1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * I2C multiplexer 4 * 5 * Copyright (c) 2008-2009 Rodolfo Giometti <giometti@linux.it> 6 * Copyright (c) 2008-2009 Eurotech S.p.A. <info@eurotech.it> 7 * 8 * This module supports the PCA954x and PCA984x series of I2C multiplexer/switch 9 * chips made by NXP Semiconductors. 10 * This includes the: 11 * PCA9540, PCA9542, PCA9543, PCA9544, PCA9545, PCA9546, PCA9547, 12 * PCA9548, PCA9846, PCA9847, PCA9848 and PCA9849. 13 * 14 * It's also compatible to Maxims MAX735x I2C switch chips, which are controlled 15 * as the NXP PCA9548 and the MAX736x chips that act like the PCA9544. 16 * 17 * This includes the: 18 * MAX7356, MAX7357, MAX7358, MAX7367, MAX7368 and MAX7369 19 * 20 * These chips are all controlled via the I2C bus itself, and all have a 21 * single 8-bit register. The upstream "parent" bus fans out to two, 22 * four, or eight downstream busses or channels; which of these 23 * are selected is determined by the chip type and register contents. A 24 * mux can select only one sub-bus at a time; a switch can select any 25 * combination simultaneously. 26 * 27 * Based on: 28 * pca954x.c from Kumar Gala <galak@kernel.crashing.org> 29 * Copyright (C) 2006 30 * 31 * Based on: 32 * pca954x.c from Ken Harrenstien 33 * Copyright (C) 2004 Google, Inc. (Ken Harrenstien) 34 * 35 * Based on: 36 * i2c-virtual_cb.c from Brian Kuschak <bkuschak@yahoo.com> 37 * and 38 * pca9540.c from Jean Delvare <jdelvare@suse.de>. 39 */ 40 41 #include <linux/device.h> 42 #include <linux/delay.h> 43 #include <linux/gpio/consumer.h> 44 #include <linux/i2c.h> 45 #include <linux/i2c-mux.h> 46 #include <linux/interrupt.h> 47 #include <linux/irq.h> 48 #include <linux/module.h> 49 #include <linux/pm.h> 50 #include <linux/property.h> 51 #include <linux/regulator/consumer.h> 52 #include <linux/slab.h> 53 #include <linux/spinlock.h> 54 #include <dt-bindings/mux/mux.h> 55 56 #define PCA954X_MAX_NCHANS 8 57 58 #define PCA954X_IRQ_OFFSET 4 59 60 /* 61 * MAX7357's configuration register is writeable after POR, but 62 * can be locked by setting the basic mode bit. MAX7358 configuration 63 * register is locked by default and needs to be unlocked first. 64 * The configuration register holds the following settings: 65 */ 66 #define MAX7357_CONF_INT_ENABLE BIT(0) 67 #define MAX7357_CONF_FLUSH_OUT BIT(1) 68 #define MAX7357_CONF_RELEASE_INT BIT(2) 69 #define MAX7357_CONF_DISCON_SINGLE_CHAN BIT(4) 70 #define MAX7357_CONF_PRECONNECT_TEST BIT(7) 71 72 #define MAX7357_POR_DEFAULT_CONF MAX7357_CONF_INT_ENABLE 73 74 enum pca_type { 75 max_7356, 76 max_7357, 77 max_7358, 78 max_7367, 79 max_7368, 80 max_7369, 81 pca_9540, 82 pca_9542, 83 pca_9543, 84 pca_9544, 85 pca_9545, 86 pca_9546, 87 pca_9547, 88 pca_9548, 89 pca_9846, 90 pca_9847, 91 pca_9848, 92 pca_9849, 93 }; 94 95 struct chip_desc { 96 u8 nchans; 97 u8 enable; /* used for muxes only */ 98 u8 has_irq; 99 enum muxtype { 100 pca954x_ismux = 0, 101 pca954x_isswi 102 } muxtype; 103 struct i2c_device_identity id; 104 }; 105 106 struct pca954x { 107 const struct chip_desc *chip; 108 109 u8 last_chan; /* last register value */ 110 /* MUX_IDLE_AS_IS, MUX_IDLE_DISCONNECT or >= 0 for channel */ 111 s32 idle_state; 112 113 struct