xref: /openbmc/linux/drivers/gpio/gpio-pca953x.c (revision 2359ccdd)
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 	{ "pcal6524", 24 | PCA953X_TYPE | PCA_INT | PCA_PCAL, },
74 	{ "pcal9555a", 16 | PCA953X_TYPE | PCA_INT | PCA_PCAL, },
75 
76 	{ "max7310", 8  | PCA953X_TYPE, },
77 	{ "max7312", 16 | PCA953X_TYPE | PCA_INT, },
78 	{ "max7313", 16 | PCA953X_TYPE | PCA_INT, },
79 	{ "max7315", 8  | PCA953X_TYPE | PCA_INT, },
80 	{ "max7318", 16 | PCA953X_TYPE | PCA_INT, },
81 	{ "pca6107", 8  | PCA953X_TYPE | PCA_INT, },
82 	{ "tca6408", 8  | PCA953X_TYPE | PCA_INT, },
83 	{ "tca6416", 16 | PCA953X_TYPE | PCA_INT, },
84 	{ "tca6424", 24 | PCA953X_TYPE | PCA_INT, },
85 	{ "tca9539", 16 | PCA953X_TYPE | PCA_INT, },
86 	{ "tca9554", 8  | PCA953X_TYPE | PCA_INT, },
87 	{ "xra1202", 8  | PCA953X_TYPE },
88 	{ }
89 };
90 MODULE_DEVICE_TABLE(i2c, pca953x_id);
91 
92 static const struct acpi_device_id pca953x_acpi_ids[] = {
93 	{ "INT3491", 16 | PCA953X_TYPE | PCA_INT | PCA_PCAL, },
94 	{ }
95 };
96 MODULE_DEVICE_TABLE(acpi, pca953x_acpi_ids);
97 
98 #define MAX_BANK 5
99 #define BANK_SZ 8
100 
101 #define NBANK(chip) DIV_ROUND_UP(chip->gpio_chip.ngpio, BANK_SZ)
102 
103 struct pca953x_reg_config {
104 	int direction;
105 	int output;
106 	int input;
107 };
108 
109 static const struct pca953x_reg_config pca953x_regs = {
110 	.direction = PCA953X_DIRECTION,
111 	.output = PCA953X_OUTPUT,
112 	.input = PCA953X_INPUT,
113 };
114 
115 static const struct pca953x_reg_config pca957x_regs = {
116 	.direction = PCA957X_CFG,
117 	.output = PCA957X_OUT,
118 	.input = PCA957X_IN,
119 };
120 
121 struct pca953x_chip {
122 	unsigned gpio_start;
123 	u8 reg_output[MAX_BANK];
124 	u8 reg_direction[MAX_BANK];
125 	struct mutex i2c_lock;
126 
127 #ifdef CONFIG_GPIO_PCA953X_IRQ
128 	struct mutex irq_lock;
129 	u8 irq_mask[MAX_BANK];
130 	u8 irq_stat[MAX_BANK];
131 	u8 irq_trig_raise[MAX_BANK];
132 	u8 irq_trig_fall[MAX_BANK];
133 #endif
134 
135 	struct i2c_client *client;
136 	struct gpio_chip gpio_chip;
137 	const char *const *names;
138 	unsigned long driver_data;
139 	struct regulator *regulator;
140 
141 	const struct pca953x_reg_config *regs;
142 
143 	int (*write_regs)(struct pca953x_chip *, int, u8 *);
144 	int (*read_regs)(struct pca953x_chip *, int, u8 *);
145 };
146 
147 static int pca953x_read_single(struct pca953x_chip *chip, int reg, u32 *val,
148 				int off)
149 {
150 	int ret;
151 	int bank_shift = fls((chip->gpio_chip.ngpio - 1) / BANK_SZ);
152 	int offset = off / BANK_SZ;
153 
154 	ret = i2c_smbus_read_byte_data(chip->client,
155 				(reg << bank_shift) + offset);
156 	*val = ret;
157 
158 	if (ret < 0) {
159 		dev_err(&chip->client->dev, "failed reading register\n");
160 		return ret;
161 	}
162 
163 	return 0;
164 }
165 
166 static int pca953x_write_single(struct pca953x_chip *chip, int reg, u32 val,
167 				int off)
168 {
169 	int ret;
170 	int bank_shift = fls((chip->gpio_chip.ngpio - 1) / BANK_SZ);
171 	int offset = off / BANK_SZ;
172 
173 	ret = i2c_smbus_write_byte_data(chip->client,
174 					(reg << bank_shift) + offset, val);
175 
176 	if (ret < 0) {
177 		dev_err(&chip->client->dev, "failed writing register\n");
178 		return ret;
179 	}
180 
181 	return 0;
182 }
183 
184 static int pca953x_write_regs_8(struct pca953x_chip *chip, int reg, u8 *val)
185 {
186 	return i2c_smbus_write_byte_data(chip->client, reg, *val);
187 }
188 
189 static int pca953x_write_regs_16(struct pca953x_chip *chip, int reg, u8 *val)
190 {
191 	u16 word = get_unaligned((u16 *)val);
192 
193 	return i2c_smbus_write_word_data(chip->client, reg << 1, word);
194 }
195 
196 static int pca957x_write_regs_16(struct pca953x_chip *chip, int reg, u8 *val)
197 {
198 	int ret;
199 
200 	ret = i2c_smbus_write_byte_data(chip->client, reg << 1, val[0]);
