xref: /linux/drivers/pinctrl/pinctrl-mcp23s08.c (revision a110f942672c8995dc1cacb5a44c6730856743aa)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /* MCP23S08 SPI/I2C GPIO driver */
3 
4 #include <linux/bitops.h>
5 #include <linux/kernel.h>
6 #include <linux/device.h>
7 #include <linux/mutex.h>
8 #include <linux/mod_devicetable.h>
9 #include <linux/module.h>
10 #include <linux/export.h>
11 #include <linux/gpio/driver.h>
12 #include <linux/gpio/consumer.h>
13 #include <linux/seq_file.h>
14 #include <linux/slab.h>
15 #include <asm/byteorder.h>
16 #include <linux/interrupt.h>
17 #include <linux/regmap.h>
18 #include <linux/pinctrl/pinctrl.h>
19 #include <linux/pinctrl/pinconf.h>
20 #include <linux/pinctrl/pinconf-generic.h>
21 
22 #include "pinctrl-mcp23s08.h"
23 
24 /* Registers are all 8 bits wide.
25  *
26  * The mcp23s17 has twice as many bits, and can be configured to work
27  * with either 16 bit registers or with two adjacent 8 bit banks.
28  */
29 #define MCP_IODIR	0x00		/* init/reset:  all ones */
30 #define MCP_IPOL	0x01
31 #define MCP_GPINTEN	0x02
32 #define MCP_DEFVAL	0x03
33 #define MCP_INTCON	0x04
34 #define MCP_IOCON	0x05
35 #	define IOCON_MIRROR	(1 << 6)
36 #	define IOCON_SEQOP	(1 << 5)
37 #	define IOCON_HAEN	(1 << 3)
38 #	define IOCON_ODR	(1 << 2)
39 #	define IOCON_INTPOL	(1 << 1)
40 #	define IOCON_INTCC	(1)
41 #define MCP_GPPU	0x06
42 #define MCP_INTF	0x07
43 #define MCP_INTCAP	0x08
44 #define MCP_GPIO	0x09
45 #define MCP_OLAT	0x0a
46 
47 static const struct regmap_range mcp23x08_volatile_range = {
48 	.range_min = MCP_INTF,
49 	.range_max = MCP_GPIO,
50 };
51 
52 static const struct regmap_access_table mcp23x08_volatile_table = {
53 	.yes_ranges = &mcp23x08_volatile_range,
54 	.n_yes_ranges = 1,
55 };
56 
57 static const struct regmap_range mcp23x08_precious_range = {
58 	.range_min = MCP_GPIO,
59 	.range_max = MCP_GPIO,
60 };
61 
62 static const struct regmap_access_table mcp23x08_precious_table = {
63 	.yes_ranges = &mcp23x08_precious_range,
64 	.n_yes_ranges = 1,
65 };
66 
67 const struct regmap_config mcp23x08_regmap = {
68 	.reg_bits = 8,
69 	.val_bits = 8,
70 
71 	.reg_stride = 1,
72 	.volatile_table = &mcp23x08_volatile_table,
73 	.precious_table = &mcp23x08_precious_table,
74 	.num_reg_defaults_raw = MCP_OLAT + 1,
75 	.cache_type = REGCACHE_MAPLE,
76 	.max_register = MCP_OLAT,
77 	.disable_locking = true, /* mcp->lock protects the regmap */
78 };
79 EXPORT_SYMBOL_GPL(mcp23x08_regmap);
80 
81 static const struct regmap_range mcp23x17_volatile_range = {
82 	.range_min = MCP_INTF << 1,
83 	.range_max = MCP_GPIO << 1,
84 };
85 
86 static const struct regmap_access_table mcp23x17_volatile_table = {
87 	.yes_ranges = &mcp23x17_volatile_range,
88 	.n_yes_ranges = 1,
89 };
90 
91 static const struct regmap_range mcp23x17_precious_range = {
