1 // SPDX-License-Identifier: GPL-2.0-only
2 /* MCP23S08 SPI/I2C GPIO driver */
3 
4 #include <linux/kernel.h>
5 #include <linux/device.h>
6 #include <linux/mutex.h>
7 #include <linux/module.h>
8 #include <linux/gpio/driver.h>
9 #include <linux/i2c.h>
10 #include <linux/spi/spi.h>
11 #include <linux/spi/mcp23s08.h>
12 #include <linux/slab.h>
13 #include <asm/byteorder.h>
14 #include <linux/interrupt.h>
15 #include <linux/of_device.h>
16 #include <linux/regmap.h>
17 #include <linux/pinctrl/pinctrl.h>
18 #include <linux/pinctrl/pinconf.h>
19 #include <linux/pinctrl/pinconf-generic.h>
20 
21 /*
22  * MCP types supported by driver
23  */
24 #define MCP_TYPE_S08	0
25 #define MCP_TYPE_S17	1
26 #define MCP_TYPE_008	2
27 #define MCP_TYPE_017	3
28 #define MCP_TYPE_S18    4
29 #define MCP_TYPE_018    5
30 
31 #define MCP_MAX_DEV_PER_CS	8
32 
33 /* Registers are all 8 bits wide.
34  *
35  * The mcp23s17 has twice as many bits, and can be configured to work
36  * with either 16 bit registers or with two adjacent 8 bit banks.
37  */
38 #define MCP_IODIR	0x00		/* init/reset:  all ones */
39 #define MCP_IPOL	0x01
40 #define MCP_GPINTEN	0x02
41 #define MCP_DEFVAL	0x03
42 #define MCP_INTCON	0x04
43 #define MCP_IOCON	0x05
44 #	define IOCON_MIRROR	(1 << 6)
45 #	define IOCON_SEQOP	(1 << 5)
46 #	define IOCON_HAEN	(1 << 3)
47 #	define IOCON_ODR	(1 << 2)
48 #	define IOCON_INTPOL	(1 << 1)
49 #	define IOCON_INTCC	(1)
50 #define MCP_GPPU	0x06
51 #define MCP_INTF	0x07
52 #define MCP_INTCAP	0x08
53 #define MCP_GPIO	0x09
54 #define MCP_OLAT	0x0a
55 
56 struct mcp23s08;
57 
58 struct mcp23s08 {
59 	u8			addr;
60 	bool			irq_active_high;
61 	bool			reg_shift;
62 
63 	u16			irq_rise;
64 	u16			irq_fall;
65 	int			irq;
66 	bool			irq_controller;
67 	int			cached_gpio;
68 	/* lock protects regmap access with bypass/cache flags */
69 	struct mutex		lock;
70 
71 	struct gpio_chip	chip;
72 	struct irq_chip		irq_chip;
73 
74 	struct regmap		*regmap;
75 	struct device		*dev;
76 
77 	struct pinctrl_dev	*pctldev;
78 	struct pinctrl_desc	pinctrl_desc;
79 };
80 
81 static const struct reg_default mcp23x08_defaults[] = {
82 	{.reg = MCP_IODIR,		.def = 0xff},
83 	{.reg = MCP_IPOL,		.def = 0x00},
84 	{.reg = MCP_GPINTEN,		.def = 0x00},
85 	{.reg = MCP_DEFVAL,		.def = 0x00},
86 	{.reg = MCP_INTCON,		.def = 0x00},
87 	{.reg = MCP_IOCON,		.def = 0x00},
88 	{.reg = MCP_GPPU,		.def = 0x00},
89 	{.reg = MCP_OLAT,		.def = 0x00},
90 };
91 
92 static const struct regmap_range mcp23x08_volatile_range = {
93 	.range_min = MCP_INTF,
94 	.range_max = MCP_GPIO,
95 };
96 
97 static const struct regmap_access_table mcp23x08_volatile_table = {
98 	.yes_ranges = &mcp23x08_volatile_range,
99 	.n_yes_ranges = 1,
100 };
101 
102 static const struct regmap_range mcp23x08_precious_range = {
103 	.range_min = MCP_GPIO,
104 	.range_max = MCP_GPIO,
105 };
106 
107 static const struct regmap_access_table mcp23x08_precious_table = {
108 	.yes_ranges = &mcp23x08_precious_range,
109 	.n_yes_ranges = 1,
110 };
111 
112 static const struct regmap_config mcp23x08_regmap = {
113 	.reg_bits = 8,
114 	.val_bits = 8,
115 
116 	.reg_stride = 1,
117 	.volatile_table = &mcp23x08_volatile_table,
118 	.precious_table = &mcp23x08_precious_table,
119 	.reg_defaults = mcp23x08_defaults,
120 	.num_reg_defaults = ARRAY_SIZE(mcp23x08_defaults),
121 	.cache_type = REGCACHE_FLAT,
122 	.max_register = MCP_OLAT,
123 };
124 
125 static const struct reg_default mcp23x16_defaults[] = {
126 	{.reg = MCP_IODIR << 1,		.def = 0xffff},
127 	{.reg = MCP_IPOL << 1,		.def = 0x0000},
128 	{.reg = MCP_GPINTEN << 1,	.def = 0x0000},
129 	{.reg = MCP_DEFVAL << 1,	.def = 0x0000},
130 	{.reg = MCP_INTCON << 1,	.def = 0x0000},
131 	{.reg = MCP_IOCON << 1,		.def = 0x0000},
132 	{.reg = MCP_GPPU << 1,		.def = 0x0000},
133 	{.reg = MCP_OLAT << 1,		.def = 0x0000},
134 };
135 
136 static const struct regmap_range mcp23x16_volatile_range = {
137 	.range_min = MCP_INTF << 1,
138 	.range_max = MCP_GPIO << 1,
139 };
140 
141 static const struct regmap_access_table mcp23x16_volatile_table = {
142 	.yes_ranges = &mcp23x16_volatile_range,
143 	.n_yes_ranges = 1,
144 };
145 
