1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * opt3001.c - Texas Instruments OPT3001 Light Sensor 4 * 5 * Copyright (C) 2014 Texas Instruments Incorporated - https://www.ti.com 6 * 7 * Author: Andreas Dannenberg <dannenberg@ti.com> 8 * Based on previous work from: Felipe Balbi <balbi@ti.com> 9 */ 10 11 #include <linux/bitops.h> 12 #include <linux/delay.h> 13 #include <linux/device.h> 14 #include <linux/i2c.h> 15 #include <linux/interrupt.h> 16 #include <linux/irq.h> 17 #include <linux/kernel.h> 18 #include <linux/module.h> 19 #include <linux/mod_devicetable.h> 20 #include <linux/mutex.h> 21 #include <linux/slab.h> 22 #include <linux/types.h> 23 24 #include <linux/iio/events.h> 25 #include <linux/iio/iio.h> 26 #include <linux/iio/sysfs.h> 27 28 #define OPT3001_RESULT 0x00 29 #define OPT3001_CONFIGURATION 0x01 30 #define OPT3001_LOW_LIMIT 0x02 31 #define OPT3001_HIGH_LIMIT 0x03 32 #define OPT3001_MANUFACTURER_ID 0x7e 33 #define OPT3001_DEVICE_ID 0x7f 34 35 #define OPT3001_CONFIGURATION_RN_MASK (0xf << 12) 36 #define OPT3001_CONFIGURATION_RN_AUTO (0xc << 12) 37 38 #define OPT3001_CONFIGURATION_CT BIT(11) 39 40 #define OPT3001_CONFIGURATION_M_MASK (3 << 9) 41 #define OPT3001_CONFIGURATION_M_SHUTDOWN (0 << 9) 42 #define OPT3001_CONFIGURATION_M_SINGLE (1 << 9) 43 #define OPT3001_CONFIGURATION_M_CONTINUOUS (2 << 9) /* also 3 << 9 */ 44 45 #define OPT3001_CONFIGURATION_OVF BIT(8) 46 #define OPT3001_CONFIGURATION_CRF BIT(7) 47 #define OPT3001_CONFIGURATION_FH BIT(6) 48 #define OPT3001_CONFIGURATION_FL BIT(5) 49 #define OPT3001_CONFIGURATION_L BIT(4) 50 #define OPT3001_CONFIGURATION_POL BIT(3) 51 #define OPT3001_CONFIGURATION_ME BIT(2) 52 53 #define OPT3001_CONFIGURATION_FC_MASK (3 << 0) 54 55 /* The end-of-conversion enable is located in the low-limit register */ 56 #define OPT3001_LOW_LIMIT_EOC_ENABLE 0xc000 57 58 #define OPT3001_REG_EXPONENT(n) ((n) >> 12) 59 #define OPT3001_REG_MANTISSA(n) ((n) & 0xfff) 60 61 #define OPT3001_INT_TIME_LONG 800000 62 #define OPT3001_INT_TIME_SHORT 100000 63 64 /* 65 * Time to wait for conversion result to be ready. The device datasheet 66 * sect. 6.5 states results are ready after total integration time plus 3ms. 67 * This results in worst-case max values of 113ms or 883ms, respectively. 68 * Add some slack to be on the safe side. 69 */ 70 #define OPT3001_RESULT_READY_SHORT 150 71 #define OPT3001_RESULT_READY_LONG 1000 72 73 struct opt3001 { 74 struct i2c_client *client; 75 struct device *dev; 76 77 struct mutex lock; 78 bool ok_to_ignore_lock; 79 bool result_ready; 80 wait_queue_head_t result_ready_queue; 81 u16 result; 82 83 u32 int_time; 84 u32 mode; 85 86 u16 high_thresh_mantissa; 87 u16 low_thresh_mantissa; 88 89 u8 high_thresh_exp; 90 u8 low_thresh_exp; 91 92 bool use_irq; 93 }; 94 95 struct opt3001_scale { 96 int val; 97 int val2; 98 }; 99 100 static const struct opt3001_scale opt3001_scales[] = { 101 { 102 .val = 40, 103 .val2 = 950000, 104 }, 105 { 106 .val = 81, 107 .val2 = 900000, 108 }, 109 { 110 .val = 163, 111 .val2 = 800000, 112 }, 113 { 114 .val = 327, 115 .val2 = 600000, 116 }, 117 { 118 .val = 655, 119 .val2 = 200000, 120 }, 121 { 122 .val = 1310, 123 .val2 = 400000, 124 }, 125 { 126 .val = 2620, 127 .val2 = 800000, 128 }, 129 { 130 .val = 5241, 131 .val2 = 600000, 132 }, 133 { 134 .val = 10483, 135 .val2 = 200000, 136 }, 137 { 138 .val = 20966, 139 .val2 = 400000, 140 }, 141 { 142 .val = 83865, 143 .val2 = 600000, 144 }, 145 }; 146 147 static int opt3001_find_scale(const struct opt3001 *opt, int val, 148 int val2, u8 *exponent) 149 { 150 int i; 151 152 for (i = 0; i < ARRAY_SIZE(opt3001_scales); i++) { 153 const struct opt3001_scale *scale = &opt3001_scales[i]; 154 155 /* 156 * Combine the integer and micro parts for comparison 157 * purposes. Use milli lux precision to avoid 32-bit integer 158 * overflows. 159 */ 160 if ((val * 1000 + val2 / 1000) <= 161 (scale->val * 1000 + scale->val2 / 1000)) { 162 *exponent = i; 163 return 0; 164 } 165 } 166 167 return -EINVAL; 168 } 169 170 static void opt3001_to_iio_ret(struct opt3001 *opt, u8 exponent, 171 u16 mantissa, int *val, int *val2) 172 { 173 int lux; 174 175 lux = 10 * (mantissa << exponent); 176 *val = lux / 1000; 177 *val2 = (lux - (*val * 1000)) * 1000; 178 } 179 180 static void opt3001_set_mode(struct opt3001 *opt, u16 *reg, u16 mode) 181 { 182 *reg &= ~OPT3001_CONFIGURATION_M_MASK; 183 *reg |= mode; 184 opt->mode = mode; 185 } 186 187 static IIO_CONST_ATTR_INT_TIME_AVAIL("0.1 0.8"); 188 189 static struct attribute *opt3001_attributes[] = { 190 &iio_const_attr_integration_time_available.dev_attr.attr, 191 NULL 192 }; 193 194 static const struct attribute_group opt3001_attribute_group = { 195 .attrs = opt3001_attributes, 196 }; 197 198 static const struct iio_event_spec opt3001_event_spec[] = { 199 { 200 .type = IIO_EV_TYPE_THRESH, 201 .dir = IIO_EV_DIR_RISING, 202 .mask_separate = BIT(IIO_EV_INFO_VALUE) | 203 BIT(IIO_EV_INFO_ENABLE), 204 }, 205 { 206 .type = IIO_EV_TYPE_THRESH, 207 .dir = IIO_EV_DIR_FALLING, 208 .mask_separate = BIT(IIO_EV_INFO_VALUE) | 209 BIT(IIO_EV_INFO_ENABLE), 210 }, 211 }; 212 213 static const struct iio_chan_spec opt3001_channels[] = { 214 { 215 .type = IIO_LIGHT, 216 .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) | 217 BIT(IIO_CHAN_INFO_INT_TIME), 218 .event_spec = opt3001_event_spec, 219 .num_event_specs = ARRAY_SIZE(opt3001_event_spec), 220 }, 221 IIO_CHAN_SOFT_TIMESTAMP(1), 222 }; 223 224 static int opt3001_get_lux(struct opt3001 *opt, int *val, int *val2) 225 { 226 int ret; 227 u16 mantissa; 228 u16 reg; 229 u8 exponent; 230 u16 value; 231 long timeout; 232 233 if (opt->use_irq) { 234 /* 235 * Enable the end-of-conversion interrupt mechanism. Note that 236 * doing so will overwrite the low-level limit value however we 237 * will restore this value later on. 238 */ 239 ret = i2c_smbus_write_word_swapped(opt->client, 240 OPT3001_LOW_LIMIT, 241 OPT3001_LOW_LIMIT_EOC_ENABLE); 242 if (ret < 0) { 243 dev_err(opt->dev, "failed to write register %02x\n", 244 OPT3001_LOW_LIMIT); 245 return ret; 246 } 247 248 /* Allow IRQ to access the device despite lock being set */ 249 opt->ok_to_ignore_lock = true; 250 } 251 252 /* Reset data-ready indicator