xref: /linux/drivers/gpio/gpio-pca953x.c (revision 071bf69a0220253a44acb8b2a27f7a262b9a46bf)
1 /*
2  *  PCA953x 4/8/16/24/40 bit I/O ports
3  *
4  *  Copyright (C) 2005 Ben Gardner <bgardner@wabtec.com>
5  *  Copyright (C) 2007 Marvell International Ltd.
6  *
7  *  Derived from drivers/i2c/chips/pca9539.c
8  *
9  *  This program is free software; you can redistribute it and/or modify
10  *  it under the terms of the GNU General Public License as published by
11  *  the Free Software Foundation; version 2 of the License.
12  */
13 
14 #include <linux/module.h>
15 #include <linux/init.h>
16 #include <linux/gpio.h>
17 #include <linux/interrupt.h>
18 #include <linux/i2c.h>
19 #include <linux/platform_data/pca953x.h>
20 #include <linux/slab.h>
21 #include <asm/unaligned.h>
22 #include <linux/of_platform.h>
23 #include <linux/acpi.h>
24 
25 #define PCA953X_INPUT		0
26 #define PCA953X_OUTPUT		1
27 #define PCA953X_INVERT		2
28 #define PCA953X_DIRECTION	3
29 
30 #define REG_ADDR_AI		0x80
31 
32 #define PCA957X_IN		0
33 #define PCA957X_INVRT		1
34 #define PCA957X_BKEN		2
35 #define PCA957X_PUPD		3
36 #define PCA957X_CFG		4
37 #define PCA957X_OUT		5
38 #define PCA957X_MSK		6
39 #define PCA957X_INTS		7
40 
41 #define PCAL953X_IN_LATCH	34
42 #define PCAL953X_INT_MASK	37
43 #define PCAL953X_INT_STAT	38
44 
45 #define PCA_GPIO_MASK		0x00FF
46 #define PCA_INT			0x0100
47 #define PCA_PCAL		0x0200
48 #define PCA953X_TYPE		0x1000
49 #define PCA957X_TYPE		0x2000
50 #define PCA_TYPE_MASK		0xF000
51 
52 #define PCA_CHIP_TYPE(x)	((x) & PCA_TYPE_MASK)
53 
54 static const struct i2c_device_id pca953x_id[] = {
55 	{ "pca9505", 40 | PCA953X_TYPE | PCA_INT, },
56 	{ "pca9534", 8  | PCA953X_TYPE | PCA_INT, },
57 	{ "pca9535", 16 | PCA953X_TYPE | PCA_INT, },
58 	{ "pca9536", 4  | PCA953X_TYPE, },
59 	{ "pca9537", 4  | PCA953X_TYPE | PCA_INT, },
60 	{ "pca9538", 8  | PCA953X_TYPE | PCA_INT, },
61 	{ "pca9539", 16 | PCA953X_TYPE | PCA_INT, },
62 	{ "pca9554", 8  | PCA953X_TYPE | PCA_INT, },
63 	{ "pca9555", 16 | PCA953X_TYPE | PCA_INT, },
64 	{ "pca9556", 8  | PCA953X_TYPE, },
65 	{ "pca9557", 8  | PCA953X_TYPE, },
66 	{ "pca9574", 8  | PCA957X_TYPE | PCA_INT, },
67 	{ "pca9575", 16 | PCA957X_TYPE | PCA_INT, },
68 	{ "pca9698", 40 | PCA953X_TYPE, },
69 
70 	{ "pcal9555a", 16 | PCA953X_TYPE | PCA_INT | PCA_PCAL, },
71 
72 	{ "max7310", 8  | PCA953X_TYPE, },
73 	{ "max7312", 16 | PCA953X_TYPE | PCA_INT, },
74 	{ "max7313", 16 | PCA953X_TYPE | PCA_INT, },
75 	{ "max7315", 8  | PCA953X_TYPE | PCA_INT, },
76 	{ "pca6107", 8  | PCA953X_TYPE | PCA_INT, },
77 	{ "tca6408", 8  | PCA953X_TYPE | PCA_INT, },
78 	{ "tca6416", 16 | PCA953X_TYPE | PCA_INT, },
79 	{ "tca6424", 24 | PCA953X_TYPE | PCA_INT, },
80 	{ "tca9539", 16 | PCA953X_TYPE | PCA_INT, },
81 	{ "xra1202", 8  | PCA953X_TYPE },
82 	{ }
83 };
84 MODULE_DEVICE_TABLE(i2c, pca953x_id);
85 
86 static const struct acpi_device_id pca953x_acpi_ids[] = {
87 	{ "INT3491", 16 | PCA953X_TYPE | PCA_INT | PCA_PCAL, },
88 	{ }
89 };
90 MODULE_DEVICE_TABLE(acpi, pca953x_acpi_ids);
91 
92 #define MAX_BANK 5
