xref: /openbmc/linux/drivers/gpio/gpio-pca953x.c (revision 4e1a33b1)
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/gpio/consumer.h>
18 #include <linux/interrupt.h>
19 #include <linux/i2c.h>
20 #include <linux/platform_data/pca953x.h>
21 #include <linux/slab.h>
22 #include <asm/unaligned.h>
23 #include <linux/of_platform.h>
24 #include <linux/acpi.h>
25 #include <linux/regulator/consumer.h>
26 
27 #define PCA953X_INPUT		0
28 #define PCA953X_OUTPUT		1
29 #define PCA953X_INVERT		2
30 #define PCA953X_DIRECTION	3
31 
32 #define REG_ADDR_AI		0x80
33 
34 #define PCA957X_IN		0
35 #define PCA957X_INVRT		1
36 #define PCA957X_BKEN		2
37 #define PCA957X_PUPD		3
38 #define PCA957X_CFG		4
39 #define PCA957X_OUT		5
40 #define PCA957X_MSK		6
41 #define PCA957X_INTS		7
42 
43 #define PCAL953X_IN_LATCH	34
44 #define PCAL953X_INT_MASK	37
45 #define PCAL953X_INT_STAT	38
46 
47 #define PCA_GPIO_MASK		0x00FF
48 #define PCA_INT			0x0100
49 #define PCA_PCAL		0x0200
50 #define PCA953X_TYPE		0x1000
51 #define PCA957X_TYPE		0x2000
52 #define PCA_TYPE_MASK		0xF000
53 
54 #define PCA_CHIP_TYPE(x)	((x) & PCA_TYPE_MASK)
55 
56 static const struct i2c_device_id pca953x_id[] = {
57 	{ "pca9505", 40 | PCA953X_TYPE | PCA_INT, },
58 	{ "pca9534", 8  | PCA953X_TYPE | PCA_INT, },
59 	{ "pca9535", 16 | PCA953X_TYPE | PCA_INT, },
60 	{ "pca9536", 4  | PCA953X_TYPE, },
61 	{ "pca9537", 4  | PCA953X_TYPE | PCA_INT, },
62 	{ "pca9538", 8  | PCA953X_TYPE | PCA_INT, },
63 	{ "pca9539", 16 | PCA953X_TYPE | PCA_INT, },
64 	{ "pca9554", 8  | PCA953X_TYPE | PCA_INT, },
65 	{ "pca9555", 16 | PCA953X_TYPE | PCA_INT, },
66 	{ "pca9556", 8  | PCA953X_TYPE, },
67 	{ "pca9557", 8  | PCA953X_TYPE, },
68 	{ "pca9574", 8  | PCA957X_TYPE | PCA_INT, },
69 	{ "pca9575", 16 | PCA957X_TYPE | PCA_INT, },
70 	{ "pca9698", 40 | PCA953X_TYPE, },
71 
72 	{ "pcal9555a", 16 | PCA953X_TYPE | PCA_INT | PCA_PCAL, },
73 
74 	{ "max7310", 8  | PCA953X_TYPE, },
75 	{ "max7312", 16 | PCA953X_TYPE | PCA_INT, },
76 	{ "max7313", 16 | PCA953X_TYPE | PCA_INT, },
77 	{ "max7315", 8  | PCA953X_TYPE | PCA_INT, },
78 	{ "max7318", 16 | PCA953X_TYPE | PCA_INT, },
79 	{ "pca6107", 8  | PCA953X_TYPE | PCA_INT, },
80 	{ "tca6408", 8  | PCA953X_TYPE | PCA_INT, },
81 	{ "tca6416", 16 | PCA953X_TYPE | PCA_INT, },
82 	{ "tca6424", 24 | PCA953X_TYPE | PCA_INT, },
83 	{ "tca9539", 16 | PCA953X_TYPE | PCA_INT, },
84 	{ "xra1202", 8  | PCA953X_TYPE },
85 	{ }
86 };
87 MODULE_DEVICE_TABLE(i2c, pca953x_id);
88 
89 static const struct acpi_device_id pca953x_acpi_ids[] = {
90 	{ "INT3491", 16 | PCA953X_TYPE | PCA_INT | PCA_PCAL, },
91 	{ }
92 };
93 MODULE_DEVICE_TABLE(acpi, pca953x_acpi_ids);
94 
95 #define MAX_BANK 5
96 #define BANK_SZ 8
97 
98 #define NBANK(chip) DIV_ROUND_UP(chip->gpio_chip.ngpio, BANK_SZ)
99 
100 struct pca953x_reg_config {
101 	int direction;
102 	int output;
103 	int input;
104 };
105 
106 static const struct pca953x_reg_config pca953x_regs = {
107 	.direction = PCA953X_DIRECTION,
108 	.output = PCA953X_OUTPUT,
109 	.input = PCA953X_INPUT,
110 };
111 
112 static const struct pca953x_reg_config pca957x_regs = {
113 	.direction = PCA957X_CFG,
114 	.output = PCA957X_OUT,
115 	.input = PCA957X_IN,
116 };
117 
