xref: /linux/drivers/comedi/drivers/pcl816.c (revision 7bb6284aa7b3c369b41e7f33fcbe193161f008e7)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * pcl816.c
4  * Comedi driver for Advantech PCL-816 cards
5  *
6  * Author:  Juan Grigera <juan@grigera.com.ar>
7  * based on pcl818 by Michal Dobes <dobes@tesnet.cz> and bits of pcl812
8  */
9 
10 /*
11  * Driver: pcl816
12  * Description: Advantech PCL-816 cards, PCL-814
13  * Devices: [Advantech] PCL-816 (pcl816), PCL-814B (pcl814b)
14  * Author: Juan Grigera <juan@grigera.com.ar>
15  * Status: works
16  * Updated: Tue,  2 Apr 2002 23:15:21 -0800
17  *
18  * PCL 816 and 814B have 16 SE/DIFF ADCs, 16 DACs, 16 DI and 16 DO.
19  * Differences are at resolution (16 vs 12 bits).
20  *
21  * The driver support AI command mode, other subdevices not written.
22  *
23  * Analog output and digital input and output are not supported.
24  *
25  * Configuration Options:
26  *   [0] - IO Base
27  *   [1] - IRQ	(0=disable, 2, 3, 4, 5, 6, 7)
28  *   [2] - DMA	(0=disable, 1, 3)
29  *   [3] - 0, 10=10MHz clock for 8254
30  *	       1= 1MHz clock for 8254
31  */
32 
33 #include <linux/module.h>
34 #include <linux/gfp.h>
35 #include <linux/delay.h>
36 #include <linux/io.h>
37 #include <linux/interrupt.h>
38 #include <linux/comedi/comedidev.h>
39 #include <linux/comedi/comedi_8254.h>
40 #include <linux/comedi/comedi_isadma.h>
41 
42 /*
43  * Register I/O map
44  */
45 #define PCL816_DO_DI_LSB_REG			0x00
46 #define PCL816_DO_DI_MSB_REG			0x01
47 #define PCL816_TIMER_BASE			0x04
48 #define PCL816_AI_LSB_REG			0x08
49 #define PCL816_AI_MSB_REG			0x09
50 #define PCL816_RANGE_REG			0x09
51 #define PCL816_CLRINT_REG			0x0a
52 #define PCL816_MUX_REG				0x0b
53 #define PCL816_MUX_SCAN(_first, _last)		(((_last) << 4) | (_first))
54 #define PCL816_CTRL_REG				0x0c
55 #define PCL816_CTRL_SOFT_TRIG			BIT(0)
56 #define PCL816_CTRL_PACER_TRIG			BIT(1)
57 #define PCL816_CTRL_EXT_TRIG			BIT(2)
58 #define PCL816_CTRL_POE				BIT(3)
59 #define PCL816_CTRL_DMAEN			BIT(4)
60 #define PCL816_CTRL_INTEN			BIT(5)
61 #define PCL816_CTRL_DMASRC_SLOT(x)		(((x) & 0x3) << 6)
62 #define PCL816_STATUS_REG			0x0d
63 #define PCL816_STATUS_NEXT_CHAN_MASK		(0xf << 0)
64 #define PCL816_STATUS_INTSRC_SLOT(x)		(((x) & 0x3) << 4)
65 #define PCL816_STATUS_INTSRC_DMA		PCL816_STATUS_INTSRC_SLOT(3)
66 #define PCL816_STATUS_INTSRC_MASK		PCL816_STATUS_INTSRC_SLOT(3)
67 #define PCL816_STATUS_INTACT			BIT(6)
68 #define PCL816_STATUS_DRDY			BIT(7)
69 
70 #define MAGIC_DMA_WORD 0x5a5a
71 
72 static const struct comedi_lrange range_pcl816 = {
73 	8, {
74 		BIP_RANGE(10),
75 		BIP_RANGE(5),
76 		BIP_RANGE(2.5),
77 		BIP_RANGE(1.25),
78 		UNI_RANGE(10),
79 		UNI_RANGE(5),
80 		UNI_RANGE(2.5),
81 		UNI_RANGE(1.25)
82 	}
83 };
84 
85 struct pcl816_board {
86 	const char *name;
87 	int ai_maxdata;
88 	int ai_chanlist;
89 };
90 
91 static const struct pcl816_board boardtypes[] = {
92 	{
93 		.name		= "pcl816",
94 		.ai_maxdata	= 0xffff,