146 static const struct regmap_range mcp23x16_precious_range = {
147 	.range_min = MCP_GPIO << 1,
148 	.range_max = MCP_GPIO << 1,
149 };
150 
151 static const struct regmap_access_table mcp23x16_precious_table = {
152 	.yes_ranges = &mcp23x16_precious_range,
153 	.n_yes_ranges = 1,
154 };
155 
156 static const struct regmap_config mcp23x17_regmap = {
157 	.reg_bits = 8,
158 	.val_bits = 16,
159 
160 	.reg_stride = 2,
161 	.max_register = MCP_OLAT << 1,
162 	.volatile_table = &mcp23x16_volatile_table,
163 	.precious_table = &mcp23x16_precious_table,
164 	.reg_defaults = mcp23x16_defaults,
165 	.num_reg_defaults = ARRAY_SIZE(mcp23x16_defaults),
166 	.cache_type = REGCACHE_FLAT,
167 	.val_format_endian = REGMAP_ENDIAN_LITTLE,
168 };
169 
170 static int mcp_read(struct mcp23s08 *mcp, unsigned int reg, unsigned int *val)
171 {
172 	return regmap_read(mcp->regmap, reg << mcp->reg_shift, val);
173 }
174 
175 static int mcp_write(struct mcp23s08 *mcp, unsigned int reg, unsigned int val)
176 {
177 	return regmap_write(mcp->regmap, reg << mcp->reg_shift, val);
178 }
179 
180 static int mcp_set_mask(struct mcp23s08 *mcp, unsigned int reg,
181 		       unsigned int mask, bool enabled)
182 {
183 	u16 val  = enabled ? 0xffff : 0x0000;
184 	return regmap_update_bits(mcp->regmap, reg << mcp->reg_shift,
185 				  mask, val);
186 }
187 
188 static int mcp_set_bit(struct mcp23s08 *mcp, unsigned int reg,
189 		       unsigned int pin, bool enabled)
190 {
191 	u16 mask = BIT(pin);
192 	return mcp_set_mask(mcp, reg, mask, enabled);
193 }
194 
195 static const struct pinctrl_pin_desc mcp23x08_pins[] = {
196 	PINCTRL_PIN(0, "gpio0"),
197 	PINCTRL_PIN(1, "gpio1"),
198 	PINCTRL_PIN(2, "gpio2"),
199 	PINCTRL_PIN(3, "gpio3"),
200 	PINCTRL_PIN(4, "gpio4"),
201 	PINCTRL_PIN(5, "gpio5"),
202 	PINCTRL_PIN(6, "gpio6"),
203 	PINCTRL_PIN(7, "gpio7"),
204 };
205 
206 static const struct pinctrl_pin_desc mcp23x17_pins[] = {
207 	PINCTRL_PIN(0, "gpio0"),
208 	PINCTRL_PIN(1, "gpio1"),
209 	PINCTRL_PIN(2, "gpio2"),
210 	PINCTRL_PIN(3, "gpio3"),
211 	PINCTRL_PIN(4, "gpio4"),
212 	PINCTRL_PIN(5, "gpio5"),
213 	PINCTRL_PIN(6, "gpio6"),
214 	PINCTRL_PIN(7, "gpio7"),
215 	PINCTRL_PIN(8, "gpio8"),
216 	PINCTRL_PIN(9, "gpio9"),
217 	PINCTRL_PIN(10, "gpio10"),
218 	PINCTRL_PIN(11, "gpio11"),
219 	PINCTRL_PIN(12, "gpio12"),
220 	PINCTRL_PIN(13, "gpio13"),
221 	PINCTRL_PIN(14, "gpio14"),
222 	PINCTRL_PIN(15, "gpio15"),
223 };
224 
225 static int mcp_pinctrl_get_groups_count(struct pinctrl_dev *pctldev)
226 {
227 	return 0;
228 }
229 
230 static const char *mcp_pinctrl_get_group_name(struct pinctrl_dev *pctldev,
231 						unsigned int group)
232 {
233 	return NULL;
234 }
235 
236 static int mcp_pinctrl_get_group_pins(struct pinctrl_dev *pctldev,
237 					unsigned int group,
238 					const unsigned int **pins,
239 					unsigned int *num_pins)
240 {
241 	return -ENOTSUPP;
242 }
243 
244 static const struct pinctrl_ops mcp_pinctrl_ops = {
245 	.get_groups_count = mcp_pinctrl_get_groups_count,
246 	.get_group_name = mcp_pinctrl_get_group_name,
247 	.get_group_pins = mcp_pinctrl_get_group_pins,
248 #ifdef CONFIG_OF
249 	.dt_node_to_map = pinconf_generic_dt_node_to_map_pin,
250 	.dt_free_map = pinconf_generic_dt_free_map,
251 #endif
252 };
253 
254 static int mcp_pinconf_get(struct pinctrl_dev *pctldev, unsigned int pin,
255 			      unsigned long *config)
256 {
257 	struct mcp23s08 *mcp = pinctrl_dev_get_drvdata(pctldev);
258 	enum pin_config_param param = pinconf_to_config_param(*config);
259 	unsigned int data, status;
260 	int ret;
261 
262 	switch (param) {
263 	case PIN_CONFIG_BIAS_PULL_UP:
264 		ret = mcp_read(mcp, MCP_GPPU, &data);
265 		if (ret < 0)
266 			return ret;
267 		status = (data & BIT(pin)) ? 1 : 0;
268 		break;
269 	default:
270 		return -ENOTSUPP;
271 	}
272 
273 	*config = 0;
274 
275 	return status ? 0 : -EINVAL;
276 }
277 
278 static int mcp_pinconf_set(struct pinctrl_dev *pctldev, unsigned int pin,
279 			      unsigned long *configs, unsigned int num_configs)
280 {
281 	struct mcp23s08 *mcp = pinctrl_dev_get_drvdata(pctldev);
282 	enum pin_config_param param;
283 	u32 arg;
284 	int ret = 0;