flag */ 253 opt->result_ready = false; 254 255 /* Configure for single-conversion mode and start a new conversion */ 256 ret = i2c_smbus_read_word_swapped(opt->client, OPT3001_CONFIGURATION); 257 if (ret < 0) { 258 dev_err(opt->dev, "failed to read register %02x\n", 259 OPT3001_CONFIGURATION); 260 goto err; 261 } 262 263 reg = ret; 264 opt3001_set_mode(opt, ®, OPT3001_CONFIGURATION_M_SINGLE); 265 266 ret = i2c_smbus_write_word_swapped(opt->client, OPT3001_CONFIGURATION, 267 reg); 268 if (ret < 0) { 269 dev_err(opt->dev, "failed to write register %02x\n", 270 OPT3001_CONFIGURATION); 271 goto err; 272 } 273 274 if (opt->use_irq) { 275 /* Wait for the IRQ to indicate the conversion is complete */ 276 ret = wait_event_timeout(opt->result_ready_queue, 277 opt->result_ready, 278 msecs_to_jiffies(OPT3001_RESULT_READY_LONG)); 279 if (ret == 0) 280 return -ETIMEDOUT; 281 } else { 282 /* Sleep for result ready time */ 283 timeout = (opt->int_time == OPT3001_INT_TIME_SHORT) ? 284 OPT3001_RESULT_READY_SHORT : OPT3001_RESULT_READY_LONG; 285 msleep(timeout); 286 287 /* Check result ready flag */ 288 ret = i2c_smbus_read_word_swapped(opt->client, 289 OPT3001_CONFIGURATION); 290 if (ret < 0) { 291 dev_err(opt->dev, "failed to read register %02x\n", 292 OPT3001_CONFIGURATION); 293 goto err; 294 } 295 296 if (!(ret & OPT3001_CONFIGURATION_CRF)) { 297 ret = -ETIMEDOUT; 298 goto err; 299 } 300 301 /* Obtain value */ 302 ret = i2c_smbus_read_word_swapped(opt->client, OPT3001_RESULT); 303 if (ret < 0) { 304 dev_err(opt->dev, "failed to read register %02x\n", 305 OPT3001_RESULT); 306 goto err; 307 } 308 opt->result = ret; 309 opt->result_ready = true; 310 } 311 312 err: 313 if (opt->use_irq) 314 /* Disallow IRQ to access the device while lock is active */ 315 opt->ok_to_ignore_lock = false; 316 317 if (ret < 0) 318 return ret; 319 320 if (opt->use_irq) { 321 /* 322 * Disable the end-of-conversion interrupt mechanism by 323 * restoring the low-level limit value (clearing 324 * OPT3001_LOW_LIMIT_EOC_ENABLE). Note that selectively clearing 325 * those enable bits would affect the actual limit value due to 326 * bit-overlap and therefore can't be done. 327 */ 328 value = (opt->low_thresh_exp << 12) | opt->low_thresh_mantissa; 329 ret = i2c_smbus_write_word_swapped(opt->client, 330 OPT3001_LOW_LIMIT, 331 value); 332 if (ret < 0) { 333 dev_err(opt->dev, "failed to write register %02x\n", 334 OPT3001_LOW_LIMIT); 335 return ret; 336 } 337 } 338 339 exponent = OPT3001_REG_EXPONENT(opt->result); 340 mantissa = OPT3001_REG_MANTISSA(opt->result); 341 342 opt3001_to_iio_ret(opt, exponent, mantissa, val, val2); 343 344 return IIO_VAL_INT_PLUS_MICRO; 345 } 346 347 static int opt3001_get_int_time(struct opt3001 *opt, int *val, int *val2) 348 { 349 *val = 0; 350 *val2 = opt->int_time; 351 352 return IIO_VAL_INT_PLUS_MICRO; 353 } 354 355 static int opt3001_set_int_time(struct opt3001 *opt, int time) 356 { 357 int ret; 358 u16 reg; 359 360 ret = i2c_smbus_read_word_swapped(opt->client, OPT3001_CONFIGURATION); 361 if (ret < 0) { 362 dev_err(opt->dev, "failed to read register %02x\n", 