95 		.ai_chanlist	= 1024,
96 	}, {
97 		.name		= "pcl814b",
98 		.ai_maxdata	= 0x3fff,
99 		.ai_chanlist	= 1024,
100 	},
101 };
102 
103 struct pcl816_private {
104 	struct comedi_isadma *dma;
105 	unsigned int ai_poll_ptr;	/*  how many sampes transfer poll */
106 	unsigned int ai_cmd_running:1;
107 	unsigned int ai_cmd_canceled:1;
108 };
109 
110 static void pcl816_ai_setup_dma(struct comedi_device *dev,
111 				struct comedi_subdevice *s,
112 				unsigned int unread_samples)
113 {
114 	struct pcl816_private *devpriv = dev->private;
115 	struct comedi_isadma *dma = devpriv->dma;
116 	struct comedi_isadma_desc *desc = &dma->desc[dma->cur_dma];
117 	unsigned int max_samples = comedi_bytes_to_samples(s, desc->maxsize);
118 	unsigned int nsamples;
119 
120 	comedi_isadma_disable(dma->chan);
121 
122 	/*
123 	 * Determine dma size based on the buffer maxsize plus the number of
124 	 * unread samples and the number of samples remaining in the command.
125 	 */
126 	nsamples = comedi_nsamples_left(s, max_samples + unread_samples);
127 	if (nsamples > unread_samples) {
128 		nsamples -= unread_samples;
129 		desc->size = comedi_samples_to_bytes(s, nsamples);
130 		comedi_isadma_program(desc);
131 	}
132 }
133 
134 static void pcl816_ai_set_chan_range(struct comedi_device *dev,
135 				     unsigned int chan,
136 				     unsigned int range)
137 {
138 	outb(chan, dev->iobase + PCL816_MUX_REG);
139 	outb(range, dev->iobase + PCL816_RANGE_REG);
140 }
141 
142 static void pcl816_ai_set_chan_scan(struct comedi_device *dev,
143 				    unsigned int first_chan,
144 				    unsigned int last_chan)
145 {
146 	outb(PCL816_MUX_SCAN(first_chan, last_chan),
147 	     dev->iobase + PCL816_MUX_REG);
148 }
149 
150 static void pcl816_ai_setup_chanlist(struct comedi_device *dev,
151 				     unsigned int *chanlist,
152 				     unsigned int seglen)
153 {
154 	unsigned int first_chan = CR_CHAN(chanlist[0]);
155 	unsigned int last_chan;
156 	unsigned int range;
157 	unsigned int i;
158 
159 	/* store range list to card */
160 	for (i = 0; i < seglen; i++) {
161 		last_chan = CR_CHAN(chanlist[i]);
162 		range = CR_RANGE(chanlist[i]);
163 
164 		pcl816_ai_set_chan_range(dev, last_chan, range);
165 	}
166 
167 	udelay(1);
168 
169 	pcl816_ai_set_chan_scan(dev, first_chan, last_chan);
170 }
171 
172 static void pcl816_ai_clear_eoc(struct comedi_device *dev)
173 {
174 	/* writing any value clears the interrupt request */
175 	outb(0, dev->iobase + PCL816_CLRINT_REG);
176 }
177 
178 static void pcl816_ai_soft_trig(struct comedi_device *dev)
179 {
180 	/* writing any value triggers a software conversion */
181 	outb(0, dev->iobase + PCL816_AI_LSB_REG);
182 }
183 
184 static unsigned int pcl816_ai_get_sample(struct comedi_device *dev,
185 					 struct comedi_subdevice *s)
186 {
187 	unsigned int val;
188 
189 	val = inb(dev->iobase + PCL816_AI_MSB_REG) << 8;
190 	val |= inb(dev->iobase + PCL816_AI_LSB_REG);
191 
192 	return val & s->maxdata;
193 }
194 
