/*
- comedi/drivers/comedi_test.c
+ * comedi/drivers/comedi_test.c
+ *
+ * Generates fake waveform signals that can be read through
+ * the command interface. It does _not_ read from any board;
+ * it just generates deterministic waveforms.
+ * Useful for various testing purposes.
+ *
+ * Copyright (C) 2002 Joachim Wuttke <Joachim.Wuttke@icn.siemens.de>
+ * Copyright (C) 2002 Frank Mori Hess <fmhess@users.sourceforge.net>
+ *
+ * COMEDI - Linux Control and Measurement Device Interface
+ * Copyright (C) 2000 David A. Schleef <ds@schleef.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
- Generates fake waveform signals that can be read through
- the command interface. It does _not_ read from any board;
- it just generates deterministic waveforms.
- Useful for various testing purposes.
-
- Copyright (C) 2002 Joachim Wuttke <Joachim.Wuttke@icn.siemens.de>
- Copyright (C) 2002 Frank Mori Hess <fmhess@users.sourceforge.net>
-
- COMEDI - Linux Control and Measurement Device Interface
- Copyright (C) 2000 David A. Schleef <ds@schleef.org>
-
- This program is free software; you can redistribute it and/or modify
- it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 2 of the License, or
- (at your option) any later version.
-
- This program is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- GNU General Public License for more details.
-*/
/*
-Driver: comedi_test
-Description: generates fake waveforms
-Author: Joachim Wuttke <Joachim.Wuttke@icn.siemens.de>, Frank Mori Hess
- <fmhess@users.sourceforge.net>, ds
-Devices:
-Status: works
-Updated: Sat, 16 Mar 2002 17:34:48 -0800
-
-This driver is mainly for testing purposes, but can also be used to
-generate sample waveforms on systems that don't have data acquisition
-hardware.
-
-Configuration options:
- [0] - Amplitude in microvolts for fake waveforms (default 1 volt)
- [1] - Period in microseconds for fake waveforms (default 0.1 sec)
-
-Generates a sawtooth wave on channel 0, square wave on channel 1, additional
-waveforms could be added to other channels (currently they return flatline
-zero volts).
-
-*/
+ * Driver: comedi_test
+ * Description: generates fake waveforms
+ * Author: Joachim Wuttke <Joachim.Wuttke@icn.siemens.de>, Frank Mori Hess
+ * <fmhess@users.sourceforge.net>, ds
+ * Devices:
+ * Status: works
+ * Updated: Sat, 16 Mar 2002 17:34:48 -0800
+ *
+ * This driver is mainly for testing purposes, but can also be used to
+ * generate sample waveforms on systems that don't have data acquisition
+ * hardware.
+ *
+ * Configuration options:
+ * [0] - Amplitude in microvolts for fake waveforms (default 1 volt)
+ * [1] - Period in microseconds for fake waveforms (default 0.1 sec)
+ *
+ * Generates a sawtooth wave on channel 0, square wave on channel 1, additional
+ * waveforms could be added to other channels (currently they return flatline
+ * zero volts).
+ */
#include <linux/module.h>
#include "../comedidev.h"
struct timer_list timer;
ktime_t last; /* time last timer interrupt occurred */
unsigned int uvolt_amplitude; /* waveform amplitude in microvolts */
- unsigned long usec_period; /* waveform period in microseconds */
- unsigned long usec_current; /* current time (mod waveform period) */
+ unsigned int usec_period; /* waveform period in microseconds */
+ unsigned int usec_current; /* current time (mod waveform period) */
unsigned long usec_remainder; /* usec since last scan */
unsigned long state_bits;
unsigned int scan_period; /* scan period in usec */
unsigned int ao_loopbacks[N_CHANS];
};
-/* 1000 nanosec in a microsec */
-static const int nano_per_micro = 1000;
-
/* fake analog input ranges */
static const struct comedi_lrange waveform_ai_ranges = {
2, {
static unsigned short fake_sawtooth(struct comedi_device *dev,
unsigned int range_index,
