Free Electrons

Embedded Linux Experts

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
/*
 * MCP23S08 SPI/GPIO gpio expander driver
 */

#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/mutex.h>
#include <linux/module.h>
#include <linux/gpio.h>
#include <linux/i2c.h>
#include <linux/spi/spi.h>
#include <linux/spi/mcp23s08.h>
#include <linux/slab.h>
#include <asm/byteorder.h>

/**
 * MCP types supported by driver
 */
#define MCP_TYPE_S08	0
#define MCP_TYPE_S17	1
#define MCP_TYPE_008	2
#define MCP_TYPE_017	3

/* Registers are all 8 bits wide.
 *
 * The mcp23s17 has twice as many bits, and can be configured to work
 * with either 16 bit registers or with two adjacent 8 bit banks.
 */
#define MCP_IODIR	0x00		/* init/reset:  all ones */
#define MCP_IPOL	0x01
#define MCP_GPINTEN	0x02
#define MCP_DEFVAL	0x03
#define MCP_INTCON	0x04
#define MCP_IOCON	0x05
#	define IOCON_SEQOP	(1 << 5)
#	define IOCON_HAEN	(1 << 3)
#	define IOCON_ODR	(1 << 2)
#	define IOCON_INTPOL	(1 << 1)
#define MCP_GPPU	0x06
#define MCP_INTF	0x07
#define MCP_INTCAP	0x08
#define MCP_GPIO	0x09
#define MCP_OLAT	0x0a

struct mcp23s08;

struct mcp23s08_ops {
	int	(*read)(struct mcp23s08 *mcp, unsigned reg);
	int	(*write)(struct mcp23s08 *mcp, unsigned reg, unsigned val);
	int	(*read_regs)(struct mcp23s08 *mcp, unsigned reg,
			     u16 *vals, unsigned n);
};

struct mcp23s08 {
	u8			addr;

	u16			cache[11];
	/* lock protects the cached values */
	struct mutex		lock;

	struct gpio_chip	chip;

	const struct mcp23s08_ops	*ops;
	void			*data; /* ops specific data */
};

/* A given spi_device can represent up to eight mcp23sxx chips
 * sharing the same chipselect but using different addresses
 * (e.g. chips #0 and #3 might be populated, but not #1 or $2).
 * Driver data holds all the per-chip data.
 */
struct mcp23s08_driver_data {
	unsigned		ngpio;
	struct mcp23s08		*mcp[8];
	struct mcp23s08		chip[];
};

/*----------------------------------------------------------------------*/

#ifdef CONFIG_I2C

static int mcp23008_read(struct mcp23s08 *mcp, unsigned reg)
{
	return i2c_smbus_read_byte_data(mcp->data, reg);
}

static int mcp23008_write(struct mcp23s08 *mcp, unsigned reg, unsigned val)
{
	return i2c_smbus_write_byte_data(mcp->data, reg, val);
}

static int
mcp23008_read_regs(struct mcp23s08 *mcp, unsigned reg, u16 *vals, unsigned n)
{
	while (n--) {
		int ret = mcp23008_read(mcp, reg++);
		if (ret < 0)
			return ret;
		*vals++ = ret;
	}

	return 0;
}

static int mcp23017_read(struct mcp23s08 *mcp, unsigned reg)
{
	return i2c_smbus_read_word_data(mcp->data, reg << 1);
}

static int mcp23017_write(struct mcp23s08 *mcp, unsigned reg, unsigned val)
{
	return i2c_smbus_write_word_data(mcp->data, reg << 1, val);
}

static int
mcp23017_read_regs(struct mcp23s08 *mcp, unsigned reg, u16 *vals, unsigned n)
{
	while (n--) {
		int ret = mcp23017_read(mcp, reg++);
		if (ret < 0)
			return ret;
		*vals++ = ret;
	}

	return 0;
}

static const struct mcp23s08_ops mcp23008_ops = {
	.read		= mcp23008_read,
	.write		= mcp23008_write,
	.read_regs	= mcp23008_read_regs,
};

static const struct mcp23s08_ops mcp23017_ops = {
	.read		= mcp23017_read,
	.write		= mcp23017_write,
	.read_regs	= mcp23017_read_regs,
};

