1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * tcs3472.c - Support for TAOS TCS3472 color light-to-digital converter 4 * 5 * Copyright (c) 2013 Peter Meerwald <pmeerw@pmeerw.net> 6 * 7 * Color light sensor with 16-bit channels for red, green, blue, clear); 8 * 7-bit I2C slave address 0x39 (TCS34721, TCS34723) or 0x29 (TCS34725, 9 * TCS34727) 10 * 11 * Datasheet: http://ams.com/eng/content/download/319364/1117183/file/TCS3472_Datasheet_EN_v2.pdf 12 * 13 * TODO: wait time 14 */ 15 16 #include <linux/module.h> 17 #include <linux/i2c.h> 18 #include <linux/delay.h> 19 #include <linux/pm.h> 20 21 #include <linux/iio/iio.h> 22 #include <linux/iio/sysfs.h> 23 #include <linux/iio/events.h> 24 #include <linux/iio/trigger_consumer.h> 25 #include <linux/iio/buffer.h> 26 #include <linux/iio/triggered_buffer.h> 27 28 #define TCS3472_DRV_NAME "tcs3472" 29 30 #define TCS3472_COMMAND BIT(7) 31 #define TCS3472_AUTO_INCR BIT(5) 32 #define TCS3472_SPECIAL_FUNC (BIT(5) | BIT(6)) 33 34 #define TCS3472_INTR_CLEAR (TCS3472_COMMAND | TCS3472_SPECIAL_FUNC | 0x06) 35 36 #define TCS3472_ENABLE (TCS3472_COMMAND | 0x00) 37 #define TCS3472_ATIME (TCS3472_COMMAND | 0x01) 38 #define TCS3472_WTIME (TCS3472_COMMAND | 0x03) 39 #define TCS3472_AILT (TCS3472_COMMAND | TCS3472_AUTO_INCR | 0x04) 40 #define TCS3472_AIHT (TCS3472_COMMAND | TCS3472_AUTO_INCR | 0x06) 41 #define TCS3472_PERS (TCS3472_COMMAND | 0x0c) 42 #define TCS3472_CONFIG (TCS3472_COMMAND | 0x0d) 43 #define TCS3472_CONTROL (TCS3472_COMMAND | 0x0f) 44 #define TCS3472_ID (TCS3472_COMMAND | 0x12) 45 #define TCS3472_STATUS (TCS3472_COMMAND | 0x13) 46 #define TCS3472_CDATA (TCS3472_COMMAND | TCS3472_AUTO_INCR | 0x14) 47 #define TCS3472_RDATA (TCS3472_COMMAND | TCS3472_AUTO_INCR | 0x16) 48 #define TCS3472_GDATA (TCS3472_COMMAND | TCS3472_AUTO_INCR | 0x18) 49 #define TCS3472_BDATA (TCS3472_COMMAND | TCS3472_AUTO_INCR | 0x1a) 50 51 #define TCS3472_STATUS_AINT BIT(4) 52 #define TCS3472_STATUS_AVALID BIT(0) 53 #define TCS3472_ENABLE_AIEN BIT(4) 54 #define TCS3472_ENABLE_AEN BIT(1) 55 #define TCS3472_ENABLE_PON BIT(0) 56 #define TCS3472_CONTROL_AGAIN_MASK (BIT(0) | BIT(1)) 57 58 struct tcs3472_data { 59 struct i2c_client *client; 60 struct mutex lock; 61 u16 low_thresh; 62 u16 high_thresh; 63 u8 enable; 64 u8 control; 65 u8 atime; 66 u8 apers; 67 /* Ensure timestamp is naturally aligned */ 68 struct { 69 u16 chans[4]; 70 aligned_s64 timestamp; 71 } scan; 72 }; 73 74 static const struct iio_event_spec tcs3472_events[] = { 75 { 76 .type = IIO_EV_TYPE_THRESH, 77 .dir = IIO_EV_DIR_RISING, 78 .mask_separate = BIT(IIO_EV_INFO_VALUE), 79 }, { 80 .type = IIO_EV_TYPE_THRESH, 81 .dir = IIO_EV_DIR_FALLING, 82 .mask_separate = BIT(IIO_EV_INFO_VALUE), 83 }, { 84 .type = IIO_EV_TYPE_THRESH, 85 .dir = IIO_EV_DIR_EITHER, 86 .mask_separate = BIT(IIO_EV_INFO_ENABLE) | 87 BIT(IIO_EV_INFO_PERIOD), 88 }, 89 }; 90 91 #define TCS3472_CHANNEL(_color, _si, _addr) { \ 92 .type = IIO_INTENSITY, \ 93 .modified = 1, \ 94 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ 95 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_CALIBSCALE) | \ 96 BIT(IIO_CHAN_INFO_INT_TIME), \ 97 .channel2 = IIO_MOD_LIGHT_##_color, \ 98 .address = _addr, \ 99 .scan_index = _si, \ 100 .scan_type = { \ 101 .sign = 'u', \ 102 .realbits = 16, \ 103 .storagebits = 16, \ 104 .endianness = IIO_CPU, \ 105 }, \ 106 .event_spec = _si ? NULL : tcs3472_events, \ 107 .num_event_specs = _si ? 