during cmdtest */
-       if (cmd->chanlist == NULL)
-               return MODE_MULT_CHAN_UP;
-
-       chan0 = CR_CHAN(cmd->chanlist[0]);
-       chan1 = CR_CHAN(cmd->chanlist[1]);
-
-       if (chan0 < chan1)
-               return MODE_MULT_CHAN_UP;
-
-       if (chan0 > chan1)
-               return MODE_MULT_CHAN_DOWN;
-
-       return MODE_SINGLE_CHAN_INTERVAL;
-}
-
-static int labpc_ai_check_chanlist(struct comedi_device *dev,
-                                  struct comedi_subdevice *s,
-                                  struct comedi_cmd *cmd)
-{
-       enum scan_mode mode = labpc_ai_scan_mode(cmd);
-       unsigned int chan0 = CR_CHAN(cmd->chanlist[0]);
-       unsigned int range0 = CR_RANGE(cmd->chanlist[0]);
-       unsigned int aref0 = CR_AREF(cmd->chanlist[0]);
-       int i;
-
-       if (mode == MODE_SINGLE_CHAN)
-               return 0;
-
-       for (i = 0; i < cmd->chanlist_len; i++) {
-               unsigned int chan = CR_CHAN(cmd->chanlist[i]);
-               unsigned int range = CR_RANGE(cmd->chanlist[i]);
-               unsigned int aref = CR_AREF(cmd->chanlist[i]);
-
-               switch (mode) {
-               case MODE_SINGLE_CHAN:
-                       break;
-               case MODE_SINGLE_CHAN_INTERVAL:
-                       if (chan != chan0) {
-                               dev_dbg(dev->class_dev,
-                                       "channel scanning order specified in chanlist is not supported by hardware\n");
-                               return -EINVAL;
-                       }
-                       break;
-               case MODE_MULT_CHAN_UP:
-                       if (chan != i) {
-                               dev_dbg(dev->class_dev,
-                                       "channel scanning order specified in chanlist is not supported by hardware\n");
-                               return -EINVAL;
-                       }
-                       break;
-               case MODE_MULT_CHAN_DOWN:
-                       if (chan != (cmd->chanlist_len - i - 1)) {
-                               dev_dbg(dev->class_dev,
-                                       "channel scanning order specified in chanlist is not supported by hardware\n");
-                               return -EINVAL;
-                       }
-                       break;
-               }
-
-               if (range != range0) {
-                       dev_dbg(dev->class_dev,
-                               "entries in chanlist must all have the same range\n");
-                       return -EINVAL;
-               }
-
-               if (aref != aref0) {
-                       dev_dbg(dev->class_dev,
-                               "entries in chanlist must all have the same reference\n");
-                       return -EINVAL;
-               }
-       }
-
-       return 0;
-}
-
-static int labpc_ai_cmdtest(struct comedi_device *dev,
-                           struct comedi_subdevice *s, struct comedi_cmd *cmd)
-{
-       const struct labpc_boardinfo *board = comedi_board(dev);
-       int err = 0;
-       int tmp, tmp2;
-       unsigned int stop_mask;
-       enum scan_mode mode;
-
-       /* Step 1 : check if triggers are trivially valid */
-
-       err |= cfc_check_trigger_src(&cmd->start_src, TRIG_NOW | TRIG_EXT);
-       err |= cfc_check_trigger_src(&cmd->scan_begin_src,
-                                       TRIG_TIMER | TRIG_FOLLOW | TRIG_EXT);
-       err |= cfc_check_trigger_src(&cmd->convert_src, TRIG_TIMER | TRIG_EXT);
-       err |= cfc_check_trigger_src(&cmd->scan_end_src, TRIG_COUNT);
-
-       stop_mask = TRIG_COUNT | TRIG_NONE;
-       if (board->is_labpc1200)
-               stop_mask |= TRIG_EXT;
-       err |= cfc_check_trigger_src(&cmd->stop_src, stop_mask);
-
-       if (err)
-               return 1;
-
-       /* Step 2a : make sure trigger sources are unique */
-
-       err |= cfc_check_trigger_is_unique(cmd->start_src);
-       err |= cfc_check_trigger_is_unique(cmd->scan_begin_src);
-       err |= cfc_check_trigger_is_unique(cmd->convert_src);
-       err |= cfc_check_trigger_is_unique(cmd->stop_src);
-
-       /* Step 2b : and mutually compatible */
-
-       /* can't have external stop and start triggers at once */
-       if (cmd->start_src == TRIG_EXT && cmd->stop_src == TRIG_EXT)
-               err++;
-
-       if (err)
-               return 2;
-
-       /* Step 3: check if arguments are trivially valid */
-
-       switch (cmd->start_src) {
-       case TRIG_NOW:
-               err |= cfc_check_trigger_arg_is(&cmd->start_arg, 0);
-               break;
-       case TRIG_EXT:
-               /* start_arg value is ignored */
-               break;
-       }
-
-       if (!cmd->chanlist_len)
-               err |= -EINVAL;
-       err |= cfc_check_trigger_arg_is(&cmd->scan_end_arg, cmd->chanlist_len);
-
-       if (cmd->convert_src == TRIG_TIMER)
-               err |= cfc_check_trigger_arg_min(&cmd->convert_arg,
-                                                board->ai_speed);
-
-       /* make sure scan timing is not too fast */
-       if (cmd->scan_begin_src == TRIG_TIMER) {
-               if (cmd->convert_src == TRIG_TIMER)
-                       err |= cfc_check_trigger_arg_min(&cmd->scan_begin_arg,
-                                       cmd->convert_arg * cmd->chanlist_len);
-               err |= cfc_check_trigger_arg_min(&cmd->scan_begin_arg,
-                               board->ai_speed * cmd->chanlist_len);
-       }
-
-       switch (cmd->stop_src) {
-       case TRIG_COUNT:
-               err |= cfc_check_trigger_arg_min(&cmd->stop_arg, 1);
-               break;
-       case TRIG_NONE:
-               err |= cfc_check_trigger_arg_is(&cmd->stop_arg, 0);
-               break;
-               /*
-                * TRIG_EXT doesn't care since it doesn't
-                * trigger off a numbered channel
-                */
-       default:
-               break;
-       }
-
-       if (err)
-               return 3;
-
-       /* step 4: fix up any arguments */
-
-       tmp = cmd->convert_arg;
-       tmp2 = cmd->scan_begin_arg;
-       mode = labpc_ai_scan_mode(cmd);
-       labpc_adc_timing(dev, cmd, mode);
-       if (tmp != cmd->convert_arg || tmp2 != 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 |= labpc_ai_check_chanlist(dev, s, cmd);
-
-       if (err)
-               return 5;
-
-       return 0;
-}
-
-static int labpc_ai_cmd(struct comedi_device *dev, struct comedi_subdevice *s)
-{
-       const struct labpc_boardinfo *board = comedi_board(dev);
-       struct labpc_private *devpriv = dev->private;
-       struct comedi_async *async = s->async;
-       struct comedi_cmd *cmd = &async->cmd;
-       enum scan_mode mode = labpc_ai_scan_mode(cmd);
-       unsigned int chanspec = (mode == MODE_MULT_CHAN_UP) ?
-                               cmd->chanlist[cmd->chanlist_len - 1] :
-                               cmd->chanlist[0];
-       unsigned int chan = CR_CHAN(chanspec);
-       unsigned int range = CR_RANGE(chanspec);
-       unsigned int aref = CR_AREF(chanspec);
-       enum transfer_type xfer;
-       unsigned long flags;
-
-       /* make sure board is disabled before setting up acquisition */
-       labpc_cancel(dev, s);
-
-       /*  initialize software conversion count */
-       if (cmd->stop_src == TRIG_COUNT)
-               devpriv->count = cmd->stop_arg * cmd->chanlist_len;
-
-       /*  setup hardware conversion counter */
-       if (cmd->stop_src == TRIG_EXT) {
-               /*
-                * load counter a1 with count of 3
-                * (pc+ manual says this is minimum allowed) using mode 0
-                */
-               labpc_counter_load(dev, COUNTER_A_BASE_REG,
-                                  1, 3, I8254_MODE0);
-       } else  {
-               /* just put counter a1 in mode 0 to set its output low */
-               labpc_counter_set_mode(dev, COUNTER_A_BASE_REG, 1, I8254_MODE0);
-       }
 
-       /* figure out what method we will use to transfer data */
-       if (labpc_have_dma_chan(dev) &&
-           /* dma unsafe at RT priority,
-            * and too much setup time for TRIG_WAKE_EOS */
-           (cmd->flags & (TRIG_WAKE_EOS | TRIG_RT)) == 0)
-               xfer = isa_dma_transfer;
-       else if (/* pc-plus has no fifo-half full interrupt */
-                board->is_labpc1200 &&
-                /* wake-end-of-scan should interrupt on fifo not empty */
-                (cmd->flags & TRIG_WAKE_EOS) == 0 &&
-                /* make sure we are taking more than just a few points */
-                (cmd->stop_src != TRIG_COUNT || devpriv->count > 256))
-               xfer = fifo_half_full_transfer;
-       else
-               xfer = fifo_not_empty_transfer;
-       devpriv->current_transfer = xfer;
-
-       labpc_ai_set_chan_and_gain(dev, mode, chan, range, aref);
-
-       labpc_setup_cmd6_reg(dev, s, mode, xfer, range, aref,
-                            (cmd->stop_src == TRIG_EXT));
-
-       /* manual says to set scan enable bit on second pass */
-       if (mode == MODE_MULT_CHAN_UP || mode == MODE_MULT_CHAN_DOWN) {
-               devpriv->cmd1 |= CMD1_SCANEN;
-               /* need a brief delay before enabling scan, or scan
-                * list will get screwed when you switch
-                * between scan up to scan down mode - dunno why */
-               udelay(1);
-               devpriv->write_byte(dev, devpriv->cmd1, CMD1_REG);
-       }
-
-       devpriv->write_byte(dev, cmd->chanlist_len, INTERVAL_COUNT_REG);
-       /*  load count */
-       devpriv->write_byte(dev, 0x1, INTERVAL_STROBE_REG);
-
-       if (cmd->convert_src == TRIG_TIMER ||
-           cmd->scan_begin_src == TRIG_TIMER) {
-               /*  set up pacing */
-               labpc_adc_timing(dev, cmd, mode);
-               /*  load counter b0 in mode 3 */
-               labpc_counter_load(dev, COUNTER_B_BASE_REG,
