xref: /openbmc/linux/drivers/comedi/drivers/pcmuio.c (revision f9900dd0)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * pcmuio.c
4  * Comedi driver for Winsystems PC-104 based 48/96-channel DIO boards.
5  *
6  * COMEDI - Linux Control and Measurement Device Interface
7  * Copyright (C) 2006 Calin A. Culianu <calin@ajvar.org>
8  */
9 
10 /*
11  * Driver: pcmuio
12  * Description: Winsystems PC-104 based 48/96-channel DIO boards.
13  * Devices: [Winsystems] PCM-UIO48A (pcmuio48), PCM-UIO96A (pcmuio96)
14  * Author: Calin Culianu <calin@ajvar.org>
15  * Updated: Fri, 13 Jan 2006 12:01:01 -0500
16  * Status: works
17  *
18  * A driver for the relatively straightforward-to-program PCM-UIO48A and
19  * PCM-UIO96A boards from Winsystems. These boards use either one or two
20  * (in the 96-DIO version) WS16C48 ASIC HighDensity I/O Chips (HDIO). This
21  * chip is interesting in that each I/O line is individually programmable
22  * for INPUT or OUTPUT (thus comedi_dio_config can be done on a per-channel
23  * basis). Also, each chip supports edge-triggered interrupts for the first
24  * 24 I/O lines. Of course, since the 96-channel version of the board has
25  * two ASICs, it can detect polarity changes on up to 48 I/O lines. Since
26  * this is essentially an (non-PnP) ISA board, I/O Address and IRQ selection
27  * are done through jumpers on the board. You need to pass that information
28  * to this driver as the first and second comedi_config option, respectively.
29  * Note that the 48-channel version uses 16 bytes of IO memory and the 96-
30  * channel version uses 32-bytes (in case you are worried about conflicts).
31  * The 48-channel board is split into two 24-channel comedi subdevices. The
32  * 96-channel board is split into 4 24-channel DIO subdevices.
33  *
34  * Note that IRQ support has been added, but it is untested.
35  *
36  * To use edge-detection IRQ support, pass the IRQs of both ASICS (for the
37  * 96 channel version) or just 1 ASIC (for 48-channel version). Then, use
38  * comedi_commands with TRIG_NOW. Your callback will be called each time an
39  * edge is triggered, and the data values will be two sample_t's, which
40  * should be concatenated to form one 32-bit unsigned int.  This value is
41  * the mask of channels that had edges detected from your channel list. Note
42  * that the bits positions in the mask correspond to positions in your
43  * chanlist when you specified the command and *not* channel id's!
44  *
45  * To set the polarity of the edge-detection interrupts pass a nonzero value
46  * for either CR_RANGE or CR_AREF for edge-up polarity, or a zero value for
47  * both CR_RANGE and CR_AREF if you want edge-down polarity.
48  *
49  * In the 48-channel version:
50  *
51  * On subdev 0, the first 24 channels are edge-detect channels.
52  *
53  * In the 96-channel board you have the following channels that can do edge
54  * detection:
55  *
56  * subdev 0, channels 0-24  (first 24 channels of 1st ASIC)
57  * subdev 2, channels 0-24  (first 24 channels of 2nd ASIC)
58  *
59  * Configuration Options:
60  *  [0] - I/O port base address
61  *  [1] - IRQ (for first ASIC, or first 24 channels)
62  *  [2] - IRQ (for second ASIC, pcmuio96 only - IRQ for chans 48-72
63  *             can be the same as first irq!)
