xref: /linux/drivers/pinctrl/pinctrl-mcp23s08.c (revision 18f90d372cf35b387663f1567de701e5393f6eb5)
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 		dev_err(mcp->dev, "Invalid config param %04x\n", param);
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_err(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 #ifdef CONFIG_DEBUG_FS
660 
661 #include <linux/seq_file.h>
662 
663 /*
664  * This compares the chip's registers with the register
665  * cache and corrects any incorrectly set register. This
666  * can be used to fix state for MCP23xxx, that temporary
667  * lost its power supply.
668  */
669 #define MCP23S08_CONFIG_REGS 7
670 static int __check_mcp23s08_reg_cache(struct mcp23s08 *mcp)
671 {
672 	int cached[MCP23S08_CONFIG_REGS];
673 	int err = 0, i;
674 
675 	/* read cached config registers */
676 	for (i = 0; i < MCP23S08_CONFIG_REGS; i++) {
677 		err = mcp_read(mcp, i, &cached[i]);
678 		if (err)
679 			goto out;
680 	}
681 
682 	regcache_cache_bypass(mcp->regmap, true);
683 
684 	for (i = 0; i < MCP23S08_CONFIG_REGS; i++) {
685 		int uncached;
686 		err = mcp_read(mcp, i, &uncached);
687 		if (err)
688 			goto out;
689 
690 		if (uncached != cached[i]) {
691 			dev_err(mcp->dev, "restoring reg 0x%02x from 0x%04x to 0x%04x (power-loss?)\n",
692 				i, uncached, cached[i]);
693 			mcp_write(mcp, i, cached[i]);
694 		}
695 	}
696 
697 out:
698 	if (err)
699 		dev_err(mcp->dev, "read error: reg=%02x, err=%d", i, err);
700 	regcache_cache_bypass(mcp->regmap, false);
701 	return err;
702 }
703 
704 /*
705  * This shows more info than the generic gpio dump code:
706  * pullups, deglitching, open drain drive.
707  */
708 static void mcp23s08_dbg_show(struct seq_file *s, struct gpio_chip *chip)
709 {
710 	struct mcp23s08	*mcp;
711 	char		bank;
712 	int		t;
713 	unsigned	mask;
714 	int iodir, gpio, gppu;
715 
716 	mcp = gpiochip_get_data(chip);
717 
718 	/* NOTE: we only handle one bank for now ... */
719 	bank = '0' + ((mcp->addr >> 1) & 0x7);
720 
721 	mutex_lock(&mcp->lock);
722 
723 	t = __check_mcp23s08_reg_cache(mcp);
724 	if (t) {
725 		seq_printf(s, " I/O Error\n");
726 		goto done;
727 	}
728 	t = mcp_read(mcp, MCP_IODIR, &iodir);
729 	if (t) {
730 		seq_printf(s, " I/O Error\n");
731 		goto done;
732 	}
733 	t = mcp_read(mcp, MCP_GPIO, &gpio);
734 	if (t) {
735 		seq_printf(s, " I/O Error\n");
736 		goto done;
737 	}
738 	t = mcp_read(mcp, MCP_GPPU, &gppu);
739 	if (t) {
740 		seq_printf(s, " I/O Error\n");
741 		goto done;
742 	}
743 
744 	for (t = 0, mask = BIT(0); t < chip->ngpio; t++, mask <<= 1) {
745 		const char *label;
746 
747 		label = gpiochip_is_requested(chip, t);
748 		if (!label)
749 			continue;
750 
751 		seq_printf(s, " gpio-%-3d P%c.%d (%-12s) %s %s %s\n",
752 			   chip->base + t, bank, t, label,
753 			   (iodir & mask) ? "in " : "out",
754 			   (gpio & mask) ? "hi" : "lo",
755 			   (gppu & mask) ? "up" : "  ");
756 		/* NOTE:  ignoring the irq-related registers */
757 	}
758 done:
759 	mutex_unlock(&mcp->lock);
760 }
761 
762 #else
763 #define mcp23s08_dbg_show	NULL
764 #endif
765 
766 /*----------------------------------------------------------------------*/
767 
768 static int mcp23s08_probe_one(struct mcp23s08 *mcp, struct device *dev,
769 			      void *data, unsigned addr, unsigned type,