-                                  0, devpriv->divisor_b0, I8254_MODE3);
-       }
-       /*  set up conversion pacing */
-       if (labpc_ai_convert_period(cmd, mode)) {
-               /*  load counter a0 in mode 2 */
-               labpc_counter_load(dev, COUNTER_A_BASE_REG,
-                                  0, devpriv->divisor_a0, I8254_MODE2);
-       } else {
-               /* initialize pacer counter to prevent any problems */
-               labpc_counter_set_mode(dev, COUNTER_A_BASE_REG, 0, I8254_MODE2);
-       }
-
-       /*  set up scan pacing */
-       if (labpc_ai_scan_period(cmd, mode)) {
-               /*  load counter b1 in mode 2 */
-               labpc_counter_load(dev, COUNTER_B_BASE_REG,
-                                  1, devpriv->divisor_b1, I8254_MODE2);
-       }
-
-       labpc_clear_adc_fifo(dev);
-
-       if (xfer == isa_dma_transfer)
-               labpc_setup_dma(dev, s);
-
-       /*  enable error interrupts */
-       devpriv->cmd3 |= CMD3_ERRINTEN;
-       /*  enable fifo not empty interrupt? */
-       if (xfer == fifo_not_empty_transfer)
-               devpriv->cmd3 |= CMD3_FIFOINTEN;
-       devpriv->write_byte(dev, devpriv->cmd3, CMD3_REG);
-
-       /*  setup any external triggering/pacing (cmd4 register) */
-       devpriv->cmd4 = 0;
-       if (cmd->convert_src != TRIG_EXT)
-               devpriv->cmd4 |= CMD4_ECLKRCV;
-       /* XXX should discard first scan when using interval scanning
-        * since manual says it is not synced with scan clock */
-       if (!labpc_use_continuous_mode(cmd, mode)) {
-               devpriv->cmd4 |= CMD4_INTSCAN;
-               if (cmd->scan_begin_src == TRIG_EXT)
-                       devpriv->cmd4 |= CMD4_EOIRCV;
-       }
-       /*  single-ended/differential */
-       if (aref == AREF_DIFF)
-               devpriv->cmd4 |= CMD4_SEDIFF;
-       devpriv->write_byte(dev, devpriv->cmd4, CMD4_REG);
-
-       /*  startup acquisition */
-
-       spin_lock_irqsave(&dev->spinlock, flags);
-
-       /* use 2 cascaded counters for pacing */
-       devpriv->cmd2 |= CMD2_TBSEL;
-
-       devpriv->cmd2 &= ~(CMD2_SWTRIG | CMD2_HWTRIG | CMD2_PRETRIG);
-       if (cmd->start_src == TRIG_EXT)
-               devpriv->cmd2 |= CMD2_HWTRIG;
-       else
-               devpriv->cmd2 |= CMD2_SWTRIG;
-       if (cmd->stop_src == TRIG_EXT)
-               devpriv->cmd2 |= (CMD2_HWTRIG | CMD2_PRETRIG);
-
-       devpriv->write_byte(dev, devpriv->cmd2, CMD2_REG);
-
-       spin_unlock_irqrestore(&dev->spinlock, flags);
-
-       return 0;
-}
-
-/* read all available samples from ai fifo */
-static int labpc_drain_fifo(struct comedi_device *dev)
-{
-       struct labpc_private *devpriv = dev->private;
-       struct comedi_async *async = dev->read_subdev->async;
-       struct comedi_cmd *cmd = &async->cmd;
-       unsigned short data;
-       const int timeout = 10000;
-       unsigned int i;
-
-       devpriv->stat1 = devpriv->read_byte(dev, STAT1_REG);
-
-       for (i = 0; (devpriv->stat1 & STAT1_DAVAIL) && i < timeout;
-            i++) {
-               /*  quit if we have all the data we want */
-               if (cmd->stop_src == TRIG_COUNT) {
-                       if (devpriv->count == 0)
-                               break;
-                       devpriv->count--;
-               }
-               data = labpc_read_adc_fifo(dev);
-               cfc_write_to_buffer(dev->read_subdev, data);
-               devpriv->stat1 = devpriv->read_byte(dev, STAT1_REG);
-       }
-       if (i == timeout) {
-               dev_err(dev->class_dev, "ai timeout, fifo never empties\n");
-               async->events |= COMEDI_CB_ERROR | COMEDI_CB_EOA;
-               return -1;
-       }
-
-       return 0;
-}
-
-/* makes sure all data acquired by board is transferred to comedi (used
- * when acquisition is terminated by stop_src == TRIG_EXT). */
-static void labpc_drain_dregs(struct comedi_device *dev)
-{
-       struct labpc_private *devpriv = dev->private;
-
-       if (devpriv->current_transfer == isa_dma_transfer)
-               labpc_drain_dma(dev);
-
-       labpc_drain_fifo(dev);
-}
-
-/* interrupt service routine */
-static irqreturn_t labpc_interrupt(int irq, void *d)
-{
-       struct comedi_device *dev = d;
-       const struct labpc_boardinfo *board = comedi_board(dev);
-       struct labpc_private *devpriv = dev->private;
-       struct comedi_subdevice *s = dev->read_subdev;
-       struct comedi_async *async;
-       struct comedi_cmd *cmd;
-
-       if (!dev->attached) {
-               dev_err(dev->class_dev, "premature interrupt\n");
-               return IRQ_HANDLED;
-       }
-
-       async = s->async;
-       cmd = &async->cmd;
-
-       /* read board status */
-       devpriv->stat1 = devpriv->read_byte(dev, STAT1_REG);
-       if (board->is_labpc1200)
-               devpriv->stat2 = devpriv->read_byte(dev, STAT2_REG);
-
-       if ((devpriv->stat1 & (STAT1_GATA0 | STAT1_CNTINT | STAT1_OVERFLOW |
-                              STAT1_OVERRUN | STAT1_DAVAIL)) == 0 &&
-           (devpriv->stat2 & STAT2_OUTA1) == 0 &&
-           (devpriv->stat2 & STAT2_FIFONHF)) {
-               return IRQ_NONE;
-       }
-
-       if (devpriv->stat1 & STAT1_OVERRUN) {
-               /* clear error interrupt */
-               devpriv->write_byte(dev, 0x1, ADC_FIFO_CLEAR_REG);
-               async->events |= COMEDI_CB_ERROR | COMEDI_CB_EOA;
-               cfc_handle_events(dev, s);
-               dev_err(dev->class_dev, "overrun\n");
-               return IRQ_HANDLED;
-       }
-
-       if (devpriv->current_transfer == isa_dma_transfer)
-               labpc_handle_dma_status(dev);
-       else
-               labpc_drain_fifo(dev);
-
-       if (devpriv->stat1 & STAT1_CNTINT) {
-               dev_err(dev->class_dev, "handled timer interrupt?\n");
-               /*  clear it */
-               devpriv->write_byte(dev, 0x1, TIMER_CLEAR_REG);
-       }
-
-       if (devpriv->stat1 & STAT1_OVERFLOW) {
-               /*  clear error interrupt */
-               devpriv->write_byte(dev, 0x1, ADC_FIFO_CLEAR_REG);
-               async->events |= COMEDI_CB_ERROR | COMEDI_CB_EOA;
-               cfc_handle_events(dev, s);
-               dev_err(dev->class_dev, "overflow\n");
-               return IRQ_HANDLED;
-       }
-       /*  handle external stop trigger */
-       if (cmd->stop_src == TRIG_EXT) {
-               if (devpriv->stat2 & STAT2_OUTA1) {
-                       labpc_drain_dregs(dev);
-                       async->events |= COMEDI_CB_EOA;
-               }
-       }
-
-       /* TRIG_COUNT end of acquisition */
-       if (cmd->stop_src == TRIG_COUNT) {
-               if (devpriv->count == 0)
-                       async->events |= COMEDI_CB_EOA;
-       }
-
-       cfc_handle_events(dev, s);
-       return IRQ_HANDLED;
-}
-
-static int labpc_ao_insn_write(struct comedi_device *dev,
-                              struct comedi_subdevice *s,
-                              struct comedi_insn *insn,
-                              unsigned int *data)
-{
-       const struct labpc_boardinfo *board = comedi_board(dev);
-       struct labpc_private *devpriv = dev->private;
-       int channel, range;
-       unsigned long flags;
-       int lsb, msb;
-
-       channel = CR_CHAN(insn->chanspec);
-
-       /* turn off pacing of analog output channel */
-       /* note: hardware bug in daqcard-1200 means pacing cannot
-        * be independently enabled/disabled for its the two channels */
-       spin_lock_irqsave(&dev->spinlock, flags);
-       devpriv->cmd2 &= ~CMD2_LDAC(channel);
-       devpriv->write_byte(dev, devpriv->cmd2, CMD2_REG);
-       spin_unlock_irqrestore(&dev->spinlock, flags);
-
-       /* set range */
-       if (board->is_labpc1200) {
-               range = CR_RANGE(insn->chanspec);
-               if (comedi_range_is_unipolar(s, range))
-                       devpriv->cmd6 |= CMD6_DACUNI(channel);
-               else
-                       devpriv->cmd6 &= ~CMD6_DACUNI(channel);
-               /*  write to register */
-               devpriv->write_byte(dev, devpriv->cmd6, CMD6_REG);
-       }
-       /* send data */
-       lsb = data[0] & 0xff;
-       msb = (data[0] >> 8) & 0xff;
-       devpriv->write_byte(dev, lsb, DAC_LSB_REG(channel));
-       devpriv->write_byte(dev, msb, DAC_MSB_REG(channel));
-
-       /* remember value for readback */
-       devpriv->ao_value[channel] = data[0];
-
-       return 1;
-}
-
-static int labpc_ao_insn_read(struct comedi_device *dev,
-                             struct comedi_subdevice *s,
-                             struct comedi_insn *insn,
-                             unsigned int *data)
-{
-       struct labpc_private *devpriv = dev->private;
-
-       data[0] = devpriv->ao_value[CR_CHAN(insn->chanspec)];
-
-       return 1;
-}
-
-/* lowlevel write to eeprom/dac */
-static void labpc_serial_out(struct comedi_device *dev, unsigned int value,
-                            unsigned int value_width)
-{
-       struct labpc_private *devpriv = dev->private;
-       int i;
-
-       for (i = 1; i <= value_width; i++) {
-               /*  clear serial clock */
-               devpriv->cmd5 &= ~CMD5_SCLK;
-               /*  send bits most significant bit first */
-               if (value & (1 << (value_width - i)))
-                       devpriv->cmd5 |= CMD5_SDATA;
-               else
-                       devpriv->cmd5 &= ~CMD5_SDATA;
-               udelay(1);
-               devpriv->write_byte(dev, devpriv->cmd5, CMD5_REG);
-               /*  set clock to load bit */
-               devpriv->cmd5 |= CMD5_SCLK;
-               udelay(1);
-               devpriv->write_byte(dev, devpriv->cmd5, CMD5_REG);
-       }
-}
-
-/* lowlevel read from eeprom */
-static unsigned int labpc_serial_in(struct comedi_device *dev)
-{
-       struct labpc_private *devpriv = dev->private;