92 	.range_min = MCP_INTCAP << 1,
93 	.range_max = MCP_GPIO << 1,
94 };
95 
96 static const struct regmap_access_table mcp23x17_precious_table = {
97 	.yes_ranges = &mcp23x17_precious_range,
98 	.n_yes_ranges = 1,
99 };
100 
101 const struct regmap_config mcp23x17_regmap = {
102 	.reg_bits = 8,
103 	.val_bits = 16,
104 
105 	.reg_stride = 2,
106 	.max_register = MCP_OLAT << 1,
107 	.volatile_table = &mcp23x17_volatile_table,
108 	.precious_table = &mcp23x17_precious_table,
109 	.num_reg_defaults_raw = MCP_OLAT + 1,
110 	.cache_type = REGCACHE_MAPLE,
111 	.val_format_endian = REGMAP_ENDIAN_LITTLE,
112 	.disable_locking = true, /* mcp->lock protects the regmap */
113 };
114 EXPORT_SYMBOL_GPL(mcp23x17_regmap);
115 
mcp_read(struct mcp23s08 * mcp,unsigned int reg,unsigned int * val)116 static int mcp_read(struct mcp23s08 *mcp, unsigned int reg, unsigned int *val)
117 {
118 	return regmap_read(mcp->regmap, reg << mcp->reg_shift, val);
119 }
120 
mcp_write(struct mcp23s08 * mcp,unsigned int reg,unsigned int val)121 static int mcp_write(struct mcp23s08 *mcp, unsigned int reg, unsigned int val)
122 {
123 	return regmap_write(mcp->regmap, reg << mcp->reg_shift, val);
124 }
125 
mcp_update_bits(struct mcp23s08 * mcp,unsigned int reg,unsigned int mask,unsigned int val)126 static int mcp_update_bits(struct mcp23s08 *mcp, unsigned int reg,
127 			   unsigned int mask, unsigned int val)
128 {
129 	return regmap_update_bits(mcp->regmap, reg << mcp->reg_shift,
130 				  mask, val);
131 }
132 
mcp_set_bit(struct mcp23s08 * mcp,unsigned int reg,unsigned int pin,bool enabled)133 static int mcp_set_bit(struct mcp23s08 *mcp, unsigned int reg,
134 		       unsigned int pin, bool enabled)
135 {
136 	u16 mask = BIT(pin);
137 	return mcp_update_bits(mcp, reg, mask, enabled ? mask : 0);
138 }
139 
140 static const struct pinctrl_pin_desc mcp23x08_pins[] = {
141 	PINCTRL_PIN(0, "gpio0"),
142 	PINCTRL_PIN(1, "gpio1"),
143 	PINCTRL_PIN(2, "gpio2"),
144 	PINCTRL_PIN(3, "gpio3"),
145 	PINCTRL_PIN(4, "gpio4"),
146 	PINCTRL_PIN(5, "gpio5"),
147 	PINCTRL_PIN(6, "gpio6"),
148 	PINCTRL_PIN(7, "gpio7"),
149 };
150 
151 static const struct pinctrl_pin_desc mcp23x17_pins[] = {
152 	PINCTRL_PIN(0, "gpio0"),
153 	PINCTRL_PIN(1, "gpio1"),
154 	PINCTRL_PIN(2, "gpio2"),
155 	PINCTRL_PIN(3, "gpio3"),
156 	PINCTRL_PIN(4, "gpio4"),
157 	PINCTRL_PIN(5, "gpio5"),
158 	PINCTRL_PIN(6, "gpio6"),
159 	PINCTRL_PIN(7, "gpio7"),
160 	PINCTRL_PIN(8, "gpio8"),
161 	PINCTRL_PIN(9, "gpio9"),
162 	PINCTRL_PIN(10, "gpio10"),
163 	PINCTRL_PIN(11, "gpio11"),
164 	PINCTRL_PIN(12, "gpio12"),
165 	PINCTRL_PIN(13, "gpio13"),
166 	PINCTRL_PIN(14, "gpio14"),
167 	PINCTRL_PIN(15, "gpio15"),
168 };
169 
mcp_pinctrl_get_groups_count(struct pinctrl_dev * pctldev)170 static int mcp_pinctrl_get_groups_count(struct pinctrl_dev *pctldev)