770 			      unsigned int base, int cs)
771 {
772 	int status, ret;
773 	bool mirror = false;
774 	bool open_drain = false;
775 	struct regmap_config *one_regmap_config = NULL;
776 	int raw_chip_address = (addr & ~0x40) >> 1;
777 
778 	mutex_init(&mcp->lock);
779 
780 	mcp->dev = dev;
781 	mcp->addr = addr;
782 	mcp->irq_active_high = false;
783 
784 	mcp->chip.direction_input = mcp23s08_direction_input;
785 	mcp->chip.get = mcp23s08_get;
786 	mcp->chip.direction_output = mcp23s08_direction_output;
787 	mcp->chip.set = mcp23s08_set;
788 	mcp->chip.dbg_show = mcp23s08_dbg_show;
789 #ifdef CONFIG_OF_GPIO
790 	mcp->chip.of_gpio_n_cells = 2;
791 	mcp->chip.of_node = dev->of_node;
792 #endif
793 
794 	switch (type) {
795 #ifdef CONFIG_SPI_MASTER
796 	case MCP_TYPE_S08:
797 	case MCP_TYPE_S17:
798 		switch (type) {
799 		case MCP_TYPE_S08:
800 			one_regmap_config =
801 				devm_kmemdup(dev, &mcp23x08_regmap,
802 					sizeof(struct regmap_config), GFP_KERNEL);
803 			mcp->reg_shift = 0;
804 			mcp->chip.ngpio = 8;
805 			mcp->chip.label = devm_kasprintf(dev, GFP_KERNEL,
806 					"mcp23s08.%d", raw_chip_address);
807 			break;
808 		case MCP_TYPE_S17:
809 			one_regmap_config =
810 				devm_kmemdup(dev, &mcp23x17_regmap,
811 					sizeof(struct regmap_config), GFP_KERNEL);
812 			mcp->reg_shift = 1;
813 			mcp->chip.ngpio = 16;
814 			mcp->chip.label = devm_kasprintf(dev, GFP_KERNEL,
815 					"mcp23s17.%d", raw_chip_address);
816 			break;
817 		}
818 		if (!one_regmap_config)
819 			return -ENOMEM;
820 
821 		one_regmap_config->name = devm_kasprintf(dev, GFP_KERNEL, "%d", raw_chip_address);
822 		mcp->regmap = devm_regmap_init(dev, &mcp23sxx_spi_regmap, mcp,
823 					       one_regmap_config);
824 		break;
825 
826 	case MCP_TYPE_S18:
827 		one_regmap_config =
828 			devm_kmemdup(dev, &mcp23x17_regmap,
829 				sizeof(struct regmap_config), GFP_KERNEL);
830 		if (!one_regmap_config)
831 			return -ENOMEM;
832 		mcp->regmap = devm_regmap_init(dev, &mcp23sxx_spi_regmap, mcp,
833 					       one_regmap_config);
834 		mcp->reg_shift = 1;
835 		mcp->chip.ngpio = 16;
836 		mcp->chip.label = "mcp23s18";
837 		break;
838 #endif /* CONFIG_SPI_MASTER */
839 
840 #if IS_ENABLED(CONFIG_I2C)
841 	case MCP_TYPE_008:
842 		mcp->regmap = devm_regmap_init_i2c(data, &mcp23x08_regmap);
843 		mcp->reg_shift = 0;
844 		mcp->chip.ngpio = 8;
845 		mcp->chip.label = "mcp23008";
846 		break;
847 
848 	case MCP_TYPE_017:
849 		mcp->regmap = devm_regmap_init_i2c(data, &mcp23x17_regmap);
850 		mcp->reg_shift = 1;
851 		mcp->chip.ngpio = 16;
852 		mcp->chip.label = "mcp23017";
853 		break;
854 
855 	case MCP_TYPE_018:
856 		mcp->regmap = devm_regmap_init_i2c(data, &mcp23x17_regmap);
857 		mcp->reg_shift = 1;
858 		mcp->chip.ngpio = 16;
859 		mcp->chip.label = "mcp23018";
860 		break;
861 #endif /* CONFIG_I2C */
862 
863 	default:
864 		dev_err(dev, "invalid device type (%d)\n", type);
865 		return -EINVAL;
866 	}
867 
868 	if (IS_ERR(mcp->regmap))
869 		return PTR_ERR(mcp->regmap);
870 
871 	mcp->chip.base = base;
872 	mcp->chip.can_sleep = true;
873 	mcp->chip.parent = dev;
874 	mcp->chip.owner = THIS_MODULE;
875 
876 	/* verify MCP_IOCON.SEQOP = 0, so sequential reads work,
877 	 * and MCP_IOCON.HAEN = 1, so we work with all chips.