93 #define BANK_SZ 8
94 
95 #define NBANK(chip) DIV_ROUND_UP(chip->gpio_chip.ngpio, BANK_SZ)
96 
97 struct pca953x_chip {
98 	unsigned gpio_start;
99 	u8 reg_output[MAX_BANK];
100 	u8 reg_direction[MAX_BANK];
101 	struct mutex i2c_lock;
102 
103 #ifdef CONFIG_GPIO_PCA953X_IRQ
104 	struct mutex irq_lock;
105 	u8 irq_mask[MAX_BANK];
106 	u8 irq_stat[MAX_BANK];
107 	u8 irq_trig_raise[MAX_BANK];
108 	u8 irq_trig_fall[MAX_BANK];
109 #endif
110 
111 	struct i2c_client *client;
112 	struct gpio_chip gpio_chip;
113 	const char *const *names;
114 	int	chip_type;
115 	unsigned long driver_data;
116 };
117 
118 static int pca953x_read_single(struct pca953x_chip *chip, int reg, u32 *val,
119 				int off)
120 {
121 	int ret;
122 	int bank_shift = fls((chip->gpio_chip.ngpio - 1) / BANK_SZ);
123 	int offset = off / BANK_SZ;
124 
125 	ret = i2c_smbus_read_byte_data(chip->client,
126 				(reg << bank_shift) + offset);
127 	*val = ret;
128 
129 	if (ret < 0) {
130 		dev_err(&chip->client->dev, "failed reading register\n");
131 		return ret;
132 	}
133 
134 	return 0;
135 }
136 
137 static int pca953x_write_single(struct pca953x_chip *chip, int reg, u32 val,
138 				int off)
139 {
140 	int ret;
141 	int bank_shift = fls((chip->gpio_chip.ngpio - 1) / BANK_SZ);
142 	int offset = off / BANK_SZ;
143 
144 	ret = i2c_smbus_write_byte_data(chip->client,
145 					(reg << bank_shift) + offset, val);
146 
147 	if (ret < 0) {
148 		dev_err(&chip->client->dev, "failed writing register\n");
149 		return ret;
150 	}
151 
152 	return 0;
153 }
154 
155 static int pca953x_write_regs(struct pca953x_chip *chip, int reg, u8 *val)
156 {
157 	int ret = 0;
158 
159 	if (chip->gpio_chip.ngpio <= 8)
160 		ret = i2c_smbus_write_byte_data(chip->client, reg, *val);
161 	else if (chip->gpio_chip.ngpio >= 24) {
162 		int bank_shift = fls((chip->gpio_chip.ngpio - 1) / BANK_SZ);
163 		ret = i2c_smbus_write_i2c_block_data(chip->client,
164 					(reg << bank_shift) | REG_ADDR_AI,
165 					NBANK(chip), val);
166 	} else {
167 		switch (chip->chip_type) {
168 		case PCA953X_TYPE: {
169 			__le16 word = cpu_to_le16(get_unaligned((u16 *)val));
170 
171 			ret = i2c_smbus_write_word_data(chip->client, reg << 1,
172 							(__force u16)word);
173 			break;
174 		}
175 		case PCA957X_TYPE:
176 			ret = i2c_smbus_write_byte_data(chip->client, reg << 1,
177 							val[0]);
178 			if (ret < 0)
179 				break;
180 			ret = i2c_smbus_write_byte_data(chip->client,
181 							(reg << 1) + 1,
182 							val[1]);
183 			break;
184 		}
185 	}
186 
187 	if (ret < 0) {
188 		dev_err(&chip->client->dev, "failed writing register\n");
189 		return ret;
190 	}
191 
192 	return 0;
193 }
194 
195 static int pca953x_read_regs(struct pca953x_chip *chip, int reg, u8 *val)
196 {
197 	int ret;
198 
199 	if (chip->gpio_chip.ngpio <= 8) {
200 		ret = i2c_smbus_read_byte_data(chip->client, reg);
201 		*val = ret;
202 	} else if (chip->gpio_chip.ngpio >= 24) {
203 		int bank_shift = fls((chip->gpio_chip.ngpio - 1) / BANK_SZ);
204 
205 		ret = i2c_smbus_read_i2c_block_data(chip->client,