285 	int i;
286 
287 	for (i = 0; i < num_configs; i++) {
288 		param = pinconf_to_config_param(configs[i]);
289 		arg = pinconf_to_config_argument(configs[i]);
290 
291 		switch (param) {
292 		case PIN_CONFIG_BIAS_PULL_UP:
293 			ret = mcp_set_bit(mcp, MCP_GPPU, pin, arg);
294 			break;
295 		default:
296 			dev_dbg(mcp->dev, "Invalid config param %04x\n", param);
297 			return -ENOTSUPP;
298 		}
299 	}
300 
301 	return ret;
302 }
303 
304 static const struct pinconf_ops mcp_pinconf_ops = {
305 	.pin_config_get = mcp_pinconf_get,
306 	.pin_config_set = mcp_pinconf_set,
307 	.is_generic = true,
308 };
309 
310 /*----------------------------------------------------------------------*/
311 
312 #ifdef CONFIG_SPI_MASTER
313 
314 static int mcp23sxx_spi_write(void *context, const void *data, size_t count)
315 {
316 	struct mcp23s08 *mcp = context;
317 	struct spi_device *spi = to_spi_device(mcp->dev);
318 	struct spi_message m;
319 	struct spi_transfer t[2] = { { .tx_buf = &mcp->addr, .len = 1, },
320 				     { .tx_buf = data, .len = count, }, };
321 
322 	spi_message_init(&m);
323 	spi_message_add_tail(&t[0], &m);
324 	spi_message_add_tail(&t[1], &m);
325 
326 	return spi_sync(spi, &m);
327 }
328 
329 static int mcp23sxx_spi_gather_write(void *context,
330 				const void *reg, size_t reg_size,
331 				const void *val, size_t val_size)
332 {
333 	struct mcp23s08 *mcp = context;
334 	struct spi_device *spi = to_spi_device(mcp->dev);
335 	struct spi_message m;
336 	struct spi_transfer t[3] = { { .tx_buf = &mcp->addr, .len = 1, },
337 				     { .tx_buf = reg, .len = reg_size, },
338 				     { .tx_buf = val, .len = val_size, }, };
339 
340 	spi_message_init(&m);
341 	spi_message_add_tail(&t[0], &m);
342 	spi_message_add_tail(&t[1], &m);
343 	spi_message_add_tail(&t[2], &m);
344 
345 	return spi_sync(spi, &m);
346 }
347 
348 static int mcp23sxx_spi_read(void *context, const void *reg, size_t reg_size,
349 				void *val, size_t val_size)
350 {
351 	struct mcp23s08 *mcp = context;
352 	struct spi_device *spi = to_spi_device(mcp->dev);
353 	u8 tx[2];
354 
355 	if (reg_size != 1)
356 		return -EINVAL;
357 
358 	tx[0] = mcp->addr | 0x01;
359 	tx[1] = *((u8 *) reg);
360 
361 	return spi_write_then_read(spi, tx, sizeof(tx), val, val_size);
362 }
363 
364 static const struct regmap_bus mcp23sxx_spi_regmap = {
365 	.write = mcp23sxx_spi_write,
366 	.gather_write = mcp23sxx_spi_gather_write,
367 	.read = mcp23sxx_spi_read,
368 };
369 
370 #endif /* CONFIG_SPI_MASTER */
371 
372 /*----------------------------------------------------------------------*/
373 
374 /* A given spi_device can represent up to eight mcp23sxx chips
375  * sharing the same chipselect but using different addresses
376  * (e.g. chips #0 and #3 might be populated, but not #1 or $2).
377  * Driver data holds all the per-chip data.
378  */
379 struct mcp23s08_driver_data {
380 	unsigned		ngpio;
381 	struct mcp23s08		*mcp[8];
382 	struct mcp23s08		chip[];
383 };
384 
385 
386 static int mcp23s08_direction_input(struct gpio_chip *chip, unsigned offset)
387 {
388 	struct mcp23s08	*mcp = gpiochip_get_data(chip);
389 	int status;
390 
391 	mutex_lock(&mcp->lock);
392 	status = mcp_set_bit(mcp, MCP_IODIR, offset, true);
393 	mutex_unlock(&mcp->lock);
394 
395 	return status;
396 }
397 
398 static int mcp23s08_get(struct gpio_chip *chip, unsigned offset)
399 {
400 	struct mcp23s08	*mcp = gpiochip_get_data(chip);
401 	int status, ret;
402 
403 	mutex_lock(&mcp->lock);
404 
405 	/* REVISIT reading this clears any IRQ ... */
406 	ret = mcp_read(mcp, MCP_GPIO, &status);
407 	if (ret < 0)
408 		status = 0;
409 	else {
410 		mcp->cached_gpio = status;
411 		status = !!(status & (1 << offset));
412 	}
413 
414 	mutex_unlock(&mcp->lock);
415 	return status;
416 }
417 
418 static int __mcp23s08_set(struct mcp23s08 *mcp, unsigned mask, bool value)
419 {
420 	return mcp_set_mask(mcp, MCP_OLAT, mask, value);
421 }
422 
423 static void mcp23s08_set(struct gpio_chip *chip, unsigned offset, int value)
424 {
425 	struct mcp23s08	*mcp = gpiochip_get_data(chip);
426 	unsigned mask = BIT(offset);
427 
428 	mutex_lock(&mcp->lock);
