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Commit a351ecf3 authored by Bill Pemberton's avatar Bill Pemberton Committed by Greg Kroah-Hartman
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Staging: comedi: remove C99 comments in das1800.c 

Signed-off-by: default avatarBill Pemberton <wfp5p@virginia.edu>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent cf0fd108
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Showing with 102 additions and 102 deletions
drivers/staging/comedi/drivers/das1800.c
View file @ a351ecf3
......@@ -108,12 +108,12 @@ Unipolar and bipolar ranges cannot be mixed in the channel/gain list.
#include "8253.h"
#include "comedi_fc.h"
// misc. defines
#define DAS1800_SIZE 16 //uses 16 io addresses
#define FIFO_SIZE 1024 // 1024 sample fifo
#define TIMER_BASE 200 // 5 Mhz master clock
#define UNIPOLAR 0x4 // bit that determines whether input range is uni/bipolar
#define DMA_BUF_SIZE 0x1ff00 // size in bytes of dma buffers
/* misc. defines */
#define DAS1800_SIZE 16 /* uses 16 io addresses */
#define FIFO_SIZE 1024 /* 1024 sample fifo */
#define TIMER_BASE 200 /* 5 Mhz master clock */
#define UNIPOLAR 0x4 /* bit that determines whether input range is uni/bipolar */
#define DMA_BUF_SIZE 0x1ff00 /* size in bytes of dma buffers */
/* Registers for the das1800 */
#define DAS1800_FIFO 0x0
......@@ -138,7 +138,7 @@ Unipolar and bipolar ranges cannot be mixed in the channel/gain list.
#define DMA_CH5_CH6 0x5
#define DMA_CH6_CH7 0x6
#define DMA_CH7_CH5 0x7
#define DMA_ENABLED 0x3 //mask used to determine if dma is enabled
#define DMA_ENABLED 0x3 /* mask used to determine if dma is enabled */
#define DMA_DUAL 0x4
#define IRQ3 0x8
#define IRQ5 0x10
......@@ -156,7 +156,7 @@ Unipolar and bipolar ranges cannot be mixed in the channel/gain list.
#define SD 0x40
#define UB 0x80
#define DAS1800_STATUS 0x7
// bits that prevent interrupt status bits (and CVEN) from being cleared on write
/* bits that prevent interrupt status bits (and CVEN) from being cleared on write */
#define CLEAR_INTR_MASK (CVEN_MASK | 0x1f)
#define INT 0x1
#define DMATC 0x2
......@@ -164,14 +164,14 @@ Unipolar and bipolar ranges cannot be mixed in the channel/gain list.
#define OVF 0x10
#define FHF 0x20
#define FNE 0x40
#define CVEN_MASK 0x40 // masks CVEN on write
#define CVEN_MASK 0x40 /* masks CVEN on write */
#define CVEN 0x80
#define DAS1800_BURST_LENGTH 0x8
#define DAS1800_BURST_RATE 0x9
#define DAS1800_QRAM_ADDRESS 0xa
#define DAS1800_COUNTER 0xc
#define IOBASE2 0x400 //offset of additional ioports used on 'ao' cards
#define IOBASE2 0x400 /* offset of additional ioports used on 'ao' cards */
enum {
das1701st, das1701st_da, das1702st, das1702st_da, das1702hr,
......@@ -212,7 +212,7 @@ static int das1800_set_frequency(struct comedi_device * dev);
static unsigned int burst_convert_arg(unsigned int convert_arg, int round_mode);
static unsigned int suggest_transfer_size(struct comedi_cmd * cmd);
// analog input ranges
/* analog input ranges */
static const struct comedi_lrange range_ai_das1801 = {
8,
{
......@@ -485,7 +485,7 @@ struct das1800_private {
#define devpriv ((struct das1800_private *)dev->private)
// analog out range for boards with basic analog out
/* analog out range for boards with basic analog out */
static const struct comedi_lrange range_ao_1 = {
1,
{
......@@ -493,7 +493,7 @@ static const struct comedi_lrange range_ao_1 = {
}
};
// analog out range for 'ao' boards
/* analog out range for 'ao' boards */
