xref: /openbmc/linux/drivers/gpio/gpio-pca953x.c (revision 133f9794)
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/acpi.h>
15 #include <linux/gpio.h>
16 #include <linux/gpio/consumer.h>
17 #include <linux/i2c.h>
18 #include <linux/init.h>
19 #include <linux/interrupt.h>
20 #include <linux/module.h>
21 #include <linux/of_platform.h>
22 #include <linux/platform_data/pca953x.h>
23 #include <linux/regulator/consumer.h>
24 #include <linux/slab.h>
25 
26 #include <asm/unaligned.h>
27 
28 #define PCA953X_INPUT		0
29 #define PCA953X_OUTPUT		1
30 #define PCA953X_INVERT		2
31 #define PCA953X_DIRECTION	3
32 
33 #define REG_ADDR_AI		0x80
34 
35 #define PCA957X_IN		0
36 #define PCA957X_INVRT		1
37 #define PCA957X_BKEN		2
38 #define PCA957X_PUPD		3
39 #define PCA957X_CFG		4
40 #define PCA957X_OUT		5
41 #define PCA957X_MSK		6
42 #define PCA957X_INTS		7
43 
44 #define PCAL953X_IN_LATCH	34
45 #define PCAL953X_INT_MASK	37
46 #define PCAL953X_INT_STAT	38
47 
48 #define PCA_GPIO_MASK		0x00FF
49 #define PCA_INT			0x0100
50 #define PCA_PCAL		0x0200
51 #define PCA953X_TYPE		0x1000
52 #define PCA957X_TYPE		0x2000
53 #define PCA_TYPE_MASK		0xF000
54 
55 #define PCA_CHIP_TYPE(x)	((x) & PCA_TYPE_MASK)
56 
57 static const struct i2c_device_id pca953x_id[] = {
58 	{ "pca9505", 40 | PCA953X_TYPE | PCA_INT, },
59 	{ "pca9534", 8  | PCA953X_TYPE | PCA_INT, },
60 	{ "pca9535", 16 | PCA953X_TYPE | PCA_INT, },
61 	{ "pca9536", 4  | PCA953X_TYPE, },
62 	{ "pca9537", 4  | PCA953X_TYPE | PCA_INT, },
63 	{ "pca9538", 8  | PCA953X_TYPE | PCA_INT, },
64 	{ "pca9539", 16 | PCA953X_TYPE | PCA_INT, },
65 	{ "pca9554", 8  | PCA953X_TYPE | PCA_INT, },
66 	{ "pca9555", 16 | PCA953X_TYPE | PCA_INT, },
67 	{ "pca9556", 8  | PCA953X_TYPE, },
68 	{ "pca9557", 8  | PCA953X_TYPE, },
69 	{ "pca9574", 8  | PCA957X_TYPE | PCA_INT, },
70 	{ "pca9575", 16 | PCA957X_TYPE | PCA_INT, },
71 	{ "pca9698", 40 | PCA953X_TYPE, },
72 
73 	{ "pcal9555a", 16 | PCA953X_TYPE | PCA_INT | PCA_PCAL, },
74 
75 	{ "max7310", 8  | PCA953X_TYPE, },
76 	{ "max7312", 16 | PCA953X_TYPE | PCA_INT, },
77 	{ "max7313", 16 | PCA953X_TYPE | PCA_INT, },
78 	{ "max7315", 8  | PCA953X_TYPE | PCA_INT, },
79 	{ "max7318", 16 | PCA953X_TYPE | PCA_INT, },
80 	{ "pca6107", 8  | PCA953X_TYPE | PCA_INT, },
81 	{ "tca6408", 8  | PCA953X_TYPE | PCA_INT, },
82 	{ "tca6416", 16 | PCA953X_TYPE | PCA_INT, },
83 	{ "tca6424", 24 | PCA953X_TYPE | PCA_INT, },
84 	{ "tca9539", 16 | PCA953X_TYPE | PCA_INT, },
85 	{ "tca9554", 8  | PCA953X_TYPE | PCA_INT, },
86 	{ "xra1202", 8  | PCA953X_TYPE },
87 	{ }
88 };
89 MODULE_DEVICE_TABLE(i2c, pca953x_id);
90 
91 static const struct acpi_device_id pca953x_acpi_ids[] = {
92 	{ "INT3491", 16 | PCA953X_TYPE | PCA_INT | PCA_PCAL, },
93 	{ }
94 };
95 MODULE_DEVICE_TABLE(acpi, pca953x_acpi_ids);
96 
97 #define MAX_BANK 5
98 #define BANK_SZ 8
99 
100 #define NBANK(chip) DIV_ROUND_UP(chip->gpio_chip.ngpio, BANK_SZ)
101 
102 struct pca953x_reg_config {
103 	int direction;
104 	int output;
105 	int input;
106 };
107 
108 static const struct pca953x_reg_config pca953x_regs = {
109 	.direction = PCA953X_DIRECTION,
110 	.output = PCA953X_OUTPUT,
111 	.input = PCA953X_INPUT,
112 };
113 
114 static const struct pca953x_reg_config pca957x_regs = {
115 	.direction = PCA957X_CFG,
116 	.output = PCA957X_OUT,
117 	.input = PCA957X_IN,
118 };
119 
120 struct pca953x_chip {
121 	unsigned gpio_start;
122 	u8 reg_output[MAX_BANK];
123 	u8 reg_direction[MAX_BANK];
124 	struct mutex i2c_lock;
125 
126 #ifdef CONFIG_GPIO_PCA953X_IRQ
127 	struct mutex irq_lock;
128 	u8 irq_mask[MAX_BANK];
129 	u8 irq_stat[MAX_BANK];
130 	u8 irq_trig_raise[MAX_BANK];