0 : ARRAY_SIZE(tcs3472_events), \ 108 } 109 110 static const int tcs3472_agains[] = { 1, 4, 16, 60 }; 111 112 static const struct iio_chan_spec tcs3472_channels[] = { 113 TCS3472_CHANNEL(CLEAR, 0, TCS3472_CDATA), 114 TCS3472_CHANNEL(RED, 1, TCS3472_RDATA), 115 TCS3472_CHANNEL(GREEN, 2, TCS3472_GDATA), 116 TCS3472_CHANNEL(BLUE, 3, TCS3472_BDATA), 117 IIO_CHAN_SOFT_TIMESTAMP(4), 118 }; 119 120 static int tcs3472_req_data(struct tcs3472_data *data) 121 { 122 int tries = 50; 123 int ret; 124 125 while (tries--) { 126 ret = i2c_smbus_read_byte_data(data->client, TCS3472_STATUS); 127 if (ret < 0) 128 return ret; 129 if (ret & TCS3472_STATUS_AVALID) 130 break; 131 msleep(20); 132 } 133 134 if (tries < 0) { 135 dev_err(&data->client->dev, "data not ready\n"); 136 return -EIO; 137 } 138 139 return 0; 140 } 141 142 static int tcs3472_read_raw(struct iio_dev *indio_dev, 143 struct iio_chan_spec const *chan, 144 int *val, int *val2, long mask) 145 { 146 struct tcs3472_data *data = iio_priv(indio_dev); 147 int ret; 148 149 switch (mask) { 150 case IIO_CHAN_INFO_RAW: 151 if (!iio_device_claim_direct(indio_dev)) 152 return -EBUSY; 153 ret = tcs3472_req_data(data); 154 if (ret < 0) { 155 iio_device_release_direct(indio_dev); 156 return ret; 157 } 158 ret = i2c_smbus_read_word_data(data->client, chan->address); 159 iio_device_release_direct(indio_dev); 160 if (ret < 0) 161 return ret; 162 *val = ret; 163 return IIO_VAL_INT; 164 case IIO_CHAN_INFO_CALIBSCALE: 165 *val = tcs3472_agains[data->control & 166 TCS3472_CONTROL_AGAIN_MASK]; 167 return IIO_VAL_INT; 168 case IIO_CHAN_INFO_INT_TIME: 169 *val = 0; 170 *val2 = (256 - data->atime) * 2400; 171 return IIO_VAL_INT_PLUS_MICRO; 172 } 173 return -EINVAL; 174 } 175 176 static int tcs3472_write_raw(struct iio_dev *indio_dev, 177 struct iio_chan_spec const *chan, 178 int val, int val2, long mask) 179 { 180 struct tcs3472_data *data = iio_priv(indio_dev); 181 int i; 182 183 switch (mask) { 184 case IIO_CHAN_INFO_CALIBSCALE: 185 if (val2 != 0) 186 return -EINVAL; 187 for (i = 0; i < ARRAY_SIZE(tcs3472_agains); i++) { 188 if (val == tcs3472_agains[i]) { 189 data->control &= ~TCS3472_CONTROL_AGAIN_MASK; 190 data->control |= i; 191 return i2c_smbus_write_byte_data( 192 data->client, TCS3472_CONTROL, 193 data->control); 194 } 195 } 196 return -EINVAL; 197 case IIO_CHAN_INFO_INT_TIME: 198 if (val != 0) 199 return -EINVAL; 200 for (i = 0; i < 256; i++) { 201 if (val2 == (256 - i) * 2400) { 202 data->atime = i; 203 return i2c_smbus_write_byte_data( 204 data->client, TCS3472_ATIME, 205 data->atime); 206 } 207 208 } 209 return -EINVAL; 210 } 211 return -EINVAL; 212 } 213 214 /* 215 * Translation from APERS field value to the number of consecutive out-of-range 216 * clear channel values before an interrupt is generated 217 */ 218 static const int tcs3472_intr_pers[] = { 219 0, 1, 2, 3, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60 220 }; 221 222 static int tcs3472_read_event(struct iio_dev *indio_dev, 223 const struct iio_chan_spec *chan, enum iio_event_type type, 224 enum iio_event_direction dir, enum iio_event_info info, int *val, 225 int *val2) 226 { 227 struct tcs3472_data *data = iio_priv(indio_dev); 228 int ret; 229 unsigned int period; 230 231 mutex_lock(&data->lock); 232 233 switch (info) { 234 case IIO_EV_INFO_VALUE: 235 *val = (dir == IIO_EV_DIR_RISING) ? 