878 	 */
879 
880 	ret = mcp_read(mcp, MCP_IOCON, &status);
881 	if (ret < 0)
882 		goto fail;
883 
884 	mcp->irq_controller =
885 		device_property_read_bool(dev, "interrupt-controller");
886 	if (mcp->irq && mcp->irq_controller) {
887 		mcp->irq_active_high =
888 			device_property_read_bool(dev,
889 					      "microchip,irq-active-high");
890 
891 		mirror = device_property_read_bool(dev, "microchip,irq-mirror");
892 		open_drain = device_property_read_bool(dev, "drive-open-drain");
893 	}
894 
895 	if ((status & IOCON_SEQOP) || !(status & IOCON_HAEN) || mirror ||
896 	     mcp->irq_active_high || open_drain) {
897 		/* mcp23s17 has IOCON twice, make sure they are in sync */
898 		status &= ~(IOCON_SEQOP | (IOCON_SEQOP << 8));
899 		status |= IOCON_HAEN | (IOCON_HAEN << 8);
900 		if (mcp->irq_active_high)
901 			status |= IOCON_INTPOL | (IOCON_INTPOL << 8);
902 		else
903 			status &= ~(IOCON_INTPOL | (IOCON_INTPOL << 8));
904 
905 		if (mirror)
906 			status |= IOCON_MIRROR | (IOCON_MIRROR << 8);
907 
908 		if (open_drain)
909 			status |= IOCON_ODR | (IOCON_ODR << 8);
910 
911 		if (type == MCP_TYPE_S18 || type == MCP_TYPE_018)
912 			status |= IOCON_INTCC | (IOCON_INTCC << 8);
913 
914 		ret = mcp_write(mcp, MCP_IOCON, status);
915 		if (ret < 0)
916 			goto fail;
917 	}
918 
919 	if (mcp->irq && mcp->irq_controller) {
920 		ret = mcp23s08_irqchip_setup(mcp);
921 		if (ret)
922 			goto fail;
923 	}
924 
925 	ret = devm_gpiochip_add_data(dev, &mcp->chip, mcp);
926 	if (ret < 0)
927 		goto fail;
928 
929 	if (one_regmap_config) {
930 		mcp->pinctrl_desc.name = devm_kasprintf(dev, GFP_KERNEL,
931 				"mcp23xxx-pinctrl.%d", raw_chip_address);
932 		if (!mcp->pinctrl_desc.name)
933 			return -ENOMEM;
934 	} else {
935 		mcp->pinctrl_desc.name = "mcp23xxx-pinctrl";
936 	}
937 	mcp->pinctrl_desc.pctlops = &mcp_pinctrl_ops;
938 	mcp->pinctrl_desc.confops = &mcp_pinconf_ops;
939 	mcp->pinctrl_desc.npins = mcp->chip.ngpio;
940 	if (mcp->pinctrl_desc.npins == 8)
941 		mcp->pinctrl_desc.pins = mcp23x08_pins;
942 	else if (mcp->pinctrl_desc.npins == 16)
943 		mcp->pinctrl_desc.pins = mcp23x17_pins;
944 	mcp->pinctrl_desc.owner = THIS_MODULE;
945 
946 	mcp->pctldev = devm_pinctrl_register(dev, &mcp->pinctrl_desc, mcp);
947 	if (IS_ERR(mcp->pctldev)) {
948 		ret = PTR_ERR(mcp->pctldev);
949 		goto fail;
950 	}
951 
952 	if (mcp->irq)
953 		ret = mcp23s08_irq_setup(mcp);
954 
955 fail:
956 	if (ret < 0)
957 		dev_dbg(dev, "can't setup chip %d, --> %d\n", addr, ret);
958 	return ret;
959 }
960 
961 /*----------------------------------------------------------------------*/
962 