64  */
65 
66 #include <linux/module.h>
67 #include <linux/interrupt.h>
68 #include <linux/comedi/comedidev.h>
69 
70 /*
71  * Register I/O map
72  *
73  * Offset    Page 0       Page 1       Page 2       Page 3
74  * ------  -----------  -----------  -----------  -----------
75  *  0x00   Port 0 I/O   Port 0 I/O   Port 0 I/O   Port 0 I/O
76  *  0x01   Port 1 I/O   Port 1 I/O   Port 1 I/O   Port 1 I/O
77  *  0x02   Port 2 I/O   Port 2 I/O   Port 2 I/O   Port 2 I/O
78  *  0x03   Port 3 I/O   Port 3 I/O   Port 3 I/O   Port 3 I/O
79  *  0x04   Port 4 I/O   Port 4 I/O   Port 4 I/O   Port 4 I/O
80  *  0x05   Port 5 I/O   Port 5 I/O   Port 5 I/O   Port 5 I/O
81  *  0x06   INT_PENDING  INT_PENDING  INT_PENDING  INT_PENDING
82  *  0x07    Page/Lock    Page/Lock    Page/Lock    Page/Lock
83  *  0x08       N/A         POL_0       ENAB_0       INT_ID0
84  *  0x09       N/A         POL_1       ENAB_1       INT_ID1
85  *  0x0a       N/A         POL_2       ENAB_2       INT_ID2
86  */
87 #define PCMUIO_PORT_REG(x)		(0x00 + (x))
88 #define PCMUIO_INT_PENDING_REG		0x06
89 #define PCMUIO_PAGE_LOCK_REG		0x07
90 #define PCMUIO_LOCK_PORT(x)		((1 << (x)) & 0x3f)
91 #define PCMUIO_PAGE(x)			(((x) & 0x3) << 6)
92 #define PCMUIO_PAGE_MASK		PCMUIO_PAGE(3)
93 #define PCMUIO_PAGE_POL			1
94 #define PCMUIO_PAGE_ENAB		2
95 #define PCMUIO_PAGE_INT_ID		3
96 #define PCMUIO_PAGE_REG(x)		(0x08 + (x))
97 
98 #define PCMUIO_ASIC_IOSIZE		0x10
99 #define PCMUIO_MAX_ASICS		2
100 
101 struct pcmuio_board {
102 	const char *name;
103 	const int num_asics;
104 };
105 
106 static const struct pcmuio_board pcmuio_boards[] = {
107 	{
108 		.name		= "pcmuio48",
109 		.num_asics	= 1,
110 	}, {
111 		.name		= "pcmuio96",
112 		.num_asics	= 2,
113 	},
114 };
115 
116 struct pcmuio_asic {
117 	spinlock_t pagelock;	/* protects the page registers */
118 	spinlock_t spinlock;	/* protects member variables */
119 	unsigned int enabled_mask;
120 	unsigned int active:1;
121 };
122 
123 struct pcmuio_private {
124 	struct pcmuio_asic asics[PCMUIO_MAX_ASICS];
125 	unsigned int irq2;
126 };
127 
128 static inline unsigned long pcmuio_asic_iobase(struct comedi_device *dev,
129 					       int asic)
130 {
131 	return dev->iobase + (asic * PCMUIO_ASIC_IOSIZE);
132 }
133 
134 static inline int pcmuio_subdevice_to_asic(struct comedi_subdevice *s)
135 {
136 	/*
137 	 * subdevice 0 and 1 are handled by the first asic
138 	 * subdevice 2 and 3 are handled by the second asic
139 	 */
140 	return s->index / 2;
141 }
142 
143 static inline int pcmuio_subdevice_to_port(struct comedi_subdevice *s)
144 {
145 	/*
146 	 * subdevice 0 and 2 use port registers 0-2
147 	 * subdevice 1 and 3 use port registers 3-5
148 	 */
149 	return (s->index % 2) ? 3 : 0;
150 }
151 
152 static void pcmuio_write(struct comedi_device *dev, unsigned int val,
153 			 int asic, int page, int port)
154 {
155 	struct pcmuio_private *devpriv = dev->private;
