xref: /linux/drivers/pinctrl/pinctrl-mcp23s08.c (revision f274fffbc28849848fd48379dbc83f10e1019270)
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 reg_default mcp23x08_defaults[] = {
48 	{.reg = MCP_IODIR,		.def = 0xff},
49 	{.reg = MCP_IPOL,		.def = 0x00},
50 	{.reg = MCP_GPINTEN,		.def = 0x00},
51 	{.reg = MCP_DEFVAL,		.def = 0x00},
52 	{.reg = MCP_INTCON,		.def = 0x00},
53 	{.reg = MCP_IOCON,		.def = 0x00},
54 	{.reg = MCP_GPPU,		.def = 0x00},
55 	{.reg = MCP_OLAT,		.def = 0x00},
56 };
57 
58 static const struct regmap_range mcp23x08_volatile_range = {
59 	.range_min = MCP_INTF,
60 	.range_max = MCP_GPIO,
61 };
62 
63 static const struct regmap_access_table mcp23x08_volatile_table = {
64 	.yes_ranges = &mcp23x08_volatile_range,
65 	.n_yes_ranges = 1,
66 };
67 
68 static const struct regmap_range mcp23x08_precious_range = {
69 	.range_min = MCP_GPIO,
70 	.range_max = MCP_GPIO,
71 };
72 
73 static const struct regmap_access_table mcp23x08_precious_table = {
74 	.yes_ranges = &mcp23x08_precious_range,
75 	.n_yes_ranges = 1,
76 };
77 
78 const struct regmap_config mcp23x08_regmap = {
79 	.reg_bits = 8,
80 	.val_bits = 8,
81 
82 	.reg_stride = 1,
83 	.volatile_table = &mcp23x08_volatile_table,
84 	.precious_table = &mcp23x08_precious_table,
85 	.reg_defaults = mcp23x08_defaults,
86 	.num_reg_defaults = ARRAY_SIZE(mcp23x08_defaults),
87 	.cache_type = REGCACHE_FLAT,
88 	.max_register = MCP_OLAT,
89 	.disable_locking = true, /* mcp->lock protects the regmap */
90 };
91 EXPORT_SYMBOL_GPL(mcp23x08_regmap);
92 
93 static const struct reg_default mcp23x17_defaults[] = {
94 	{.reg = MCP_IODIR << 1,		.def = 0xffff},
95 	{.reg = MCP_IPOL << 1,		.def = 0x0000},
96 	{.reg = MCP_GPINTEN << 1,	.def = 0x0000},
97 	{.reg = MCP_DEFVAL << 1,	.def = 0x0000},
98 	{.reg = MCP_INTCON << 1,	.def = 0x0000},
99 	{.reg = MCP_IOCON << 1,		.def = 0x0000},
100 	{.reg = MCP_GPPU << 1,		.def = 0x0000},
101 	{.reg = MCP_OLAT << 1,		.def = 0x0000},
102 };
103 
104 static const struct regmap_range mcp23x17_volatile_range = {
105 	.range_min = MCP_INTF << 1,
106 	.range_max = MCP_GPIO << 1,
107 };
108 
109 static const struct regmap_access_table mcp23x17_volatile_table = {
110 	.yes_ranges = &mcp23x17_volatile_range,
111 	.n_yes_ranges = 1,
112 };
113 
114 static const struct regmap_range mcp23x17_precious_range = {
115 	.range_min = MCP_INTCAP << 1,
116 	.range_max = MCP_GPIO << 1,
117 };
118 
119 static const struct regmap_access_table mcp23x17_precious_table = {
120 	.yes_ranges = &mcp23x17_precious_range,
121 	.n_yes_ranges = 1,
122 };
123 
124 const struct regmap_config mcp23x17_regmap = {
125 	.reg_bits = 8,
126 	.val_bits = 16,