363 OPT3001_CONFIGURATION); 364 return ret; 365 } 366 367 reg = ret; 368 369 switch (time) { 370 case OPT3001_INT_TIME_SHORT: 371 reg &= ~OPT3001_CONFIGURATION_CT; 372 opt->int_time = OPT3001_INT_TIME_SHORT; 373 break; 374 case OPT3001_INT_TIME_LONG: 375 reg |= OPT3001_CONFIGURATION_CT; 376 opt->int_time = OPT3001_INT_TIME_LONG; 377 break; 378 default: 379 return -EINVAL; 380 } 381 382 return i2c_smbus_write_word_swapped(opt->client, OPT3001_CONFIGURATION, 383 reg); 384 } 385 386 static int opt3001_read_raw(struct iio_dev *iio, 387 struct iio_chan_spec const *chan, int *val, int *val2, 388 long mask) 389 { 390 struct opt3001 *opt = iio_priv(iio); 391 int ret; 392 393 if (opt->mode == OPT3001_CONFIGURATION_M_CONTINUOUS) 394 return -EBUSY; 395 396 if (chan->type != IIO_LIGHT) 397 return -EINVAL; 398 399 mutex_lock(&opt->lock); 400 401 switch (mask) { 402 case IIO_CHAN_INFO_PROCESSED: 403 ret = opt3001_get_lux(opt, val, val2); 404 break; 405 case IIO_CHAN_INFO_INT_TIME: 406 ret = opt3001_get_int_time(opt, val, val2); 407 break; 408 default: 409 ret = -EINVAL; 410 } 411 412 mutex_unlock(&opt->lock); 413 414 return ret; 415 } 416 417 static int opt3001_write_raw(struct iio_dev *iio, 418 struct iio_chan_spec const *chan, int val, int val2, 419 long mask) 420 { 421 struct opt3001 *opt = iio_priv(iio); 422 int ret; 423 424 if (opt->mode == OPT3001_CONFIGURATION_M_CONTINUOUS) 425 return -EBUSY; 426 427 if (chan->type != IIO_LIGHT) 428 return -EINVAL; 429 430 if (mask != IIO_CHAN_INFO_INT_TIME) 431 return -EINVAL; 432 433 if (val != 0) 434 return -EINVAL; 435 436 mutex_lock(&opt->lock); 437 ret = opt3001_set_int_time(opt, val2); 438 mutex_unlock(&opt->lock); 439 440 return ret; 441 } 442 443 static int opt3001_read_event_value(struct iio_dev *iio, 444 const struct iio_chan_spec *chan, enum iio_event_type type, 445 enum iio_event_direction dir, enum iio_event_info info, 446 int *val, int *val2) 447 { 448 struct opt3001 *opt = iio_priv(iio); 449 int ret = IIO_VAL_INT_PLUS_MICRO; 450 451 mutex_lock(&opt->lock); 452 453 switch (dir) { 454 case IIO_EV_DIR_RISING: 455 opt3001_to_iio_ret(opt, opt->high_thresh_exp, 456 opt->high_thresh_mantissa, val, val2); 457 break; 458 case IIO_EV_DIR_FALLING: 459 opt3001_to_iio_ret(opt, opt->low_thresh_exp, 460 opt->low_thresh_mantissa, val, val2); 461 break; 462 default: 463 ret = -EINVAL; 464 } 465 466 mutex_unlock(&opt->lock); 467 468 return ret; 469 } 470 471 static int opt3001_write_event_value(struct iio_dev *iio, 472 const struct iio_chan_spec *chan, enum iio_event_type type, 473 enum iio_event_direction dir, enum iio_event_info info, 474 int val, int val2) 475 { 476 struct opt3001 *opt = iio_priv(iio); 477 int ret; 478 479 u16 mantissa; 480 u16 value; 481 u16 reg; 482 483 u8 exponent; 484 485 if (val < 0) 486 return -EINVAL; 487 488 mutex_lock(&opt->lock); 489 490 ret = opt3001_find_scale(opt, val, val2, &exponent); 491 if (ret < 0) { 492 dev_err(opt->dev, "can't find scale for %d.