171 {
172 	return 0;
173 }
174 
mcp_pinctrl_get_group_name(struct pinctrl_dev * pctldev,unsigned int group)175 static const char *mcp_pinctrl_get_group_name(struct pinctrl_dev *pctldev,
176 						unsigned int group)
177 {
178 	return NULL;
179 }
180 
mcp_pinctrl_get_group_pins(struct pinctrl_dev * pctldev,unsigned int group,const unsigned int ** pins,unsigned int * num_pins)181 static int mcp_pinctrl_get_group_pins(struct pinctrl_dev *pctldev,
182 					unsigned int group,
183 					const unsigned int **pins,
184 					unsigned int *num_pins)
185 {
186 	return -ENOTSUPP;
187 }
188 
189 static const struct pinctrl_ops mcp_pinctrl_ops = {
190 	.get_groups_count = mcp_pinctrl_get_groups_count,
191 	.get_group_name = mcp_pinctrl_get_group_name,
192 	.get_group_pins = mcp_pinctrl_get_group_pins,
193 #ifdef CONFIG_OF
194 	.dt_node_to_map = pinconf_generic_dt_node_to_map_pin,
195 	.dt_free_map = pinconf_generic_dt_free_map,
196 #endif
197 };
198 
mcp_pinconf_get(struct pinctrl_dev * pctldev,unsigned int pin,unsigned long * config)199 static int mcp_pinconf_get(struct pinctrl_dev *pctldev, unsigned int pin,
200 			      unsigned long *config)
201 {
202 	struct mcp23s08 *mcp = pinctrl_dev_get_drvdata(pctldev);
203 	enum pin_config_param param = pinconf_to_config_param(*config);
204 	unsigned int data, status;
205 	int ret;
206 
207 	switch (param) {
208 	case PIN_CONFIG_BIAS_PULL_UP:
209 		mutex_lock(&mcp->lock);
210 		ret = mcp_read(mcp, MCP_GPPU, &data);
211 		mutex_unlock(&mcp->lock);
212 		if (ret < 0)
213 			return ret;
214 		status = (data & BIT(pin)) ? 1 : 0;
215 		break;
216 	default:
217 		return -ENOTSUPP;
218 	}
219 
220 	*config = 0;
221 
222 	return status ? 0 : -EINVAL;
223 }
224 
mcp_pinconf_set(struct pinctrl_dev * pctldev,unsigned int pin,unsigned long * configs,unsigned int num_configs)225 static int mcp_pinconf_set(struct pinctrl_dev *pctldev, unsigned int pin,
226 			      unsigned long *configs, unsigned int num_configs)
227 {
228 	struct mcp23s08 *mcp = pinctrl_dev_get_drvdata(pctldev);
229 	enum pin_config_param param;
230 	u32 arg;
231 	int ret = 0;
232 	int i;
233 
234 	for (i = 0; i < num_configs; i++) {
235 		param = pinconf_to_config_param(configs[i]);
236 		arg = pinconf_to_config_argument(configs[i]);
237 
238 		switch (param) {
239 		case PIN_CONFIG_BIAS_PULL_UP:
240 			mutex_lock(&mcp->lock);
241 			ret = mcp_set_bit(mcp, MCP_GPPU, pin, arg);
242 			mutex_unlock(&mcp->lock);
243 			break;
244 		default:
245 			dev_dbg(mcp->dev, "Invalid config param %04x\n", param);
246 			return -ENOTSUPP;
247 		}
248 	}
249 
250 	return ret;
251 }
252 
253 static const struct pinconf_ops mcp_pinconf_ops = {
254 	.pin_config_get = mcp_pinconf_get,
255 	.pin_config_set = mcp_pinconf_set,
256 	.is_generic = true,
257 };
258 