429 	__mcp23s08_set(mcp, mask, !!value);
430 	mutex_unlock(&mcp->lock);
431 }
432 
433 static int
434 mcp23s08_direction_output(struct gpio_chip *chip, unsigned offset, int value)
435 {
436 	struct mcp23s08	*mcp = gpiochip_get_data(chip);
437 	unsigned mask = BIT(offset);
438 	int status;
439 
440 	mutex_lock(&mcp->lock);
441 	status = __mcp23s08_set(mcp, mask, value);
442 	if (status == 0) {
443 		status = mcp_set_mask(mcp, MCP_IODIR, mask, false);
444 	}
445 	mutex_unlock(&mcp->lock);
446 	return status;
447 }
448 
449 /*----------------------------------------------------------------------*/
450 static irqreturn_t mcp23s08_irq(int irq, void *data)
451 {
452 	struct mcp23s08 *mcp = data;
453 	int intcap, intcon, intf, i, gpio, gpio_orig, intcap_mask, defval;
454 	unsigned int child_irq;
455 	bool intf_set, intcap_changed, gpio_bit_changed,
456 		defval_changed, gpio_set;
457 
458 	mutex_lock(&mcp->lock);
459 	if (mcp_read(mcp, MCP_INTF, &intf))
460 		goto unlock;
461 
462 	if (mcp_read(mcp, MCP_INTCAP, &intcap))
463 		goto unlock;
464 
465 	if (mcp_read(mcp, MCP_INTCON, &intcon))
466 		goto unlock;
467 
468 	if (mcp_read(mcp, MCP_DEFVAL, &defval))
469 		goto unlock;
470 
471 	/* This clears the interrupt(configurable on S18) */
472 	if (mcp_read(mcp, MCP_GPIO, &gpio))
473 		goto unlock;
474 
475 	gpio_orig = mcp->cached_gpio;
476 	mcp->cached_gpio = gpio;
477 	mutex_unlock(&mcp->lock);
478 
479 	if (intf == 0) {
480 		/* There is no interrupt pending */
481 		return IRQ_HANDLED;
482 	}
483 
484 	dev_dbg(mcp->chip.parent,
485 		"intcap 0x%04X intf 0x%04X gpio_orig 0x%04X gpio 0x%04X\n",
486 		intcap, intf, gpio_orig, gpio);
487 
488 	for (i = 0; i < mcp->chip.ngpio; i++) {
489 		/* We must check all of the inputs on the chip,
490 		 * otherwise we may not notice a change on >=2 pins.
491 		 *
492 		 * On at least the mcp23s17, INTCAP is only updated
493 		 * one byte at a time(INTCAPA and INTCAPB are
494 		 * not written to at the same time - only on a per-bank
495 		 * basis).
496 		 *
497 		 * INTF only contains the single bit that caused the
498 		 * interrupt per-bank.  On the mcp23s17, there is
499 		 * INTFA and INTFB.  If two pins are changed on the A
500 		 * side at the same time, INTF will only have one bit
501 		 * set.  If one pin on the A side and one pin on the B
502 		 * side are changed at the same time, INTF will have
503 		 * two bits set.  Thus, INTF can't be the only check
504 		 * to see if the input has changed.
505 		 */
506 
507 		intf_set = intf & BIT(i);
508 		if (i < 8 && intf_set)
509 			intcap_mask = 0x00FF;
510 		else if (i >= 8 && intf_set)
511 			intcap_mask = 0xFF00;
512 		else
513 			intcap_mask = 0x00;
514 
515 		intcap_changed = (intcap_mask &
516 			(intcap & BIT(i))) !=
517 			(intcap_mask & (BIT(i) & gpio_orig));
518 		gpio_set = BIT(i) & gpio;
519 		gpio_bit_changed = (BIT(i) & gpio_orig) !=
520 			(BIT(i) & gpio);
521 		defval_changed = (BIT(i) & intcon) &&
522 			((BIT(i) & gpio) !=
523 			(BIT(i) & defval));
524 
525 		if (((gpio_bit_changed || intcap_changed) &&
526 			(BIT(i) & mcp->irq_rise) && gpio_set) ||
527 		    ((gpio_bit_changed || intcap_changed) &&
528 			(BIT(i) & mcp->irq_fall) && !gpio_set) ||
529 		    defval_changed) {
530 			child_irq = irq_find_mapping(mcp->chip.irq.domain, i);
531 			handle_nested_irq(child_irq);
532 		}
533 	}
534 
535 	return IRQ_HANDLED;
536 
537 unlock:
538 	mutex_unlock(&mcp->lock);
539 	return IRQ_HANDLED;
540 }
541 
542 static void mcp23s08_irq_mask(struct irq_data *data)
543 {
544 	struct gpio_chip *gc = irq_data_get_irq_chip_data(data);
545 	struct mcp23s08 *mcp = gpiochip_get_data(gc);
546 	unsigned int pos = data->hwirq;
547 
548 	mcp_set_bit(mcp, MCP_GPINTEN, pos, false);
549 }
550 
551 static void mcp23s08_irq_unmask(struct irq_data *data)
552 {
553 	struct gpio_chip *gc = irq_data_get_irq_chip_data(data);
554 	struct mcp23s08 *mcp = gpiochip_get_data(gc);
555 	unsigned int pos = data->hwirq;
556 
557 	mcp_set_bit(mcp, MCP_GPINTEN, pos, true);
558 }
559 
560 static int mcp23s08_irq_set_type(struct irq_data *data, unsigned int type)
561 {