201 	if (ret < 0)
202 		return ret;
203 
204 	return i2c_smbus_write_byte_data(chip->client, (reg << 1) + 1, val[1]);
205 }
206 
207 static int pca953x_write_regs_24(struct pca953x_chip *chip, int reg, u8 *val)
208 {
209 	int bank_shift = fls((chip->gpio_chip.ngpio - 1) / BANK_SZ);
210 
211 	return i2c_smbus_write_i2c_block_data(chip->client,
212 					      (reg << bank_shift) | REG_ADDR_AI,
213 					      NBANK(chip), val);
214 }
215 
216 static int pca953x_write_regs(struct pca953x_chip *chip, int reg, u8 *val)
217 {
218 	int ret = 0;
219 
220 	ret = chip->write_regs(chip, reg, val);
221 	if (ret < 0) {
222 		dev_err(&chip->client->dev, "failed writing register\n");
223 		return ret;
224 	}
225 
226 	return 0;
227 }
228 
229 static int pca953x_read_regs_8(struct pca953x_chip *chip, int reg, u8 *val)
230 {
231 	int ret;
232 
233 	ret = i2c_smbus_read_byte_data(chip->client, reg);
234 	*val = ret;
235 
236 	return ret;
237 }
238 
239 static int pca953x_read_regs_16(struct pca953x_chip *chip, int reg, u8 *val)
240 {
241 	int ret;
242 
243 	ret = i2c_smbus_read_word_data(chip->client, reg << 1);
244 	put_unaligned(ret, (u16 *)val);
245 
246 	return ret;
247 }
248 
249 static int pca953x_read_regs_24(struct pca953x_chip *chip, int reg, u8 *val)
250 {
251 	int bank_shift = fls((chip->gpio_chip.ngpio - 1) / BANK_SZ);
252 
253 	return i2c_smbus_read_i2c_block_data(chip->client,
254 					     (reg << bank_shift) | REG_ADDR_AI,
255 					     NBANK(chip), val);
256 }
257 
258 static int pca953x_read_regs(struct pca953x_chip *chip, int reg, u8 *val)
259 {
260 	int ret;
261 
262 	ret = chip->read_regs(chip, reg, val);
263 	if (ret < 0) {
264 		dev_err(&chip->client->dev, "failed reading register\n");
265 		return ret;
266 	}
267 
268 	return 0;
269 }
270 
271 static int pca953x_gpio_direction_input(struct gpio_chip *gc, unsigned off)
272 {
273 	struct pca953x_chip *chip = gpiochip_get_data(gc);
274 	u8 reg_val;
275 	int ret;
276 
277 	mutex_lock(&chip->i2c_lock);
278 	reg_val = chip->reg_direction[off / BANK_SZ] | (1u << (off % BANK_SZ));
279 
280 	ret = pca953x_write_single(chip, chip->regs->direction, reg_val, off);
281 	if (ret)
282 		goto exit;
283 
284 	chip->reg_direction[off / BANK_SZ] = reg_val;
285 exit:
286 	mutex_unlock(&chip->i2c_lock);
287 	return ret;
288 }
289 
290 static int pca953x_gpio_direction_output(struct gpio_chip *gc,
291 		unsigned off, int val)
292 {
293 	struct pca953x_chip *chip = gpiochip_get_data(gc);
294 	u8 reg_val;
295 	int ret;
296 
297 	mutex_lock(&chip->i2c_lock);
298 	/* set output level */
299 	if (val)
300 		reg_val = chip->reg_output[off / BANK_SZ]
301 			| (1u << (off % BANK_SZ));
302 	else
303 		reg_val = chip->reg_output[off / BANK_SZ]
304 			& ~(1u << (off % BANK_SZ));
305 
306 	ret = pca953x_write_single(chip, chip->regs->output, reg_val, off);
307 	if (ret)
308 		goto exit;
309 
310 	chip->reg_output[off / BANK_SZ] = reg_val;
311 
312 	/* then direction */
313 	reg_val = chip->reg_direction[off / BANK_SZ] & ~(1u << (off % BANK_SZ));
314 	ret = pca953x_write_single(chip, chip->regs->direction, reg_val, off);
315 	if (ret)
316 		goto exit;
317 
318 	chip->reg_direction[off / BANK_SZ] = reg_val;
319 exit:
320 	mutex_unlock(&chip->i2c_lock);
321 	return ret;
322 }
323 
324 static int pca953x_gpio_get_value(struct gpio_chip *gc, unsigned off)
325 {
326 	struct pca953x_chip *chip = gpiochip_get_data(gc);
327 	u32 reg_val;
328 	int ret;
329 
330 	mutex_lock(&chip->i2c_lock);
331 	ret = pca953x_read_single(chip, chip->regs->input, &reg_val, off);
332 	mutex_unlock(&chip->i2c_lock);
333 	if (ret < 0) {
334 		/* NOTE:  diagnostic already emitted; that's all we should
335 		 * do unless gpio_*_value_cansleep() calls become different
336 		 * from their nonsleeping siblings (and report faults).