118 struct pca953x_chip {
119 	unsigned gpio_start;
120 	u8 reg_output[MAX_BANK];
121 	u8 reg_direction[MAX_BANK];
122 	struct mutex i2c_lock;
123 
124 #ifdef CONFIG_GPIO_PCA953X_IRQ
125 	struct mutex irq_lock;
126 	u8 irq_mask[MAX_BANK];
127 	u8 irq_stat[MAX_BANK];
128 	u8 irq_trig_raise[MAX_BANK];
129 	u8 irq_trig_fall[MAX_BANK];
130 #endif
131 
132 	struct i2c_client *client;
133 	struct gpio_chip gpio_chip;
134 	const char *const *names;
135 	unsigned long driver_data;
136 	struct regulator *regulator;
137 
138 	const struct pca953x_reg_config *regs;
139 
140 	int (*write_regs)(struct pca953x_chip *, int, u8 *);
141 	int (*read_regs)(struct pca953x_chip *, int, u8 *);
142 };
143 
144 static int pca953x_read_single(struct pca953x_chip *chip, int reg, u32 *val,
145 				int off)
146 {
147 	int ret;
148 	int bank_shift = fls((chip->gpio_chip.ngpio - 1) / BANK_SZ);
149 	int offset = off / BANK_SZ;
150 
151 	ret = i2c_smbus_read_byte_data(chip->client,
152 				(reg << bank_shift) + offset);
153 	*val = ret;
154 
155 	if (ret < 0) {
156 		dev_err(&chip->client->dev, "failed reading register\n");
157 		return ret;
158 	}
159 
160 	return 0;
161 }
162 
163 static int pca953x_write_single(struct pca953x_chip *chip, int reg, u32 val,
164 				int off)
165 {
166 	int ret;
167 	int bank_shift = fls((chip->gpio_chip.ngpio - 1) / BANK_SZ);
168 	int offset = off / BANK_SZ;
169 
170 	ret = i2c_smbus_write_byte_data(chip->client,
171 					(reg << bank_shift) + offset, val);
172 
173 	if (ret < 0) {
174 		dev_err(&chip->client->dev, "failed writing register\n");
175 		return ret;
176 	}
177 
178 	return 0;
179 }
180 
181 static int pca953x_write_regs_8(struct pca953x_chip *chip, int reg, u8 *val)
182 {
183 	return i2c_smbus_write_byte_data(chip->client, reg, *val);
184 }
185 
186 static int pca953x_write_regs_16(struct pca953x_chip *chip, int reg, u8 *val)
187 {
188 	__le16 word = cpu_to_le16(get_unaligned((u16 *)val));
189 
190 	return i2c_smbus_write_word_data(chip->client,
191 					 reg << 1, (__force u16)word);
192 }
193 
194 static int pca957x_write_regs_16(struct pca953x_chip *chip, int reg, u8 *val)
195 {
196 	int ret;
197 
198 	ret = i2c_smbus_write_byte_data(chip->client, reg << 1, val[0]);
199 	if (ret < 0)
200 		return ret;
201 
202 	return i2c_smbus_write_byte_data(chip->client, (reg << 1) + 1, val[1]);
203 }
204 
205 static int pca953x_write_regs_24(struct pca953x_chip *chip, int reg, u8 *val)
206 {
207 	int bank_shift = fls((chip->gpio_chip.ngpio - 1) / BANK_SZ);
208 
209 	return i2c_smbus_write_i2c_block_data(chip->client,
210 					      (reg << bank_shift) | REG_ADDR_AI,
211 					      NBANK(chip), val);
212 }
213 
214 static int pca953x_write_regs(struct pca953x_chip *chip, int reg, u8 *val)
215 {
216 	int ret = 0;
217 
218 	ret = chip->write_regs(chip, reg, val);
219 	if (ret < 0) {
220 		dev_err(&chip->client->dev, "failed writing register\n");
221 		return ret;
222 	}
223 
224 	return 0;
225 }
226 
227 static int pca953x_read_regs_8(struct pca953x_chip *chip, int reg, u8 *val)
228 {
229 	int ret;
230 
231 	ret = i2c_smbus_read_byte_data(chip->client, reg);
232 	*val = ret;
233 
234 	return ret;
235 }
236 