562 	struct gpio_chip *gc = irq_data_get_irq_chip_data(data);
563 	struct mcp23s08 *mcp = gpiochip_get_data(gc);
564 	unsigned int pos = data->hwirq;
565 	int status = 0;
566 
567 	if ((type & IRQ_TYPE_EDGE_BOTH) == IRQ_TYPE_EDGE_BOTH) {
568 		mcp_set_bit(mcp, MCP_INTCON, pos, false);
569 		mcp->irq_rise |= BIT(pos);
570 		mcp->irq_fall |= BIT(pos);
571 	} else if (type & IRQ_TYPE_EDGE_RISING) {
572 		mcp_set_bit(mcp, MCP_INTCON, pos, false);
573 		mcp->irq_rise |= BIT(pos);
574 		mcp->irq_fall &= ~BIT(pos);
575 	} else if (type & IRQ_TYPE_EDGE_FALLING) {
576 		mcp_set_bit(mcp, MCP_INTCON, pos, false);
577 		mcp->irq_rise &= ~BIT(pos);
578 		mcp->irq_fall |= BIT(pos);
579 	} else if (type & IRQ_TYPE_LEVEL_HIGH) {
580 		mcp_set_bit(mcp, MCP_INTCON, pos, true);
581 		mcp_set_bit(mcp, MCP_DEFVAL, pos, false);
582 	} else if (type & IRQ_TYPE_LEVEL_LOW) {
583 		mcp_set_bit(mcp, MCP_INTCON, pos, true);
584 		mcp_set_bit(mcp, MCP_DEFVAL, pos, true);
585 	} else
586 		return -EINVAL;
587 
588 	return status;
589 }
590 
591 static void mcp23s08_irq_bus_lock(struct irq_data *data)
592 {
593 	struct gpio_chip *gc = irq_data_get_irq_chip_data(data);
594 	struct mcp23s08 *mcp = gpiochip_get_data(gc);
595 
596 	mutex_lock(&mcp->lock);
597 	regcache_cache_only(mcp->regmap, true);
598 }
599 
600 static void mcp23s08_irq_bus_unlock(struct irq_data *data)
601 {
602 	struct gpio_chip *gc = irq_data_get_irq_chip_data(data);
603 	struct mcp23s08 *mcp = gpiochip_get_data(gc);
604 
605 	regcache_cache_only(mcp->regmap, false);
606 	regcache_sync(mcp->regmap);
607 
608 	mutex_unlock(&mcp->lock);
609 }
610 
611 static int mcp23s08_irq_setup(struct mcp23s08 *mcp)
612 {
613 	struct gpio_chip *chip = &mcp->chip;
614 	int err;
615 	unsigned long irqflags = IRQF_ONESHOT | IRQF_SHARED;
616 
617 	if (mcp->irq_active_high)
618 		irqflags |= IRQF_TRIGGER_HIGH;
619 	else
620 		irqflags |= IRQF_TRIGGER_LOW;
621 
622 	err = devm_request_threaded_irq(chip->parent, mcp->irq, NULL,
623 					mcp23s08_irq,
624 					irqflags, dev_name(chip->parent), mcp);
625 	if (err != 0) {
626 		dev_err(chip->parent, "unable to request IRQ#%d: %d\n",
627 			mcp->irq, err);
628 		return err;
629 	}
630 
631 	return 0;
632 }
633 
634 static int mcp23s08_irqchip_setup(struct mcp23s08 *mcp)
635 {
636 	struct gpio_chip *chip = &mcp->chip;
637 	int err;
638 
639 	err =  gpiochip_irqchip_add_nested(chip,
640 					   &mcp->irq_chip,
641 					   0,
642 					   handle_simple_irq,
643 					   IRQ_TYPE_NONE);
644 	if (err) {
645 		dev_err(chip->parent,
646 			"could not connect irqchip to gpiochip: %d\n", err);
647 		return err;
648 	}
649 
650 	gpiochip_set_nested_irqchip(chip,
651 				    &mcp->irq_chip,
652 				    mcp->irq);
653 
654 	return 0;
655 }
656 
657 /*----------------------------------------------------------------------*/
658 
659 static int mcp23s08_probe_one(struct mcp23s08 *mcp, struct device *dev,
660 			      void *data, unsigned addr, unsigned type,
661 			      unsigned int base, int cs)
662 {
663 	int status, ret;
664 	bool mirror = false;
665 	bool open_drain = false;
666 	struct regmap_config *one_regmap_config = NULL;
667 	int raw_chip_address = (addr & ~0x40) >> 1;
668 
669 	mutex_init(&mcp->lock);
670 
671 	mcp->dev = dev;
672 	mcp->addr = addr;
673 	mcp->irq_active_high = false;
674 
675 	mcp->chip.direction_input = mcp23s08_direction_input;
676 	mcp->chip.get = mcp23s08_get;
677 	mcp->chip.direction_output = mcp23s08_direction_output;
678 	mcp->chip.set = mcp23s08_set;
679 #ifdef CONFIG_OF_GPIO
680 	mcp->chip.of_gpio_n_cells = 2;
681 	mcp->chip.of_node = dev->of_node;
682 #endif
683 
684 	switch (type) {
685 #ifdef CONFIG_SPI_MASTER
686 	case MCP_TYPE_S08:
687 	case MCP_TYPE_S17:
688 		switch (type) {
689 		case MCP_TYPE_S08:
690 			one_regmap_config =
691 				devm_kmemdup(dev, &mcp23x08_regmap,
692 					sizeof(struct regmap_config), GFP_KERNEL);
693 			mcp->reg_shift = 0;
694 			mcp->chip.ngpio = 8;
695 			mcp->chip.label = devm_kasprintf(dev, GFP_KERNEL,
696 					"mcp23s08.%d", raw_chip_address);
697 			break;
698 		case MCP_TYPE_S17:
699 			one_regmap_config =
700 				devm_kmemdup(dev, &mcp23x17_regmap,
