gpio-max732x.c 18.3 KB
Newer Older
Eric Miao's avatar
Eric Miao committed
1
/*
Grant Likely's avatar
Grant Likely committed
2
 *  MAX732x I2C Port Expander with 8/16 I/O
Eric Miao's avatar
Eric Miao committed
3 4 5 6
 *
 *  Copyright (C) 2007 Marvell International Ltd.
 *  Copyright (C) 2008 Jack Ren <jack.ren@marvell.com>
 *  Copyright (C) 2008 Eric Miao <eric.miao@marvell.com>
7
 *  Copyright (C) 2015 Linus Walleij <linus.walleij@linaro.org>
Eric Miao's avatar
Eric Miao committed
8 9 10 11 12 13 14 15 16 17 18 19
 *
 *  Derived from drivers/gpio/pca953x.c
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; version 2 of the License.
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/string.h>
20
#include <linux/gpio/driver.h>
21
#include <linux/interrupt.h>
Eric Miao's avatar
Eric Miao committed
22
#include <linux/i2c.h>
23
#include <linux/platform_data/max732x.h>
24
#include <linux/of.h>
Eric Miao's avatar
Eric Miao committed
25 26 27 28 29 30 31 32 33 34 35


/*
 * Each port of MAX732x (including MAX7319) falls into one of the
 * following three types:
 *
 *   - Push Pull Output
 *   - Input
 *   - Open Drain I/O
 *
 * designated by 'O', 'I' and 'P' individually according to MAXIM's
36 37
 * datasheets. 'I' and 'P' ports are interrupt capables, some with
 * a dedicated interrupt mask.
Eric Miao's avatar
Eric Miao committed
38 39 40 41 42 43 44 45 46 47 48 49
 *
 * There are two groups of I/O ports, each group usually includes
 * up to 8 I/O ports, and is accessed by a specific I2C address:
 *
 *   - Group A : by I2C address 0b'110xxxx
 *   - Group B : by I2C address 0b'101xxxx
 *
 * where 'xxxx' is decided by the connections of pin AD2/AD0.  The
 * address used also affects the initial state of output signals.
 *
 * Within each group of ports, there are five known combinations of
 * I/O ports: 4I4O, 4P4O, 8I, 8P, 8O, see the definitions below for
50 51
 * the detailed organization of these ports. Only Goup A is interrupt
 * capable.
Eric Miao's avatar
Eric Miao committed
52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74
 *
 * GPIO numbers start from 'gpio_base + 0' to 'gpio_base + 8/16',
 * and GPIOs from GROUP_A are numbered before those from GROUP_B
 * (if there are two groups).
 *
 * NOTE: MAX7328/MAX7329 are drop-in replacements for PCF8574/a, so
 * they are not supported by this driver.
 */

#define PORT_NONE	0x0	/* '/' No Port */
#define PORT_OUTPUT	0x1	/* 'O' Push-Pull, Output Only */
#define PORT_INPUT	0x2	/* 'I' Input Only */
#define PORT_OPENDRAIN	0x3	/* 'P' Open-Drain, I/O */

#define IO_4I4O		0x5AA5	/* O7 O6 I5 I4 I3 I2 O1 O0 */
#define IO_4P4O		0x5FF5	/* O7 O6 P5 P4 P3 P2 O1 O0 */
#define IO_8I		0xAAAA	/* I7 I6 I5 I4 I3 I2 I1 I0 */
#define IO_8P		0xFFFF	/* P7 P6 P5 P4 P3 P2 P1 P0 */
#define IO_8O		0x5555	/* O7 O6 O5 O4 O3 O2 O1 O0 */

#define GROUP_A(x)	((x) & 0xffff)	/* I2C Addr: 0b'110xxxx */
#define GROUP_B(x)	((x) << 16)	/* I2C Addr: 0b'101xxxx */

75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105
#define INT_NONE	0x0	/* No interrupt capability */
#define INT_NO_MASK	0x1	/* Has interrupts, no mask */
#define INT_INDEP_MASK	0x2	/* Has interrupts, independent mask */
#define INT_MERGED_MASK 0x3	/* Has interrupts, merged mask */