-       unsigned int value = 0;
-       int i;
-       const int value_width = 8;      /*  number of bits wide values are */
-
-       for (i = 1; i <= value_width; i++) {
-               /*  set serial clock */
-               devpriv->cmd5 |= CMD5_SCLK;
-               udelay(1);
-               devpriv->write_byte(dev, devpriv->cmd5, CMD5_REG);
-               /*  clear clock bit */
-               devpriv->cmd5 &= ~CMD5_SCLK;
-               udelay(1);
-               devpriv->write_byte(dev, devpriv->cmd5, CMD5_REG);
-               /*  read bits most significant bit first */
-               udelay(1);
-               devpriv->stat2 = devpriv->read_byte(dev, STAT2_REG);
-               if (devpriv->stat2 & STAT2_PROMOUT)
-                       value |= 1 << (value_width - i);
-       }
-
-       return value;
-}
-
-static unsigned int labpc_eeprom_read(struct comedi_device *dev,
-                                     unsigned int address)
-{
-       struct labpc_private *devpriv = dev->private;
-       unsigned int value;
-       /*  bits to tell eeprom to expect a read */
-       const int read_instruction = 0x3;
-       /*  8 bit write lengths to eeprom */
-       const int write_length = 8;
-
-       /*  enable read/write to eeprom */
-       devpriv->cmd5 &= ~CMD5_EEPROMCS;
-       udelay(1);
-       devpriv->write_byte(dev, devpriv->cmd5, CMD5_REG);
-       devpriv->cmd5 |= (CMD5_EEPROMCS | CMD5_WRTPRT);
-       udelay(1);
-       devpriv->write_byte(dev, devpriv->cmd5, CMD5_REG);
-
-       /*  send read instruction */
-       labpc_serial_out(dev, read_instruction, write_length);
-       /*  send 8 bit address to read from */
-       labpc_serial_out(dev, address, write_length);
-       /*  read result */
-       value = labpc_serial_in(dev);
-
-       /*  disable read/write to eeprom */
-       devpriv->cmd5 &= ~(CMD5_EEPROMCS | CMD5_WRTPRT);
-       udelay(1);
-       devpriv->write_byte(dev, devpriv->cmd5, CMD5_REG);
-
-       return value;
-}
-
-static unsigned int labpc_eeprom_read_status(struct comedi_device *dev)
-{
-       struct labpc_private *devpriv = dev->private;
-       unsigned int value;
-       const int read_status_instruction = 0x5;
-       const int write_length = 8;     /*  8 bit write lengths to eeprom */
-
-       /*  enable read/write to eeprom */
-       devpriv->cmd5 &= ~CMD5_EEPROMCS;
-       udelay(1);
-       devpriv->write_byte(dev, devpriv->cmd5, CMD5_REG);
-       devpriv->cmd5 |= (CMD5_EEPROMCS | CMD5_WRTPRT);
-       udelay(1);
-       devpriv->write_byte(dev, devpriv->cmd5, CMD5_REG);
-
-       /*  send read status instruction */
-       labpc_serial_out(dev, read_status_instruction, write_length);
-       /*  read result */
-       value = labpc_serial_in(dev);
-
-       /*  disable read/write to eeprom */
-       devpriv->cmd5 &= ~(CMD5_EEPROMCS | CMD5_WRTPRT);
-       udelay(1);
-       devpriv->write_byte(dev, devpriv->cmd5, CMD5_REG);
-
-       return value;
-}
-
-static int labpc_eeprom_write(struct comedi_device *dev,
-                             unsigned int address, unsigned int value)
-{
-       struct labpc_private *devpriv = dev->private;
-       const int write_enable_instruction = 0x6;
-       const int write_instruction = 0x2;
-       const int write_length = 8;     /*  8 bit write lengths to eeprom */
-       const int write_in_progress_bit = 0x1;
-       const int timeout = 10000;
-       int i;
-
-       /*  make sure there isn't already a write in progress */
-       for (i = 0; i < timeout; i++) {
-               if ((labpc_eeprom_read_status(dev) & write_in_progress_bit) ==
-                   0)
-                       break;
-       }
-       if (i == timeout) {
-               dev_err(dev->class_dev, "eeprom write timed out\n");
-               return -ETIME;
-       }
-       /*  update software copy of eeprom */
-       devpriv->eeprom_data[address] = value;
-
-       /*  enable read/write to eeprom */
-       devpriv->cmd5 &= ~CMD5_EEPROMCS;
-       udelay(1);
-       devpriv->write_byte(dev, devpriv->cmd5, CMD5_REG);
-       devpriv->cmd5 |= (CMD5_EEPROMCS | CMD5_WRTPRT);
-       udelay(1);
-       devpriv->write_byte(dev, devpriv->cmd5, CMD5_REG);
-
-       /*  send write_enable instruction */
-       labpc_serial_out(dev, write_enable_instruction, write_length);
-       devpriv->cmd5 &= ~CMD5_EEPROMCS;
-       udelay(1);
-       devpriv->write_byte(dev, devpriv->cmd5, CMD5_REG);
-
-       /*  send write instruction */
-       devpriv->cmd5 |= CMD5_EEPROMCS;
-       udelay(1);
-       devpriv->write_byte(dev, devpriv->cmd5, CMD5_REG);
-       labpc_serial_out(dev, write_instruction, write_length);
-       /*  send 8 bit address to write to */
-       labpc_serial_out(dev, address, write_length);
-       /*  write value */
-       labpc_serial_out(dev, value, write_length);
-       devpriv->cmd5 &= ~CMD5_EEPROMCS;
-       udelay(1);
-       devpriv->write_byte(dev, devpriv->cmd5, CMD5_REG);
-
-       /*  disable read/write to eeprom */
-       devpriv->cmd5 &= ~(CMD5_EEPROMCS | CMD5_WRTPRT);
-       udelay(1);
-       devpriv->write_byte(dev, devpriv->cmd5, CMD5_REG);
-
-       return 0;
-}
-
-/* writes to 8 bit calibration dacs */
-static void write_caldac(struct comedi_device *dev, unsigned int channel,
-                        unsigned int value)
-{
-       struct labpc_private *devpriv = dev->private;
-
-       if (value == devpriv->caldac[channel])
-               return;
-       devpriv->caldac[channel] = value;
-
-       /*  clear caldac load bit and make sure we don't write to eeprom */
-       devpriv->cmd5 &= ~(CMD5_CALDACLD | CMD5_EEPROMCS | CMD5_WRTPRT);
-       udelay(1);
-       devpriv->write_byte(dev, devpriv->cmd5, CMD5_REG);
-
-       /*  write 4 bit channel */
-       labpc_serial_out(dev, channel, 4);
-       /*  write 8 bit caldac value */
-       labpc_serial_out(dev, value, 8);
-
-       /*  set and clear caldac bit to load caldac value */
-       devpriv->cmd5 |= CMD5_CALDACLD;
-       udelay(1);
-       devpriv->write_byte(dev, devpriv->cmd5, CMD5_REG);
-       devpriv->cmd5 &= ~CMD5_CALDACLD;
-       udelay(1);
-       devpriv->write_byte(dev, devpriv->cmd5, CMD5_REG);
-}
-
-static int labpc_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);
-
-       /*
-        * Only write the last data value to the caldac. Preceding
-        * data would be overwritten anyway.
-        */
-       if (insn->n > 0)
-               write_caldac(dev, chan, data[insn->n - 1]);
-
-       return insn->n;
-}
-
-static int labpc_calib_insn_read(struct comedi_device *dev,
-                                struct comedi_subdevice *s,
-                                struct comedi_insn *insn,
-                                unsigned int *data)
-{
-       struct labpc_private *devpriv = dev->private;
-       unsigned int chan = CR_CHAN(insn->chanspec);
-       int i;
-
-       for (i = 0; i < insn->n; i++)
-               data[i] = devpriv->caldac[chan];
-
-       return insn->n;
-}
-
-static int labpc_eeprom_insn_write(struct comedi_device *dev,
-                                  struct comedi_subdevice *s,
-                                  struct comedi_insn *insn,
-                                  unsigned int *data)
-{
-       unsigned int chan = CR_CHAN(insn->chanspec);
-       int ret;
-
-       /* only allow writes to user area of eeprom */
-       if (chan < 16 || chan > 127)
-               return -EINVAL;
-
-       /*
-        * Only write the last data value to the eeprom. Preceding
-        * data would be overwritten anyway.
-        */
-       if (insn->n > 0) {
-               ret = labpc_eeprom_write(dev, chan, data[insn->n - 1]);
-               if (ret)
-                       return ret;
-       }
-
-       return insn->n;
-}
-
-static int labpc_eeprom_insn_read(struct comedi_device *dev,
-                                 struct comedi_subdevice *s,
-                                 struct comedi_insn *insn,
-                                 unsigned int *data)
-{
-       struct labpc_private *devpriv = dev->private;
-       unsigned int chan = CR_CHAN(insn->chanspec);
-       int i;
-
-       for (i = 0; i < insn->n; i++)
-               data[i] = devpriv->eeprom_data[chan];
-
-       return insn->n;
-}
-
-int labpc_common_attach(struct comedi_device *dev,
-                       unsigned int irq, unsigned long isr_flags)
-{
-       const struct labpc_boardinfo *board = comedi_board(dev);
-       struct labpc_private *devpriv = dev->private;
-       struct comedi_subdevice *s;
-       int ret;
-       int i;
-
-       if (dev->mmio) {
-               devpriv->read_byte = labpc_readb;
-               devpriv->write_byte = labpc_writeb;
-       } else {
-               devpriv->read_byte = labpc_inb;
-               devpriv->write_byte = labpc_outb;
-       }
-
-       /* initialize board's command registers */
-       devpriv->write_byte(dev, devpriv->cmd1, CMD1_REG);
-       devpriv->write_byte(dev, devpriv->cmd2, CMD2_REG);
-       devpriv->write_byte(dev, devpriv->cmd3, CMD3_REG);
-       devpriv->write_byte(dev, devpriv->cmd4, CMD4_REG);
-       if (board->is_labpc1200) {
-               devpriv->write_byte(dev, devpriv->cmd5, CMD5_REG);
-               devpriv->write_byte(dev, devpriv->cmd6, CMD6_REG);
-       }
-
-       if (irq) {
-               ret = request_irq(irq, labpc_interrupt, isr_flags,
-                                 dev->board_name, dev);
-               if (ret == 0)
-                       dev->irq = irq;
-       }
-
-       ret = comedi_alloc_subdevices(dev, 5);
-       if (ret)
-               return ret;
-
-       /* analog input subdevice */
-       s = &dev->subdevices[0];
-       s->type         = COMEDI_SUBD_AI;
-       s->subdev_flags = SDF_READABLE | SDF_GROUND | SDF_COMMON | SDF_DIFF;
-       s->n_chan       = 8;
-       s->len_chanlist = 8;
-       s->maxdata      = 0x0fff;
-       s->range_table  = board->is_labpc1200 ?