#endif /* CONFIG_I2C */

/*----------------------------------------------------------------------*/

#ifdef CONFIG_SPI_MASTER

static int mcp23s08_read(struct mcp23s08 *mcp, unsigned reg)
{
	u8	tx[2], rx[1];
	int	status;

	tx[0] = mcp->addr | 0x01;
	tx[1] = reg;
	status = spi_write_then_read(mcp->data, tx, sizeof tx, rx, sizeof rx);
	return (status < 0) ? status : rx[0];
}

static int mcp23s08_write(struct mcp23s08 *mcp, unsigned reg, unsigned val)
{
	u8	tx[3];

	tx[0] = mcp->addr;
	tx[1] = reg;
	tx[2] = val;
	return spi_write_then_read(mcp->data, tx, sizeof tx, NULL, 0);
}

static int
mcp23s08_read_regs(struct mcp23s08 *mcp, unsigned reg, u16 *vals, unsigned n)
{
	u8	tx[2], *tmp;
	int	status;

	if ((n + reg) > sizeof mcp->cache)
		return -EINVAL;
	tx[0] = mcp->addr | 0x01;
	tx[1] = reg;

	tmp = (u8 *)vals;
	status = spi_write_then_read(mcp->data, tx, sizeof tx, tmp, n);
	if (status >= 0) {
		while (n--)
			vals[n] = tmp[n]; /* expand to 16bit */
	}
	return status;
}

static int mcp23s17_read(struct mcp23s08 *mcp, unsigned reg)
{
	u8	tx[2], rx[2];
	int	status;

	tx[0] = mcp->addr | 0x01;
	tx[1] = reg << 1;
	status = spi_write_then_read(mcp->data, tx, sizeof tx, rx, sizeof rx);
	return (status < 0) ? status : (rx[0] | (rx[1] << 8));
}

static int mcp23s17_write(struct mcp23s08 *mcp, unsigned reg, unsigned val)
{
	u8	tx[4];

	tx[0] = mcp->addr;
	tx[1] = reg << 1;
	tx[2] = val;
	tx[3] = val >> 8;
	return spi_write_then_read(mcp->data, tx, sizeof tx, NULL, 0);
}

static int
mcp23s17_read_regs(struct mcp23s08 *mcp, unsigned reg, u16 *vals, unsigned n)
{
	u8	tx[2];
	int	status;

	if ((n + reg) > sizeof mcp->cache)
		return -EINVAL;
	tx[0] = mcp->addr | 0x01;
	tx[1] = reg << 1;

	status = spi_write_then_read(mcp->data, tx, sizeof tx,
				     (u8 *)vals, n * 2);
	if (status >= 0) {
		while (n--)
			vals[n] = __le16_to_cpu((__le16)vals[n]);
	}

	return status;
}

static const struct mcp23s08_ops mcp23s08_ops = {
	.read		= mcp23s08_read,
	.write		= mcp23s08_write,
	.read_regs	= mcp23s08_read_regs,
};

static const struct mcp23s08_ops mcp23s17_ops = {
	.read		= mcp23s17_read,
	.write		= mcp23s17_write,
	.read_regs	= mcp23s17_read_regs,
};

#endif /* CONFIG_SPI_MASTER */

/*----------------------------------------------------------------------*/

static int mcp23s08_direction_input(struct gpio_chip *chip, unsigned offset)
{
	struct mcp23s08	*mcp = container_of(chip, struct mcp23s08, chip);
	int status;

	mutex_lock(&mcp->lock);
	mcp->cache[MCP_IODIR] |= (1 << offset);
	status = mcp->ops->write(mcp, MCP_IODIR, mcp->cache[MCP_IODIR]);
	mutex_unlock(&mcp->lock);
	return status;
}

static int mcp23s08_get(struct gpio_chip *chip, unsigned offset)
{
	struct mcp23s08	*mcp = container_of(chip, struct mcp23s08, chip);
	int status;

	mutex_lock(&mcp->lock);

	/* REVISIT reading this clears any IRQ ... */
	status = mcp->ops->read(mcp, MCP_GPIO);
	if (status < 0)
		status = 0;
	else {
		mcp->cache[MCP_GPIO] = status;
		status = !!(status & (1 << offset));
	}
	mutex_unlock(&mcp->lock);
	return status;
}

static int __mcp23s08_set(struct mcp23s08 *mcp, unsigned mask, int value)
{
	unsigned olat = mcp->cache[MCP_OLAT];

	if (value)
		olat |= mask;
	else
		olat &= ~mask;
	mcp->cache[MCP_OLAT] = olat;
	return mcp->ops->write(mcp, MCP_OLAT, olat);
}