337 		 */
338 		return 0;
339 	}
340 
341 	return (reg_val & (1u << (off % BANK_SZ))) ? 1 : 0;
342 }
343 
344 static void pca953x_gpio_set_value(struct gpio_chip *gc, unsigned off, int val)
345 {
346 	struct pca953x_chip *chip = gpiochip_get_data(gc);
347 	u8 reg_val;
348 	int ret;
349 
350 	mutex_lock(&chip->i2c_lock);
351 	if (val)
352 		reg_val = chip->reg_output[off / BANK_SZ]
353 			| (1u << (off % BANK_SZ));
354 	else
355 		reg_val = chip->reg_output[off / BANK_SZ]
356 			& ~(1u << (off % BANK_SZ));
357 
358 	ret = pca953x_write_single(chip, chip->regs->output, reg_val, off);
359 	if (ret)
360 		goto exit;
361 
362 	chip->reg_output[off / BANK_SZ] = reg_val;
363 exit:
364 	mutex_unlock(&chip->i2c_lock);
365 }
366 
367 static int pca953x_gpio_get_direction(struct gpio_chip *gc, unsigned off)
368 {
369 	struct pca953x_chip *chip = gpiochip_get_data(gc);
370 	u32 reg_val;
371 	int ret;
372 
373 	mutex_lock(&chip->i2c_lock);
374 	ret = pca953x_read_single(chip, chip->regs->direction, &reg_val, off);
375 	mutex_unlock(&chip->i2c_lock);
376 	if (ret < 0)
377 		return ret;
378 
379 	return !!(reg_val & (1u << (off % BANK_SZ)));
380 }
381 
382 static void pca953x_gpio_set_multiple(struct gpio_chip *gc,
383 				      unsigned long *mask, unsigned long *bits)
384 {
385 	struct pca953x_chip *chip = gpiochip_get_data(gc);
386 	unsigned int bank_mask, bank_val;
387 	int bank_shift, bank;
388 	u8 reg_val[MAX_BANK];
389 	int ret;
390 
391 	bank_shift = fls((chip->gpio_chip.ngpio - 1) / BANK_SZ);
392 
393 	mutex_lock(&chip->i2c_lock);
394 	memcpy(reg_val, chip->reg_output, NBANK(chip));
395 	for (bank = 0; bank < NBANK(chip); bank++) {
396 		bank_mask = mask[bank / sizeof(*mask)] >>
397 			   ((bank % sizeof(*mask)) * 8);
398 		if (bank_mask) {
399 			bank_val = bits[bank / sizeof(*bits)] >>
400 				  ((bank % sizeof(*bits)) * 8);
401 			bank_val &= bank_mask;
402 			reg_val[bank] = (reg_val[bank] & ~bank_mask) | bank_val;
403 		}
404 	}
405 
406 	ret = i2c_smbus_write_i2c_block_data(chip->client,
407 					     chip->regs->output << bank_shift,
408 					     NBANK(chip), reg_val);
409 	if (ret)
410 		goto exit;
411 
412 	memcpy(chip->reg_output, reg_val, NBANK(chip));
413 exit:
414 	mutex_unlock(&chip->i2c_lock);
415 }
416 
417 static void pca953x_setup_gpio(struct pca953x_chip *chip, int gpios)
418 {
419 	struct gpio_chip *gc;
420 
421 	gc = &chip->gpio_chip;
422 
423 	gc->direction_input  = pca953x_gpio_direction_input;
424 	gc->direction_output = pca953x_gpio_direction_output;
425 	gc->get = pca953x_gpio_get_value;
426 	gc->set = pca953x_gpio_set_value;
427 	gc->get_direction = pca953x_gpio_get_direction;
428 	gc->set_multiple = pca953x_gpio_set_multiple;
429 	gc->can_sleep = true;
430 
431 	gc->base = chip->gpio_start;
432 	gc->ngpio = gpios;
433 	gc->label = chip->client->name;
434 	gc->parent = &chip->client->dev;
435 	gc->owner = THIS_MODULE;
436 	gc->names = chip->names;
437 }
438 
