--- /dev/null
+/*
+ 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.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+************************************************************************/
+/*
+Driver: 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 "../comedidev.h"
+
+#include <asm/div64.h>
+
+#include "comedi_fc.h"
+
+/* Board descriptions */
+typedef struct waveform_board_struct {
+ const char *name;
+ int ai_chans;
+ int ai_bits;
+ int have_dio;
+} waveform_board;
+
+#define N_CHANS 8
+
+static const waveform_board waveform_boards[] = {
+ {
+ name: "comedi_test",
+ ai_chans:N_CHANS,
+ ai_bits: 16,
+ have_dio:0,
+ },
+};
+
+#define thisboard ((const waveform_board *)dev->board_ptr)
+
+/* Data unique to this driver */
+typedef struct {
+ struct timer_list timer;
+ struct timeval last; // time at which last timer interrupt occured
+ unsigned int uvolt_amplitude; // waveform amplitude in microvolts
+ unsigned long usec_period; // waveform period in microseconds
+ volatile unsigned long usec_current; // current time (modulo waveform period)
+ volatile unsigned long usec_remainder; // usec since last scan;
+ volatile unsigned long ai_count; // number of conversions remaining
+ unsigned int scan_period; // scan period in usec
+ unsigned int convert_period; // conversion period in usec
+ volatile unsigned timer_running:1;
+ volatile lsampl_t ao_loopbacks[N_CHANS];
+} waveform_private;
+#define devpriv ((waveform_private *)dev->private)
+
+static int waveform_attach(comedi_device * dev, comedi_devconfig * it);
+static int waveform_detach(comedi_device * dev);
+static comedi_driver driver_waveform = {
+ driver_name:"comedi_test",
+ module:THIS_MODULE,
+ attach:waveform_attach,
+ detach:waveform_detach,
+ board_name:&waveform_boards[0].name,
+ offset:sizeof(waveform_board),
+ num_names:sizeof(waveform_boards) / sizeof(waveform_board),
+};
+
+COMEDI_INITCLEANUP(driver_waveform);
+
+static int waveform_ai_cmdtest(comedi_device * dev, comedi_subdevice * s,
+ comedi_cmd * cmd);
+static int waveform_ai_cmd(comedi_device * dev, comedi_subdevice * s);
+static int waveform_ai_cancel(comedi_device * dev, comedi_subdevice * s);
+static int waveform_ai_insn_read(comedi_device * dev, comedi_subdevice * s,
+ comedi_insn * insn, lsampl_t * data);
+static int waveform_ao_insn_write(comedi_device * dev, comedi_subdevice * s,
+ comedi_insn * insn, lsampl_t * data);
+static sampl_t fake_sawtooth(comedi_device * dev, unsigned int range,
+ unsigned long current_time);
+static sampl_t fake_squarewave(comedi_device * dev, unsigned int range,
+ unsigned long current_time);
+static sampl_t fake_flatline(comedi_device * dev, unsigned int range,
+ unsigned long current_time);
+static sampl_t fake_waveform(comedi_device * dev, unsigned int channel,
+ unsigned int range, unsigned long current_time);
+
+static const int nano_per_micro = 1000; // 1000 nanosec in a microsec
+
+// fake analog input ranges
+static const comedi_lrange waveform_ai_ranges = {
+ 2,
+ {
+ BIP_RANGE(10),
+ BIP_RANGE(5),
+ }
+};