195 static int pcl816_ai_eoc(struct comedi_device *dev,
196 			 struct comedi_subdevice *s,
197 			 struct comedi_insn *insn,
198 			 unsigned long context)
199 {
200 	unsigned int status;
201 
202 	status = inb(dev->iobase + PCL816_STATUS_REG);
203 	if ((status & PCL816_STATUS_DRDY) == 0)
204 		return 0;
205 	return -EBUSY;
206 }
207 
208 static bool pcl816_ai_next_chan(struct comedi_device *dev,
209 				struct comedi_subdevice *s)
210 {
211 	struct comedi_cmd *cmd = &s->async->cmd;
212 
213 	if (cmd->stop_src == TRIG_COUNT &&
214 	    s->async->scans_done >= cmd->stop_arg) {
215 		s->async->events |= COMEDI_CB_EOA;
216 		return false;
217 	}
218 
219 	return true;
220 }
221 
222 static void transfer_from_dma_buf(struct comedi_device *dev,
223 				  struct comedi_subdevice *s,
224 				  unsigned short *ptr,
225 				  unsigned int bufptr, unsigned int len)
226 {
227 	unsigned short val;
228 	int i;
229 
230 	for (i = 0; i < len; i++) {
231 		val = ptr[bufptr++];
232 		comedi_buf_write_samples(s, &val, 1);
233 
234 		if (!pcl816_ai_next_chan(dev, s))
235 			return;
236 	}
237 }
238 
239 static irqreturn_t pcl816_interrupt(int irq, void *d)
240 {
241 	struct comedi_device *dev = d;
242 	struct comedi_subdevice *s = dev->read_subdev;
243 	struct pcl816_private *devpriv = dev->private;
244 	struct comedi_isadma *dma = devpriv->dma;
245 	struct comedi_isadma_desc *desc;
246 	unsigned int nsamples;
247 	unsigned int bufptr;
248 
249 	if (!dev->attached || !devpriv->ai_cmd_running) {
250 		pcl816_ai_clear_eoc(dev);
251 		return IRQ_HANDLED;
252 	}
253 
254 	if (devpriv->ai_cmd_canceled) {
255 		devpriv->ai_cmd_canceled = 0;
256 		pcl816_ai_clear_eoc(dev);
257 		return IRQ_HANDLED;
258 	}
259 
260 	desc = &dma->desc[dma->cur_dma];
261 	nsamples = comedi_bytes_to_samples(s, desc->size) -
262 		   devpriv->ai_poll_ptr;
263 	bufptr = devpriv->ai_poll_ptr;
264 	devpriv->ai_poll_ptr = 0;
265 
266 	/* restart dma with the next buffer */
267 	dma->cur_dma = 1 - dma->cur_dma;
268 	pcl816_ai_setup_dma(dev, s, nsamples);
269 
270 	transfer_from_dma_buf(dev, s, desc->virt_addr, bufptr, nsamples);
271 
272 	pcl816_ai_clear_eoc(dev);
273 
274 	comedi_handle_events(dev, s);
275 	return IRQ_HANDLED;
276 }
277 
278 static int check_channel_list(struct comedi_device *dev,
279 			      struct comedi_subdevice *s,
280 			      unsigned int *chanlist,
281 			      unsigned int chanlen)
282 {
283 	unsigned int chansegment[16];
284 	unsigned int i, nowmustbechan, seglen;
285 
286 	/*  correct channel and range number check itself comedi/range.c */
287 	if (chanlen < 1) {
288 		dev_err(dev->class_dev, "range/channel list is empty!\n");
289 		return 0;
290 	}
291 
292 	if (chanlen > 1) {
293 		/*  first channel is every time ok */
294 		chansegment[0] = chanlist[0];
295 		for (i = 1, seglen = 1; i < chanlen; i++, seglen++) {
296 			/*  we detect loop, this must by finish */
297 			if (chanlist[0] == chanlist[i])
298 				break;
299 			nowmustbechan =
