1 /*======================================================================
2
3 comedi/drivers/quatech_daqp_cs.c
4
5 Quatech DAQP PCMCIA data capture cards COMEDI client driver
6 Copyright (C) 2000, 2003 Brent Baccala <baccala@freesoft.org>
7 The DAQP interface code in this file is released into the public domain.
8
9 COMEDI - Linux Control and Measurement Device Interface
10 Copyright (C) 1998 David A. Schleef <ds@schleef.org>
11 http://www.comedi.org/
12
13 quatech_daqp_cs.c 1.10
14
15 Documentation for the DAQP PCMCIA cards can be found on Quatech's site:
16
17 ftp://ftp.quatech.com/Manuals/daqp-208.pdf
18
19 This manual is for both the DAQP-208 and the DAQP-308.
20
21 What works:
22
23 - A/D conversion
24 - 8 channels
25 - 4 gain ranges
26 - ground ref or differential
27 - single-shot and timed both supported
28 - D/A conversion, single-shot
29 - digital I/O
30
31 What doesn't:
32
33 - any kind of triggering - external or D/A channel 1
34 - the card's optional expansion board
35 - the card's timer (for anything other than A/D conversion)
36 - D/A update modes other than immediate (i.e, timed)
37 - fancier timing modes
38 - setting card's FIFO buffer thresholds to anything but default
39
40 ======================================================================*/
41
42 /*
43 Driver: quatech_daqp_cs
44 Description: Quatech DAQP PCMCIA data capture cards
45 Author: Brent Baccala <baccala@freesoft.org>
46 Status: works
47 Devices: [Quatech] DAQP-208 (daqp), DAQP-308
48 */
49
50 #include "../comedidev.h"
51 #include <linux/semaphore.h>
52
53 #include <pcmcia/cistpl.h>
54 #include <pcmcia/cisreg.h>
55 #include <pcmcia/ds.h>
56
57 #include <linux/completion.h>
58
59 /* Maximum number of separate DAQP devices we'll allow */
60 #define MAX_DEV 4
61
62 struct local_info_t {
63 struct pcmcia_device *link;
64 int stop;
65 int table_index;
66 char board_name[32];
67
68 enum { semaphore, buffer } interrupt_mode;
69
70 struct completion eos;
71
72 struct comedi_device *dev;
73 struct comedi_subdevice *s;
74 int count;
75 };
76
77 /* A list of "instances" of the device. */
78
79 static struct local_info_t *dev_table[MAX_DEV] = { NULL, /* ... */ };
80
81 /* The DAQP communicates with the system through a 16 byte I/O window. */
82
83 #define DAQP_FIFO_SIZE 4096
84
85 #define DAQP_FIFO 0
86 #define DAQP_SCANLIST 1
87 #define DAQP_CONTROL 2
88 #define DAQP_STATUS 2
89 #define DAQP_DIGITAL_IO 3
90 #define DAQP_PACER_LOW 4
91 #define DAQP_PACER_MID 5
92 #define DAQP_PACER_HIGH 6
93 #define DAQP_COMMAND 7
94 #define DAQP_DA 8
95 #define DAQP_TIMER 10
96 #define DAQP_AUX 15
97
98 #define DAQP_SCANLIST_DIFFERENTIAL 0x4000
99 #define DAQP_SCANLIST_GAIN(x) ((x)<<12)
100 #define DAQP_SCANLIST_CHANNEL(x) ((x)<<8)
101 #define DAQP_SCANLIST_START 0x0080
102 #define DAQP_SCANLIST_EXT_GAIN(x) ((x)<<4)
103 #define DAQP_SCANLIST_EXT_CHANNEL(x) (x)
104
105 #define DAQP_CONTROL_PACER_100kHz 0xc0
106 #define DAQP_CONTROL_PACER_1MHz 0x80
107 #define DAQP_CONTROL_PACER_5MHz 0x40
108 #define DAQP_CONTROL_PACER_EXTERNAL 0x00
109 #define DAQP_CONTORL_EXPANSION 0x20
110 #define DAQP_CONTROL_EOS_INT_ENABLE 0x10
111 #define DAQP_CONTROL_FIFO_INT_ENABLE 0x08
112 #define DAQP_CONTROL_TRIGGER_ONESHOT 0x00
113 #define DAQP_CONTROL_TRIGGER_CONTINUOUS 0x04
114 #define DAQP_CONTROL_TRIGGER_INTERNAL 0x00
115 #define DAQP_CONTROL_TRIGGER_EXTERNAL 0x02
116 #define DAQP_CONTROL_TRIGGER_RISING 0x00
117 #define DAQP_CONTROL_TRIGGER_FALLING 0x01
118
119 #define DAQP_STATUS_IDLE 0x80
120 #define DAQP_STATUS_RUNNING 0x40
121 #define DAQP_STATUS_EVENTS 0x38
122 #define DAQP_STATUS_DATA_LOST 0x20
123 #define DAQP_STATUS_END_OF_SCAN 0x10
124 #define DAQP_STATUS_FIFO_THRESHOLD 0x08
125 #define DAQP_STATUS_FIFO_FULL 0x04
126 #define DAQP_STATUS_FIFO_NEARFULL 0x02