701 					sizeof(struct regmap_config), GFP_KERNEL);
702 			mcp->reg_shift = 1;
703 			mcp->chip.ngpio = 16;
704 			mcp->chip.label = devm_kasprintf(dev, GFP_KERNEL,
705 					"mcp23s17.%d", raw_chip_address);
706 			break;
707 		}
708 		if (!one_regmap_config)
709 			return -ENOMEM;
710 
711 		one_regmap_config->name = devm_kasprintf(dev, GFP_KERNEL, "%d", raw_chip_address);
712 		mcp->regmap = devm_regmap_init(dev, &mcp23sxx_spi_regmap, mcp,
713 					       one_regmap_config);
714 		break;
715 
716 	case MCP_TYPE_S18:
717 		one_regmap_config =
718 			devm_kmemdup(dev, &mcp23x17_regmap,
719 				sizeof(struct regmap_config), GFP_KERNEL);
720 		if (!one_regmap_config)
721 			return -ENOMEM;
722 		mcp->regmap = devm_regmap_init(dev, &mcp23sxx_spi_regmap, mcp,
723 					       one_regmap_config);
724 		mcp->reg_shift = 1;
725 		mcp->chip.ngpio = 16;
726 		mcp->chip.label = "mcp23s18";
727 		break;
728 #endif /* CONFIG_SPI_MASTER */
729 
730 #if IS_ENABLED(CONFIG_I2C)
731 	case MCP_TYPE_008:
732 		mcp->regmap = devm_regmap_init_i2c(data, &mcp23x08_regmap);
733 		mcp->reg_shift = 0;
734 		mcp->chip.ngpio = 8;
735 		mcp->chip.label = "mcp23008";
736 		break;
737 
738 	case MCP_TYPE_017:
739 		mcp->regmap = devm_regmap_init_i2c(data, &mcp23x17_regmap);
740 		mcp->reg_shift = 1;
741 		mcp->chip.ngpio = 16;
742 		mcp->chip.label = "mcp23017";
743 		break;
744 
745 	case MCP_TYPE_018:
746 		mcp->regmap = devm_regmap_init_i2c(data, &mcp23x17_regmap);
747 		mcp->reg_shift = 1;
748 		mcp->chip.ngpio = 16;
749 		mcp->chip.label = "mcp23018";
750 		break;
751 #endif /* CONFIG_I2C */
752 
753 	default:
754 		dev_err(dev, "invalid device type (%d)\n", type);
755 		return -EINVAL;
756 	}
757 
758 	if (IS_ERR(mcp->regmap))
759 		return PTR_ERR(mcp->regmap);
760 
761 	mcp->chip.base = base;
762 	mcp->chip.can_sleep = true;
763 	mcp->chip.parent = dev;
764 	mcp->chip.owner = THIS_MODULE;
765 
766 	/* verify MCP_IOCON.SEQOP = 0, so sequential reads work,
767 	 * and MCP_IOCON.HAEN = 1, so we work with all chips.
768 	 */
769 
770 	ret = mcp_read(mcp, MCP_IOCON, &status);
771 	if (ret < 0)
772 		goto fail;
773 
774 	ret = devm_gpiochip_add_data(dev, &mcp->chip, mcp);
775 	if (ret < 0)
776 		goto fail;
777 
778 	mcp->irq_controller =
779 		device_property_read_bool(dev, "interrupt-controller");
780 	if (mcp->irq && mcp->irq_controller) {
781 		mcp->irq_active_high =
782 			device_property_read_bool(dev,
783 					      "microchip,irq-active-high");
784 
785 		mirror = device_property_read_bool(dev, "microchip,irq-mirror");
786 		open_drain = device_property_read_bool(dev, "drive-open-drain");
787 	}
788 
789 	if ((status & IOCON_SEQOP) || !(status & IOCON_HAEN) || mirror ||
790 	     mcp->irq_active_high || open_drain) {
791 		/* mcp23s17 has IOCON twice, make sure they are in sync */
792 		status &= ~(IOCON_SEQOP | (IOCON_SEQOP << 8));
793 		status |= IOCON_HAEN | (IOCON_HAEN << 8);
794 		if (mcp->irq_active_high)
795 			status |= IOCON_INTPOL | (IOCON_INTPOL << 8);
796 		else
797 			status &= ~(IOCON_INTPOL | (IOCON_INTPOL << 8));
798 
799 		if (mirror)
800 			status |= IOCON_MIRROR | (IOCON_MIRROR << 8);
801 
802 		if (open_drain)
803 			status |= IOCON_ODR | (IOCON_ODR << 8);
804 
805 		if (type == MCP_TYPE_S18 || type == MCP_TYPE_018)
806 			status |= IOCON_INTCC | (IOCON_INTCC << 8);
807 
808 		ret = mcp_write(mcp, MCP_IOCON, status);
809 		if (ret < 0)
810 			goto fail;
811 	}
812 
813 	if (mcp->irq && mcp->irq_controller) {
814 		ret = mcp23s08_irqchip_setup(mcp);
815 		if (ret)
816 			goto fail;
817 	}
818 
819 	if (one_regmap_config) {
820 		mcp->pinctrl_desc.name = devm_kasprintf(dev, GFP_KERNEL,
821 				"mcp23xxx-pinctrl.%d", raw_chip_address);
822 		if (!mcp->pinctrl_desc.name)
823 			return -ENOMEM;
824 	} else {
825 		mcp->pinctrl_desc.name = "mcp23xxx-pinctrl";
826 	}
827 	mcp->pinctrl_desc.pctlops = &mcp_pinctrl_ops;
828 	mcp->pinctrl_desc.confops = &mcp_pinconf_ops;
829 	mcp->pinctrl_desc.npins = mcp->chip.ngpio;
830 	if (mcp->pinctrl_desc.npins == 8)
831 		mcp->pinctrl_desc.pins = mcp23x08_pins;
832 	else if (mcp->pinctrl_desc.npins == 16)