156 	struct pcmuio_asic *chip = &devpriv->asics[asic];
157 	unsigned long iobase = pcmuio_asic_iobase(dev, asic);
158 	unsigned long flags;
159 
160 	spin_lock_irqsave(&chip->pagelock, flags);
161 	if (page == 0) {
162 		/* Port registers are valid for any page */
163 		outb(val & 0xff, iobase + PCMUIO_PORT_REG(port + 0));
164 		outb((val >> 8) & 0xff, iobase + PCMUIO_PORT_REG(port + 1));
165 		outb((val >> 16) & 0xff, iobase + PCMUIO_PORT_REG(port + 2));
166 	} else {
167 		outb(PCMUIO_PAGE(page), iobase + PCMUIO_PAGE_LOCK_REG);
168 		outb(val & 0xff, iobase + PCMUIO_PAGE_REG(0));
169 		outb((val >> 8) & 0xff, iobase + PCMUIO_PAGE_REG(1));
170 		outb((val >> 16) & 0xff, iobase + PCMUIO_PAGE_REG(2));
171 	}
172 	spin_unlock_irqrestore(&chip->pagelock, flags);
173 }
174 
175 static unsigned int pcmuio_read(struct comedi_device *dev,
176 				int asic, int page, int port)
177 {
178 	struct pcmuio_private *devpriv = dev->private;
179 	struct pcmuio_asic *chip = &devpriv->asics[asic];
180 	unsigned long iobase = pcmuio_asic_iobase(dev, asic);
181 	unsigned long flags;
182 	unsigned int val;
183 
184 	spin_lock_irqsave(&chip->pagelock, flags);
185 	if (page == 0) {
186 		/* Port registers are valid for any page */
187 		val = inb(iobase + PCMUIO_PORT_REG(port + 0));
188 		val |= (inb(iobase + PCMUIO_PORT_REG(port + 1)) << 8);
189 		val |= (inb(iobase + PCMUIO_PORT_REG(port + 2)) << 16);
190 	} else {
191 		outb(PCMUIO_PAGE(page), iobase + PCMUIO_PAGE_LOCK_REG);
192 		val = inb(iobase + PCMUIO_PAGE_REG(0));
193 		val |= (inb(iobase + PCMUIO_PAGE_REG(1)) << 8);
194 		val |= (inb(iobase + PCMUIO_PAGE_REG(2)) << 16);
195 	}
196 	spin_unlock_irqrestore(&chip->pagelock, flags);
197 
198 	return val;
199 }
200 
201 /*
202  * Each channel can be individually programmed for input or output.
203  * Writing a '0' to a channel causes the corresponding output pin
204  * to go to a high-z state (pulled high by an external 10K resistor).
205  * This allows it to be used as an input. When used in the input mode,
206  * a read reflects the inverted state of the I/O pin, such that a
207  * high on the pin will read as a '0' in the register. Writing a '1'
208  * to a bit position causes the pin to sink current (up to 12mA),
209  * effectively pulling it low.
210  */
211 static int pcmuio_dio_insn_bits(struct comedi_device *dev,
212 				struct comedi_subdevice *s,
213 				struct comedi_insn *insn,
214 				unsigned int *data)
215 {
216 	int asic = pcmuio_subdevice_to_asic(s);
217 	int port = pcmuio_subdevice_to_port(s);
218 	unsigned int chanmask = (1 << s->n_chan) - 1;
219 	unsigned int mask;
220 	unsigned int val;
221 
222 	mask = comedi_dio_update_state(s, data);
223 	if (mask) {
224 		/*
225 		 * Outputs are inverted, invert the state and
226 		 * update the channels.
227 		 *
228 		 * The s->io_bits mask makes sure the input channels
229 		 * are '0' so that the outputs pins stay in a high
230 		 * z-state.
