1 /* 2 * MAX732x I2C Port Expander with 8/16 I/O 3 * 4 * Copyright (C) 2007 Marvell International Ltd. 5 * Copyright (C) 2008 Jack Ren <jack.ren@marvell.com> 6 * Copyright (C) 2008 Eric Miao <eric.miao@marvell.com> 7 * Copyright (C) 2015 Linus Walleij <linus.walleij@linaro.org> 8 * 9 * Derived from drivers/gpio/pca953x.c 10 * 11 * This program is free software; you can redistribute it and/or modify 12 * it under the terms of the GNU General Public License as published by 13 * the Free Software Foundation; version 2 of the License. 14 */ 15 16 #include <linux/module.h> 17 #include <linux/init.h> 18 #include <linux/slab.h> 19 #include <linux/string.h> 20 #include <linux/gpio/driver.h> 21 #include <linux/interrupt.h> 22 #include <linux/i2c.h> 23 #include <linux/platform_data/max732x.h> 24 #include <linux/of.h> 25 26 27 /* 28 * Each port of MAX732x (including MAX7319) falls into one of the 29 * following three types: 30 * 31 * - Push Pull Output 32 * - Input 33 * - Open Drain I/O 34 * 35 * designated by 'O', 'I' and 'P' individually according to MAXIM's 36 * datasheets. 'I' and 'P' ports are interrupt capables, some with 37 * a dedicated interrupt mask. 38 * 39 * There are two groups of I/O ports, each group usually includes 40 * up to 8 I/O ports, and is accessed by a specific I2C address: 41 * 42 * - Group A : by I2C address 0b'110xxxx 43 * - Group B : by I2C address 0b'101xxxx 44 * 45 * where 'xxxx' is decided by the connections of pin AD2/AD0. The 46 * address used also affects the initial state of output signals. 47 * 48 * Within each group of ports, there are five known combinations of 49 * I/O ports: 4I4O, 4P4O, 8I, 8P, 8O, see the definitions below for 50 * the detailed organization of these ports. Only Goup A is interrupt 51 * capable. 52 * 53 * GPIO numbers start from 'gpio_base + 0' to 'gpio_base + 8/16', 54 * and GPIOs from GROUP_A are numbered before those from GROUP_B 55 * (if there are two groups). 56 * 57 * NOTE: MAX7328/MAX7329 are drop-in replacements for PCF8574/a, so 58 * they are not supported by this driver. 59 */ 60 61 #define PORT_NONE 0x0 /* '/' No Port */ 62 #define PORT_OUTPUT 0x1 /* 'O' Push-Pull, Output Only */ 63 #define PORT_INPUT 0x2 /* 'I' Input Only */ 64 #define PORT_OPENDRAIN 0x3 /* 'P' Open-Drain, I/O */ 65 66 #define IO_4I4O 0x5AA5 /* O7 O6 I5 I4 I3 I2 O1 O0 */ 67 #define IO_4P4O 0x5FF5 /* O7 O6 P5 P4 P3 P2 O1 O0 */ 68 #define IO_8I 0xAAAA /* I7 I6 I5 I4 I3 I2 I1 I0 */ 69 #define IO_8P 0xFFFF /* P7 P6 P5 P4 P3 P2 P1 P0 */ 70 #define IO_8O 0x5555 /* O7 O6 O5 O4 O3 O2 O1 O0 */ 71 72 #define GROUP_A(x) ((x) & 0xffff) /* I2C Addr: 0b'110xxxx */ 73 #define GROUP_B(x) ((x) << 16) /* I2C Addr: 0b'101xxxx */ 74 75 #define INT_NONE 0x0 /* No interrupt capability */ 76 #define INT_NO_MASK 0x1 /* Has interrupts, no mask */ 77 #define INT_INDEP_MASK 0x2 /* Has interrupts, independent mask */ 78 #define INT_MERGED_MASK 0x3 /* Has interrupts, merged mask */ 79 80 #define INT_CAPS(x) (((uint64_t)(x)) << 32) 81 82 enum { 83 MAX7319, 84 MAX7320, 85 MAX7321, 86 MAX7322, 87 MAX7323, 88 MAX7324, 89 MAX7325, 90 MAX7326, 91 MAX7327, 92 }; 93 94 static uint64_t max732x_features[] = { 95 [MAX7319] = GROUP_A(IO_8I) | INT_CAPS(INT_MERGED_MASK), 96 [MAX7320] = GROUP_B(IO_8O), 97 [MAX7321] = GROUP_A(IO_8P) | INT_CAPS(INT_NO_MASK), 