237 static int pca953x_read_regs_16(struct pca953x_chip *chip, int reg, u8 *val)
238 {
239 	int ret;
240 
241 	ret = i2c_smbus_read_word_data(chip->client, reg << 1);
242 	val[0] = (u16)ret & 0xFF;
243 	val[1] = (u16)ret >> 8;
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 void pca953x_gpio_set_multiple(struct gpio_chip *gc,
367 				      unsigned long *mask, unsigned long *bits)
368 {
369 	struct pca953x_chip *chip = gpiochip_get_data(gc);
370 	unsigned int bank_mask, bank_val;
371 	int bank_shift, bank;
372 	u8 reg_val[MAX_BANK];
373 	int ret;
374 
375 	bank_shift = fls((chip->gpio_chip.ngpio - 1) / BANK_SZ);
376 
377 	mutex_lock(&chip->i2c_lock);
378 	memcpy(reg_val, chip->reg_output, NBANK(chip));
379 	for (bank = 0; bank < NBANK(chip); bank++) {
380 		bank_mask = mask[bank / sizeof(*mask)] >>
381 			   ((bank % sizeof(*mask)) * 8);
382 		if (bank_mask) {
383 			bank_val = bits[bank / sizeof(*bits)] >>
384 				  ((bank % sizeof(*bits)) * 8);
385 			bank_val &= bank_mask;
386 			reg_val[bank] = (reg_val[bank] & ~bank_mask) | bank_val;
387 		}
388 	}
389 
390 	ret = i2c_smbus_write_i2c_block_data(chip->client,
391 					     chip->regs->output << bank_shift,
392 					     NBANK(chip), reg_val);
393 	if (ret)
394 		goto exit;
395 
396 	memcpy(chip->reg_output, reg_val, NBANK(chip));
397 exit:
398 	mutex_unlock(&chip->i2c_lock);
399 }
400 
401 static void pca953x_setup_gpio(struct pca953x_chip *chip, int gpios)
402 {
403 	struct gpio_chip *gc;
404 
405 	gc = &chip->gpio_chip;
406 
407 	gc->direction_input  = pca953x_gpio_direction_input;
408 	gc->direction_output = pca953x_gpio_direction_output;
409 	gc->get = pca953x_gpio_get_value;
410 	gc->set = pca953x_gpio_set_value;
411 	gc->set_multiple = pca953x_gpio_set_multiple;
412 	gc->can_sleep = true;
413 
414 	gc->base = chip->gpio_start;
415 	gc->ngpio = gpios;
416 	gc->label = chip->client->name;
417 	gc->parent = &chip->client->dev;
418 	gc->owner = THIS_MODULE;
419 	gc->names = chip->names;
420 }
421 
422 #ifdef CONFIG_GPIO_PCA953X_IRQ
423 static void pca953x_irq_mask(struct irq_data *d)
424 {
425 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
426 	struct pca953x_chip *chip = gpiochip_get_data(gc);
427 
428 	chip->irq_mask[d->hwirq / BANK_SZ] &= ~(1 << (d->hwirq % BANK_SZ));
429 }
430 
431 static void pca953x_irq_unmask(struct irq_data *d)
432 {
433 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
434 	struct pca953x_chip *chip = gpiochip_get_data(gc);
435 
436 	chip->irq_mask[d->hwirq / BANK_SZ] |= 1 << (d->hwirq % BANK_SZ);
437 }
438 
439 static void pca953x_irq_bus_lock(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 	mutex_lock(&chip->irq_lock);
445 }
446 
447 static void pca953x_irq_bus_sync_unlock(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 	u8 new_irqs;
452 	int level, i;
453 	u8 invert_irq_mask[MAX_BANK];
454 
455 	if (chip->driver_data & PCA_PCAL) {
456 		/* Enable latch on interrupt-enabled inputs */
457 		pca953x_write_regs(chip, PCAL953X_IN_LATCH, chip->irq_mask);
458 
459 		for (i = 0; i < NBANK(chip); i++)
460 			invert_irq_mask[i] = ~chip->irq_mask[i];
461 
462 		/* Unmask enabled interrupts */
463 		pca953x_write_regs(chip, PCAL953X_INT_MASK, invert_irq_mask);
464 	}