259 /*----------------------------------------------------------------------*/
260 
mcp23s08_direction_input(struct gpio_chip * chip,unsigned offset)261 static int mcp23s08_direction_input(struct gpio_chip *chip, unsigned offset)
262 {
263 	struct mcp23s08	*mcp = gpiochip_get_data(chip);
264 	int status;
265 
266 	mutex_lock(&mcp->lock);
267 	status = mcp_set_bit(mcp, MCP_IODIR, offset, true);
268 	mutex_unlock(&mcp->lock);
269 
270 	return status;
271 }
272 
mcp23s08_get(struct gpio_chip * chip,unsigned offset)273 static int mcp23s08_get(struct gpio_chip *chip, unsigned offset)
274 {
275 	struct mcp23s08	*mcp = gpiochip_get_data(chip);
276 	int status, ret;
277 
278 	mutex_lock(&mcp->lock);
279 
280 	/* REVISIT reading this clears any IRQ ... */
281 	ret = mcp_read(mcp, MCP_GPIO, &status);
282 	if (ret < 0)
283 		status = 0;
284 	else {
285 		mcp->cached_gpio = status;
286 		status = !!(status & (1 << offset));
287 	}
288 
289 	mutex_unlock(&mcp->lock);
290 	return status;
291 }
292 
mcp23s08_get_multiple(struct gpio_chip * chip,unsigned long * mask,unsigned long * bits)293 static int mcp23s08_get_multiple(struct gpio_chip *chip,
294 				 unsigned long *mask, unsigned long *bits)
295 {
296 	struct mcp23s08 *mcp = gpiochip_get_data(chip);
297 	unsigned int status;
298 	int ret;
299 
300 	mutex_lock(&mcp->lock);
301 
302 	/* REVISIT reading this clears any IRQ ... */
303 	ret = mcp_read(mcp, MCP_GPIO, &status);
304 	if (ret < 0)
305 		status = 0;
306 	else {
307 		mcp->cached_gpio = status;
308 		*bits = status;
309 	}
310 
311 	mutex_unlock(&mcp->lock);
312 	return ret;
313 }
314 
__mcp23s08_set(struct mcp23s08 * mcp,unsigned mask,bool value)315 static int __mcp23s08_set(struct mcp23s08 *mcp, unsigned mask, bool value)
316 {
317 	return mcp_update_bits(mcp, MCP_OLAT, mask, value ? mask : 0);
318 }
319 
mcp23s08_set(struct gpio_chip * chip,unsigned int offset,int value)320 static int mcp23s08_set(struct gpio_chip *chip, unsigned int offset, int value)
321 {
322 	struct mcp23s08	*mcp = gpiochip_get_data(chip);
323 	unsigned mask = BIT(offset);
324 	int ret;
325 
326 	mutex_lock(&mcp->lock);
327 	ret = __mcp23s08_set(mcp, mask, !!value);
328 	mutex_unlock(&mcp->lock);
329 
330 	return ret;
331 }
332 
mcp23s08_set_multiple(struct gpio_chip * chip,unsigned long * mask,unsigned long * bits)333 static int mcp23s08_set_multiple(struct gpio_chip *chip,
334 				 unsigned long *mask, unsigned long *bits)
335 {
336 	struct mcp23s08	*mcp = gpiochip_get_data(chip);
337 	int ret;
338 
339 	mutex_lock(&mcp->lock);
340 	ret = mcp_update_bits(mcp, MCP_OLAT, *mask, *bits);
341 	mutex_unlock(&mcp->lock);
342 
343 	return ret;
344 }
345 
346 static int
mcp23s08_direction_output(struct gpio_chip * chip,unsigned offset,int value)347 mcp23s08_direction_output(struct gpio_chip *chip, unsigned offset, int value)