963 #ifdef CONFIG_OF
964 #ifdef CONFIG_SPI_MASTER
965 static const struct of_device_id mcp23s08_spi_of_match[] = {
966 	{
967 		.compatible = "microchip,mcp23s08",
968 		.data = (void *) MCP_TYPE_S08,
969 	},
970 	{
971 		.compatible = "microchip,mcp23s17",
972 		.data = (void *) MCP_TYPE_S17,
973 	},
974 	{
975 		.compatible = "microchip,mcp23s18",
976 		.data = (void *) MCP_TYPE_S18,
977 	},
978 /* NOTE: The use of the mcp prefix is deprecated and will be removed. */
979 	{
980 		.compatible = "mcp,mcp23s08",
981 		.data = (void *) MCP_TYPE_S08,
982 	},
983 	{
984 		.compatible = "mcp,mcp23s17",
985 		.data = (void *) MCP_TYPE_S17,
986 	},
987 	{ },
988 };
989 MODULE_DEVICE_TABLE(of, mcp23s08_spi_of_match);
990 #endif
991 
992 #if IS_ENABLED(CONFIG_I2C)
993 static const struct of_device_id mcp23s08_i2c_of_match[] = {
994 	{
995 		.compatible = "microchip,mcp23008",
996 		.data = (void *) MCP_TYPE_008,
997 	},
998 	{
999 		.compatible = "microchip,mcp23017",
1000 		.data = (void *) MCP_TYPE_017,
1001 	},
1002 	{
1003 		.compatible = "microchip,mcp23018",
1004 		.data = (void *) MCP_TYPE_018,
1005 	},
1006 /* NOTE: The use of the mcp prefix is deprecated and will be removed. */
1007 	{
1008 		.compatible = "mcp,mcp23008",
1009 		.data = (void *) MCP_TYPE_008,
1010 	},
1011 	{
1012 		.compatible = "mcp,mcp23017",
1013 		.data = (void *) MCP_TYPE_017,
1014 	},
1015 	{ },
1016 };
1017 MODULE_DEVICE_TABLE(of, mcp23s08_i2c_of_match);
1018 #endif
1019 #endif /* CONFIG_OF */
1020 
1021 
1022 #if IS_ENABLED(CONFIG_I2C)
1023 
1024 static int mcp230xx_probe(struct i2c_client *client,
1025 				    const struct i2c_device_id *id)
1026 {
1027 	struct mcp23s08_platform_data *pdata, local_pdata;
1028 	struct mcp23s08 *mcp;
1029 	int status;
1030 
1031 	pdata = dev_get_platdata(&client->dev);
1032 	if (!pdata) {
1033 		pdata = &local_pdata;
1034 		pdata->base = -1;
1035 	}
1036 
1037 	mcp = devm_kzalloc(&client->dev, sizeof(*mcp), GFP_KERNEL);
1038 	if (!mcp)
1039 		return -ENOMEM;
1040 
1041 	mcp->irq = client->irq;
1042 	mcp->irq_chip.name = dev_name(&client->dev);
1043 	mcp->irq_chip.irq_mask = mcp23s08_irq_mask;
1044 	mcp->irq_chip.irq_unmask = mcp23s08_irq_unmask;
1045 	mcp->irq_chip.irq_set_type = mcp23s08_irq_set_type;
1046 	mcp->irq_chip.irq_bus_lock = mcp23s08_irq_bus_lock;
1047 	mcp->irq_chip.irq_bus_sync_unlock = mcp23s08_irq_bus_unlock;
1048 
1049 	status = mcp23s08_probe_one(mcp, &client->dev, client, client->addr,
1050 				    id->driver_data, pdata->base, 0);
1051 	if (status)
1052 		return status;
1053 
1054 	i2c_set_clientdata(client, mcp);
1055 
1056 	return 0;
1057 }