465 
466 	/* Look for any newly setup interrupt */
467 	for (i = 0; i < NBANK(chip); i++) {
468 		new_irqs = chip->irq_trig_fall[i] | chip->irq_trig_raise[i];
469 		new_irqs &= ~chip->reg_direction[i];
470 
471 		while (new_irqs) {
472 			level = __ffs(new_irqs);
473 			pca953x_gpio_direction_input(&chip->gpio_chip,
474 							level + (BANK_SZ * i));
475 			new_irqs &= ~(1 << level);
476 		}
477 	}
478 
479 	mutex_unlock(&chip->irq_lock);
480 }
481 
482 static int pca953x_irq_set_type(struct irq_data *d, unsigned int type)
483 {
484 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
485 	struct pca953x_chip *chip = gpiochip_get_data(gc);
486 	int bank_nb = d->hwirq / BANK_SZ;
487 	u8 mask = 1 << (d->hwirq % BANK_SZ);
488 
489 	if (!(type & IRQ_TYPE_EDGE_BOTH)) {
490 		dev_err(&chip->client->dev, "irq %d: unsupported type %d\n",
491 			d->irq, type);
492 		return -EINVAL;
493 	}
494 
495 	if (type & IRQ_TYPE_EDGE_FALLING)
496 		chip->irq_trig_fall[bank_nb] |= mask;
497 	else
498 		chip->irq_trig_fall[bank_nb] &= ~mask;
499 
500 	if (type & IRQ_TYPE_EDGE_RISING)
501 		chip->irq_trig_raise[bank_nb] |= mask;
502 	else
503 		chip->irq_trig_raise[bank_nb] &= ~mask;
504 
505 	return 0;
506 }
507 
508 static struct irq_chip pca953x_irq_chip = {
509 	.name			= "pca953x",
510 	.irq_mask		= pca953x_irq_mask,
511 	.irq_unmask		= pca953x_irq_unmask,
512 	.irq_bus_lock		= pca953x_irq_bus_lock,
513 	.irq_bus_sync_unlock	= pca953x_irq_bus_sync_unlock,
514 	.irq_set_type		= pca953x_irq_set_type,
515 };
516 
517 static bool pca953x_irq_pending(struct pca953x_chip *chip, u8 *pending)
518 {
519 	u8 cur_stat[MAX_BANK];
520 	u8 old_stat[MAX_BANK];
521 	bool pending_seen = false;
522 	bool trigger_seen = false;
523 	u8 trigger[MAX_BANK];
524 	int ret, i;
525 
526 	if (chip->driver_data & PCA_PCAL) {
527 		/* Read the current interrupt status from the device */
528 		ret = pca953x_read_regs(chip, PCAL953X_INT_STAT, trigger);
529 		if (ret)
530 			return false;
531 
532 		/* Check latched inputs and clear interrupt status */
533 		ret = pca953x_read_regs(chip, PCA953X_INPUT, cur_stat);
534 		if (ret)
535 			return false;
536 
537 		for (i = 0; i < NBANK(chip); i++) {
538 			/* Apply filter for rising/falling edge selection */
539 			pending[i] = (~cur_stat[i] & chip->irq_trig_fall[i]) |
540 				(cur_stat[i] & chip->irq_trig_raise[i]);
541 			pending[i] &= trigger[i];
542 			if (pending[i])
543 				pending_seen = true;
544 		}
545 
546 		return pending_seen;
547 	}
548 
549 	ret = pca953x_read_regs(chip, chip->regs->input, cur_stat);
550 	if (ret)
551 		return false;
552 
553 	/* Remove output pins from the equation */
554 	for (i = 0; i < NBANK(chip); i++)
555 		cur_stat[i] &= chip->reg_direction[i];
556 
557 	memcpy(old_stat, chip->irq_stat, NBANK(chip));
558 
559 	for (i = 0; i < NBANK(chip); i++) {
560 		trigger[i] = (cur_stat[i] ^ old_stat[i]) & chip->irq_mask[i];
561 		if (trigger[i])
562 			trigger_seen = true;
563 	}
564 
565 	if (!trigger_seen)
566 		return false;
567 
568 	memcpy(chip->irq_stat, cur_stat, NBANK(chip));
569 
570 	for (i = 0; i < NBANK(chip); i++) {
571 		pending[i] = (old_stat[i] & chip->irq_trig_fall[i]) |
572 			(cur_stat[i] & chip->irq_trig_raise[i]);