#define INT_CAPS(x)	(((uint64_t)(x)) << 32)

enum {
	MAX7319,
	MAX7320,
	MAX7321,
	MAX7322,
	MAX7323,
	MAX7324,
	MAX7325,
	MAX7326,
	MAX7327,
};

static uint64_t max732x_features[] = {
	[MAX7319] = GROUP_A(IO_8I) | INT_CAPS(INT_MERGED_MASK),
	[MAX7320] = GROUP_B(IO_8O),
	[MAX7321] = GROUP_A(IO_8P) | INT_CAPS(INT_NO_MASK),
	[MAX7322] = GROUP_A(IO_4I4O) | INT_CAPS(INT_MERGED_MASK),
	[MAX7323] = GROUP_A(IO_4P4O) | INT_CAPS(INT_INDEP_MASK),
	[MAX7324] = GROUP_A(IO_8I) | GROUP_B(IO_8O) | INT_CAPS(INT_MERGED_MASK),
	[MAX7325] = GROUP_A(IO_8P) | GROUP_B(IO_8O) | INT_CAPS(INT_NO_MASK),
	[MAX7326] = GROUP_A(IO_4I4O) | GROUP_B(IO_8O) | INT_CAPS(INT_MERGED_MASK),
	[MAX7327] = GROUP_A(IO_4P4O) | GROUP_B(IO_8O) | INT_CAPS(INT_NO_MASK),
};

Eric Miao's avatar
Eric Miao committed
106
static const struct i2c_device_id max732x_id[] = {
107 108 109 110 111 112 113 114 115
	{ "max7319", MAX7319 },
	{ "max7320", MAX7320 },
	{ "max7321", MAX7321 },
	{ "max7322", MAX7322 },
	{ "max7323", MAX7323 },
	{ "max7324", MAX7324 },
	{ "max7325", MAX7325 },
	{ "max7326", MAX7326 },
	{ "max7327", MAX7327 },
Eric Miao's avatar
Eric Miao committed
116 117 118 119
	{ },
};
MODULE_DEVICE_TABLE(i2c, max732x_id);

120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135
#ifdef CONFIG_OF
static const struct of_device_id max732x_of_table[] = {
	{ .compatible = "maxim,max7319" },
	{ .compatible = "maxim,max7320" },
	{ .compatible = "maxim,max7321" },
	{ .compatible = "maxim,max7322" },
	{ .compatible = "maxim,max7323" },
	{ .compatible = "maxim,max7324" },
	{ .compatible = "maxim,max7325" },
	{ .compatible = "maxim,max7326" },
	{ .compatible = "maxim,max7327" },
	{ }
};
MODULE_DEVICE_TABLE(of, max732x_of_table);
#endif

Eric Miao's avatar
Eric Miao committed
136 137 138 139 140 141 142 143 144 145 146 147 148 149
struct max732x_chip {
	struct gpio_chip gpio_chip;

	struct i2c_client *client;	/* "main" client */
	struct i2c_client *client_dummy;
	struct i2c_client *client_group_a;
	struct i2c_client *client_group_b;

	unsigned int	mask_group_a;
	unsigned int	dir_input;
	unsigned int	dir_output;

	struct mutex	lock;
	uint8_t		reg_out[2];
150 151

#ifdef CONFIG_GPIO_MAX732X_IRQ
152 153 154 155 156 157
	struct mutex		irq_lock;
	uint8_t			irq_mask;
	uint8_t			irq_mask_cur;
	uint8_t			irq_trig_raise;
	uint8_t			irq_trig_fall;
	uint8_t			irq_features;
158
#endif
Eric Miao's avatar
Eric Miao committed
159 160
};

161
static int max732x_writeb(struct max732x_chip *chip, int group_a, uint8_t val)
Eric Miao's avatar
Eric Miao committed
162 163 164 165 166 167 168 169 170 171 172 173 174 175
{
	struct i2c_client *client;
	int ret;

	client = group_a ? chip->client_group_a : chip->client_group_b;
	ret = i2c_smbus_write_byte(client, val);
	if (ret < 0) {
		dev_err(&client->dev, "failed writing\n");
		return ret;
	}

	return 0;
}

176
static int max732x_readb(struct max732x_chip *chip, int group_a, uint8_t *val)
Eric Miao's avatar
Eric Miao committed
177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198
{
	struct i2c_client *client;
	int ret;

	client = group_a ? chip->client_group_a : chip->client_group_b;
	ret = i2c_smbus_read_byte(client);
	if (ret < 0) {
		dev_err(&client->dev, "failed reading\n");
		return ret;
	}