/*
static const struct comedi_lrange range_ao_2 = {
2,
......@@ -525,26 +525,26 @@ static int das1800_init_dma(struct comedi_device * dev, unsigned int dma0,
{
unsigned long flags;
// need an irq to do dma
/* need an irq to do dma */
if (dev->irq && dma0) {
//encode dma0 and dma1 into 2 digit hexadecimal for switch
/* encode dma0 and dma1 into 2 digit hexadecimal for switch */
switch ((dma0 & 0x7) | (dma1 << 4)) {
case 0x5: // dma0 == 5
case 0x5: /* dma0 == 5 */
devpriv->dma_bits |= DMA_CH5;
break;
case 0x6: // dma0 == 6
case 0x6: /* dma0 == 6 */
devpriv->dma_bits |= DMA_CH6;
break;
case 0x7: // dma0 == 7
case 0x7: /* dma0 == 7 */
devpriv->dma_bits |= DMA_CH7;
break;
case 0x65: // dma0 == 5, dma1 == 6
case 0x65: /* dma0 == 5, dma1 == 6 */
devpriv->dma_bits |= DMA_CH5_CH6;
break;
case 0x76: // dma0 == 6, dma1 == 7
case 0x76: /* dma0 == 6, dma1 == 7 */
devpriv->dma_bits |= DMA_CH6_CH7;
break;
case 0x57: // dma0 == 7, dma1 == 5
case 0x57: /* dma0 == 7, dma1 == 5 */
devpriv->dma_bits |= DMA_CH7_CH5;
break;
default:
......@@ -638,7 +638,7 @@ static int das1800_attach(struct comedi_device * dev, struct comedi_devconfig *
dev->board_ptr = das1800_boards + board;
dev->board_name = thisboard->name;
// if it is an 'ao' board with fancy analog out then we need extra io ports
/* if it is an 'ao' board with fancy analog out then we need extra io ports */
if (thisboard->ao_ability == 2) {
iobase2 = iobase + IOBASE2;
if (!request_region(iobase2, DAS1800_SIZE,
......@@ -659,7 +659,7 @@ static int das1800_attach(struct comedi_device * dev, struct comedi_devconfig *
}
dev->irq = irq;
// set bits that tell card which irq to use
/* set bits that tell card which irq to use */
switch (irq) {
case 0:
break;
......@@ -751,12 +751,12 @@ static int das1800_attach(struct comedi_device * dev, struct comedi_devconfig *
das1800_cancel(dev, dev->read_subdev);
// initialize digital out channels
/* initialize digital out channels */
outb(devpriv->do_bits, dev->iobase + DAS1800_DIGITAL);
// initialize analog out channels
/* initialize analog out channels */
if (thisboard->ao_ability == 1) {
// select 'update' dac channel for baseAddress + 0x0
/* select 'update' dac channel for baseAddress + 0x0 */
outb(DAC(thisboard->ao_n_chan - 1),
dev->iobase + DAS1800_SELECT);
outw(devpriv->ao_update_bits, dev->iobase + DAS1800_DAC);
......@@ -871,7 +871,7 @@ static int das1800_ai_poll(struct comedi_device * dev, struct comedi_subdevice *
{
unsigned long flags;
// prevent race with interrupt handler
/* prevent race with interrupt handler */
comedi_spin_lock_irqsave(&dev->spinlock, flags);
das1800_ai_handler(dev);
comedi_spin_unlock_irqrestore(&dev->spinlock, flags);
......@@ -901,14 +901,14 @@ static irqreturn_t das1800_interrupt(int irq, void *d PT_REGS_ARG)
}
/* clear the interrupt status bit INT */
outb(CLEAR_INTR_MASK & ~INT, dev->iobase + DAS1800_STATUS);
// handle interrupt
/* handle interrupt */
das1800_ai_handler(dev);
spin_unlock(&dev->spinlock);
return IRQ_HANDLED;
}
// the guts of the interrupt handler, that is shared with das1800_ai_poll
/* the guts of the interrupt handler, that is shared with das1800_ai_poll */
static void das1800_ai_handler(struct comedi_device * dev)
{
struct comedi_subdevice *s = dev->subdevices + 0; /* analog input subdevice */
......@@ -917,22 +917,22 @@ static void das1800_ai_handler(struct comedi_device * dev)
unsigned int status = inb(dev->iobase + DAS1800_STATUS);
async->events = 0;
// select adc for base address + 0
