2 comedi/drivers/das16m1.c
4 Author: Frank Mori Hess, based on code from the das16
6 Copyright (C) 2001 Frank Mori Hess <fmhess@users.sourceforge.net>
8 COMEDI - Linux Control and Measurement Device Interface
9 Copyright (C) 2000 David A. Schleef <ds@schleef.org>
11 This program is free software; you can redistribute it and/or modify
12 it under the terms of the GNU General Public License as published by
13 the Free Software Foundation; either version 2 of the License, or
14 (at your option) any later version.
16 This program is distributed in the hope that it will be useful,
17 but WITHOUT ANY WARRANTY; without even the implied warranty of
18 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 GNU General Public License for more details.
21 You should have received a copy of the GNU General Public License
22 along with this program; if not, write to the Free Software
23 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
25 ************************************************************************
29 Description: CIO-DAS16/M1
30 Author: Frank Mori Hess <fmhess@users.sourceforge.net>
31 Devices: [Measurement Computing] CIO-DAS16/M1 (das16m1)
34 This driver supports a single board - the CIO-DAS16/M1.
35 As far as I know, there are no other boards that have
36 the same register layout. Even the CIO-DAS16/M1/16 is
37 significantly different.
39 I was _barely_ able to reach the full 1 MHz capability
40 of this board, using a hard real-time interrupt
41 (set the TRIG_RT flag in your struct comedi_cmd and use
42 rtlinux or RTAI). The board can't do dma, so the bottleneck is
43 pulling the data across the ISA bus. I timed the interrupt
44 handler, and it took my computer ~470 microseconds to pull 512
45 samples from the board. So at 1 Mhz sampling rate,
46 expect your CPU to be spending almost all of its
47 time in the interrupt handler.
49 This board has some unusual restrictions for its channel/gain list. If the
50 list has 2 or more channels in it, then two conditions must be satisfied:
51 (1) - even/odd channels must appear at even/odd indices in the list
52 (2) - the list must have an even number of entries.
56 [1] - irq (optional, but you probably want it)
58 irq can be omitted, although the cmd interface will not work without it.
61 #include <linux/ioport.h>
62 #include <linux/interrupt.h>
63 #include "../comedidev.h"
67 #include "comedi_fc.h"
69 #define DAS16M1_SIZE 16
70 #define DAS16M1_SIZE2 8
72 #define DAS16M1_XTAL 100 /* 10 MHz master clock */
74 #define FIFO_SIZE 1024 /* 1024 sample fifo */
81 0 a/d bits 0-3, mux start 12 bit
82 1 a/d bits 4-11 unused
85 4 unused clear interrupt
87 6 channel/gain queue address
88 7 channel/gain queue data
96 #define DAS16M1_AI 0 /* 16-bit wide register */
97 #define AI_CHAN(x) ((x) & 0xf)
99 #define EXT_TRIG_BIT 0x1
102 #define DAS16M1_DIO 3
103 #define DAS16M1_CLEAR_INTR 4
104 #define DAS16M1_INTR_CONTROL 5
105 #define EXT_PACER 0x2
106 #define INT_PACER 0x3
107 #define PACER_MASK 0x3
109 #define DAS16M1_QUEUE_ADDR 6
110 #define DAS16M1_QUEUE_DATA 7
111 #define Q_CHAN(x) ((x) & 0x7)
112 #define Q_RANGE(x) (((x) & 0xf) << 4)
113 #define UNIPOLAR 0x40
114 #define DAS16M1_8254_FIRST 0x8
115 #define DAS16M1_8254_FIRST_CNTRL 0xb
116 #define TOTAL_CLEAR 0x30
117 #define DAS16M1_8254_SECOND 0xc
118 #define DAS16M1_82C55 0x400
119 #define DAS16M1_8254_THIRD 0x404
121 static const struct comedi_lrange range_das16m1 = { 9,
