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