1
2
3
4
5#include <linux/kernel.h>
6#include <linux/device.h>
7#include <linux/mutex.h>
8#include <linux/module.h>
9#include <linux/gpio.h>
10#include <linux/i2c.h>
11#include <linux/spi/spi.h>
12#include <linux/spi/mcp23s08.h>
13#include <linux/slab.h>
14#include <asm/byteorder.h>
15#include <linux/of.h>
16#include <linux/of_device.h>
17
18
19
20
21#define MCP_TYPE_S08 0
22#define MCP_TYPE_S17 1
23#define MCP_TYPE_008 2
24#define MCP_TYPE_017 3
25
26
27
28
29
30
31#define MCP_IODIR 0x00
32#define MCP_IPOL 0x01
33#define MCP_GPINTEN 0x02
34#define MCP_DEFVAL 0x03
35#define MCP_INTCON 0x04
36#define MCP_IOCON 0x05
37# define IOCON_SEQOP (1 << 5)
38# define IOCON_HAEN (1 << 3)
39# define IOCON_ODR (1 << 2)
40# define IOCON_INTPOL (1 << 1)
41#define MCP_GPPU 0x06
42#define MCP_INTF 0x07
43#define MCP_INTCAP 0x08
44#define MCP_GPIO 0x09
45#define MCP_OLAT 0x0a
46
47struct mcp23s08;
48
49struct mcp23s08_ops {
50 int (*read)(struct mcp23s08 *mcp, unsigned reg);
51 int (*write)(struct mcp23s08 *mcp, unsigned reg, unsigned val);
52 int (*read_regs)(struct mcp23s08 *mcp, unsigned reg,
53 u16 *vals, unsigned n);
54};
55
56struct mcp23s08 {
57 u8 addr;
58
59 u16 cache[11];
60
61 struct mutex lock;
62
63 struct gpio_chip chip;
64
65 const struct mcp23s08_ops *ops;
66 void *data;
67};
68
69
70
71
72
73
74struct mcp23s08_driver_data {
75 unsigned ngpio;
76 struct mcp23s08 *mcp[8];
77 struct mcp23s08 chip[];
78};
79
80
81
82#if IS_ENABLED(CONFIG_I2C)
83
84static int mcp23008_read(struct mcp23s08 *mcp, unsigned reg)
85{
86 return i2c_smbus_read_byte_data(mcp->data, reg);
87}
88
89static int mcp23008_write(struct mcp23s08 *mcp, unsigned reg, unsigned val)
90{
91 return i2c_smbus_write_byte_data(mcp->data, reg, val);
92}
93
94static int
95mcp23008_read_regs(struct mcp23s08 *mcp, unsigned reg, u16 *vals, unsigned n)
96{
97 while (n--) {
98 int ret = mcp23008_read(mcp, reg++);
99 if (ret < 0)
100 return ret;
101 *vals++ = ret;
102 }
103
104 return 0;
105}
106
107static int mcp23017_read(struct mcp23s08 *mcp, unsigned reg)
108{
109 return i2c_smbus_read_word_data(mcp->data, reg << 1);
110}
111
112static int mcp23017_write(struct mcp23s08 *mcp, unsigned reg, unsigned val)
113{
114 return i2c_smbus_write_word_data(mcp->data, reg << 1, val);
115}
116
117static int
118mcp23017_read_regs(struct mcp23s08 *mcp, unsigned reg, u16 *vals, unsigned n)
119{
120 while (n--) {
121 int ret = mcp23017_read(mcp, reg++);
122 if (ret < 0)
123 return ret;
124 *vals++ = ret;
125 }
126
127 return 0;
128}
129
130static const struct mcp23s08_ops mcp23008_ops = {
131 .read = mcp23008_read,
132 .write = mcp23008_write,
133 .read_regs = mcp23008_read_regs,
134};
135
136static const struct mcp23s08_ops mcp23017_ops = {
137 .read = mcp23017_read,
138 .write = mcp23017_write,
139 .read_regs = mcp23017_read_regs,
140};
141
142#endif
143
144
145
146#ifdef CONFIG_SPI_MASTER
147
148static int mcp23s08_read(struct mcp23s08 *mcp, unsigned reg)
149{
150 u8 tx[2], rx[1];
