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 * 8 * Derived from drivers/gpio/pca953x.c 9 * 10 * This program is free software; you can redistribute it and/or modify 11 * it under the terms of the GNU General Public License as published by 12 * the Free Software Foundation; version 2 of the License. 13 */ 14 15 #include <linux/module.h> 16 #include <linux/init.h> 17 #include <linux/slab.h> 18 #include <linux/string.h> 19 #include <linux/gpio.h> 20 #include <linux/interrupt.h> 21 #include <linux/irq.h> 22 #include <linux/irqdomain.h> 23 #include <linux/i2c.h> 24 #include <linux/i2c/max732x.h> 25 #include <linux/of.h> 26 27 28 /* 29 * Each port of MAX732x (including MAX7319) falls into one of the 30 * following three types: 31 * 32 * - Push Pull Output 33 * - Input 34 * - Open Drain I/O 35 * 36 * designated by 'O', 'I' and 'P' individually according to MAXIM's 37 * datasheets. 'I' and 'P' ports are interrupt capables, some with 38 * a dedicated interrupt mask. 39 * 40 * There are two groups of I/O ports, each group usually includes 41 * up to 8 I/O ports, and is accessed by a specific I2C address: 42 * 43 * - Group A : by I2C address 0b'110xxxx 44 * - Group B : by I2C address 0b'101xxxx 45 * 46 * where 'xxxx' is decided by the connections of pin AD2/AD0. The 47 * address used also affects the initial state of output signals. 48 * 49 * Within each group of ports, there are five known combinations of 50 * I/O ports: 4I4O, 4P4O, 8I, 8P, 8O, see the definitions below for 51 * the detailed organization of these ports. Only Goup A is interrupt 52 * capable. 53 * 54 * GPIO numbers start from 'gpio_base + 0' to 'gpio_base + 8/16', 55 * and GPIOs from GROUP_A are numbered before those from GROUP_B 56 * (if there are two groups). 57 * 58 * NOTE: MAX7328/MAX7329 are drop-in replacements for PCF8574/a, so 59 * they are not supported by this driver. 60 */ 61 62 #define PORT_NONE 0x0 /* '/' No Port */ 63 #define PORT_OUTPUT 0x1 /* 'O' Push-Pull, Output Only */ 64 #define PORT_INPUT 0x2 /* 'I' Input Only */ 65 #define PORT_OPENDRAIN 0x3 /* 'P' Open-Drain, I/O */ 66 67 #define IO_4I4O 0x5AA5 /* O7 O6 I5 I4 I3 I2 O1 O0 */ 68 #define IO_4P4O 0x5FF5 /* O7 O6 P5 P4 P3 P2 O1 O0 */ 69 #define IO_8I 0xAAAA /* I7 I6 I5 I4 I3 I2 I1 I0 */ 70 #define IO_8P 0xFFFF /* P7 P6 P5 P4 P3 P2 P1 P0 */ 71 #define IO_8O 0x5555 /* O7 O6 O5 O4 O3 O2 O1 O0 */ 72 73 #define GROUP_A(x) ((x) & 0xffff) /* I2C Addr: 0b'110xxxx */ 74 #define GROUP_B(x) ((x) << 16) /* I2C Addr: 0b'101xxxx */ 75 76 #define INT_NONE 0x0 /* No interrupt capability */ 77 #define INT_NO_MASK 0x1 /* Has interrupts, no mask */ 78 #define INT_INDEP_MASK 0x2 /* Has interrupts, independent mask */ 79 #define INT_MERGED_MASK 0x3 /* Has interrupts, merged mask */ 80 81 #define INT_CAPS(x) (((uint64_t)(x)) << 32) 82 83 enum { 84 MAX7319, 85 MAX7320, 86 MAX7321, 87 MAX7322, 88 MAX7323, 89 MAX7324, 90 MAX7325, 91 MAX7326, 92 MAX7327, 93 }; 94 95 static uint64_t max732x_features[] = { 96 [MAX7319] = GROUP_A(IO_8I) | INT_CAPS(INT_MERGED_MASK), 97 [MAX7320] = GROUP_B(IO_8O), 98 [MAX7321] = GROUP_A(IO_8P) | INT_CAPS(INT_NO_MASK), 99 [MAX7322] = GROUP_A(IO_4I4O) | INT_CAPS(INT_MERGED_MASK), 100 [MAX7323] = GROUP_A(IO_4P4O) | INT_CAPS(INT_INDEP_MASK), 101 [MAX7324] = GROUP_A(IO_8I) | GROUP_B(IO_8O) | INT_CAPS(INT_MERGED_MASK), 102 [MAX7325] = GROUP_A(IO_8P) | GROUP_B(IO_8O) | INT_CAPS(INT_NO_MASK), 103 [MAX7326] = GROUP_A(IO_4I4O) | GROUP_B(IO_8O) | INT_CAPS(INT_MERGED_MASK), 104 [MAX7327] = GROUP_A(IO_4P4O) | GROUP_B(IO_8O) | INT_CAPS(INT_NO_MASK), 105 }; 106 107 static const struct i2c_device_id max732x_id[] = { 108 { "max7319", MAX7319 }, 109 { "max7320", MAX7320 }, 110 { "max7321", MAX7321 }, 111 { "max7322", MAX7322 }, 112 { "max7323", MAX7323 }, 113 { "max7324", MAX7324 }, 114 { "max7325", MAX7325 }, 115 { "max7326", MAX7326 }, 116 { "max7327", MAX7327 }, 117 { }, 118 }; 119 MODULE_DEVICE_TABLE(i2c, max732x_id); 120 121 #ifdef CONFIG_OF 122 static const struct of_device_id max732x_of_table[] = { 123 { .compatible = "maxim,max7319" }, 124 { .compatible = "maxim,max7320" }, 125 { .compatible = "maxim,max7321" }, 126 { .compatible = "maxim,max7322" }, 127 { .compatible = "maxim,max7323" }, 128 { .compatible = "maxim,max7324" }, 129 { .compatible = "maxim,max7325" }, 130 { .compatible = "maxim,max7326" }, 131 { .compatible = "maxim,max7327" }, 132 { } 133 }; 134 MODULE_DEVICE_TABLE(of, max732x_of_table); 135 #endif 136 137 struct max732x_chip { 138 struct gpio_chip gpio_chip; 139 140 struct i2c_client *client; /* "main" client */ 141 struct i2c_client *client_dummy; 142 struct i2c_client *client_group_a; 143 struct i2c_client *client_group_b; 144 145 unsigned int mask_group_a; 146 unsigned int dir_input; 147 unsigned int dir_output; 148 149 struct mutex lock; 150 uint8_t reg_out[2]; 151 152 #ifdef CONFIG_GPIO_MAX732X_IRQ 153 struct irq_domain *irq_domain; 154 struct mutex irq_lock; 155 int irq_base; 156 uint8_t irq_mask; 157 uint8_t irq_mask_cur; 158 uint8_t irq_trig_raise; 159 uint8_t irq_trig_fall; 160 uint8_t irq_features; 161 #endif 162 }; 163 164 static inline struct max732x_chip *to_max732x(struct gpio_chip *gc) 165 { 166 return container_of(gc, struct max732x_chip, gpio_chip); 167 } 168 169 static int max732x_writeb(struct max732x_chip *chip, int group_a, uint8_t val) 170 { 171 struct i2c_client *client; 172 int ret; 173 174 client = group_a ? chip->client_group_a : chip->client_group_b; 175 ret = i2c_smbus_write_byte(client, val); 176 if (ret < 0) { 177 dev_err(&client->dev, "failed writing\n"); 178 return ret; 179 } 180 181 return 0; 182 } 183 184 static int max732x_readb(struct max732x_chip *chip, int group_a, uint8_t *val) 185 { 186 struct i2c_client *client; 187 int ret; 188 189 client = group_a ? chip->client_group_a : chip->client_group_b; 190 ret = i2c_smbus_read_byte(client); 191 if (ret < 0) { 192 dev_err(&client->dev, "failed reading\n"); 193 return ret; 194 } 195 196 *val = (uint8_t)ret; 197 return 0; 198 } 199 200 static inline int is_group_a(struct max732x_chip *chip, unsigned off) 201 { 202 return (1u << off) & chip->mask_group_a; 203 } 204 205 static int max732x_gpio_get_value(struct