833 		mcp->pinctrl_desc.pins = mcp23x17_pins;
834 	mcp->pinctrl_desc.owner = THIS_MODULE;
835 
836 	mcp->pctldev = devm_pinctrl_register(dev, &mcp->pinctrl_desc, mcp);
837 	if (IS_ERR(mcp->pctldev)) {
838 		ret = PTR_ERR(mcp->pctldev);
839 		goto fail;
840 	}
841 
842 	if (mcp->irq)
843 		ret = mcp23s08_irq_setup(mcp);
844 
845 fail:
846 	if (ret < 0)
847 		dev_dbg(dev, "can't setup chip %d, --> %d\n", addr, ret);
848 	return ret;
849 }
850 
851 /*----------------------------------------------------------------------*/
852 
853 #ifdef CONFIG_OF
854 #ifdef CONFIG_SPI_MASTER
855 static const struct of_device_id mcp23s08_spi_of_match[] = {
856 	{
857 		.compatible = "microchip,mcp23s08",
858 		.data = (void *) MCP_TYPE_S08,
859 	},
860 	{
861 		.compatible = "microchip,mcp23s17",
862 		.data = (void *) MCP_TYPE_S17,
863 	},
864 	{
865 		.compatible = "microchip,mcp23s18",
866 		.data = (void *) MCP_TYPE_S18,
867 	},
868 /* NOTE: The use of the mcp prefix is deprecated and will be removed. */
869 	{
870 		.compatible = "mcp,mcp23s08",
871 		.data = (void *) MCP_TYPE_S08,
872 	},
873 	{
874 		.compatible = "mcp,mcp23s17",
875 		.data = (void *) MCP_TYPE_S17,
876 	},
877 	{ },
878 };
879 MODULE_DEVICE_TABLE(of, mcp23s08_spi_of_match);
880 #endif
881 
882 #if IS_ENABLED(CONFIG_I2C)
883 static const struct of_device_id mcp23s08_i2c_of_match[] = {
884 	{
885 		.compatible = "microchip,mcp23008",
886 		.data = (void *) MCP_TYPE_008,
887 	},
888 	{
889 		.compatible = "microchip,mcp23017",
890 		.data = (void *) MCP_TYPE_017,
891 	},
892 	{
893 		.compatible = "microchip,mcp23018",
894 		.data = (void *) MCP_TYPE_018,
895 	},
896 /* NOTE: The use of the mcp prefix is deprecated and will be removed. */
897 	{
898 		.compatible = "mcp,mcp23008",
899 		.data = (void *) MCP_TYPE_008,
900 	},
901 	{
902 		.compatible = "mcp,mcp23017",
903 		.data = (void *) MCP_TYPE_017,
904 	},
905 	{ },
906 };
907 MODULE_DEVICE_TABLE(of, mcp23s08_i2c_of_match);
908 #endif
909 #endif /* CONFIG_OF */
910 
911 
912 #if IS_ENABLED(CONFIG_I2C)
913 
914 static int mcp230xx_probe(struct i2c_client *client,
915 				    const struct i2c_device_id *id)
916 {
917 	struct mcp23s08_platform_data *pdata, local_pdata;
918 	struct mcp23s08 *mcp;
919 	int status;
920 
921 	pdata = dev_get_platdata(&client->dev);
922 	if (!pdata) {
923 		pdata = &local_pdata;
924 		pdata->base = -1;
925 	}
926 
927 	mcp = devm_kzalloc(&client->dev, sizeof(*mcp), GFP_KERNEL);
928 	if (!mcp)
929 		return -ENOMEM;
930 
931 	mcp->irq = client->irq;
932 	mcp->irq_chip.name = dev_name(&client->dev);
933 	mcp->irq_chip.irq_mask = mcp23s08_irq_mask;
934 	mcp->irq_chip.irq_unmask = mcp23s08_irq_unmask;
935 	mcp->irq_chip.irq_set_type = mcp23s08_irq_set_type;
936 	mcp->irq_chip.irq_bus_lock = mcp23s08_irq_bus_lock;
937 	mcp->irq_chip.irq_bus_sync_unlock = mcp23s08_irq_bus_unlock;
938 
939 	status = mcp23s08_probe_one(mcp, &client->dev, client, client->addr,
940 				    id->driver_data, pdata->base, 0);
941 	if (status)
942 		return status;
943 
944 	i2c_set_clientdata(client, mcp);
945 
946 	return 0;
947 }
948 
949 static const struct i2c_device_id mcp230xx_id[] = {
950 	{ "mcp23008", MCP_TYPE_008 },
951 	{ "mcp23017", MCP_TYPE_017 },
952 	{ "mcp23018", MCP_TYPE_018 },
953 	{ },
954 };
955 MODULE_DEVICE_TABLE(i2c, mcp230xx_id);
956 
957 static struct i2c_driver mcp230xx_driver = {
958 	.driver = {
959 		.name	= "mcp230xx",
960 		.of_match_table = of_match_ptr(mcp23s08_i2c_of_match),
961 	},
962 	.probe		= mcp230xx_probe,
963 	.id_table	= mcp230xx_id,
964 };
965 
966 static int __init mcp23s08_i2c_init(void)
967 {
968 	return i2c_add_driver(&mcp230xx_driver);
969 }
970 
971 static void mcp23s08_i2c_exit(void)
972 {
973 	i2c_del_driver(&mcp230xx_driver);
974 }
975 
976 #else
977 
978 static int __init mcp23s08_i2c_init(void) { return 0; }
979 static void mcp23s08_i2c_exit(void) { }
980 
981 #endif /* CONFIG_I2C */
982 
983 /*----------------------------------------------------------------------*/
984 
985 #ifdef CONFIG_SPI_MASTER
986 
987 static int mcp23s08_probe(struct spi_device *spi)
988 {
989 	struct mcp23s08_platform_data	*pdata, local_pdata;