151 int status;
152
153 tx[0] = mcp->addr | 0x01;
154 tx[1] = reg;
155 status = spi_write_then_read(mcp->data, tx, sizeof tx, rx, sizeof rx);
156 return (status < 0) ? status : rx[0];
157}
158
159static int mcp23s08_write(struct mcp23s08 *mcp, unsigned reg, unsigned val)
160{
161 u8 tx[3];
162
163 tx[0] = mcp->addr;
164 tx[1] = reg;
165 tx[2] = val;
166 return spi_write_then_read(mcp->data, tx, sizeof tx, NULL, 0);
167}
168
169static int
170mcp23s08_read_regs(struct mcp23s08 *mcp, unsigned reg, u16 *vals, unsigned n)
171{
172 u8 tx[2], *tmp;
173 int status;
174
175 if ((n + reg) > sizeof mcp->cache)
176 return -EINVAL;
177 tx[0] = mcp->addr | 0x01;
178 tx[1] = reg;
179
180 tmp = (u8 *)vals;
181 status = spi_write_then_read(mcp->data, tx, sizeof tx, tmp, n);
182 if (status >= 0) {
183 while (n--)
184 vals[n] = tmp[n];
185 }
186 return status;
187}
188
189static int mcp23s17_read(struct mcp23s08 *mcp, unsigned reg)
190{
191 u8 tx[2], rx[2];
192 int status;
193
194 tx[0] = mcp->addr | 0x01;
195 tx[1] = reg << 1;
196 status = spi_write_then_read(mcp->data, tx, sizeof tx, rx, sizeof rx);
197 return (status < 0) ? status : (rx[0] | (rx[1] << 8));
198}
199
200static int mcp23s17_write(struct mcp23s08 *mcp, unsigned reg, unsigned val)
201{
202 u8 tx[4];
203
204 tx[0] = mcp->addr;
205 tx[1] = reg << 1;
206 tx[2] = val;
207 tx[3] = val >> 8;
208 return spi_write_then_read(mcp->data, tx, sizeof tx, NULL, 0);
209}
210
211static int
212mcp23s17_read_regs(struct mcp23s08 *mcp, unsigned reg, u16 *vals, unsigned n)
213{
214 u8 tx[2];
215 int status;
216
217 if ((n + reg) > sizeof mcp->cache)
218 return -EINVAL;
219 tx[0] = mcp->addr | 0x01;
220 tx[1] = reg << 1;
221
222 status = spi_write_then_read(mcp->data, tx, sizeof tx,
223 (u8 *)vals, n * 2);
224 if (status >= 0) {
225 while (n--)
226 vals[n] = __le16_to_cpu((__le16)vals[n]);
227 }
228
229 return status;
230}
231
232static const struct mcp23s08_ops mcp23s08_ops = {
233 .read = mcp23s08_read,
234 .write = mcp23s08_write,
235 .read_regs = mcp23s08_read_regs,
236};
237
238static const struct mcp23s08_ops mcp23s17_ops = {
239 .read = mcp23s17_read,
240 .write = mcp23s17_write,
241 .read_regs = mcp23s17_read_regs,
242};
243
244#endif
245
246
247
248static int mcp23s08_direction_input(struct gpio_chip *chip, unsigned offset)
249{
250 struct mcp23s08 *mcp = container_of(chip, struct mcp23s08, chip);
251 int status;
252
253 mutex_lock(&mcp->lock);
254 mcp->cache[MCP_IODIR] |= (1 << offset);
255 status = mcp->ops->write(mcp, MCP_IODIR, mcp->cache[MCP_IODIR]);
256 mutex_unlock(&mcp->lock);
257 return status;
258}
259
260static int mcp23s08_get(struct gpio_chip *chip, unsigned offset)
261{
262 struct mcp23s08 *mcp = container_of(chip, struct mcp23s08, chip);
263 int status;
264
265 mutex_lock(&mcp->lock);
266
267
268 status = mcp->ops->read(mcp, MCP_GPIO);
269 if (status < 0)
270 status = 0;
271 else {
272 mcp->cache[MCP_GPIO] = status;
273 status = !!(status & (1 << offset));
274 }