206 					(reg << bank_shift) | REG_ADDR_AI,
207 					NBANK(chip), val);
208 	} else {
209 		ret = i2c_smbus_read_word_data(chip->client, reg << 1);
210 		val[0] = (u16)ret & 0xFF;
211 		val[1] = (u16)ret >> 8;
212 	}
213 	if (ret < 0) {
214 		dev_err(&chip->client->dev, "failed reading register\n");
215 		return ret;
216 	}
217 
218 	return 0;
219 }
220 
221 static int pca953x_gpio_direction_input(struct gpio_chip *gc, unsigned off)
222 {
223 	struct pca953x_chip *chip = gpiochip_get_data(gc);
224 	u8 reg_val;
225 	int ret, offset = 0;
226 
227 	mutex_lock(&chip->i2c_lock);
228 	reg_val = chip->reg_direction[off / BANK_SZ] | (1u << (off % BANK_SZ));
229 
230 	switch (chip->chip_type) {
231 	case PCA953X_TYPE:
232 		offset = PCA953X_DIRECTION;
233 		break;
234 	case PCA957X_TYPE:
235 		offset = PCA957X_CFG;
236 		break;
237 	}
238 	ret = pca953x_write_single(chip, offset, reg_val, off);
239 	if (ret)
240 		goto exit;
241 
242 	chip->reg_direction[off / BANK_SZ] = reg_val;
243 exit:
244 	mutex_unlock(&chip->i2c_lock);
245 	return ret;
246 }
247 
248 static int pca953x_gpio_direction_output(struct gpio_chip *gc,
249 		unsigned off, int val)
250 {
251 	struct pca953x_chip *chip = gpiochip_get_data(gc);
252 	u8 reg_val;
253 	int ret, offset = 0;
254 
255 	mutex_lock(&chip->i2c_lock);
256 	/* set output level */
257 	if (val)
258 		reg_val = chip->reg_output[off / BANK_SZ]
259 			| (1u << (off % BANK_SZ));
260 	else
261 		reg_val = chip->reg_output[off / BANK_SZ]
262 			& ~(1u << (off % BANK_SZ));
263 
264 	switch (chip->chip_type) {
265 	case PCA953X_TYPE:
266 		offset = PCA953X_OUTPUT;
267 		break;
268 	case PCA957X_TYPE:
269 		offset = PCA957X_OUT;
270 		break;
271 	}
272 	ret = pca953x_write_single(chip, offset, reg_val, off);
273 	if (ret)
274 		goto exit;
275 
276 	chip->reg_output[off / BANK_SZ] = reg_val;
277 
278 	/* then direction */
279 	reg_val = chip->reg_direction[off / BANK_SZ] & ~(1u << (off % BANK_SZ));
280 	switch (chip->chip_type) {
281 	case PCA953X_TYPE:
282 		offset = PCA953X_DIRECTION;
283 		break;
284 	case PCA957X_TYPE:
285 		offset = PCA957X_CFG;
286 		break;
287 	}
288 	ret = pca953x_write_single(chip, offset, reg_val, off);
289 	if (ret)
290 		goto exit;
291 
292 	chip->reg_direction[off / BANK_SZ] = reg_val;
293 exit:
294 	mutex_unlock(&chip->i2c_lock);
295 	return ret;
296 }
297 
298 static int pca953x_gpio_get_value(struct gpio_chip *gc, unsigned off)
299 {
300 	struct pca953x_chip *chip = gpiochip_get_data(gc);
301 	u32 reg_val;
302 	int ret, offset = 0;
303 
304 	mutex_lock(&chip->i2c_lock);
305 	switch (chip->chip_type) {
306 	case PCA953X_TYPE:
307 		offset = PCA953X_INPUT;
308 		break;
309 	case PCA957X_TYPE:
310 		offset = PCA957X_IN;
311 		break;
312 	}
313 	ret = pca953x_read_single(chip, offset, &reg_val, off);
314 	mutex_unlock(&chip->i2c_lock);
315 	if (ret < 0) {
316 		/* NOTE:  diagnostic already emitted; that's all we should
317 		 * do unless gpio_*_value_cansleep() calls become different
318 		 * from their nonsleeping siblings (and report faults).