127 
128 	.reg_stride = 2,
129 	.max_register = MCP_OLAT << 1,
130 	.volatile_table = &mcp23x17_volatile_table,
131 	.precious_table = &mcp23x17_precious_table,
132 	.reg_defaults = mcp23x17_defaults,
133 	.num_reg_defaults = ARRAY_SIZE(mcp23x17_defaults),
134 	.cache_type = REGCACHE_FLAT,
135 	.val_format_endian = REGMAP_ENDIAN_LITTLE,
136 	.disable_locking = true, /* mcp->lock protects the regmap */
137 };
138 EXPORT_SYMBOL_GPL(mcp23x17_regmap);
139 
mcp_read(struct mcp23s08 * mcp,unsigned int reg,unsigned int * val)140 static int mcp_read(struct mcp23s08 *mcp, unsigned int reg, unsigned int *val)
141 {
142 	return regmap_read(mcp->regmap, reg << mcp->reg_shift, val);
143 }
144 
mcp_write(struct mcp23s08 * mcp,unsigned int reg,unsigned int val)145 static int mcp_write(struct mcp23s08 *mcp, unsigned int reg, unsigned int val)
146 {
147 	return regmap_write(mcp->regmap, reg << mcp->reg_shift, val);
148 }
149 
mcp_update_bits(struct mcp23s08 * mcp,unsigned int reg,unsigned int mask,unsigned int val)150 static int mcp_update_bits(struct mcp23s08 *mcp, unsigned int reg,
151 			   unsigned int mask, unsigned int val)
152 {
153 	return regmap_update_bits(mcp->regmap, reg << mcp->reg_shift,
154 				  mask, val);
155 }
156 
mcp_set_bit(struct mcp23s08 * mcp,unsigned int reg,unsigned int pin,bool enabled)157 static int mcp_set_bit(struct mcp23s08 *mcp, unsigned int reg,
158 		       unsigned int pin, bool enabled)
159 {
160 	u16 mask = BIT(pin);
161 	return mcp_update_bits(mcp, reg, mask, enabled ? mask : 0);
162 }
163 
164 static const struct pinctrl_pin_desc mcp23x08_pins[] = {
165 	PINCTRL_PIN(0, "gpio0"),
166 	PINCTRL_PIN(1, "gpio1"),
167 	PINCTRL_PIN(2, "gpio2"),
168 	PINCTRL_PIN(3, "gpio3"),
169 	PINCTRL_PIN(4, "gpio4"),
170 	PINCTRL_PIN(5, "gpio5"),
171 	PINCTRL_PIN(6, "gpio6"),
172 	PINCTRL_PIN(7, "gpio7"),
173 };
174 
175 static const struct pinctrl_pin_desc mcp23x17_pins[] = {
176 	PINCTRL_PIN(0, "gpio0"),
177 	PINCTRL_PIN(1, "gpio1"),
178 	PINCTRL_PIN(2, "gpio2"),
179 	PINCTRL_PIN(3, "gpio3"),
180 	PINCTRL_PIN(4, "gpio4"),
181 	PINCTRL_PIN(5, "gpio5"),
182 	PINCTRL_PIN(6, "gpio6"),
183 	PINCTRL_PIN(7, "gpio7"),
184 	PINCTRL_PIN(8, "gpio8"),
185 	PINCTRL_PIN(9, "gpio9"),
186 	PINCTRL_PIN(10, "gpio10"),
187 	PINCTRL_PIN(11, "gpio11"),
188 	PINCTRL_PIN(12, "gpio12"),
189 	PINCTRL_PIN(13, "gpio13"),
190 	PINCTRL_PIN(14, "gpio14"),
191 	PINCTRL_PIN(15, "gpio15"),
192 };
193 
mcp_pinctrl_get_groups_count(struct pinctrl_dev * pctldev)194 static int mcp_pinctrl_get_groups_count(struct pinctrl_dev *pctldev)
195 {
196 	return 0;
197 }
198 
mcp_pinctrl_get_group_name(struct pinctrl_dev * pctldev,unsigned int group)199 static const char *mcp_pinctrl_get_group_name(struct pinctrl_dev *pctldev,