	*val = (uint8_t)ret;
	return 0;
}

static inline int is_group_a(struct max732x_chip *chip, unsigned off)
{
	return (1u << off) & chip->mask_group_a;
}

static int max732x_gpio_get_value(struct gpio_chip *gc, unsigned off)
{
199
	struct max732x_chip *chip = gpiochip_get_data(gc);
Eric Miao's avatar
Eric Miao committed
200 201 202
	uint8_t reg_val;
	int ret;

203
	ret = max732x_readb(chip, is_group_a(chip, off), &reg_val);
Eric Miao's avatar
Eric Miao committed
204
	if (ret < 0)
205
		return ret;
Eric Miao's avatar
Eric Miao committed
206

207
	return !!(reg_val & (1u << (off & 0x7)));
Eric Miao's avatar
Eric Miao committed
208 209
}

210 211
static void max732x_gpio_set_mask(struct gpio_chip *gc, unsigned off, int mask,
				  int val)
Eric Miao's avatar
Eric Miao committed
212
{
213
	struct max732x_chip *chip = gpiochip_get_data(gc);
214
	uint8_t reg_out;
Eric Miao's avatar
Eric Miao committed
215 216 217 218 219
	int ret;

	mutex_lock(&chip->lock);

	reg_out = (off > 7) ? chip->reg_out[1] : chip->reg_out[0];
220
	reg_out = (reg_out & ~mask) | (val & mask);
Eric Miao's avatar
Eric Miao committed
221

222
	ret = max732x_writeb(chip, is_group_a(chip, off), reg_out);
Eric Miao's avatar
Eric Miao committed
223 224 225 226 227 228 229 230 231 232 233 234
	if (ret < 0)
		goto out;

	/* update the shadow register then */
	if (off > 7)
		chip->reg_out[1] = reg_out;
	else
		chip->reg_out[0] = reg_out;
out:
	mutex_unlock(&chip->lock);
}

235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254
static void max732x_gpio_set_value(struct gpio_chip *gc, unsigned off, int val)
{
	unsigned base = off & ~0x7;
	uint8_t mask = 1u << (off & 0x7);

	max732x_gpio_set_mask(gc, base, mask, val << (off & 0x7));
}

static void max732x_gpio_set_multiple(struct gpio_chip *gc,
				      unsigned long *mask, unsigned long *bits)
{
	unsigned mask_lo = mask[0] & 0xff;
	unsigned mask_hi = (mask[0] >> 8) & 0xff;

	if (mask_lo)
		max732x_gpio_set_mask(gc, 0, mask_lo, bits[0] & 0xff);
	if (mask_hi)
		max732x_gpio_set_mask(gc, 8, mask_hi, (bits[0] >> 8) & 0xff);
}

Eric Miao's avatar
Eric Miao committed
255 256
static int max732x_gpio_direction_input(struct gpio_chip *gc, unsigned off)
{
257
	struct max732x_chip *chip = gpiochip_get_data(gc);
Eric Miao's avatar
Eric Miao committed
258 259 260 261 262 263 264 265
	unsigned int mask = 1u << off;

	if ((mask & chip->dir_input) == 0) {
		dev_dbg(&chip->client->dev, "%s port %d is output only\n",
			chip->client->name, off);
		return -EACCES;
	}

266 267 268 269 270 271 272
	/*
	 * Open-drain pins must be set to high impedance (which is
	 * equivalent to output-high) to be turned into an input.
	 */
	if ((mask & chip->dir_output))
		max732x_gpio_set_value(gc, off, 1);