131 	u8 irq_trig_fall[MAX_BANK];
132 #endif
133 
134 	struct i2c_client *client;
135 	struct gpio_chip gpio_chip;
136 	const char *const *names;
137 	unsigned long driver_data;
138 	struct regulator *regulator;
139 
140 	const struct pca953x_reg_config *regs;
141 
142 	int (*write_regs)(struct pca953x_chip *, int, u8 *);
143 	int (*read_regs)(struct pca953x_chip *, int, u8 *);
144 };
145 
146 static int pca953x_read_single(struct pca953x_chip *chip, int reg, u32 *val,
147 				int off)
148 {
149 	int ret;
150 	int bank_shift = fls((chip->gpio_chip.ngpio - 1) / BANK_SZ);
151 	int offset = off / BANK_SZ;
152 
153 	ret = i2c_smbus_read_byte_data(chip->client,
154 				(reg << bank_shift) + offset);
155 	*val = ret;
156 
157 	if (ret < 0) {
158 		dev_err(&chip->client->dev, "failed reading register\n");
159 		return ret;
160 	}
161 
162 	return 0;
163 }
164 
165 static int pca953x_write_single(struct pca953x_chip *chip, int reg, u32 val,
166 				int off)
167 {
168 	int ret;
169 	int bank_shift = fls((chip->gpio_chip.ngpio - 1) / BANK_SZ);
170 	int offset = off / BANK_SZ;
171 
172 	ret = i2c_smbus_write_byte_data(chip->client,
173 					(reg << bank_shift) + offset, val);
174 
175 	if (ret < 0) {
176 		dev_err(&chip->client->dev, "failed writing register\n");
177 		return ret;
178 	}
179 
180 	return 0;
181 }
182 
183 static int pca953x_write_regs_8(struct pca953x_chip *chip, int reg, u8 *val)
184 {
185 	return i2c_smbus_write_byte_data(chip->client, reg, *val);
186 }
187 
188 static int pca953x_write_regs_16(struct pca953x_chip *chip, int reg, u8 *val)
189 {
190 	u16 word = get_unaligned((u16 *)val);
191 
192 	return i2c_smbus_write_word_data(chip->client, reg << 1, word);
193 }
194 
195 static int pca957x_write_regs_16(struct pca953x_chip *chip, int reg, u8 *val)
196 {
197 	int ret;
198 
199 	ret = i2c_smbus_write_byte_data(chip->client, reg << 1, val[0]);
200 	if (ret < 0)
201 		return ret;
202 
203 	return i2c_smbus_write_byte_data(chip->client, (reg << 1) + 1, val[1]);
204 }
205 
206 static int pca953x_write_regs_24(struct pca953x_chip *chip, int reg, u8 *val)
207 {
208 	int bank_shift = fls((chip->gpio_chip.ngpio - 1) / BANK_SZ);
209 
210 	return i2c_smbus_write_i2c_block_data(chip->client,
211 					      (reg << bank_shift) | REG_ADDR_AI,
212 					      NBANK(chip), val);
213 }
214 
215 static int pca953x_write_regs(struct pca953x_chip *chip, int reg, u8 *val)
216 {
217 	int ret = 0;
218 
219 	ret = chip->write_regs(chip, reg, val);
220 	if (ret < 0) {
221 		dev_err(&chip->client->dev, "failed writing register\n");
222 		return ret;
223 	}
224 
225 	return 0;
226 }
227 
228 static int pca953x_read_regs_8(struct pca953x_chip *chip, int reg, u8 *val)
229 {
230 	int ret;
231 
232 	ret = i2c_smbus_read_byte_data(chip->client, reg);
233 	*val = ret;
234 
235 	return ret;
236 }
237 
238 static int pca953x_read_regs_16(struct pca953x_chip *chip, int reg, u8 *val)
239 {
240 	int ret;
241 
242 	ret = i2c_smbus_read_word_data(chip->client, reg << 1);
243 	put_unaligned(ret, (u16 *)val);
244 
245 	return ret;
246 }
247 
248 static int pca953x_read_regs_24(struct pca953x_chip *chip, int reg, u8 *val)
249 {
250 	int bank_shift = fls((chip->gpio_chip.ngpio - 1) / BANK_SZ);
251 
252 	return i2c_smbus_read_i2c_block_data(chip->client,
253 					     (reg << bank_shift) | REG_ADDR_AI,
254 					     NBANK(chip), val);
255 }
256 
257 static int pca953x_read_regs(struct pca953x_chip *chip, int reg, u8 *val)
258 {
259 	int ret;
260 
261 	ret = chip->read_regs(chip, reg, val);
262 	if (ret < 0) {
263 		dev_err(&chip->client->dev, "failed reading register\n");
264 		return ret;