348 {
349 	struct mcp23s08	*mcp = gpiochip_get_data(chip);
350 	unsigned mask = BIT(offset);
351 	int status;
352 
353 	mutex_lock(&mcp->lock);
354 	status = __mcp23s08_set(mcp, mask, value);
355 	if (status == 0) {
356 		status = mcp_update_bits(mcp, MCP_IODIR, mask, 0);
357 	}
358 	mutex_unlock(&mcp->lock);
359 	return status;
360 }
361 
362 /*----------------------------------------------------------------------*/
mcp23s08_irq(int irq,void * data)363 static irqreturn_t mcp23s08_irq(int irq, void *data)
364 {
365 	struct mcp23s08 *mcp = data;
366 	int intcap, intcon, intf, i, gpio, gpio_orig, intcap_mask, defval, gpinten;
367 	bool need_unmask = false;
368 	unsigned long int enabled_interrupts;
369 	unsigned int child_irq;
370 	bool intf_set, intcap_changed, gpio_bit_changed,
371 		defval_changed, gpio_set;
372 
373 	mutex_lock(&mcp->lock);
374 	if (mcp_read(mcp, MCP_INTF, &intf))
375 		goto unlock;
376 
377 	if (intf == 0) {
378 		/* There is no interrupt pending */
379 		goto unlock;
380 	}
381 
382 	if (mcp_read(mcp, MCP_INTCON, &intcon))
383 		goto unlock;
384 
385 	if (mcp_read(mcp, MCP_GPINTEN, &gpinten))
386 		goto unlock;
387 
388 	if (mcp_read(mcp, MCP_DEFVAL, &defval))
389 		goto unlock;
390 
391 	/* Mask level interrupts to avoid their immediate reactivation after clearing */
392 	if (intcon) {
393 		need_unmask = true;
394 		if (mcp_write(mcp, MCP_GPINTEN, gpinten & ~intcon))
395 			goto unlock;
396 	}
397 
398 	if (mcp_read(mcp, MCP_INTCAP, &intcap))
399 		goto unlock;
400 
401 	/* This clears the interrupt(configurable on S18) */
402 	if (mcp_read(mcp, MCP_GPIO, &gpio))
403 		goto unlock;
404 
405 	gpio_orig = mcp->cached_gpio;
406 	mcp->cached_gpio = gpio;
407 	mutex_unlock(&mcp->lock);
408 
409 	dev_dbg(mcp->chip.parent,
410 		"intcap 0x%04X intf 0x%04X gpio_orig 0x%04X gpio 0x%04X\n",
411 		intcap, intf, gpio_orig, gpio);
412 
413 	enabled_interrupts = gpinten;
414 	for_each_set_bit(i, &enabled_interrupts, mcp->chip.ngpio) {
415 		/*
416 		 * We must check all of the inputs with enabled interrupts
417 		 * on the chip, otherwise we may not notice a change
418 		 * on more than one pin.
419 		 *
420 		 * On at least the mcp23s17, INTCAP is only updated
421 		 * one byte at a time(INTCAPA and INTCAPB are
422 		 * not written to at the same time - only on a per-bank
423 		 * basis).
424 		 *
425 		 * INTF only contains the single bit that caused the
426 		 * interrupt per-bank.  On the mcp23s17, there is
427 		 * INTFA and INTFB.  If two pins are changed on the A
428 		 * side at the same time, INTF will only have one bit
429 		 * set.  If one pin on the A side and one pin on the B
430 		 * side are changed at the same time, INTF will have
431 		 * two bits set.  Thus, INTF can't be the only check
432 		 * to see if the input has changed.