231 		 */
232 		val = ~s->state & chanmask;
233 		val &= s->io_bits;
234 		pcmuio_write(dev, val, asic, 0, port);
235 	}
236 
237 	/* get inverted state of the channels from the port */
238 	val = pcmuio_read(dev, asic, 0, port);
239 
240 	/* return the true state of the channels */
241 	data[1] = ~val & chanmask;
242 
243 	return insn->n;
244 }
245 
246 static int pcmuio_dio_insn_config(struct comedi_device *dev,
247 				  struct comedi_subdevice *s,
248 				  struct comedi_insn *insn,
249 				  unsigned int *data)
250 {
251 	int asic = pcmuio_subdevice_to_asic(s);
252 	int port = pcmuio_subdevice_to_port(s);
253 	int ret;
254 
255 	ret = comedi_dio_insn_config(dev, s, insn, data, 0);
256 	if (ret)
257 		return ret;
258 
259 	if (data[0] == INSN_CONFIG_DIO_INPUT)
260 		pcmuio_write(dev, s->io_bits, asic, 0, port);
261 
262 	return insn->n;
263 }
264 
265 static void pcmuio_reset(struct comedi_device *dev)
266 {
267 	const struct pcmuio_board *board = dev->board_ptr;
268 	int asic;
269 
270 	for (asic = 0; asic < board->num_asics; ++asic) {
271 		/* first, clear all the DIO port bits */
272 		pcmuio_write(dev, 0, asic, 0, 0);
273 		pcmuio_write(dev, 0, asic, 0, 3);
274 
275 		/* Next, clear all the paged registers for each page */
276 		pcmuio_write(dev, 0, asic, PCMUIO_PAGE_POL, 0);
277 		pcmuio_write(dev, 0, asic, PCMUIO_PAGE_ENAB, 0);
278 		pcmuio_write(dev, 0, asic, PCMUIO_PAGE_INT_ID, 0);
279 	}
280 }
281 
282 /* chip->spinlock is already locked */
283 static void pcmuio_stop_intr(struct comedi_device *dev,
284 			     struct comedi_subdevice *s)
285 {
286 	struct pcmuio_private *devpriv = dev->private;
287 	int asic = pcmuio_subdevice_to_asic(s);
288 	struct pcmuio_asic *chip = &devpriv->asics[asic];
289 
290 	chip->enabled_mask = 0;
291 	chip->active = 0;
292 	s->async->inttrig = NULL;
293 
294 	/* disable all intrs for this subdev.. */
295 	pcmuio_write(dev, 0, asic, PCMUIO_PAGE_ENAB, 0);
296 }
297 
298 static void pcmuio_handle_intr_subdev(struct comedi_device *dev,
299 				      struct comedi_subdevice *s,
300 				      unsigned int triggered)
301 {
302 	struct pcmuio_private *devpriv = dev->private;
303 	int asic = pcmuio_subdevice_to_asic(s);
304 	struct pcmuio_asic *chip = &devpriv->asics[asic];
305 	struct comedi_cmd *cmd = &s->async->cmd;
306 	unsigned int val = 0;
307 	unsigned long flags;
308 	unsigned int i;
309 
310 	spin_lock_irqsave(&chip->spinlock, flags);
311 
312 	if (!chip->active)
313 		goto done;
314 
315 	if (!(triggered & chip->enabled_mask))
316 		goto done;
317 
318 	for (i = 0; i < cmd->chanlist_len; i++) {
319 		unsigned int chan = CR_CHAN(cmd->chanlist[i]);
320 
321 		if (triggered & (1 << chan))
322 			val |= (1 << i);
323 	}
324 
325 	comedi_buf_write_samples(s, &val, 1);
326 
327 	if (cmd->stop_src == TRIG_COUNT &&
328 	    s->async->scans_done >= cmd->stop_arg)
329 		s->async->events |= COMEDI_CB_EOA;
330 
331 done:
332 	spin_unlock_irqrestore(&chip->spinlock, flags);
333 
334 	comedi_handle_events(dev, s);
335 }
336 
337 static int pcmuio_handle_asic_interrupt(struct comedi_device *dev, int asic)
338 {
339 	/* there are could be two asics so we can't use dev->read_subdev */
340 	struct comedi_subdevice *s = &dev->subdevices[asic * 2];