265 	}
266 
267 	return 0;
268 }
269 
270 static int pca953x_gpio_direction_input(struct gpio_chip *gc, unsigned off)
271 {
272 	struct pca953x_chip *chip = gpiochip_get_data(gc);
273 	u8 reg_val;
274 	int ret;
275 
276 	mutex_lock(&chip->i2c_lock);
277 	reg_val = chip->reg_direction[off / BANK_SZ] | (1u << (off % BANK_SZ));
278 
279 	ret = pca953x_write_single(chip, chip->regs->direction, reg_val, off);
280 	if (ret)
281 		goto exit;
282 
283 	chip->reg_direction[off / BANK_SZ] = reg_val;
284 exit:
285 	mutex_unlock(&chip->i2c_lock);
286 	return ret;
287 }
288 
289 static int pca953x_gpio_direction_output(struct gpio_chip *gc,
290 		unsigned off, int val)
291 {
292 	struct pca953x_chip *chip = gpiochip_get_data(gc);
293 	u8 reg_val;
294 	int ret;
295 
296 	mutex_lock(&chip->i2c_lock);
297 	/* set output level */
298 	if (val)
299 		reg_val = chip->reg_output[off / BANK_SZ]
300 			| (1u << (off % BANK_SZ));
301 	else
302 		reg_val = chip->reg_output[off / BANK_SZ]
303 			& ~(1u << (off % BANK_SZ));
304 
305 	ret = pca953x_write_single(chip, chip->regs->output, reg_val, off);
306 	if (ret)
307 		goto exit;
308 
309 	chip->reg_output[off / BANK_SZ] = reg_val;
310 
311 	/* then direction */
312 	reg_val = chip->reg_direction[off / BANK_SZ] & ~(1u << (off % BANK_SZ));
313 	ret = pca953x_write_single(chip, chip->regs->direction, reg_val, off);
314 	if (ret)
315 		goto exit;
316 
317 	chip->reg_direction[off / BANK_SZ] = reg_val;
318 exit:
319 	mutex_unlock(&chip->i2c_lock);
320 	return ret;
321 }
322 
323 static int pca953x_gpio_get_value(struct gpio_chip *gc, unsigned off)
324 {
325 	struct pca953x_chip *chip = gpiochip_get_data(gc);
326 	u32 reg_val;
327 	int ret;
328 
329 	mutex_lock(&chip->i2c_lock);
330 	ret = pca953x_read_single(chip, chip->regs->input, &reg_val, off);
331 	mutex_unlock(&chip->i2c_lock);
332 	if (ret < 0) {
333 		/* NOTE:  diagnostic already emitted; that's all we should
334 		 * do unless gpio_*_value_cansleep() calls become different
335 		 * from their nonsleeping siblings (and report faults).
336 		 */
337 		return 0;
338 	}
339 
340 	return (reg_val & (1u << (off % BANK_SZ))) ? 1 : 0;
341 }
342 
343 static void pca953x_gpio_set_value(struct gpio_chip *gc, unsigned off, int val)
344 {
345 	struct pca953x_chip *chip = gpiochip_get_data(gc);
346 	u8 reg_val;
347 	int ret;
348 
349 	mutex_lock(&chip->i2c_lock);
350 	if (val)
351 		reg_val = chip->reg_output[off / BANK_SZ]
352 			| (1u << (off % BANK_SZ));
353 	else
354 		reg_val = chip->reg_output[off / BANK_SZ]
355 			& ~(1u << (off % BANK_SZ));
356 
357 	ret = pca953x_write_single(chip, chip->regs->output, reg_val, off);
358 	if (ret)
359 		goto exit;
360 
361 	chip->reg_output[off / BANK_SZ] = reg_val;
362 exit:
363 	mutex_unlock(&chip->i2c_lock);
364 }
365 
366 static int pca953x_gpio_get_direction(struct gpio_chip *gc, unsigned off)
367 {
368 	struct pca953x_chip *chip = gpiochip_get_data(gc);
369 	u32 reg_val;
370 	int ret;
371 
372 	mutex_lock(&chip->i2c_lock);
373 	ret = pca953x_read_single(chip, chip->regs->direction, &reg_val, off);
374 	mutex_unlock(&chip->i2c_lock);
375 	if (ret < 0)
376 		return ret;
377 
378 	return !!(reg_val & (1u << (off % BANK_SZ)));
379 }
380 
381 static void pca953x_gpio_set_multiple(struct gpio_chip *gc,
382 				      unsigned long *mask, unsigned long *bits)
383 {
384 	struct pca953x_chip *chip = gpiochip_get_data(gc);
385 	unsigned int bank_mask, bank_val;
386 	int bank_shift, bank;
387 	u8 reg_val[MAX_BANK];
388 	int ret;
389 
390 	bank_shift = fls((chip->gpio_chip.ngpio - 1) / BANK_SZ);
391 
392 	mutex_lock(&chip->i2c_lock);
393 	memcpy(reg_val, chip->reg_output, NBANK(chip));