433 		 */
434 
435 		intf_set = intf & BIT(i);
436 		if (i < 8 && intf_set)
437 			intcap_mask = 0x00FF;
438 		else if (i >= 8 && intf_set)
439 			intcap_mask = 0xFF00;
440 		else
441 			intcap_mask = 0x00;
442 
443 		intcap_changed = (intcap_mask &
444 			(intcap & BIT(i))) !=
445 			(intcap_mask & (BIT(i) & gpio_orig));
446 		gpio_set = BIT(i) & gpio;
447 		gpio_bit_changed = (BIT(i) & gpio_orig) !=
448 			(BIT(i) & gpio);
449 		defval_changed = (BIT(i) & intcon) &&
450 			((BIT(i) & gpio) !=
451 			(BIT(i) & defval));
452 
453 		if (((gpio_bit_changed || intcap_changed) &&
454 			(BIT(i) & mcp->irq_rise) && gpio_set) ||
455 		    ((gpio_bit_changed || intcap_changed) &&
456 			(BIT(i) & mcp->irq_fall) && !gpio_set) ||
457 		    defval_changed) {
458 			child_irq = irq_find_mapping(mcp->chip.irq.domain, i);
459 			handle_nested_irq(child_irq);
460 		}
461 	}
462 
463 	if (need_unmask) {
464 		mutex_lock(&mcp->lock);
465 		goto unlock;
466 	}
467 
468 	return IRQ_HANDLED;
469 
470 unlock:
471 	if (need_unmask)
472 		if (mcp_write(mcp, MCP_GPINTEN, gpinten))
473 			dev_err(mcp->chip.parent, "can't unmask GPINTEN\n");
474 
475 	mutex_unlock(&mcp->lock);
476 	return IRQ_HANDLED;
477 }
478 
mcp23s08_irq_mask(struct irq_data * data)479 static void mcp23s08_irq_mask(struct irq_data *data)
480 {
481 	struct gpio_chip *gc = irq_data_get_irq_chip_data(data);
482 	struct mcp23s08 *mcp = gpiochip_get_data(gc);
483 	unsigned int pos = irqd_to_hwirq(data);
484 
485 	mcp_set_bit(mcp, MCP_GPINTEN, pos, false);
486 	gpiochip_disable_irq(gc, pos);
487 }
488 
mcp23s08_irq_unmask(struct irq_data * data)489 static void mcp23s08_irq_unmask(struct irq_data *data)
490 {
491 	struct gpio_chip *gc = irq_data_get_irq_chip_data(data);
492 	struct mcp23s08 *mcp = gpiochip_get_data(gc);
493 	unsigned int pos = irqd_to_hwirq(data);
494 
495 	gpiochip_enable_irq(gc, pos);
496 	mcp_set_bit(mcp, MCP_GPINTEN, pos, true);
497 }
498 
mcp23s08_irq_set_type(struct irq_data * data,unsigned int type)499 static int mcp23s08_irq_set_type(struct irq_data *data, unsigned int type)
500 {
501 	struct gpio_chip *gc = irq_data_get_irq_chip_data(data);
502 	struct mcp23s08 *mcp = gpiochip_get_data(gc);
503 	unsigned int pos = irqd_to_hwirq(data);
504 
505 	if ((type & IRQ_TYPE_EDGE_BOTH) == IRQ_TYPE_EDGE_BOTH) {
506 		mcp_set_bit(mcp, MCP_INTCON, pos, false);
507 		mcp->irq_rise |= BIT(pos);
508 		mcp->irq_fall |= BIT(pos);
509 	} else if (type & IRQ_TYPE_EDGE_RISING) {
510 		mcp_set_bit(mcp, MCP_INTCON, pos, false);
511 		mcp->irq_rise |= BIT(pos);
512 		mcp->irq_fall &= ~BIT(pos);
513 	} else if (type & IRQ_TYPE_EDGE_FALLING) {
514 		mcp_set_bit(mcp, MCP_INTCON, pos, false);
515 		mcp->irq_rise &= ~BIT(pos);
516 		mcp->irq_fall |= BIT(pos);
517 	} else if (type & IRQ_TYPE_LEVEL_HIGH) {
518 		mcp_set_bit(mcp, MCP_INTCON, pos, true);
519 		mcp_set_bit(mcp, MCP_DEFVAL, pos, false);
520 	} else if (type & IRQ_TYPE_LEVEL_LOW) {
521 		mcp_set_bit(mcp, MCP_INTCON, pos, true);
522 		mcp_set_bit(mcp, MCP_DEFVAL, pos, true);
523 	} else
524 		return -EINVAL;
525 
526 	return 0;
527 }
528 
mcp23s08_irq_bus_lock(struct irq_data * data)529 static void mcp23s08_irq_bus_lock(struct irq_data *data)