439 #ifdef CONFIG_GPIO_PCA953X_IRQ
440 static void pca953x_irq_mask(struct irq_data *d)
441 {
442 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
443 	struct pca953x_chip *chip = gpiochip_get_data(gc);
444 
445 	chip->irq_mask[d->hwirq / BANK_SZ] &= ~(1 << (d->hwirq % BANK_SZ));
446 }
447 
448 static void pca953x_irq_unmask(struct irq_data *d)
449 {
450 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
451 	struct pca953x_chip *chip = gpiochip_get_data(gc);
452 
453 	chip->irq_mask[d->hwirq / BANK_SZ] |= 1 << (d->hwirq % BANK_SZ);
454 }
455 
456 static void pca953x_irq_bus_lock(struct irq_data *d)
457 {
458 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
459 	struct pca953x_chip *chip = gpiochip_get_data(gc);
460 
461 	mutex_lock(&chip->irq_lock);
462 }
463 
464 static void pca953x_irq_bus_sync_unlock(struct irq_data *d)
465 {
466 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
467 	struct pca953x_chip *chip = gpiochip_get_data(gc);
468 	u8 new_irqs;
469 	int level, i;
470 	u8 invert_irq_mask[MAX_BANK];
471 
472 	if (chip->driver_data & PCA_PCAL) {
473 		/* Enable latch on interrupt-enabled inputs */
474 		pca953x_write_regs(chip, PCAL953X_IN_LATCH, chip->irq_mask);
475 
476 		for (i = 0; i < NBANK(chip); i++)
477 			invert_irq_mask[i] = ~chip->irq_mask[i];
478 
479 		/* Unmask enabled interrupts */
480 		pca953x_write_regs(chip, PCAL953X_INT_MASK, invert_irq_mask);
481 	}
482 
483 	/* Look for any newly setup interrupt */
484 	for (i = 0; i < NBANK(chip); i++) {
485 		new_irqs = chip->irq_trig_fall[i] | chip->irq_trig_raise[i];
486 		new_irqs &= ~chip->reg_direction[i];
487 
488 		while (new_irqs) {
489 			level = __ffs(new_irqs);
490 			pca953x_gpio_direction_input(&chip->gpio_chip,
491 							level + (BANK_SZ * i));
492 			new_irqs &= ~(1 << level);
493 		}
494 	}
495 
496 	mutex_unlock(&chip->irq_lock);
497 }
498 
499 static int pca953x_irq_set_type(struct irq_data *d, unsigned int type)
500 {
501 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
502 	struct pca953x_chip *chip = gpiochip_get_data(gc);
503 	int bank_nb = d->hwirq / BANK_SZ;
504 	u8 mask = 1 << (d->hwirq % BANK_SZ);
505 
506 	if (!(type & IRQ_TYPE_EDGE_BOTH)) {
507 		dev_err(&chip->client->dev, "irq %d: unsupported type %d\n",
508 			d->irq, type);
509 		return -EINVAL;
510 	}
511 
512 	if (type & IRQ_TYPE_EDGE_FALLING)
513 		chip->irq_trig_fall[bank_nb] |= mask;
514 	else
515 		chip->irq_trig_fall[bank_nb] &= ~mask;
516 
517 	if (type & IRQ_TYPE_EDGE_RISING)
518 		chip->irq_trig_raise[bank_nb] |= mask;
519 	else
520 		chip->irq_trig_raise[bank_nb] &= ~mask;
521 
522 	return 0;
523 }
524 
525 static struct irq_chip pca953x_irq_chip = {
526 	.name			= "pca953x",
527 	.irq_mask		= pca953x_irq_mask,
528 	.irq_unmask		= pca953x_irq_unmask,
529 	.irq_bus_lock		= pca953x_irq_bus_lock,
530 	.irq_bus_sync_unlock	= pca953x_irq_bus_sync_unlock,
531 	.irq_set_type		= pca953x_irq_set_type,
532 };
533 