300 			    (CR_CHAN(chansegment[i - 1]) + 1) % chanlen;
301 			if (nowmustbechan != CR_CHAN(chanlist[i])) {
302 				/*  channel list isn't continuous :-( */
303 				dev_dbg(dev->class_dev,
304 					"channel list must be continuous! chanlist[%i]=%d but must be %d or %d!\n",
305 					i, CR_CHAN(chanlist[i]), nowmustbechan,
306 					CR_CHAN(chanlist[0]));
307 				return 0;
308 			}
309 			/*  well, this is next correct channel in list */
310 			chansegment[i] = chanlist[i];
311 		}
312 
313 		/*  check whole chanlist */
314 		for (i = 0; i < chanlen; i++) {
315 			if (chanlist[i] != chansegment[i % seglen]) {
316 				dev_dbg(dev->class_dev,
317 					"bad channel or range number! chanlist[%i]=%d,%d,%d and not %d,%d,%d!\n",
318 					i, CR_CHAN(chansegment[i]),
319 					CR_RANGE(chansegment[i]),
320 					CR_AREF(chansegment[i]),
321 					CR_CHAN(chanlist[i % seglen]),
322 					CR_RANGE(chanlist[i % seglen]),
323 					CR_AREF(chansegment[i % seglen]));
324 				return 0;	/*  chan/gain list is strange */
325 			}
326 		}
327 	} else {
328 		seglen = 1;
329 	}
330 
331 	return seglen;	/*  we can serve this with MUX logic */
332 }
333 
334 static int pcl816_ai_cmdtest(struct comedi_device *dev,
335 			     struct comedi_subdevice *s, struct comedi_cmd *cmd)
336 {
337 	int err = 0;
338 
339 	/* Step 1 : check if triggers are trivially valid */
340 
341 	err |= comedi_check_trigger_src(&cmd->start_src, TRIG_NOW);
342 	err |= comedi_check_trigger_src(&cmd->scan_begin_src, TRIG_FOLLOW);
343 	err |= comedi_check_trigger_src(&cmd->convert_src,
344 					TRIG_EXT | TRIG_TIMER);
345 	err |= comedi_check_trigger_src(&cmd->scan_end_src, TRIG_COUNT);
346 	err |= comedi_check_trigger_src(&cmd->stop_src, TRIG_COUNT | TRIG_NONE);
347 
348 	if (err)
349 		return 1;
350 
351 	/* Step 2a : make sure trigger sources are unique */
352 
353 	err |= comedi_check_trigger_is_unique(cmd->convert_src);
354 	err |= comedi_check_trigger_is_unique(cmd->stop_src);
355 
356 	/* Step 2b : and mutually compatible */
357 
358 	if (err)
359 		return 2;
360 
361 	/* Step 3: check if arguments are trivially valid */
362 
363 	err |= comedi_check_trigger_arg_is(&cmd->start_arg, 0);
364 	err |= comedi_check_trigger_arg_is(&cmd->scan_begin_arg, 0);
365 
366 	if (cmd->convert_src == TRIG_TIMER)
367 		err |= comedi_check_trigger_arg_min(&cmd->convert_arg, 10000);
368 	else	/* TRIG_EXT */
369 		err |= comedi_check_trigger_arg_is(&cmd->convert_arg, 0);
370 
371 	err |= comedi_check_trigger_arg_is(&cmd->scan_end_arg,
372 					   cmd->chanlist_len);
373 
374 	if (cmd->stop_src == TRIG_COUNT)
375 		err |= comedi_check_trigger_arg_min(&cmd->stop_arg, 1);
376 	else	/* TRIG_NONE */
377 		err |= comedi_check_trigger_arg_is(&cmd->stop_arg, 0);
378 
379 	if (err)
380 		return 3;
381 
382 	/* step 4: fix up any arguments */
383 	if (cmd->convert_src == TRIG_TIMER) {
384 		unsigned int arg = cmd->convert_arg;
385 
386 		comedi_8254_cascade_ns_to_timer(dev->pacer, &arg, cmd->flags);