573 		pending[i] &= trigger[i];
574 		if (pending[i])
575 			pending_seen = true;
576 	}
577 
578 	return pending_seen;
579 }
580 
581 static irqreturn_t pca953x_irq_handler(int irq, void *devid)
582 {
583 	struct pca953x_chip *chip = devid;
584 	u8 pending[MAX_BANK];
585 	u8 level;
586 	unsigned nhandled = 0;
587 	int i;
588 
589 	if (!pca953x_irq_pending(chip, pending))
590 		return IRQ_NONE;
591 
592 	for (i = 0; i < NBANK(chip); i++) {
593 		while (pending[i]) {
594 			level = __ffs(pending[i]);
595 			handle_nested_irq(irq_find_mapping(chip->gpio_chip.irqdomain,
596 							level + (BANK_SZ * i)));
597 			pending[i] &= ~(1 << level);
598 			nhandled++;
599 		}
600 	}
601 
602 	return (nhandled > 0) ? IRQ_HANDLED : IRQ_NONE;
603 }
604 
605 static int pca953x_irq_setup(struct pca953x_chip *chip,
606 			     int irq_base)
607 {
608 	struct i2c_client *client = chip->client;
609 	int ret, i;
610 
611 	if (client->irq && irq_base != -1
612 			&& (chip->driver_data & PCA_INT)) {
613 		ret = pca953x_read_regs(chip,
614 					chip->regs->input, chip->irq_stat);
615 		if (ret)
616 			return ret;
617 
618 		/*
619 		 * There is no way to know which GPIO line generated the
620 		 * interrupt.  We have to rely on the previous read for
621 		 * this purpose.
622 		 */
623 		for (i = 0; i < NBANK(chip); i++)
624 			chip->irq_stat[i] &= chip->reg_direction[i];
625 		mutex_init(&chip->irq_lock);
626 
627 		ret = devm_request_threaded_irq(&client->dev,
628 					client->irq,
629 					   NULL,
630 					   pca953x_irq_handler,
631 					   IRQF_TRIGGER_LOW | IRQF_ONESHOT |
632 						   IRQF_SHARED,
633 					   dev_name(&client->dev), chip);
634 		if (ret) {
635 			dev_err(&client->dev, "failed to request irq %d\n",
636 				client->irq);
637 			return ret;
638 		}
639 
640 		ret =  gpiochip_irqchip_add_nested(&chip->gpio_chip,
641 						   &pca953x_irq_chip,
642 						   irq_base,
643 						   handle_simple_irq,
644 						   IRQ_TYPE_NONE);
645 		if (ret) {
646 			dev_err(&client->dev,
647 				"could not connect irqchip to gpiochip\n");
648 			return ret;
649 		}
650 
651 		gpiochip_set_nested_irqchip(&chip->gpio_chip,
652 					    &pca953x_irq_chip,
653 					    client->irq);
654 	}
655 
656 	return 0;
657 }
658 
659 #else /* CONFIG_GPIO_PCA953X_IRQ */
660 static int pca953x_irq_setup(struct pca953x_chip *chip,
661 			     int irq_base)
662 {
663 	struct i2c_client *client = chip->client;
664 
665 	if (irq_base != -1 && (chip->driver_data & PCA_INT))
666 		dev_warn(&client->dev, "interrupt support not compiled in\n");
667 
668 	return 0;
669 }
670 #endif
671 
672 static int device_pca953x_init(struct pca953x_chip *chip, u32 invert)
673 {
674 	int ret;
675 	u8 val[MAX_BANK];
676 
677 	chip->regs = &pca953x_regs;
678 
679 	ret = pca953x_read_regs(chip, chip->regs->output, chip->reg_output);
680 	if (ret)
681 		goto out;
682 
683 	ret = pca953x_read_regs(chip, chip->regs->direction,
684 				chip->reg_direction);
685 	if (ret)
686 		goto out;
687 
688 	/* set platform specific polarity inversion */
689 	if (invert)
690 		memset(val, 0xFF, NBANK(chip));
691 	else
692 		memset(val, 0, NBANK(chip));
693 
694 	ret = pca953x_write_regs(chip, PCA953X_INVERT, val);