200 						unsigned int group)
201 {
202 	return NULL;
203 }
204 
mcp_pinctrl_get_group_pins(struct pinctrl_dev * pctldev,unsigned int group,const unsigned int ** pins,unsigned int * num_pins)205 static int mcp_pinctrl_get_group_pins(struct pinctrl_dev *pctldev,
206 					unsigned int group,
207 					const unsigned int **pins,
208 					unsigned int *num_pins)
209 {
210 	return -ENOTSUPP;
211 }
212 
213 static const struct pinctrl_ops mcp_pinctrl_ops = {
214 	.get_groups_count = mcp_pinctrl_get_groups_count,
215 	.get_group_name = mcp_pinctrl_get_group_name,
216 	.get_group_pins = mcp_pinctrl_get_group_pins,
217 #ifdef CONFIG_OF
218 	.dt_node_to_map = pinconf_generic_dt_node_to_map_pin,
219 	.dt_free_map = pinconf_generic_dt_free_map,
220 #endif
221 };
222 
mcp_pinconf_get(struct pinctrl_dev * pctldev,unsigned int pin,unsigned long * config)223 static int mcp_pinconf_get(struct pinctrl_dev *pctldev, unsigned int pin,
224 			      unsigned long *config)
225 {
226 	struct mcp23s08 *mcp = pinctrl_dev_get_drvdata(pctldev);
227 	enum pin_config_param param = pinconf_to_config_param(*config);
228 	unsigned int data, status;
229 	int ret;
230 
231 	switch (param) {
232 	case PIN_CONFIG_BIAS_PULL_UP:
233 		mutex_lock(&mcp->lock);
234 		ret = mcp_read(mcp, MCP_GPPU, &data);
235 		mutex_unlock(&mcp->lock);
236 		if (ret < 0)
237 			return ret;
238 		status = (data & BIT(pin)) ? 1 : 0;
239 		break;
240 	default:
241 		return -ENOTSUPP;
242 	}
243 
244 	*config = 0;
245 
246 	return status ? 0 : -EINVAL;
247 }
248 
mcp_pinconf_set(struct pinctrl_dev * pctldev,unsigned int pin,unsigned long * configs,unsigned int num_configs)249 static int mcp_pinconf_set(struct pinctrl_dev *pctldev, unsigned int pin,
250 			      unsigned long *configs, unsigned int num_configs)
251 {
252 	struct mcp23s08 *mcp = pinctrl_dev_get_drvdata(pctldev);
253 	enum pin_config_param param;
254 	u32 arg;
255 	int ret = 0;
256 	int i;
257 
258 	for (i = 0; i < num_configs; i++) {
259 		param = pinconf_to_config_param(configs[i]);
260 		arg = pinconf_to_config_argument(configs[i]);
261 
262 		switch (param) {
263 		case PIN_CONFIG_BIAS_PULL_UP:
264 			mutex_lock(&mcp->lock);
265 			ret = mcp_set_bit(mcp, MCP_GPPU, pin, arg);
266 			mutex_unlock(&mcp->lock);
267 			break;
268 		default:
269 			dev_dbg(mcp->dev, "Invalid config param %04x\n", param);
270 			return -ENOTSUPP;
271 		}
272 	}
273 
274 	return ret;
275 }
276 
277 static const struct pinconf_ops mcp_pinconf_ops = {
278 	.pin_config_get = mcp_pinconf_get,
279 	.pin_config_set = mcp_pinconf_set,
280 	.is_generic = true,