- unsigned long current_time)
+ unsigned int current_time)
{
struct waveform_private *devpriv = dev->private;
struct comedi_subdevice *s = dev->read_subdev;
binary_amplitude *= devpriv->uvolt_amplitude;
do_div(binary_amplitude, krange->max - krange->min);
- current_time %= devpriv->usec_period;
value = current_time;
value *= binary_amplitude * 2;
do_div(value, devpriv->usec_period);
- value -= binary_amplitude; /* get rid of sawtooth's dc offset */
+ value += offset;
+ /* get rid of sawtooth's dc offset and clamp value */
+ if (value < binary_amplitude) {
+ value = 0; /* negative saturation */
+ } else {
+ value -= binary_amplitude;
+ if (value > s->maxdata)
+ value = s->maxdata; /* positive saturation */
+ }
- return offset + value;
+ return value;
}
static unsigned short fake_squarewave(struct comedi_device *dev,
unsigned int range_index,
- unsigned long current_time)
+ unsigned int current_time)
{
struct waveform_private *devpriv = dev->private;
struct comedi_subdevice *s = dev->read_subdev;
u64 value;
const struct comedi_krange *krange =
&s->range_table->range[range_index];
- current_time %= devpriv->usec_period;
value = s->maxdata;
value *= devpriv->uvolt_amplitude;
do_div(value, krange->max - krange->min);
- if (current_time < devpriv->usec_period / 2)
- value *= -1;
+ /* get one of two values for square-wave and clamp */
+ if (current_time < devpriv->usec_period / 2) {
+ if (offset < value)
+ value = 0; /* negative saturation */
+ else
+ value = offset - value;
+ } else {
+ value += offset;
+ if (value > s->maxdata)
+ value = s->maxdata; /* positive saturation */
+ }
- return offset + value;
+ return value;
}
static unsigned short fake_flatline(struct comedi_device *dev,
unsigned int range_index,
- unsigned long current_time)
+ unsigned int current_time)
{
return dev->read_subdev->maxdata / 2;
}
/* generates a different waveform depending on what channel is read */
static unsigned short fake_waveform(struct comedi_device *dev,
unsigned int channel, unsigned int range,
- unsigned long current_time)
+ unsigned int current_time)
{
enum {
SAWTOOTH_CHAN,
}
/*
- This is the background routine used to generate arbitrary data.
- It should run in the background; therefore it is scheduled by
- a timer mechanism.
-*/
+ * This is the background routine used to generate arbitrary data.
+ * It should run in the background; therefore it is scheduled by
+ * a timer mechanism.
+ */
static void waveform_ai_interrupt(unsigned long arg)
{
struct comedi_device *dev = (struct comedi_device *)arg;
num_scans = comedi_nscans_left(s, num_scans);
for (i = 0; i < num_scans; i++) {
+ unsigned long scan_remain_period = devpriv->scan_period;
+
for (j = 0; j < cmd->chanlist_len; j++) {
unsigned short sample;
+ if (devpriv->usec_current >= devpriv->usec_period)
+ devpriv->usec_current %= devpriv->usec_period;
sample = fake_waveform(dev, CR_CHAN(cmd->chanlist[j]),
CR_RANGE(cmd->chanlist[j]),
- devpriv->usec_current +
- i * devpriv->scan_period +
- j * devpriv->convert_period);
+ devpriv->usec_current);
comedi_buf_write_samples(s, &sample, 1);
+ devpriv->usec_current += devpriv->convert_period;
+ scan_remain_period -= devpriv->convert_period;
}
+ devpriv->usec_current += scan_remain_period;
}
-
- devpriv->usec_current += elapsed_time;
- devpriv->usec_current %= devpriv->usec_period;
+ if (devpriv->usec_current >= devpriv->usec_period)
+ devpriv->usec_current %= devpriv->usec_period;
if (cmd->stop_src == TRIG_COUNT && async->scans_done >= cmd->stop_arg)
async->events |= COMEDI_CB_EOA;
struct comedi_cmd *cmd)
{
int err = 0;
- unsigned int arg;
+ unsigned int arg, limit;
/* Step 1 : check if triggers are trivially valid */
err |= comedi_check_trigger_src(&cmd->start_src, TRIG_NOW);
- err |= comedi_check_trigger_src(&cmd->scan_begin_src, TRIG_TIMER);