695 out:
696 	return ret;
697 }
698 
699 static int device_pca957x_init(struct pca953x_chip *chip, u32 invert)
700 {
701 	int ret;
702 	u8 val[MAX_BANK];
703 
704 	chip->regs = &pca957x_regs;
705 
706 	ret = pca953x_read_regs(chip, chip->regs->output, chip->reg_output);
707 	if (ret)
708 		goto out;
709 	ret = pca953x_read_regs(chip, chip->regs->direction,
710 				chip->reg_direction);
711 	if (ret)
712 		goto out;
713 
714 	/* set platform specific polarity inversion */
715 	if (invert)
716 		memset(val, 0xFF, NBANK(chip));
717 	else
718 		memset(val, 0, NBANK(chip));
719 	ret = pca953x_write_regs(chip, PCA957X_INVRT, val);
720 	if (ret)
721 		goto out;
722 
723 	/* To enable register 6, 7 to control pull up and pull down */
724 	memset(val, 0x02, NBANK(chip));
725 	ret = pca953x_write_regs(chip, PCA957X_BKEN, val);
726 	if (ret)
727 		goto out;
728 
729 	return 0;
730 out:
731 	return ret;
732 }
733 
734 static const struct of_device_id pca953x_dt_ids[];
735 
736 static int pca953x_probe(struct i2c_client *client,
737 				   const struct i2c_device_id *i2c_id)
738 {
739 	struct pca953x_platform_data *pdata;
740 	struct pca953x_chip *chip;
741 	int irq_base = 0;
742 	int ret;
743 	u32 invert = 0;
744 	struct regulator *reg;
745 
746 	chip = devm_kzalloc(&client->dev,
747 			sizeof(struct pca953x_chip), GFP_KERNEL);
748 	if (chip == NULL)
749 		return -ENOMEM;
750 
751 	pdata = dev_get_platdata(&client->dev);
752 	if (pdata) {
753 		irq_base = pdata->irq_base;
754 		chip->gpio_start = pdata->gpio_base;
755 		invert = pdata->invert;
756 		chip->names = pdata->names;
757 	} else {
758 		struct gpio_desc *reset_gpio;
759 
760 		chip->gpio_start = -1;
761 		irq_base = 0;
762 
763 		/* See if we need to de-assert a reset pin */
764 		reset_gpio = devm_gpiod_get_optional(&client->dev, "reset",
765 						     GPIOD_OUT_LOW);
766 		if (IS_ERR(reset_gpio))
767 			return PTR_ERR(reset_gpio);
768 	}
769 
770 	chip->client = client;
771 
772 	reg = devm_regulator_get(&client->dev, "vcc");
773 	if (IS_ERR(reg)) {
774 		ret = PTR_ERR(reg);
775 		if (ret != -EPROBE_DEFER)
776 			dev_err(&client->dev, "reg get err: %d\n", ret);
777 		return ret;
778 	}
779 	ret = regulator_enable(reg);
780 	if (ret) {
781 		dev_err(&client->dev, "reg en err: %d\n", ret);
782 		return ret;
783 	}
784 	chip->regulator = reg;
785 
786 	if (i2c_id) {
787 		chip->driver_data = i2c_id->driver_data;
788 	} else {
789 		const struct acpi_device_id *acpi_id;
790 		const struct of_device_id *match;
791 
792 		match = of_match_device(pca953x_dt_ids, &client->dev);
793 		if (match) {
794 			chip->driver_data = (int)(uintptr_t)match->data;
795 		} else {
796 			acpi_id = acpi_match_device(pca953x_acpi_ids, &client->dev);
797 			if (!acpi_id) {
798 				ret = -ENODEV;
799 				goto err_exit;
800 			}
801 
802 			chip->driver_data = acpi_id->driver_data;
803 		}
804 	}
805 
806 	mutex_init(&chip->i2c_lock);
807 	/*
808 	 * In case we have an i2c-mux controlled by a GPIO provided by an
809 	 * expander using the same driver higher on the device tree, read the
810 	 * i2c adapter nesting depth and use the retrieved value as lockdep
811 	 * subclass for chip->i2c_lock.