i2c_client *client; 114 115 struct irq_domain *irq; 116 unsigned int irq_mask; 117 raw_spinlock_t lock; 118 struct regulator *supply; 119 }; 120 121 /* Provide specs for the MAX735x, PCA954x and PCA984x types we know about */ 122 static const struct chip_desc chips[] = { 123 [max_7356] = { 124 .nchans = 8, 125 .muxtype = pca954x_isswi, 126 .id = { .manufacturer_id = I2C_DEVICE_ID_NONE }, 127 }, 128 [max_7357] = { 129 .nchans = 8, 130 .muxtype = pca954x_isswi, 131 .id = { .manufacturer_id = I2C_DEVICE_ID_NONE }, 132 /* 133 * No interrupt controller support. The interrupt 134 * provides information about stuck channels. 135 */ 136 }, 137 [max_7358] = { 138 .nchans = 8, 139 .muxtype = pca954x_isswi, 140 .id = { .manufacturer_id = I2C_DEVICE_ID_NONE }, 141 /* 142 * No interrupt controller support. The interrupt 143 * provides information about stuck channels. 144 */ 145 }, 146 [max_7367] = { 147 .nchans = 4, 148 .muxtype = pca954x_isswi, 149 .has_irq = 1, 150 .id = { .manufacturer_id = I2C_DEVICE_ID_NONE }, 151 }, 152 [max_7368] = { 153 .nchans = 4, 154 .muxtype = pca954x_isswi, 155 .id = { .manufacturer_id = I2C_DEVICE_ID_NONE }, 156 }, 157 [max_7369] = { 158 .nchans = 4, 159 .enable = 0x4, 160 .muxtype = pca954x_ismux, 161 .has_irq = 1, 162 .id = { .manufacturer_id = I2C_DEVICE_ID_NONE }, 163 }, 164 [pca_9540] = { 165 .nchans = 2, 166 .enable = 0x4, 167 .muxtype = pca954x_ismux, 168 .id = { .manufacturer_id = I2C_DEVICE_ID_NONE }, 169 }, 170 [pca_9542] = { 171 .nchans = 2, 172 .enable = 0x4, 173 .has_irq = 1, 174 .muxtype = pca954x_ismux, 175 .id = { .manufacturer_id = I2C_DEVICE_ID_NONE }, 176 }, 177 [pca_9543] = { 178 .nchans = 2, 179 .has_irq = 1, 180 .muxtype = pca954x_isswi, 181 .id = { .manufacturer_id = I2C_DEVICE_ID_NONE }, 182 }, 183 [pca_9544] = { 184 .nchans = 4, 185 .enable = 0x4, 186 .has_irq = 1, 187 .muxtype = pca954x_ismux, 188 .id = { .manufacturer_id = I2C_DEVICE_ID_NONE }, 189 }, 190 [pca_9545] = { 191 .nchans = 4, 192 .has_irq = 1, 193 .muxtype = pca954x_isswi, 194 .id = { .manufacturer_id = I2C_DEVICE_ID_NONE }, 195 }, 196 [pca_9546] = { 197 .nchans = 4, 198 .muxtype = pca954x_isswi, 199 .id = { .manufacturer_id = I2C_DEVICE_ID_NONE }, 200 }, 201 [pca_9547] = { 202 .nchans = 8, 203 .enable = 0x8, 204 .muxtype = pca954x_ismux, 205 .id = { .manufacturer_id = I2C_DEVICE_ID_NONE }, 206 }, 207 [pca_9548] = { 208 .nchans = 8, 209 .muxtype = pca954x_isswi, 210 .id = { .manufacturer_id = I2C_DEVICE_ID_NONE }, 211 }, 212 [pca_9846] = { 213 .nchans = 4, 214 .muxtype = pca954x_isswi, 215 .id = { 216 .manufacturer_id = I2C_DEVICE_ID_NXP_SEMICONDUCTORS, 217 .part_id = 0x10b, 218 }, 219 }, 220 [pca_9847] = { 221 .nchans = 8, 222 .enable = 0x8, 223 .muxtype = pca954x_ismux, 224 .id = { 225 .manufacturer_id = I2C_DEVICE_ID_NXP_SEMICONDUCTORS, 226 .part_id = 0x108, 227 }, 228 }, 229 [pca_9848] = { 230 .nchans = 8, 231 .muxtype = pca954x_isswi, 232 .id = { 233 .manufacturer_id = I2C_DEVICE_ID_NXP_SEMICONDUCTORS, 234 .part_id = 0x10a, 235 }, 236 }, 237 [pca_9849] = { 238 .nchans = 4, 239 .enable = 0x4, 240 .muxtype = pca954x_ismux, 241 .id = { 242 .manufacturer_id = I2C_DEVICE_ID_NXP_SEMICONDUCTORS, 243 .part_id = 0x109, 244 }, 245 }, 246 }; 247 248 static const struct i2c_device_id