Eric Miao's avatar
Eric Miao committed
273 274 275 276 277 278
	return 0;
}

static int max732x_gpio_direction_output(struct gpio_chip *gc,
		unsigned off, int val)
{
279
	struct max732x_chip *chip = gpiochip_get_data(gc);
Eric Miao's avatar
Eric Miao committed
280 281 282 283 284 285 286 287 288 289 290 291
	unsigned int mask = 1u << off;

	if ((mask & chip->dir_output) == 0) {
		dev_dbg(&chip->client->dev, "%s port %d is input only\n",
			chip->client->name, off);
		return -EACCES;
	}

	max732x_gpio_set_value(gc, off, val);
	return 0;
}

292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350
#ifdef CONFIG_GPIO_MAX732X_IRQ
static int max732x_writew(struct max732x_chip *chip, uint16_t val)
{
	int ret;

	val = cpu_to_le16(val);

	ret = i2c_master_send(chip->client_group_a, (char *)&val, 2);
	if (ret < 0) {
		dev_err(&chip->client_group_a->dev, "failed writing\n");
		return ret;
	}

	return 0;
}

static int max732x_readw(struct max732x_chip *chip, uint16_t *val)
{
	int ret;

	ret = i2c_master_recv(chip->client_group_a, (char *)val, 2);
	if (ret < 0) {
		dev_err(&chip->client_group_a->dev, "failed reading\n");
		return ret;
	}

	*val = le16_to_cpu(*val);
	return 0;
}

static void max732x_irq_update_mask(struct max732x_chip *chip)
{
	uint16_t msg;

	if (chip->irq_mask == chip->irq_mask_cur)
		return;

	chip->irq_mask = chip->irq_mask_cur;

	if (chip->irq_features == INT_NO_MASK)
		return;

	mutex_lock(&chip->lock);

	switch (chip->irq_features) {
	case INT_INDEP_MASK:
		msg = (chip->irq_mask << 8) | chip->reg_out[0];
		max732x_writew(chip, msg);
		break;

	case INT_MERGED_MASK:
		msg = chip->irq_mask | chip->reg_out[0];
		max732x_writeb(chip, 1, (uint8_t)msg);
		break;
	}

	mutex_unlock(&chip->lock);
}

351
static void max732x_irq_mask(struct irq_data *d)
352
{
353
	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
354
	struct max732x_chip *chip = gpiochip_get_data(gc);
355

356
	chip->irq_mask_cur &= ~(1 << d->hwirq);
357 358
}

359
static void max732x_irq_unmask(struct irq_data *d)
360
{
361
	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
362
	struct max732x_chip *chip = gpiochip_get_data(gc);
363

364
	chip->irq_mask_cur |= 1 << d->hwirq;
365 366
}

367
static void max732x_irq_bus_lock(struct irq_data *d)
368
{
369
	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
370
	struct max732x_chip *chip = gpiochip_get_data(gc);
371 372 373 374 375

	mutex_lock(&chip->irq_lock);
	chip->irq_mask_cur = chip->irq_mask;
}

376
static void max732x_irq_bus_sync_unlock(struct irq_data *d)
377
{
378
	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
379
	struct max732x_chip *chip = gpiochip_get_data(gc);
380 381
	uint16_t new_irqs;
	uint16_t level;
382 383

	max732x_irq_update_mask(chip);
384 385 386 387 388 389 390 391

	new_irqs = chip->irq_trig_fall | chip->irq_trig_raise;
	while (new_irqs) {
		level = __ffs(new_irqs);
		max732x_gpio_direction_input(&chip->gpio_chip, level);
		new_irqs &= ~(1 << level);
	}

392 393 394
	mutex_unlock(&chip->irq_lock);
}

395
static int max732x_irq_set_type(struct irq_data *d, unsigned int type)
396
{
397
	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
398
	struct max732x_chip *chip = gpiochip_get_data(gc);
399
	uint16_t off = d->hwirq;
400 401 402 403 404 405 406 407 408 409
	uint16_t mask = 1 << off;

	if (!(mask & chip->dir_input)) {
		dev_dbg(&chip->client->dev, "%s port %d is output only\n",
			chip->client->name, off);
		return -EACCES;
	}

	if (!(type & IRQ_TYPE_EDGE_BOTH)) {
		dev_err(&chip->client->dev, "irq %d: unsupported type %d\n",
410
			d->irq, type);
411 412 413 414 415 416 417 418 419 420 421 422 423
		return -EINVAL;
	}

	if (type & IRQ_TYPE_EDGE_FALLING)
		chip->irq_trig_fall |= mask;
	else
		chip->irq_trig_fall &= ~mask;

	if (type & IRQ_TYPE_EDGE_RISING)
		chip->irq_trig_raise |= mask;
	else
		chip->irq_trig_raise &= ~mask;