gpio_chip *gc, unsigned off) 206 { 207 struct max732x_chip *chip = to_max732x(gc); 208 uint8_t reg_val; 209 int ret; 210 211 ret = max732x_readb(chip, is_group_a(chip, off), ®_val); 212 if (ret < 0) 213 return 0; 214 215 return reg_val & (1u << (off & 0x7)); 216 } 217 218 static void max732x_gpio_set_mask(struct gpio_chip *gc, unsigned off, int mask, 219 int val) 220 { 221 struct max732x_chip *chip = to_max732x(gc); 222 uint8_t reg_out; 223 int ret; 224 225 mutex_lock(&chip->lock); 226 227 reg_out = (off > 7) ? chip->reg_out[1] : chip->reg_out[0]; 228 reg_out = (reg_out & ~mask) | (val & mask); 229 230 ret = max732x_writeb(chip, is_group_a(chip, off), reg_out); 231 if (ret < 0) 232 goto out; 233 234 /* update the shadow register then */ 235 if (off > 7) 236 chip->reg_out[1] = reg_out; 237 else 238 chip->reg_out[0] = reg_out; 239 out: 240 mutex_unlock(&chip->lock); 241 } 242 243 static void max732x_gpio_set_value(struct gpio_chip *gc, unsigned off, int val) 244 { 245 unsigned base = off & ~0x7; 246 uint8_t mask = 1u << (off & 0x7); 247 248 max732x_gpio_set_mask(gc, base, mask, val << (off & 0x7)); 249 } 250 251 static void max732x_gpio_set_multiple(struct gpio_chip *gc, 252 unsigned long *mask, unsigned long *bits) 253 { 254 unsigned mask_lo = mask[0] & 0xff; 255 unsigned mask_hi = (mask[0] >> 8) & 0xff; 256 257 if (mask_lo) 258 max732x_gpio_set_mask(gc, 0, mask_lo, bits[0] & 0xff); 259 if (mask_hi) 260 max732x_gpio_set_mask(gc, 8, mask_hi, (bits[0] >> 8) & 0xff); 261 } 262 263 static int max732x_gpio_direction_input(struct gpio_chip *gc, unsigned off) 264 { 265 struct max732x_chip *chip = to_max732x(gc); 266 unsigned int mask = 1u << off; 267 268 if ((mask & chip->dir_input) == 0) { 269 dev_dbg(&chip->client->dev, "%s port %d is output only\n", 270 chip->client->name, off); 271 return -EACCES; 272 } 273 274 /* 275 * Open-drain pins must be set to high impedance (which is 276 * equivalent to output-high) to be turned into an input. 277 */ 278 if ((mask & chip->dir_output)) 279 max732x_gpio_set_value(gc, off, 1); 280 281 return 0; 282 } 283 284 static int max732x_gpio_direction_output(struct gpio_chip *gc, 285 unsigned off, int val) 286 { 287 struct max732x_chip *chip = to_max732x(gc); 288 unsigned int mask = 1u << off; 289 290 if ((mask & chip->dir_output) == 0) { 291 dev_dbg(&chip->client->dev, "%s port %d is input only\n", 292 chip->client->name, off); 293 return -EACCES; 294 } 295 296 max732x_gpio_set_value(gc, off, val); 297 return 0; 298 } 299 300 #ifdef CONFIG_GPIO_MAX732X_IRQ 301 static int max732x_writew(struct max732x_chip *chip, uint16_t val) 302 { 303 int ret; 304 305 val = cpu_to_le16(val); 306 307 ret = i2c_master_send(chip->client_group_a, (char *)&val, 2); 308 if (ret < 0) { 309 dev_err(&chip->client_group_a->dev, "failed writing\n"); 310 return ret; 311 } 312 313 return 0; 314 } 315 316 static int max732x_readw(struct max732x_chip *chip, uint16_t *val) 317 { 318 int ret; 319 320 ret = i2c_master_recv(chip->client_group_a, (char *)val, 2); 321 if (ret < 0) { 322 dev_err(&chip->client_group_a->dev, "failed