534 static bool pca953x_irq_pending(struct pca953x_chip *chip, u8 *pending)
535 {
536 	u8 cur_stat[MAX_BANK];
537 	u8 old_stat[MAX_BANK];
538 	bool pending_seen = false;
539 	bool trigger_seen = false;
540 	u8 trigger[MAX_BANK];
541 	int ret, i;
542 
543 	if (chip->driver_data & PCA_PCAL) {
544 		/* Read the current interrupt status from the device */
545 		ret = pca953x_read_regs(chip, PCAL953X_INT_STAT, trigger);
546 		if (ret)
547 			return false;
548 
549 		/* Check latched inputs and clear interrupt status */
550 		ret = pca953x_read_regs(chip, PCA953X_INPUT, cur_stat);
551 		if (ret)
552 			return false;
553 
554 		for (i = 0; i < NBANK(chip); i++) {
555 			/* Apply filter for rising/falling edge selection */
556 			pending[i] = (~cur_stat[i] & chip->irq_trig_fall[i]) |
557 				(cur_stat[i] & chip->irq_trig_raise[i]);
558 			pending[i] &= trigger[i];
559 			if (pending[i])
560 				pending_seen = true;
561 		}
562 
563 		return pending_seen;
564 	}
565 
566 	ret = pca953x_read_regs(chip, chip->regs->input, cur_stat);
567 	if (ret)
568 		return false;
569 
570 	/* Remove output pins from the equation */
571 	for (i = 0; i < NBANK(chip); i++)
572 		cur_stat[i] &= chip->reg_direction[i];
573 
574 	memcpy(old_stat, chip->irq_stat, NBANK(chip));
575 
576 	for (i = 0; i < NBANK(chip); i++) {
577 		trigger[i] = (cur_stat[i] ^ old_stat[i]) & chip->irq_mask[i];
578 		if (trigger[i])
579 			trigger_seen = true;
580 	}
581 
582 	if (!trigger_seen)
583 		return false;
584 
585 	memcpy(chip->irq_stat, cur_stat, NBANK(chip));
586 
587 	for (i = 0; i < NBANK(chip); i++) {
588 		pending[i] = (old_stat[i] & chip->irq_trig_fall[i]) |
589 			(cur_stat[i] & chip->irq_trig_raise[i]);
590 		pending[i] &= trigger[i];
591 		if (pending[i])
592 			pending_seen = true;
593 	}
594 
595 	return pending_seen;
596 }
597 
598 static irqreturn_t pca953x_irq_handler(int irq, void *devid)
599 {
600 	struct pca953x_chip *chip = devid;
601 	u8 pending[MAX_BANK];
602 	u8 level;
603 	unsigned nhandled = 0;
604 	int i;
605 
606 	if (!pca953x_irq_pending(chip, pending))
607 		return IRQ_NONE;
608 
609 	for (i = 0; i < NBANK(chip); i++) {
610 		while (pending[i]) {
611 			level = __ffs(pending[i]);
612 			handle_nested_irq(irq_find_mapping(chip->gpio_chip.irq.domain,
613 							level + (BANK_SZ * i)));
614 			pending[i] &= ~(1 << level);
615 			nhandled++;
616 		}
617 	}
618 
619 	return (nhandled > 0) ? IRQ_HANDLED : IRQ_NONE;
620 }
621 
622 static int pca953x_irq_setup(struct pca953x_chip *chip,
623 			     int irq_base)
624 {
625 	struct i2c_client *client = chip->client;
626 	int ret, i;
627 
628 	if (client->irq && irq_base != -1
629 			&& (chip->driver_data & PCA_INT)) {
630 		ret = pca953x_read_regs(chip,
631 					chip->regs->input, chip->irq_stat);
632 		if (ret)
633 			return ret;
634 
635 		/*
636 		 * There is no way to know which GPIO line generated the
637 		 * interrupt.  We have to rely on the previous read for
638 		 * this purpose.