281 };
282 
283 /*----------------------------------------------------------------------*/
284 
mcp23s08_direction_input(struct gpio_chip * chip,unsigned offset)285 static int mcp23s08_direction_input(struct gpio_chip *chip, unsigned offset)
286 {
287 	struct mcp23s08	*mcp = gpiochip_get_data(chip);
288 	int status;
289 
290 	mutex_lock(&mcp->lock);
291 	status = mcp_set_bit(mcp, MCP_IODIR, offset, true);
292 	mutex_unlock(&mcp->lock);
293 
294 	return status;
295 }
296 
mcp23s08_get(struct gpio_chip * chip,unsigned offset)297 static int mcp23s08_get(struct gpio_chip *chip, unsigned offset)
298 {
299 	struct mcp23s08	*mcp = gpiochip_get_data(chip);
300 	int status, ret;
301 
302 	mutex_lock(&mcp->lock);
303 
304 	/* REVISIT reading this clears any IRQ ... */
305 	ret = mcp_read(mcp, MCP_GPIO, &status);
306 	if (ret < 0)
307 		status = 0;
308 	else {
309 		mcp->cached_gpio = status;
310 		status = !!(status & (1 << offset));
311 	}
312 
313 	mutex_unlock(&mcp->lock);
314 	return status;
315 }
316 
mcp23s08_get_multiple(struct gpio_chip * chip,unsigned long * mask,unsigned long * bits)317 static int mcp23s08_get_multiple(struct gpio_chip *chip,
318 				 unsigned long *mask, unsigned long *bits)
319 {
320 	struct mcp23s08 *mcp = gpiochip_get_data(chip);
321 	unsigned int status;
322 	int ret;
323 
324 	mutex_lock(&mcp->lock);
325 
326 	/* REVISIT reading this clears any IRQ ... */
327 	ret = mcp_read(mcp, MCP_GPIO, &status);
328 	if (ret < 0)
329 		status = 0;
330 	else {
331 		mcp->cached_gpio = status;
332 		*bits = status;
333 	}
334 
335 	mutex_unlock(&mcp->lock);
336 	return ret;
337 }
338 
__mcp23s08_set(struct mcp23s08 * mcp,unsigned mask,bool value)339 static int __mcp23s08_set(struct mcp23s08 *mcp, unsigned mask, bool value)
340 {
341 	return mcp_update_bits(mcp, MCP_OLAT, mask, value ? mask : 0);
342 }
343 
mcp23s08_set(struct gpio_chip * chip,unsigned offset,int value)344 static void mcp23s08_set(struct gpio_chip *chip, unsigned offset, int value)
345 {
346 	struct mcp23s08	*mcp = gpiochip_get_data(chip);
347 	unsigned mask = BIT(offset);
348 
349 	mutex_lock(&mcp->lock);
350 	__mcp23s08_set(mcp, mask, !!value);
351 	mutex_unlock(&mcp->lock);
352 }
353 
mcp23s08_set_multiple(struct gpio_chip * chip,unsigned long * mask,unsigned long * bits)354 static void mcp23s08_set_multiple(struct gpio_chip *chip,
355 				  unsigned long *mask, unsigned long *bits)
356 {
357 	struct mcp23s08	*mcp = gpiochip_get_data(chip);
358 
359 	mutex_lock(&mcp->lock);
360 	mcp_update_bits(mcp, MCP_OLAT, *mask, *bits);
361 	mutex_unlock(&mcp->lock);
362 }
363 
364 static int