98 [MAX7322] = GROUP_A(IO_4I4O) | INT_CAPS(INT_MERGED_MASK), 99 [MAX7323] = GROUP_A(IO_4P4O) | INT_CAPS(INT_INDEP_MASK), 100 [MAX7324] = GROUP_A(IO_8I) | GROUP_B(IO_8O) | INT_CAPS(INT_MERGED_MASK), 101 [MAX7325] = GROUP_A(IO_8P) | GROUP_B(IO_8O) | INT_CAPS(INT_NO_MASK), 102 [MAX7326] = GROUP_A(IO_4I4O) | GROUP_B(IO_8O) | INT_CAPS(INT_MERGED_MASK), 103 [MAX7327] = GROUP_A(IO_4P4O) | GROUP_B(IO_8O) | INT_CAPS(INT_NO_MASK), 104 }; 105 106 static const struct i2c_device_id max732x_id[] = { 107 { "max7319", MAX7319 }, 108 { "max7320", MAX7320 }, 109 { "max7321", MAX7321 }, 110 { "max7322", MAX7322 }, 111 { "max7323", MAX7323 }, 112 { "max7324", MAX7324 }, 113 { "max7325", MAX7325 }, 114 { "max7326", MAX7326 }, 115 { "max7327", MAX7327 }, 116 { }, 117 }; 118 MODULE_DEVICE_TABLE(i2c, max732x_id); 119 120 #ifdef CONFIG_OF 121 static const struct of_device_id max732x_of_table[] = { 122 { .compatible = "maxim,max7319" }, 123 { .compatible = "maxim,max7320" }, 124 { .compatible = "maxim,max7321" }, 125 { .compatible = "maxim,max7322" }, 126 { .compatible = "maxim,max7323" }, 127 { .compatible = "maxim,max7324" }, 128 { .compatible = "maxim,max7325" }, 129 { .compatible = "maxim,max7326" }, 130 { .compatible = "maxim,max7327" }, 131 { } 132 }; 133 MODULE_DEVICE_TABLE(of, max732x_of_table); 134 #endif 135 136 struct max732x_chip { 137 struct gpio_chip gpio_chip; 138 139 struct i2c_client *client; /* "main" client */ 140 struct i2c_client *client_dummy; 141 struct i2c_client *client_group_a; 142 struct i2c_client *client_group_b; 143 144 unsigned int mask_group_a; 145 unsigned int dir_input; 146 unsigned int dir_output; 147 148 struct mutex lock; 149 uint8_t reg_out[2]; 150 151 #ifdef CONFIG_GPIO_MAX732X_IRQ 152 struct mutex irq_lock; 153 uint8_t irq_mask; 154 uint8_t irq_mask_cur; 155 uint8_t irq_trig_raise; 156 uint8_t irq_trig_fall; 157 uint8_t irq_features; 158 #endif 159 }; 160 161 static int max732x_writeb(struct max732x_chip *chip, int group_a, uint8_t val) 162 { 163 struct i2c_client *client; 164 int ret; 165 166 client = group_a ? chip->client_group_a : chip->client_group_b; 167 ret = i2c_smbus_write_byte(client, val); 168 if (ret < 0) { 169 dev_err(&client->dev, "failed writing\n"); 170 return ret; 171 } 172 173 return 0; 174 } 175 176 static int max732x_readb(struct max732x_chip *chip, int group_a, uint8_t *val) 177 { 178 struct i2c_client *client; 179 int ret; 180 181 client = group_a ? chip->client_group_a : chip->client_group_b; 182 ret = i2c_smbus_read_byte(client); 183 if (ret < 0) { 184 dev_err(&client->dev, "failed reading\n"); 185 return ret; 186 } 187 188 *val = (uint8_t)ret; 189 return 0; 190 } 191 192 static inline int is_group_a(struct max732x_chip *chip, unsigned off) 193 { 194 return (1u << off) & chip->mask_group_a; 195 } 196 197 static int max732x_gpio_get_value(struct gpio_chip *gc, unsigned off) 198 { 199 struct max732x_chip *chip = gpiochip_get_data(gc); 200 uint8_t reg_val; 201 int ret; 202 203 ret = max732x_readb(chip, is_group_a(chip, off), ®_val); 204 if (ret < 0) 205 return ret; 206 207 return !!