275 mutex_unlock(&mcp->lock);
276 return status;
277}
278
279static int __mcp23s08_set(struct mcp23s08 *mcp, unsigned mask, int value)
280{
281 unsigned olat = mcp->cache[MCP_OLAT];
282
283 if (value)
284 olat |= mask;
285 else
286 olat &= ~mask;
287 mcp->cache[MCP_OLAT] = olat;
288 return mcp->ops->write(mcp, MCP_OLAT, olat);
289}
290
291static void mcp23s08_set(struct gpio_chip *chip, unsigned offset, int value)
292{
293 struct mcp23s08 *mcp = container_of(chip, struct mcp23s08, chip);
294 unsigned mask = 1 << offset;
295
296 mutex_lock(&mcp->lock);
297 __mcp23s08_set(mcp, mask, value);
298 mutex_unlock(&mcp->lock);
299}
300
301static int
302mcp23s08_direction_output(struct gpio_chip *chip, unsigned offset, int value)
303{
304 struct mcp23s08 *mcp = container_of(chip, struct mcp23s08, chip);
305 unsigned mask = 1 << offset;
306 int status;
307
308 mutex_lock(&mcp->lock);
309 status = __mcp23s08_set(mcp, mask, value);
310 if (status == 0) {
311 mcp->cache[MCP_IODIR] &= ~mask;
312 status = mcp->ops->write(mcp, MCP_IODIR, mcp->cache[MCP_IODIR]);
313 }
314 mutex_unlock(&mcp->lock);
315 return status;
316}
317
318
319
320#ifdef CONFIG_DEBUG_FS
321
322#include <linux/seq_file.h>
323
324
325
326
327
328static void mcp23s08_dbg_show(struct seq_file *s, struct gpio_chip *chip)
329{
330 struct mcp23s08 *mcp;
331 char bank;
332 int t;
333 unsigned mask;
334
335 mcp = container_of(chip, struct mcp23s08, chip);
336
337
338 bank = '0' + ((mcp->addr >> 1) & 0x7);
339
340 mutex_lock(&mcp->lock);
341 t = mcp->ops->read_regs(mcp, 0, mcp->cache, ARRAY_SIZE(mcp->cache));
342 if (t < 0) {
343 seq_printf(s, " I/O ERROR %d\n", t);
344 goto done;
345 }
346
347 for (t = 0, mask = 1; t < chip->ngpio; t++, mask <<= 1) {
348 const char *label;
349
350 label = gpiochip_is_requested(chip, t);
351 if (!label)
352 continue;
353
354 seq_printf(s, " gpio-%-3d P%c.%d (%-12s) %s %s %s",
355 chip->base + t, bank, t, label,
356 (mcp->cache[MCP_IODIR] & mask) ? "in " : "out",
357 (mcp->cache[MCP_GPIO] & mask) ? "hi" : "lo",
358 (mcp->cache[MCP_GPPU] & mask) ? "up" : " ");
359
360 seq_printf(s, "\n");
361 }
362done:
363 mutex_unlock(&mcp->lock);
364}
365
366#else
367#define mcp23s08_dbg_show NULL
368#endif
369
370
371
372static int mcp23s08_probe_one(struct mcp23s08 *mcp, struct device *dev,
373 void *data, unsigned addr,
374 unsigned type, unsigned base, unsigned pullups)
375{
376 int status;
377
378 mutex_init(&mcp->lock);
379
380 mcp->data = data;
381 mcp->addr = addr;
382
383 mcp->chip.direction_input = mcp23s08_direction_input;
384 mcp->chip.get = mcp23s08_get;
385 mcp->chip.direction_output = mcp23s08_direction_output;
386 mcp->chip.set = mcp23s08_set;
387 mcp->chip.dbg_show = mcp23s08_dbg_show;
388#ifdef CONFIG_OF
389 mcp->chip.of_gpio_n_cells = 2;
390 mcp->chip.of_node = dev->of_node;
391#endif
392
393 switch (type) {
394#ifdef CONFIG_SPI_MASTER
395 case MCP_TYPE_S08:
396 mcp->ops = &mcp23s08_ops;
397 mcp->chip.ngpio = 8;
398 mcp->chip.label = "mcp23s08";