reading\n"); 323 return ret; 324 } 325 326 *val = le16_to_cpu(*val); 327 return 0; 328 } 329 330 static void max732x_irq_update_mask(struct max732x_chip *chip) 331 { 332 uint16_t msg; 333 334 if (chip->irq_mask == chip->irq_mask_cur) 335 return; 336 337 chip->irq_mask = chip->irq_mask_cur; 338 339 if (chip->irq_features == INT_NO_MASK) 340 return; 341 342 mutex_lock(&chip->lock); 343 344 switch (chip->irq_features) { 345 case INT_INDEP_MASK: 346 msg = (chip->irq_mask << 8) | chip->reg_out[0]; 347 max732x_writew(chip, msg); 348 break; 349 350 case INT_MERGED_MASK: 351 msg = chip->irq_mask | chip->reg_out[0]; 352 max732x_writeb(chip, 1, (uint8_t)msg); 353 break; 354 } 355 356 mutex_unlock(&chip->lock); 357 } 358 359 static int max732x_gpio_to_irq(struct gpio_chip *gc, unsigned off) 360 { 361 struct max732x_chip *chip = to_max732x(gc); 362 363 if (chip->irq_domain) { 364 return irq_create_mapping(chip->irq_domain, 365 chip->irq_base + off); 366 } else { 367 return -ENXIO; 368 } 369 } 370 371 static void max732x_irq_mask(struct irq_data *d) 372 { 373 struct max732x_chip *chip = irq_data_get_irq_chip_data(d); 374 375 chip->irq_mask_cur &= ~(1 << d->hwirq); 376 } 377 378 static void max732x_irq_unmask(struct irq_data *d) 379 { 380 struct max732x_chip *chip = irq_data_get_irq_chip_data(d); 381 382 chip->irq_mask_cur |= 1 << d->hwirq; 383 } 384 385 static void max732x_irq_bus_lock(struct irq_data *d) 386 { 387 struct max732x_chip *chip = irq_data_get_irq_chip_data(d); 388 389 mutex_lock(&chip->irq_lock); 390 chip->irq_mask_cur = chip->irq_mask; 391 } 392 393 static void max732x_irq_bus_sync_unlock(struct irq_data *d) 394 { 395 struct max732x_chip *chip = irq_data_get_irq_chip_data(d); 396 uint16_t new_irqs; 397 uint16_t level; 398 399 max732x_irq_update_mask(chip); 400 401 new_irqs = chip->irq_trig_fall | chip->irq_trig_raise; 402 while (new_irqs) { 403 level = __ffs(new_irqs); 404 max732x_gpio_direction_input(&chip->gpio_chip, level); 405 new_irqs &= ~(1 << level); 406 } 407 408 mutex_unlock(&chip->irq_lock); 409 } 410 411 static int max732x_irq_set_type(struct irq_data *d, unsigned int type) 412 { 413 struct max732x_chip *chip = irq_data_get_irq_chip_data(d); 414 uint16_t off = d->hwirq; 415 uint16_t mask = 1 << off; 416 417 if (!(mask & chip->dir_input)) { 418 dev_dbg(&chip->client->dev, "%s port %d is output only\n", 419 chip->client->name, off); 420 return -EACCES; 421 } 422 423 if (!(type & IRQ_TYPE_EDGE_BOTH)) { 424 dev_err(&chip->client->dev, "irq %d: unsupported type %d\n", 425 d->irq, type); 426 return -EINVAL; 427 } 428 429 if (type & IRQ_TYPE_EDGE_FALLING) 430 chip->irq_trig_fall |= mask; 431 else 432 chip->irq_trig_fall &= ~mask; 433 434 if (type & IRQ_TYPE_EDGE_RISING) 435 chip->irq_trig_raise |= mask; 436 else 437 chip->irq_trig_raise &= ~mask; 438 439 return 0; 440 } 441 442 static struct irq_chip max732x_irq_chip = { 443 .name = "max732x", 444 .irq_mask = max732x_irq_mask, 445 .irq_unmask = max732x_irq_unmask, 446 .irq_bus_lock = max732x_irq_bus_lock, 447 .irq_bus_sync_unlock = max732x_irq_bus_sync_unlock, 