319 		 */
320 		return 0;
321 	}
322 
323 	return (reg_val & (1u << (off % BANK_SZ))) ? 1 : 0;
324 }
325 
326 static void pca953x_gpio_set_value(struct gpio_chip *gc, unsigned off, int val)
327 {
328 	struct pca953x_chip *chip = gpiochip_get_data(gc);
329 	u8 reg_val;
330 	int ret, offset = 0;
331 
332 	mutex_lock(&chip->i2c_lock);
333 	if (val)
334 		reg_val = chip->reg_output[off / BANK_SZ]
335 			| (1u << (off % BANK_SZ));
336 	else
337 		reg_val = chip->reg_output[off / BANK_SZ]
338 			& ~(1u << (off % BANK_SZ));
339 
340 	switch (chip->chip_type) {
341 	case PCA953X_TYPE:
342 		offset = PCA953X_OUTPUT;
343 		break;
344 	case PCA957X_TYPE:
345 		offset = PCA957X_OUT;
346 		break;
347 	}
348 	ret = pca953x_write_single(chip, offset, reg_val, off);
349 	if (ret)
350 		goto exit;
351 
352 	chip->reg_output[off / BANK_SZ] = reg_val;
353 exit:
354 	mutex_unlock(&chip->i2c_lock);
355 }
356 
357 static void pca953x_gpio_set_multiple(struct gpio_chip *gc,
358 		unsigned long *mask, unsigned long *bits)
359 {
360 	struct pca953x_chip *chip = gpiochip_get_data(gc);
361 	u8 reg_val[MAX_BANK];
362 	int ret, offset = 0;
363 	int bank_shift = fls((chip->gpio_chip.ngpio - 1) / BANK_SZ);
364 	int bank;
365 
366 	switch (chip->chip_type) {
367 	case PCA953X_TYPE:
368 		offset = PCA953X_OUTPUT;
369 		break;
370 	case PCA957X_TYPE:
371 		offset = PCA957X_OUT;
372 		break;
373 	}
374 
375 	memcpy(reg_val, chip->reg_output, NBANK(chip));
376 	mutex_lock(&chip->i2c_lock);
377 	for(bank=0; bank<NBANK(chip); bank++) {
378 		unsigned bankmask = mask[bank / sizeof(*mask)] >>
379 				    ((bank % sizeof(*mask)) * 8);
380 		if(bankmask) {
381 			unsigned bankval  = bits[bank / sizeof(*bits)] >>
382 					    ((bank % sizeof(*bits)) * 8);
383 			reg_val[bank] = (reg_val[bank] & ~bankmask) | bankval;
384 		}
385 	}
386 	ret = i2c_smbus_write_i2c_block_data(chip->client, offset << bank_shift, NBANK(chip), reg_val);
387 	if (ret)
388 		goto exit;
389 
390 	memcpy(chip->reg_output, reg_val, NBANK(chip));
391 exit:
392 	mutex_unlock(&chip->i2c_lock);
393 }
394 
395 static void pca953x_setup_gpio(struct pca953x_chip *chip, int gpios)
396 {
397 	struct gpio_chip *gc;
398 
399 	gc = &chip->gpio_chip;
400 
401 	gc->direction_input  = pca953x_gpio_direction_input;
402 	gc->direction_output = pca953x_gpio_direction_output;
403 	gc->get = pca953x_gpio_get_value;
404 	gc->set = pca953x_gpio_set_value;
405 	gc->set_multiple = pca953x_gpio_set_multiple;
406 	gc->can_sleep = true;
407 
408 	gc->base = chip->gpio_start;
409 	gc->ngpio = gpios;
410 	gc->label = chip->client->name;
411 	gc->parent = &chip->client->dev;
412 	gc->owner = THIS_MODULE;
413 	gc->names = chip->names;
414 }
415 
416 #ifdef CONFIG_GPIO_PCA953X_IRQ
417 static void pca953x_irq_mask(struct irq_data *d)
418 {
419 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
420 	struct pca953x_chip *chip = gpiochip_get_data(gc);
421 
422 	chip->irq_mask[d->hwirq / BANK_SZ] &= ~(1 << (d->hwirq % BANK_SZ));
423 }
424 
425 static void pca953x_irq_unmask(struct irq_data *d)
426 {
427 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
428 	struct pca953x_chip *chip = gpiochip_get_data(gc);
429 
430 	chip->irq_mask[d->hwirq / BANK_SZ] |= 1 << (d->hwirq % BANK_SZ);
431 }
432 
433 static void pca953x_irq_bus_lock(struct irq_data *d)