135 struct das16m1_private_struct {
136 unsigned int control_state;
137 volatile unsigned int adc_count; /* number of samples completed */
138 /* initial value in lower half of hardware conversion counter,
139 * needed to keep track of whether new count has been loaded into
140 * counter yet (loaded by first sample conversion) */
141 u16 initial_hw_count;
142 short ai_buffer[FIFO_SIZE];
143 unsigned int do_bits; /* saves status of digital output bits */
144 unsigned int divisor1; /* divides master clock to obtain conversion speed */
145 unsigned int divisor2; /* divides master clock to obtain conversion speed */
148 static inline short munge_sample(short data)
150 return (data >> 4) & 0xfff;
153 static void munge_sample_array(short *array, unsigned int num_elements)
157 for (i = 0; i < num_elements; i++)
158 array[i] = munge_sample(array[i]);
161 static int das16m1_cmd_test(struct comedi_device *dev,
162 struct comedi_subdevice *s, struct comedi_cmd *cmd)
164 struct das16m1_private_struct *devpriv = dev->private;
165 unsigned int err = 0, tmp, i;
167 /* Step 1 : check if triggers are trivially valid */
169 err |= cfc_check_trigger_src(&cmd->start_src, TRIG_NOW | TRIG_EXT);
170 err |= cfc_check_trigger_src(&cmd->scan_begin_src, TRIG_FOLLOW);
171 err |= cfc_check_trigger_src(&cmd->convert_src, TRIG_TIMER | TRIG_EXT);
172 err |= cfc_check_trigger_src(&cmd->scan_end_src, TRIG_COUNT);
173 err |= cfc_check_trigger_src(&cmd->stop_src, TRIG_COUNT | TRIG_NONE);
178 /* Step 2a : make sure trigger sources are unique */
180 err |= cfc_check_trigger_is_unique(cmd->start_src);
181 err |= cfc_check_trigger_is_unique(cmd->convert_src);
182 err |= cfc_check_trigger_is_unique(cmd->stop_src);
184 /* Step 2b : and mutually compatible */
189 /* Step 3: check if arguments are trivially valid */
191 err |= cfc_check_trigger_arg_is(&cmd->start_arg, 0);
193 if (cmd->scan_begin_src == TRIG_FOLLOW) /* internal trigger */
194 err |= cfc_check_trigger_arg_is(&cmd->scan_begin_arg, 0);
196 if (cmd->convert_src == TRIG_TIMER)
197 err |= cfc_check_trigger_arg_min(&cmd->convert_arg, 1000);
199 err |= cfc_check_trigger_arg_is(&cmd->scan_end_arg, cmd->chanlist_len);
201 if (cmd->stop_src == TRIG_COUNT) {
202 /* any count is allowed */
205 err |= cfc_check_trigger_arg_is(&cmd->stop_arg, 0);
211 /* step 4: fix up arguments */
213 if (cmd->convert_src == TRIG_TIMER) {
214 tmp = cmd->convert_arg;
215 /* calculate counter values that give desired timing */
216 i8253_cascade_ns_to_timer_2div(DAS16M1_XTAL,
217 &(devpriv->divisor1),
218 &(devpriv->divisor2),
220 cmd->flags & TRIG_ROUND_MASK);
221 if (tmp != cmd->convert_arg)
228 /* check chanlist against board's peculiarities */
229 if (cmd->chanlist && cmd->chanlist_len > 1) {
230 for (i = 0; i < cmd->chanlist_len; i++) {
231 /* even/odd channels must go into even/odd queue addresses */
232 if ((i % 2) != (CR_CHAN(cmd->chanlist[i]) % 2)) {
233 comedi_error(dev, "bad chanlist:\n"
234 " even/odd channels must go have even/odd chanlist indices");
238 if ((cmd->chanlist_len % 2) != 0) {
240 "chanlist must be of even length or length 1");
251 /* This function takes a time in nanoseconds and sets the *
252 * 2 pacer clocks to the closest frequency possible. It also *
253 * returns the actual sampling period. */
254 static unsigned int das16m1_set_pacer(struct comedi_device *dev,
255 unsigned int ns, int rounding_flags)