1058 
1059 static const struct i2c_device_id mcp230xx_id[] = {
1060 	{ "mcp23008", MCP_TYPE_008 },
1061 	{ "mcp23017", MCP_TYPE_017 },
1062 	{ "mcp23018", MCP_TYPE_018 },
1063 	{ },
1064 };
1065 MODULE_DEVICE_TABLE(i2c, mcp230xx_id);
1066 
1067 static struct i2c_driver mcp230xx_driver = {
1068 	.driver = {
1069 		.name	= "mcp230xx",
1070 		.of_match_table = of_match_ptr(mcp23s08_i2c_of_match),
1071 	},
1072 	.probe		= mcp230xx_probe,
1073 	.id_table	= mcp230xx_id,
1074 };
1075 
1076 static int __init mcp23s08_i2c_init(void)
1077 {
1078 	return i2c_add_driver(&mcp230xx_driver);
1079 }
1080 
1081 static void mcp23s08_i2c_exit(void)
1082 {
1083 	i2c_del_driver(&mcp230xx_driver);
1084 }
1085 
1086 #else
1087 
1088 static int __init mcp23s08_i2c_init(void) { return 0; }
1089 static void mcp23s08_i2c_exit(void) { }
1090 
1091 #endif /* CONFIG_I2C */
1092 
1093 /*----------------------------------------------------------------------*/
1094 
1095 #ifdef CONFIG_SPI_MASTER
1096 
1097 static int mcp23s08_probe(struct spi_device *spi)
1098 {
1099 	struct mcp23s08_platform_data	*pdata, local_pdata;
1100 	unsigned			addr;
1101 	int				chips = 0;
1102 	struct mcp23s08_driver_data	*data;
1103 	int				status, type;
1104 	unsigned			ngpio = 0;
1105 	const struct			of_device_id *match;
1106 
1107 	match = of_match_device(of_match_ptr(mcp23s08_spi_of_match), &spi->dev);
1108 	if (match)
1109 		type = (int)(uintptr_t)match->data;
1110 	else
1111 		type = spi_get_device_id(spi)->driver_data;
1112 
1113 	pdata = dev_get_platdata(&spi->dev);
1114 	if (!pdata) {
1115 		pdata = &local_pdata;
1116 		pdata->base = -1;
1117 
1118 		status = device_property_read_u32(&spi->dev,
1119 			"microchip,spi-present-mask", &pdata->spi_present_mask);
1120 		if (status) {
1121 			status = device_property_read_u32(&spi->dev,
1122 				"mcp,spi-present-mask",
1123 				&pdata->spi_present_mask);
1124 
1125 			if (status) {
1126 				dev_err(&spi->dev, "missing spi-present-mask");
1127 				return -ENODEV;
1128 			}
1129 		}
1130 	}
1131 
1132 	if (!pdata->spi_present_mask || pdata->spi_present_mask > 0xff) {
1133 		dev_err(&spi->dev, "invalid spi-present-mask");
1134 		return -ENODEV;
1135 	}
1136 
1137 	for (addr = 0; addr < MCP_MAX_DEV_PER_CS; addr++) {
1138 		if (pdata->spi_present_mask & BIT(addr))
1139 			chips++;
1140 	}
1141 
1142 	if (!chips)
1143 		return -ENODEV;
1144 
1145 	data = devm_kzalloc(&spi->dev,
1146 			    struct_size(data, chip, chips), GFP_KERNEL);
1147 	if (!data)
1148 		return -ENOMEM;
1149 
1150 	spi_set_drvdata(spi, data);
1151 
1152 	for (addr = 0; addr < MCP_MAX_DEV_PER_CS; addr++) {