639 		 */
640 		for (i = 0; i < NBANK(chip); i++)
641 			chip->irq_stat[i] &= chip->reg_direction[i];
642 		mutex_init(&chip->irq_lock);
643 
644 		ret = devm_request_threaded_irq(&client->dev,
645 					client->irq,
646 					   NULL,
647 					   pca953x_irq_handler,
648 					   IRQF_TRIGGER_LOW | IRQF_ONESHOT |
649 						   IRQF_SHARED,
650 					   dev_name(&client->dev), chip);
651 		if (ret) {
652 			dev_err(&client->dev, "failed to request irq %d\n",
653 				client->irq);
654 			return ret;
655 		}
656 
657 		ret =  gpiochip_irqchip_add_nested(&chip->gpio_chip,
658 						   &pca953x_irq_chip,
659 						   irq_base,
660 						   handle_simple_irq,
661 						   IRQ_TYPE_NONE);
662 		if (ret) {
663 			dev_err(&client->dev,
664 				"could not connect irqchip to gpiochip\n");
665 			return ret;
666 		}
667 
668 		gpiochip_set_nested_irqchip(&chip->gpio_chip,
669 					    &pca953x_irq_chip,
670 					    client->irq);
671 	}
672 
673 	return 0;
674 }
675 
676 #else /* CONFIG_GPIO_PCA953X_IRQ */
677 static int pca953x_irq_setup(struct pca953x_chip *chip,
678 			     int irq_base)
679 {
680 	struct i2c_client *client = chip->client;
681 
682 	if (irq_base != -1 && (chip->driver_data & PCA_INT))
683 		dev_warn(&client->dev, "interrupt support not compiled in\n");
684 
685 	return 0;
686 }
687 #endif
688 
689 static int device_pca953x_init(struct pca953x_chip *chip, u32 invert)
690 {
691 	int ret;
692 	u8 val[MAX_BANK];
693 
694 	chip->regs = &pca953x_regs;
695 
696 	ret = pca953x_read_regs(chip, chip->regs->output, chip->reg_output);
697 	if (ret)
698 		goto out;
699 
700 	ret = pca953x_read_regs(chip, chip->regs->direction,
701 				chip->reg_direction);
702 	if (ret)
703 		goto out;
704 
705 	/* set platform specific polarity inversion */
706 	if (invert)
707 		memset(val, 0xFF, NBANK(chip));
708 	else
709 		memset(val, 0, NBANK(chip));
710 
711 	ret = pca953x_write_regs(chip, PCA953X_INVERT, val);
712 out:
713 	return ret;
714 }
715 
716 static int device_pca957x_init(struct pca953x_chip *chip, u32 invert)
717 {
718 	int ret;
719 	u8 val[MAX_BANK];
720 
721 	chip->regs = &pca957x_regs;
722 
723 	ret = pca953x_read_regs(chip, chip->regs->output, chip->reg_output);
724 	if (ret)
725 		goto out;
726 	ret = pca953x_read_regs(chip, chip->regs->direction,
727 				chip->reg_direction);
728 	if (ret)
729 		goto out;
730 
731 	/* set platform specific polarity inversion */
732 	if (invert)
733 		memset(val, 0xFF, NBANK(chip));
734 	else
735 		memset(val, 0, NBANK(chip));
736 	ret = pca953x_write_regs(chip, PCA957X_INVRT, val);
737 	if (ret)
738 		goto out;
739 
740 	/* To enable register 6, 7 to control pull up and pull down */
741 	memset(val, 0x02, NBANK(chip));
742 	ret = pca953x_write_regs(chip, PCA957X_BKEN, val);
743 	if (ret)
744 		goto out;
745 
746 	return 0;
747 out:
748 	return ret;
749 }
750 
751 static const struct of_device_id pca953x_dt_ids[];
752 
753 static int pca953x_probe(struct i2c_client *client,
754 				   const struct i2c_device_id *i2c_id)
755 {
756 	struct pca953x_platform_data *pdata;
757 	struct pca953x_chip *chip;
758 	int irq_base = 0;
759 	int ret;
760 	u32 invert = 0;
761 	struct regulator *reg;
762 
763 	chip = devm_kzalloc(&client->dev,
764 			sizeof(struct pca953x_chip), GFP_KERNEL);
765 	if (chip == NULL)
766 		return -ENOMEM;
767 
768 	pdata = dev_get_platdata(&client->dev);
769 	if (pdata) {
770 		irq_base = pdata->irq_base;
771 		chip->gpio_start = pdata->gpio_base;
772 		invert = pdata->invert;
773 		chip->names = pdata->names;
774 	} else {
775 		struct gpio_desc *reset_gpio;
776 
777 		chip->gpio_start = -1;
778 		irq_base = 0;
779 
780 		/*
781 		 * See if we need to de-assert a reset pin.
782 		 *
783 		 * There is no known ACPI-enabled platforms that are
784 		 * using "reset" GPIO. Otherwise any of those platform
785 		 * must use _DSD method with corresponding property.