434 {
435 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
436 	struct pca953x_chip *chip = gpiochip_get_data(gc);
437 
438 	mutex_lock(&chip->irq_lock);
439 }
440 
441 static void pca953x_irq_bus_sync_unlock(struct irq_data *d)
442 {
443 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
444 	struct pca953x_chip *chip = gpiochip_get_data(gc);
445 	u8 new_irqs;
446 	int level, i;
447 	u8 invert_irq_mask[MAX_BANK];
448 
449 	if (chip->driver_data & PCA_PCAL) {
450 		/* Enable latch on interrupt-enabled inputs */
451 		pca953x_write_regs(chip, PCAL953X_IN_LATCH, chip->irq_mask);
452 
453 		for (i = 0; i < NBANK(chip); i++)
454 			invert_irq_mask[i] = ~chip->irq_mask[i];
455 
456 		/* Unmask enabled interrupts */
457 		pca953x_write_regs(chip, PCAL953X_INT_MASK, invert_irq_mask);
458 	}
459 
460 	/* Look for any newly setup interrupt */
461 	for (i = 0; i < NBANK(chip); i++) {
462 		new_irqs = chip->irq_trig_fall[i] | chip->irq_trig_raise[i];
463 		new_irqs &= ~chip->reg_direction[i];
464 
465 		while (new_irqs) {
466 			level = __ffs(new_irqs);
467 			pca953x_gpio_direction_input(&chip->gpio_chip,
468 							level + (BANK_SZ * i));
469 			new_irqs &= ~(1 << level);
470 		}
471 	}
472 
473 	mutex_unlock(&chip->irq_lock);
474 }
475 
476 static int pca953x_irq_set_type(struct irq_data *d, unsigned int type)
477 {
478 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
479 	struct pca953x_chip *chip = gpiochip_get_data(gc);
480 	int bank_nb = d->hwirq / BANK_SZ;
481 	u8 mask = 1 << (d->hwirq % BANK_SZ);
482 
483 	if (!(type & IRQ_TYPE_EDGE_BOTH)) {
484 		dev_err(&chip->client->dev, "irq %d: unsupported type %d\n",
485 			d->irq, type);
486 		return -EINVAL;
487 	}
488 
489 	if (type & IRQ_TYPE_EDGE_FALLING)
490 		chip->irq_trig_fall[bank_nb] |= mask;
491 	else
492 		chip->irq_trig_fall[bank_nb] &= ~mask;
493 
494 	if (type & IRQ_TYPE_EDGE_RISING)
495 		chip->irq_trig_raise[bank_nb] |= mask;
496 	else
497 		chip->irq_trig_raise[bank_nb] &= ~mask;
498 
499 	return 0;
500 }
501 
502 static struct irq_chip pca953x_irq_chip = {
503 	.name			= "pca953x",
504 	.irq_mask		= pca953x_irq_mask,
505 	.irq_unmask		= pca953x_irq_unmask,
506 	.irq_bus_lock		= pca953x_irq_bus_lock,
507 	.irq_bus_sync_unlock	= pca953x_irq_bus_sync_unlock,
508 	.irq_set_type		= pca953x_irq_set_type,
509 };
510 
511 static bool pca953x_irq_pending(struct pca953x_chip *chip, u8 *pending)
512 {
513 	u8 cur_stat[MAX_BANK];
514 	u8 old_stat[MAX_BANK];
515 	bool pending_seen = false;
516 	bool trigger_seen = false;
517 	u8 trigger[MAX_BANK];
518 	int ret, i, offset = 0;
519 
520 	if (chip->driver_data & PCA_PCAL) {
521 		/* Read the current interrupt status from the device */
522 		ret = pca953x_read_regs(chip, PCAL953X_INT_STAT, trigger);
523 		if (ret)
524 			return false;
525 
526 		/* Check latched inputs and clear interrupt status */
527 		ret = pca953x_read_regs(chip, PCA953X_INPUT, cur_stat);
528 		if (ret)
529 			return false;
530 
531 		for (i = 0; i < NBANK(chip); i++) {
532 			/* Apply filter for rising/falling edge selection */
533 			pending[i] = (~cur_stat[i] & chip->irq_trig_fall[i]) |
534 				(cur_stat[i] & chip->irq_trig_raise[i]);
535 			pending[i] &= trigger[i];
536 			if (pending[i])
537 				pending_seen = true;
538 		}