127 #define DAQP_STATUS_FIFO_EMPTY 0x01
128
129 #define DAQP_COMMAND_ARM 0x80
130 #define DAQP_COMMAND_RSTF 0x40
131 #define DAQP_COMMAND_RSTQ 0x20
132 #define DAQP_COMMAND_STOP 0x10
133 #define DAQP_COMMAND_LATCH 0x08
134 #define DAQP_COMMAND_100kHz 0x00
135 #define DAQP_COMMAND_50kHz 0x02
136 #define DAQP_COMMAND_25kHz 0x04
137 #define DAQP_COMMAND_FIFO_DATA 0x01
138 #define DAQP_COMMAND_FIFO_PROGRAM 0x00
139
140 #define DAQP_AUX_TRIGGER_TTL 0x00
141 #define DAQP_AUX_TRIGGER_ANALOG 0x80
142 #define DAQP_AUX_TRIGGER_PRETRIGGER 0x40
143 #define DAQP_AUX_TIMER_INT_ENABLE 0x20
144 #define DAQP_AUX_TIMER_RELOAD 0x00
145 #define DAQP_AUX_TIMER_PAUSE 0x08
146 #define DAQP_AUX_TIMER_GO 0x10
147 #define DAQP_AUX_TIMER_GO_EXTERNAL 0x18
148 #define DAQP_AUX_TIMER_EXTERNAL_SRC 0x04
149 #define DAQP_AUX_TIMER_INTERNAL_SRC 0x00
150 #define DAQP_AUX_DA_DIRECT 0x00
151 #define DAQP_AUX_DA_OVERFLOW 0x01
152 #define DAQP_AUX_DA_EXTERNAL 0x02
153 #define DAQP_AUX_DA_PACER 0x03
154
155 #define DAQP_AUX_RUNNING 0x80
156 #define DAQP_AUX_TRIGGERED 0x40
157 #define DAQP_AUX_DA_BUFFER 0x20
158 #define DAQP_AUX_TIMER_OVERFLOW 0x10
159 #define DAQP_AUX_CONVERSION 0x08
160 #define DAQP_AUX_DATA_LOST 0x04
161 #define DAQP_AUX_FIFO_NEARFULL 0x02
162 #define DAQP_AUX_FIFO_EMPTY 0x01
163
164 /* These range structures tell COMEDI how the sample values map to
165 * voltages. The A/D converter has four .ranges = +/- 10V through
166 * +/- 1.25V, and the D/A converter has only .one = +/- 5V.
167 */
168
169 static const struct comedi_lrange range_daqp_ai = { 4, {
170 BIP_RANGE(10),
171 BIP_RANGE(5),
172 BIP_RANGE(2.5),
173 BIP_RANGE(1.25)
174 }
175 };
176
177 static const struct comedi_lrange range_daqp_ao = { 1, {BIP_RANGE(5)} };
178
179 /*====================================================================*/
180
181 /* comedi interface code */
182
183 static int daqp_attach(struct comedi_device *dev, struct comedi_devconfig *it);
184 static int daqp_detach(struct comedi_device *dev);
185 static struct comedi_driver driver_daqp = {
186 .driver_name = "quatech_daqp_cs",
187 .module = THIS_MODULE,
188 .attach = daqp_attach,
189 .detach = daqp_detach,
190 };
191
192 #ifdef DAQP_DEBUG
193
daqp_dump(struct comedi_device * dev)194 static void daqp_dump(struct comedi_device *dev)
195 {
196 printk(KERN_INFO "DAQP: status %02x; aux status %02x\n",
197 inb(dev->iobase + DAQP_STATUS), inb(dev->iobase + DAQP_AUX));
198 }
199
hex_dump(char * str,void * ptr,int len)200 static void hex_dump(char *str, void *ptr, int len)
201 {
202 unsigned char *cptr = ptr;
203 int i;
204
205 printk(str);
206
207 for (i = 0; i < len; i++) {
208 if (i % 16 == 0)
209 printk("\n%p:", cptr);
210
211 printk(" %02x", *(cptr++));
212 }
213 printk("\n");
214 }
215
216 #endif
217
218 /* Cancel a running acquisition */
219
daqp_ai_cancel(struct comedi_device * dev,struct comedi_subdevice * s)220 static int daqp_ai_cancel(struct comedi_device *dev, struct comedi_subdevice *s)
221 {
222 struct local_info_t *local = (struct local_info_t *)s->private;
223
224 if (local->stop)
225 return -EIO;
226
227
228 outb(DAQP_COMMAND_STOP, dev->iobase + DAQP_COMMAND);
229
230 /* flush any linguring data in FIFO - superfluous here */
231 /* outb(DAQP_COMMAND_RSTF, dev->iobase+DAQP_COMMAND); */
232
233 local->interrupt_mode = semaphore;
234
235 return 0;
236 }
237
238 /* Interrupt handler
239 *
240 * Operates in one of two modes. If local->interrupt_mode is
241 * 'semaphore', just signal the local->eos completion and return
242 * (one-shot mode). Otherwise (continuous mode), read data in from
243 * the card, transfer it to the buffer provided by the higher-level
244 * comedi kernel module, and signal various comedi callback routines,
245 * which run pretty quick.