786 		 */
787 		reset_gpio = devm_gpiod_get_optional(&client->dev, "reset",
788 						     GPIOD_OUT_LOW);
789 		if (IS_ERR(reset_gpio))
790 			return PTR_ERR(reset_gpio);
791 	}
792 
793 	chip->client = client;
794 
795 	reg = devm_regulator_get(&client->dev, "vcc");
796 	if (IS_ERR(reg)) {
797 		ret = PTR_ERR(reg);
798 		if (ret != -EPROBE_DEFER)
799 			dev_err(&client->dev, "reg get err: %d\n", ret);
800 		return ret;
801 	}
802 	ret = regulator_enable(reg);
803 	if (ret) {
804 		dev_err(&client->dev, "reg en err: %d\n", ret);
805 		return ret;
806 	}
807 	chip->regulator = reg;
808 
809 	if (i2c_id) {
810 		chip->driver_data = i2c_id->driver_data;
811 	} else {
812 		const struct acpi_device_id *acpi_id;
813 		const struct of_device_id *match;
814 
815 		match = of_match_device(pca953x_dt_ids, &client->dev);
816 		if (match) {
817 			chip->driver_data = (int)(uintptr_t)match->data;
818 		} else {
819 			acpi_id = acpi_match_device(pca953x_acpi_ids, &client->dev);
820 			if (!acpi_id) {
821 				ret = -ENODEV;
822 				goto err_exit;
823 			}
824 
825 			chip->driver_data = acpi_id->driver_data;
826 		}
827 	}
828 
829 	mutex_init(&chip->i2c_lock);
830 	/*
831 	 * In case we have an i2c-mux controlled by a GPIO provided by an
832 	 * expander using the same driver higher on the device tree, read the
833 	 * i2c adapter nesting depth and use the retrieved value as lockdep
834 	 * subclass for chip->i2c_lock.
835 	 *
836 	 * REVISIT: This solution is not complete. It protects us from lockdep
837 	 * false positives when the expander controlling the i2c-mux is on
838 	 * a different level on the device tree, but not when it's on the same
839 	 * level on a different branch (in which case the subclass number
840 	 * would be the same).
841 	 *
842 	 * TODO: Once a correct solution is developed, a similar fix should be
843 	 * applied to all other i2c-controlled GPIO expanders (and potentially
844 	 * regmap-i2c).
845 	 */
846 	lockdep_set_subclass(&chip->i2c_lock,
847 			     i2c_adapter_depth(client->adapter));
848 
849 	/* initialize cached registers from their original values.
850 	 * we can't share this chip with another i2c master.
851 	 */
852 	pca953x_setup_gpio(chip, chip->driver_data & PCA_GPIO_MASK);
853 
854 	if (chip->gpio_chip.ngpio <= 8) {
855 		chip->write_regs = pca953x_write_regs_8;
856 		chip->read_regs = pca953x_read_regs_8;
857 	} else if (chip->gpio_chip.ngpio >= 24) {
858 		chip->write_regs = pca953x_write_regs_24;
859 		chip->read_regs = pca953x_read_regs_24;
860 	} else {
861 		if (PCA_CHIP_TYPE(chip->driver_data) == PCA953X_TYPE)
862 			chip->write_regs = pca953x_write_regs_16;
863 		else
864 			chip->write_regs = pca957x_write_regs_16;
865 		chip->read_regs = pca953x_read_regs_16;
866 	}
867 
868 	if (PCA_CHIP_TYPE(chip->driver_data) == PCA953X_TYPE)
869 		ret = device_pca953x_init(chip, invert);
870 	else
871 		ret = device_pca957x_init(chip, invert);
872 	if (ret)
873 		goto err_exit;
874 
875 	ret = devm_gpiochip_add_data(&client->dev, &chip->gpio_chip, chip);
876 	if (ret)
877 		goto err_exit;
878 
879 	ret = pca953x_irq_setup(chip, irq_base);
880 	if (ret)
881 		goto err_exit;
882 
883 	if (pdata && pdata->setup) {
884 		ret = pdata->setup(client, chip->gpio_chip.base,
885 				chip->gpio_chip.ngpio, pdata->context);
886 		if (ret < 0)
887 			dev_warn(&client->dev, "setup failed, %d\n", ret);
888 	}
889 
890 	i2c_set_clientdata(client, chip);
891 	return 0;
892 
893 err_exit:
894 	regulator_disable(chip->regulator);
895 	return ret;
896 }
897 
898 static int pca953x_remove(struct i2c_client *client)
899 {