387 		err |= comedi_check_trigger_arg_is(&cmd->convert_arg, arg);
388 	}
389 
390 	if (err)
391 		return 4;
392 
393 	/* step 5: complain about special chanlist considerations */
394 
395 	if (cmd->chanlist) {
396 		if (!check_channel_list(dev, s, cmd->chanlist,
397 					cmd->chanlist_len))
398 			return 5;	/*  incorrect channels list */
399 	}
400 
401 	return 0;
402 }
403 
404 static int pcl816_ai_cmd(struct comedi_device *dev, struct comedi_subdevice *s)
405 {
406 	struct pcl816_private *devpriv = dev->private;
407 	struct comedi_isadma *dma = devpriv->dma;
408 	struct comedi_cmd *cmd = &s->async->cmd;
409 	unsigned int ctrl;
410 	unsigned int seglen;
411 
412 	if (devpriv->ai_cmd_running)
413 		return -EBUSY;
414 
415 	seglen = check_channel_list(dev, s, cmd->chanlist, cmd->chanlist_len);
416 	if (seglen < 1)
417 		return -EINVAL;
418 	pcl816_ai_setup_chanlist(dev, cmd->chanlist, seglen);
419 	udelay(1);
420 
421 	devpriv->ai_cmd_running = 1;
422 	devpriv->ai_poll_ptr = 0;
423 	devpriv->ai_cmd_canceled = 0;
424 
425 	/* setup and enable dma for the first buffer */
426 	dma->cur_dma = 0;
427 	pcl816_ai_setup_dma(dev, s, 0);
428 
429 	comedi_8254_set_mode(dev->pacer, 0, I8254_MODE1 | I8254_BINARY);
430 	comedi_8254_write(dev->pacer, 0, 0x0ff);
431 	udelay(1);
432 	comedi_8254_update_divisors(dev->pacer);
433 	comedi_8254_pacer_enable(dev->pacer, 1, 2, true);
434 
435 	ctrl = PCL816_CTRL_INTEN | PCL816_CTRL_DMAEN |
436 	       PCL816_CTRL_DMASRC_SLOT(0);
437 	if (cmd->convert_src == TRIG_TIMER)
438 		ctrl |= PCL816_CTRL_PACER_TRIG;
439 	else	/* TRIG_EXT */
440 		ctrl |= PCL816_CTRL_EXT_TRIG;
441 
442 	outb(ctrl, dev->iobase + PCL816_CTRL_REG);
443 	outb((dma->chan << 4) | dev->irq,
444 	     dev->iobase + PCL816_STATUS_REG);
445 
446 	return 0;
447 }
448 
449 static int pcl816_ai_poll(struct comedi_device *dev, struct comedi_subdevice *s)
450 {
451 	struct pcl816_private *devpriv = dev->private;
452 	struct comedi_isadma *dma = devpriv->dma;
453 	struct comedi_isadma_desc *desc;
454 	unsigned long flags;
455 	unsigned int poll;
456 	int ret;
457 
458 	spin_lock_irqsave(&dev->spinlock, flags);
459 
460 	poll = comedi_isadma_poll(dma);
461 	poll = comedi_bytes_to_samples(s, poll);
462 	if (poll > devpriv->ai_poll_ptr) {
463 		desc = &dma->desc[dma->cur_dma];
464 		transfer_from_dma_buf(dev, s, desc->virt_addr,
465 				      devpriv->ai_poll_ptr,
466 				      poll - devpriv->ai_poll_ptr);
467 		/* new buffer position */
468 		devpriv->ai_poll_ptr = poll;
469 
470 		comedi_handle_events(dev, s);
471 
472 		ret = comedi_buf_n_bytes_ready(s);
473 	} else {
474 		/* no new samples */
475 		ret = 0;
476 	}
477 	spin_unlock_irqrestore(&dev->spinlock, flags);
478 
479 	return ret;
480 }
481 
482 static int pcl816_ai_cancel(struct comedi_device *dev,
483 			    struct comedi_subdevice *s)
484 {
485 	struct pcl816_private *devpriv = dev->private;
486 
487 	if (!devpriv->ai_cmd_running)
488 		return 0;
489 
490 	outb(0, dev->iobase + PCL816_CTRL_REG);