448 .irq_set_type = max732x_irq_set_type, 449 }; 450 451 static uint8_t max732x_irq_pending(struct max732x_chip *chip) 452 { 453 uint8_t cur_stat; 454 uint8_t old_stat; 455 uint8_t trigger; 456 uint8_t pending; 457 uint16_t status; 458 int ret; 459 460 ret = max732x_readw(chip, &status); 461 if (ret) 462 return 0; 463 464 trigger = status >> 8; 465 trigger &= chip->irq_mask; 466 467 if (!trigger) 468 return 0; 469 470 cur_stat = status & 0xFF; 471 cur_stat &= chip->irq_mask; 472 473 old_stat = cur_stat ^ trigger; 474 475 pending = (old_stat & chip->irq_trig_fall) | 476 (cur_stat & chip->irq_trig_raise); 477 pending &= trigger; 478 479 return pending; 480 } 481 482 static irqreturn_t max732x_irq_handler(int irq, void *devid) 483 { 484 struct max732x_chip *chip = devid; 485 uint8_t pending; 486 uint8_t level; 487 488 pending = max732x_irq_pending(chip); 489 490 if (!pending) 491 return IRQ_HANDLED; 492 493 do { 494 level = __ffs(pending); 495 handle_nested_irq(irq_find_mapping(chip->irq_domain, level)); 496 497 pending &= ~(1 << level); 498 } while (pending); 499 500 return IRQ_HANDLED; 501 } 502 503 static int max732x_irq_map(struct irq_domain *h, unsigned int virq, 504 irq_hw_number_t hw) 505 { 506 struct max732x_chip *chip = h->host_data; 507 508 if (!(chip->dir_input & (1 << hw))) { 509 dev_err(&chip->client->dev, 510 "Attempt to map output line as IRQ line: %lu\n", 511 hw); 512 return -EPERM; 513 } 514 515 irq_set_chip_data(virq, chip); 516 irq_set_chip_and_handler(virq, &max732x_irq_chip, 517 handle_edge_irq); 518 irq_set_nested_thread(virq, 1); 519 #ifdef CONFIG_ARM 520 /* ARM needs us to explicitly flag the IRQ as valid 521 * and will set them noprobe when we do so. */ 522 set_irq_flags(virq, IRQF_VALID); 523 #else 524 irq_set_noprobe(virq); 525 #endif 526 527 return 0; 528 } 529 530 static struct irq_domain_ops max732x_irq_domain_ops = { 531 .map = max732x_irq_map, 532 .xlate = irq_domain_xlate_twocell, 533 }; 534 535 static void max732x_irq_teardown(struct max732x_chip *chip) 536 { 537 if (chip->client->irq && chip->irq_domain) 538 irq_domain_remove(chip->irq_domain); 539 } 540 541 static int max732x_irq_setup(struct max732x_chip *chip, 542 const struct i2c_device_id *id) 543 { 544 struct i2c_client *client = chip->client; 545 struct max732x_platform_data *pdata = dev_get_platdata(&client->dev); 546 int has_irq = max732x_features[id->driver_data] >> 32; 547 int ret; 548 549 if (((pdata && pdata->irq_base) || client->irq) 550 && has_irq != INT_NONE) { 551 if (pdata) 552 chip->irq_base = pdata->irq_base; 553 chip->irq_features = has_irq; 554 mutex_init(&chip->irq_lock); 555 556 chip->irq_domain = irq_domain_add_simple(client->dev.of_node, 557 chip->gpio_chip.ngpio, chip->irq_base, 558 &max732x_irq_domain_ops, chip); 559 if (!chip->irq_domain) { 560 dev_err(&client->dev, "Failed to create IRQ domain\n"); 561 return -ENOMEM; 562 } 563 564 ret = request_threaded_irq(client->irq, 565 NULL, 566 max732x_irq_handler, 567 IRQF_TRIGGER_FALLING | IRQF_ONESHOT, 568 dev_name(&client->dev), chip); 569 if (ret) { 570 