-                         &range_labpc_1200_ai : &range_labpc_plus_ai;
-       s->insn_read    = labpc_ai_insn_read;
-       if (dev->irq) {
-               dev->read_subdev = s;
-               s->subdev_flags |= SDF_CMD_READ;
-               s->do_cmd       = labpc_ai_cmd;
-               s->do_cmdtest   = labpc_ai_cmdtest;
-               s->cancel       = labpc_cancel;
-       }
-
-       /* analog output */
-       s = &dev->subdevices[1];
-       if (board->has_ao) {
-               s->type         = COMEDI_SUBD_AO;
-               s->subdev_flags = SDF_READABLE | SDF_WRITABLE | SDF_GROUND;
-               s->n_chan       = NUM_AO_CHAN;
-               s->maxdata      = 0x0fff;
-               s->range_table  = &range_labpc_ao;
-               s->insn_read    = labpc_ao_insn_read;
-               s->insn_write   = labpc_ao_insn_write;
-
-               /* initialize analog outputs to a known value */
-               for (i = 0; i < s->n_chan; i++) {
-                       short lsb, msb;
-
-                       devpriv->ao_value[i] = s->maxdata / 2;
-                       lsb = devpriv->ao_value[i] & 0xff;
-                       msb = (devpriv->ao_value[i] >> 8) & 0xff;
-                       devpriv->write_byte(dev, lsb, DAC_LSB_REG(i));
-                       devpriv->write_byte(dev, msb, DAC_MSB_REG(i));
-               }
-       } else {
-               s->type         = COMEDI_SUBD_UNUSED;
-       }
-
-       /* 8255 dio */
-       s = &dev->subdevices[2];
-       if (dev->mmio)
-               ret = subdev_8255_mm_init(dev, s, NULL, DIO_BASE_REG);
-       else
-               ret = subdev_8255_init(dev, s, NULL, DIO_BASE_REG);
-       if (ret)
-               return ret;
-
-       /*  calibration subdevices for boards that have one */
-       s = &dev->subdevices[3];
-       if (board->is_labpc1200) {
-               s->type         = COMEDI_SUBD_CALIB;
-               s->subdev_flags = SDF_READABLE | SDF_WRITABLE | SDF_INTERNAL;
-               s->n_chan       = 16;
-               s->maxdata      = 0xff;
-               s->insn_read    = labpc_calib_insn_read;
-               s->insn_write   = labpc_calib_insn_write;
-
-               for (i = 0; i < s->n_chan; i++)
-                       write_caldac(dev, i, s->maxdata / 2);
-       } else {
-               s->type         = COMEDI_SUBD_UNUSED;
-       }
-
-       /* EEPROM */
-       s = &dev->subdevices[4];
-       if (board->is_labpc1200) {
-               s->type         = COMEDI_SUBD_MEMORY;
-               s->subdev_flags = SDF_READABLE | SDF_WRITABLE | SDF_INTERNAL;
-               s->n_chan       = EEPROM_SIZE;
-               s->maxdata      = 0xff;
-               s->insn_read    = labpc_eeprom_insn_read;
-               s->insn_write   = labpc_eeprom_insn_write;
-
-               for (i = 0; i < s->n_chan; i++)
-                       devpriv->eeprom_data[i] = labpc_eeprom_read(dev, i);
-       } else {
-               s->type         = COMEDI_SUBD_UNUSED;
-       }
-
-       return 0;
-}
-EXPORT_SYMBOL_GPL(labpc_common_attach);
-
-#if IS_ENABLED(CONFIG_COMEDI_NI_LABPC_ISA)
 static int labpc_attach(struct comedi_device *dev, struct comedi_devconfig *it)
 {
        struct labpc_private *devpriv;
@@ -1480,19 +128,7 @@ static struct comedi_driver labpc_driver = {
        .offset         = sizeof(struct labpc_boardinfo),
 };
 module_comedi_driver(labpc_driver);
-#else
-static int __init labpc_common_init(void)
-{
-       return 0;
-}
-module_init(labpc_common_init);
-
-static void __exit labpc_common_exit(void)
-{
-}
-module_exit(labpc_common_exit);
-#endif
 
 MODULE_AUTHOR("Comedi http://www.comedi.org");
-MODULE_DESCRIPTION("Comedi low-level driver");
+MODULE_DESCRIPTION("Comedi driver for NI Lab-PC ISA boards");
 MODULE_LICENSE("GPL");
diff --git a/drivers/staging/comedi/drivers/ni_labpc_common.c b/drivers/staging/comedi/drivers/ni_labpc_common.c
new file mode 100644 (file)
index 0000000..9e76a36
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@@ -0,0 +1,1387 @@
+/*
+ * comedi/drivers/ni_labpc_common.c
+ *
+ * Common support code for "ni_labpc", "ni_labpc_pci" and "ni_labpc_cs".
+ *
+ * Copyright (C) 2001-2003 Frank Mori Hess <fmhess@users.sourceforge.net>
+ *
+ * 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.
+ */
+
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/delay.h>
+
+#include "../comedidev.h"
+
+#include "8253.h"
+#include "8255.h"
+#include "comedi_fc.h"
+#include "ni_labpc.h"
+#include "ni_labpc_regs.h"
+#include "ni_labpc_isadma.h"
+
+enum scan_mode {
+       MODE_SINGLE_CHAN,
+       MODE_SINGLE_CHAN_INTERVAL,
+       MODE_MULT_CHAN_UP,
+       MODE_MULT_CHAN_DOWN,
+};
+
+static const struct comedi_lrange range_labpc_plus_ai = {
+       16, {
+               BIP_RANGE(5),
+               BIP_RANGE(4),
+               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(8),
+               UNI_RANGE(5),
+               UNI_RANGE(2),
+               UNI_RANGE(1),
+               UNI_RANGE(0.5),
+               UNI_RANGE(0.2),
+               UNI_RANGE(0.1)
+       }
+};
+
+static const struct comedi_lrange range_labpc_1200_ai = {
+       14, {
+               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 struct comedi_lrange range_labpc_ao = {
+       2, {
+               BIP_RANGE(5),
+               UNI_RANGE(10)
+       }
+};
+
+/* functions that do inb/outb and readb/writeb so we can use
+ * function pointers to decide which to use */
+static unsigned int labpc_inb(struct comedi_device *dev, unsigned long reg)
+{
+       return inb(dev->iobase + reg);
+}
+
+static void labpc_outb(struct comedi_device *dev,
+                      unsigned int byte, unsigned long reg)
+{
+       outb(byte, dev->iobase + reg);
+}
+
+static unsigned int labpc_readb(struct comedi_device *dev, unsigned long reg)
+{
+       return readb(dev->mmio + reg);
+}
+
+static void labpc_writeb(struct comedi_device *dev,
+                        unsigned int byte, unsigned long reg)
+{
+       writeb(byte, dev->mmio + reg);
+}
+
+static void labpc_counter_load(struct comedi_device *dev,
+                              unsigned long reg,
+                              unsigned int counter_number,
+                              unsigned int count,
+                              unsigned int mode)
+{
+       if (dev->mmio) {
+               i8254_mm_set_mode(dev->mmio + reg, 0, counter_number, mode);
+               i8254_mm_write(dev->mmio + reg, 0, counter_number, count);
+       } else {
+               i8254_set_mode(dev->iobase + reg, 0, counter_number, mode);
+               i8254_write(dev->iobase + reg, 0, counter_number, count);
+       }
+}
+
+static void labpc_counter_set_mode(struct comedi_device *dev,
+                                  unsigned long reg,
+                                  unsigned int counter_number,
+                                  unsigned int mode)
+{
+       if (dev->mmio)
+               i8254_mm_set_mode(dev->mmio + reg, 0, counter_number, mode);
+       else
+               i8254_set_mode(dev->iobase + reg, 0, counter_number, mode);
+}
+
+static int labpc_cancel(struct comedi_device *dev, struct comedi_subdevice *s)
+{
+       struct labpc_private *devpriv = dev->private;
+       unsigned long flags;
+
+       spin_lock_irqsave(&dev->spinlock, flags);
+       devpriv->cmd2 &= ~(CMD2_SWTRIG | CMD2_HWTRIG | CMD2_PRETRIG);
+       devpriv->write_byte(dev, devpriv->cmd2, CMD2_REG);
+       spin_unlock_irqrestore(&dev->spinlock, flags);
+
+       devpriv->cmd3 = 0;
+       devpriv->write_byte(dev, devpriv->cmd3, CMD3_REG);
+
+       return 0;
+}
+
+static void labpc_ai_set_chan_and_gain(struct comedi_device *dev,
+                                      enum scan_mode mode,
+                                      unsigned int chan,
+                                      unsigned int range,
+                                      unsigned int aref)
+{
+       const struct labpc_boardinfo *board = comedi_board(dev);
+       struct labpc_private *devpriv = dev->private;
+
+       if (board->is_labpc1200) {
+               /*
+                * The LabPC-1200 boards do not have a gain
+                * of '0x10'. Skip the range values that would
+                * result in this gain.