246 */
daqp_interrupt(int irq,void * dev_id)247 static enum irqreturn daqp_interrupt(int irq, void *dev_id)
248 {
249 struct local_info_t *local = (struct local_info_t *)dev_id;
250 struct comedi_device *dev;
251 struct comedi_subdevice *s;
252 int loop_limit = 10000;
253 int status;
254
255 if (local == NULL) {
256 printk(KERN_WARNING
257 "daqp_interrupt(): irq %d for unknown device.\n", irq);
258 return IRQ_NONE;
259 }
260
261 dev = local->dev;
262 if (dev == NULL) {
263 printk(KERN_WARNING "daqp_interrupt(): NULL comedi_device.\n");
264 return IRQ_NONE;
265 }
266
267 if (!dev->attached) {
268 printk(KERN_WARNING
269 "daqp_interrupt(): struct comedi_device not yet attached.\n");
270 return IRQ_NONE;
271 }
272
273 s = local->s;
274 if (s == NULL) {
275 printk(KERN_WARNING
276 "daqp_interrupt(): NULL comedi_subdevice.\n");
277 return IRQ_NONE;
278 }
279
280 if ((struct local_info_t *)s->private != local) {
281 printk(KERN_WARNING
282 "daqp_interrupt(): invalid comedi_subdevice.\n");
283 return IRQ_NONE;
284 }
285
286 switch (local->interrupt_mode) {
287
288 case semaphore:
289
290 complete(&local->eos);
291 break;
292
293 case buffer:
294
295 while (!((status = inb(dev->iobase + DAQP_STATUS))
296 & DAQP_STATUS_FIFO_EMPTY)) {
297
298 short data;
299
300 if (status & DAQP_STATUS_DATA_LOST) {
301 s->async->events |=
302 COMEDI_CB_EOA | COMEDI_CB_OVERFLOW;
303 printk("daqp: data lost\n");
304 daqp_ai_cancel(dev, s);
305 break;
306 }
307
308 data = inb(dev->iobase + DAQP_FIFO);
309 data |= inb(dev->iobase + DAQP_FIFO) << 8;
310 data ^= 0x8000;
311
312 comedi_buf_put(s->async, data);
313
314 /* If there's a limit, decrement it
315 * and stop conversion if zero
316 */
317
318 if (local->count > 0) {
319 local->count--;
320 if (local->count == 0) {
321 daqp_ai_cancel(dev, s);
322 s->async->events |= COMEDI_CB_EOA;
323 break;
324 }
325 }
326
327 if ((loop_limit--) <= 0)
328 break;
329 }
330
331 if (loop_limit <= 0) {
332 printk(KERN_WARNING
333 "loop_limit reached in daqp_interrupt()\n");
334 daqp_ai_cancel(dev, s);
335 s->async->events |= COMEDI_CB_EOA | COMEDI_CB_ERROR;
336 }
337
338 s->async->events |= COMEDI_CB_BLOCK;
339
340 comedi_event(dev, s);
341 }
342 return IRQ_HANDLED;
343 }
344
345 /* One-shot analog data acquisition routine */
346
daqp_ai_insn_read(struct comedi_device * dev,struct comedi_subdevice * s,struct comedi_insn * insn,unsigned int * data)347 static int daqp_ai_insn_read(struct comedi_device *dev,
348 struct comedi_subdevice *s,
349 struct comedi_insn *insn, unsigned int *data)
350 {
351 struct local_info_t *local = (struct local_info_t *)s->private;
352 int i;
353 int v;
354 int counter = 10000;
355
356 if (local->stop)
357 return -EIO;
358
359
360 /* Stop any running conversion */
361 daqp_ai_cancel(dev, s);
362
363 outb(0, dev->iobase + DAQP_AUX);
364
365 /* Reset scan list queue */
366 outb(DAQP_COMMAND_RSTQ, dev->iobase + DAQP_COMMAND);
367
368 /* Program one scan list entry */
369
370 v = DAQP_SCANLIST_CHANNEL(CR_CHAN(insn->chanspec))
371 | DAQP_SCANLIST_GAIN(CR_RANGE(insn->chanspec));
372
373 if (CR_AREF(insn->chanspec) == AREF_DIFF)
374 v |= DAQP_SCANLIST_DIFFERENTIAL;
375
376
377 v |= DAQP_SCANLIST_START;
378
379 outb(v & 0xff, dev->iobase + DAQP_SCANLIST);
380 outb(v >> 8, dev->iobase + DAQP_SCANLIST);
381
382 /* Reset data FIFO (see page 28 of DAQP User's Manual) */
383
384 outb(DAQP_COMMAND_RSTF, dev->iobase + DAQP_COMMAND);
385
386 /* Set trigger */
387
388 v = DAQP_CONTROL_TRIGGER_ONESHOT | DAQP_CONTROL_TRIGGER_INTERNAL
389 | DAQP_CONTROL_PACER_100kHz | DAQP_CONTROL_EOS_INT_ENABLE;
390
391 outb(v, dev->iobase + DAQP_CONTROL);
392
393 /* Reset any pending interrupts (my card has a tendency to require
394 * require multiple reads on the status register to achieve this)
395 */
396
397 while (--counter
398 && (inb(dev->iobase + DAQP_STATUS) & DAQP_STATUS_EVENTS)) ;
399 if (!counter) {
400 printk("daqp: couldn't clear interrupts in status register\n");
401 return -1;
402 }
403
404 init_completion(&local->eos);
405 local->interrupt_mode = semaphore;
406 local->dev = dev;
407 local->s = s;
408
409 for (i = 0; i < insn->n; i++) {
410
411 /* Start conversion */
412 outb(DAQP_COMMAND_ARM | DAQP_COMMAND_FIFO_DATA,
413 dev->iobase + DAQP_COMMAND);
414
415 /* Wait for interrupt service routine to unblock completion */
416 /* Maybe could use a timeout here, but it's interruptible */
417 if (wait_for_completion_interruptible(&local->eos))
418 return -EINTR;
419
420 data[i] = inb(dev->iobase + DAQP_FIFO);
421 data[i] |= inb(dev->iobase + DAQP_FIFO) << 8;
422 data[i] ^= 0x8000;
423 }
424
425 return insn->n;
426 }
427
428 /* This function converts ns nanoseconds to a counter value suitable
429 * for programming the device. We always use the DAQP's 5 MHz clock,
430 * which with its 24-bit counter, allows values up to 84 seconds.