static void mcp23s08_set(struct gpio_chip *chip, unsigned offset, int value)
{
	struct mcp23s08	*mcp = container_of(chip, struct mcp23s08, chip);
	unsigned mask = 1 << offset;

	mutex_lock(&mcp->lock);
	__mcp23s08_set(mcp, mask, value);
	mutex_unlock(&mcp->lock);
}

static int
mcp23s08_direction_output(struct gpio_chip *chip, unsigned offset, int value)
{
	struct mcp23s08	*mcp = container_of(chip, struct mcp23s08, chip);
	unsigned mask = 1 << offset;
	int status;

	mutex_lock(&mcp->lock);
	status = __mcp23s08_set(mcp, mask, value);
	if (status == 0) {
		mcp->cache[MCP_IODIR] &= ~mask;
		status = mcp->ops->write(mcp, MCP_IODIR, mcp->cache[MCP_IODIR]);
	}
	mutex_unlock(&mcp->lock);
	return status;
}

/*----------------------------------------------------------------------*/

#ifdef CONFIG_DEBUG_FS

#include <linux/seq_file.h>

/*
 * This shows more info than the generic gpio dump code:
 * pullups, deglitching, open drain drive.
 */
static void mcp23s08_dbg_show(struct seq_file *s, struct gpio_chip *chip)
{
	struct mcp23s08	*mcp;
	char		bank;
	int		t;
	unsigned	mask;

	mcp = container_of(chip, struct mcp23s08, chip);

	/* NOTE: we only handle one bank for now ... */
	bank = '0' + ((mcp->addr >> 1) & 0x7);

	mutex_lock(&mcp->lock);
	t = mcp->ops->read_regs(mcp, 0, mcp->cache, ARRAY_SIZE(mcp->cache));
	if (t < 0) {
		seq_printf(s, " I/O ERROR %d\n", t);
		goto done;
	}

	for (t = 0, mask = 1; t < chip->ngpio; t++, mask <<= 1) {
		const char	*label;

		label = gpiochip_is_requested(chip, t);
		if (!label)
			continue;

		seq_printf(s, " gpio-%-3d P%c.%d (%-12s) %s %s %s",
			chip->base + t, bank, t, label,
			(mcp->cache[MCP_IODIR] & mask) ? "in " : "out",
			(mcp->cache[MCP_GPIO] & mask) ? "hi" : "lo",
			(mcp->cache[MCP_GPPU] & mask) ? "  " : "up");
		/* NOTE:  ignoring the irq-related registers */
		seq_printf(s, "\n");
	}
done:
	mutex_unlock(&mcp->lock);
}

#else
#define mcp23s08_dbg_show	NULL
#endif

/*----------------------------------------------------------------------*/

static int mcp23s08_probe_one(struct mcp23s08 *mcp, struct device *dev,
			      void *data, unsigned addr,
			      unsigned type, unsigned base, unsigned pullups)
{
	int status;

	mutex_init(&mcp->lock);

	mcp->data = data;
	mcp->addr = addr;

	mcp->chip.direction_input = mcp23s08_direction_input;
	mcp->chip.get = mcp23s08_get;
	mcp->chip.direction_output = mcp23s08_direction_output;
	mcp->chip.set = mcp23s08_set;
	mcp->chip.dbg_show = mcp23s08_dbg_show;

	switch (type) {
#ifdef CONFIG_SPI_MASTER
	case MCP_TYPE_S08:
		mcp->ops = &mcp23s08_ops;
		mcp->chip.ngpio = 8;
		mcp->chip.label = "mcp23s08";
		break;

	case MCP_TYPE_S17:
		mcp->ops = &mcp23s17_ops;
		mcp->chip.ngpio = 16;
		mcp->chip.label = "mcp23s17";
		break;
#endif /* CONFIG_SPI_MASTER */

#ifdef CONFIG_I2C
	case MCP_TYPE_008:
		mcp->ops = &mcp23008_ops;
		mcp->chip.ngpio = 8;
		mcp->chip.label = "mcp23008";
		break;

	case MCP_TYPE_017:
		mcp->ops = &mcp23017_ops;
		mcp->chip.ngpio = 16;
		mcp->chip.label = "mcp23017";
		break;
#endif /* CONFIG_I2C */

	default:
		dev_err(dev, "invalid device type (%d)\n", type);
		return -EINVAL;
	}

	mcp->chip.base = base;
	mcp->chip.can_sleep = 1;
	mcp->chip.dev = dev;
	mcp->chip.owner = THIS_MODULE;