394 	for (bank = 0; bank < NBANK(chip); bank++) {
395 		bank_mask = mask[bank / sizeof(*mask)] >>
396 			   ((bank % sizeof(*mask)) * 8);
397 		if (bank_mask) {
398 			bank_val = bits[bank / sizeof(*bits)] >>
399 				  ((bank % sizeof(*bits)) * 8);
400 			bank_val &= bank_mask;
401 			reg_val[bank] = (reg_val[bank] & ~bank_mask) | bank_val;
402 		}
403 	}
404 
405 	ret = i2c_smbus_write_i2c_block_data(chip->client,
406 					     chip->regs->output << bank_shift,
407 					     NBANK(chip), reg_val);
408 	if (ret)
409 		goto exit;
410 
411 	memcpy(chip->reg_output, reg_val, NBANK(chip));
412 exit:
413 	mutex_unlock(&chip->i2c_lock);
414 }
415 
416 static void pca953x_setup_gpio(struct pca953x_chip *chip, int gpios)
417 {
418 	struct gpio_chip *gc;
419 
420 	gc = &chip->gpio_chip;
421 
422 	gc->direction_input  = pca953x_gpio_direction_input;
423 	gc->direction_output = pca953x_gpio_direction_output;
424 	gc->get = pca953x_gpio_get_value;
425 	gc->set = pca953x_gpio_set_value;
426 	gc->get_direction = pca953x_gpio_get_direction;
427 	gc->set_multiple = pca953x_gpio_set_multiple;
428 	gc->can_sleep = true;
429 
430 	gc->base = chip->gpio_start;
431 	gc->ngpio = gpios;
432 	gc->label = chip->client->name;
433 	gc->parent = &chip->client->dev;
434 	gc->owner = THIS_MODULE;
435 	gc->names = chip->names;
436 }
437 
438 #ifdef CONFIG_GPIO_PCA953X_IRQ
439 static void pca953x_irq_mask(struct irq_data *d)
440 {
441 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
442 	struct pca953x_chip *chip = gpiochip_get_data(gc);
443 
444 	chip->irq_mask[d->hwirq / BANK_SZ] &= ~(1 << (d->hwirq % BANK_SZ));
445 }
446 
447 static void pca953x_irq_unmask(struct irq_data *d)
448 {
449 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
450 	struct pca953x_chip *chip = gpiochip_get_data(gc);
451 
452 	chip->irq_mask[d->hwirq / BANK_SZ] |= 1 << (d->hwirq % BANK_SZ);
453 }
454 
455 static void pca953x_irq_bus_lock(struct irq_data *d)
456 {
457 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
458 	struct pca953x_chip *chip = gpiochip_get_data(gc);
459 
460 	mutex_lock(&chip->irq_lock);
461 }
462 
463 static void pca953x_irq_bus_sync_unlock(struct irq_data *d)
464 {
465 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
466 	struct pca953x_chip *chip = gpiochip_get_data(gc);
467 	u8 new_irqs;
468 	int level, i;
469 	u8 invert_irq_mask[MAX_BANK];
470 
471 	if (chip->driver_data & PCA_PCAL) {
472 		/* Enable latch on interrupt-enabled inputs */
473 		pca953x_write_regs(chip, PCAL953X_IN_LATCH, chip->irq_mask);
474 
475 		for (i = 0; i < NBANK(chip); i++)
476 			invert_irq_mask[i] = ~chip->irq_mask[i];
477 
478 		/* Unmask enabled interrupts */
479 		pca953x_write_regs(chip, PCAL953X_INT_MASK, invert_irq_mask);
480 	}
481 
482 	/* Look for any newly setup interrupt */
483 	for (i = 0; i < NBANK(chip); i++) {
484 		new_irqs = chip->irq_trig_fall[i] | chip->irq_trig_raise[i];
485 		new_irqs &= ~chip->reg_direction[i];
486 
487 		while (new_irqs) {
488 			level = __ffs(new_irqs);
489 			pca953x_gpio_direction_input(&chip->gpio_chip,
490 							level + (BANK_SZ * i));
491 			new_irqs &= ~(1 << level);
492 		}
493 	}
494 
495 	mutex_unlock(&chip->irq_lock);
496 }
497 
498 static int pca953x_irq_set_type(struct irq_data *d, unsigned int type)
499 {
500 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
501 	struct pca953x_chip *chip = gpiochip_get_data(gc);
502 	int bank_nb = d->hwirq / BANK_SZ;
503 	u8 mask = 1 << (d->hwirq % BANK_SZ);
504 
505 	if (!(type & IRQ_TYPE_EDGE_BOTH)) {
506 		dev_err(&chip->client->dev, "irq %d: unsupported type %d\n",
507 			d->irq, type);