dev_err(&client->dev, "failed to request irq %d\n", 571 client->irq); 572 goto out_failed; 573 } 574 575 chip->gpio_chip.to_irq = max732x_gpio_to_irq; 576 } 577 578 return 0; 579 580 out_failed: 581 max732x_irq_teardown(chip); 582 return ret; 583 } 584 585 #else /* CONFIG_GPIO_MAX732X_IRQ */ 586 static int max732x_irq_setup(struct max732x_chip *chip, 587 const struct i2c_device_id *id) 588 { 589 struct i2c_client *client = chip->client; 590 struct max732x_platform_data *pdata = dev_get_platdata(&client->dev); 591 int has_irq = max732x_features[id->driver_data] >> 32; 592 593 if (((pdata && pdata->irq_base) || client->irq) && has_irq != INT_NONE) 594 dev_warn(&client->dev, "interrupt support not compiled in\n"); 595 596 return 0; 597 } 598 599 static void max732x_irq_teardown(struct max732x_chip *chip) 600 { 601 } 602 #endif 603 604 static int max732x_setup_gpio(struct max732x_chip *chip, 605 const struct i2c_device_id *id, 606 unsigned gpio_start) 607 { 608 struct gpio_chip *gc = &chip->gpio_chip; 609 uint32_t id_data = (uint32_t)max732x_features[id->driver_data]; 610 int i, port = 0; 611 612 for (i = 0; i < 16; i++, id_data >>= 2) { 613 unsigned int mask = 1 << port; 614 615 switch (id_data & 0x3) { 616 case PORT_OUTPUT: 617 chip->dir_output |= mask; 618 break; 619 case PORT_INPUT: 620 chip->dir_input |= mask; 621 break; 622 case PORT_OPENDRAIN: 623 chip->dir_output |= mask; 624 chip->dir_input |= mask; 625 break; 626 default: 627 continue; 628 } 629 630 if (i < 8) 631 chip->mask_group_a |= mask; 632 port++; 633 } 634 635 if (chip->dir_input) 636 gc->direction_input = max732x_gpio_direction_input; 637 if (chip->dir_output) { 638 gc->direction_output = max732x_gpio_direction_output; 639 gc->set = max732x_gpio_set_value; 640 gc->set_multiple = max732x_gpio_set_multiple; 641 } 642 gc->get = max732x_gpio_get_value; 643 gc->can_sleep = true; 644 645 gc->base = gpio_start; 646 gc->ngpio = port; 647 gc->label = chip->client->name; 648 gc->owner = THIS_MODULE; 649 650 return port; 651 } 652 653 static struct max732x_platform_data *of_gpio_max732x(struct device *dev) 654 { 655 struct max732x_platform_data *pdata; 656 657 pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL); 658 if (!pdata) 659 return NULL; 660 661 pdata->gpio_base = -1; 662 663 return pdata; 664 } 665 666 static int max732x_probe(struct i2c_client *client, 667 const struct i2c_device_id *id) 668 { 669 struct max732x_platform_data *pdata; 670 struct device_node *node; 671 struct max732x_chip *chip; 672 struct i2c_client *c; 673 uint16_t addr_a, addr_b; 674 int ret, nr_port; 675 676 pdata = dev_get_platdata(&client->dev); 677 node = client->dev.of_node; 678 679 if (!pdata && node) 680 pdata = of_gpio_max732x(&client->dev); 681 682 if (!pdata) { 683 dev_dbg(&client->dev, "no platform data\n"); 684 return -EINVAL; 685 } 686 687 chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL); 688 if (chip == NULL) 689 return -ENOMEM; 690 chip->client = client; 691 692 nr_port = max732x_setup_gpio(chip, id, pdata->gpio_base); 693 chip->gpio_chip.dev = &client->dev; 694 695 