341 	unsigned long iobase = pcmuio_asic_iobase(dev, asic);
342 	unsigned int val;
343 
344 	/* are there any interrupts pending */
345 	val = inb(iobase + PCMUIO_INT_PENDING_REG) & 0x07;
346 	if (!val)
347 		return 0;
348 
349 	/* get, and clear, the pending interrupts */
350 	val = pcmuio_read(dev, asic, PCMUIO_PAGE_INT_ID, 0);
351 	pcmuio_write(dev, 0, asic, PCMUIO_PAGE_INT_ID, 0);
352 
353 	/* handle the pending interrupts */
354 	pcmuio_handle_intr_subdev(dev, s, val);
355 
356 	return 1;
357 }
358 
359 static irqreturn_t pcmuio_interrupt(int irq, void *d)
360 {
361 	struct comedi_device *dev = d;
362 	struct pcmuio_private *devpriv = dev->private;
363 	int handled = 0;
364 
365 	if (irq == dev->irq)
366 		handled += pcmuio_handle_asic_interrupt(dev, 0);
367 	if (irq == devpriv->irq2)
368 		handled += pcmuio_handle_asic_interrupt(dev, 1);
369 
370 	return handled ? IRQ_HANDLED : IRQ_NONE;
371 }
372 
373 /* chip->spinlock is already locked */
374 static void pcmuio_start_intr(struct comedi_device *dev,
375 			      struct comedi_subdevice *s)
376 {
377 	struct pcmuio_private *devpriv = dev->private;
378 	int asic = pcmuio_subdevice_to_asic(s);
379 	struct pcmuio_asic *chip = &devpriv->asics[asic];
380 	struct comedi_cmd *cmd = &s->async->cmd;
381 	unsigned int bits = 0;
382 	unsigned int pol_bits = 0;
383 	int i;
384 
385 	chip->enabled_mask = 0;
386 	chip->active = 1;
387 	if (cmd->chanlist) {
388 		for (i = 0; i < cmd->chanlist_len; i++) {
389 			unsigned int chanspec = cmd->chanlist[i];
390 			unsigned int chan = CR_CHAN(chanspec);
391 			unsigned int range = CR_RANGE(chanspec);
392 			unsigned int aref = CR_AREF(chanspec);
393 
394 			bits |= (1 << chan);
395 			pol_bits |= ((aref || range) ? 1 : 0) << chan;
396 		}
397 	}
398 	bits &= ((1 << s->n_chan) - 1);
399 	chip->enabled_mask = bits;
400 
401 	/* set pol and enab intrs for this subdev.. */
402 	pcmuio_write(dev, pol_bits, asic, PCMUIO_PAGE_POL, 0);
403 	pcmuio_write(dev, bits, asic, PCMUIO_PAGE_ENAB, 0);
404 }
405 
406 static int pcmuio_cancel(struct comedi_device *dev, struct comedi_subdevice *s)
407 {
408 	struct pcmuio_private *devpriv = dev->private;
409 	int asic = pcmuio_subdevice_to_asic(s);
410 	struct pcmuio_asic *chip = &devpriv->asics[asic];
411 	unsigned long flags;
412 
413 	spin_lock_irqsave(&chip->spinlock, flags);
414 	if (chip->active)
415 		pcmuio_stop_intr(dev, s);
416 	spin_unlock_irqrestore(&chip->spinlock, flags);
417 
418 	return 0;
419 }
420 
421 static int pcmuio_inttrig_start_intr(struct comedi_device *dev,
422 				     struct comedi_subdevice *s,
423 				     unsigned int trig_num)
424 {
425 	struct pcmuio_private *devpriv = dev->private;
426 	struct comedi_cmd *cmd = &s->async->cmd;
427 	int asic = pcmuio_subdevice_to_asic(s);
428 	struct pcmuio_asic *chip = &devpriv->asics[asic];
429 	unsigned long flags;
430 
431 	if (trig_num != cmd->start_arg)
432 		return -EINVAL;
433 
434 	spin_lock_irqsave(&chip->spinlock, flags);
435 	s->async->inttrig = NULL;
436 	if (chip->active)
437 		pcmuio_start_intr(dev, s);
438 
439 	spin_unlock_irqrestore(&chip->spinlock, flags);
440 
441 	return 1;
442 }
443 
444 /*
445  * 'do_cmd' function for an 'INTERRUPT' subdevice.