pca954x_id[] = { 249 { "max7356", max_7356 }, 250 { "max7357", max_7357 }, 251 { "max7358", max_7358 }, 252 { "max7367", max_7367 }, 253 { "max7368", max_7368 }, 254 { "max7369", max_7369 }, 255 { "pca9540", pca_9540 }, 256 { "pca9542", pca_9542 }, 257 { "pca9543", pca_9543 }, 258 { "pca9544", pca_9544 }, 259 { "pca9545", pca_9545 }, 260 { "pca9546", pca_9546 }, 261 { "pca9547", pca_9547 }, 262 { "pca9548", pca_9548 }, 263 { "pca9846", pca_9846 }, 264 { "pca9847", pca_9847 }, 265 { "pca9848", pca_9848 }, 266 { "pca9849", pca_9849 }, 267 { } 268 }; 269 MODULE_DEVICE_TABLE(i2c, pca954x_id); 270 271 static const struct of_device_id pca954x_of_match[] = { 272 { .compatible = "maxim,max7356", .data = &chips[max_7356] }, 273 { .compatible = "maxim,max7357", .data = &chips[max_7357] }, 274 { .compatible = "maxim,max7358", .data = &chips[max_7358] }, 275 { .compatible = "maxim,max7367", .data = &chips[max_7367] }, 276 { .compatible = "maxim,max7368", .data = &chips[max_7368] }, 277 { .compatible = "maxim,max7369", .data = &chips[max_7369] }, 278 { .compatible = "nxp,pca9540", .data = &chips[pca_9540] }, 279 { .compatible = "nxp,pca9542", .data = &chips[pca_9542] }, 280 { .compatible = "nxp,pca9543", .data = &chips[pca_9543] }, 281 { .compatible = "nxp,pca9544", .data = &chips[pca_9544] }, 282 { .compatible = "nxp,pca9545", .data = &chips[pca_9545] }, 283 { .compatible = "nxp,pca9546", .data = &chips[pca_9546] }, 284 { .compatible = "nxp,pca9547", .data = &chips[pca_9547] }, 285 { .compatible = "nxp,pca9548", .data = &chips[pca_9548] }, 286 { .compatible = "nxp,pca9846", .data = &chips[pca_9846] }, 287 { .compatible = "nxp,pca9847", .data = &chips[pca_9847] }, 288 { .compatible = "nxp,pca9848", .data = &chips[pca_9848] }, 289 { .compatible = "nxp,pca9849", .data = &chips[pca_9849] }, 290 {} 291 }; 292 MODULE_DEVICE_TABLE(of, pca954x_of_match); 293 294 /* Write to mux register. Don't use i2c_transfer()/i2c_smbus_xfer() 295 for this as they will try to lock adapter a second time */ 296 static int pca954x_reg_write(struct i2c_adapter *adap, 297 struct i2c_client *client, u8 val) 298 { 299 union i2c_smbus_data dummy; 300 301 return __i2c_smbus_xfer(adap, client->addr, client->flags, 302 I2C_SMBUS_WRITE, val, 303 I2C_SMBUS_BYTE, &dummy); 304 } 305 306 static u8 pca954x_regval(struct pca954x *data, u8 chan) 307 { 308 /* We make switches look like muxes, not sure how to be smarter. */ 309 if (data->chip->muxtype == pca954x_ismux) 310 return chan | data->chip->enable; 311 else 312 return 1 << chan; 313 } 314 315 static int pca954x_select_chan(struct i2c_mux_core *muxc, u32 chan) 316 { 317 struct pca954x *data = i2c_mux_priv(muxc); 318 struct i2c_client *client = data->client; 319 u8 regval; 320 int ret = 0; 321 322 regval = pca954x_regval(data, chan); 323 /* Only select the channel if its different from the last channel */ 324 if (data->last_chan != regval) { 325 ret = pca954x_reg_write(muxc->parent, client, regval); 326 data->last_chan = ret < 0 ? 