539 
540 		return pending_seen;
541 	}
542 
543 	switch (chip->chip_type) {
544 	case PCA953X_TYPE:
545 		offset = PCA953X_INPUT;
546 		break;
547 	case PCA957X_TYPE:
548 		offset = PCA957X_IN;
549 		break;
550 	}
551 	ret = pca953x_read_regs(chip, offset, cur_stat);
552 	if (ret)
553 		return false;
554 
555 	/* Remove output pins from the equation */
556 	for (i = 0; i < NBANK(chip); i++)
557 		cur_stat[i] &= chip->reg_direction[i];
558 
559 	memcpy(old_stat, chip->irq_stat, NBANK(chip));
560 
561 	for (i = 0; i < NBANK(chip); i++) {
562 		trigger[i] = (cur_stat[i] ^ old_stat[i]) & chip->irq_mask[i];
563 		if (trigger[i])
564 			trigger_seen = true;
565 	}
566 
567 	if (!trigger_seen)
568 		return false;
569 
570 	memcpy(chip->irq_stat, cur_stat, NBANK(chip));
571 
572 	for (i = 0; i < NBANK(chip); i++) {
573 		pending[i] = (old_stat[i] & chip->irq_trig_fall[i]) |
574 			(cur_stat[i] & chip->irq_trig_raise[i]);
575 		pending[i] &= trigger[i];
576 		if (pending[i])
577 			pending_seen = true;
578 	}
579 
580 	return pending_seen;
581 }
582 
583 static irqreturn_t pca953x_irq_handler(int irq, void *devid)
584 {
585 	struct pca953x_chip *chip = devid;
586 	u8 pending[MAX_BANK];
587 	u8 level;
588 	unsigned nhandled = 0;
589 	int i;
590 
591 	if (!pca953x_irq_pending(chip, pending))
592 		return IRQ_NONE;
593 
594 	for (i = 0; i < NBANK(chip); i++) {
595 		while (pending[i]) {
596 			level = __ffs(pending[i]);
597 			handle_nested_irq(irq_find_mapping(chip->gpio_chip.irqdomain,
598 							level + (BANK_SZ * i)));
599 			pending[i] &= ~(1 << level);
600 			nhandled++;
601 		}
602 	}
603 
604 	return (nhandled > 0) ? IRQ_HANDLED : IRQ_NONE;
605 }
606 
607 static int pca953x_irq_setup(struct pca953x_chip *chip,
608 			     int irq_base)
609 {
610 	struct i2c_client *client = chip->client;
611 	int ret, i, offset = 0;
612 
613 	if (client->irq && irq_base != -1
614 			&& (chip->driver_data & PCA_INT)) {
615 
616 		switch (chip->chip_type) {
617 		case PCA953X_TYPE:
618 			offset = PCA953X_INPUT;
619 			break;
620 		case PCA957X_TYPE:
621 			offset = PCA957X_IN;
622 			break;
623 		}
624 		ret = pca953x_read_regs(chip, offset, chip->irq_stat);
625 		if (ret)
626 			return ret;
627 
628 		/*
629 		 * There is no way to know which GPIO line generated the
630 		 * interrupt.  We have to rely on the previous read for
631 		 * this purpose.
632 		 */
633 		for (i = 0; i < NBANK(chip); i++)
634 			chip->irq_stat[i] &= chip->reg_direction[i];
635 		mutex_init(&chip->irq_lock);
636 
637 		ret = devm_request_threaded_irq(&client->dev,
638 					client->irq,
639 					   NULL,
640 					   pca953x_irq_handler,
641 					   IRQF_TRIGGER_LOW | IRQF_ONESHOT |
642 						   IRQF_SHARED,
643 					   dev_name(&client->dev), chip);
644 		if (ret) {
645 			dev_err(&client->dev, "failed to request irq %d\n",
646 				client->irq);
647 			return ret;
648 		}
649 
650 		ret =  gpiochip_irqchip_add(&chip->gpio_chip,
651 					    &pca953x_irq_chip,
652 					    irq_base,
653 					    handle_simple_irq,
654 					    IRQ_TYPE_NONE);
655 		if (ret) {
656 			dev_err(&client->dev,
657 				"could not connect irqchip to gpiochip\n");
658 			return ret;
659 		}
660 
661 		gpiochip_set_chained_irqchip(&chip->gpio_chip,
662 					     &pca953x_irq_chip,