399 break;
400
401 case MCP_TYPE_S17:
402 mcp->ops = &mcp23s17_ops;
403 mcp->chip.ngpio = 16;
404 mcp->chip.label = "mcp23s17";
405 break;
406#endif
407
408#if IS_ENABLED(CONFIG_I2C)
409 case MCP_TYPE_008:
410 mcp->ops = &mcp23008_ops;
411 mcp->chip.ngpio = 8;
412 mcp->chip.label = "mcp23008";
413 break;
414
415 case MCP_TYPE_017:
416 mcp->ops = &mcp23017_ops;
417 mcp->chip.ngpio = 16;
418 mcp->chip.label = "mcp23017";
419 break;
420#endif
421
422 default:
423 dev_err(dev, "invalid device type (%d)\n", type);
424 return -EINVAL;
425 }
426
427 mcp->chip.base = base;
428 mcp->chip.can_sleep = 1;
429 mcp->chip.dev = dev;
430 mcp->chip.owner = THIS_MODULE;
431
432
433
434
435 status = mcp->ops->read(mcp, MCP_IOCON);
436 if (status < 0)
437 goto fail;
438 if ((status & IOCON_SEQOP) || !(status & IOCON_HAEN)) {
439
440 status &= ~(IOCON_SEQOP | (IOCON_SEQOP << 8));
441 status |= IOCON_HAEN | (IOCON_HAEN << 8);
442 status = mcp->ops->write(mcp, MCP_IOCON, status);
443 if (status < 0)
444 goto fail;
445 }
446
447
448 status = mcp->ops->write(mcp, MCP_GPPU, pullups);
449 if (status < 0)
450 goto fail;
451
452 status = mcp->ops->read_regs(mcp, 0, mcp->cache, ARRAY_SIZE(mcp->cache));
453 if (status < 0)
454 goto fail;
455
456
457 if (mcp->cache[MCP_IPOL] != 0) {
458 mcp->cache[MCP_IPOL] = 0;
459 status = mcp->ops->write(mcp, MCP_IPOL, 0);
460 if (status < 0)
461 goto fail;
462 }
463
464
465 if (mcp->cache[MCP_GPINTEN] != 0) {
466 mcp->cache[MCP_GPINTEN] = 0;
467 status = mcp->ops->write(mcp, MCP_GPINTEN, 0);
468 if (status < 0)
469 goto fail;
470 }
471
472 status = gpiochip_add(&mcp->chip);
473fail:
474 if (status < 0)
475 dev_dbg(dev, "can't setup chip %d, --> %d\n",
476 addr, status);
477 return status;
478}
479
480
481
482#ifdef CONFIG_OF
483#ifdef CONFIG_SPI_MASTER
484static struct of_device_id mcp23s08_spi_of_match[] = {
485 {
486 .compatible = "mcp,mcp23s08", .data = (void *) MCP_TYPE_S08,
487 },
488 {
489 .compatible = "mcp,mcp23s17", .data = (void *) MCP_TYPE_S17,
490 },
491 { },
492};
493MODULE_DEVICE_TABLE(of, mcp23s08_spi_of_match);
494#endif
495
496#if IS_ENABLED(CONFIG_I2C)
497static struct of_device_id mcp23s08_i2c_of_match[] = {
498 {
499 .compatible = "mcp,mcp23008", .data = (void *) MCP_TYPE_008,
500 },
501 {
502 .compatible = "mcp,mcp23017", .data = (void *) MCP_TYPE_017,
503 },
504 { },
505};
506MODULE_DEVICE_TABLE(of, mcp23s08_i2c_of_match);
507#endif
508#endif
509
510
511#if IS_ENABLED(CONFIG_I2C)
512
513static int mcp230xx_probe(struct i2c_client *client,
514 const struct i2c_device_id *id)
515{
516 struct mcp23s08_platform_data *pdata;
517 struct mcp23s08 *mcp;
518 int status, base, pullups;
519 const struct of_device_id *match;
520
521 match = of_match_device(of_match_ptr(mcp23s08_i2c_of_match),
522 &client->dev);
523 if (match) {
524 base = -1;
525 pullups = 0;
526 } else {
527 pdata = client->dev.platform_data;
528 if (!pdata || !gpio_is_valid(pdata->base)) {
529 dev_dbg(&client->dev,