446  */
447 static int pcmuio_cmd(struct comedi_device *dev, struct comedi_subdevice *s)
448 {
449 	struct pcmuio_private *devpriv = dev->private;
450 	struct comedi_cmd *cmd = &s->async->cmd;
451 	int asic = pcmuio_subdevice_to_asic(s);
452 	struct pcmuio_asic *chip = &devpriv->asics[asic];
453 	unsigned long flags;
454 
455 	spin_lock_irqsave(&chip->spinlock, flags);
456 	chip->active = 1;
457 
458 	/* Set up start of acquisition. */
459 	if (cmd->start_src == TRIG_INT)
460 		s->async->inttrig = pcmuio_inttrig_start_intr;
461 	else	/* TRIG_NOW */
462 		pcmuio_start_intr(dev, s);
463 
464 	spin_unlock_irqrestore(&chip->spinlock, flags);
465 
466 	return 0;
467 }
468 
469 static int pcmuio_cmdtest(struct comedi_device *dev,
470 			  struct comedi_subdevice *s,
471 			  struct comedi_cmd *cmd)
472 {
473 	int err = 0;
474 
475 	/* Step 1 : check if triggers are trivially valid */
476 
477 	err |= comedi_check_trigger_src(&cmd->start_src, TRIG_NOW | TRIG_INT);
478 	err |= comedi_check_trigger_src(&cmd->scan_begin_src, TRIG_EXT);
479 	err |= comedi_check_trigger_src(&cmd->convert_src, TRIG_NOW);
480 	err |= comedi_check_trigger_src(&cmd->scan_end_src, TRIG_COUNT);
481 	err |= comedi_check_trigger_src(&cmd->stop_src, TRIG_COUNT | TRIG_NONE);
482 
483 	if (err)
484 		return 1;
485 
486 	/* Step 2a : make sure trigger sources are unique */
487 
488 	err |= comedi_check_trigger_is_unique(cmd->start_src);
489 	err |= comedi_check_trigger_is_unique(cmd->stop_src);
490 
491 	/* Step 2b : and mutually compatible */
492 
493 	if (err)
494 		return 2;
495 
496 	/* Step 3: check if arguments are trivially valid */
497 
498 	err |= comedi_check_trigger_arg_is(&cmd->start_arg, 0);
499 	err |= comedi_check_trigger_arg_is(&cmd->scan_begin_arg, 0);
500 	err |= comedi_check_trigger_arg_is(&cmd->convert_arg, 0);
501 	err |= comedi_check_trigger_arg_is(&cmd->scan_end_arg,
502 					   cmd->chanlist_len);
503 
504 	if (cmd->stop_src == TRIG_COUNT)
505 		err |= comedi_check_trigger_arg_min(&cmd->stop_arg, 1);
506 	else	/* TRIG_NONE */
507 		err |= comedi_check_trigger_arg_is(&cmd->stop_arg, 0);
508 
509 	if (err)
510 		return 3;
511 
512 	/* step 4: fix up any arguments */
513 
514 	/* if (err) return 4; */
515 
516 	return 0;
517 }
518 
519 static int pcmuio_attach(struct comedi_device *dev, struct comedi_devconfig *it)
520 {
521 	const struct pcmuio_board *board = dev->board_ptr;
522 	struct comedi_subdevice *s;
523 	struct pcmuio_private *devpriv;
524 	int ret;
525 	int i;
526 
527 	ret = comedi_request_region(dev, it->options[0],
528 				    board->num_asics * PCMUIO_ASIC_IOSIZE);
529 	if (ret)
530 		return ret;
531 
532 	devpriv = comedi_alloc_devpriv(dev, sizeof(*devpriv));