+                */
+               range += (range > 0) + (range > 7);
+       }
+
+       /* munge channel bits for differential/scan disabled mode */
+       if ((mode == MODE_SINGLE_CHAN || mode == MODE_SINGLE_CHAN_INTERVAL) &&
+           aref == AREF_DIFF)
+               chan *= 2;
+       devpriv->cmd1 = CMD1_MA(chan);
+       devpriv->cmd1 |= CMD1_GAIN(range);
+
+       devpriv->write_byte(dev, devpriv->cmd1, CMD1_REG);
+}
+
+static void labpc_setup_cmd6_reg(struct comedi_device *dev,
+                                struct comedi_subdevice *s,
+                                enum scan_mode mode,
+                                enum transfer_type xfer,
+                                unsigned int range,
+                                unsigned int aref,
+                                bool ena_intr)
+{
+       const struct labpc_boardinfo *board = comedi_board(dev);
+       struct labpc_private *devpriv = dev->private;
+
+       if (!board->is_labpc1200)
+               return;
+
+       /* reference inputs to ground or common? */
+       if (aref != AREF_GROUND)
+               devpriv->cmd6 |= CMD6_NRSE;
+       else
+               devpriv->cmd6 &= ~CMD6_NRSE;
+
+       /* bipolar or unipolar range? */
+       if (comedi_range_is_unipolar(s, range))
+               devpriv->cmd6 |= CMD6_ADCUNI;
+       else
+               devpriv->cmd6 &= ~CMD6_ADCUNI;
+
+       /*  interrupt on fifo half full? */
+       if (xfer == fifo_half_full_transfer)
+               devpriv->cmd6 |= CMD6_HFINTEN;
+       else
+               devpriv->cmd6 &= ~CMD6_HFINTEN;
+
+       /* enable interrupt on counter a1 terminal count? */
+       if (ena_intr)
+               devpriv->cmd6 |= CMD6_DQINTEN;
+       else
+               devpriv->cmd6 &= ~CMD6_DQINTEN;
+
+       /* are we scanning up or down through channels? */
+       if (mode == MODE_MULT_CHAN_UP)
+               devpriv->cmd6 |= CMD6_SCANUP;
+       else
+               devpriv->cmd6 &= ~CMD6_SCANUP;
+
+       devpriv->write_byte(dev, devpriv->cmd6, CMD6_REG);
+}
+
+static unsigned int labpc_read_adc_fifo(struct comedi_device *dev)
+{
+       struct labpc_private *devpriv = dev->private;
+       unsigned int lsb = devpriv->read_byte(dev, ADC_FIFO_REG);
+       unsigned int msb = devpriv->read_byte(dev, ADC_FIFO_REG);
+
+       return (msb << 8) | lsb;
+}
+
+static void labpc_clear_adc_fifo(struct comedi_device *dev)
+{
+       struct labpc_private *devpriv = dev->private;
+
+       devpriv->write_byte(dev, 0x1, ADC_FIFO_CLEAR_REG);
+       labpc_read_adc_fifo(dev);
+}
+
+static int labpc_ai_eoc(struct comedi_device *dev,
+                       struct comedi_subdevice *s,
+                       struct comedi_insn *insn,
+                       unsigned long context)
+{
+       struct labpc_private *devpriv = dev->private;
+
+       devpriv->stat1 = devpriv->read_byte(dev, STAT1_REG);
+       if (devpriv->stat1 & STAT1_DAVAIL)
+               return 0;
+       return -EBUSY;
+}
+
+static int labpc_ai_insn_read(struct comedi_device *dev,
+                             struct comedi_subdevice *s,
+                             struct comedi_insn *insn,
+                             unsigned int *data)
+{
+       struct labpc_private *devpriv = dev->private;
+       unsigned int chan = CR_CHAN(insn->chanspec);
+       unsigned int range = CR_RANGE(insn->chanspec);
+       unsigned int aref = CR_AREF(insn->chanspec);
+       int ret;
+       int i;
+
+       /* disable timed conversions, interrupt generation and dma */
+       labpc_cancel(dev, s);
+
+       labpc_ai_set_chan_and_gain(dev, MODE_SINGLE_CHAN, chan, range, aref);
+
+       labpc_setup_cmd6_reg(dev, s, MODE_SINGLE_CHAN, fifo_not_empty_transfer,
+                            range, aref, false);
+
+       /* setup cmd4 register */
+       devpriv->cmd4 = 0;
+       devpriv->cmd4 |= CMD4_ECLKRCV;
+       /* single-ended/differential */
+       if (aref == AREF_DIFF)
+               devpriv->cmd4 |= CMD4_SEDIFF;
+       devpriv->write_byte(dev, devpriv->cmd4, CMD4_REG);
+
+       /* initialize pacer counter to prevent any problems */
+       labpc_counter_set_mode(dev, COUNTER_A_BASE_REG, 0, I8254_MODE2);
+
+       labpc_clear_adc_fifo(dev);
+
+       for (i = 0; i < insn->n; i++) {
+               /* trigger conversion */
+               devpriv->write_byte(dev, 0x1, ADC_START_CONVERT_REG);
+
+               ret = comedi_timeout(dev, s, insn, labpc_ai_eoc, 0);
+               if (ret)
+                       return ret;
+
+               data[i] = labpc_read_adc_fifo(dev);
+       }
+
+       return insn->n;
+}
+
+static bool labpc_use_continuous_mode(const struct comedi_cmd *cmd,
+                                     enum scan_mode mode)
+{
+       if (mode == MODE_SINGLE_CHAN || cmd->scan_begin_src == TRIG_FOLLOW)
+               return true;
+
+       return false;
+}
+
+static unsigned int labpc_ai_convert_period(const struct comedi_cmd *cmd,
+                                           enum scan_mode mode)
+{
+       if (cmd->convert_src != TRIG_TIMER)
+               return 0;
+
+       if (mode == MODE_SINGLE_CHAN && cmd->scan_begin_src == TRIG_TIMER)
+               return cmd->scan_begin_arg;
+
+       return cmd->convert_arg;
+}
+
+static void labpc_set_ai_convert_period(struct comedi_cmd *cmd,
+                                       enum scan_mode mode, unsigned int ns)
+{
+       if (cmd->convert_src != TRIG_TIMER)
+               return;
+
+       if (mode == MODE_SINGLE_CHAN &&
+           cmd->scan_begin_src == TRIG_TIMER) {
+               cmd->scan_begin_arg = ns;
+               if (cmd->convert_arg > cmd->scan_begin_arg)
+                       cmd->convert_arg = cmd->scan_begin_arg;
+       } else {
+               cmd->convert_arg = ns;
+       }
+}
+
+static unsigned int labpc_ai_scan_period(const struct comedi_cmd *cmd,
+                                        enum scan_mode mode)
+{
+       if (cmd->scan_begin_src != TRIG_TIMER)
+               return 0;
+
+       if (mode == MODE_SINGLE_CHAN && cmd->convert_src == TRIG_TIMER)
+               return 0;
+
+       return cmd->scan_begin_arg;
+}
+
+static void labpc_set_ai_scan_period(struct comedi_cmd *cmd,
+                                    enum scan_mode mode, unsigned int ns)
+{
+       if (cmd->scan_begin_src != TRIG_TIMER)
+               return;
+
+       if (mode == MODE_SINGLE_CHAN && cmd->convert_src == TRIG_TIMER)
+               return;
+
+       cmd->scan_begin_arg = ns;
+}
+
+/* figures out what counter values to use based on command */
+static void labpc_adc_timing(struct comedi_device *dev, struct comedi_cmd *cmd,
+                            enum scan_mode mode)
+{
+       struct labpc_private *devpriv = dev->private;
+       /* max value for 16 bit counter in mode 2 */
+       const int max_counter_value = 0x10000;
+       /* min value for 16 bit counter in mode 2 */
+       const int min_counter_value = 2;
+       unsigned int base_period;
+       unsigned int scan_period;
+       unsigned int convert_period;
+
+       /*
+        * if both convert and scan triggers are TRIG_TIMER, then they
+        * both rely on counter b0
+        */
+       convert_period = labpc_ai_convert_period(cmd, mode);
+       scan_period = labpc_ai_scan_period(cmd, mode);
+       if (convert_period && scan_period) {
+               /*
+                * pick the lowest b0 divisor value we can (for maximum input
+                * clock speed on convert and scan counters)
+                */
+               devpriv->divisor_b0 = (scan_period - 1) /
+                   (I8254_OSC_BASE_2MHZ * max_counter_value) + 1;
+               if (devpriv->divisor_b0 < min_counter_value)
+                       devpriv->divisor_b0 = min_counter_value;
+               if (devpriv->divisor_b0 > max_counter_value)
+                       devpriv->divisor_b0 = max_counter_value;
+
+               base_period = I8254_OSC_BASE_2MHZ * devpriv->divisor_b0;
+
+               /*  set a0 for conversion frequency and b1 for scan frequency */
+               switch (cmd->flags & TRIG_ROUND_MASK) {
+               default:
+               case TRIG_ROUND_NEAREST:
+                       devpriv->divisor_a0 =
+                           (convert_period + (base_period / 2)) / base_period;
+                       devpriv->divisor_b1 =
+                           (scan_period + (base_period / 2)) / base_period;
+                       break;
+               case TRIG_ROUND_UP:
+                       devpriv->divisor_a0 =
+                           (convert_period + (base_period - 1)) / base_period;
+                       devpriv->divisor_b1 =
+                           (scan_period + (base_period - 1)) / base_period;
+                       break;
+               case TRIG_ROUND_DOWN:
+                       devpriv->divisor_a0 = convert_period / base_period;
+                       devpriv->divisor_b1 = scan_period / base_period;
+                       break;
+               }
+               /*  make sure a0 and b1 values are acceptable */
+               if (devpriv->divisor_a0 < min_counter_value)
+                       devpriv->divisor_a0 = min_counter_value;
+               if (devpriv->divisor_a0 > max_counter_value)
+                       devpriv->divisor_a0 = max_counter_value;
+               if (devpriv->divisor_b1 < min_counter_value)
+                       devpriv->divisor_b1 = min_counter_value;
+               if (devpriv->divisor_b1 > max_counter_value)
+                       devpriv->divisor_b1 = max_counter_value;
+               /*  write corrected timings to command */
+               labpc_set_ai_convert_period(cmd, mode,
+                                           base_period * devpriv->divisor_a0);
+               labpc_set_ai_scan_period(cmd, mode,
+                                        base_period * devpriv->divisor_b1);
+               /*
+                * if only one TRIG_TIMER is used, we can employ the generic
+                * cascaded timing functions
+                */
+       } else if (scan_period) {
+               /*
+                * calculate cascaded counter values
+                * that give desired scan timing
+                */
+               i8253_cascade_ns_to_timer(I8254_OSC_BASE_2MHZ,
+                                         &devpriv->divisor_b1,
+                                         &devpriv->divisor_b0,
+                                         &scan_period, cmd->flags);
+               labpc_set_ai_scan_period(cmd, mode, scan_period);
+       } else if (convert_period) {
+               /*
+                * calculate cascaded counter values
+                * that give desired conversion timing
+                */
+               i8253_cascade_ns_to_timer(I8254_OSC_BASE_2MHZ,
+                                         &devpriv->divisor_a0,
+                                         &devpriv->divisor_b0,
+                                         &convert_period, cmd->flags);
+               labpc_set_ai_convert_period(cmd, mode, convert_period);
+       }
+}
+
+static enum scan_mode labpc_ai_scan_mode(const struct comedi_cmd *cmd)