0 : regval; 327 } 328 329 return ret; 330 } 331 332 static int pca954x_deselect_mux(struct i2c_mux_core *muxc, u32 chan) 333 { 334 struct pca954x *data = i2c_mux_priv(muxc); 335 struct i2c_client *client = data->client; 336 s32 idle_state; 337 338 idle_state = READ_ONCE(data->idle_state); 339 if (idle_state >= 0) 340 /* Set the mux back to a predetermined channel */ 341 return pca954x_select_chan(muxc, idle_state); 342 343 if (idle_state == MUX_IDLE_DISCONNECT) { 344 /* Deselect active channel */ 345 data->last_chan = 0; 346 return pca954x_reg_write(muxc->parent, client, 347 data->last_chan); 348 } 349 350 /* otherwise leave as-is */ 351 352 return 0; 353 } 354 355 static ssize_t idle_state_show(struct device *dev, 356 struct device_attribute *attr, 357 char *buf) 358 { 359 struct i2c_client *client = to_i2c_client(dev); 360 struct i2c_mux_core *muxc = i2c_get_clientdata(client); 361 struct pca954x *data = i2c_mux_priv(muxc); 362 363 return sprintf(buf, "%d\n", READ_ONCE(data->idle_state)); 364 } 365 366 static ssize_t idle_state_store(struct device *dev, 367 struct device_attribute *attr, 368 const char *buf, size_t count) 369 { 370 struct i2c_client *client = to_i2c_client(dev); 371 struct i2c_mux_core *muxc = i2c_get_clientdata(client); 372 struct pca954x *data = i2c_mux_priv(muxc); 373 int val; 374 int ret; 375 376 ret = kstrtoint(buf, 0, &val); 377 if (ret < 0) 378 return ret; 379 380 if (val != MUX_IDLE_AS_IS && val != MUX_IDLE_DISCONNECT && 381 (val < 0 || val >= data->chip->nchans)) 382 return -EINVAL; 383 384 i2c_lock_bus(muxc->parent, I2C_LOCK_SEGMENT); 385 386 WRITE_ONCE(data->idle_state, val); 387 /* 388 * Set the mux into a state consistent with the new 389 * idle_state. 390 */ 391 if (data->last_chan || val != MUX_IDLE_DISCONNECT) 392 ret = pca954x_deselect_mux(muxc, 0); 393 394 i2c_unlock_bus(muxc->parent, I2C_LOCK_SEGMENT); 395 396 return ret < 0 ? ret : count; 397 } 398 399 static DEVICE_ATTR_RW(idle_state); 400 401 static irqreturn_t pca954x_irq_handler(int irq, void *dev_id) 402 { 403 struct pca954x *data = dev_id; 404 unsigned long pending; 405 int ret, i; 406 407 ret = i2c_smbus_read_byte(data->client); 408 if (ret < 0) 409 return IRQ_NONE; 410 411 pending = (ret >> PCA954X_IRQ_OFFSET) & (BIT(data->chip->nchans) - 1); 412 for_each_set_bit(i, &pending, data->chip->nchans) 413 handle_nested_irq(irq_linear_revmap(data->irq, i)); 414 415 return IRQ_RETVAL(pending); 416 } 417 418 static int pca954x_irq_set_type(struct irq_data *idata, unsigned int type) 419 { 420 if ((type & IRQ_TYPE_SENSE_MASK) != IRQ_TYPE_LEVEL_LOW) 421 return -EINVAL; 422 return 0; 423 } 424 425 static struct irq_chip pca954x_irq_chip = { 426 .name = "i2c-mux-pca954x", 427 .irq_set_type = pca954x_irq_set_type, 428 }; 429 430 static int pca954x_irq_setup(struct i2c_mux_core *muxc) 431 { 432 struct pca954x *data = i2c_mux_priv(muxc); 433 struct i2c_client *client = data->client; 434 int c, irq; 435 436 if (!data->chip->has_irq || client->irq <= 0) 437 return 0; 438 439 raw_spin_lock_init(&data->lock); 440 441 data->irq = irq_domain_add_linear(client->dev.of_node, 442 data->chip->nchans, 443 &irq_domain_simple_ops, data); 444 if (!data->irq) 445 return -ENODEV; 446 447 for (c = 0; c < data->chip->nchans; c++) { 448 irq = irq_create_mapping(data->irq, c); 449 if (!irq) { 450 dev_err(&client->dev, "failed irq create map\n"); 451 return -EINVAL; 452 } 453 irq_set_chip_data(irq, data); 454 irq_set_chip_and_handler(irq, &pca954x_irq_chip, 455 