530 "invalid or missing platform data\n");
531 return -EINVAL;
532 }
533 base = pdata->base;
534 pullups = pdata->chip[0].pullups;
535 }
536
537 mcp = kzalloc(sizeof *mcp, GFP_KERNEL);
538 if (!mcp)
539 return -ENOMEM;
540
541 status = mcp23s08_probe_one(mcp, &client->dev, client, client->addr,
542 id->driver_data, base, pullups);
543 if (status)
544 goto fail;
545
546 i2c_set_clientdata(client, mcp);
547
548 return 0;
549
550fail:
551 kfree(mcp);
552
553 return status;
554}
555
556static int mcp230xx_remove(struct i2c_client *client)
557{
558 struct mcp23s08 *mcp = i2c_get_clientdata(client);
559 int status;
560
561 status = gpiochip_remove(&mcp->chip);
562 if (status == 0)
563 kfree(mcp);
564
565 return status;
566}
567
568static const struct i2c_device_id mcp230xx_id[] = {
569 { "mcp23008", MCP_TYPE_008 },
570 { "mcp23017", MCP_TYPE_017 },
571 { },
572};
573MODULE_DEVICE_TABLE(i2c, mcp230xx_id);
574
575static struct i2c_driver mcp230xx_driver = {
576 .driver = {
577 .name = "mcp230xx",
578 .owner = THIS_MODULE,
579 .of_match_table = of_match_ptr(mcp23s08_i2c_of_match),
580 },
581 .probe = mcp230xx_probe,
582 .remove = mcp230xx_remove,
583 .id_table = mcp230xx_id,
584};
585
586static int __init mcp23s08_i2c_init(void)
587{
588 return i2c_add_driver(&mcp230xx_driver);
589}
590
591static void mcp23s08_i2c_exit(void)
592{
593 i2c_del_driver(&mcp230xx_driver);
594}
595
596#else
597
598static int __init mcp23s08_i2c_init(void) { return 0; }
599static void mcp23s08_i2c_exit(void) { }
600
601#endif
602
603
604
605#ifdef CONFIG_SPI_MASTER
606
607static int mcp23s08_probe(struct spi_device *spi)
608{
609 struct mcp23s08_platform_data *pdata;
610 unsigned addr;
611 unsigned chips = 0;
612 struct mcp23s08_driver_data *data;
613 int status, type;
614 unsigned base = -1,
615 ngpio = 0,
616 pullups[ARRAY_SIZE(pdata->chip)];
617 const struct of_device_id *match;
618 u32 spi_present_mask = 0;
619
620 match = of_match_device(of_match_ptr(mcp23s08_spi_of_match), &spi->dev);
621 if (match) {
622 type = (int)match->data;
623 status = of_property_read_u32(spi->dev.of_node,
624 "mcp,spi-present-mask", &spi_present_mask);
625 if (status) {
626 dev_err(&spi->dev, "DT has no spi-present-mask\n");
627 return -ENODEV;
628 }
629 if ((spi_present_mask <= 0) || (spi_present_mask >= 256)) {
630 dev_err(&spi->dev, "invalid spi-present-mask\n");
631 return -ENODEV;
632 }
633
634 for (addr = 0; addr < ARRAY_SIZE(pdata->chip); addr++)
635 pullups[addr] = 0;
636 } else {
637 type = spi_get_device_id(spi)->driver_data;
638 pdata = spi->dev.platform_data;
639 if (!pdata || !gpio_is_valid(pdata->base)) {
640 dev_dbg(&spi->dev,
641 "invalid or missing platform data\n");
642 return -EINVAL;
643 }
644
645 for (addr = 0; addr < ARRAY_SIZE(pdata->chip); addr++) {
646 if (!pdata->chip[addr].is_present)
647 continue;
648 chips++;
649 if ((type == MCP_TYPE_S08) && (addr > 3)) {
650 dev_err(&spi->dev,
651 "mcp23s08 only supports address 0..3\n");
652 return -EINVAL;