/* select adc for base address + 0 */
outb(ADC, dev->iobase + DAS1800_SELECT);
// dma buffer full
/* dma buffer full */
if (devpriv->irq_dma_bits & DMA_ENABLED) {
// look for data from dma transfer even if dma terminal count hasn't happened yet
/* look for data from dma transfer even if dma terminal count hasn't happened yet */
das1800_handle_dma(dev, s, status);
} else if (status & FHF) { // if fifo half full
} else if (status & FHF) { /* if fifo half full */
das1800_handle_fifo_half_full(dev, s);
} else if (status & FNE) { // if fifo not empty
} else if (status & FNE) { /* if fifo not empty */
das1800_handle_fifo_not_empty(dev, s);
}
async->events |= COMEDI_CB_BLOCK;
/* if the card's fifo has overflowed */
if (status & OVF) {
// clear OVF interrupt bit
/* clear OVF interrupt bit */
outb(CLEAR_INTR_MASK & ~OVF, dev->iobase + DAS1800_STATUS);
comedi_error(dev, "DAS1800 FIFO overflow");
das1800_cancel(dev, s);
......@@ -940,19 +940,19 @@ static void das1800_ai_handler(struct comedi_device * dev)
comedi_event(dev, s);
return;
}
// stop taking data if appropriate
/* stop taking data if appropriate */
/* stop_src TRIG_EXT */
if (status & CT0TC) {
// clear CT0TC interrupt bit
/* clear CT0TC interrupt bit */
outb(CLEAR_INTR_MASK & ~CT0TC, dev->iobase + DAS1800_STATUS);
// make sure we get all remaining data from board before quitting
/* make sure we get all remaining data from board before quitting */
if (devpriv->irq_dma_bits & DMA_ENABLED)
das1800_flush_dma(dev, s);
else
das1800_handle_fifo_not_empty(dev, s);
das1800_cancel(dev, s); /* disable hardware conversions */
async->events |= COMEDI_CB_EOA;
} else if (cmd->stop_src == TRIG_COUNT && devpriv->count == 0) { // stop_src TRIG_COUNT
} else if (cmd->stop_src == TRIG_COUNT && devpriv->count == 0) { /* stop_src TRIG_COUNT */
das1800_cancel(dev, s); /* disable hardware conversions */
async->events |= COMEDI_CB_EOA;
}
......@@ -971,7 +971,7 @@ static void das1800_handle_dma(struct comedi_device * dev, struct comedi_subdevi
flags = claim_dma_lock();
das1800_flush_dma_channel(dev, s, devpriv->dma_current,
devpriv->dma_current_buf);
// re-enable dma channel
/* re-enable dma channel */
set_dma_addr(devpriv->dma_current,
virt_to_bus(devpriv->dma_current_buf));
set_dma_count(devpriv->dma_current, devpriv->dma_transfer_size);
......@@ -979,11 +979,11 @@ static void das1800_handle_dma(struct comedi_device * dev, struct comedi_subdevi
release_dma_lock(flags);
if (status & DMATC) {
// clear DMATC interrupt bit
/* clear DMATC interrupt bit */
outb(CLEAR_INTR_MASK & ~DMATC, dev->iobase + DAS1800_STATUS);
// switch dma channels for next time, if appropriate
/* switch dma channels for next time, if appropriate */
if (dual_dma) {
// read data from the other channel next time
/* read data from the other channel next time */
if (devpriv->dma_current == devpriv->dma0) {
devpriv->dma_current = devpriv->dma1;
devpriv->dma_current_buf = devpriv->ai_buf1;
......@@ -1035,7 +1035,7 @@ static void das1800_flush_dma_channel(struct comedi_device * dev, struct comedi_
* get set correctly */
clear_dma_ff(channel);
// figure out how many points to read
/* figure out how many points to read */
num_bytes = devpriv->dma_transfer_size - get_dma_residue(channel);
num_samples = num_bytes / sizeof(short);
......@@ -1063,7 +1063,7 @@ static void das1800_flush_dma(struct comedi_device * dev, struct comedi_subdevic
devpriv->dma_current_buf);
if (dual_dma) {
// switch to other channel and flush it
/* switch to other channel and flush it */