(reg_val & (1u << (off & 0x7))); 208 } 209 210 static void max732x_gpio_set_mask(struct gpio_chip *gc, unsigned off, int mask, 211 int val) 212 { 213 struct max732x_chip *chip = gpiochip_get_data(gc); 214 uint8_t reg_out; 215 int ret; 216 217 mutex_lock(&chip->lock); 218 219 reg_out = (off > 7) ? chip->reg_out[1] : chip->reg_out[0]; 220 reg_out = (reg_out & ~mask) | (val & mask); 221 222 ret = max732x_writeb(chip, is_group_a(chip, off), reg_out); 223 if (ret < 0) 224 goto out; 225 226 /* update the shadow register then */ 227 if (off > 7) 228 chip->reg_out[1] = reg_out; 229 else 230 chip->reg_out[0] = reg_out; 231 out: 232 mutex_unlock(&chip->lock); 233 } 234 235 static void max732x_gpio_set_value(struct gpio_chip *gc, unsigned off, int val) 236 { 237 unsigned base = off & ~0x7; 238 uint8_t mask = 1u << (off & 0x7); 239 240 max732x_gpio_set_mask(gc, base, mask, val << (off & 0x7)); 241 } 242 243 static void max732x_gpio_set_multiple(struct gpio_chip *gc, 244 unsigned long *mask, unsigned long *bits) 245 { 246 unsigned mask_lo = mask[0] & 0xff; 247 unsigned mask_hi = (mask[0] >> 8) & 0xff; 248 249 if (mask_lo) 250 max732x_gpio_set_mask(gc, 0, mask_lo, bits[0] & 0xff); 251 if (mask_hi) 252 max732x_gpio_set_mask(gc, 8, mask_hi, (bits[0] >> 8) & 0xff); 253 } 254 255 static int max732x_gpio_direction_input(struct gpio_chip *gc, unsigned off) 256 { 257 struct max732x_chip *chip = gpiochip_get_data(gc); 258 unsigned int mask = 1u << off; 259 260 if ((mask & chip->dir_input) == 0) { 261 dev_dbg(&chip->client->dev, "%s port %d is output only\n", 262 chip->client->name, off); 263 return -EACCES; 264 } 265 266 /* 267 * Open-drain pins must be set to high impedance (which is 268 * equivalent to output-high) to be turned into an input. 269 */ 270 if ((mask & chip->dir_output)) 271 max732x_gpio_set_value(gc, off, 1); 272 273 return 0; 274 } 275 276 static int max732x_gpio_direction_output(struct gpio_chip *gc, 277 unsigned off, int val) 278 { 279 struct max732x_chip *chip = gpiochip_get_data(gc); 280 unsigned int mask = 1u << off; 281 282 if ((mask & chip->dir_output) == 0) { 283 dev_dbg(&chip->client->dev, "%s port %d is input only\n", 284 chip->client->name, off); 285 return -EACCES; 286 } 287 288 max732x_gpio_set_value(gc, off, val); 289 return 0; 290 } 291 292 #ifdef CONFIG_GPIO_MAX732X_IRQ 293 static int max732x_writew(struct max732x_chip *chip, uint16_t val) 294 { 295 int ret; 296 297 val = cpu_to_le16(val); 298 299 ret = i2c_master_send(chip->client_group_a, (char *)&val, 2); 300 if (ret < 0) { 301 dev_err(&chip->client_group_a->dev, "failed writing\n"); 302 return ret; 303 } 304 305 return 0; 306 } 307 308 static int max732x_readw(struct max732x_chip *chip, uint16_t *val) 309 { 310 int ret; 311 312 ret = i2c_master_recv(chip->client_group_a, (char *)val, 2); 313 if (ret < 0) { 314 dev_err(&chip->client_group_a->dev, "failed reading\n"); 315 return ret; 316 } 317 318 *val = le16_to_cpu(*val); 319 return 0; 320 } 321 322 static void max732x_irq_update_mask(struct max732x_chip *chip) 323 { 324 uint16_t msg; 325 326 if (chip->irq_mask == chip->irq_mask_cur) 327 return; 328 329 chip->irq_mask = chip->irq_mask_cur; 330 331 if (chip->irq_features == INT_NO_MASK) 332 return; 333 334 mutex_lock(&chip->lock); 335 336 switch (chip->irq_features) { 337 case INT_INDEP_MASK: 338 msg = (chip->irq_mask << 8) | chip->reg_out[0]; 339 max732x_writew(chip, msg); 340 break; 341 342 case INT_MERGED_MASK: 343 msg = chip->irq_mask | chip->reg_out[0]; 344 max732x_writeb(chip, 1, (uint8_t)msg); 345 break; 346 } 347 348 mutex_unlock(&chip->lock); 349 } 350 351 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 mutex_lock(&chip->irq_lock); 373 chip->irq_mask_cur = chip->irq_mask; 374 } 375 376 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 uint16_t new_irqs; 381 uint16_t level; 382 383 max732x_irq_update_mask(chip); 384 385 new_irqs = chip->irq_trig_fall | chip->irq_trig_raise; 386 while (new_irqs) { 387 level = __ffs(new_irqs); 388 max732x_gpio_direction_input(&chip->gpio_chip, level); 389 new_irqs &= ~(1 << level); 390 } 391 392 mutex_unlock(&chip->irq_lock); 393 } 394 395 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 uint16_t mask = 1 << off; 401 402 if (!(mask & chip->dir_input)) { 403 dev_dbg(&chip->client->dev, "%s port %d is output only\n", 404 chip->client->name, off); 405 return -EACCES; 406 } 407 408 if (!(type & IRQ_TYPE_EDGE_BOTH)) { 409 dev_err(&chip->client->dev, "irq %d: unsupported type %d\n", 410 d->irq, type); 411 return -EINVAL; 412 } 413 414 if (type & IRQ_TYPE_EDGE_FALLING) 415 chip->irq_trig_fall |= mask; 416 else 417 chip->irq_trig_fall &= ~mask; 418 419 if (type & IRQ_TYPE_EDGE_RISING) 420 chip->irq_trig_raise |= mask; 421 else 422 chip->irq_trig_raise &= ~mask; 423 424 return 0; 425 } 426 427 static int max732x_irq_set_wake(struct irq_data *data, unsigned int on) 428 { 429 struct max732x_chip *chip = irq_data_get_irq_chip_data(data); 430 431 irq_set_irq_wake(chip->client->irq, on); 432 return 0; 433 } 434 435 static struct irq_chip max732x_irq_chip = { 436 .name = "max732x", 437 .irq_mask = max732x_irq_mask, 438 .irq_unmask = max732x_irq_unmask, 439 .irq_bus_lock = max732x_irq_bus_lock, 440 .irq_bus_sync_unlock = max732x_irq_bus_sync_unlock, 441 .irq_set_type = max732x_irq_set_type, 442 .irq_set_wake = max732x_irq_set_wake, 443 }; 444 445 static uint8_t max732x_irq_pending(struct max732x_chip *chip) 446 { 447 uint8_t cur_stat; 448 uint8_t old_stat; 449 uint8_t trigger; 450 uint8_t pending; 451 uint16_t status; 452 int ret; 453 454 ret = max732x_readw(chip, &status); 455 if (ret) 456 return 0; 457 458 trigger = status >> 8; 459 trigger &= chip->irq_mask; 460 461 if (!trigger) 462 return 0; 463 464 cur_stat = status & 0xFF; 465 cur_stat &= chip->irq_mask; 466 467 old_stat = cur_stat ^ trigger; 468 469 pending = (old_stat & chip->irq_trig_fall) | 470 (cur_stat & chip->irq_trig_raise); 471 pending &= trigger; 472 473 return pending; 474 } 475 476 static irqreturn_t max732x_irq_handler(int irq, void *devid) 477 { 478 struct max732x_chip *chip = devid; 479 uint8_t pending; 480 uint8_t level; 481 482 pending = max732x_irq_pending(chip); 483 484 if (!pending) 485 return IRQ_HANDLED; 486 487 do { 488 level = __ffs(pending); 489 handle_nested_irq(irq_find_mapping(chip->gpio_chip.irq.domain, 490 level)); 491 492 pending &= ~(1 << level); 493 } while (pending); 494 495 return IRQ_HANDLED; 496 } 497 498 static int max732x_irq_setup(struct max732x_chip *chip, 499 const struct i2c_device_id *id) 500 { 501 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 int ret; 506 507 if (((pdata && pdata->irq_base) || client->irq) 508 && has_irq != INT_NONE) { 509 if (pdata) 510 irq_base = pdata->irq_base; 511 chip->irq_features = has_irq; 