653 }
654 spi_present_mask |= 1 << addr;
655 pullups[addr] = pdata->chip[addr].pullups;
656 }
657
658 if (!chips)
659 return -ENODEV;
660
661 base = pdata->base;
662 }
663
664 data = kzalloc(sizeof *data + chips * sizeof(struct mcp23s08),
665 GFP_KERNEL);
666 if (!data)
667 return -ENOMEM;
668 spi_set_drvdata(spi, data);
669
670 for (addr = 0; addr < ARRAY_SIZE(pdata->chip); addr++) {
671 if (!(spi_present_mask & (1 << addr)))
672 continue;
673 chips--;
674 data->mcp[addr] = &data->chip[chips];
675 status = mcp23s08_probe_one(data->mcp[addr], &spi->dev, spi,
676 0x40 | (addr << 1), type, base,
677 pullups[addr]);
678 if (status < 0)
679 goto fail;
680
681 if (base != -1)
682 base += (type == MCP_TYPE_S17) ? 16 : 8;
683 ngpio += (type == MCP_TYPE_S17) ? 16 : 8;
684 }
685 data->ngpio = ngpio;
686
687
688
689
690
691
692 return 0;
693
694fail:
695 for (addr = 0; addr < ARRAY_SIZE(data->mcp); addr++) {
696 int tmp;
697
698 if (!data->mcp[addr])
699 continue;
700 tmp = gpiochip_remove(&data->mcp[addr]->chip);
701 if (tmp < 0)
702 dev_err(&spi->dev, "%s --> %d\n", "remove", tmp);
703 }
704 kfree(data);
705 return status;
706}
707
708static int mcp23s08_remove(struct spi_device *spi)
709{
710 struct mcp23s08_driver_data *data = spi_get_drvdata(spi);
711 unsigned addr;
712 int status = 0;
713
714 for (addr = 0; addr < ARRAY_SIZE(data->mcp); addr++) {
715 int tmp;
716
717 if (!data->mcp[addr])
718 continue;
719
720 tmp = gpiochip_remove(&data->mcp[addr]->chip);
721 if (tmp < 0) {
722 dev_err(&spi->dev, "%s --> %d\n", "remove", tmp);
723 status = tmp;
724 }
725 }
726 if (status == 0)
727 kfree(data);
728 return status;
729}
730
731static const struct spi_device_id mcp23s08_ids[] = {
732 { "mcp23s08", MCP_TYPE_S08 },
733 { "mcp23s17", MCP_TYPE_S17 },
734 { },
735};
736MODULE_DEVICE_TABLE(spi, mcp23s08_ids);
737
738static struct spi_driver mcp23s08_driver = {
739 .probe = mcp23s08_probe,
740 .remove = mcp23s08_remove,
741 .id_table = mcp23s08_ids,
742 .driver = {
743 .name = "mcp23s08",
744 .owner = THIS_MODULE,
745 .of_match_table = of_match_ptr(mcp23s08_spi_of_match),
746 },
747};
748
749static int __init mcp23s08_spi_init(void)
750{
751 return spi_register_driver(&mcp23s08_driver);
752}
753
754static void mcp23s08_spi_exit(void)
755{
756 spi_unregister_driver(&mcp23s08_driver);
757}
758
759#else
760
761static int __init mcp23s08_spi_init(void) { return 0; }
762static void mcp23s08_spi_exit(void) { }
763
764#endif
765
766
767
768static int __init mcp23s08_init(void)
769{
770 int ret;
771
772 ret = mcp23s08_spi_init();
773 if (ret)
774 goto spi_fail;
775
776 ret = mcp23s08_i2c_init();
777 if (ret)
778 goto i2c_fail;
779
780 return 0;
781
782 i2c_fail:
783 mcp23s08_spi_exit();
784 spi_fail:
785 return ret;
786}
787
788
789
790subsys_initcall(mcp23s08_init);
791
792static void __exit mcp23s08_exit(void)
793{
794 mcp23s08_spi_exit();
795 mcp23s08_i2c_exit();
796}
797module_exit(mcp23s08_exit);
798
799MODULE_LICENSE("GPL");
800