addr_a = (client->addr & 0x0f) | 0x60; 696 addr_b = (client->addr & 0x0f) | 0x50; 697 698 switch (client->addr & 0x70) { 699 case 0x60: 700 chip->client_group_a = client; 701 if (nr_port > 8) { 702 c = i2c_new_dummy(client->adapter, addr_b); 703 chip->client_group_b = chip->client_dummy = c; 704 } 705 break; 706 case 0x50: 707 chip->client_group_b = client; 708 if (nr_port > 8) { 709 c = i2c_new_dummy(client->adapter, addr_a); 710 chip->client_group_a = chip->client_dummy = c; 711 } 712 break; 713 default: 714 dev_err(&client->dev, "invalid I2C address specified %02x\n", 715 client->addr); 716 ret = -EINVAL; 717 goto out_failed; 718 } 719 720 if (nr_port > 8 && !chip->client_dummy) { 721 dev_err(&client->dev, 722 "Failed to allocate second group I2C device\n"); 723 ret = -ENODEV; 724 goto out_failed; 725 } 726 727 mutex_init(&chip->lock); 728 729 max732x_readb(chip, is_group_a(chip, 0), &chip->reg_out[0]); 730 if (nr_port > 8) 731 max732x_readb(chip, is_group_a(chip, 8), &chip->reg_out[1]); 732 733 ret = max732x_irq_setup(chip, id); 734 if (ret) 735 goto out_failed; 736 737 ret = gpiochip_add(&chip->gpio_chip); 738 if (ret) 739 goto out_failed; 740 741 if (pdata && pdata->setup) { 742 ret = pdata->setup(client, chip->gpio_chip.base, 743 chip->gpio_chip.ngpio, pdata->context); 744 if (ret < 0) 745 dev_warn(&client->dev, "setup failed, %d\n", ret); 746 } 747 748 i2c_set_clientdata(client, chip); 749 return 0; 750 751 out_failed: 752 if (chip->client_dummy) 753 i2c_unregister_device(chip->client_dummy); 754 max732x_irq_teardown(chip); 755 return ret; 756 } 757 758 static int max732x_remove(struct i2c_client *client) 759 { 760 struct max732x_platform_data *pdata = dev_get_platdata(&client->dev); 761 struct max732x_chip *chip = i2c_get_clientdata(client); 762 763 if (pdata && pdata->teardown) { 764 int ret; 765 766 ret = pdata->teardown(client, chip->gpio_chip.base, 767 chip->gpio_chip.ngpio, pdata->context); 768 if (ret < 0) { 769 dev_err(&client->dev, "%s failed, %d\n", 770 "teardown", ret); 771 return ret; 772 } 773 } 774 775 gpiochip_remove(&chip->gpio_chip); 776 777 max732x_irq_teardown(chip); 778 779 /* unregister any dummy i2c_client */ 780 if (chip->client_dummy) 781 i2c_unregister_device(chip->client_dummy); 782 783 return 0; 784 } 785 786 static struct i2c_driver max732x_driver = { 787 .driver = { 788 .name = "max732x", 789 .owner = THIS_MODULE, 790 .of_match_table = of_match_ptr(max732x_of_table), 791 }, 792 .probe = max732x_probe, 793 .remove = max732x_remove, 794 .id_table = max732x_id, 795 }; 796 797 static int __init max732x_init(void) 798 { 799 return i2c_add_driver(&max732x_driver); 800 } 801 /* register after i2c postcore initcall and before 802 * subsys initcalls that may rely on these GPIOs 803 */ 804 subsys_initcall(max732x_init); 805 806 static void __exit max732x_exit(void) 807 { 808 i2c_del_driver(&max732x_driver); 809 } 810 module_exit(max732x_exit); 811 812 MODULE_AUTHOR("Eric Miao <eric.miao@marvell.com>"); 813 MODULE_DESCRIPTION("GPIO expander driver for MAX732X"); 814 MODULE_LICENSE("GPL"); 815