812 	 *
813 	 * REVISIT: This solution is not complete. It protects us from lockdep
814 	 * false positives when the expander controlling the i2c-mux is on
815 	 * a different level on the device tree, but not when it's on the same
816 	 * level on a different branch (in which case the subclass number
817 	 * would be the same).
818 	 *
819 	 * TODO: Once a correct solution is developed, a similar fix should be
820 	 * applied to all other i2c-controlled GPIO expanders (and potentially
821 	 * regmap-i2c).
822 	 */
823 	lockdep_set_subclass(&chip->i2c_lock,
824 			     i2c_adapter_depth(client->adapter));
825 
826 	/* initialize cached registers from their original values.
827 	 * we can't share this chip with another i2c master.
828 	 */
829 	pca953x_setup_gpio(chip, chip->driver_data & PCA_GPIO_MASK);
830 
831 	if (chip->gpio_chip.ngpio <= 8) {
832 		chip->write_regs = pca953x_write_regs_8;
833 		chip->read_regs = pca953x_read_regs_8;
834 	} else if (chip->gpio_chip.ngpio >= 24) {
835 		chip->write_regs = pca953x_write_regs_24;
836 		chip->read_regs = pca953x_read_regs_24;
837 	} else {
838 		if (PCA_CHIP_TYPE(chip->driver_data) == PCA953X_TYPE)
839 			chip->write_regs = pca953x_write_regs_16;
840 		else
841 			chip->write_regs = pca957x_write_regs_16;
842 		chip->read_regs = pca953x_read_regs_16;
843 	}
844 
845 	if (PCA_CHIP_TYPE(chip->driver_data) == PCA953X_TYPE)
846 		ret = device_pca953x_init(chip, invert);
847 	else
848 		ret = device_pca957x_init(chip, invert);
849 	if (ret)
850 		goto err_exit;
851 
852 	ret = devm_gpiochip_add_data(&client->dev, &chip->gpio_chip, chip);
853 	if (ret)
854 		goto err_exit;
855 
856 	ret = pca953x_irq_setup(chip, irq_base);
857 	if (ret)
858 		goto err_exit;
859 
860 	if (pdata && pdata->setup) {
861 		ret = pdata->setup(client, chip->gpio_chip.base,
862 				chip->gpio_chip.ngpio, pdata->context);
863 		if (ret < 0)
864 			dev_warn(&client->dev, "setup failed, %d\n", ret);
865 	}
866 
867 	i2c_set_clientdata(client, chip);
868 	return 0;
869 
870 err_exit:
871 	regulator_disable(chip->regulator);
872 	return ret;
873 }
874 
875 static int pca953x_remove(struct i2c_client *client)
876 {
877 	struct pca953x_platform_data *pdata = dev_get_platdata(&client->dev);
878 	struct pca953x_chip *chip = i2c_get_clientdata(client);
879 	int ret;
880 
881 	if (pdata && pdata->teardown) {
882 		ret = pdata->teardown(client, chip->gpio_chip.base,
883 				chip->gpio_chip.ngpio, pdata->context);
884 		if (ret < 0)
885 			dev_err(&client->dev, "%s failed, %d\n",
886 					"teardown", ret);
887 	} else {
888 		ret = 0;
889 	}
890 
891 	regulator_disable(chip->regulator);
892 
893 	return ret;
894 }
895 
896 /* convenience to stop overlong match-table lines */
897 #define OF_953X(__nrgpio, __int) (void *)(__nrgpio | PCA953X_TYPE | __int)