1153 		if (!(pdata->spi_present_mask & BIT(addr)))
1154 			continue;
1155 		chips--;
1156 		data->mcp[addr] = &data->chip[chips];
1157 		data->mcp[addr]->irq = spi->irq;
1158 		data->mcp[addr]->irq_chip.name = dev_name(&spi->dev);
1159 		data->mcp[addr]->irq_chip.irq_mask = mcp23s08_irq_mask;
1160 		data->mcp[addr]->irq_chip.irq_unmask = mcp23s08_irq_unmask;
1161 		data->mcp[addr]->irq_chip.irq_set_type = mcp23s08_irq_set_type;
1162 		data->mcp[addr]->irq_chip.irq_bus_lock = mcp23s08_irq_bus_lock;
1163 		data->mcp[addr]->irq_chip.irq_bus_sync_unlock =
1164 			mcp23s08_irq_bus_unlock;
1165 		status = mcp23s08_probe_one(data->mcp[addr], &spi->dev, spi,
1166 					    0x40 | (addr << 1), type,
1167 					    pdata->base, addr);
1168 		if (status < 0)
1169 			return status;
1170 
1171 		if (pdata->base != -1)
1172 			pdata->base += data->mcp[addr]->chip.ngpio;
1173 		ngpio += data->mcp[addr]->chip.ngpio;
1174 	}
1175 	data->ngpio = ngpio;
1176 
1177 	return 0;
1178 }
1179 
1180 static const struct spi_device_id mcp23s08_ids[] = {
1181 	{ "mcp23s08", MCP_TYPE_S08 },
1182 	{ "mcp23s17", MCP_TYPE_S17 },
1183 	{ "mcp23s18", MCP_TYPE_S18 },
1184 	{ },
1185 };
1186 MODULE_DEVICE_TABLE(spi, mcp23s08_ids);
1187 
1188 static struct spi_driver mcp23s08_driver = {
1189 	.probe		= mcp23s08_probe,
1190 	.id_table	= mcp23s08_ids,
1191 	.driver = {
1192 		.name	= "mcp23s08",
1193 		.of_match_table = of_match_ptr(mcp23s08_spi_of_match),
1194 	},
1195 };
1196 
1197 static int __init mcp23s08_spi_init(void)
1198 {
1199 	return spi_register_driver(&mcp23s08_driver);
1200 }
1201 
1202 static void mcp23s08_spi_exit(void)
1203 {
1204 	spi_unregister_driver(&mcp23s08_driver);
1205 }
1206 
1207 #else
1208 
1209 static int __init mcp23s08_spi_init(void) { return 0; }
1210 static void mcp23s08_spi_exit(void) { }
1211 
1212 #endif /* CONFIG_SPI_MASTER */
1213 
1214 /*----------------------------------------------------------------------*/
1215 
1216 static int __init mcp23s08_init(void)
1217 {
1218 	int ret;
1219 
1220 	ret = mcp23s08_spi_init();
1221 	if (ret)
1222 		goto spi_fail;
1223 
1224 	ret = mcp23s08_i2c_init();
1225 	if (ret)
1226 		goto i2c_fail;
1227 
1228 	return 0;
1229 
1230  i2c_fail:
1231 	mcp23s08_spi_exit();
1232  spi_fail:
1233 	return ret;
1234 }
1235 /* register after spi/i2c postcore initcall and before
1236  * subsys initcalls that may rely on these GPIOs
1237  */
1238 subsys_initcall(mcp23s08_init);
1239 
1240 static void __exit mcp23s08_exit(void)
1241 {
1242 	mcp23s08_spi_exit();
1243 	mcp23s08_i2c_exit();
1244 }
1245 module_exit(mcp23s08_exit);
1246 
1247 MODULE_LICENSE("GPL");
1248