mcp23s08_direction_output(struct gpio_chip * chip,unsigned offset,int value)365 mcp23s08_direction_output(struct gpio_chip *chip, unsigned offset, int value)
366 {
367 	struct mcp23s08	*mcp = gpiochip_get_data(chip);
368 	unsigned mask = BIT(offset);
369 	int status;
370 
371 	mutex_lock(&mcp->lock);
372 	status = __mcp23s08_set(mcp, mask, value);
373 	if (status == 0) {
374 		status = mcp_update_bits(mcp, MCP_IODIR, mask, 0);
375 	}
376 	mutex_unlock(&mcp->lock);
377 	return status;
378 }
379 
380 /*----------------------------------------------------------------------*/
mcp23s08_irq(int irq,void * data)381 static irqreturn_t mcp23s08_irq(int irq, void *data)
382 {
383 	struct mcp23s08 *mcp = data;
384 	int intcap, intcon, intf, i, gpio, gpio_orig, intcap_mask, defval, gpinten;
385 	unsigned long int enabled_interrupts;
386 	unsigned int child_irq;
387 	bool intf_set, intcap_changed, gpio_bit_changed,
388 		defval_changed, gpio_set;
389 
390 	mutex_lock(&mcp->lock);
391 	if (mcp_read(mcp, MCP_INTF, &intf))
392 		goto unlock;
393 
394 	if (intf == 0) {
395 		/* There is no interrupt pending */
396 		goto unlock;
397 	}
398 
399 	if (mcp_read(mcp, MCP_INTCAP, &intcap))
400 		goto unlock;
401 
402 	if (mcp_read(mcp, MCP_INTCON, &intcon))
403 		goto unlock;
404 
405 	if (mcp_read(mcp, MCP_GPINTEN, &gpinten))
406 		goto unlock;
407 
408 	if (mcp_read(mcp, MCP_DEFVAL, &defval))
409 		goto unlock;
410 
411 	/* This clears the interrupt(configurable on S18) */
412 	if (mcp_read(mcp, MCP_GPIO, &gpio))
413 		goto unlock;
414 
415 	gpio_orig = mcp->cached_gpio;
416 	mcp->cached_gpio = gpio;
417 	mutex_unlock(&mcp->lock);
418 
419 	dev_dbg(mcp->chip.parent,
420 		"intcap 0x%04X intf 0x%04X gpio_orig 0x%04X gpio 0x%04X\n",
421 		intcap, intf, gpio_orig, gpio);
422 
423 	enabled_interrupts = gpinten;
424 	for_each_set_bit(i, &enabled_interrupts, mcp->chip.ngpio) {
425 		/*
426 		 * We must check all of the inputs with enabled interrupts
427 		 * on the chip, otherwise we may not notice a change
428 		 * on more than one pin.
429 		 *
430 		 * On at least the mcp23s17, INTCAP is only updated
431 		 * one byte at a time(INTCAPA and INTCAPB are
432 		 * not written to at the same time - only on a per-bank
433 		 * basis).
434 		 *
435 		 * INTF only contains the single bit that caused the
436 		 * interrupt per-bank.  On the mcp23s17, there is
437 		 * INTFA and INTFB.  If two pins are changed on the A
438 		 * side at the same time, INTF will only have one bit
439 		 * set.  If one pin on the A side and one pin on the B
440 		 * side are changed at the same time, INTF will have
441 		 * two bits set.  Thus, INTF can't be the only check
442 		 * to see if the input has changed.