512 mutex_init(&chip->irq_lock); 513 514 ret = devm_request_threaded_irq(&client->dev, client->irq, 515 NULL, max732x_irq_handler, IRQF_ONESHOT | 516 IRQF_TRIGGER_FALLING | IRQF_SHARED, 517 dev_name(&client->dev), chip); 518 if (ret) { 519 dev_err(&client->dev, "failed to request irq %d\n", 520 client->irq); 521 return ret; 522 } 523 ret = gpiochip_irqchip_add_nested(&chip->gpio_chip, 524 &max732x_irq_chip, 525 irq_base, 526 handle_simple_irq, 527 IRQ_TYPE_NONE); 528 if (ret) { 529 dev_err(&client->dev, 530 "could not connect irqchip to gpiochip\n"); 531 return ret; 532 } 533 gpiochip_set_nested_irqchip(&chip->gpio_chip, 534 &max732x_irq_chip, 535 client->irq); 536 } 537 538 return 0; 539 } 540 541 #else /* CONFIG_GPIO_MAX732X_IRQ */ 542 static int max732x_irq_setup(struct max732x_chip *chip, 543 const struct i2c_device_id *id) 544 { 545 struct i2c_client *client = chip->client; 546 struct max732x_platform_data *pdata = dev_get_platdata(&client->dev); 547 int has_irq = max732x_features[id->driver_data] >> 32; 548 549 if (((pdata && pdata->irq_base) || client->irq) && has_irq != INT_NONE) 550 dev_warn(&client->dev, "interrupt support not compiled in\n"); 551 552 return 0; 553 } 554 #endif 555 556 static int max732x_setup_gpio(struct max732x_chip *chip, 557 const struct i2c_device_id *id, 558 unsigned gpio_start) 559 { 560 struct gpio_chip *gc = &chip->gpio_chip; 561 uint32_t id_data = (uint32_t)max732x_features[id->driver_data]; 562 int i, port = 0; 563 564 for (i = 0; i < 16; i++, id_data >>= 2) { 565 unsigned int mask = 1 << port; 566 567 switch (id_data & 0x3) { 568 case PORT_OUTPUT: 569 chip->dir_output |= mask; 570 break; 571 case PORT_INPUT: 572 chip->dir_input |= mask; 573 break; 574 case PORT_OPENDRAIN: 575 chip->dir_output |= mask; 576 chip->dir_input |= mask; 577 break; 578 default: 579 continue; 580 } 581 582 if (i < 8) 583 chip->mask_group_a |= mask; 584 port++; 585 } 586 587 if (chip->dir_input) 588 gc->direction_input = max732x_gpio_direction_input; 589 if (chip->dir_output) { 590 gc->direction_output = max732x_gpio_direction_output; 591 gc->set = max732x_gpio_set_value; 592 gc->set_multiple = max732x_gpio_set_multiple; 593 } 594 gc->get = max732x_gpio_get_value; 595 gc->can_sleep = true; 596 597 gc->base = gpio_start; 598 gc->ngpio = port; 599 gc->label = chip->client->name; 600 gc->parent = &chip->client->dev; 601 gc->owner = THIS_MODULE; 602 603 return port; 604 } 605 606 static struct max732x_platform_data *of_gpio_max732x(struct device *dev) 607 { 608 struct max732x_platform_data *pdata; 609 610 pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL); 611 if (!pdata) 612 return NULL; 613 614 pdata->gpio_base = -1; 615 616 return pdata; 617 } 618 619 static int max732x_probe(struct i2c_client *client, 620 const struct i2c_device_id *id) 621 { 622 struct max732x_platform_data *pdata; 623 struct device_node *node; 624 struct max732x_chip *chip; 625 struct i2c_client *c; 626 uint16_t addr_a, addr_b; 627 int ret, nr_port; 628 629 pdata = dev_get_platdata(&client->dev); 630 node = client->dev.of_node; 631 632 if (!pdata && node) 633 pdata = of_gpio_max732x(&client->dev); 634 635 if (!pdata) { 636 dev_dbg(&client->dev, "no platform data\n"); 637 return -EINVAL; 638 } 639 640 chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL); 