663 					     client->irq, NULL);
664 	}
665 
666 	return 0;
667 }
668 
669 #else /* CONFIG_GPIO_PCA953X_IRQ */
670 static int pca953x_irq_setup(struct pca953x_chip *chip,
671 			     int irq_base)
672 {
673 	struct i2c_client *client = chip->client;
674 
675 	if (irq_base != -1 && (chip->driver_data & PCA_INT))
676 		dev_warn(&client->dev, "interrupt support not compiled in\n");
677 
678 	return 0;
679 }
680 #endif
681 
682 static int device_pca953x_init(struct pca953x_chip *chip, u32 invert)
683 {
684 	int ret;
685 	u8 val[MAX_BANK];
686 
687 	ret = pca953x_read_regs(chip, PCA953X_OUTPUT, chip->reg_output);
688 	if (ret)
689 		goto out;
690 
691 	ret = pca953x_read_regs(chip, PCA953X_DIRECTION,
692 			       chip->reg_direction);
693 	if (ret)
694 		goto out;
695 
696 	/* set platform specific polarity inversion */
697 	if (invert)
698 		memset(val, 0xFF, NBANK(chip));
699 	else
700 		memset(val, 0, NBANK(chip));
701 
702 	ret = pca953x_write_regs(chip, PCA953X_INVERT, val);
703 out:
704 	return ret;
705 }
706 
707 static int device_pca957x_init(struct pca953x_chip *chip, u32 invert)
708 {
709 	int ret;
710 	u8 val[MAX_BANK];
711 
712 	ret = pca953x_read_regs(chip, PCA957X_OUT, chip->reg_output);
713 	if (ret)
714 		goto out;
715 	ret = pca953x_read_regs(chip, PCA957X_CFG, chip->reg_direction);
716 	if (ret)
717 		goto out;
718 
719 	/* set platform specific polarity inversion */
720 	if (invert)
721 		memset(val, 0xFF, NBANK(chip));
722 	else
723 		memset(val, 0, NBANK(chip));
724 	ret = pca953x_write_regs(chip, PCA957X_INVRT, val);
725 	if (ret)
726 		goto out;
727 
728 	/* To enable register 6, 7 to control pull up and pull down */
729 	memset(val, 0x02, NBANK(chip));
730 	ret = pca953x_write_regs(chip, PCA957X_BKEN, val);
731 	if (ret)
732 		goto out;
733 
734 	return 0;
735 out:
736 	return ret;
737 }
738 
739 static const struct of_device_id pca953x_dt_ids[];
740 
741 static int pca953x_probe(struct i2c_client *client,
742 				   const struct i2c_device_id *id)
743 {
744 	struct pca953x_platform_data *pdata;
745 	struct pca953x_chip *chip;
746 	int irq_base = 0;
747 	int ret;
748 	u32 invert = 0;
749 
750 	chip = devm_kzalloc(&client->dev,
751 			sizeof(struct pca953x_chip), GFP_KERNEL);
752 	if (chip == NULL)
753 		return -ENOMEM;
754 
755 	pdata = dev_get_platdata(&client->dev);
756 	if (pdata) {
757 		irq_base = pdata->irq_base;
758 		chip->gpio_start = pdata->gpio_base;
759 		invert = pdata->invert;
760 		chip->names = pdata->names;
761 	} else {
762 		chip->gpio_start = -1;
763 		irq_base = 0;
764 	}
765 
766 	chip->client = client;
767 
768 	if (id) {
769 		chip->driver_data = id->driver_data;
770 	} else {
771 		const struct acpi_device_id *id;
772 		const struct of_device_id *match;
773 
774 		match = of_match_device(pca953x_dt_ids, &client->dev);
775 		if (match) {
776 			chip->driver_data = (int)(uintptr_t)match->data;
777 		} else {
778 			id = acpi_match_device(pca953x_acpi_ids, &client->dev);
779 			if (!id)
780 				return -ENODEV;
781 
782 			chip->driver_data = id->driver_data;
783 		}
784 	}
785 
786 	chip->chip_type = PCA_CHIP_TYPE(chip->driver_data);
787 
788 	mutex_init(&chip->i2c_lock);
789 
790 	/* initialize cached registers from their original values.
791 	 * we can't share this chip with another i2c master.