424
	return 0;
425 426
}

427 428 429 430 431 432 433 434
static int max732x_irq_set_wake(struct irq_data *data, unsigned int on)
{
	struct max732x_chip *chip = irq_data_get_irq_chip_data(data);

	irq_set_irq_wake(chip->client->irq, on);
	return 0;
}

435 436
static struct irq_chip max732x_irq_chip = {
	.name			= "max732x",
437 438 439 440 441
	.irq_mask		= max732x_irq_mask,
	.irq_unmask		= max732x_irq_unmask,
	.irq_bus_lock		= max732x_irq_bus_lock,
	.irq_bus_sync_unlock	= max732x_irq_bus_sync_unlock,
	.irq_set_type		= max732x_irq_set_type,
442
	.irq_set_wake		= max732x_irq_set_wake,
443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488
};

static uint8_t max732x_irq_pending(struct max732x_chip *chip)
{
	uint8_t cur_stat;
	uint8_t old_stat;
	uint8_t trigger;
	uint8_t pending;
	uint16_t status;
	int ret;

	ret = max732x_readw(chip, &status);
	if (ret)
		return 0;

	trigger = status >> 8;
	trigger &= chip->irq_mask;

	if (!trigger)
		return 0;

	cur_stat = status & 0xFF;
	cur_stat &= chip->irq_mask;

	old_stat = cur_stat ^ trigger;

	pending = (old_stat & chip->irq_trig_fall) |
		  (cur_stat & chip->irq_trig_raise);
	pending &= trigger;

	return pending;
}

static irqreturn_t max732x_irq_handler(int irq, void *devid)
{
	struct max732x_chip *chip = devid;
	uint8_t pending;
	uint8_t level;

	pending = max732x_irq_pending(chip);

	if (!pending)
		return IRQ_HANDLED;

	do {
		level = __ffs(pending);
489
		handle_nested_irq(irq_find_mapping(chip->gpio_chip.irq.domain,
490
						   level));
491 492 493 494 495 496 497 498 499 500 501

		pending &= ~(1 << level);
	} while (pending);

	return IRQ_HANDLED;
}

static int max732x_irq_setup(struct max732x_chip *chip,
			     const struct i2c_device_id *id)
{
	struct i2c_client *client = chip->client;
502
	struct max732x_platform_data *pdata = dev_get_platdata(&client->dev);
503
	int has_irq = max732x_features[id->driver_data] >> 32;
504
	int irq_base = 0;
505 506
	int ret;

507 508 509
	if (((pdata && pdata->irq_base) || client->irq)
			&& has_irq != INT_NONE) {
		if (pdata)
510
			irq_base = pdata->irq_base;
511 512 513
		chip->irq_features = has_irq;
		mutex_init(&chip->irq_lock);

514 515 516 517
		ret = devm_request_threaded_irq(&client->dev, client->irq,
				NULL, max732x_irq_handler, IRQF_ONESHOT |
				IRQF_TRIGGER_FALLING | IRQF_SHARED,
				dev_name(&client->dev), chip);
518 519 520
		if (ret) {
			dev_err(&client->dev, "failed to request irq %d\n",
				client->irq);
521
			return ret;
522
		}
523 524 525 526 527
		ret =  gpiochip_irqchip_add_nested(&chip->gpio_chip,
						   &max732x_irq_chip,
						   irq_base,
						   handle_simple_irq,
						   IRQ_TYPE_NONE);
528 529 530 531 532
		if (ret) {
			dev_err(&client->dev,
				"could not connect irqchip to gpiochip\n");
			return ret;
		}
533 534 535
		gpiochip_set_nested_irqchip(&chip->gpio_chip,
					    &max732x_irq_chip,
					    client->irq);
536 537 538 539 540 541 542 543 544 545
	}

	return 0;
}

#else /* CONFIG_GPIO_MAX732X_IRQ */
static int max732x_irq_setup(struct max732x_chip *chip,
			     const struct i2c_device_id *id)
{
	struct i2c_client *client = chip->client;
546
	struct max732x_platform_data *pdata = dev_get_platdata(&client->dev);
547 548
	int has_irq = max732x_features[id->driver_data] >> 32;