443 		 */
444 
445 		intf_set = intf & BIT(i);
446 		if (i < 8 && intf_set)
447 			intcap_mask = 0x00FF;
448 		else if (i >= 8 && intf_set)
449 			intcap_mask = 0xFF00;
450 		else
451 			intcap_mask = 0x00;
452 
453 		intcap_changed = (intcap_mask &
454 			(intcap & BIT(i))) !=
455 			(intcap_mask & (BIT(i) & gpio_orig));
456 		gpio_set = BIT(i) & gpio;
457 		gpio_bit_changed = (BIT(i) & gpio_orig) !=
458 			(BIT(i) & gpio);
459 		defval_changed = (BIT(i) & intcon) &&
460 			((BIT(i) & gpio) !=
461 			(BIT(i) & defval));
462 
463 		if (((gpio_bit_changed || intcap_changed) &&
464 			(BIT(i) & mcp->irq_rise) && gpio_set) ||
465 		    ((gpio_bit_changed || intcap_changed) &&
466 			(BIT(i) & mcp->irq_fall) && !gpio_set) ||
467 		    defval_changed) {
468 			child_irq = irq_find_mapping(mcp->chip.irq.domain, i);
469 			handle_nested_irq(child_irq);
470 		}
471 	}
472 
473 	return IRQ_HANDLED;
474 
475 unlock:
476 	mutex_unlock(&mcp->lock);
477 	return IRQ_HANDLED;
478 }
479 
mcp23s08_irq_mask(struct irq_data * data)480 static void mcp23s08_irq_mask(struct irq_data *data)
481 {
482 	struct gpio_chip *gc = irq_data_get_irq_chip_data(data);
483 	struct mcp23s08 *mcp = gpiochip_get_data(gc);
484 	unsigned int pos = irqd_to_hwirq(data);
485 
486 	mcp_set_bit(mcp, MCP_GPINTEN, pos, false);
487 	gpiochip_disable_irq(gc, pos);
488 }
489 
mcp23s08_irq_unmask(struct irq_data * data)490 static void mcp23s08_irq_unmask(struct irq_data *data)
491 {
492 	struct gpio_chip *gc = irq_data_get_irq_chip_data(data);
493 	struct mcp23s08 *mcp = gpiochip_get_data(gc);
494 	unsigned int pos = irqd_to_hwirq(data);
495 
496 	gpiochip_enable_irq(gc, pos);
497 	mcp_set_bit(mcp, MCP_GPINTEN, pos, true);
498 }
499 
mcp23s08_irq_set_type(struct irq_data * data,unsigned int type)500 static int mcp23s08_irq_set_type(struct irq_data *data, unsigned int type)
501 {
502 	struct gpio_chip *gc = irq_data_get_irq_chip_data(data);
503 	struct mcp23s08 *mcp = gpiochip_get_data(gc);
504 	unsigned int pos = irqd_to_hwirq(data);
505 
506 	if ((type & IRQ_TYPE_EDGE_BOTH) == IRQ_TYPE_EDGE_BOTH) {
507 		mcp_set_bit(mcp, MCP_INTCON, pos, false);
508 		mcp->irq_rise |= BIT(pos);
509 		mcp->irq_fall |= BIT(pos);
510 	} else if (type & IRQ_TYPE_EDGE_RISING) {
511 		mcp_set_bit(mcp, MCP_INTCON, pos, false);
512 		mcp->irq_rise |= BIT(pos);
513 		mcp->irq_fall &= ~BIT(pos);
514 	} else if (type & IRQ_TYPE_EDGE_FALLING) {
515 		mcp_set_bit(mcp, MCP_INTCON, pos, false);
516 		mcp->irq_rise &= ~BIT(pos);
517 		mcp->irq_fall |= BIT(pos);
518 	} else if (type & IRQ_TYPE_LEVEL_HIGH) {
519 		mcp_set_bit(mcp, MCP_INTCON, pos, true);
520 		mcp_set_bit(mcp, MCP_DEFVAL, pos, false);
521 	} else if (type & IRQ_TYPE_LEVEL_LOW) {
522 		mcp_set_bit(mcp, MCP_INTCON, pos, true);
523 		mcp_set_bit(mcp, MCP_DEFVAL, pos, true);
524 	} else
525 		return -EINVAL;
526 
527 	return 0;
528 }
529 
mcp23s08_irq_bus_lock(struct irq_data * data)530 static void mcp23s08_irq_bus_lock(struct irq_data *data)
531 {
532 	struct gpio_chip *gc = irq_data_get_irq_chip_data(data);