508 		return -EINVAL;
509 	}
510 
511 	if (type & IRQ_TYPE_EDGE_FALLING)
512 		chip->irq_trig_fall[bank_nb] |= mask;
513 	else
514 		chip->irq_trig_fall[bank_nb] &= ~mask;
515 
516 	if (type & IRQ_TYPE_EDGE_RISING)
517 		chip->irq_trig_raise[bank_nb] |= mask;
518 	else
519 		chip->irq_trig_raise[bank_nb] &= ~mask;
520 
521 	return 0;
522 }
523 
524 static struct irq_chip pca953x_irq_chip = {
525 	.name			= "pca953x",
526 	.irq_mask		= pca953x_irq_mask,
527 	.irq_unmask		= pca953x_irq_unmask,
528 	.irq_bus_lock		= pca953x_irq_bus_lock,
529 	.irq_bus_sync_unlock	= pca953x_irq_bus_sync_unlock,
530 	.irq_set_type		= pca953x_irq_set_type,
531 };
532 
533 static bool pca953x_irq_pending(struct pca953x_chip *chip, u8 *pending)
534 {
535 	u8 cur_stat[MAX_BANK];
536 	u8 old_stat[MAX_BANK];
537 	bool pending_seen = false;
538 	bool trigger_seen = false;
539 	u8 trigger[MAX_BANK];
540 	int ret, i;
541 
542 	if (chip->driver_data & PCA_PCAL) {
543 		/* Read the current interrupt status from the device */
544 		ret = pca953x_read_regs(chip, PCAL953X_INT_STAT, trigger);
545 		if (ret)
546 			return false;
547 
548 		/* Check latched inputs and clear interrupt status */
549 		ret = pca953x_read_regs(chip, PCA953X_INPUT, cur_stat);
550 		if (ret)
551 			return false;
552 
553 		for (i = 0; i < NBANK(chip); i++) {
554 			/* Apply filter for rising/falling edge selection */
555 			pending[i] = (~cur_stat[i] & chip->irq_trig_fall[i]) |
556 				(cur_stat[i] & chip->irq_trig_raise[i]);
557 			pending[i] &= trigger[i];
558 			if (pending[i])
559 				pending_seen = true;
560 		}
561 
562 		return pending_seen;
563 	}
564 
565 	ret = pca953x_read_regs(chip, chip->regs->input, cur_stat);
566 	if (ret)
567 		return false;
568 
569 	/* Remove output pins from the equation */
570 	for (i = 0; i < NBANK(chip); i++)
571 		cur_stat[i] &= chip->reg_direction[i];
572 
573 	memcpy(old_stat, chip->irq_stat, NBANK(chip));
574 
575 	for (i = 0; i < NBANK(chip); i++) {
576 		trigger[i] = (cur_stat[i] ^ old_stat[i]) & chip->irq_mask[i];
577 		if (trigger[i])
578 			trigger_seen = true;
579 	}
580 
581 	if (!trigger_seen)
582 		return false;
583 
584 	memcpy(chip->irq_stat, cur_stat, NBANK(chip));
585 
586 	for (i = 0; i < NBANK(chip); i++) {
587 		pending[i] = (old_stat[i] & chip->irq_trig_fall[i]) |
588 			(cur_stat[i] & chip->irq_trig_raise[i]);
589 		pending[i] &= trigger[i];
590 		if (pending[i])
591 			pending_seen = true;
592 	}
593 
594 	return pending_seen;
595 }
596 
597 static irqreturn_t pca953x_irq_handler(int irq, void *devid)
598 {
599 	struct pca953x_chip *chip = devid;
600 	u8 pending[MAX_BANK];
601 	u8 level;
602 	unsigned nhandled = 0;
603 	int i;
604 
605 	if (!pca953x_irq_pending(chip, pending))
606 		return IRQ_NONE;
607 
608 	for (i = 0; i < NBANK(chip); i++) {
609 		while (pending[i]) {
610 			level = __ffs(pending[i]);
611 			handle_nested_irq(irq_find_mapping(chip->gpio_chip.irq.domain,
612 							level + (BANK_SZ * i)));
613 			pending[i] &= ~(1 << level);
614 			nhandled++;
615 		}
616 	}
617 
618 	return (nhandled > 0) ? IRQ_HANDLED : IRQ_NONE;
619 }
620 
621 static int pca953x_irq_setup(struct pca953x_chip *chip,
622 			     int irq_base)
623 {
624 	struct i2c_client *client = chip->client;
625 	int ret, i;
626 
627 	if (client->irq && irq_base != -1
628 			&& (chip->driver_data & PCA_INT)) {
629 		ret = pca953x_read_regs(chip,
630 					chip->regs->input, chip->irq_stat);
631 		if (ret)
632 			return ret;
633 
634 		/*
635 		 * There is no way to know which GPIO line generated the
636 		 * interrupt.  We have to rely on the previous read for
637 		 * this purpose.