handle_simple_irq); 456 } 457 458 return 0; 459 } 460 461 static void pca954x_cleanup(struct i2c_mux_core *muxc) 462 { 463 struct pca954x *data = i2c_mux_priv(muxc); 464 int c, irq; 465 466 regulator_disable(data->supply); 467 468 if (data->irq) { 469 for (c = 0; c < data->chip->nchans; c++) { 470 irq = irq_find_mapping(data->irq, c); 471 irq_dispose_mapping(irq); 472 } 473 irq_domain_remove(data->irq); 474 } 475 i2c_mux_del_adapters(muxc); 476 } 477 478 static int pca954x_init(struct i2c_client *client, struct pca954x *data) 479 { 480 int ret; 481 482 if (data->idle_state >= 0) 483 data->last_chan = pca954x_regval(data, data->idle_state); 484 else 485 data->last_chan = 0; /* Disconnect multiplexer */ 486 487 if (device_is_compatible(&client->dev, "maxim,max7357")) { 488 if (i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WRITE_BYTE_DATA)) { 489 u8 conf = MAX7357_POR_DEFAULT_CONF; 490 /* 491 * The interrupt signal is shared with the reset pin. Release the 492 * interrupt after 1.6 seconds to allow using the pin as reset. 493 */ 494 conf |= MAX7357_CONF_RELEASE_INT; 495 496 if (device_property_read_bool(&client->dev, "maxim,isolate-stuck-channel")) 497 conf |= MAX7357_CONF_DISCON_SINGLE_CHAN; 498 if (device_property_read_bool(&client->dev, 499 "maxim,send-flush-out-sequence")) 500 conf |= MAX7357_CONF_FLUSH_OUT; 501 if (device_property_read_bool(&client->dev, 502 "maxim,preconnection-wiggle-test-enable")) 503 conf |= MAX7357_CONF_PRECONNECT_TEST; 504 505 ret = i2c_smbus_write_byte_data(client, data->last_chan, conf); 506 } else { 507 dev_warn(&client->dev, "Write byte data not supported." 508 "Cannot enable enhanced mode features\n"); 509 ret = i2c_smbus_write_byte(client, data->last_chan); 510 } 511 } else { 512 ret = i2c_smbus_write_byte(client, data->last_chan); 513 } 514 515 if (ret < 0) 516 data->last_chan = 0; 517 518 return ret; 519 } 520 521 /* 522 * I2C init/probing/exit functions 523 */ 524 static int pca954x_probe(struct i2c_client *client) 525 { 526 const struct i2c_device_id *id = i2c_client_get_device_id(client); 527 struct i2c_adapter *adap = client->adapter; 528 struct device *dev = &client->dev; 529 struct gpio_desc *gpio; 530 struct i2c_mux_core *muxc; 531 struct pca954x *data; 532 int num; 533 int ret; 534 535 if (!i2c_check_functionality(adap, I2C_FUNC_SMBUS_BYTE)) 536 return -ENODEV; 537 538 muxc = i2c_mux_alloc(adap, dev, PCA954X_MAX_NCHANS, sizeof(*data), 0, 539 pca954x_select_chan, pca954x_deselect_mux); 540 if (!muxc) 541 return -ENOMEM; 542 data = i2c_mux_priv(muxc); 543 544 i2c_set_clientdata(client, muxc); 545 data->client = client; 546 547 data->supply = devm_regulator_get(dev, "vdd"); 548 if (IS_ERR(data->supply)) 549 return dev_err_probe(dev, PTR_ERR(data->supply), 550 "Failed to request regulator\n"); 551 552 ret = regulator_enable(data->supply); 553 if (ret) 554 return dev_err_probe(dev, ret, 555 "Failed to enable vdd supply\n"); 556 557 /* Reset the mux if a reset GPIO is specified. */ 558 gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH); 559 if (IS_ERR(gpio)) { 560 ret = PTR_ERR(gpio); 561 goto fail_cleanup; 562 } 563 if (gpio) { 564 udelay(1); 565 gpiod_set_value_cansleep(gpio, 0); 566 /* Give the chip some time to recover. */ 567 