%06u\n", val, val2); 493 goto err; 494 } 495 496 mantissa = (((val * 1000) + (val2 / 1000)) / 10) >> exponent; 497 value = (exponent << 12) | mantissa; 498 499 switch (dir) { 500 case IIO_EV_DIR_RISING: 501 reg = OPT3001_HIGH_LIMIT; 502 opt->high_thresh_mantissa = mantissa; 503 opt->high_thresh_exp = exponent; 504 break; 505 case IIO_EV_DIR_FALLING: 506 reg = OPT3001_LOW_LIMIT; 507 opt->low_thresh_mantissa = mantissa; 508 opt->low_thresh_exp = exponent; 509 break; 510 default: 511 ret = -EINVAL; 512 goto err; 513 } 514 515 ret = i2c_smbus_write_word_swapped(opt->client, reg, value); 516 if (ret < 0) { 517 dev_err(opt->dev, "failed to write register %02x\n", reg); 518 goto err; 519 } 520 521 err: 522 mutex_unlock(&opt->lock); 523 524 return ret; 525 } 526 527 static int opt3001_read_event_config(struct iio_dev *iio, 528 const struct iio_chan_spec *chan, enum iio_event_type type, 529 enum iio_event_direction dir) 530 { 531 struct opt3001 *opt = iio_priv(iio); 532 533 return opt->mode == OPT3001_CONFIGURATION_M_CONTINUOUS; 534 } 535 536 static int opt3001_write_event_config(struct iio_dev *iio, 537 const struct iio_chan_spec *chan, enum iio_event_type type, 538 enum iio_event_direction dir, int state) 539 { 540 struct opt3001 *opt = iio_priv(iio); 541 int ret; 542 u16 mode; 543 u16 reg; 544 545 if (state && opt->mode == OPT3001_CONFIGURATION_M_CONTINUOUS) 546 return 0; 547 548 if (!state && opt->mode == OPT3001_CONFIGURATION_M_SHUTDOWN) 549 return 0; 550 551 mutex_lock(&opt->lock); 552 553 mode = state ? OPT3001_CONFIGURATION_M_CONTINUOUS 554 : OPT3001_CONFIGURATION_M_SHUTDOWN; 555 556 ret = i2c_smbus_read_word_swapped(opt->client, OPT3001_CONFIGURATION); 557 if (ret < 0) { 558 dev_err(opt->dev, "failed to read register %02x\n", 559 OPT3001_CONFIGURATION); 560 goto err; 561 } 562 563 reg = ret; 564 opt3001_set_mode(opt, ®, mode); 565 566 ret = i2c_smbus_write_word_swapped(opt->client, OPT3001_CONFIGURATION, 567 reg); 568 if (ret < 0) { 569 dev_err(opt->dev, "failed to write register %02x\n", 570 OPT3001_CONFIGURATION); 571 goto err; 572 } 573 574 err: 575 mutex_unlock(&opt->lock); 576 577 return ret; 578 } 579 580 static const struct iio_info opt3001_info = { 581 .attrs = &opt3001_attribute_group, 582 .read_raw = opt3001_read_raw, 583 .write_raw = opt3001_write_raw, 584 .read_event_value = opt3001_read_event_value, 585 .write_event_value = opt3001_write_event_value, 586 .read_event_config = opt3001_read_event_config, 587 .write_event_config = opt3001_write_event_config, 588 }; 589 590 static int opt3001_read_id(struct opt3001 *opt) 591 { 592 char manufacturer[2]; 593 u16 device_id; 594 int ret; 595 596 ret = i2c_smbus_read_word_swapped(opt->client, OPT3001_MANUFACTURER_ID); 597 if (ret < 0) { 598 dev_err(opt->dev, "failed to read register %02x\n", 599 OPT3001_MANUFACTURER_ID); 600 return ret; 601 } 602 603 manufacturer[0] = ret >> 8; 604 manufacturer[1] = ret & 0xff; 605 606 ret = i2c_smbus_read_word_swapped(opt->client, OPT3001_DEVICE_ID); 607 if (ret < 0) { 608 dev_err(opt->dev, "failed to read register %02x\n", 609 OPT3001_DEVICE_ID); 610 return ret; 611 } 612 613 device_id = ret; 614 615 dev_info(opt->dev, "Found %c%c OPT%04x\n", manufacturer[0], 616 manufacturer[1], device_id); 