638 		 */
639 		for (i = 0; i < NBANK(chip); i++)
640 			chip->irq_stat[i] &= chip->reg_direction[i];
641 		mutex_init(&chip->irq_lock);
642 
643 		ret = devm_request_threaded_irq(&client->dev,
644 					client->irq,
645 					   NULL,
646 					   pca953x_irq_handler,
647 					   IRQF_TRIGGER_LOW | IRQF_ONESHOT |
648 						   IRQF_SHARED,
649 					   dev_name(&client->dev), chip);
650 		if (ret) {
651 			dev_err(&client->dev, "failed to request irq %d\n",
652 				client->irq);
653 			return ret;
654 		}
655 
656 		ret =  gpiochip_irqchip_add_nested(&chip->gpio_chip,
657 						   &pca953x_irq_chip,
658 						   irq_base,
659 						   handle_simple_irq,
660 						   IRQ_TYPE_NONE);
661 		if (ret) {
662 			dev_err(&client->dev,
663 				"could not connect irqchip to gpiochip\n");
664 			return ret;
665 		}
666 
667 		gpiochip_set_nested_irqchip(&chip->gpio_chip,
668 					    &pca953x_irq_chip,
669 					    client->irq);
670 	}
671 
672 	return 0;
673 }
674 
675 #else /* CONFIG_GPIO_PCA953X_IRQ */
676 static int pca953x_irq_setup(struct pca953x_chip *chip,
677 			     int irq_base)
678 {
679 	struct i2c_client *client = chip->client;
680 
681 	if (irq_base != -1 && (chip->driver_data & PCA_INT))
682 		dev_warn(&client->dev, "interrupt support not compiled in\n");
683 
684 	return 0;
685 }
686 #endif
687 
688 static int device_pca953x_init(struct pca953x_chip *chip, u32 invert)
689 {
690 	int ret;
691 	u8 val[MAX_BANK];
692 
693 	chip->regs = &pca953x_regs;
694 
695 	ret = pca953x_read_regs(chip, chip->regs->output, chip->reg_output);
696 	if (ret)
697 		goto out;
698 
699 	ret = pca953x_read_regs(chip, chip->regs->direction,
700 				chip->reg_direction);
701 	if (ret)
702 		goto out;
703 
704 	/* set platform specific polarity inversion */
705 	if (invert)
706 		memset(val, 0xFF, NBANK(chip));
707 	else
708 		memset(val, 0, NBANK(chip));
709 
710 	ret = pca953x_write_regs(chip, PCA953X_INVERT, val);
711 out:
712 	return ret;
713 }
714 
715 static int device_pca957x_init(struct pca953x_chip *chip, u32 invert)
716 {
717 	int ret;
718 	u8 val[MAX_BANK];
719 
720 	chip->regs = &pca957x_regs;
721 
722 	ret = pca953x_read_regs(chip, chip->regs->output, chip->reg_output);
723 	if (ret)
724 		goto out;
725 	ret = pca953x_read_regs(chip, chip->regs->direction,
726 				chip->reg_direction);
727 	if (ret)
728 		goto out;
729 
730 	/* set platform specific polarity inversion */
731 	if (invert)
732 		memset(val, 0xFF, NBANK(chip));
733 	else
734 		memset(val, 0, NBANK(chip));
735 	ret = pca953x_write_regs(chip, PCA957X_INVRT, val);
736 	if (ret)
737 		goto out;
738 
739 	/* To enable register 6, 7 to control pull up and pull down */
740 	memset(val, 0x02, NBANK(chip));
741 	ret = pca953x_write_regs(chip, PCA957X_BKEN, val);
742 	if (ret)
743 		goto out;
744 
745 	return 0;
746 out:
747 	return ret;
748 }
749 
750 static const struct of_device_id pca953x_dt_ids[];
751 
752 static int pca953x_probe(struct i2c_client *client,
753 				   const struct i2c_device_id *i2c_id)
754 {
755 	struct pca953x_platform_data *pdata;
756 	struct pca953x_chip *chip;
757 	int irq_base = 0;
758 	int ret;
759 	u32 invert = 0;
760 	struct regulator *reg;
761 
762 	chip = devm_kzalloc(&client->dev,
763 			sizeof(struct pca953x_chip), GFP_KERNEL);
764 	if (chip == NULL)
765 		return -ENOMEM;
766 
767 	pdata = dev_get_platdata(&client->dev);
768 	if (pdata) {
769 		irq_base = pdata->irq_base;
770 		chip->gpio_start = pdata->gpio_base;
771 		invert = pdata->invert;
772 		chip->names = pdata->names;
773 	} else {
774 		struct gpio_desc *reset_gpio;
775 
776 		chip->gpio_start = -1;
777 		irq_base = 0;
778 
779 		/*
780 		 * See if we need to de-assert a reset pin.