491 	pcl816_ai_clear_eoc(dev);
492 
493 	comedi_8254_pacer_enable(dev->pacer, 1, 2, false);
494 
495 	devpriv->ai_cmd_running = 0;
496 	devpriv->ai_cmd_canceled = 1;
497 
498 	return 0;
499 }
500 
501 static int pcl816_ai_insn_read(struct comedi_device *dev,
502 			       struct comedi_subdevice *s,
503 			       struct comedi_insn *insn,
504 			       unsigned int *data)
505 {
506 	unsigned int chan = CR_CHAN(insn->chanspec);
507 	unsigned int range = CR_RANGE(insn->chanspec);
508 	int ret = 0;
509 	int i;
510 
511 	outb(PCL816_CTRL_SOFT_TRIG, dev->iobase + PCL816_CTRL_REG);
512 
513 	pcl816_ai_set_chan_range(dev, chan, range);
514 	pcl816_ai_set_chan_scan(dev, chan, chan);
515 
516 	for (i = 0; i < insn->n; i++) {
517 		pcl816_ai_clear_eoc(dev);
518 		pcl816_ai_soft_trig(dev);
519 
520 		ret = comedi_timeout(dev, s, insn, pcl816_ai_eoc, 0);
521 		if (ret)
522 			break;
523 
524 		data[i] = pcl816_ai_get_sample(dev, s);
525 	}
526 	outb(0, dev->iobase + PCL816_CTRL_REG);
527 	pcl816_ai_clear_eoc(dev);
528 
529 	return ret ? ret : insn->n;
530 }
531 
532 static int pcl816_di_insn_bits(struct comedi_device *dev,
533 			       struct comedi_subdevice *s,
534 			       struct comedi_insn *insn,
535 			       unsigned int *data)
536 {
537 	data[1] = inb(dev->iobase + PCL816_DO_DI_LSB_REG) |
538 		  (inb(dev->iobase + PCL816_DO_DI_MSB_REG) << 8);
539 
540 	return insn->n;
541 }
542 
543 static int pcl816_do_insn_bits(struct comedi_device *dev,
544 			       struct comedi_subdevice *s,
545 			       struct comedi_insn *insn,
546 			       unsigned int *data)
547 {
548 	if (comedi_dio_update_state(s, data)) {
549 		outb(s->state & 0xff, dev->iobase + PCL816_DO_DI_LSB_REG);
550 		outb((s->state >> 8), dev->iobase + PCL816_DO_DI_MSB_REG);
551 	}
552 
553 	data[1] = s->state;
554 
555 	return insn->n;
556 }
557 
558 static void pcl816_reset(struct comedi_device *dev)
559 {
560 	outb(0, dev->iobase + PCL816_CTRL_REG);
561 	pcl816_ai_set_chan_range(dev, 0, 0);
562 	pcl816_ai_clear_eoc(dev);
563 
564 	/* set all digital outputs low */
565 	outb(0, dev->iobase + PCL816_DO_DI_LSB_REG);
566 	outb(0, dev->iobase + PCL816_DO_DI_MSB_REG);
567 }
568 
569 static void pcl816_alloc_irq_and_dma(struct comedi_device *dev,
570 				     struct comedi_devconfig *it)
571 {
572 	struct pcl816_private *devpriv = dev->private;
573 	unsigned int irq_num = it->options[1];
574 	unsigned int dma_chan = it->options[2];
575 
576 	/* only IRQs 2-7 and DMA channels 3 and 1 are valid */
577 	if (!(irq_num >= 2 && irq_num <= 7) ||
578 	    !(dma_chan == 3 || dma_chan == 1))
579 		return;
580 
581 	if (request_irq(irq_num, pcl816_interrupt, 0, dev->board_name, dev))
582 		return;
583 
584 	/* DMA uses two 16K buffers */
585 	devpriv->dma = comedi_isadma_alloc(dev, 2, dma_chan, dma_chan,
586 					   PAGE_SIZE * 4, COMEDI_ISADMA_READ);
587 	if (!devpriv->dma)
588 		free_irq(irq_num, dev);
589 	else
590 		dev->irq = irq_num;
591 }
592 