617 618 return 0; 619 } 620 621 static int opt3001_configure(struct opt3001 *opt) 622 { 623 int ret; 624 u16 reg; 625 626 ret = i2c_smbus_read_word_swapped(opt->client, OPT3001_CONFIGURATION); 627 if (ret < 0) { 628 dev_err(opt->dev, "failed to read register %02x\n", 629 OPT3001_CONFIGURATION); 630 return ret; 631 } 632 633 reg = ret; 634 635 /* Enable automatic full-scale setting mode */ 636 reg &= ~OPT3001_CONFIGURATION_RN_MASK; 637 reg |= OPT3001_CONFIGURATION_RN_AUTO; 638 639 /* Reflect status of the device's integration time setting */ 640 if (reg & OPT3001_CONFIGURATION_CT) 641 opt->int_time = OPT3001_INT_TIME_LONG; 642 else 643 opt->int_time = OPT3001_INT_TIME_SHORT; 644 645 /* Ensure device is in shutdown initially */ 646 opt3001_set_mode(opt, ®, OPT3001_CONFIGURATION_M_SHUTDOWN); 647 648 /* Configure for latched window-style comparison operation */ 649 reg |= OPT3001_CONFIGURATION_L; 650 reg &= ~OPT3001_CONFIGURATION_POL; 651 reg &= ~OPT3001_CONFIGURATION_ME; 652 reg &= ~OPT3001_CONFIGURATION_FC_MASK; 653 654 ret = i2c_smbus_write_word_swapped(opt->client, OPT3001_CONFIGURATION, 655 reg); 656 if (ret < 0) { 657 dev_err(opt->dev, "failed to write register %02x\n", 658 OPT3001_CONFIGURATION); 659 return ret; 660 } 661 662 ret = i2c_smbus_read_word_swapped(opt->client, OPT3001_LOW_LIMIT); 663 if (ret < 0) { 664 dev_err(opt->dev, "failed to read register %02x\n", 665 OPT3001_LOW_LIMIT); 666 return ret; 667 } 668 669 opt->low_thresh_mantissa = OPT3001_REG_MANTISSA(ret); 670 opt->low_thresh_exp = OPT3001_REG_EXPONENT(ret); 671 672 ret = i2c_smbus_read_word_swapped(opt->client, OPT3001_HIGH_LIMIT); 673 if (ret < 0) { 674 dev_err(opt->dev, "failed to read register %02x\n", 675 OPT3001_HIGH_LIMIT); 676 return ret; 677 } 678 679 opt->high_thresh_mantissa = OPT3001_REG_MANTISSA(ret); 680 opt->high_thresh_exp = OPT3001_REG_EXPONENT(ret); 681 682 return 0; 683 } 684 685 static irqreturn_t opt3001_irq(int irq, void *_iio) 686 { 687 struct iio_dev *iio = _iio; 688 struct opt3001 *opt = iio_priv(iio); 689 int ret; 690 bool wake_result_ready_queue = false; 691 692 if (!opt->ok_to_ignore_lock) 693 mutex_lock(&opt->lock); 694 695 ret = i2c_smbus_read_word_swapped(opt->client, OPT3001_CONFIGURATION); 696 if (ret < 0) { 697 dev_err(opt->dev, "failed to read register %02x\n", 698 OPT3001_CONFIGURATION); 699 goto out; 700 } 701 702 if ((ret & OPT3001_CONFIGURATION_M_MASK) == 703 OPT3001_CONFIGURATION_M_CONTINUOUS) { 704 if (ret & OPT3001_CONFIGURATION_FH) 705 iio_push_event(iio, 706 IIO_UNMOD_EVENT_CODE(IIO_LIGHT, 0, 707 IIO_EV_TYPE_THRESH, 708 IIO_EV_DIR_RISING), 709 iio_get_time_ns(iio)); 710 if (ret & OPT3001_CONFIGURATION_FL) 711 iio_push_event(iio, 712 IIO_UNMOD_EVENT_CODE(IIO_LIGHT, 0, 713 IIO_EV_TYPE_THRESH, 714 IIO_EV_DIR_FALLING), 715 iio_get_time_ns(iio)); 716 } else if (ret & OPT3001_CONFIGURATION_CRF) { 717 ret = i2c_smbus_read_word_swapped(opt->client, OPT3001_RESULT); 718 if (ret < 0) { 719 dev_err(opt->dev, "failed to read register %02x\n", 720 OPT3001_RESULT); 721 goto out; 722 } 723 opt->result = ret; 724 opt->result_ready = true; 725 