236 data->high_thresh : data->low_thresh; 237 ret = IIO_VAL_INT; 238 break; 239 case IIO_EV_INFO_PERIOD: 240 period = (256 - data->atime) * 2400 * 241 tcs3472_intr_pers[data->apers]; 242 *val = period / USEC_PER_SEC; 243 *val2 = period % USEC_PER_SEC; 244 ret = IIO_VAL_INT_PLUS_MICRO; 245 break; 246 default: 247 ret = -EINVAL; 248 break; 249 } 250 251 mutex_unlock(&data->lock); 252 253 return ret; 254 } 255 256 static int tcs3472_write_event(struct iio_dev *indio_dev, 257 const struct iio_chan_spec *chan, enum iio_event_type type, 258 enum iio_event_direction dir, enum iio_event_info info, int val, 259 int val2) 260 { 261 struct tcs3472_data *data = iio_priv(indio_dev); 262 int ret; 263 u8 command; 264 int period; 265 int i; 266 267 mutex_lock(&data->lock); 268 switch (info) { 269 case IIO_EV_INFO_VALUE: 270 switch (dir) { 271 case IIO_EV_DIR_RISING: 272 command = TCS3472_AIHT; 273 break; 274 case IIO_EV_DIR_FALLING: 275 command = TCS3472_AILT; 276 break; 277 default: 278 ret = -EINVAL; 279 goto error; 280 } 281 ret = i2c_smbus_write_word_data(data->client, command, val); 282 if (ret) 283 goto error; 284 285 if (dir == IIO_EV_DIR_RISING) 286 data->high_thresh = val; 287 else 288 data->low_thresh = val; 289 break; 290 case IIO_EV_INFO_PERIOD: 291 period = val * USEC_PER_SEC + val2; 292 for (i = 1; i < ARRAY_SIZE(tcs3472_intr_pers) - 1; i++) { 293 if (period <= (256 - data->atime) * 2400 * 294 tcs3472_intr_pers[i]) 295 break; 296 } 297 ret = i2c_smbus_write_byte_data(data->client, TCS3472_PERS, i); 298 if (ret) 299 goto error; 300 301 data->apers = i; 302 break; 303 default: 304 ret = -EINVAL; 305 break; 306 } 307 error: 308 mutex_unlock(&data->lock); 309 310 return ret; 311 } 312 313 static int tcs3472_read_event_config(struct iio_dev *indio_dev, 314 const struct iio_chan_spec *chan, enum iio_event_type type, 315 enum iio_event_direction dir) 316 { 317 struct tcs3472_data *data = iio_priv(indio_dev); 318 int ret; 319 320 mutex_lock(&data->lock); 321 ret = !!(data->enable & TCS3472_ENABLE_AIEN); 322 mutex_unlock(&data->lock); 323 324 return ret; 325 } 326 327 static int tcs3472_write_event_config(struct iio_dev *indio_dev, 328 const struct iio_chan_spec *chan, enum iio_event_type type, 329 enum iio_event_direction dir, bool state) 330 { 331 struct tcs3472_data *data = iio_priv(indio_dev); 332 int ret = 0; 333 u8 enable_old; 334 335 mutex_lock(&data->lock); 336 337 enable_old = data->enable; 338 339 if (state) 340 data->enable |= TCS3472_ENABLE_AIEN; 341 else 342 data->enable &= ~TCS3472_ENABLE_AIEN; 343 344 if (enable_old != data->enable) { 345 ret = i2c_smbus_write_byte_data(data->client, TCS3472_ENABLE, 346 data->enable); 347 if (ret) 348 data->enable = enable_old; 349 } 350 mutex_unlock(&data->lock); 351 352 return ret; 353 } 354 355 static irqreturn_t tcs3472_event_handler(int irq, void *priv) 356 { 357 struct iio_dev *indio_dev = priv; 358 struct tcs3472_data *data = iio_priv(indio_dev); 359 int ret; 360 361 ret = i2c_smbus_read_byte_data(data->client, TCS3472_STATUS); 362 if (ret >= 0 && (ret & TCS3472_STATUS_AINT)) { 363 iio_push_event(indio_dev, IIO_UNMOD_EVENT_CODE(IIO_INTENSITY, 0, 364 IIO_EV_TYPE_THRESH, 