+
+/*
+ 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)
+{
+ comedi_device *dev = (comedi_device *) arg;
+ comedi_async *async = dev->read_subdev->async;
+ comedi_cmd *cmd = &async->cmd;
+ unsigned int i, j;
+ // all times in microsec
+ unsigned long elapsed_time;
+ unsigned int num_scans;
+ struct timeval now;
+
+ do_gettimeofday(&now);
+
+ elapsed_time =
+ 1000000 * (now.tv_sec - devpriv->last.tv_sec) + now.tv_usec -
+ devpriv->last.tv_usec;
+ devpriv->last = now;
+ num_scans =
+ (devpriv->usec_remainder + elapsed_time) / devpriv->scan_period;
+ devpriv->usec_remainder =
+ (devpriv->usec_remainder + elapsed_time) % devpriv->scan_period;
+ async->events = 0;
+
+ for (i = 0; i < num_scans; i++) {
+ for (j = 0; j < cmd->chanlist_len; j++) {
+ cfc_write_to_buffer(dev->read_subdev,
+ 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->ai_count++;
+ if (cmd->stop_src == TRIG_COUNT
+ && devpriv->ai_count >= cmd->stop_arg) {
+ async->events |= COMEDI_CB_EOA;
+ break;
+ }
+ }
+
+ devpriv->usec_current += elapsed_time;
+ devpriv->usec_current %= devpriv->usec_period;
+
+ if ((async->events & COMEDI_CB_EOA) == 0 && devpriv->timer_running)
+ mod_timer(&devpriv->timer, jiffies + 1);
+ else
+ del_timer(&devpriv->timer);
+
+ comedi_event(dev, dev->read_subdev);
+}
+
+static int waveform_attach(comedi_device * dev, comedi_devconfig * it)
+{
+ comedi_subdevice *s;
+ int amplitude = it->options[0];
+ int period = it->options[1];
+
+ printk("comedi%d: comedi_test: ", dev->minor);
+
+ dev->board_name = thisboard->name;
+
+ if (alloc_private(dev, sizeof(waveform_private)) < 0)
+ return -ENOMEM;
+
+ // set default amplitude and period
+ if (amplitude <= 0)
+ amplitude = 1000000; // 1 volt
+ if (period <= 0)
+ period = 100000; // 0.1 sec
+
+ devpriv->uvolt_amplitude = amplitude;
+ devpriv->usec_period = period;
+
+ printk("%i microvolt, %li microsecond waveform ",
+ devpriv->uvolt_amplitude, devpriv->usec_period);
+ dev->n_subdevices = 2;
+ if (alloc_subdevices(dev, dev->n_subdevices) < 0)
+ return -ENOMEM;
+
+ s = dev->subdevices + 0;
+ dev->read_subdev = s;
+ /* analog input subdevice */
+ s->type = COMEDI_SUBD_AI;
+ s->subdev_flags = SDF_READABLE | SDF_GROUND | SDF_CMD_READ;
+ s->n_chan = thisboard->ai_chans;
+ s->maxdata = (1 << thisboard->ai_bits) - 1;
+ s->range_table = &waveform_ai_ranges;
+ s->len_chanlist = s->n_chan * 2;
+ s->insn_read = waveform_ai_insn_read;
+ s->do_cmd = waveform_ai_cmd;
+ s->do_cmdtest = waveform_ai_cmdtest;
+ s->cancel = waveform_ai_cancel;
+
+ s = dev->subdevices + 1;
+ dev->write_subdev = s;
+ /* analog output subdevice (loopback) */
+ s->type = COMEDI_SUBD_AO;
+ s->subdev_flags = SDF_WRITEABLE | SDF_GROUND;
+ s->n_chan = thisboard->ai_chans;
+ s->maxdata = (1 << thisboard->ai_bits) - 1;
+ s->range_table = &waveform_ai_ranges;
+ s->len_chanlist = s->n_chan * 2;
+ s->insn_write = waveform_ao_insn_write;
+ s->do_cmd = 0;
+ s->do_cmdtest = 0;
+ s->cancel = 0;
+ {
+ /* Our default loopback value is just a 0V flatline */
+ int i;
+ for (i = 0; i < s->n_chan; i++)