431 * Also, the function adjusts ns so that it cooresponds to the actual
432 * time that the device will use.
433 */
434
daqp_ns_to_timer(unsigned int * ns,int round)435 static int daqp_ns_to_timer(unsigned int *ns, int round)
436 {
437 int timer;
438
439 timer = *ns / 200;
440 *ns = timer * 200;
441
442 return timer;
443 }
444
445 /* cmdtest tests a particular command to see if it is valid.
446 * Using the cmdtest ioctl, a user can create a valid cmd
447 * and then have it executed by the cmd ioctl.
448 *
449 * cmdtest returns 1,2,3,4 or 0, depending on which tests
450 * the command passes.
451 */
452
daqp_ai_cmdtest(struct comedi_device * dev,struct comedi_subdevice * s,struct comedi_cmd * cmd)453 static int daqp_ai_cmdtest(struct comedi_device *dev,
454 struct comedi_subdevice *s, struct comedi_cmd *cmd)
455 {
456 int err = 0;
457 int tmp;
458
459 /* step 1: make sure trigger sources are trivially valid */
460
461 tmp = cmd->start_src;
462 cmd->start_src &= TRIG_NOW;
463 if (!cmd->start_src || tmp != cmd->start_src)
464 err++;
465
466 tmp = cmd->scan_begin_src;
467 cmd->scan_begin_src &= TRIG_TIMER | TRIG_FOLLOW;
468 if (!cmd->scan_begin_src || tmp != cmd->scan_begin_src)
469 err++;
470
471 tmp = cmd->convert_src;
472 cmd->convert_src &= TRIG_TIMER | TRIG_NOW;
473 if (!cmd->convert_src || tmp != cmd->convert_src)
474 err++;
475
476 tmp = cmd->scan_end_src;
477 cmd->scan_end_src &= TRIG_COUNT;
478 if (!cmd->scan_end_src || tmp != cmd->scan_end_src)
479 err++;
480
481 tmp = cmd->stop_src;
482 cmd->stop_src &= TRIG_COUNT | TRIG_NONE;
483 if (!cmd->stop_src || tmp != cmd->stop_src)
484 err++;
485
486 if (err)
487 return 1;
488
489 /*
490 * step 2: make sure trigger sources
491 * are unique and mutually compatible
492 */
493
494 /* note that mutual compatibility is not an issue here */
495 if (cmd->scan_begin_src != TRIG_TIMER &&
496 cmd->scan_begin_src != TRIG_FOLLOW)
497 err++;
498 if (cmd->convert_src != TRIG_NOW && cmd->convert_src != TRIG_TIMER)
499 err++;
500 if (cmd->scan_begin_src == TRIG_FOLLOW && cmd->convert_src == TRIG_NOW)
501 err++;
502 if (cmd->stop_src != TRIG_COUNT && cmd->stop_src != TRIG_NONE)
503 err++;
504
505 if (err)
506 return 2;
507
508 /* step 3: make sure arguments are trivially compatible */
509
510 if (cmd->start_arg != 0) {
511 cmd->start_arg = 0;
512 err++;
513 }
514 #define MAX_SPEED 10000 /* 100 kHz - in nanoseconds */
515
516 if (cmd->scan_begin_src == TRIG_TIMER
517 && cmd->scan_begin_arg < MAX_SPEED) {
518 cmd->scan_begin_arg = MAX_SPEED;
519 err++;
520 }
521
522 /* If both scan_begin and convert are both timer values, the only
523 * way that can make sense is if the scan time is the number of
524 * conversions times the convert time
525 */
526
527 if (cmd->scan_begin_src == TRIG_TIMER && cmd->convert_src == TRIG_TIMER
528 && cmd->scan_begin_arg != cmd->convert_arg * cmd->scan_end_arg) {
529 err++;
530 }
531
532 if (cmd->convert_src == TRIG_TIMER && cmd->convert_arg < MAX_SPEED) {
533 cmd->convert_arg = MAX_SPEED;
534 err++;
535 }
536
537 if (cmd->scan_end_arg != cmd->chanlist_len) {
538 cmd->scan_end_arg = cmd->chanlist_len;
539 err++;
540 }
541 if (cmd->stop_src == TRIG_COUNT) {
542 if (cmd->stop_arg > 0x00ffffff) {
543 cmd->stop_arg = 0x00ffffff;
544 err++;
545 }
546 } else {
547 /* TRIG_NONE */
548 if (cmd->stop_arg != 0) {
549 cmd->stop_arg = 0;
550 err++;
551 }
552 }
553
554 if (err)
555 return 3;
556
557 /* step 4: fix up any arguments */
558
559 if (cmd->scan_begin_src == TRIG_TIMER) {
560 tmp = cmd->scan_begin_arg;
561 daqp_ns_to_timer(&cmd->scan_begin_arg,
562 cmd->flags & TRIG_ROUND_MASK);
563 if (tmp != cmd->scan_begin_arg)
564 err++;
565 }
566
567 if (cmd->convert_src == TRIG_TIMER) {
568 tmp = cmd->convert_arg;
569 daqp_ns_to_timer(&cmd->convert_arg,
570 cmd->flags & TRIG_ROUND_MASK);
571 if (tmp != cmd->convert_arg)
572 err++;
573 }
574
575 if (err)
576 return 4;
577
578 return 0;
579 }
580
daqp_ai_cmd(struct comedi_device * dev,struct comedi_subdevice * s)581 static int daqp_ai_cmd(struct comedi_device *dev, struct comedi_subdevice *s)
582 {
583 struct local_info_t *local = (struct local_info_t *)s->private;
584 struct comedi_cmd *cmd = &s->async->cmd;
585 int counter;
586 int scanlist_start_on_every_entry;
587 int threshold;
588
589 int i;
590 int v;
591
592 if (local->stop)
593 return -EIO;
594
595
596 /* Stop any running conversion */
597 daqp_ai_cancel(dev, s);
598
599 outb(0, dev->iobase + DAQP_AUX);
600
601 /* Reset scan list queue */
602 outb(DAQP_COMMAND_RSTQ, dev->iobase + DAQP_COMMAND);
603
604 /* Program pacer clock
605 *
606 * There's two modes we can operate in. If convert_src is
607 * TRIG_TIMER, then convert_arg specifies the time between
608 * each conversion, so we program the pacer clock to that
609 * frequency and set the SCANLIST_START bit on every scanlist
610 * entry. Otherwise, convert_src is TRIG_NOW, which means
611 * we want the fastest possible conversions, scan_begin_src
612 * is TRIG_TIMER, and scan_begin_arg specifies the time between
613 * each scan, so we program the pacer clock to this frequency
614 * and only set the SCANLIST_START bit on the first entry.