533 	struct mcp23s08 *mcp = gpiochip_get_data(gc);
534 
535 	mutex_lock(&mcp->lock);
536 	regcache_cache_only(mcp->regmap, true);
537 }
538 
mcp23s08_irq_bus_unlock(struct irq_data * data)539 static void mcp23s08_irq_bus_unlock(struct irq_data *data)
540 {
541 	struct gpio_chip *gc = irq_data_get_irq_chip_data(data);
542 	struct mcp23s08 *mcp = gpiochip_get_data(gc);
543 
544 	regcache_cache_only(mcp->regmap, false);
545 	regcache_sync(mcp->regmap);
546 
547 	mutex_unlock(&mcp->lock);
548 }
549 
mcp23s08_irq_setup(struct mcp23s08 * mcp)550 static int mcp23s08_irq_setup(struct mcp23s08 *mcp)
551 {
552 	struct gpio_chip *chip = &mcp->chip;
553 	int err;
554 	unsigned long irqflags = IRQF_ONESHOT | IRQF_SHARED;
555 
556 	if (mcp->irq_active_high)
557 		irqflags |= IRQF_TRIGGER_HIGH;
558 	else
559 		irqflags |= IRQF_TRIGGER_LOW;
560 
561 	err = devm_request_threaded_irq(chip->parent, mcp->irq, NULL,
562 					mcp23s08_irq,
563 					irqflags, dev_name(chip->parent), mcp);
564 	if (err != 0) {
565 		dev_err(chip->parent, "unable to request IRQ#%d: %d\n",
566 			mcp->irq, err);
567 		return err;
568 	}
569 
570 	return 0;
571 }
572 
mcp23s08_irq_print_chip(struct irq_data * d,struct seq_file * p)573 static void mcp23s08_irq_print_chip(struct irq_data *d, struct seq_file *p)
574 {
575 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
576 	struct mcp23s08 *mcp = gpiochip_get_data(gc);
577 
578 	seq_puts(p, dev_name(mcp->dev));
579 }
580 
581 static const struct irq_chip mcp23s08_irq_chip = {
582 	.irq_mask = mcp23s08_irq_mask,
583 	.irq_unmask = mcp23s08_irq_unmask,
584 	.irq_set_type = mcp23s08_irq_set_type,
585 	.irq_bus_lock = mcp23s08_irq_bus_lock,
586 	.irq_bus_sync_unlock = mcp23s08_irq_bus_unlock,
587 	.irq_print_chip = mcp23s08_irq_print_chip,
588 	.flags = IRQCHIP_IMMUTABLE,
589 	GPIOCHIP_IRQ_RESOURCE_HELPERS,
590 };
591 
592 /*----------------------------------------------------------------------*/
593 
mcp23s08_probe_one(struct mcp23s08 * mcp,struct device * dev,unsigned int addr,unsigned int type,unsigned int base)594 int mcp23s08_probe_one(struct mcp23s08 *mcp, struct device *dev,
595 		       unsigned int addr, unsigned int type, unsigned int base)
596 {
597 	int status, ret;
598 	bool mirror = false;
599 	bool open_drain = false;
600 
601 	mutex_init(&mcp->lock);
602 
603 	mcp->dev = dev;
604 	mcp->addr = addr;
605 
606 	mcp->irq_active_high = false;
607 
608 	mcp->chip.direction_input = mcp23s08_direction_input;
609 	mcp->chip.get = mcp23s08_get;
610 	mcp->chip.get_multiple = mcp23s08_get_multiple;
611 	mcp->chip.direction_output = mcp23s08_direction_output;
612 	mcp->chip.set = mcp23s08_set;
613 	mcp->chip.set_multiple = mcp23s08_set_multiple;
614 
615 	mcp->chip.base = base;
616 	mcp->chip.can_sleep = true;
617 	mcp->chip.parent = dev;
618 	mcp->chip.owner = THIS_MODULE;
619 
620 	mcp->reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
621 
622 	/* verify MCP_IOCON.SEQOP = 0, so sequential reads work,
623 	 * and MCP_IOCON.HAEN = 1, so we work with all chips.