593 static void pcl816_free_dma(struct comedi_device *dev)
594 {
595 	struct pcl816_private *devpriv = dev->private;
596 
597 	if (devpriv)
598 		comedi_isadma_free(devpriv->dma);
599 }
600 
601 static int pcl816_attach(struct comedi_device *dev, struct comedi_devconfig *it)
602 {
603 	const struct pcl816_board *board = dev->board_ptr;
604 	struct pcl816_private *devpriv;
605 	struct comedi_subdevice *s;
606 	int ret;
607 
608 	devpriv = comedi_alloc_devpriv(dev, sizeof(*devpriv));
609 	if (!devpriv)
610 		return -ENOMEM;
611 
612 	ret = comedi_check_request_region(dev, it->options[0], 0x10,
613 					  0, 0x3ff, 16);
614 	if (ret)
615 		return ret;
616 
617 	/* an IRQ and DMA are required to support async commands */
618 	pcl816_alloc_irq_and_dma(dev, it);
619 
620 	dev->pacer = comedi_8254_io_alloc(dev->iobase + PCL816_TIMER_BASE,
621 					  I8254_OSC_BASE_10MHZ, I8254_IO8, 0);
622 	if (IS_ERR(dev->pacer))
623 		return PTR_ERR(dev->pacer);
624 
625 	ret = comedi_alloc_subdevices(dev, 4);
626 	if (ret)
627 		return ret;
628 
629 	s = &dev->subdevices[0];
630 	s->type		= COMEDI_SUBD_AI;
631 	s->subdev_flags	= SDF_CMD_READ | SDF_DIFF;
632 	s->n_chan	= 16;
633 	s->maxdata	= board->ai_maxdata;
634 	s->range_table	= &range_pcl816;
635 	s->insn_read	= pcl816_ai_insn_read;
636 	if (dev->irq) {
637 		dev->read_subdev = s;
638 		s->subdev_flags	|= SDF_CMD_READ;
639 		s->len_chanlist	= board->ai_chanlist;
640 		s->do_cmdtest	= pcl816_ai_cmdtest;
641 		s->do_cmd	= pcl816_ai_cmd;
642 		s->poll		= pcl816_ai_poll;
643 		s->cancel	= pcl816_ai_cancel;
644 	}
645 
646 	/* Piggyback Slot1 subdevice */
647 	s = &dev->subdevices[1];
648 	s->type		= COMEDI_SUBD_UNUSED;
649 
650 	/* Digital Input subdevice */
651 	s = &dev->subdevices[2];
652 	s->type		= COMEDI_SUBD_DI;
653 	s->subdev_flags	= SDF_READABLE;
654 	s->n_chan	= 16;
655 	s->maxdata	= 1;
656 	s->range_table	= &range_digital;
657 	s->insn_bits	= pcl816_di_insn_bits;
658 
659 	/* Digital Output subdevice */
660 	s = &dev->subdevices[3];
661 	s->type		= COMEDI_SUBD_DO;
662 	s->subdev_flags	= SDF_WRITABLE;
663 	s->n_chan	= 16;
664 	s->maxdata	= 1;
665 	s->range_table	= &range_digital;
666 	s->insn_bits	= pcl816_do_insn_bits;
667 
668 	pcl816_reset(dev);
669 
670 	return 0;
671 }
672 
673 static void pcl816_detach(struct comedi_device *dev)
674 {
675 	if (dev->private) {
676 		pcl816_ai_cancel(dev, dev->read_subdev);
677 		pcl816_reset(dev);
678 	}
679 	pcl816_free_dma(dev);
680 	comedi_legacy_detach(dev);
681 }
682 
683 static struct comedi_driver pcl816_driver = {
684 	.driver_name	= "pcl816",
685 	.module		= THIS_MODULE,
686 	.attach		= pcl816_attach,
687 	.detach		= pcl816_detach,
688 	.board_name	= &boardtypes[0].name,
689 	.num_names	= ARRAY_SIZE(boardtypes),
690 	.offset		= sizeof(struct pcl816_board),
691 };
692 module_comedi_driver(pcl816_driver);
693 
694 MODULE_AUTHOR("Comedi https://www.comedi.org");
695 MODULE_DESCRIPTION("Comedi low-level driver");
696 MODULE_LICENSE("GPL");
697