615 */
616
617 if (cmd->convert_src == TRIG_TIMER) {
618 counter = daqp_ns_to_timer(&cmd->convert_arg,
619 cmd->flags & TRIG_ROUND_MASK);
620 outb(counter & 0xff, dev->iobase + DAQP_PACER_LOW);
621 outb((counter >> 8) & 0xff, dev->iobase + DAQP_PACER_MID);
622 outb((counter >> 16) & 0xff, dev->iobase + DAQP_PACER_HIGH);
623 scanlist_start_on_every_entry = 1;
624 } else {
625 counter = daqp_ns_to_timer(&cmd->scan_begin_arg,
626 cmd->flags & TRIG_ROUND_MASK);
627 outb(counter & 0xff, dev->iobase + DAQP_PACER_LOW);
628 outb((counter >> 8) & 0xff, dev->iobase + DAQP_PACER_MID);
629 outb((counter >> 16) & 0xff, dev->iobase + DAQP_PACER_HIGH);
630 scanlist_start_on_every_entry = 0;
631 }
632
633 /* Program scan list */
634
635 for (i = 0; i < cmd->chanlist_len; i++) {
636
637 int chanspec = cmd->chanlist[i];
638
639 /* Program one scan list entry */
640
641 v = DAQP_SCANLIST_CHANNEL(CR_CHAN(chanspec))
642 | DAQP_SCANLIST_GAIN(CR_RANGE(chanspec));
643
644 if (CR_AREF(chanspec) == AREF_DIFF)
645 v |= DAQP_SCANLIST_DIFFERENTIAL;
646
647 if (i == 0 || scanlist_start_on_every_entry)
648 v |= DAQP_SCANLIST_START;
649
650 outb(v & 0xff, dev->iobase + DAQP_SCANLIST);
651 outb(v >> 8, dev->iobase + DAQP_SCANLIST);
652 }
653
654 /* Now it's time to program the FIFO threshold, basically the
655 * number of samples the card will buffer before it interrupts
656 * the CPU.
657 *
658 * If we don't have a stop count, then use half the size of
659 * the FIFO (the manufacturer's recommendation). Consider
660 * that the FIFO can hold 2K samples (4K bytes). With the
661 * threshold set at half the FIFO size, we have a margin of
662 * error of 1024 samples. At the chip's maximum sample rate
663 * of 100,000 Hz, the CPU would have to delay interrupt
664 * service for a full 10 milliseconds in order to lose data
665 * here (as opposed to higher up in the kernel). I've never
666 * seen it happen. However, for slow sample rates it may
667 * buffer too much data and introduce too much delay for the
668 * user application.
669 *
670 * If we have a stop count, then things get more interesting.
671 * If the stop count is less than the FIFO size (actually
672 * three-quarters of the FIFO size - see below), we just use
673 * the stop count itself as the threshold, the card interrupts
674 * us when that many samples have been taken, and we kill the
675 * acquisition at that point and are done. If the stop count
676 * is larger than that, then we divide it by 2 until it's less
677 * than three quarters of the FIFO size (we always leave the
678 * top quarter of the FIFO as protection against sluggish CPU
679 * interrupt response) and use that as the threshold. So, if
680 * the stop count is 4000 samples, we divide by two twice to
681 * get 1000 samples, use that as the threshold, take four
682 * interrupts to get our 4000 samples and are done.
683 *
684 * The algorithm could be more clever. For example, if 81000
685 * samples are requested, we could set the threshold to 1500
686 * samples and take 54 interrupts to get 81000. But 54 isn't
687 * a power of two, so this algorithm won't find that option.
688 * Instead, it'll set the threshold at 1266 and take 64
689 * interrupts to get 81024 samples, of which the last 24 will
690 * be discarded... but we won't get the last interrupt until
691 * they've been collected. To find the first option, the
692 * computer could look at the prime decomposition of the
693 * sample count (81000 = 3^4 * 5^3 * 2^3) and factor it into a
694 * threshold (1500 = 3 * 5^3 * 2^2) and an interrupt count (54
695 * = 3^3 * 2). Hmmm... a one-line while loop or prime
696 * decomposition of integers... I'll leave it the way it is.