+ err |= comedi_check_trigger_src(&cmd->scan_begin_src,
+ TRIG_FOLLOW | TRIG_TIMER);
err |= comedi_check_trigger_src(&cmd->convert_src,
TRIG_NOW | TRIG_TIMER);
err |= comedi_check_trigger_src(&cmd->scan_end_src, TRIG_COUNT);
/* Step 2b : and mutually compatible */
+ if (cmd->scan_begin_src == TRIG_FOLLOW && cmd->convert_src == TRIG_NOW)
+ err |= -EINVAL; /* scan period would be 0 */
+
if (err)
return 2;
err |= comedi_check_trigger_arg_is(&cmd->start_arg, 0);
- if (cmd->convert_src == TRIG_NOW)
+ if (cmd->convert_src == TRIG_NOW) {
err |= comedi_check_trigger_arg_is(&cmd->convert_arg, 0);
+ } else { /* cmd->convert_src == TRIG_TIMER */
+ if (cmd->scan_begin_src == TRIG_FOLLOW) {
+ err |= comedi_check_trigger_arg_min(&cmd->convert_arg,
+ NSEC_PER_USEC);
+ }
+ }
- if (cmd->scan_begin_src == TRIG_TIMER) {
+ if (cmd->scan_begin_src == TRIG_FOLLOW) {
+ err |= comedi_check_trigger_arg_is(&cmd->scan_begin_arg, 0);
+ } else { /* cmd->scan_begin_src == TRIG_TIMER */
err |= comedi_check_trigger_arg_min(&cmd->scan_begin_arg,
- nano_per_micro);
- if (cmd->convert_src == TRIG_TIMER) {
- err |= comedi_check_trigger_arg_min(&cmd->
- scan_begin_arg,
- cmd->convert_arg *
- cmd->chanlist_len);
- }
+ NSEC_PER_USEC);
}
err |= comedi_check_trigger_arg_min(&cmd->chanlist_len, 1);
if (cmd->stop_src == TRIG_COUNT)
err |= comedi_check_trigger_arg_min(&cmd->stop_arg, 1);
- else /* TRIG_NONE */
+ else /* cmd->stop_src == TRIG_NONE */
err |= comedi_check_trigger_arg_is(&cmd->stop_arg, 0);
if (err)
/* step 4: fix up any arguments */
- if (cmd->scan_begin_src == TRIG_TIMER) {
- arg = cmd->scan_begin_arg;
- /* round to nearest microsec */
- arg = nano_per_micro *
- ((arg + (nano_per_micro / 2)) / nano_per_micro);
- err |= comedi_check_trigger_arg_is(&cmd->scan_begin_arg, arg);
- }
if (cmd->convert_src == TRIG_TIMER) {
+ /* round convert_arg to nearest microsecond */
arg = cmd->convert_arg;
- /* round to nearest microsec */
- arg = nano_per_micro *
- ((arg + (nano_per_micro / 2)) / nano_per_micro);
+ arg = min(arg,
+ rounddown(UINT_MAX, (unsigned int)NSEC_PER_USEC));
+ arg = NSEC_PER_USEC * DIV_ROUND_CLOSEST(arg, NSEC_PER_USEC);
+ if (cmd->scan_begin_arg == TRIG_TIMER) {
+ /* limit convert_arg to keep scan_begin_arg in range */
+ limit = UINT_MAX / cmd->scan_end_arg;
+ limit = rounddown(limit, (unsigned int)NSEC_PER_SEC);
+ arg = min(arg, limit);
+ }
err |= comedi_check_trigger_arg_is(&cmd->convert_arg, arg);
}
+ if (cmd->scan_begin_src == TRIG_TIMER) {
+ /* round scan_begin_arg to nearest microsecond */
+ arg = cmd->scan_begin_arg;
+ arg = min(arg,
+ rounddown(UINT_MAX, (unsigned int)NSEC_PER_USEC));
+ arg = NSEC_PER_USEC * DIV_ROUND_CLOSEST(arg, NSEC_PER_USEC);
+ if (cmd->convert_src == TRIG_TIMER) {
+ /* but ensure scan_begin_arg is large enough */
+ arg = max(arg, cmd->convert_arg * cmd->scan_end_arg);
+ }
+ err |= comedi_check_trigger_arg_is(&cmd->scan_begin_arg, arg);
+ }
+
if (err)
return 4;
return -1;
}
- devpriv->scan_period = cmd->scan_begin_arg / nano_per_micro;
-
if (cmd->convert_src == TRIG_NOW)
devpriv->convert_period = 0;
- else /* TRIG_TIMER */
- devpriv->convert_period = cmd->convert_arg / nano_per_micro;
+ else /* cmd->convert_src == TRIG_TIMER */
+ devpriv->convert_period = cmd->convert_arg / NSEC_PER_USEC;
+
+ if (cmd->scan_begin_src == TRIG_FOLLOW) {
+ devpriv->scan_period = devpriv->convert_period *
+ cmd->scan_end_arg;
+ } else { /* cmd->scan_begin_src == TRIG_TIMER */
+ devpriv->scan_period = cmd->scan_begin_arg / NSEC_PER_USEC;
+ }
devpriv->last = ktime_get();
devpriv->usec_current =
(unsigned long)dev);
dev_info(dev->class_dev,
- "%s: %i microvolt, %li microsecond waveform attached\n",
+ "%s: %u microvolt, %u microsecond waveform attached\n",
dev->board_name,
devpriv->uvolt_amplitude, devpriv->usec_period);
projects / linux-2.6-block.git / blobdiff