257 struct das16m1_private_struct *devpriv = dev->private;
259 i8253_cascade_ns_to_timer_2div(DAS16M1_XTAL, &(devpriv->divisor1),
260 &(devpriv->divisor2), &ns,
261 rounding_flags & TRIG_ROUND_MASK);
263 /* Write the values of ctr1 and ctr2 into counters 1 and 2 */
264 i8254_load(dev->iobase + DAS16M1_8254_SECOND, 0, 1, devpriv->divisor1,
266 i8254_load(dev->iobase + DAS16M1_8254_SECOND, 0, 2, devpriv->divisor2,
272 static int das16m1_cmd_exec(struct comedi_device *dev,
273 struct comedi_subdevice *s)
275 struct das16m1_private_struct *devpriv = dev->private;
276 struct comedi_async *async = s->async;
277 struct comedi_cmd *cmd = &async->cmd;
278 unsigned int byte, i;
281 comedi_error(dev, "irq required to execute comedi_cmd");
285 /* disable interrupts and internal pacer */
286 devpriv->control_state &= ~INTE & ~PACER_MASK;
287 outb(devpriv->control_state, dev->iobase + DAS16M1_INTR_CONTROL);
289 /* set software count */
290 devpriv->adc_count = 0;
291 /* Initialize lower half of hardware counter, used to determine how
292 * many samples are in fifo. Value doesn't actually load into counter
293 * until counter's next clock (the next a/d conversion) */
294 i8254_load(dev->iobase + DAS16M1_8254_FIRST, 0, 1, 0, 2);
295 /* remember current reading of counter so we know when counter has
296 * actually been loaded */
297 devpriv->initial_hw_count =
298 i8254_read(dev->iobase + DAS16M1_8254_FIRST, 0, 1);
299 /* setup channel/gain queue */
300 for (i = 0; i < cmd->chanlist_len; i++) {
301 outb(i, dev->iobase + DAS16M1_QUEUE_ADDR);
303 Q_CHAN(CR_CHAN(cmd->chanlist[i])) |
304 Q_RANGE(CR_RANGE(cmd->chanlist[i]));
305 outb(byte, dev->iobase + DAS16M1_QUEUE_DATA);
308 /* set counter mode and counts */
310 das16m1_set_pacer(dev, cmd->convert_arg,
311 cmd->flags & TRIG_ROUND_MASK);
313 /* set control & status register */
315 /* if we are using external start trigger (also board dislikes having
316 * both start and conversion triggers external simultaneously) */
317 if (cmd->start_src == TRIG_EXT && cmd->convert_src != TRIG_EXT)
318 byte |= EXT_TRIG_BIT;
320 outb(byte, dev->iobase + DAS16M1_CS);
321 /* clear interrupt bit */
322 outb(0, dev->iobase + DAS16M1_CLEAR_INTR);
324 /* enable interrupts and internal pacer */
325 devpriv->control_state &= ~PACER_MASK;
326 if (cmd->convert_src == TRIG_TIMER)
327 devpriv->control_state |= INT_PACER;
329 devpriv->control_state |= EXT_PACER;
331 devpriv->control_state |= INTE;
332 outb(devpriv->control_state, dev->iobase + DAS16M1_INTR_CONTROL);
337 static int das16m1_cancel(struct comedi_device *dev, struct comedi_subdevice *s)
339 struct das16m1_private_struct *devpriv = dev->private;
341 devpriv->control_state &= ~INTE & ~PACER_MASK;
342 outb(devpriv->control_state, dev->iobase + DAS16M1_INTR_CONTROL);
347 static int das16m1_ai_rinsn(struct comedi_device *dev,
348 struct comedi_subdevice *s,
349 struct comedi_insn *insn, unsigned int *data)
351 struct das16m1_private_struct *devpriv = dev->private;
354 const int timeout = 1000;
356 /* disable interrupts and internal pacer */
357 devpriv->control_state &= ~INTE & ~PACER_MASK;
358 outb(devpriv->control_state, dev->iobase + DAS16M1_INTR_CONTROL);
360 /* setup channel/gain queue */
361 outb(0, dev->iobase + DAS16M1_QUEUE_ADDR);
363 Q_CHAN(CR_CHAN(insn->chanspec)) | Q_RANGE(CR_RANGE(insn->chanspec));
364 outb(byte, dev->iobase + DAS16M1_QUEUE_DATA);
366 for (n = 0; n < insn->n; n++) {