697 *
698 * I'll also note a mini-race condition before ignoring it in
699 * the code. Let's say we're taking 4000 samples, as before.
700 * After 1000 samples, we get an interrupt. But before that
701 * interrupt is completely serviced, another sample is taken
702 * and loaded into the FIFO. Since the interrupt handler
703 * empties the FIFO before returning, it will read 1001 samples.
704 * If that happens four times, we'll end up taking 4004 samples,
705 * not 4000. The interrupt handler will discard the extra four
706 * samples (by halting the acquisition with four samples still
707 * in the FIFO), but we will have to wait for them.
708 *
709 * In short, this code works pretty well, but for either of
710 * the two reasons noted, might end up waiting for a few more
711 * samples than actually requested. Shouldn't make too much
712 * of a difference.
713 */
714
715 /* Save away the number of conversions we should perform, and
716 * compute the FIFO threshold (in bytes, not samples - that's
717 * why we multiple local->count by 2 = sizeof(sample))
718 */
719
720 if (cmd->stop_src == TRIG_COUNT) {
721 local->count = cmd->stop_arg * cmd->scan_end_arg;
722 threshold = 2 * local->count;
723 while (threshold > DAQP_FIFO_SIZE * 3 / 4)
724 threshold /= 2;
725 } else {
726 local->count = -1;
727 threshold = DAQP_FIFO_SIZE / 2;
728 }
729
730 /* Reset data FIFO (see page 28 of DAQP User's Manual) */
731
732 outb(DAQP_COMMAND_RSTF, dev->iobase + DAQP_COMMAND);
733
734 /* Set FIFO threshold. First two bytes are near-empty
735 * threshold, which is unused; next two bytes are near-full
736 * threshold. We computed the number of bytes we want in the
737 * FIFO when the interrupt is generated, what the card wants
738 * is actually the number of available bytes left in the FIFO
739 * when the interrupt is to happen.
740 */
741
742 outb(0x00, dev->iobase + DAQP_FIFO);
743 outb(0x00, dev->iobase + DAQP_FIFO);
744
745 outb((DAQP_FIFO_SIZE - threshold) & 0xff, dev->iobase + DAQP_FIFO);
746 outb((DAQP_FIFO_SIZE - threshold) >> 8, dev->iobase + DAQP_FIFO);
747
748 /* Set trigger */
749
750 v = DAQP_CONTROL_TRIGGER_CONTINUOUS | DAQP_CONTROL_TRIGGER_INTERNAL
751 | DAQP_CONTROL_PACER_5MHz | DAQP_CONTROL_FIFO_INT_ENABLE;
752
753 outb(v, dev->iobase + DAQP_CONTROL);
754
755 /* Reset any pending interrupts (my card has a tendency to require
756 * require multiple reads on the status register to achieve this)
757 */
758 counter = 100;
759 while (--counter
760 && (inb(dev->iobase + DAQP_STATUS) & DAQP_STATUS_EVENTS)) ;
761 if (!counter) {
762 printk(KERN_ERR
763 "daqp: couldn't clear interrupts in status register\n");
764 return -1;
765 }
766
767 local->interrupt_mode = buffer;
768 local->dev = dev;
769 local->s = s;
770
771 /* Start conversion */
772 outb(DAQP_COMMAND_ARM | DAQP_COMMAND_FIFO_DATA,
773 dev->iobase + DAQP_COMMAND);
774
775 return 0;
776 }
777
778 /* Single-shot analog output routine */
779
daqp_ao_insn_write(struct comedi_device * dev,struct comedi_subdevice * s,struct comedi_insn * insn,unsigned int * data)780 static int daqp_ao_insn_write(struct comedi_device *dev,
781 struct comedi_subdevice *s,
782 struct comedi_insn *insn, unsigned int *data)
783 {
784 struct local_info_t *local = (struct local_info_t *)s->private;
785 int d;
786 unsigned int chan;
787
788 if (local->stop)
789 return -EIO;
790
791 chan = CR_CHAN(insn->chanspec);
792 d = data[0];
793 d &= 0x0fff;
794 d ^= 0x0800; /* Flip the sign */
795 d |= chan << 12;
796
797 /* Make sure D/A update mode is direct update */
798 outb(0, dev->iobase + DAQP_AUX);
799
800 outw(d, dev->iobase + DAQP_DA);
801
802 return 1;
803 }
804
805 /* Digital input routine */
806
daqp_di_insn_read(struct comedi_device * dev,struct comedi_subdevice * s,struct comedi_insn * insn,unsigned int * data)807 static int daqp_di_insn_read(struct comedi_device *dev,
808 struct comedi_subdevice *s,
809 struct comedi_insn *insn, unsigned int *data)
810 {
811 struct local_info_t *local = (struct local_info_t *)s->private;
812
813 if (local->stop)
814 return -EIO;
815
816 data[0] = inb(dev->iobase + DAQP_DIGITAL_IO);
817
818 return 1;
819 }
820
821 /* Digital output routine */
822
daqp_do_insn_write(struct comedi_device * dev,struct comedi_subdevice * s,struct comedi_insn * insn,unsigned int * data)823 static int daqp_do_insn_write(struct comedi_device *dev,
824 struct comedi_subdevice *s,
825 struct comedi_insn *insn, unsigned int *data)
826 {
827 struct local_info_t *local = (struct local_info_t *)s->private;
828
829 if (local->stop)
830 return -EIO;
831
832 outw(data[0] & 0xf, dev->iobase + DAQP_DIGITAL_IO);
833
834 return 1;
835 }
836
837 /* daqp_attach is called via comedi_config to attach a comedi device
838 * to a /dev/comedi*. Note that this is different from daqp_cs_attach()
839 * which is called by the pcmcia subsystem to attach the PCMCIA card
840 * when it is inserted.