781 		 *
782 		 * There is no known ACPI-enabled platforms that are
783 		 * using "reset" GPIO. Otherwise any of those platform
784 		 * must use _DSD method with corresponding property.
785 		 */
786 		reset_gpio = devm_gpiod_get_optional(&client->dev, "reset",
787 						     GPIOD_OUT_LOW);
788 		if (IS_ERR(reset_gpio))
789 			return PTR_ERR(reset_gpio);
790 	}
791 
792 	chip->client = client;
793 
794 	reg = devm_regulator_get(&client->dev, "vcc");
795 	if (IS_ERR(reg)) {
796 		ret = PTR_ERR(reg);
797 		if (ret != -EPROBE_DEFER)
798 			dev_err(&client->dev, "reg get err: %d\n", ret);
799 		return ret;
800 	}
801 	ret = regulator_enable(reg);
802 	if (ret) {
803 		dev_err(&client->dev, "reg en err: %d\n", ret);
804 		return ret;
805 	}
806 	chip->regulator = reg;
807 
808 	if (i2c_id) {
809 		chip->driver_data = i2c_id->driver_data;
810 	} else {
811 		const struct acpi_device_id *acpi_id;
812 		const struct of_device_id *match;
813 
814 		match = of_match_device(pca953x_dt_ids, &client->dev);
815 		if (match) {
816 			chip->driver_data = (int)(uintptr_t)match->data;
817 		} else {
818 			acpi_id = acpi_match_device(pca953x_acpi_ids, &client->dev);
819 			if (!acpi_id) {
820 				ret = -ENODEV;
821 				goto err_exit;
822 			}
823 
824 			chip->driver_data = acpi_id->driver_data;
825 		}
826 	}
827 
828 	mutex_init(&chip->i2c_lock);
829 	/*
830 	 * In case we have an i2c-mux controlled by a GPIO provided by an
831 	 * expander using the same driver higher on the device tree, read the
832 	 * i2c adapter nesting depth and use the retrieved value as lockdep
833 	 * subclass for chip->i2c_lock.
834 	 *
835 	 * REVISIT: This solution is not complete. It protects us from lockdep
836 	 * false positives when the expander controlling the i2c-mux is on
837 	 * a different level on the device tree, but not when it's on the same
838 	 * level on a different branch (in which case the subclass number
839 	 * would be the same).
840 	 *
841 	 * TODO: Once a correct solution is developed, a similar fix should be
842 	 * applied to all other i2c-controlled GPIO expanders (and potentially
843 	 * regmap-i2c).
844 	 */
845 	lockdep_set_subclass(&chip->i2c_lock,
846 			     i2c_adapter_depth(client->adapter));
847 
848 	/* initialize cached registers from their original values.
849 	 * we can't share this chip with another i2c master.
850 	 */
851 	pca953x_setup_gpio(chip, chip->driver_data & PCA_GPIO_MASK);
852 
853 	if (chip->gpio_chip.ngpio <= 8) {
854 		chip->write_regs = pca953x_write_regs_8;
855 		chip->read_regs = pca953x_read_regs_8;
856 	} else if (chip->gpio_chip.ngpio >= 24) {
857 		chip->write_regs = pca953x_write_regs_24;
858 		chip->read_regs = pca953x_read_regs_24;
859 	} else {
860 		if (PCA_CHIP_TYPE(chip->driver_data) == PCA953X_TYPE)
861 			chip->write_regs = pca953x_write_regs_16;
862 		else
863 			chip->write_regs = pca957x_write_regs_16;
864 		chip->read_regs = pca953x_read_regs_16;
865 	}
866 
867 	if (PCA_CHIP_TYPE(chip->driver_data) == PCA953X_TYPE)
868 		ret = device_pca953x_init(chip, invert);
869 	else
870 		ret = device_pca957x_init(chip, invert);
871 	if (ret)
872 		goto err_exit;
873 
874 	ret = devm_gpiochip_add_data(&client->dev, &chip->gpio_chip, chip);
875 	if (ret)
876 		goto err_exit;
877 
878 	ret = pca953x_irq_setup(chip, irq_base);
879 	if (ret)
880 		goto err_exit;
881 
882 	if (pdata && pdata->setup) {
883 		ret = pdata->setup(client, chip->gpio_chip.base,
884 				chip->gpio_chip.ngpio, pdata->context);
885 		if (ret < 0)
886 			dev_warn(&client->dev, "setup failed, %d\n", ret);
887 	}
888 
889 	i2c_set_clientdata(client, chip);