	/* verify MCP_IOCON.SEQOP = 0, so sequential reads work,
	 * and MCP_IOCON.HAEN = 1, so we work with all chips.
	 */
	status = mcp->ops->read(mcp, MCP_IOCON);
	if (status < 0)
		goto fail;
	if ((status & IOCON_SEQOP) || !(status & IOCON_HAEN)) {
		/* mcp23s17 has IOCON twice, make sure they are in sync */
		status &= ~(IOCON_SEQOP | (IOCON_SEQOP << 8));
		status |= IOCON_HAEN | (IOCON_HAEN << 8);
		status = mcp->ops->write(mcp, MCP_IOCON, status);
		if (status < 0)
			goto fail;
	}

	/* configure ~100K pullups */
	status = mcp->ops->write(mcp, MCP_GPPU, pullups);
	if (status < 0)
		goto fail;

	status = mcp->ops->read_regs(mcp, 0, mcp->cache, ARRAY_SIZE(mcp->cache));
	if (status < 0)
		goto fail;

	/* disable inverter on input */
	if (mcp->cache[MCP_IPOL] != 0) {
		mcp->cache[MCP_IPOL] = 0;
		status = mcp->ops->write(mcp, MCP_IPOL, 0);
		if (status < 0)
			goto fail;
	}

	/* disable irqs */
	if (mcp->cache[MCP_GPINTEN] != 0) {
		mcp->cache[MCP_GPINTEN] = 0;
		status = mcp->ops->write(mcp, MCP_GPINTEN, 0);
		if (status < 0)
			goto fail;
	}

	status = gpiochip_add(&mcp->chip);
fail:
	if (status < 0)
		dev_dbg(dev, "can't setup chip %d, --> %d\n",
			addr, status);
	return status;
}

/*----------------------------------------------------------------------*/

#ifdef CONFIG_I2C

static int __devinit mcp230xx_probe(struct i2c_client *client,
				    const struct i2c_device_id *id)
{
	struct mcp23s08_platform_data *pdata;
	struct mcp23s08 *mcp;
	int status;

	pdata = client->dev.platform_data;
	if (!pdata || !gpio_is_valid(pdata->base)) {
		dev_dbg(&client->dev, "invalid or missing platform data\n");
		return -EINVAL;
	}

	mcp = kzalloc(sizeof *mcp, GFP_KERNEL);
	if (!mcp)
		return -ENOMEM;

	status = mcp23s08_probe_one(mcp, &client->dev, client, client->addr,
				    id->driver_data, pdata->base,
				    pdata->chip[0].pullups);
	if (status)
		goto fail;

	i2c_set_clientdata(client, mcp);

	return 0;

fail:
	kfree(mcp);

	return status;
}

static int __devexit mcp230xx_remove(struct i2c_client *client)
{
	struct mcp23s08 *mcp = i2c_get_clientdata(client);
	int status;

	status = gpiochip_remove(&mcp->chip);
	if (status == 0)
		kfree(mcp);

	return status;
}

static const struct i2c_device_id mcp230xx_id[] = {
	{ "mcp23008", MCP_TYPE_008 },
	{ "mcp23017", MCP_TYPE_017 },
	{ },
};
MODULE_DEVICE_TABLE(i2c, mcp230xx_id);

static struct i2c_driver mcp230xx_driver = {
	.driver = {
		.name	= "mcp230xx",
		.owner	= THIS_MODULE,
	},
	.probe		= mcp230xx_probe,
	.remove		= __devexit_p(mcp230xx_remove),
	.id_table	= mcp230xx_id,
};

static int __init mcp23s08_i2c_init(void)
{
	return i2c_add_driver(&mcp230xx_driver);
}

static void mcp23s08_i2c_exit(void)
{
	i2c_del_driver(&mcp230xx_driver);
}

#else

static int __init mcp23s08_i2c_init(void) { return 0; }
static void mcp23s08_i2c_exit(void) { }