365 IIO_EV_DIR_EITHER), 366 iio_get_time_ns(indio_dev)); 367 368 i2c_smbus_read_byte_data(data->client, TCS3472_INTR_CLEAR); 369 } 370 371 return IRQ_HANDLED; 372 } 373 374 static irqreturn_t tcs3472_trigger_handler(int irq, void *p) 375 { 376 struct iio_poll_func *pf = p; 377 struct iio_dev *indio_dev = pf->indio_dev; 378 struct tcs3472_data *data = iio_priv(indio_dev); 379 int i, j = 0; 380 381 int ret = tcs3472_req_data(data); 382 if (ret < 0) 383 goto done; 384 385 iio_for_each_active_channel(indio_dev, i) { 386 ret = i2c_smbus_read_word_data(data->client, 387 TCS3472_CDATA + 2*i); 388 if (ret < 0) 389 goto done; 390 391 data->scan.chans[j++] = ret; 392 } 393 394 iio_push_to_buffers_with_timestamp(indio_dev, &data->scan, 395 iio_get_time_ns(indio_dev)); 396 397 done: 398 iio_trigger_notify_done(indio_dev->trig); 399 400 return IRQ_HANDLED; 401 } 402 403 static ssize_t tcs3472_show_int_time_available(struct device *dev, 404 struct device_attribute *attr, 405 char *buf) 406 { 407 size_t len = 0; 408 int i; 409 410 for (i = 1; i <= 256; i++) 411 len += scnprintf(buf + len, PAGE_SIZE - len, "0.%06d ", 412 2400 * i); 413 414 /* replace trailing space by newline */ 415 buf[len - 1] = '\n'; 416 417 return len; 418 } 419 420 static IIO_CONST_ATTR(calibscale_available, "1 4 16 60"); 421 static IIO_DEV_ATTR_INT_TIME_AVAIL(tcs3472_show_int_time_available); 422 423 static struct attribute *tcs3472_attributes[] = { 424 &iio_const_attr_calibscale_available.dev_attr.attr, 425 &iio_dev_attr_integration_time_available.dev_attr.attr, 426 NULL 427 }; 428 429 static const struct attribute_group tcs3472_attribute_group = { 430 .attrs = tcs3472_attributes, 431 }; 432 433 static const struct iio_info tcs3472_info = { 434 .read_raw = tcs3472_read_raw, 435 .write_raw = tcs3472_write_raw, 436 .read_event_value = tcs3472_read_event, 437 .write_event_value = tcs3472_write_event, 438 .read_event_config = tcs3472_read_event_config, 439 .write_event_config = tcs3472_write_event_config, 440 .attrs = &tcs3472_attribute_group, 441 }; 442 443 static int tcs3472_probe(struct i2c_client *client) 444 { 445 struct tcs3472_data *data; 446 struct iio_dev *indio_dev; 447 int ret; 448 449 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data)); 450 if (indio_dev == NULL) 451 return -ENOMEM; 452 453 data = iio_priv(indio_dev); 454 i2c_set_clientdata(client, indio_dev); 455 data->client = client; 456 mutex_init(&data->lock); 457 458 indio_dev->info = &tcs3472_info; 459 indio_dev->name = TCS3472_DRV_NAME; 460 indio_dev->channels = tcs3472_channels; 461 indio_dev->num_channels = ARRAY_SIZE(tcs3472_channels); 462 indio_dev->modes = INDIO_DIRECT_MODE; 463 464 ret = i2c_smbus_read_byte_data(data->client, TCS3472_ID); 465 if (ret < 0) 466 return ret; 467 468 if (ret == 0x44) 469 dev_info(&client->dev, "TCS34721/34725 found\n"); 470 else if (ret == 0x4d) 471 dev_info(&client->dev, "TCS34723/34727 found\n"); 472 else 473 return -ENODEV; 474 475 ret = i2c_smbus_read_byte_data(data->client, TCS3472_CONTROL); 476 if (ret < 0) 477 return ret; 478 data->control = ret; 479 480 ret = i2c_smbus_read_byte_data(data->client, TCS3472_ATIME); 481 if (ret < 0) 482 return ret; 483 data->atime = ret; 484 485 ret = i2c_smbus_read_word_data(data->client, TCS3472_AILT); 486 if (ret < 0) 487 return ret; 488 