if (devpriv->dma_current == devpriv->dma0) {
devpriv->dma_current = devpriv->dma1;
devpriv->dma_current_buf = devpriv->ai_buf1;
......@@ -1077,7 +1077,7 @@ static void das1800_flush_dma(struct comedi_device * dev, struct comedi_subdevic
release_dma_lock(flags);
// get any remaining samples in fifo
/* get any remaining samples in fifo */
das1800_handle_fifo_not_empty(dev, s);
return;
......@@ -1180,7 +1180,7 @@ static int das1800_ai_do_cmdtest(struct comedi_device * dev, struct comedi_subde
/* step 2: make sure trigger sources are unique and mutually compatible */
// uniqueness check
/* uniqueness check */
if (cmd->start_src != TRIG_NOW && cmd->start_src != TRIG_EXT)
err++;
if (cmd->scan_begin_src != TRIG_FOLLOW &&
......@@ -1192,7 +1192,7 @@ static int das1800_ai_do_cmdtest(struct comedi_device * dev, struct comedi_subde
if (cmd->stop_src != TRIG_COUNT &&
cmd->stop_src != TRIG_NONE && cmd->stop_src != TRIG_EXT)
err++;
//compatibility check
/* compatibility check */
if (cmd->scan_begin_src != TRIG_FOLLOW &&
cmd->convert_src != TRIG_TIMER)
err++;
......@@ -1244,7 +1244,7 @@ static int das1800_ai_do_cmdtest(struct comedi_device * dev, struct comedi_subde
/* step 4: fix up any arguments */
if (cmd->convert_src == TRIG_TIMER) {
// if we are not in burst mode
/* if we are not in burst mode */
if (cmd->scan_begin_src == TRIG_FOLLOW) {
tmp_arg = cmd->convert_arg;
/* calculate counter values that give desired timing */
......@@ -1255,9 +1255,9 @@ static int das1800_ai_do_cmdtest(struct comedi_device * dev, struct comedi_subde
if (tmp_arg != cmd->convert_arg)
err++;
}
// if we are in burst mode
/* if we are in burst mode */
else {
// check that convert_arg is compatible
/* check that convert_arg is compatible */
tmp_arg = cmd->convert_arg;
cmd->convert_arg =
burst_convert_arg(cmd->convert_arg,
......@@ -1266,7 +1266,7 @@ static int das1800_ai_do_cmdtest(struct comedi_device * dev, struct comedi_subde
err++;
if (cmd->scan_begin_src == TRIG_TIMER) {
// if scans are timed faster than conversion rate allows
/* if scans are timed faster than conversion rate allows */
if (cmd->convert_arg * cmd->chanlist_len >
cmd->scan_begin_arg) {
cmd->scan_begin_arg =
......@@ -1290,7 +1290,7 @@ static int das1800_ai_do_cmdtest(struct comedi_device * dev, struct comedi_subde
if (err)
return 4;
// make sure user is not trying to mix unipolar and bipolar ranges
/* make sure user is not trying to mix unipolar and bipolar ranges */
if (cmd->chanlist) {
unipolar = CR_RANGE(cmd->chanlist[0]) & UNIPOLAR;
for (i = 1; i < cmd->chanlist_len; i++) {
......@@ -1311,14 +1311,14 @@ static int das1800_ai_do_cmdtest(struct comedi_device * dev, struct comedi_subde
/* analog input cmd interface */
// first, some utility functions used in the main ai_do_cmd()
/* first, some utility functions used in the main ai_do_cmd() */
// returns appropriate bits for control register a, depending on command
/* returns appropriate bits for control register a, depending on command */
static int control_a_bits(struct comedi_cmd cmd)
{
int control_a;
control_a = FFEN; //enable fifo
control_a = FFEN; /* enable fifo */
if (cmd.stop_src == TRIG_EXT) {
control_a |= ATEN;
}
......@@ -1336,7 +1336,7 @@ static int control_a_bits(struct comedi_cmd cmd)
return control_a;
}
// returns appropriate bits for control register c, depending on command
/* returns appropriate bits for control register c, depending on command */
static int control_c_bits(struct comedi_cmd cmd)
{
int control_c;