549
	if (((pdata && pdata->irq_base) || client->irq) && has_irq != INT_NONE)
550 551 552 553 554 555
		dev_warn(&client->dev, "interrupt support not compiled in\n");

	return 0;
}
#endif

556
static int max732x_setup_gpio(struct max732x_chip *chip,
Eric Miao's avatar
Eric Miao committed
557 558 559 560
					const struct i2c_device_id *id,
					unsigned gpio_start)
{
	struct gpio_chip *gc = &chip->gpio_chip;
561
	uint32_t id_data = (uint32_t)max732x_features[id->driver_data];
Eric Miao's avatar
Eric Miao committed
562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591
	int i, port = 0;

	for (i = 0; i < 16; i++, id_data >>= 2) {
		unsigned int mask = 1 << port;

		switch (id_data & 0x3) {
		case PORT_OUTPUT:
			chip->dir_output |= mask;
			break;
		case PORT_INPUT:
			chip->dir_input |= mask;
			break;
		case PORT_OPENDRAIN:
			chip->dir_output |= mask;
			chip->dir_input |= mask;
			break;
		default:
			continue;
		}

		if (i < 8)
			chip->mask_group_a |= mask;
		port++;
	}

	if (chip->dir_input)
		gc->direction_input = max732x_gpio_direction_input;
	if (chip->dir_output) {
		gc->direction_output = max732x_gpio_direction_output;
		gc->set = max732x_gpio_set_value;
592
		gc->set_multiple = max732x_gpio_set_multiple;
Eric Miao's avatar
Eric Miao committed
593 594
	}
	gc->get = max732x_gpio_get_value;
595
	gc->can_sleep = true;
Eric Miao's avatar
Eric Miao committed
596 597 598 599

	gc->base = gpio_start;
	gc->ngpio = port;
	gc->label = chip->client->name;
600
	gc->parent = &chip->client->dev;
Eric Miao's avatar
Eric Miao committed
601 602 603 604 605
	gc->owner = THIS_MODULE;

	return port;
}

606 607 608 609 610 611 612 613 614 615 616 617 618
static struct max732x_platform_data *of_gpio_max732x(struct device *dev)
{
	struct max732x_platform_data *pdata;

	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
	if (!pdata)
		return NULL;

	pdata->gpio_base = -1;

	return pdata;
}

619
static int max732x_probe(struct i2c_client *client,
Eric Miao's avatar
Eric Miao committed
620 621 622
				   const struct i2c_device_id *id)
{
	struct max732x_platform_data *pdata;
623
	struct device_node *node;
Eric Miao's avatar
Eric Miao committed
624 625 626 627 628
	struct max732x_chip *chip;
	struct i2c_client *c;
	uint16_t addr_a, addr_b;
	int ret, nr_port;

629
	pdata = dev_get_platdata(&client->dev);
630 631 632 633 634 635
	node = client->dev.of_node;

	if (!pdata && node)
		pdata = of_gpio_max732x(&client->dev);

	if (!pdata) {
636 637 638
		dev_dbg(&client->dev, "no platform data\n");
		return -EINVAL;
	}
Eric Miao's avatar
Eric Miao committed
639

640
	chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
Eric Miao's avatar
Eric Miao committed
641 642 643 644 645
	if (chip == NULL)
		return -ENOMEM;
	chip->client = client;

	nr_port = max732x_setup_gpio(chip, id, pdata->gpio_base);
646
	chip->gpio_chip.parent = &client->dev;
Eric Miao's avatar
Eric Miao committed
647 648 649 650 651 652 653

	addr_a = (client->addr & 0x0f) | 0x60;
	addr_b = (client->addr & 0x0f) | 0x50;

	switch (client->addr & 0x70) {
	case 0x60:
		chip->client_group_a = client;
654
		if (nr_port > 8) {
Eric Miao's avatar
Eric Miao committed
655 656 657 658 659 660
			c = i2c_new_dummy(client->adapter, addr_b);
			chip->client_group_b = chip->client_dummy = c;
		}
		break;
	case 0x50:
		chip->client_group_b = client;
661
		if (nr_port > 8) {
Eric Miao's avatar
Eric Miao committed
662 663 664 665 666 667 668 669 670
			c = i2c_new_dummy(client->adapter, addr_a);
			chip->client_group_a = chip->client_dummy = c;
		}
		break;
	default:
		dev_err(&client->dev, "invalid I2C address specified %02x\n",
				client->addr);
		ret = -EINVAL;
		goto out_failed;
671 672 673 674 675 676 677
	}

	if (nr_port > 8 && !chip->client_dummy) {
		dev_err(&client->dev,
			"Failed to allocate second group I2C device\n");
		ret = -ENODEV;
		goto out_failed;
Eric Miao's avatar
Eric Miao committed
678 679 680 681
	}

	mutex_init(&chip->lock);