udelay(1); 568 } 569 570 data->chip = device_get_match_data(dev); 571 if (!data->chip) 572 data->chip = &chips[id->driver_data]; 573 574 if (data->chip->id.manufacturer_id != I2C_DEVICE_ID_NONE) { 575 struct i2c_device_identity id; 576 577 ret = i2c_get_device_id(client, &id); 578 if (ret && ret != -EOPNOTSUPP) 579 goto fail_cleanup; 580 581 if (!ret && 582 (id.manufacturer_id != data->chip->id.manufacturer_id || 583 id.part_id != data->chip->id.part_id)) { 584 dev_warn(dev, "unexpected device id %03x-%03x-%x\n", 585 id.manufacturer_id, id.part_id, 586 id.die_revision); 587 ret = -ENODEV; 588 goto fail_cleanup; 589 } 590 } 591 592 data->idle_state = MUX_IDLE_AS_IS; 593 if (device_property_read_u32(dev, "idle-state", &data->idle_state)) { 594 if (device_property_read_bool(dev, "i2c-mux-idle-disconnect")) 595 data->idle_state = MUX_IDLE_DISCONNECT; 596 } 597 598 /* 599 * Write the mux register at addr to verify 600 * that the mux is in fact present. This also 601 * initializes the mux to a channel 602 * or disconnected state. 603 */ 604 ret = pca954x_init(client, data); 605 if (ret < 0) { 606 dev_warn(dev, "probe failed\n"); 607 ret = -ENODEV; 608 goto fail_cleanup; 609 } 610 611 ret = pca954x_irq_setup(muxc); 612 if (ret) 613 goto fail_cleanup; 614 615 /* Now create an adapter for each channel */ 616 for (num = 0; num < data->chip->nchans; num++) { 617 ret = i2c_mux_add_adapter(muxc, 0, num, 0); 618 if (ret) 619 goto fail_cleanup; 620 } 621 622 if (data->irq) { 623 ret = devm_request_threaded_irq(dev, data->client->irq, 624 NULL, pca954x_irq_handler, 625 IRQF_ONESHOT | IRQF_SHARED, 626 "pca954x", data); 627 if (ret) 628 goto fail_cleanup; 629 } 630 631 /* 632 * The attr probably isn't going to be needed in most cases, 633 * so don't fail completely on error. 634 */ 635 device_create_file(dev, &dev_attr_idle_state); 636 637 dev_info(dev, "registered %d multiplexed busses for I2C %s %s\n", 638 num, data->chip->muxtype == pca954x_ismux 639 ? "mux" : "switch", client->name); 640 641 return 0; 642 643 fail_cleanup: 644 pca954x_cleanup(muxc); 645 return ret; 646 } 647 648 static void pca954x_remove(struct i2c_client *client) 649 { 650 struct i2c_mux_core *muxc = i2c_get_clientdata(client); 651 652 device_remove_file(&client->dev, &dev_attr_idle_state); 653 654 pca954x_cleanup(muxc); 655 } 656 657 static int pca954x_resume(struct device *dev) 658 { 659 struct i2c_client *client = to_i2c_client(dev); 660 struct i2c_mux_core *muxc = i2c_get_clientdata(client); 661 struct pca954x *data = i2c_mux_priv(muxc); 662 int ret; 663 664 ret = pca954x_init(client, data); 665 if (ret < 0) 666 dev_err(&client->dev, "failed to verify mux presence\n"); 667 668 return ret; 669 } 670 671 static DEFINE_SIMPLE_DEV_PM_OPS(pca954x_pm, NULL, pca954x_resume); 672 673 static struct i2c_driver pca954x_driver = { 674 .driver = { 675 .name = "pca954x", 676 .pm = pm_sleep_ptr(&pca954x_pm), 677 .of_match_table = pca954x_of_match, 678 }, 679 .probe = pca954x_probe, 680 .remove = pca954x_remove, 681 .id_table = pca954x_id, 682 }; 683 684 module_i2c_driver(pca954x_driver); 685 686 MODULE_AUTHOR("Rodolfo Giometti <giometti@linux.it>"); 687 MODULE_DESCRIPTION("PCA954x I2C mux/switch driver"); 688 MODULE_LICENSE("GPL v2"); 689