367 /* clear IRQDATA bit */
368 outb(0, dev->iobase + DAS16M1_CLEAR_INTR);
369 /* trigger conversion */
370 outb(0, dev->iobase);
372 for (i = 0; i < timeout; i++) {
373 if (inb(dev->iobase + DAS16M1_CS) & IRQDATA)
377 comedi_error(dev, "timeout");
380 data[n] = munge_sample(inw(dev->iobase));
386 static int das16m1_di_rbits(struct comedi_device *dev,
387 struct comedi_subdevice *s,
388 struct comedi_insn *insn, unsigned int *data)
392 bits = inb(dev->iobase + DAS16M1_DIO) & 0xf;
399 static int das16m1_do_wbits(struct comedi_device *dev,
400 struct comedi_subdevice *s,
401 struct comedi_insn *insn, unsigned int *data)
403 struct das16m1_private_struct *devpriv = dev->private;
406 /* only set bits that have been masked */
408 wbits = devpriv->do_bits;
409 /* zero bits that have been masked */
411 /* set masked bits */
412 wbits |= data[0] & data[1];
413 devpriv->do_bits = wbits;
416 outb(devpriv->do_bits, dev->iobase + DAS16M1_DIO);
421 static void das16m1_handler(struct comedi_device *dev, unsigned int status)
423 struct das16m1_private_struct *devpriv = dev->private;
424 struct comedi_subdevice *s;
425 struct comedi_async *async;
426 struct comedi_cmd *cmd;
430 s = dev->read_subdev;
435 /* figure out how many samples are in fifo */
436 hw_counter = i8254_read(dev->iobase + DAS16M1_8254_FIRST, 0, 1);
437 /* make sure hardware counter reading is not bogus due to initial value
438 * not having been loaded yet */
439 if (devpriv->adc_count == 0 && hw_counter == devpriv->initial_hw_count) {
442 /* The calculation of num_samples looks odd, but it uses the following facts.
443 * 16 bit hardware counter is initialized with value of zero (which really
444 * means 0x1000). The counter decrements by one on each conversion
445 * (when the counter decrements from zero it goes to 0xffff). num_samples
446 * is a 16 bit variable, so it will roll over in a similar fashion to the
447 * hardware counter. Work it out, and this is what you get. */
448 num_samples = -hw_counter - devpriv->adc_count;
450 /* check if we only need some of the points */
451 if (cmd->stop_src == TRIG_COUNT) {
452 if (num_samples > cmd->stop_arg * cmd->chanlist_len)
453 num_samples = cmd->stop_arg * cmd->chanlist_len;
455 /* make sure we dont try to get too many points if fifo has overrun */
456 if (num_samples > FIFO_SIZE)
457 num_samples = FIFO_SIZE;
458 insw(dev->iobase, devpriv->ai_buffer, num_samples);
459 munge_sample_array(devpriv->ai_buffer, num_samples);
460 cfc_write_array_to_buffer(s, devpriv->ai_buffer,
461 num_samples * sizeof(short));
462 devpriv->adc_count += num_samples;
464 if (cmd->stop_src == TRIG_COUNT) {
465 if (devpriv->adc_count >= cmd->stop_arg * cmd->chanlist_len) { /* end of acquisition */
466 das16m1_cancel(dev, s);
467 async->events |= COMEDI_CB_EOA;
471 /* this probably won't catch overruns since the card doesn't generate
472 * overrun interrupts, but we might as well try */
473 if (status & OVRUN) {
474 das16m1_cancel(dev, s);
475 async->events |= COMEDI_CB_EOA | COMEDI_CB_ERROR;
476 comedi_error(dev, "fifo overflow");
479 comedi_event(dev, s);
483 static int das16m1_poll(struct comedi_device *dev, struct comedi_subdevice *s)
488 /* prevent race with interrupt handler */
489 spin_lock_irqsave(&dev->spinlock, flags);
490 status = inb(dev->iobase + DAS16M1_CS);
491 das16m1_handler(dev, status);
492 spin_unlock_irqrestore(&dev->spinlock, flags);