682 683 684 685 686 687 688 689
	ret = max732x_readb(chip, is_group_a(chip, 0), &chip->reg_out[0]);
	if (ret)
		goto out_failed;
	if (nr_port > 8) {
		ret = max732x_readb(chip, is_group_a(chip, 8), &chip->reg_out[1]);
		if (ret)
			goto out_failed;
	}
690

691
	ret = gpiochip_add_data(&chip->gpio_chip, chip);
692 693
	if (ret)
		goto out_failed;
Eric Miao's avatar
Eric Miao committed
694

695 696 697
	ret = max732x_irq_setup(chip, id);
	if (ret) {
		gpiochip_remove(&chip->gpio_chip);
Eric Miao's avatar
Eric Miao committed
698
		goto out_failed;
699
	}
Eric Miao's avatar
Eric Miao committed
700

701
	if (pdata && pdata->setup) {
Eric Miao's avatar
Eric Miao committed
702 703 704 705 706 707 708 709 710 711
		ret = pdata->setup(client, chip->gpio_chip.base,
				chip->gpio_chip.ngpio, pdata->context);
		if (ret < 0)
			dev_warn(&client->dev, "setup failed, %d\n", ret);
	}

	i2c_set_clientdata(client, chip);
	return 0;

out_failed:
712 713
	if (chip->client_dummy)
		i2c_unregister_device(chip->client_dummy);
Eric Miao's avatar
Eric Miao committed
714 715 716
	return ret;
}

717
static int max732x_remove(struct i2c_client *client)
Eric Miao's avatar
Eric Miao committed
718
{
719
	struct max732x_platform_data *pdata = dev_get_platdata(&client->dev);
Eric Miao's avatar
Eric Miao committed
720 721
	struct max732x_chip *chip = i2c_get_clientdata(client);

722 723 724
	if (pdata && pdata->teardown) {
		int ret;

Eric Miao's avatar
Eric Miao committed
725 726 727 728 729 730 731 732 733
		ret = pdata->teardown(client, chip->gpio_chip.base,
				chip->gpio_chip.ngpio, pdata->context);
		if (ret < 0) {
			dev_err(&client->dev, "%s failed, %d\n",
					"teardown", ret);
			return ret;
		}
	}

734
	gpiochip_remove(&chip->gpio_chip);
Eric Miao's avatar
Eric Miao committed
735 736 737 738 739 740 741 742 743 744

	/* unregister any dummy i2c_client */
	if (chip->client_dummy)
		i2c_unregister_device(chip->client_dummy);

	return 0;
}

static struct i2c_driver max732x_driver = {
	.driver = {
745 746
		.name		= "max732x",
		.of_match_table	= of_match_ptr(max732x_of_table),
Eric Miao's avatar
Eric Miao committed
747 748
	},
	.probe		= max732x_probe,
749
	.remove		= max732x_remove,
Eric Miao's avatar
Eric Miao committed
750 751 752 753 754 755 756
	.id_table	= max732x_id,
};

static int __init max732x_init(void)
{
	return i2c_add_driver(&max732x_driver);
}
757 758 759 760
/* register after i2c postcore initcall and before
 * subsys initcalls that may rely on these GPIOs
 */
subsys_initcall(max732x_init);
Eric Miao's avatar
Eric Miao committed
761 762 763 764 765 766 767 768 769 770

static void __exit max732x_exit(void)
{
	i2c_del_driver(&max732x_driver);
}
module_exit(max732x_exit);

MODULE_AUTHOR("Eric Miao <eric.miao@marvell.com>");
MODULE_DESCRIPTION("GPIO expander driver for MAX732X");
MODULE_LICENSE("GPL");