841 */
842
daqp_attach(struct comedi_device * dev,struct comedi_devconfig * it)843 static int daqp_attach(struct comedi_device *dev, struct comedi_devconfig *it)
844 {
845 int ret;
846 struct local_info_t *local = dev_table[it->options[0]];
847 struct comedi_subdevice *s;
848
849 if (it->options[0] < 0 || it->options[0] >= MAX_DEV || !local) {
850 printk("comedi%d: No such daqp device %d\n",
851 dev->minor, it->options[0]);
852 return -EIO;
853 }
854
855 /* Typically brittle code that I don't completely understand,
856 * but "it works on my card". The intent is to pull the model
857 * number of the card out the PCMCIA CIS and stash it away as
858 * the COMEDI board_name. Looks like the third field in
859 * CISTPL_VERS_1 (offset 2) holds what we're looking for. If
860 * it doesn't work, who cares, just leave it as "DAQP".
861 */
862
863 strcpy(local->board_name, "DAQP");
864 dev->board_name = local->board_name;
865 if (local->link->prod_id[2]) {
866 if (strncmp(local->link->prod_id[2], "DAQP", 4) == 0) {
867 strncpy(local->board_name, local->link->prod_id[2],
868 sizeof(local->board_name));
869 }
870 }
871
872 dev->iobase = local->link->resource[0]->start;
873
874 ret = alloc_subdevices(dev, 4);
875 if (ret < 0)
876 return ret;
877
878 printk(KERN_INFO "comedi%d: attaching daqp%d (io 0x%04lx)\n",
879 dev->minor, it->options[0], dev->iobase);
880
881 s = dev->subdevices + 0;
882 dev->read_subdev = s;
883 s->private = local;
884 s->type = COMEDI_SUBD_AI;
885 s->subdev_flags = SDF_READABLE | SDF_GROUND | SDF_DIFF | SDF_CMD_READ;
886 s->n_chan = 8;
887 s->len_chanlist = 2048;
888 s->maxdata = 0xffff;
889 s->range_table = &range_daqp_ai;
890 s->insn_read = daqp_ai_insn_read;
891 s->do_cmdtest = daqp_ai_cmdtest;
892 s->do_cmd = daqp_ai_cmd;
893 s->cancel = daqp_ai_cancel;
894
895 s = dev->subdevices + 1;
896 dev->write_subdev = s;
897 s->private = local;
898 s->type = COMEDI_SUBD_AO;
899 s->subdev_flags = SDF_WRITEABLE;
900 s->n_chan = 2;
901 s->len_chanlist = 1;
902 s->maxdata = 0x0fff;
903 s->range_table = &range_daqp_ao;
904 s->insn_write = daqp_ao_insn_write;
905
906 s = dev->subdevices + 2;
907 s->private = local;
908 s->type = COMEDI_SUBD_DI;
909 s->subdev_flags = SDF_READABLE;
910 s->n_chan = 1;
911 s->len_chanlist = 1;
912 s->insn_read = daqp_di_insn_read;
913
914 s = dev->subdevices + 3;
915 s->private = local;
916 s->type = COMEDI_SUBD_DO;
917 s->subdev_flags = SDF_WRITEABLE;
918 s->n_chan = 1;
919 s->len_chanlist = 1;
920 s->insn_write = daqp_do_insn_write;
921
922 return 1;
923 }
924
925 /* daqp_detach (called from comedi_comdig) does nothing. If the PCMCIA
926 * card is removed, daqp_cs_detach() is called by the pcmcia subsystem.
927 */
928
daqp_detach(struct comedi_device * dev)929 static int daqp_detach(struct comedi_device *dev)
930 {
931 printk(KERN_INFO "comedi%d: detaching daqp\n", dev->minor);
932
933 return 0;
934 }
935
936 /*====================================================================
937
938 PCMCIA interface code
939
940 The rest of the code in this file is based on dummy_cs.c v1.24
941 from the Linux pcmcia_cs distribution v3.1.8 and is subject
942 to the following license agreement.
943
944 The remaining contents of this file are subject to the Mozilla Public
945 License Version 1.1 (the "License"); you may not use this file
946 except in compliance with the License. You may obtain a copy of
947 the License at http://www.mozilla.org/MPL/
948
949 Software distributed under the License is distributed on an "AS
950 IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
951 implied. See the License for the specific language governing
952 rights and limitations under the License.
953
954 The initial developer of the original code is David A. Hinds
955 <dhinds@pcmcia.sourceforge.org>. Portions created by David A. Hinds
956 are Copyright (C) 1999 David A. Hinds. All Rights Reserved.
957
958 Alternatively, the contents of this file may be used under the
959 terms of the GNU Public License version 2 (the "GPL"), in which
960 case the provisions of the GPL are applicable instead of the
961 above. If you wish to allow the use of your version of this file
962 only under the terms of the GPL and not to allow others to use
963 your version of this file under the MPL, indicate your decision
964 by deleting the provisions above and replace them with the notice
965 and other provisions required by the GPL. If you do not delete
966 the provisions above, a recipient may use your version of this
967 file under either the MPL or the GPL.