wake_result_ready_queue = true; 726 } 727 728 out: 729 if (!opt->ok_to_ignore_lock) 730 mutex_unlock(&opt->lock); 731 732 if (wake_result_ready_queue) 733 wake_up(&opt->result_ready_queue); 734 735 return IRQ_HANDLED; 736 } 737 738 static int opt3001_probe(struct i2c_client *client) 739 { 740 struct device *dev = &client->dev; 741 742 struct iio_dev *iio; 743 struct opt3001 *opt; 744 int irq = client->irq; 745 int ret; 746 747 iio = devm_iio_device_alloc(dev, sizeof(*opt)); 748 if (!iio) 749 return -ENOMEM; 750 751 opt = iio_priv(iio); 752 opt->client = client; 753 opt->dev = dev; 754 755 mutex_init(&opt->lock); 756 init_waitqueue_head(&opt->result_ready_queue); 757 i2c_set_clientdata(client, iio); 758 759 ret = opt3001_read_id(opt); 760 if (ret) 761 return ret; 762 763 ret = opt3001_configure(opt); 764 if (ret) 765 return ret; 766 767 iio->name = client->name; 768 iio->channels = opt3001_channels; 769 iio->num_channels = ARRAY_SIZE(opt3001_channels); 770 iio->modes = INDIO_DIRECT_MODE; 771 iio->info = &opt3001_info; 772 773 ret = devm_iio_device_register(dev, iio); 774 if (ret) { 775 dev_err(dev, "failed to register IIO device\n"); 776 return ret; 777 } 778 779 /* Make use of INT pin only if valid IRQ no. is given */ 780 if (irq > 0) { 781 ret = request_threaded_irq(irq, NULL, opt3001_irq, 782 IRQF_TRIGGER_FALLING | IRQF_ONESHOT, 783 "opt3001", iio); 784 if (ret) { 785 dev_err(dev, "failed to request IRQ #%d\n", irq); 786 return ret; 787 } 788 opt->use_irq = true; 789 } else { 790 dev_dbg(opt->dev, "enabling interrupt-less operation\n"); 791 } 792 793 return 0; 794 } 795 796 static void opt3001_remove(struct i2c_client *client) 797 { 798 struct iio_dev *iio = i2c_get_clientdata(client); 799 struct opt3001 *opt = iio_priv(iio); 800 int ret; 801 u16 reg; 802 803 if (opt->use_irq) 804 free_irq(client->irq, iio); 805 806 ret = i2c_smbus_read_word_swapped(opt->client, OPT3001_CONFIGURATION); 807 if (ret < 0) { 808 dev_err(opt->dev, "failed to read register %02x\n", 809 OPT3001_CONFIGURATION); 810 return; 811 } 812 813 reg = ret; 814 opt3001_set_mode(opt, ®, OPT3001_CONFIGURATION_M_SHUTDOWN); 815 816 ret = i2c_smbus_write_word_swapped(opt->client, OPT3001_CONFIGURATION, 817 reg); 818 if (ret < 0) { 819 dev_err(opt->dev, "failed to write register %02x\n", 820 OPT3001_CONFIGURATION); 821 } 822 } 823 824 static const struct i2c_device_id opt3001_id[] = { 825 { "opt3001" }, 826 { } /* Terminating Entry */ 827 }; 828 MODULE_DEVICE_TABLE(i2c, opt3001_id); 829 830 static const struct of_device_id opt3001_of_match[] = { 831 { .compatible = "ti,opt3001" }, 832 { } 833 }; 834 MODULE_DEVICE_TABLE(of, opt3001_of_match); 835 836 static struct i2c_driver opt3001_driver = { 837 .probe = opt3001_probe, 838 .remove = opt3001_remove, 839 .id_table = opt3001_id, 840 841 .driver = { 842 .name = "opt3001", 843 .of_match_table = opt3001_of_match, 844 }, 845 }; 846 847 module_i2c_driver(opt3001_driver); 848 849 MODULE_LICENSE("GPL v2"); 850 MODULE_AUTHOR("Andreas Dannenberg <dannenberg@ti.com>"); 851 MODULE_DESCRIPTION("Texas Instruments OPT3001 Light Sensor Driver"); 852