641 if (chip == NULL) 642 return -ENOMEM; 643 chip->client = client; 644 645 nr_port = max732x_setup_gpio(chip, id, pdata->gpio_base); 646 chip->gpio_chip.parent = &client->dev; 647 648 addr_a = (client->addr & 0x0f) | 0x60; 649 addr_b = (client->addr & 0x0f) | 0x50; 650 651 switch (client->addr & 0x70) { 652 case 0x60: 653 chip->client_group_a = client; 654 if (nr_port > 8) { 655 c = i2c_new_dummy(client->adapter, addr_b); 656 chip->client_group_b = chip->client_dummy = c; 657 } 658 break; 659 case 0x50: 660 chip->client_group_b = client; 661 if (nr_port > 8) { 662 c = i2c_new_dummy(client->adapter, addr_a); 663 chip->client_group_a = chip->client_dummy = c; 664 } 665 break; 666 default: 667 dev_err(&client->dev, "invalid I2C address specified %02x\n", 668 client->addr); 669 ret = -EINVAL; 670 goto out_failed; 671 } 672 673 if (nr_port > 8 && !chip->client_dummy) { 674 dev_err(&client->dev, 675 "Failed to allocate second group I2C device\n"); 676 ret = -ENODEV; 677 goto out_failed; 678 } 679 680 mutex_init(&chip->lock); 681 682 ret = max732x_readb(chip, is_group_a(chip, 0), &chip->reg_out[0]); 683 if (ret) 684 goto out_failed; 685 if (nr_port > 8) { 686 ret = max732x_readb(chip, is_group_a(chip, 8), &chip->reg_out[1]); 687 if (ret) 688 goto out_failed; 689 } 690 691 ret = gpiochip_add_data(&chip->gpio_chip, chip); 692 if (ret) 693 goto out_failed; 694 695 ret = max732x_irq_setup(chip, id); 696 if (ret) { 697 gpiochip_remove(&chip->gpio_chip); 698 goto out_failed; 699 } 700 701 if (pdata && pdata->setup) { 702 ret = pdata->setup(client, chip->gpio_chip.base, 703 chip->gpio_chip.ngpio, pdata->context); 704 if (ret < 0) 705 dev_warn(&client->dev, "setup failed, %d\n", ret); 706 } 707 708 i2c_set_clientdata(client, chip); 709 return 0; 710 711 out_failed: 712 i2c_unregister_device(chip->client_dummy); 713 return ret; 714 } 715 716 static int max732x_remove(struct i2c_client *client) 717 { 718 struct max732x_platform_data *pdata = dev_get_platdata(&client->dev); 719 struct max732x_chip *chip = i2c_get_clientdata(client); 720 721 if (pdata && pdata->teardown) { 722 int ret; 723 724 ret = pdata->teardown(client, chip->gpio_chip.base, 725 chip->gpio_chip.ngpio, pdata->context); 726 if (ret < 0) { 727 dev_err(&client->dev, "%s failed, %d\n", 728 "teardown", ret); 729 return ret; 730 } 731 } 732 733 gpiochip_remove(&chip->gpio_chip); 734 735 /* unregister any dummy i2c_client */ 736 i2c_unregister_device(chip->client_dummy); 737 738 return 0; 739 } 740 741 static struct i2c_driver max732x_driver = { 742 .driver = { 743 .name = "max732x", 744 .of_match_table = of_match_ptr(max732x_of_table), 745 }, 746 .probe = max732x_probe, 747 .remove = max732x_remove, 748 .id_table = max732x_id, 749 }; 750 751 static int __init max732x_init(void) 752 { 753 return i2c_add_driver(&max732x_driver); 754 } 755 /* register after i2c postcore initcall and before 756 * subsys initcalls that may rely on these GPIOs 757 */ 758 subsys_initcall(max732x_init); 759 760 static void __exit max732x_exit(void) 761 { 762 i2c_del_driver(&max732x_driver); 763 } 764 module_exit(max732x_exit); 765 766 MODULE_AUTHOR("Eric Miao <eric.miao@marvell.com>"); 767 MODULE_DESCRIPTION("GPIO expander driver for MAX732X"); 768 MODULE_LICENSE("GPL"); 769