898 #define OF_957X(__nrgpio, __int) (void *)(__nrgpio | PCA957X_TYPE | __int)
899 
900 static const struct of_device_id pca953x_dt_ids[] = {
901 	{ .compatible = "nxp,pca9505", .data = OF_953X(40, PCA_INT), },
902 	{ .compatible = "nxp,pca9534", .data = OF_953X( 8, PCA_INT), },
903 	{ .compatible = "nxp,pca9535", .data = OF_953X(16, PCA_INT), },
904 	{ .compatible = "nxp,pca9536", .data = OF_953X( 4, 0), },
905 	{ .compatible = "nxp,pca9537", .data = OF_953X( 4, PCA_INT), },
906 	{ .compatible = "nxp,pca9538", .data = OF_953X( 8, PCA_INT), },
907 	{ .compatible = "nxp,pca9539", .data = OF_953X(16, PCA_INT), },
908 	{ .compatible = "nxp,pca9554", .data = OF_953X( 8, PCA_INT), },
909 	{ .compatible = "nxp,pca9555", .data = OF_953X(16, PCA_INT), },
910 	{ .compatible = "nxp,pca9556", .data = OF_953X( 8, 0), },
911 	{ .compatible = "nxp,pca9557", .data = OF_953X( 8, 0), },
912 	{ .compatible = "nxp,pca9574", .data = OF_957X( 8, PCA_INT), },
913 	{ .compatible = "nxp,pca9575", .data = OF_957X(16, PCA_INT), },
914 	{ .compatible = "nxp,pca9698", .data = OF_953X(40, 0), },
915 
916 	{ .compatible = "maxim,max7310", .data = OF_953X( 8, 0), },
917 	{ .compatible = "maxim,max7312", .data = OF_953X(16, PCA_INT), },
918 	{ .compatible = "maxim,max7313", .data = OF_953X(16, PCA_INT), },
919 	{ .compatible = "maxim,max7315", .data = OF_953X( 8, PCA_INT), },
920 	{ .compatible = "maxim,max7318", .data = OF_953X(16, PCA_INT), },
921 
922 	{ .compatible = "ti,pca6107", .data = OF_953X( 8, PCA_INT), },
923 	{ .compatible = "ti,pca9536", .data = OF_953X( 4, 0), },
924 	{ .compatible = "ti,tca6408", .data = OF_953X( 8, PCA_INT), },
925 	{ .compatible = "ti,tca6416", .data = OF_953X(16, PCA_INT), },
926 	{ .compatible = "ti,tca6424", .data = OF_953X(24, PCA_INT), },
927 
928 	{ .compatible = "onsemi,pca9654", .data = OF_953X( 8, PCA_INT), },
929 
930 	{ .compatible = "exar,xra1202", .data = OF_953X( 8, 0), },
931 	{ }
932 };
933 
934 MODULE_DEVICE_TABLE(of, pca953x_dt_ids);
935 
936 static struct i2c_driver pca953x_driver = {
937 	.driver = {
938 		.name	= "pca953x",
939 		.of_match_table = pca953x_dt_ids,
940 		.acpi_match_table = ACPI_PTR(pca953x_acpi_ids),
941 	},
942 	.probe		= pca953x_probe,
943 	.remove		= pca953x_remove,
944 	.id_table	= pca953x_id,
945 };
946 
947 static int __init pca953x_init(void)
948 {
949 	return i2c_add_driver(&pca953x_driver);
950 }
951 /* register after i2c postcore initcall and before
952  * subsys initcalls that may rely on these GPIOs
953  */
954 subsys_initcall(pca953x_init);
955 
956 static void __exit pca953x_exit(void)
957 {
958 	i2c_del_driver(&pca953x_driver);
959 }
960 module_exit(pca953x_exit);
961 
962 MODULE_AUTHOR("eric miao <eric.miao@marvell.com>");
963 MODULE_DESCRIPTION("GPIO expander driver for PCA953x");
964 MODULE_LICENSE("GPL");
965