+{
+       unsigned int chan0;
+       unsigned int chan1;
+
+       if (cmd->chanlist_len == 1)
+               return MODE_SINGLE_CHAN;
+
+       /* chanlist may be NULL during cmdtest */
+       if (cmd->chanlist == NULL)
+               return MODE_MULT_CHAN_UP;
+
+       chan0 = CR_CHAN(cmd->chanlist[0]);
+       chan1 = CR_CHAN(cmd->chanlist[1]);
+
+       if (chan0 < chan1)
+               return MODE_MULT_CHAN_UP;
+
+       if (chan0 > chan1)
+               return MODE_MULT_CHAN_DOWN;
+
+       return MODE_SINGLE_CHAN_INTERVAL;
+}
+
+static int labpc_ai_check_chanlist(struct comedi_device *dev,
+                                  struct comedi_subdevice *s,
+                                  struct comedi_cmd *cmd)
+{
+       enum scan_mode mode = labpc_ai_scan_mode(cmd);
+       unsigned int chan0 = CR_CHAN(cmd->chanlist[0]);
+       unsigned int range0 = CR_RANGE(cmd->chanlist[0]);
+       unsigned int aref0 = CR_AREF(cmd->chanlist[0]);
+       int i;
+
+       if (mode == MODE_SINGLE_CHAN)
+               return 0;
+
+       for (i = 0; i < cmd->chanlist_len; i++) {
+               unsigned int chan = CR_CHAN(cmd->chanlist[i]);
+               unsigned int range = CR_RANGE(cmd->chanlist[i]);
+               unsigned int aref = CR_AREF(cmd->chanlist[i]);
+
+               switch (mode) {
+               case MODE_SINGLE_CHAN:
+                       break;
+               case MODE_SINGLE_CHAN_INTERVAL:
+                       if (chan != chan0) {
+                               dev_dbg(dev->class_dev,
+                                       "channel scanning order specified in chanlist is not supported by hardware\n");
+                               return -EINVAL;
+                       }
+                       break;
+               case MODE_MULT_CHAN_UP:
+                       if (chan != i) {
+                               dev_dbg(dev->class_dev,
+                                       "channel scanning order specified in chanlist is not supported by hardware\n");
+                               return -EINVAL;
+                       }
+                       break;
+               case MODE_MULT_CHAN_DOWN:
+                       if (chan != (cmd->chanlist_len - i - 1)) {
+                               dev_dbg(dev->class_dev,
+                                       "channel scanning order specified in chanlist is not supported by hardware\n");
+                               return -EINVAL;
+                       }
+                       break;
+               }
+
+               if (range != range0) {
+                       dev_dbg(dev->class_dev,
+                               "entries in chanlist must all have the same range\n");
+                       return -EINVAL;
+               }
+
+               if (aref != aref0) {
+                       dev_dbg(dev->class_dev,
+                               "entries in chanlist must all have the same reference\n");
+                       return -EINVAL;
+               }
+       }
+
+       return 0;
+}
+
+static int labpc_ai_cmdtest(struct comedi_device *dev,
+                           struct comedi_subdevice *s, struct comedi_cmd *cmd)
+{
+       const struct labpc_boardinfo *board = comedi_board(dev);
+       int err = 0;
+       int tmp, tmp2;
+       unsigned int stop_mask;
+       enum scan_mode mode;
+
+       /* Step 1 : check if triggers are trivially valid */
+
+       err |= cfc_check_trigger_src(&cmd->start_src, TRIG_NOW | TRIG_EXT);
+       err |= cfc_check_trigger_src(&cmd->scan_begin_src,
+                                       TRIG_TIMER | TRIG_FOLLOW | TRIG_EXT);
+       err |= cfc_check_trigger_src(&cmd->convert_src, TRIG_TIMER | TRIG_EXT);
+       err |= cfc_check_trigger_src(&cmd->scan_end_src, TRIG_COUNT);
+
+       stop_mask = TRIG_COUNT | TRIG_NONE;
+       if (board->is_labpc1200)
+               stop_mask |= TRIG_EXT;
+       err |= cfc_check_trigger_src(&cmd->stop_src, stop_mask);
+
+       if (err)
+               return 1;
+
+       /* Step 2a : make sure trigger sources are unique */
+
+       err |= cfc_check_trigger_is_unique(cmd->start_src);
+       err |= cfc_check_trigger_is_unique(cmd->scan_begin_src);
+       err |= cfc_check_trigger_is_unique(cmd->convert_src);
+       err |= cfc_check_trigger_is_unique(cmd->stop_src);
+
+       /* Step 2b : and mutually compatible */
+
+       /* can't have external stop and start triggers at once */
+       if (cmd->start_src == TRIG_EXT && cmd->stop_src == TRIG_EXT)
+               err++;
+
+       if (err)
+               return 2;
+
+       /* Step 3: check if arguments are trivially valid */
+
+       switch (cmd->start_src) {
+       case TRIG_NOW:
+               err |= cfc_check_trigger_arg_is(&cmd->start_arg, 0);
+               break;
+       case TRIG_EXT:
+               /* start_arg value is ignored */
+               break;
+       }
+
+       if (!cmd->chanlist_len)
+               err |= -EINVAL;
+       err |= cfc_check_trigger_arg_is(&cmd->scan_end_arg, cmd->chanlist_len);
+
+       if (cmd->convert_src == TRIG_TIMER)
+               err |= cfc_check_trigger_arg_min(&cmd->convert_arg,
+                                                board->ai_speed);
+
+       /* make sure scan timing is not too fast */
+       if (cmd->scan_begin_src == TRIG_TIMER) {
+               if (cmd->convert_src == TRIG_TIMER)
+                       err |= cfc_check_trigger_arg_min(&cmd->scan_begin_arg,
+                                       cmd->convert_arg * cmd->chanlist_len);
+               err |= cfc_check_trigger_arg_min(&cmd->scan_begin_arg,
+                               board->ai_speed * cmd->chanlist_len);
+       }
+
+       switch (cmd->stop_src) {
+       case TRIG_COUNT:
+               err |= cfc_check_trigger_arg_min(&cmd->stop_arg, 1);
+               break;
+       case TRIG_NONE:
+               err |= cfc_check_trigger_arg_is(&cmd->stop_arg, 0);
+               break;
+               /*
+                * TRIG_EXT doesn't care since it doesn't
+                * trigger off a numbered channel
+                */
+       default:
+               break;
+       }
+
+       if (err)
+               return 3;
+
+       /* step 4: fix up any arguments */
+
+       tmp = cmd->convert_arg;
+       tmp2 = cmd->scan_begin_arg;
+       mode = labpc_ai_scan_mode(cmd);
+       labpc_adc_timing(dev, cmd, mode);
+       if (tmp != cmd->convert_arg || tmp2 != 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 |= labpc_ai_check_chanlist(dev, s, cmd);
+
+       if (err)
+               return 5;
+
+       return 0;
+}
+
+static int labpc_ai_cmd(struct comedi_device *dev, struct comedi_subdevice *s)
+{
+       const struct labpc_boardinfo *board = comedi_board(dev);
+       struct labpc_private *devpriv = dev->private;
+       struct comedi_async *async = s->async;
+       struct comedi_cmd *cmd = &async->cmd;
+       enum scan_mode mode = labpc_ai_scan_mode(cmd);
+       unsigned int chanspec = (mode == MODE_MULT_CHAN_UP) ?
+                               cmd->chanlist[cmd->chanlist_len - 1] :
+                               cmd->chanlist[0];
+       unsigned int chan = CR_CHAN(chanspec);
+       unsigned int range = CR_RANGE(chanspec);
+       unsigned int aref = CR_AREF(chanspec);
+       enum transfer_type xfer;
+       unsigned long flags;
+
+       /* make sure board is disabled before setting up acquisition */
+       labpc_cancel(dev, s);
+
+       /*  initialize software conversion count */
+       if (cmd->stop_src == TRIG_COUNT)
+               devpriv->count = cmd->stop_arg * cmd->chanlist_len;
+
+       /*  setup hardware conversion counter */
+       if (cmd->stop_src == TRIG_EXT) {
+               /*
+                * load counter a1 with count of 3
+                * (pc+ manual says this is minimum allowed) using mode 0
+                */
+               labpc_counter_load(dev, COUNTER_A_BASE_REG,
+                                  1, 3, I8254_MODE0);
+       } else  {
+               /* just put counter a1 in mode 0 to set its output low */
+               labpc_counter_set_mode(dev, COUNTER_A_BASE_REG, 1, I8254_MODE0);
+       }
+
+       /* figure out what method we will use to transfer data */
+       if (labpc_have_dma_chan(dev) &&
+           /* dma unsafe at RT priority,
+            * and too much setup time for TRIG_WAKE_EOS */
+           (cmd->flags & (TRIG_WAKE_EOS | TRIG_RT)) == 0)
+               xfer = isa_dma_transfer;
+       else if (/* pc-plus has no fifo-half full interrupt */
+                board->is_labpc1200 &&
+                /* wake-end-of-scan should interrupt on fifo not empty */
+                (cmd->flags & TRIG_WAKE_EOS) == 0 &&
+                /* make sure we are taking more than just a few points */
+                (cmd->stop_src != TRIG_COUNT || devpriv->count > 256))
+               xfer = fifo_half_full_transfer;
+       else
+               xfer = fifo_not_empty_transfer;
+       devpriv->current_transfer = xfer;
+
+       labpc_ai_set_chan_and_gain(dev, mode, chan, range, aref);
+
+       labpc_setup_cmd6_reg(dev, s, mode, xfer, range, aref,
+                            (cmd->stop_src == TRIG_EXT));
+
+       /* manual says to set scan enable bit on second pass */
+       if (mode == MODE_MULT_CHAN_UP || mode == MODE_MULT_CHAN_DOWN) {
+               devpriv->cmd1 |= CMD1_SCANEN;
+               /* need a brief delay before enabling scan, or scan
+                * list will get screwed when you switch
+                * between scan up to scan down mode - dunno why */
+               udelay(1);
+               devpriv->write_byte(dev, devpriv->cmd1, CMD1_REG);
+       }
+
+       devpriv->write_byte(dev, cmd->chanlist_len, INTERVAL_COUNT_REG);
+       /*  load count */
+       devpriv->write_byte(dev, 0x1, INTERVAL_STROBE_REG);
+
+       if (cmd->convert_src == TRIG_TIMER ||
+           cmd->scan_begin_src == TRIG_TIMER) {
+               /*  set up pacing */
+               labpc_adc_timing(dev, cmd, mode);
+               /*  load counter b0 in mode 3 */
+               labpc_counter_load(dev, COUNTER_B_BASE_REG,
+                                  0, devpriv->divisor_b0, I8254_MODE3);
+       }
+       /*  set up conversion pacing */
+       if (labpc_ai_convert_period(cmd, mode)) {
+               /*  load counter a0 in mode 2 */
+               labpc_counter_load(dev, COUNTER_A_BASE_REG,
+                                  0, devpriv->divisor_a0, I8254_MODE2);
+       } else {
+               /* initialize pacer counter to prevent any problems */
+               labpc_counter_set_mode(dev, COUNTER_A_BASE_REG, 0, I8254_MODE2);
+       }
+
+       /*  set up scan pacing */
+       if (labpc_ai_scan_period(cmd, mode)) {
+               /*  load counter b1 in mode 2 */
+               labpc_counter_load(dev, COUNTER_B_BASE_REG,
+                                  1, devpriv->divisor_b1, I8254_MODE2);
+       }
+
+       labpc_clear_adc_fifo(dev);
+
+       if (xfer == isa_dma_transfer)
+               labpc_setup_dma(dev, s);
+
+       /*  enable error interrupts */
+       devpriv->cmd3 |= CMD3_ERRINTEN;