+ devpriv->ao_loopbacks[i] = s->maxdata / 2;
+ }
+
+ init_timer(&(devpriv->timer));
+ devpriv->timer.function = waveform_ai_interrupt;
+ devpriv->timer.data = (unsigned long)dev;
+
+ printk("attached\n");
+
+ return 1;
+}
+
+static int waveform_detach(comedi_device * dev)
+{
+ printk("comedi%d: comedi_test: remove\n", dev->minor);
+
+ if (dev->private) {
+ waveform_ai_cancel(dev, dev->read_subdev);
+ }
+
+ return 0;
+}
+
+static int waveform_ai_cmdtest(comedi_device * dev, comedi_subdevice * s,
+ comedi_cmd * cmd)
+{
+ int err = 0;
+ int tmp;
+
+ /* step 1: make sure trigger sources are trivially valid */
+
+ tmp = cmd->start_src;
+ cmd->start_src &= TRIG_NOW;
+ if (!cmd->start_src || tmp != cmd->start_src)
+ err++;
+
+ tmp = cmd->scan_begin_src;
+ cmd->scan_begin_src &= TRIG_TIMER;
+ if (!cmd->scan_begin_src || tmp != cmd->scan_begin_src)
+ err++;
+
+ tmp = cmd->convert_src;
+ cmd->convert_src &= TRIG_NOW | TRIG_TIMER;
+ if (!cmd->convert_src || tmp != cmd->convert_src)
+ err++;
+
+ tmp = cmd->scan_end_src;
+ cmd->scan_end_src &= TRIG_COUNT;
+ if (!cmd->scan_end_src || tmp != cmd->scan_end_src)
+ err++;
+
+ tmp = cmd->stop_src;
+ cmd->stop_src &= TRIG_COUNT | TRIG_NONE;
+ if (!cmd->stop_src || tmp != cmd->stop_src)
+ err++;
+
+ if (err)
+ return 1;
+
+ /* step 2: make sure trigger sources are unique and mutually compatible */
+
+ if (cmd->convert_src != TRIG_NOW && cmd->convert_src != TRIG_TIMER)
+ err++;
+ if (cmd->stop_src != TRIG_COUNT && cmd->stop_src != TRIG_NONE)
+ err++;
+
+ if (err)
+ return 2;
+
+ /* step 3: make sure arguments are trivially compatible */
+
+ if (cmd->start_arg != 0) {
+ cmd->start_arg = 0;
+ err++;
+ }
+ if (cmd->convert_src == TRIG_NOW) {
+ if (cmd->convert_arg != 0) {
+ cmd->convert_arg = 0;
+ err++;
+ }
+ }
+ if (cmd->scan_begin_src == TRIG_TIMER) {
+ if (cmd->scan_begin_arg < nano_per_micro) {
+ cmd->scan_begin_arg = nano_per_micro;
+ err++;
+ }
+ if (cmd->convert_src == TRIG_TIMER &&
+ cmd->scan_begin_arg <
+ cmd->convert_arg * cmd->chanlist_len) {
+ cmd->scan_begin_arg =
+ cmd->convert_arg * cmd->chanlist_len;
+ err++;
+ }
+ }
+ // XXX these checks are generic and should go in core if not there already
+ if (!cmd->chanlist_len) {
+ cmd->chanlist_len = 1;
+ err++;
+ }
+ if (cmd->scan_end_arg != cmd->chanlist_len) {
+ cmd->scan_end_arg = cmd->chanlist_len;
+ err++;
+ }
+
+ if (cmd->stop_src == TRIG_COUNT) {
+ if (!cmd->stop_arg) {
+ cmd->stop_arg = 1;
+ err++;
+ }
+ } else { /* TRIG_NONE */
+ if (cmd->stop_arg != 0) {
+ cmd->stop_arg = 0;
+ err++;
+ }
+ }
+
+ if (err)
+ return 3;
+
+ /* step 4: fix up any arguments */
+
+ if (cmd->scan_begin_src == TRIG_TIMER) {
+ tmp = cmd->scan_begin_arg;
+ // round to nearest microsec
+ cmd->scan_begin_arg =
+ nano_per_micro * ((tmp +
+ (nano_per_micro / 2)) / nano_per_micro);
+ if (tmp != cmd->scan_begin_arg)
+ err++;
+ }
+ if (cmd->convert_src == TRIG_TIMER) {
+ tmp = cmd->convert_arg;
+ // round to nearest microsec
+ cmd->convert_arg =
+ nano_per_micro * ((tmp +
+ (nano_per_micro / 2)) / nano_per_micro);