533 	if (!devpriv)
534 		return -ENOMEM;
535 
536 	for (i = 0; i < PCMUIO_MAX_ASICS; ++i) {
537 		struct pcmuio_asic *chip = &devpriv->asics[i];
538 
539 		spin_lock_init(&chip->pagelock);
540 		spin_lock_init(&chip->spinlock);
541 	}
542 
543 	pcmuio_reset(dev);
544 
545 	if (it->options[1]) {
546 		/* request the irq for the 1st asic */
547 		ret = request_irq(it->options[1], pcmuio_interrupt, 0,
548 				  dev->board_name, dev);
549 		if (ret == 0)
550 			dev->irq = it->options[1];
551 	}
552 
553 	if (board->num_asics == 2) {
554 		if (it->options[2] == dev->irq) {
555 			/* the same irq (or none) is used by both asics */
556 			devpriv->irq2 = it->options[2];
557 		} else if (it->options[2]) {
558 			/* request the irq for the 2nd asic */
559 			ret = request_irq(it->options[2], pcmuio_interrupt, 0,
560 					  dev->board_name, dev);
561 			if (ret == 0)
562 				devpriv->irq2 = it->options[2];
563 		}
564 	}
565 
566 	ret = comedi_alloc_subdevices(dev, board->num_asics * 2);
567 	if (ret)
568 		return ret;
569 
570 	for (i = 0; i < dev->n_subdevices; ++i) {
571 		s = &dev->subdevices[i];
572 		s->type		= COMEDI_SUBD_DIO;
573 		s->subdev_flags	= SDF_READABLE | SDF_WRITABLE;
574 		s->n_chan	= 24;
575 		s->maxdata	= 1;
576 		s->range_table	= &range_digital;
577 		s->insn_bits	= pcmuio_dio_insn_bits;
578 		s->insn_config	= pcmuio_dio_insn_config;
579 
580 		/* subdevices 0 and 2 can support interrupts */
581 		if ((i == 0 && dev->irq) || (i == 2 && devpriv->irq2)) {
582 			/* setup the interrupt subdevice */
583 			dev->read_subdev = s;
584 			s->subdev_flags	|= SDF_CMD_READ | SDF_LSAMPL |
585 					   SDF_PACKED;
586 			s->len_chanlist	= s->n_chan;
587 			s->cancel	= pcmuio_cancel;
588 			s->do_cmd	= pcmuio_cmd;
589 			s->do_cmdtest	= pcmuio_cmdtest;
590 		}
591 	}
592 
593 	return 0;
594 }
595 
596 static void pcmuio_detach(struct comedi_device *dev)
597 {
598 	struct pcmuio_private *devpriv = dev->private;
599 
600 	if (devpriv) {
601 		pcmuio_reset(dev);
602 
603 		/* free the 2nd irq if used, the core will free the 1st one */
604 		if (devpriv->irq2 && devpriv->irq2 != dev->irq)
605 			free_irq(devpriv->irq2, dev);
606 	}
607 	comedi_legacy_detach(dev);
608 }
609 
610 static struct comedi_driver pcmuio_driver = {
611 	.driver_name	= "pcmuio",
612 	.module		= THIS_MODULE,
613 	.attach		= pcmuio_attach,
614 	.detach		= pcmuio_detach,
615 	.board_name	= &pcmuio_boards[0].name,
616 	.offset		= sizeof(struct pcmuio_board),
617 	.num_names	= ARRAY_SIZE(pcmuio_boards),
618 };
619 module_comedi_driver(pcmuio_driver);
620 
621 MODULE_AUTHOR("Comedi https://www.comedi.org");
622 MODULE_DESCRIPTION("Comedi low-level driver");
623 MODULE_LICENSE("GPL");
624