792 	 */
793 	pca953x_setup_gpio(chip, chip->driver_data & PCA_GPIO_MASK);
794 
795 	if (chip->chip_type == PCA953X_TYPE)
796 		ret = device_pca953x_init(chip, invert);
797 	else
798 		ret = device_pca957x_init(chip, invert);
799 	if (ret)
800 		return ret;
801 
802 	ret = devm_gpiochip_add_data(&client->dev, &chip->gpio_chip, chip);
803 	if (ret)
804 		return ret;
805 
806 	ret = pca953x_irq_setup(chip, irq_base);
807 	if (ret)
808 		return ret;
809 
810 	if (pdata && pdata->setup) {
811 		ret = pdata->setup(client, chip->gpio_chip.base,
812 				chip->gpio_chip.ngpio, pdata->context);
813 		if (ret < 0)
814 			dev_warn(&client->dev, "setup failed, %d\n", ret);
815 	}
816 
817 	i2c_set_clientdata(client, chip);
818 	return 0;
819 }
820 
821 static int pca953x_remove(struct i2c_client *client)
822 {
823 	struct pca953x_platform_data *pdata = dev_get_platdata(&client->dev);
824 	struct pca953x_chip *chip = i2c_get_clientdata(client);
825 	int ret;
826 
827 	if (pdata && pdata->teardown) {
828 		ret = pdata->teardown(client, chip->gpio_chip.base,
829 				chip->gpio_chip.ngpio, pdata->context);
830 		if (ret < 0) {
831 			dev_err(&client->dev, "%s failed, %d\n",
832 					"teardown", ret);
833 			return ret;
834 		}
835 	}
836 
837 	return 0;
838 }
839 
840 /* convenience to stop overlong match-table lines */
841 #define OF_953X(__nrgpio, __int) (void *)(__nrgpio | PCA953X_TYPE | __int)
842 #define OF_957X(__nrgpio, __int) (void *)(__nrgpio | PCA957X_TYPE | __int)
843 
844 static const struct of_device_id pca953x_dt_ids[] = {
845 	{ .compatible = "nxp,pca9505", .data = OF_953X(40, PCA_INT), },
846 	{ .compatible = "nxp,pca9534", .data = OF_953X( 8, PCA_INT), },
847 	{ .compatible = "nxp,pca9535", .data = OF_953X(16, PCA_INT), },
848 	{ .compatible = "nxp,pca9536", .data = OF_953X( 4, 0), },
849 	{ .compatible = "nxp,pca9537", .data = OF_953X( 4, PCA_INT), },
850 	{ .compatible = "nxp,pca9538", .data = OF_953X( 8, PCA_INT), },
851 	{ .compatible = "nxp,pca9539", .data = OF_953X(16, PCA_INT), },
852 	{ .compatible = "nxp,pca9554", .data = OF_953X( 8, PCA_INT), },
853 	{ .compatible = "nxp,pca9555", .data = OF_953X(16, PCA_INT), },
854 	{ .compatible = "nxp,pca9556", .data = OF_953X( 8, 0), },
855 	{ .compatible = "nxp,pca9557", .data = OF_953X( 8, 0), },
856 	{ .compatible = "nxp,pca9574", .data = OF_957X( 8, PCA_INT), },
857 	{ .compatible = "nxp,pca9575", .data = OF_957X(16, PCA_INT), },
858 	{ .compatible = "nxp,pca9698", .data = OF_953X(40, 0), },
859 
860 	{ .compatible = "maxim,max7310", .data = OF_953X( 8, 0), },
861 	{ .compatible = "maxim,max7312", .data = OF_953X(16, PCA_INT), },
862 	{ .compatible = "maxim,max7313", .data = OF_953X(16, PCA_INT), },
863 	{ .compatible = "maxim,max7315", .data = OF_953X( 8, PCA_INT), },
864 
865 	{ .compatible = "ti,pca6107", .data = OF_953X( 8, PCA_INT), },
866 	{ .compatible = "ti,pca9536", .data = OF_953X( 4, 0), },
867 	{ .compatible = "ti,tca6408", .data = OF_953X( 8, PCA_INT), },
868 	{ .compatible = "ti,tca6416", .data = OF_953X(16, PCA_INT), },
869 	{ .compatible = "ti,tca6424", .data = OF_953X(24, PCA_INT), },
870 
871 	{ .compatible = "onsemi,pca9654", .data = OF_953X( 8, PCA_INT), },
872 
873 	{ .compatible = "exar,xra1202", .data = OF_953X( 8, 0), },
874 	{ }
875 };
876 
877 MODULE_DEVICE_TABLE(of, pca953x_dt_ids);
878 
879 static struct i2c_driver pca953x_driver = {
880 	.driver = {
881 		.name	= "pca953x",
882 		.of_match_table = pca953x_dt_ids,
883 		.acpi_match_table = ACPI_PTR(pca953x_acpi_ids),
884 	},
885 	.probe		= pca953x_probe,
886 	.remove		= pca953x_remove,
887 	.id_table	= pca953x_id,
888 };
889 
890 static int __init pca953x_init(void)
891 {
892 	return i2c_add_driver(&pca953x_driver);
893 }
894 /* register after i2c postcore initcall and before
895  * subsys initcalls that may rely on these GPIOs
896  */
897 subsys_initcall(pca953x_init);
898 
899 static void __exit pca953x_exit(void)
900 {
901 	i2c_del_driver(&pca953x_driver);
902 }
903 module_exit(pca953x_exit);
904 
905 MODULE_AUTHOR("eric miao <eric.miao@marvell.com>");
906 MODULE_DESCRIPTION("GPIO expander driver for PCA953x");
907 MODULE_LICENSE("GPL");
908