+ if (tmp != cmd->convert_arg)
+ err++;
+ }
+
+ if (err)
+ return 4;
+
+ return 0;
+}
+
+static int waveform_ai_cmd(comedi_device * dev, comedi_subdevice * s)
+{
+ comedi_cmd *cmd = &s->async->cmd;
+
+ if (cmd->flags & TRIG_RT) {
+ comedi_error(dev,
+ "commands at RT priority not supported in this driver");
+ return -1;
+ }
+
+ devpriv->timer_running = 1;
+ devpriv->ai_count = 0;
+ devpriv->scan_period = cmd->scan_begin_arg / nano_per_micro;
+
+ if (cmd->convert_src == TRIG_NOW)
+ devpriv->convert_period = 0;
+ else if (cmd->convert_src == TRIG_TIMER)
+ devpriv->convert_period = cmd->convert_arg / nano_per_micro;
+ else {
+ comedi_error(dev, "bug setting conversion period");
+ return -1;
+ }
+
+ do_gettimeofday(&devpriv->last);
+ devpriv->usec_current = devpriv->last.tv_usec % devpriv->usec_period;
+ devpriv->usec_remainder = 0;
+
+ devpriv->timer.expires = jiffies + 1;
+ add_timer(&devpriv->timer);
+ return 0;
+}
+
+static int waveform_ai_cancel(comedi_device * dev, comedi_subdevice * s)
+{
+ devpriv->timer_running = 0;
+ del_timer(&devpriv->timer);
+ return 0;
+}
+
+static sampl_t fake_sawtooth(comedi_device * dev, unsigned int range_index,
+ unsigned long current_time)
+{
+ comedi_subdevice *s = dev->read_subdev;
+ unsigned int offset = s->maxdata / 2;
+ u64 value;
+ const comedi_krange *krange = &s->range_table->range[range_index];
+ u64 binary_amplitude;
+
+ binary_amplitude = s->maxdata;
+ 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
+
+ return offset + value;
+}
+static sampl_t fake_squarewave(comedi_device * dev, unsigned int range_index,
+ unsigned long current_time)
+{
+ comedi_subdevice *s = dev->read_subdev;
+ unsigned int offset = s->maxdata / 2;
+ u64 value;
+ const 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;
+
+ return offset + value;
+}
+
+static sampl_t fake_flatline(comedi_device * dev, unsigned int range_index,
+ unsigned long current_time)
+{
+ return dev->read_subdev->maxdata / 2;
+}
+
+// generates a different waveform depending on what channel is read
+static sampl_t fake_waveform(comedi_device * dev, unsigned int channel,
+ unsigned int range, unsigned long current_time)
+{
+ enum {
+ SAWTOOTH_CHAN,
+ SQUARE_CHAN,
+ };
+ switch (channel) {
+ case SAWTOOTH_CHAN:
+ return fake_sawtooth(dev, range, current_time);
+ break;
+ case SQUARE_CHAN:
+ return fake_squarewave(dev, range, current_time);
+ break;
+ default:
+ break;
+ }
+
+ return fake_flatline(dev, range, current_time);
+}
+
+static int waveform_ai_insn_read(comedi_device * dev, comedi_subdevice * s,
+ comedi_insn * insn, lsampl_t * data)
+{
+ int i, chan = CR_CHAN(insn->chanspec);
+
+ for (i = 0; i < insn->n; i++)
+ data[i] = devpriv->ao_loopbacks[chan];
+
+ return insn->n;
+}
+
+static int waveform_ao_insn_write(comedi_device * dev, comedi_subdevice * s,
+ comedi_insn * insn, lsampl_t * data)
+{
+ int i, chan = CR_CHAN(insn->chanspec);
+
+ for (i = 0; i < insn->n; i++)
+ devpriv->ao_loopbacks[chan] = data[i];
+
+ return insn->n;
+}
projects / GitHub / MotorolaMobilityLLC / kernel-slsi.git / commitdiff