+       /*  enable fifo not empty interrupt? */
+       if (xfer == fifo_not_empty_transfer)
+               devpriv->cmd3 |= CMD3_FIFOINTEN;
+       devpriv->write_byte(dev, devpriv->cmd3, CMD3_REG);
+
+       /*  setup any external triggering/pacing (cmd4 register) */
+       devpriv->cmd4 = 0;
+       if (cmd->convert_src != TRIG_EXT)
+               devpriv->cmd4 |= CMD4_ECLKRCV;
+       /* XXX should discard first scan when using interval scanning
+        * since manual says it is not synced with scan clock */
+       if (!labpc_use_continuous_mode(cmd, mode)) {
+               devpriv->cmd4 |= CMD4_INTSCAN;
+               if (cmd->scan_begin_src == TRIG_EXT)
+                       devpriv->cmd4 |= CMD4_EOIRCV;
+       }
+       /*  single-ended/differential */
+       if (aref == AREF_DIFF)
+               devpriv->cmd4 |= CMD4_SEDIFF;
+       devpriv->write_byte(dev, devpriv->cmd4, CMD4_REG);
+
+       /*  startup acquisition */
+
+       spin_lock_irqsave(&dev->spinlock, flags);
+
+       /* use 2 cascaded counters for pacing */
+       devpriv->cmd2 |= CMD2_TBSEL;
+
+       devpriv->cmd2 &= ~(CMD2_SWTRIG | CMD2_HWTRIG | CMD2_PRETRIG);
+       if (cmd->start_src == TRIG_EXT)
+               devpriv->cmd2 |= CMD2_HWTRIG;
+       else
+               devpriv->cmd2 |= CMD2_SWTRIG;
+       if (cmd->stop_src == TRIG_EXT)
+               devpriv->cmd2 |= (CMD2_HWTRIG | CMD2_PRETRIG);
+
+       devpriv->write_byte(dev, devpriv->cmd2, CMD2_REG);
+
+       spin_unlock_irqrestore(&dev->spinlock, flags);
+
+       return 0;
+}
+
+/* read all available samples from ai fifo */
+static int labpc_drain_fifo(struct comedi_device *dev)
+{
+       struct labpc_private *devpriv = dev->private;
+       struct comedi_async *async = dev->read_subdev->async;
+       struct comedi_cmd *cmd = &async->cmd;
+       unsigned short data;
+       const int timeout = 10000;
+       unsigned int i;
+
+       devpriv->stat1 = devpriv->read_byte(dev, STAT1_REG);
+
+       for (i = 0; (devpriv->stat1 & STAT1_DAVAIL) && i < timeout;
+            i++) {
+               /*  quit if we have all the data we want */
+               if (cmd->stop_src == TRIG_COUNT) {
+                       if (devpriv->count == 0)
+                               break;
+                       devpriv->count--;
+               }
+               data = labpc_read_adc_fifo(dev);
+               cfc_write_to_buffer(dev->read_subdev, data);
+               devpriv->stat1 = devpriv->read_byte(dev, STAT1_REG);
+       }
+       if (i == timeout) {
+               dev_err(dev->class_dev, "ai timeout, fifo never empties\n");
+               async->events |= COMEDI_CB_ERROR | COMEDI_CB_EOA;
+               return -1;
+       }
+
+       return 0;
+}
+
+/* makes sure all data acquired by board is transferred to comedi (used
+ * when acquisition is terminated by stop_src == TRIG_EXT). */
+static void labpc_drain_dregs(struct comedi_device *dev)
+{
+       struct labpc_private *devpriv = dev->private;
+
+       if (devpriv->current_transfer == isa_dma_transfer)
+               labpc_drain_dma(dev);
+
+       labpc_drain_fifo(dev);
+}
+
+/* interrupt service routine */
+static irqreturn_t labpc_interrupt(int irq, void *d)
+{
+       struct comedi_device *dev = d;
+       const struct labpc_boardinfo *board = comedi_board(dev);
+       struct labpc_private *devpriv = dev->private;
+       struct comedi_subdevice *s = dev->read_subdev;
+       struct comedi_async *async;
+       struct comedi_cmd *cmd;
+
+       if (!dev->attached) {
+               dev_err(dev->class_dev, "premature interrupt\n");
+               return IRQ_HANDLED;
+       }
+
+       async = s->async;
+       cmd = &async->cmd;
+
+       /* read board status */
+       devpriv->stat1 = devpriv->read_byte(dev, STAT1_REG);
+       if (board->is_labpc1200)
+               devpriv->stat2 = devpriv->read_byte(dev, STAT2_REG);
+
+       if ((devpriv->stat1 & (STAT1_GATA0 | STAT1_CNTINT | STAT1_OVERFLOW |
+                              STAT1_OVERRUN | STAT1_DAVAIL)) == 0 &&
+           (devpriv->stat2 & STAT2_OUTA1) == 0 &&
+           (devpriv->stat2 & STAT2_FIFONHF)) {
+               return IRQ_NONE;
+       }
+
+       if (devpriv->stat1 & STAT1_OVERRUN) {
+               /* clear error interrupt */
+               devpriv->write_byte(dev, 0x1, ADC_FIFO_CLEAR_REG);
+               async->events |= COMEDI_CB_ERROR | COMEDI_CB_EOA;
+               cfc_handle_events(dev, s);
+               dev_err(dev->class_dev, "overrun\n");
+               return IRQ_HANDLED;
+       }
+
+       if (devpriv->current_transfer == isa_dma_transfer)
+               labpc_handle_dma_status(dev);
+       else
+               labpc_drain_fifo(dev);
+
+       if (devpriv->stat1 & STAT1_CNTINT) {
+               dev_err(dev->class_dev, "handled timer interrupt?\n");
+               /*  clear it */
+               devpriv->write_byte(dev, 0x1, TIMER_CLEAR_REG);
+       }
+
+       if (devpriv->stat1 & STAT1_OVERFLOW) {
+               /*  clear error interrupt */
+               devpriv->write_byte(dev, 0x1, ADC_FIFO_CLEAR_REG);
+               async->events |= COMEDI_CB_ERROR | COMEDI_CB_EOA;
+               cfc_handle_events(dev, s);
+               dev_err(dev->class_dev, "overflow\n");
+               return IRQ_HANDLED;
+       }
+       /*  handle external stop trigger */
+       if (cmd->stop_src == TRIG_EXT) {
+               if (devpriv->stat2 & STAT2_OUTA1) {
+                       labpc_drain_dregs(dev);
+                       async->events |= COMEDI_CB_EOA;
+               }
+       }
+
+       /* TRIG_COUNT end of acquisition */
+       if (cmd->stop_src == TRIG_COUNT) {
+               if (devpriv->count == 0)
+                       async->events |= COMEDI_CB_EOA;
+       }
+
+       cfc_handle_events(dev, s);
+       return IRQ_HANDLED;
+}
+
+static int labpc_ao_insn_write(struct comedi_device *dev,
+                              struct comedi_subdevice *s,
+                              struct comedi_insn *insn,
+                              unsigned int *data)
+{
+       const struct labpc_boardinfo *board = comedi_board(dev);
+       struct labpc_private *devpriv = dev->private;
+       int channel, range;
+       unsigned long flags;
+       int lsb, msb;
+
+       channel = CR_CHAN(insn->chanspec);
+
+       /* turn off pacing of analog output channel */
+       /* note: hardware bug in daqcard-1200 means pacing cannot
+        * be independently enabled/disabled for its the two channels */
+       spin_lock_irqsave(&dev->spinlock, flags);
+       devpriv->cmd2 &= ~CMD2_LDAC(channel);
+       devpriv->write_byte(dev, devpriv->cmd2, CMD2_REG);
+       spin_unlock_irqrestore(&dev->spinlock, flags);
+
+       /* set range */
+       if (board->is_labpc1200) {
+               range = CR_RANGE(insn->chanspec);
+               if (comedi_range_is_unipolar(s, range))
+                       devpriv->cmd6 |= CMD6_DACUNI(channel);
+               else
+                       devpriv->cmd6 &= ~CMD6_DACUNI(channel);
+               /*  write to register */
+               devpriv->write_byte(dev, devpriv->cmd6, CMD6_REG);
+       }
+       /* send data */
+       lsb = data[0] & 0xff;
+       msb = (data[0] >> 8) & 0xff;
+       devpriv->write_byte(dev, lsb, DAC_LSB_REG(channel));
+       devpriv->write_byte(dev, msb, DAC_MSB_REG(channel));
+
+       /* remember value for readback */
+       devpriv->ao_value[channel] = data[0];
+
+       return 1;
+}
+
+static int labpc_ao_insn_read(struct comedi_device *dev,
+                             struct comedi_subdevice *s,
+                             struct comedi_insn *insn,
+                             unsigned int *data)
+{
+       struct labpc_private *devpriv = dev->private;
+
+       data[0] = devpriv->ao_value[CR_CHAN(insn->chanspec)];
+
+       return 1;
+}
+
+/* lowlevel write to eeprom/dac */
+static void labpc_serial_out(struct comedi_device *dev, unsigned int value,
+                            unsigned int value_width)
+{
+       struct labpc_private *devpriv = dev->private;
+       int i;
+
+       for (i = 1; i <= value_width; i++) {
+               /*  clear serial clock */
+               devpriv->cmd5 &= ~CMD5_SCLK;
+               /*  send bits most significant bit first */
+               if (value & (1 << (value_width - i)))
+                       devpriv->cmd5 |= CMD5_SDATA;
+               else
+                       devpriv->cmd5 &= ~CMD5_SDATA;
+               udelay(1);
+               devpriv->write_byte(dev, devpriv->cmd5, CMD5_REG);
+               /*  set clock to load bit */
+               devpriv->cmd5 |= CMD5_SCLK;
+               udelay(1);
+               devpriv->write_byte(dev, devpriv->cmd5, CMD5_REG);
+       }
+}
+
+/* lowlevel read from eeprom */
+static unsigned int labpc_serial_in(struct comedi_device *dev)
+{
+       struct labpc_private *devpriv = dev->private;
+       unsigned int value = 0;
+       int i;
+       const int value_width = 8;      /*  number of bits wide values are */
+
+       for (i = 1; i <= value_width; i++) {
+               /*  set serial clock */
+               devpriv->cmd5 |= CMD5_SCLK;
+               udelay(1);
+               devpriv->write_byte(dev, devpriv->cmd5, CMD5_REG);
+               /*  clear clock bit */
+               devpriv->cmd5 &= ~CMD5_SCLK;
+               udelay(1);
+               devpriv->write_byte(dev, devpriv->cmd5, CMD5_REG);
+               /*  read bits most significant bit first */
+               udelay(1);
+               devpriv->stat2 = devpriv->read_byte(dev, STAT2_REG);
+               if (devpriv->stat2 & STAT2_PROMOUT)
+                       value |= 1 << (value_width - i);
+       }
+
+       return value;
+}
+
+static unsigned int labpc_eeprom_read(struct comedi_device *dev,
+                                     unsigned int address)
+{
+       struct labpc_private *devpriv = dev->private;
+       unsigned int value;
+       /*  bits to tell eeprom to expect a read */
+       const int read_instruction = 0x3;
+       /*  8 bit write lengths to eeprom */
+       const int write_length = 8;
+
+       /*  enable read/write to eeprom */
+       devpriv->cmd5 &= ~CMD5_EEPROMCS;
+       udelay(1);
+       devpriv->write_byte(dev, devpriv->cmd5, CMD5_REG);
+       devpriv->cmd5 |= (CMD5_EEPROMCS | CMD5_WRTPRT);
+       udelay(1);
+       devpriv->write_byte(dev, devpriv->cmd5, CMD5_REG);
+
+       /*  send read instruction */
+       labpc_serial_out(dev, read_instruction, write_length);
+       /*  send 8 bit address to read from */
+       labpc_serial_out(dev, address, write_length);
+       /*  read result */
+       value = labpc_serial_in(dev);
+
+       /*  disable read/write to eeprom */
+       devpriv->cmd5 &= ~(CMD5_EEPROMCS | CMD5_WRTPRT);
+       udelay(1);
+       devpriv->write_byte(dev, devpriv->cmd5, CMD5_REG);
+
+       return value;
+}
+
+static unsigned int labpc_eeprom_read_status(struct comedi_device *dev)
+{
+       struct labpc_private *devpriv = dev->private;
+       unsigned int value;
+       const int read_status_instruction = 0x5;