530 {
531 	struct gpio_chip *gc = irq_data_get_irq_chip_data(data);
532 	struct mcp23s08 *mcp = gpiochip_get_data(gc);
533 
534 	mutex_lock(&mcp->lock);
535 	regcache_cache_only(mcp->regmap, true);
536 }
537 
mcp23s08_irq_bus_unlock(struct irq_data * data)538 static void mcp23s08_irq_bus_unlock(struct irq_data *data)
539 {
540 	struct gpio_chip *gc = irq_data_get_irq_chip_data(data);
541 	struct mcp23s08 *mcp = gpiochip_get_data(gc);
542 
543 	regcache_cache_only(mcp->regmap, false);
544 	regcache_sync(mcp->regmap);
545 
546 	mutex_unlock(&mcp->lock);
547 }
548 
mcp23s08_irq_setup(struct mcp23s08 * mcp)549 static int mcp23s08_irq_setup(struct mcp23s08 *mcp)
550 {
551 	struct gpio_chip *chip = &mcp->chip;
552 	int err;
553 	unsigned long irqflags = IRQF_ONESHOT | IRQF_SHARED;
554 
555 	if (mcp->irq_active_high)
556 		irqflags |= IRQF_TRIGGER_HIGH;
557 	else
558 		irqflags |= IRQF_TRIGGER_LOW;
559 
560 	err = devm_request_threaded_irq(chip->parent, mcp->irq, NULL,
561 					mcp23s08_irq,
562 					irqflags, dev_name(chip->parent), mcp);
563 	if (err != 0) {
564 		dev_err(chip->parent, "unable to request IRQ#%d: %d\n",
565 			mcp->irq, err);
566 		return err;
567 	}
568 
569 	return 0;
570 }
571 
mcp23s08_irq_print_chip(struct irq_data * d,struct seq_file * p)572 static void mcp23s08_irq_print_chip(struct irq_data *d, struct seq_file *p)
573 {
574 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
575 	struct mcp23s08 *mcp = gpiochip_get_data(gc);
576 
577 	seq_puts(p, dev_name(mcp->dev));
578 }
579 
580 static const struct irq_chip mcp23s08_irq_chip = {
581 	.irq_mask = mcp23s08_irq_mask,
582 	.irq_unmask = mcp23s08_irq_unmask,
583 	.irq_set_type = mcp23s08_irq_set_type,
584 	.irq_bus_lock = mcp23s08_irq_bus_lock,
585 	.irq_bus_sync_unlock = mcp23s08_irq_bus_unlock,
586 	.irq_print_chip = mcp23s08_irq_print_chip,
587 	.flags = IRQCHIP_IMMUTABLE,
588 	GPIOCHIP_IRQ_RESOURCE_HELPERS,
589 };
590 
591 /*----------------------------------------------------------------------*/
592 
mcp23s08_probe_one(struct mcp23s08 * mcp,struct device * dev,unsigned int addr,unsigned int type,unsigned int base)593 int mcp23s08_probe_one(struct mcp23s08 *mcp, struct device *dev,
594 		       unsigned int addr, unsigned int type, unsigned int base)
595 {
596 	int status, ret;
597 	bool mirror = false;
598 	bool open_drain = false;
599 
600 	mutex_init(&mcp->lock);
601 
602 	mcp->dev = dev;
603 	mcp->addr = addr;
604 
605 	mcp->irq_active_high = false;
606 
607 	mcp->chip.direction_input = mcp23s08_direction_input;
608 	mcp->chip.get = mcp23s08_get;
609 	mcp->chip.get_multiple = mcp23s08_get_multiple;
610 	mcp->chip.direction_output = mcp23s08_direction_output;
611 	mcp->chip.set = mcp23s08_set;
612 	mcp->chip.set_multiple = mcp23s08_set_multiple;
613 
614 	mcp->chip.base = base;
615 	mcp->chip.can_sleep = true;
616 	mcp->chip.parent = dev;
617 	mcp->chip.owner = THIS_MODULE;
618 
619 	mcp->reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
620 
621 	/* verify MCP_IOCON.SEQOP = 0, so sequential reads work,
622 	 * and MCP_IOCON.HAEN = 1, so we work with all chips.