890 	return 0;
891 
892 err_exit:
893 	regulator_disable(chip->regulator);
894 	return ret;
895 }
896 
897 static int pca953x_remove(struct i2c_client *client)
898 {
899 	struct pca953x_platform_data *pdata = dev_get_platdata(&client->dev);
900 	struct pca953x_chip *chip = i2c_get_clientdata(client);
901 	int ret;
902 
903 	if (pdata && pdata->teardown) {
904 		ret = pdata->teardown(client, chip->gpio_chip.base,
905 				chip->gpio_chip.ngpio, pdata->context);
906 		if (ret < 0)
907 			dev_err(&client->dev, "%s failed, %d\n",
908 					"teardown", ret);
909 	} else {
910 		ret = 0;
911 	}
912 
913 	regulator_disable(chip->regulator);
914 
915 	return ret;
916 }
917 
918 /* convenience to stop overlong match-table lines */
919 #define OF_953X(__nrgpio, __int) (void *)(__nrgpio | PCA953X_TYPE | __int)
920 #define OF_957X(__nrgpio, __int) (void *)(__nrgpio | PCA957X_TYPE | __int)
921 
922 static const struct of_device_id pca953x_dt_ids[] = {
923 	{ .compatible = "nxp,pca9505", .data = OF_953X(40, PCA_INT), },
924 	{ .compatible = "nxp,pca9534", .data = OF_953X( 8, PCA_INT), },
925 	{ .compatible = "nxp,pca9535", .data = OF_953X(16, PCA_INT), },
926 	{ .compatible = "nxp,pca9536", .data = OF_953X( 4, 0), },
927 	{ .compatible = "nxp,pca9537", .data = OF_953X( 4, PCA_INT), },
928 	{ .compatible = "nxp,pca9538", .data = OF_953X( 8, PCA_INT), },
929 	{ .compatible = "nxp,pca9539", .data = OF_953X(16, PCA_INT), },
930 	{ .compatible = "nxp,pca9554", .data = OF_953X( 8, PCA_INT), },
931 	{ .compatible = "nxp,pca9555", .data = OF_953X(16, PCA_INT), },
932 	{ .compatible = "nxp,pca9556", .data = OF_953X( 8, 0), },
933 	{ .compatible = "nxp,pca9557", .data = OF_953X( 8, 0), },
934 	{ .compatible = "nxp,pca9574", .data = OF_957X( 8, PCA_INT), },
935 	{ .compatible = "nxp,pca9575", .data = OF_957X(16, PCA_INT), },
936 	{ .compatible = "nxp,pca9698", .data = OF_953X(40, 0), },
937 
938 	{ .compatible = "maxim,max7310", .data = OF_953X( 8, 0), },
939 	{ .compatible = "maxim,max7312", .data = OF_953X(16, PCA_INT), },
940 	{ .compatible = "maxim,max7313", .data = OF_953X(16, PCA_INT), },
941 	{ .compatible = "maxim,max7315", .data = OF_953X( 8, PCA_INT), },
942 	{ .compatible = "maxim,max7318", .data = OF_953X(16, PCA_INT), },
943 
944 	{ .compatible = "ti,pca6107", .data = OF_953X( 8, PCA_INT), },
945 	{ .compatible = "ti,pca9536", .data = OF_953X( 4, 0), },
946 	{ .compatible = "ti,tca6408", .data = OF_953X( 8, PCA_INT), },
947 	{ .compatible = "ti,tca6416", .data = OF_953X(16, PCA_INT), },
948 	{ .compatible = "ti,tca6424", .data = OF_953X(24, PCA_INT), },
949 
950 	{ .compatible = "onnn,pca9654", .data = OF_953X( 8, PCA_INT), },
951 
952 	{ .compatible = "exar,xra1202", .data = OF_953X( 8, 0), },
953 	{ }
954 };
955 
956 MODULE_DEVICE_TABLE(of, pca953x_dt_ids);
957 
958 static struct i2c_driver pca953x_driver = {
959 	.driver = {
960 		.name	= "pca953x",
961 		.of_match_table = pca953x_dt_ids,
962 		.acpi_match_table = ACPI_PTR(pca953x_acpi_ids),
963 	},
964 	.probe		= pca953x_probe,
965 	.remove		= pca953x_remove,
966 	.id_table	= pca953x_id,
967 };
968 
969 static int __init pca953x_init(void)
970 {
971 	return i2c_add_driver(&pca953x_driver);
972 }
973 /* register after i2c postcore initcall and before
974  * subsys initcalls that may rely on these GPIOs
975  */
976 subsys_initcall(pca953x_init);
977 
978 static void __exit pca953x_exit(void)
979 {
980 	i2c_del_driver(&pca953x_driver);
981 }
982 module_exit(pca953x_exit);
983 
984 MODULE_AUTHOR("eric miao <eric.miao@marvell.com>");
985 MODULE_DESCRIPTION("GPIO expander driver for PCA953x");
986 MODULE_LICENSE("GPL");
987