......@@ -1346,7 +1346,7 @@ static int control_c_bits(struct comedi_cmd cmd)
* select unipolar / bipolar
*/
aref = CR_AREF(cmd.chanlist[0]);
control_c = UQEN; //enable upper qram addresses
control_c = UQEN; /* enable upper qram addresses */
if (aref != AREF_DIFF)
control_c |= SD;
if (aref == AREF_COMMON)
......@@ -1355,7 +1355,7 @@ static int control_c_bits(struct comedi_cmd cmd)
if (CR_RANGE(cmd.chanlist[0]) & UNIPOLAR)
control_c |= UB;
switch (cmd.scan_begin_src) {
case TRIG_FOLLOW: // not in burst mode
case TRIG_FOLLOW: /* not in burst mode */
switch (cmd.convert_src) {
case TRIG_TIMER:
/* trig on cascaded counters */
......@@ -1370,11 +1370,11 @@ static int control_c_bits(struct comedi_cmd cmd)
}
break;
case TRIG_TIMER:
// burst mode with internal pacer clock
/* burst mode with internal pacer clock */
control_c |= BMDE | IPCLK;
break;
case TRIG_EXT:
// burst mode with external trigger
/* burst mode with external trigger */
control_c |= BMDE | XPCLK;
break;
default:
......@@ -1384,12 +1384,12 @@ static int control_c_bits(struct comedi_cmd cmd)
return control_c;
}
// sets up counters
/* sets up counters */
static int setup_counters(struct comedi_device * dev, struct comedi_cmd cmd)
{
// setup cascaded counters for conversion/scan frequency
/* setup cascaded counters for conversion/scan frequency */
switch (cmd.scan_begin_src) {
case TRIG_FOLLOW: // not in burst mode
case TRIG_FOLLOW: /* not in burst mode */
if (cmd.convert_src == TRIG_TIMER) {
/* set conversion frequency */
i8253_cascade_ns_to_timer_2div(TIMER_BASE,
......@@ -1401,7 +1401,7 @@ static int setup_counters(struct comedi_device * dev, struct comedi_cmd cmd)
}
}
break;
case TRIG_TIMER: // in burst mode
case TRIG_TIMER: /* in burst mode */
/* set scan frequency */
i8253_cascade_ns_to_timer_2div(TIMER_BASE, &(devpriv->divisor1),
&(devpriv->divisor2), &(cmd.scan_begin_arg),
......@@ -1414,16 +1414,16 @@ static int setup_counters(struct comedi_device * dev, struct comedi_cmd cmd)
break;
}
// setup counter 0 for 'about triggering'
/* setup counter 0 for 'about triggering' */
if (cmd.stop_src == TRIG_EXT) {
// load counter 0 in mode 0
/* load counter 0 in mode 0 */
i8254_load(dev->iobase + DAS1800_COUNTER, 0, 0, 1, 0);
}
return 0;
}
// sets up dma
/* sets up dma */
static void setup_dma(struct comedi_device * dev, struct comedi_cmd cmd)
{
unsigned long lock_flags;
......@@ -1440,19 +1440,19 @@ static void setup_dma(struct comedi_device * dev, struct comedi_cmd cmd)
* count and address get set correctly */
clear_dma_ff(devpriv->dma0);
set_dma_addr(devpriv->dma0, virt_to_bus(devpriv->ai_buf0));
// set appropriate size of transfer
/* set appropriate size of transfer */
set_dma_count(devpriv->dma0, devpriv->dma_transfer_size);
devpriv->dma_current = devpriv->dma0;
devpriv->dma_current_buf = devpriv->ai_buf0;
enable_dma(devpriv->dma0);
// set up dual dma if appropriate
/* set up dual dma if appropriate */
if (dual_dma) {
disable_dma(devpriv->dma1);
/* clear flip-flop to make sure 2-byte registers for
* count and address get set correctly */
clear_dma_ff(devpriv->dma1);
set_dma_addr(devpriv->dma1, virt_to_bus(devpriv->ai_buf1));
// set appropriate size of transfer
/* set appropriate size of transfer */
set_dma_count(devpriv->dma1, devpriv->dma_transfer_size);
enable_dma(devpriv->dma1);
}
......@@ -1461,16 +1461,16 @@ static void setup_dma(struct comedi_device * dev, struct comedi_cmd cmd)
return;
}
// programs channel/gain list into card
/* programs channel/gain list into card */