900 	struct pca953x_platform_data *pdata = dev_get_platdata(&client->dev);
901 	struct pca953x_chip *chip = i2c_get_clientdata(client);
902 	int ret;
903 
904 	if (pdata && pdata->teardown) {
905 		ret = pdata->teardown(client, chip->gpio_chip.base,
906 				chip->gpio_chip.ngpio, pdata->context);
907 		if (ret < 0)
908 			dev_err(&client->dev, "%s failed, %d\n",
909 					"teardown", ret);
910 	} else {
911 		ret = 0;
912 	}
913 
914 	regulator_disable(chip->regulator);
915 
916 	return ret;
917 }
918 
919 /* convenience to stop overlong match-table lines */
920 #define OF_953X(__nrgpio, __int) (void *)(__nrgpio | PCA953X_TYPE | __int)
921 #define OF_957X(__nrgpio, __int) (void *)(__nrgpio | PCA957X_TYPE | __int)
922 
923 static const struct of_device_id pca953x_dt_ids[] = {
924 	{ .compatible = "nxp,pca9505", .data = OF_953X(40, PCA_INT), },
925 	{ .compatible = "nxp,pca9534", .data = OF_953X( 8, PCA_INT), },
926 	{ .compatible = "nxp,pca9535", .data = OF_953X(16, PCA_INT), },
927 	{ .compatible = "nxp,pca9536", .data = OF_953X( 4, 0), },
928 	{ .compatible = "nxp,pca9537", .data = OF_953X( 4, PCA_INT), },
929 	{ .compatible = "nxp,pca9538", .data = OF_953X( 8, PCA_INT), },
930 	{ .compatible = "nxp,pca9539", .data = OF_953X(16, PCA_INT), },
931 	{ .compatible = "nxp,pca9554", .data = OF_953X( 8, PCA_INT), },
932 	{ .compatible = "nxp,pca9555", .data = OF_953X(16, PCA_INT), },
933 	{ .compatible = "nxp,pca9556", .data = OF_953X( 8, 0), },
934 	{ .compatible = "nxp,pca9557", .data = OF_953X( 8, 0), },
935 	{ .compatible = "nxp,pca9574", .data = OF_957X( 8, PCA_INT), },
936 	{ .compatible = "nxp,pca9575", .data = OF_957X(16, PCA_INT), },
937 	{ .compatible = "nxp,pca9698", .data = OF_953X(40, 0), },
938 
939 	{ .compatible = "nxp,pcal6524", .data = OF_953X(24, PCA_INT), },
940 	{ .compatible = "nxp,pcal9555a", .data = OF_953X(16, PCA_INT), },
941 
942 	{ .compatible = "maxim,max7310", .data = OF_953X( 8, 0), },
943 	{ .compatible = "maxim,max7312", .data = OF_953X(16, PCA_INT), },
944 	{ .compatible = "maxim,max7313", .data = OF_953X(16, PCA_INT), },
945 	{ .compatible = "maxim,max7315", .data = OF_953X( 8, PCA_INT), },
946 	{ .compatible = "maxim,max7318", .data = OF_953X(16, PCA_INT), },
947 
948 	{ .compatible = "ti,pca6107", .data = OF_953X( 8, PCA_INT), },
949 	{ .compatible = "ti,pca9536", .data = OF_953X( 4, 0), },
950 	{ .compatible = "ti,tca6408", .data = OF_953X( 8, PCA_INT), },
951 	{ .compatible = "ti,tca6416", .data = OF_953X(16, PCA_INT), },
952 	{ .compatible = "ti,tca6424", .data = OF_953X(24, PCA_INT), },
953 
954 	{ .compatible = "onnn,pca9654", .data = OF_953X( 8, PCA_INT), },
955 
956 	{ .compatible = "exar,xra1202", .data = OF_953X( 8, 0), },
957 	{ }
958 };
959 
960 MODULE_DEVICE_TABLE(of, pca953x_dt_ids);
961 
962 static struct i2c_driver pca953x_driver = {
963 	.driver = {
964 		.name	= "pca953x",
965 		.of_match_table = pca953x_dt_ids,
966 		.acpi_match_table = ACPI_PTR(pca953x_acpi_ids),
967 	},
968 	.probe		= pca953x_probe,
969 	.remove		= pca953x_remove,
970 	.id_table	= pca953x_id,
971 };
972 
973 static int __init pca953x_init(void)
974 {
975 	return i2c_add_driver(&pca953x_driver);
976 }
977 /* register after i2c postcore initcall and before
978  * subsys initcalls that may rely on these GPIOs
979  */
980 subsys_initcall(pca953x_init);
981 
982 static void __exit pca953x_exit(void)
983 {
984 	i2c_del_driver(&pca953x_driver);
985 }
986 module_exit(pca953x_exit);
987 
988 MODULE_AUTHOR("eric miao <eric.miao@marvell.com>");
989 MODULE_DESCRIPTION("GPIO expander driver for PCA953x");
990 MODULE_LICENSE("GPL");
991