Staging: comedi: add comedi_test driver

# Comedi "helper" modules

obj-$(CONFIG_COMEDI)			+= comedi_fc.o

obj-$(CONFIG_COMEDI)			+= comedi_bond.o

obj-$(CONFIG_COMEDI)			+= comedi_test.o

# Comedi PCI drivers

obj-$(CONFIG_COMEDI_PCI_DRIVERS)	+= mite.o

/*

    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;

}