static void program_chanlist(struct comedi_device * dev, struct comedi_cmd cmd)
{
int i, n, chan_range;
unsigned long irq_flags;
const int range_mask = 0x3; //masks unipolar/bipolar bit off range
const int range_mask = 0x3; /* masks unipolar/bipolar bit off range */
const int range_bitshift = 8;
n = cmd.chanlist_len;
// spinlock protects indirect addressing
/* spinlock protects indirect addressing */
comedi_spin_lock_irqsave(&dev->spinlock, irq_flags);
outb(QRAM, dev->iobase + DAS1800_SELECT); /* select QRAM for baseAddress + 0x0 */
outb(n - 1, dev->iobase + DAS1800_QRAM_ADDRESS); /*set QRAM address start */
......@@ -1488,7 +1488,7 @@ static void program_chanlist(struct comedi_device * dev, struct comedi_cmd cmd)
return;
}
// analog input do_cmd
/* analog input do_cmd */
static int das1800_ai_do_cmd(struct comedi_device * dev, struct comedi_subdevice * s)
{
int ret;
......@@ -1509,22 +1509,22 @@ static int das1800_ai_do_cmd(struct comedi_device * dev, struct comedi_subdevice
} else {
devpriv->irq_dma_bits |= devpriv->dma_bits;
}
// interrupt on end of conversion for TRIG_WAKE_EOS
/* interrupt on end of conversion for TRIG_WAKE_EOS */
if (cmd.flags & TRIG_WAKE_EOS) {
// interrupt fifo not empty
/* interrupt fifo not empty */
devpriv->irq_dma_bits &= ~FIMD;
} else {
// interrupt fifo half full
/* interrupt fifo half full */
devpriv->irq_dma_bits |= FIMD;
}
// determine how many conversions we need
/* determine how many conversions we need */
if (cmd.stop_src == TRIG_COUNT) {
devpriv->count = cmd.stop_arg * cmd.chanlist_len;
}
das1800_cancel(dev, s);
// determine proper bits for control registers
/* determine proper bits for control registers */
control_a = control_a_bits(cmd);
control_c = control_c_bits(cmd);
......@@ -1537,14 +1537,14 @@ static int das1800_ai_do_cmd(struct comedi_device * dev, struct comedi_subdevice
}
setup_dma(dev, cmd);
outb(control_c, dev->iobase + DAS1800_CONTROL_C);
// set conversion rate and length for burst mode
/* set conversion rate and length for burst mode */
if (control_c & BMDE) {
// program conversion period with number of microseconds minus 1
/* program conversion period with number of microseconds minus 1 */
outb(cmd.convert_arg / 1000 - 1,
dev->iobase + DAS1800_BURST_RATE);
outb(cmd.chanlist_len - 1, dev->iobase + DAS1800_BURST_LENGTH);
}
outb(devpriv->irq_dma_bits, dev->iobase + DAS1800_CONTROL_B); // enable irq/dma
outb(devpriv->irq_dma_bits, dev->iobase + DAS1800_CONTROL_B); /* enable irq/dma */
outb(control_a, dev->iobase + DAS1800_CONTROL_A); /* enable fifo and triggering */
outb(CVEN, dev->iobase + DAS1800_STATUS); /* enable conversions */
......@@ -1616,21 +1616,21 @@ static int das1800_ao_winsn(struct comedi_device * dev, struct comedi_subdevice
struct comedi_insn * insn, unsigned int * data)
{
int chan = CR_CHAN(insn->chanspec);
// int range = CR_RANGE(insn->chanspec);
/* int range = CR_RANGE(insn->chanspec); */
int update_chan = thisboard->ao_n_chan - 1;
short output;
unsigned long irq_flags;
// card expects two's complement data
/* card expects two's complement data */
output = data[0] - (1 << (thisboard->resolution - 1));
// if the write is to the 'update' channel, we need to remember its value
/* if the write is to the 'update' channel, we need to remember its value */
if (chan == update_chan)
devpriv->ao_update_bits = output;
// write to channel
/* write to channel */
comedi_spin_lock_irqsave(&dev->spinlock, irq_flags);