623 	 */
624 
625 	ret = mcp_read(mcp, MCP_IOCON, &status);
626 	if (ret < 0)
627 		return dev_err_probe(dev, ret, "can't identify chip %d\n", addr);
628 
629 	mcp->irq_controller =
630 		device_property_read_bool(dev, "interrupt-controller");
631 	if (mcp->irq && mcp->irq_controller) {
632 		mcp->irq_active_high =
633 			device_property_read_bool(dev,
634 					      "microchip,irq-active-high");
635 
636 		mirror = device_property_read_bool(dev, "microchip,irq-mirror");
637 		open_drain = device_property_read_bool(dev, "drive-open-drain");
638 	}
639 
640 	if ((status & IOCON_SEQOP) || !(status & IOCON_HAEN) || mirror ||
641 	     mcp->irq_active_high || open_drain) {
642 		/* mcp23s17 has IOCON twice, make sure they are in sync */
643 		status &= ~(IOCON_SEQOP | (IOCON_SEQOP << 8));
644 		status |= IOCON_HAEN | (IOCON_HAEN << 8);
645 		if (mcp->irq_active_high)
646 			status |= IOCON_INTPOL | (IOCON_INTPOL << 8);
647 		else
648 			status &= ~(IOCON_INTPOL | (IOCON_INTPOL << 8));
649 
650 		if (mirror)
651 			status |= IOCON_MIRROR | (IOCON_MIRROR << 8);
652 
653 		if (open_drain)
654 			status |= IOCON_ODR | (IOCON_ODR << 8);
655 
656 		if (type == MCP_TYPE_S18 || type == MCP_TYPE_018)
657 			status |= IOCON_INTCC | (IOCON_INTCC << 8);
658 
659 		ret = mcp_write(mcp, MCP_IOCON, status);
660 		if (ret < 0)
661 			return dev_err_probe(dev, ret, "can't write IOCON %d\n", addr);
662 	}
663 
664 	if (mcp->irq && mcp->irq_controller) {
665 		struct gpio_irq_chip *girq = &mcp->chip.irq;
666 
667 		gpio_irq_chip_set_chip(girq, &mcp23s08_irq_chip);
668 		/* This will let us handle the parent IRQ in the driver */
669 		girq->parent_handler = NULL;
670 		girq->num_parents = 0;
671 		girq->parents = NULL;
672 		girq->default_type = IRQ_TYPE_NONE;
673 		girq->handler = handle_simple_irq;
674 		girq->threaded = true;
675 	}
676 
677 	ret = devm_gpiochip_add_data(dev, &mcp->chip, mcp);
678 	if (ret < 0)
679 		return dev_err_probe(dev, ret, "can't add GPIO chip\n");
680 
681 	mcp->pinctrl_desc.pctlops = &mcp_pinctrl_ops;
682 	mcp->pinctrl_desc.confops = &mcp_pinconf_ops;
683 	mcp->pinctrl_desc.npins = mcp->chip.ngpio;
684 	if (mcp->pinctrl_desc.npins == 8)
685 		mcp->pinctrl_desc.pins = mcp23x08_pins;
686 	else if (mcp->pinctrl_desc.npins == 16)
687 		mcp->pinctrl_desc.pins = mcp23x17_pins;
688 	mcp->pinctrl_desc.owner = THIS_MODULE;
689 
690 	mcp->pctldev = devm_pinctrl_register(dev, &mcp->pinctrl_desc, mcp);
691 	if (IS_ERR(mcp->pctldev))
692 		return dev_err_probe(dev, PTR_ERR(mcp->pctldev), "can't register controller\n");
693 
694 	if (mcp->irq) {
695 		ret = mcp23s08_irq_setup(mcp);
696 		if (ret)
697 			return dev_err_probe(dev, ret, "can't setup IRQ\n");
698 	}
699 
700 	return 0;
701 }
702 EXPORT_SYMBOL_GPL(mcp23s08_probe_one);
703 
704 MODULE_DESCRIPTION("MCP23S08 SPI/I2C GPIO driver");
705 MODULE_LICENSE("GPL");
706