968
969 ======================================================================*/
970
971 static void daqp_cs_config(struct pcmcia_device *link);
972 static void daqp_cs_release(struct pcmcia_device *link);
973 static int daqp_cs_suspend(struct pcmcia_device *p_dev);
974 static int daqp_cs_resume(struct pcmcia_device *p_dev);
975
976 static int daqp_cs_attach(struct pcmcia_device *);
977 static void daqp_cs_detach(struct pcmcia_device *);
978
daqp_cs_attach(struct pcmcia_device * link)979 static int daqp_cs_attach(struct pcmcia_device *link)
980 {
981 struct local_info_t *local;
982 int i;
983
984 dev_dbg(&link->dev, "daqp_cs_attach()\n");
985
986 for (i = 0; i < MAX_DEV; i++)
987 if (dev_table[i] == NULL)
988 break;
989 if (i == MAX_DEV) {
990 printk(KERN_NOTICE "daqp_cs: no devices available\n");
991 return -ENODEV;
992 }
993
994 /* Allocate space for private device-specific data */
995 local = kzalloc(sizeof(struct local_info_t), GFP_KERNEL);
996 if (!local)
997 return -ENOMEM;
998
999 local->table_index = i;
1000 dev_table[i] = local;
1001 local->link = link;
1002 link->priv = local;
1003
1004 daqp_cs_config(link);
1005
1006 return 0;
1007 } /* daqp_cs_attach */
1008
daqp_cs_detach(struct pcmcia_device * link)1009 static void daqp_cs_detach(struct pcmcia_device *link)
1010 {
1011 struct local_info_t *dev = link->priv;
1012
1013 dev_dbg(&link->dev, "daqp_cs_detach\n");
1014
1015 dev->stop = 1;
1016 daqp_cs_release(link);
1017
1018 /* Unlink device structure, and free it */
1019 dev_table[dev->table_index] = NULL;
1020 kfree(dev);
1021
1022 } /* daqp_cs_detach */
1023
daqp_pcmcia_config_loop(struct pcmcia_device * p_dev,void * priv_data)1024 static int daqp_pcmcia_config_loop(struct pcmcia_device *p_dev, void *priv_data)
1025 {
1026 if (p_dev->config_index == 0)
1027 return -EINVAL;
1028
1029 return pcmcia_request_io(p_dev);
1030 }
1031
daqp_cs_config(struct pcmcia_device * link)1032 static void daqp_cs_config(struct pcmcia_device *link)
1033 {
1034 int ret;
1035
1036 dev_dbg(&link->dev, "daqp_cs_config\n");
1037
1038 link->config_flags |= CONF_ENABLE_IRQ | CONF_AUTO_SET_IO;
1039
1040 ret = pcmcia_loop_config(link, daqp_pcmcia_config_loop, NULL);
1041 if (ret) {
1042 dev_warn(&link->dev, "no configuration found\n");
1043 goto failed;
1044 }
1045
1046 ret = pcmcia_request_irq(link, daqp_interrupt);
1047 if (ret)
1048 goto failed;
1049
1050 ret = pcmcia_enable_device(link);
1051 if (ret)
1052 goto failed;
1053
1054 return;
1055
1056 failed:
1057 daqp_cs_release(link);
1058
1059 } /* daqp_cs_config */
1060
daqp_cs_release(struct pcmcia_device * link)1061 static void daqp_cs_release(struct pcmcia_device *link)
1062 {
1063 dev_dbg(&link->dev, "daqp_cs_release\n");
1064
1065 pcmcia_disable_device(link);
1066 } /* daqp_cs_release */
1067
daqp_cs_suspend(struct pcmcia_device * link)1068 static int daqp_cs_suspend(struct pcmcia_device *link)
1069 {
1070 struct local_info_t *local = link->priv;
1071
1072 /* Mark the device as stopped, to block IO until later */
1073 local->stop = 1;
1074 return 0;
1075 }
1076
daqp_cs_resume(struct pcmcia_device * link)1077 static int daqp_cs_resume(struct pcmcia_device *link)
1078 {
1079 struct local_info_t *local = link->priv;
1080
1081 local->stop = 0;
1082
1083 return 0;
1084 }
1085
1086 /*====================================================================*/
1087
1088 #ifdef MODULE
1089
1090 static const struct pcmcia_device_id daqp_cs_id_table[] = {
1091 PCMCIA_DEVICE_MANF_CARD(0x0137, 0x0027),
1092 PCMCIA_DEVICE_NULL
1093 };
1094
1095 MODULE_DEVICE_TABLE(pcmcia, daqp_cs_id_table);
1096 MODULE_AUTHOR("Brent Baccala <baccala@freesoft.org>");
1097 MODULE_DESCRIPTION("Comedi driver for Quatech DAQP PCMCIA data capture cards");
1098 MODULE_LICENSE("GPL");
1099
1100 static struct pcmcia_driver daqp_cs_driver = {
1101 .probe = daqp_cs_attach,
1102 .remove = daqp_cs_detach,
1103 .suspend = daqp_cs_suspend,
1104 .resume = daqp_cs_resume,
1105 .id_table = daqp_cs_id_table,
1106 .owner = THIS_MODULE,
1107 .name = "quatech_daqp_cs",
1108 };
1109
init_module(void)1110 int __init init_module(void)
1111 {
1112 pcmcia_register_driver(&daqp_cs_driver);
1113 comedi_driver_register(&driver_daqp);
1114 return 0;
1115 }
1116
cleanup_module(void)1117 void __exit cleanup_module(void)
1118 {
1119 comedi_driver_unregister(&driver_daqp);
1120 pcmcia_unregister_driver(&daqp_cs_driver);
1121 }
1122
1123 #endif
1124