outb(DAC(chan), dev->iobase + DAS1800_SELECT); /* select dac channel for baseAddress + 0x0 */
outw(output, dev->iobase + DAS1800_DAC);
// now we need to write to 'update' channel to update all dac channels
/* now we need to write to 'update' channel to update all dac channels */
if (chan != update_chan) {
outb(DAC(update_chan), dev->iobase + DAS1800_SELECT); /* select 'update' channel for baseAddress + 0x0 */
outw(devpriv->ao_update_bits, dev->iobase + DAS1800_DAC);
......@@ -1657,7 +1657,7 @@ static int das1800_do_wbits(struct comedi_device * dev, struct comedi_subdevice
{
unsigned int wbits;
// only set bits that have been masked
/* only set bits that have been masked */
data[0] &= (1 << s->n_chan) - 1;
wbits = devpriv->do_bits;
wbits &= ~data[0];
......@@ -1676,11 +1676,11 @@ static int das1800_set_frequency(struct comedi_device * dev)
{
int err = 0;
// counter 1, mode 2
/* counter 1, mode 2 */
if (i8254_load(dev->iobase + DAS1800_COUNTER, 0, 1, devpriv->divisor1,
2))
err++;
// counter 2, mode 2
/* counter 2, mode 2 */
if (i8254_load(dev->iobase + DAS1800_COUNTER, 0, 2, devpriv->divisor2,
2))
err++;
......@@ -1697,11 +1697,11 @@ static unsigned int burst_convert_arg(unsigned int convert_arg, int round_mode)
{
unsigned int micro_sec;
// in burst mode, the maximum conversion time is 64 microseconds
/* in burst mode, the maximum conversion time is 64 microseconds */
if (convert_arg > 64000)
convert_arg = 64000;
// the conversion time must be an integral number of microseconds
/* the conversion time must be an integral number of microseconds */
switch (round_mode) {
case TRIG_ROUND_NEAREST:
default:
......@@ -1715,21 +1715,21 @@ static unsigned int burst_convert_arg(unsigned int convert_arg, int round_mode)
break;
}
// return number of nanoseconds
/* return number of nanoseconds */
return micro_sec * 1000;
}
// utility function that suggests a dma transfer size based on the conversion period 'ns'
/* utility function that suggests a dma transfer size based on the conversion period 'ns' */
static unsigned int suggest_transfer_size(struct comedi_cmd * cmd)
{
unsigned int size = DMA_BUF_SIZE;
static const int sample_size = 2; // size in bytes of one sample from board
unsigned int fill_time = 300000000; // target time in nanoseconds for filling dma buffer
unsigned int max_size; // maximum size we will allow for a transfer
static const int sample_size = 2; /* size in bytes of one sample from board */
unsigned int fill_time = 300000000; /* target time in nanoseconds for filling dma buffer */
unsigned int max_size; /* maximum size we will allow for a transfer */
// make dma buffer fill in 0.3 seconds for timed modes
/* make dma buffer fill in 0.3 seconds for timed modes */
switch (cmd->scan_begin_src) {
case TRIG_FOLLOW: // not in burst mode
case TRIG_FOLLOW: /* not in burst mode */
if (cmd->convert_src == TRIG_TIMER)
size = (fill_time / cmd->convert_arg) * sample_size;
break;
......@@ -1742,9 +1742,9 @@ static unsigned int suggest_transfer_size(struct comedi_cmd * cmd)
break;
}
// set a minimum and maximum size allowed
/* set a minimum and maximum size allowed */
max_size = DMA_BUF_SIZE;
// if we are taking limited number of conversions, limit transfer size to that
/* if we are taking limited number of conversions, limit transfer size to that */
if (cmd->stop_src == TRIG_COUNT &&
cmd->stop_arg * cmd->chanlist_len * sample_size < max_size)
max_size = cmd->stop_arg * cmd->chanlist_len * sample_size;
......
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