990 	unsigned			addr;
991 	int				chips = 0;
992 	struct mcp23s08_driver_data	*data;
993 	int				status, type;
994 	unsigned			ngpio = 0;
995 	const struct			of_device_id *match;
996 
997 	match = of_match_device(of_match_ptr(mcp23s08_spi_of_match), &spi->dev);
998 	if (match)
999 		type = (int)(uintptr_t)match->data;
1000 	else
1001 		type = spi_get_device_id(spi)->driver_data;
1002 
1003 	pdata = dev_get_platdata(&spi->dev);
1004 	if (!pdata) {
1005 		pdata = &local_pdata;
1006 		pdata->base = -1;
1007 
1008 		status = device_property_read_u32(&spi->dev,
1009 			"microchip,spi-present-mask", &pdata->spi_present_mask);
1010 		if (status) {
1011 			status = device_property_read_u32(&spi->dev,
1012 				"mcp,spi-present-mask",
1013 				&pdata->spi_present_mask);
1014 
1015 			if (status) {
1016 				dev_err(&spi->dev, "missing spi-present-mask");
1017 				return -ENODEV;
1018 			}
1019 		}
1020 	}
1021 
1022 	if (!pdata->spi_present_mask || pdata->spi_present_mask > 0xff) {
1023 		dev_err(&spi->dev, "invalid spi-present-mask");
1024 		return -ENODEV;
1025 	}
1026 
1027 	for (addr = 0; addr < MCP_MAX_DEV_PER_CS; addr++) {
1028 		if (pdata->spi_present_mask & BIT(addr))
1029 			chips++;
1030 	}
1031 
1032 	if (!chips)
1033 		return -ENODEV;
1034 
1035 	data = devm_kzalloc(&spi->dev,
1036 			    struct_size(data, chip, chips), GFP_KERNEL);
1037 	if (!data)
1038 		return -ENOMEM;
1039 
1040 	spi_set_drvdata(spi, data);
1041 
1042 	for (addr = 0; addr < MCP_MAX_DEV_PER_CS; addr++) {
1043 		if (!(pdata->spi_present_mask & BIT(addr)))
1044 			continue;
1045 		chips--;
1046 		data->mcp[addr] = &data->chip[chips];
1047 		data->mcp[addr]->irq = spi->irq;
1048 		data->mcp[addr]->irq_chip.name = dev_name(&spi->dev);
1049 		data->mcp[addr]->irq_chip.irq_mask = mcp23s08_irq_mask;
1050 		data->mcp[addr]->irq_chip.irq_unmask = mcp23s08_irq_unmask;
1051 		data->mcp[addr]->irq_chip.irq_set_type = mcp23s08_irq_set_type;
1052 		data->mcp[addr]->irq_chip.irq_bus_lock = mcp23s08_irq_bus_lock;
1053 		data->mcp[addr]->irq_chip.irq_bus_sync_unlock =
1054 			mcp23s08_irq_bus_unlock;
1055 		status = mcp23s08_probe_one(data->mcp[addr], &spi->dev, spi,
1056 					    0x40 | (addr << 1), type,
1057 					    pdata->base, addr);
1058 		if (status < 0)
1059 			return status;
1060 
1061 		if (pdata->base != -1)
1062 			pdata->base += data->mcp[addr]->chip.ngpio;
1063 		ngpio += data->mcp[addr]->chip.ngpio;
1064 	}
1065 	data->ngpio = ngpio;
1066 
1067 	return 0;
1068 }
1069 
1070 static const struct spi_device_id mcp23s08_ids[] = {
1071 	{ "mcp23s08", MCP_TYPE_S08 },
1072 	{ "mcp23s17", MCP_TYPE_S17 },
1073 	{ "mcp23s18", MCP_TYPE_S18 },
1074 	{ },
1075 };
1076 MODULE_DEVICE_TABLE(spi, mcp23s08_ids);
1077 
1078 static struct spi_driver mcp23s08_driver = {
1079 	.probe		= mcp23s08_probe,
1080 	.id_table	= mcp23s08_ids,
1081 	.driver = {
1082 		.name	= "mcp23s08",
1083 		.of_match_table = of_match_ptr(mcp23s08_spi_of_match),
1084 	},
1085 };
1086 
1087 static int __init mcp23s08_spi_init(void)
1088 {
1089 	return spi_register_driver(&mcp23s08_driver);
1090 }
1091 
1092 static void mcp23s08_spi_exit(void)
1093 {
1094 	spi_unregister_driver(&mcp23s08_driver);
1095 }
1096 
1097 #else
1098 
1099 static int __init mcp23s08_spi_init(void) { return 0; }
1100 static void mcp23s08_spi_exit(void) { }
1101 
1102 #endif /* CONFIG_SPI_MASTER */
1103 
1104 /*----------------------------------------------------------------------*/
1105 
1106 static int __init mcp23s08_init(void)
1107 {
1108 	int ret;
1109 
1110 	ret = mcp23s08_spi_init();
1111 	if (ret)
1112 		goto spi_fail;
1113 
1114 	ret = mcp23s08_i2c_init();
1115 	if (ret)
1116 		goto i2c_fail;
1117 
1118 	return 0;
1119 
1120  i2c_fail:
1121 	mcp23s08_spi_exit();
1122  spi_fail:
1123 	return ret;
1124 }
1125 /* register after spi/i2c postcore initcall and before
1126  * subsys initcalls that may rely on these GPIOs
1127  */
1128 subsys_initcall(mcp23s08_init);
1129 
1130 static void __exit mcp23s08_exit(void)
1131 {
1132 	mcp23s08_spi_exit();
1133 	mcp23s08_i2c_exit();
1134 }
1135 module_exit(mcp23s08_exit);
1136 
1137 MODULE_LICENSE("GPL");
1138