#endif /* CONFIG_I2C */

/*----------------------------------------------------------------------*/

#ifdef CONFIG_SPI_MASTER

static int mcp23s08_probe(struct spi_device *spi)
{
	struct mcp23s08_platform_data	*pdata;
	unsigned			addr;
	unsigned			chips = 0;
	struct mcp23s08_driver_data	*data;
	int				status, type;
	unsigned			base;

	type = spi_get_device_id(spi)->driver_data;

	pdata = spi->dev.platform_data;
	if (!pdata || !gpio_is_valid(pdata->base)) {
		dev_dbg(&spi->dev, "invalid or missing platform data\n");
		return -EINVAL;
	}

	for (addr = 0; addr < ARRAY_SIZE(pdata->chip); addr++) {
		if (!pdata->chip[addr].is_present)
			continue;
		chips++;
		if ((type == MCP_TYPE_S08) && (addr > 3)) {
			dev_err(&spi->dev,
				"mcp23s08 only supports address 0..3\n");
			return -EINVAL;
		}
	}
	if (!chips)
		return -ENODEV;

	data = kzalloc(sizeof *data + chips * sizeof(struct mcp23s08),
			GFP_KERNEL);
	if (!data)
		return -ENOMEM;
	spi_set_drvdata(spi, data);

	base = pdata->base;
	for (addr = 0; addr < ARRAY_SIZE(pdata->chip); addr++) {
		if (!pdata->chip[addr].is_present)
			continue;
		chips--;
		data->mcp[addr] = &data->chip[chips];
		status = mcp23s08_probe_one(data->mcp[addr], &spi->dev, spi,
					    0x40 | (addr << 1), type, base,
					    pdata->chip[addr].pullups);
		if (status < 0)
			goto fail;

		base += (type == MCP_TYPE_S17) ? 16 : 8;
	}
	data->ngpio = base - pdata->base;

	/* NOTE:  these chips have a relatively sane IRQ framework, with
	 * per-signal masking and level/edge triggering.  It's not yet
	 * handled here...
	 */

	return 0;

fail:
	for (addr = 0; addr < ARRAY_SIZE(data->mcp); addr++) {
		int tmp;

		if (!data->mcp[addr])
			continue;
		tmp = gpiochip_remove(&data->mcp[addr]->chip);
		if (tmp < 0)
			dev_err(&spi->dev, "%s --> %d\n", "remove", tmp);
	}
	kfree(data);
	return status;
}

static int mcp23s08_remove(struct spi_device *spi)
{
	struct mcp23s08_driver_data	*data = spi_get_drvdata(spi);
	unsigned			addr;
	int				status = 0;

	for (addr = 0; addr < ARRAY_SIZE(data->mcp); addr++) {
		int tmp;

		if (!data->mcp[addr])
			continue;

		tmp = gpiochip_remove(&data->mcp[addr]->chip);
		if (tmp < 0) {
			dev_err(&spi->dev, "%s --> %d\n", "remove", tmp);
			status = tmp;
		}
	}
	if (status == 0)
		kfree(data);
	return status;
}

static const struct spi_device_id mcp23s08_ids[] = {
	{ "mcp23s08", MCP_TYPE_S08 },
	{ "mcp23s17", MCP_TYPE_S17 },
	{ },
};
MODULE_DEVICE_TABLE(spi, mcp23s08_ids);

static struct spi_driver mcp23s08_driver = {
	.probe		= mcp23s08_probe,
	.remove		= mcp23s08_remove,
	.id_table	= mcp23s08_ids,
	.driver = {
		.name	= "mcp23s08",
		.owner	= THIS_MODULE,
	},
};

static int __init mcp23s08_spi_init(void)
{
	return spi_register_driver(&mcp23s08_driver);
}

static void mcp23s08_spi_exit(void)
{
	spi_unregister_driver(&mcp23s08_driver);
}

#else

static int __init mcp23s08_spi_init(void) { return 0; }
static void mcp23s08_spi_exit(void) { }

#endif /* CONFIG_SPI_MASTER */

/*----------------------------------------------------------------------*/

static int __init mcp23s08_init(void)
{
	int ret;

	ret = mcp23s08_spi_init();
	if (ret)
		goto spi_fail;

	ret = mcp23s08_i2c_init();
	if (ret)
		goto i2c_fail;

	return 0;

 i2c_fail:
	mcp23s08_spi_exit();
 spi_fail:
	return ret;
}
/* register after spi/i2c postcore initcall and before
 * subsys initcalls that may rely on these GPIOs
 */
subsys_initcall(mcp23s08_init);

static void __exit mcp23s08_exit(void)
{
	mcp23s08_spi_exit();
	mcp23s08_i2c_exit();
}
module_exit(mcp23s08_exit);

MODULE_LICENSE("GPL");