data->low_thresh = ret; 489 490 ret = i2c_smbus_read_word_data(data->client, TCS3472_AIHT); 491 if (ret < 0) 492 return ret; 493 data->high_thresh = ret; 494 495 data->apers = 1; 496 ret = i2c_smbus_write_byte_data(data->client, TCS3472_PERS, 497 data->apers); 498 if (ret < 0) 499 return ret; 500 501 ret = i2c_smbus_read_byte_data(data->client, TCS3472_ENABLE); 502 if (ret < 0) 503 return ret; 504 505 /* enable device */ 506 data->enable = ret | TCS3472_ENABLE_PON | TCS3472_ENABLE_AEN; 507 data->enable &= ~TCS3472_ENABLE_AIEN; 508 ret = i2c_smbus_write_byte_data(data->client, TCS3472_ENABLE, 509 data->enable); 510 if (ret < 0) 511 return ret; 512 513 ret = iio_triggered_buffer_setup(indio_dev, NULL, 514 tcs3472_trigger_handler, NULL); 515 if (ret < 0) 516 return ret; 517 518 if (client->irq) { 519 ret = request_threaded_irq(client->irq, NULL, 520 tcs3472_event_handler, 521 IRQF_TRIGGER_FALLING | IRQF_SHARED | 522 IRQF_ONESHOT, 523 client->name, indio_dev); 524 if (ret) 525 goto buffer_cleanup; 526 } 527 528 ret = iio_device_register(indio_dev); 529 if (ret < 0) 530 goto free_irq; 531 532 return 0; 533 534 free_irq: 535 if (client->irq) 536 free_irq(client->irq, indio_dev); 537 buffer_cleanup: 538 iio_triggered_buffer_cleanup(indio_dev); 539 return ret; 540 } 541 542 static int tcs3472_powerdown(struct tcs3472_data *data) 543 { 544 int ret; 545 u8 enable_mask = TCS3472_ENABLE_AEN | TCS3472_ENABLE_PON; 546 547 mutex_lock(&data->lock); 548 549 ret = i2c_smbus_write_byte_data(data->client, TCS3472_ENABLE, 550 data->enable & ~enable_mask); 551 if (!ret) 552 data->enable &= ~enable_mask; 553 554 mutex_unlock(&data->lock); 555 556 return ret; 557 } 558 559 static void tcs3472_remove(struct i2c_client *client) 560 { 561 struct iio_dev *indio_dev = i2c_get_clientdata(client); 562 563 iio_device_unregister(indio_dev); 564 if (client->irq) 565 free_irq(client->irq, indio_dev); 566 iio_triggered_buffer_cleanup(indio_dev); 567 tcs3472_powerdown(iio_priv(indio_dev)); 568 } 569 570 static int tcs3472_suspend(struct device *dev) 571 { 572 struct tcs3472_data *data = iio_priv(i2c_get_clientdata( 573 to_i2c_client(dev))); 574 return tcs3472_powerdown(data); 575 } 576 577 static int tcs3472_resume(struct device *dev) 578 { 579 struct tcs3472_data *data = iio_priv(i2c_get_clientdata( 580 to_i2c_client(dev))); 581 int ret; 582 u8 enable_mask = TCS3472_ENABLE_AEN | TCS3472_ENABLE_PON; 583 584 mutex_lock(&data->lock); 585 586 ret = i2c_smbus_write_byte_data(data->client, TCS3472_ENABLE, 587 data->enable | enable_mask); 588 if (!ret) 589 data->enable |= enable_mask; 590 591 mutex_unlock(&data->lock); 592 593 return ret; 594 } 595 596 static DEFINE_SIMPLE_DEV_PM_OPS(tcs3472_pm_ops, tcs3472_suspend, 597 tcs3472_resume); 598 599 static const struct i2c_device_id tcs3472_id[] = { 600 { "tcs3472" }, 601 { } 602 }; 603 MODULE_DEVICE_TABLE(i2c, tcs3472_id); 604 605 static struct i2c_driver tcs3472_driver = { 606 .driver = { 607 .name = TCS3472_DRV_NAME, 608 .pm = pm_sleep_ptr(&tcs3472_pm_ops), 609 }, 610 .probe = tcs3472_probe, 611 .remove = tcs3472_remove, 612 .id_table = tcs3472_id, 613 }; 614 module_i2c_driver(tcs3472_driver); 615 616 MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>"); 617 MODULE_DESCRIPTION("TCS3472 color light sensors driver"); 618 MODULE_LICENSE("GPL"); 619