494 return s->async->buf_write_count - s->async->buf_read_count;
497 static irqreturn_t das16m1_interrupt(int irq, void *d)
500 struct comedi_device *dev = d;
502 if (!dev->attached) {
503 comedi_error(dev, "premature interrupt");
506 /* prevent race with comedi_poll() */
507 spin_lock(&dev->spinlock);
509 status = inb(dev->iobase + DAS16M1_CS);
511 if ((status & (IRQDATA | OVRUN)) == 0) {
512 comedi_error(dev, "spurious interrupt");
513 spin_unlock(&dev->spinlock);
517 das16m1_handler(dev, status);
519 /* clear interrupt */
520 outb(0, dev->iobase + DAS16M1_CLEAR_INTR);
522 spin_unlock(&dev->spinlock);
526 static int das16m1_irq_bits(unsigned int irq)
567 static int das16m1_attach(struct comedi_device *dev,
568 struct comedi_devconfig *it)
570 struct das16m1_private_struct *devpriv;
571 struct comedi_subdevice *s;
575 devpriv = kzalloc(sizeof(*devpriv), GFP_KERNEL);
578 dev->private = devpriv;
580 ret = comedi_request_region(dev, it->options[0], DAS16M1_SIZE);
583 /* Request an additional region for the 8255 */
584 ret = __comedi_request_region(dev, dev->iobase + DAS16M1_82C55,
587 release_region(dev->iobase, DAS16M1_SIZE);
592 /* now for the irq */
593 irq = it->options[1];
594 /* make sure it is valid */
595 if (das16m1_irq_bits(irq) >= 0) {
596 ret = request_irq(irq, das16m1_interrupt, 0,
597 dev->driver->driver_name, dev);
603 } else if (irq == 0) {
607 comedi_error(dev, "invalid irq\n"
608 " valid irqs are 2, 3, 5, 7, 10, 11, 12, or 15\n");
612 ret = comedi_alloc_subdevices(dev, 4);
616 s = &dev->subdevices[0];
617 dev->read_subdev = s;
619 s->type = COMEDI_SUBD_AI;
620 s->subdev_flags = SDF_READABLE | SDF_CMD_READ;
622 s->subdev_flags = SDF_DIFF;
623 s->len_chanlist = 256;
624 s->maxdata = (1 << 12) - 1;
625 s->range_table = &range_das16m1;
626 s->insn_read = das16m1_ai_rinsn;
627 s->do_cmdtest = das16m1_cmd_test;
628 s->do_cmd = das16m1_cmd_exec;
629 s->cancel = das16m1_cancel;
630 s->poll = das16m1_poll;
632 s = &dev->subdevices[1];
634 s->type = COMEDI_SUBD_DI;
635 s->subdev_flags = SDF_READABLE;
638 s->range_table = &range_digital;
639 s->insn_bits = das16m1_di_rbits;
641 s = &dev->subdevices[2];
643 s->type = COMEDI_SUBD_DO;
644 s->subdev_flags = SDF_WRITABLE | SDF_READABLE;
647 s->range_table = &range_digital;
648 s->insn_bits = das16m1_do_wbits;
650 s = &dev->subdevices[3];
652 subdev_8255_init(dev, s, NULL, dev->iobase + DAS16M1_82C55);
654 /* disable upper half of hardware conversion counter so it doesn't mess with us */
655 outb(TOTAL_CLEAR, dev->iobase + DAS16M1_8254_FIRST_CNTRL);
657 /* initialize digital output lines */
658 outb(devpriv->do_bits, dev->iobase + DAS16M1_DIO);
660 /* set the interrupt level */
662 devpriv->control_state = das16m1_irq_bits(dev->irq);
664 devpriv->control_state = 0;
665 outb(devpriv->control_state, dev->iobase + DAS16M1_INTR_CONTROL);
670 static void das16m1_detach(struct comedi_device *dev)
672 comedi_spriv_free(dev, 3);
674 free_irq(dev->irq, dev);
676 release_region(dev->iobase, DAS16M1_SIZE);
677 release_region(dev->iobase + DAS16M1_82C55, DAS16M1_SIZE2);
681 static struct comedi_driver das16m1_driver = {
682 .driver_name = "das16m1",
683 .module = THIS_MODULE,
684 .attach = das16m1_attach,
685 .detach = das16m1_detach,
687 module_comedi_driver(das16m1_driver);
689 MODULE_AUTHOR("Comedi http://www.comedi.org");
690 MODULE_DESCRIPTION("Comedi low-level driver");
691 MODULE_LICENSE("GPL");