+       const int write_length = 8;     /*  8 bit write lengths to eeprom */
+
+       /*  enable read/write to eeprom */
+       devpriv->cmd5 &= ~CMD5_EEPROMCS;
+       udelay(1);
+       devpriv->write_byte(dev, devpriv->cmd5, CMD5_REG);
+       devpriv->cmd5 |= (CMD5_EEPROMCS | CMD5_WRTPRT);
+       udelay(1);
+       devpriv->write_byte(dev, devpriv->cmd5, CMD5_REG);
+
+       /*  send read status instruction */
+       labpc_serial_out(dev, read_status_instruction, write_length);
+       /*  read result */
+       value = labpc_serial_in(dev);
+
+       /*  disable read/write to eeprom */
+       devpriv->cmd5 &= ~(CMD5_EEPROMCS | CMD5_WRTPRT);
+       udelay(1);
+       devpriv->write_byte(dev, devpriv->cmd5, CMD5_REG);
+
+       return value;
+}
+
+static int labpc_eeprom_write(struct comedi_device *dev,
+                             unsigned int address, unsigned int value)
+{
+       struct labpc_private *devpriv = dev->private;
+       const int write_enable_instruction = 0x6;
+       const int write_instruction = 0x2;
+       const int write_length = 8;     /*  8 bit write lengths to eeprom */
+       const int write_in_progress_bit = 0x1;
+       const int timeout = 10000;
+       int i;
+
+       /*  make sure there isn't already a write in progress */
+       for (i = 0; i < timeout; i++) {
+               if ((labpc_eeprom_read_status(dev) & write_in_progress_bit) ==
+                   0)
+                       break;
+       }
+       if (i == timeout) {
+               dev_err(dev->class_dev, "eeprom write timed out\n");
+               return -ETIME;
+       }
+       /*  update software copy of eeprom */
+       devpriv->eeprom_data[address] = value;
+
+       /*  enable read/write to eeprom */
+       devpriv->cmd5 &= ~CMD5_EEPROMCS;
+       udelay(1);
+       devpriv->write_byte(dev, devpriv->cmd5, CMD5_REG);
+       devpriv->cmd5 |= (CMD5_EEPROMCS | CMD5_WRTPRT);
+       udelay(1);
+       devpriv->write_byte(dev, devpriv->cmd5, CMD5_REG);
+
+       /*  send write_enable instruction */
+       labpc_serial_out(dev, write_enable_instruction, write_length);
+       devpriv->cmd5 &= ~CMD5_EEPROMCS;
+       udelay(1);
+       devpriv->write_byte(dev, devpriv->cmd5, CMD5_REG);
+
+       /*  send write instruction */
+       devpriv->cmd5 |= CMD5_EEPROMCS;
+       udelay(1);
+       devpriv->write_byte(dev, devpriv->cmd5, CMD5_REG);
+       labpc_serial_out(dev, write_instruction, write_length);
+       /*  send 8 bit address to write to */
+       labpc_serial_out(dev, address, write_length);
+       /*  write value */
+       labpc_serial_out(dev, value, write_length);
+       devpriv->cmd5 &= ~CMD5_EEPROMCS;
+       udelay(1);
+       devpriv->write_byte(dev, devpriv->cmd5, CMD5_REG);
+
+       /*  disable read/write to eeprom */
+       devpriv->cmd5 &= ~(CMD5_EEPROMCS | CMD5_WRTPRT);
+       udelay(1);
+       devpriv->write_byte(dev, devpriv->cmd5, CMD5_REG);
+
+       return 0;
+}
+
+/* writes to 8 bit calibration dacs */
+static void write_caldac(struct comedi_device *dev, unsigned int channel,
+                        unsigned int value)
+{
+       struct labpc_private *devpriv = dev->private;
+
+       if (value == devpriv->caldac[channel])
+               return;
+       devpriv->caldac[channel] = value;
+
+       /*  clear caldac load bit and make sure we don't write to eeprom */
+       devpriv->cmd5 &= ~(CMD5_CALDACLD | CMD5_EEPROMCS | CMD5_WRTPRT);
+       udelay(1);
+       devpriv->write_byte(dev, devpriv->cmd5, CMD5_REG);
+
+       /*  write 4 bit channel */
+       labpc_serial_out(dev, channel, 4);
+       /*  write 8 bit caldac value */
+       labpc_serial_out(dev, value, 8);
+
+       /*  set and clear caldac bit to load caldac value */
+       devpriv->cmd5 |= CMD5_CALDACLD;
+       udelay(1);
+       devpriv->write_byte(dev, devpriv->cmd5, CMD5_REG);
+       devpriv->cmd5 &= ~CMD5_CALDACLD;
+       udelay(1);
+       devpriv->write_byte(dev, devpriv->cmd5, CMD5_REG);
+}
+
+static int labpc_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);
+
+       /*
+        * Only write the last data value to the caldac. Preceding
+        * data would be overwritten anyway.
+        */
+       if (insn->n > 0)
+               write_caldac(dev, chan, data[insn->n - 1]);
+
+       return insn->n;
+}
+
+static int labpc_calib_insn_read(struct comedi_device *dev,
+                                struct comedi_subdevice *s,
+                                struct comedi_insn *insn,
+                                unsigned int *data)
+{
+       struct labpc_private *devpriv = dev->private;
+       unsigned int chan = CR_CHAN(insn->chanspec);
+       int i;
+
+       for (i = 0; i < insn->n; i++)
+               data[i] = devpriv->caldac[chan];
+
+       return insn->n;
+}
+
+static int labpc_eeprom_insn_write(struct comedi_device *dev,
+                                  struct comedi_subdevice *s,
+                                  struct comedi_insn *insn,
+                                  unsigned int *data)
+{
+       unsigned int chan = CR_CHAN(insn->chanspec);
+       int ret;
+
+       /* only allow writes to user area of eeprom */
+       if (chan < 16 || chan > 127)
+               return -EINVAL;
+
+       /*
+        * Only write the last data value to the eeprom. Preceding
+        * data would be overwritten anyway.
+        */
+       if (insn->n > 0) {
+               ret = labpc_eeprom_write(dev, chan, data[insn->n - 1]);
+               if (ret)
+                       return ret;
+       }
+
+       return insn->n;
+}
+
+static int labpc_eeprom_insn_read(struct comedi_device *dev,
+                                 struct comedi_subdevice *s,
+                                 struct comedi_insn *insn,
+                                 unsigned int *data)
+{
+       struct labpc_private *devpriv = dev->private;
+       unsigned int chan = CR_CHAN(insn->chanspec);
+       int i;
+
+       for (i = 0; i < insn->n; i++)
+               data[i] = devpriv->eeprom_data[chan];
+
+       return insn->n;
+}
+
+int labpc_common_attach(struct comedi_device *dev,
+                       unsigned int irq, unsigned long isr_flags)
+{
+       const struct labpc_boardinfo *board = comedi_board(dev);
+       struct labpc_private *devpriv = dev->private;
+       struct comedi_subdevice *s;
+       int ret;
+       int i;
+
+       if (dev->mmio) {
+               devpriv->read_byte = labpc_readb;
+               devpriv->write_byte = labpc_writeb;
+       } else {
+               devpriv->read_byte = labpc_inb;
+               devpriv->write_byte = labpc_outb;
+       }
+
+       /* initialize board's command registers */
+       devpriv->write_byte(dev, devpriv->cmd1, CMD1_REG);
+       devpriv->write_byte(dev, devpriv->cmd2, CMD2_REG);
+       devpriv->write_byte(dev, devpriv->cmd3, CMD3_REG);
+       devpriv->write_byte(dev, devpriv->cmd4, CMD4_REG);
+       if (board->is_labpc1200) {
+               devpriv->write_byte(dev, devpriv->cmd5, CMD5_REG);
+               devpriv->write_byte(dev, devpriv->cmd6, CMD6_REG);
+       }
+
+       if (irq) {
+               ret = request_irq(irq, labpc_interrupt, isr_flags,
+                                 dev->board_name, dev);
+               if (ret == 0)
+                       dev->irq = irq;
+       }
+
+       ret = comedi_alloc_subdevices(dev, 5);
+       if (ret)
+               return ret;
+
+       /* analog input subdevice */
+       s = &dev->subdevices[0];
+       s->type         = COMEDI_SUBD_AI;
+       s->subdev_flags = SDF_READABLE | SDF_GROUND | SDF_COMMON | SDF_DIFF;
+       s->n_chan       = 8;
+       s->len_chanlist = 8;
+       s->maxdata      = 0x0fff;
+       s->range_table  = board->is_labpc1200 ?
+                         &range_labpc_1200_ai : &range_labpc_plus_ai;
+       s->insn_read    = labpc_ai_insn_read;
+       if (dev->irq) {
+               dev->read_subdev = s;
+               s->subdev_flags |= SDF_CMD_READ;
+               s->do_cmd       = labpc_ai_cmd;
+               s->do_cmdtest   = labpc_ai_cmdtest;
+               s->cancel       = labpc_cancel;
+       }
+
+       /* analog output */
+       s = &dev->subdevices[1];
+       if (board->has_ao) {
+               s->type         = COMEDI_SUBD_AO;
+               s->subdev_flags = SDF_READABLE | SDF_WRITABLE | SDF_GROUND;
+               s->n_chan       = NUM_AO_CHAN;
+               s->maxdata      = 0x0fff;
+               s->range_table  = &range_labpc_ao;
+               s->insn_read    = labpc_ao_insn_read;
+               s->insn_write   = labpc_ao_insn_write;
+
+               /* initialize analog outputs to a known value */
+               for (i = 0; i < s->n_chan; i++) {
+                       short lsb, msb;
+
+                       devpriv->ao_value[i] = s->maxdata / 2;
+                       lsb = devpriv->ao_value[i] & 0xff;
+                       msb = (devpriv->ao_value[i] >> 8) & 0xff;
+                       devpriv->write_byte(dev, lsb, DAC_LSB_REG(i));
+                       devpriv->write_byte(dev, msb, DAC_MSB_REG(i));
+               }
+       } else {
+               s->type         = COMEDI_SUBD_UNUSED;
+       }
+
+       /* 8255 dio */
+       s = &dev->subdevices[2];
+       if (dev->mmio)
+               ret = subdev_8255_mm_init(dev, s, NULL, DIO_BASE_REG);
+       else
+               ret = subdev_8255_init(dev, s, NULL, DIO_BASE_REG);
+       if (ret)
+               return ret;
+
+       /*  calibration subdevices for boards that have one */
+       s = &dev->subdevices[3];
+       if (board->is_labpc1200) {
+               s->type         = COMEDI_SUBD_CALIB;
+               s->subdev_flags = SDF_READABLE | SDF_WRITABLE | SDF_INTERNAL;
+               s->n_chan       = 16;
+               s->maxdata      = 0xff;
+               s->insn_read    = labpc_calib_insn_read;
+               s->insn_write   = labpc_calib_insn_write;
+
+               for (i = 0; i < s->n_chan; i++)
+                       write_caldac(dev, i, s->maxdata / 2);
+       } else {
+               s->type         = COMEDI_SUBD_UNUSED;
+       }
+
+       /* EEPROM */
+       s = &dev->subdevices[4];
+       if (board->is_labpc1200) {
+               s->type         = COMEDI_SUBD_MEMORY;
+               s->subdev_flags = SDF_READABLE | SDF_WRITABLE | SDF_INTERNAL;
+               s->n_chan       = EEPROM_SIZE;
+               s->maxdata      = 0xff;
+               s->insn_read    = labpc_eeprom_insn_read;
+               s->insn_write   = labpc_eeprom_insn_write;
+
+               for (i = 0; i < s->n_chan; i++)
+                       devpriv->eeprom_data[i] = labpc_eeprom_read(dev, i);
+       } else {
+               s->type         = COMEDI_SUBD_UNUSED;
+       }
+
+       return 0;
+}
+EXPORT_SYMBOL_GPL(labpc_common_attach);
+
+static int __init labpc_common_init(void)
+{
+       return 0;
+}
+module_init(labpc_common_init);
+
+static void __exit labpc_common_exit(void)
+{
+}
+module_exit(labpc_common_exit);
+
+MODULE_AUTHOR("Comedi http://www.comedi.org");
+MODULE_DESCRIPTION("Comedi helper for ni_labpc, ni_labpc_pci, ni_labpc_cs");
+MODULE_LICENSE("GPL");