624 	 */
625 
626 	ret = mcp_read(mcp, MCP_IOCON, &status);
627 	if (ret < 0)
628 		return dev_err_probe(dev, ret, "can't identify chip %d\n", addr);
629 
630 	mcp->irq_controller =
631 		device_property_read_bool(dev, "interrupt-controller");
632 	if (mcp->irq && mcp->irq_controller) {
633 		mcp->irq_active_high =
634 			device_property_read_bool(dev,
635 					      "microchip,irq-active-high");
636 
637 		mirror = device_property_read_bool(dev, "microchip,irq-mirror");
638 		open_drain = device_property_read_bool(dev, "drive-open-drain");
639 	}
640 
641 	if ((status & IOCON_SEQOP) || !(status & IOCON_HAEN) || mirror ||
642 	     mcp->irq_active_high || open_drain) {
643 		/* mcp23s17 has IOCON twice, make sure they are in sync */
644 		status &= ~(IOCON_SEQOP | (IOCON_SEQOP << 8));
645 		status |= IOCON_HAEN | (IOCON_HAEN << 8);
646 		if (mcp->irq_active_high)
647 			status |= IOCON_INTPOL | (IOCON_INTPOL << 8);
648 		else
649 			status &= ~(IOCON_INTPOL | (IOCON_INTPOL << 8));
650 
651 		if (mirror)
652 			status |= IOCON_MIRROR | (IOCON_MIRROR << 8);
653 
654 		if (open_drain)
655 			status |= IOCON_ODR | (IOCON_ODR << 8);
656 
657 		if (type == MCP_TYPE_S18 || type == MCP_TYPE_018)
658 			status |= IOCON_INTCC | (IOCON_INTCC << 8);
659 
660 		ret = mcp_write(mcp, MCP_IOCON, status);
661 		if (ret < 0)
662 			return dev_err_probe(dev, ret, "can't write IOCON %d\n", addr);
663 	}
664 
665 	if (mcp->irq && mcp->irq_controller) {
666 		struct gpio_irq_chip *girq = &mcp->chip.irq;
667 
668 		gpio_irq_chip_set_chip(girq, &mcp23s08_irq_chip);
669 		/* This will let us handle the parent IRQ in the driver */
670 		girq->parent_handler = NULL;
671 		girq->num_parents = 0;
672 		girq->parents = NULL;
673 		girq->default_type = IRQ_TYPE_NONE;
674 		girq->handler = handle_simple_irq;
675 		girq->threaded = true;
676 	}
677 
678 	ret = devm_gpiochip_add_data(dev, &mcp->chip, mcp);
679 	if (ret < 0)
680 		return dev_err_probe(dev, ret, "can't add GPIO chip\n");
681 
682 	mcp->pinctrl_desc.pctlops = &mcp_pinctrl_ops;
683 	mcp->pinctrl_desc.confops = &mcp_pinconf_ops;
684 	mcp->pinctrl_desc.npins = mcp->chip.ngpio;
685 	if (mcp->pinctrl_desc.npins == 8)
686 		mcp->pinctrl_desc.pins = mcp23x08_pins;
687 	else if (mcp->pinctrl_desc.npins == 16)
688 		mcp->pinctrl_desc.pins = mcp23x17_pins;
689 	mcp->pinctrl_desc.owner = THIS_MODULE;
690 
691 	mcp->pctldev = devm_pinctrl_register(dev, &mcp->pinctrl_desc, mcp);
692 	if (IS_ERR(mcp->pctldev))
693 		return dev_err_probe(dev, PTR_ERR(mcp->pctldev), "can't register controller\n");
694 
695 	if (mcp->irq) {
696 		ret = mcp23s08_irq_setup(mcp);
697 		if (ret)
698 			return dev_err_probe(dev, ret, "can't setup IRQ\n");
699 	}
700 
701 	return 0;
702 }
703 EXPORT_SYMBOL_GPL(mcp23s08_probe_one);
704 
705 MODULE_DESCRIPTION("MCP23S08 SPI/I2C GPIO driver");
706 MODULE_LICENSE("GPL");
707