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 s64 timestamp __aligned(8); 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 ret = iio_device_claim_direct_mode(indio_dev); 152 if (ret) 153 return ret; 154 ret = tcs3472_req_data(data); 155 if (ret < 0) { 156 iio_device_release_direct_mode(indio_dev); 157 return ret; 158 } 159 ret = i2c_smbus_read_word_data(data->client, chan->address); 160 iio_device_release_direct_mode(indio_dev); 161 if (ret < 0) 162 return ret; 163 *val = ret; 164 return IIO_VAL_INT; 165 case IIO_CHAN_INFO_CALIBSCALE: 166 *val = tcs3472_agains[data->control & 167 TCS3472_CONTROL_AGAIN_MASK]; 168 return IIO_VAL_INT; 169 case IIO_CHAN_INFO_INT_TIME: 170 *val = 0; 171 *val2 = (256 - data->atime) * 2400; 172 return IIO_VAL_INT_PLUS_MICRO; 173 } 174 return -EINVAL; 175 } 176 177 static int tcs3472_write_raw(struct iio_dev *indio_dev, 178 struct iio_chan_spec const *chan, 179 int val, int val2, long mask) 180 { 181 struct tcs3472_data *data = iio_priv(indio_dev); 182 int i; 183 184 switch (mask) { 185 case IIO_CHAN_INFO_CALIBSCALE: 186 if (val2 != 0) 187 return -EINVAL; 188 for (i = 0; i < ARRAY_SIZE(tcs3472_agains); i++) { 189 if (val == tcs3472_agains[i]) { 190 data->control &= ~TCS3472_CONTROL_AGAIN_MASK; 191 data->control |= i; 192 return i2c_smbus_write_byte_data( 193 data->client, TCS3472_CONTROL, 194 data->control); 195 } 196 } 197 return -EINVAL; 198 case IIO_CHAN_INFO_INT_TIME: 199 if (val != 0) 200 return -EINVAL; 201 for (i = 0; i < 256; i++) { 202 if (val2 == (256 - i) * 2400) { 203 data->atime = i; 204 return i2c_smbus_write_byte_data( 205 data->client, TCS3472_ATIME, 206 data->atime); 207 } 208 209 } 210 return -EINVAL; 211 } 212 return -EINVAL; 213 } 214 215 /* 216 * Translation from APERS field value to the number of consecutive out-of-range 217 * clear channel values before an interrupt is generated 218 */ 219 static const int tcs3472_intr_pers[] = { 220 0, 1, 2, 3, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60 221 }; 222 223 static int tcs3472_read_event(struct iio_dev *indio_dev, 224 const struct iio_chan_spec *chan, enum iio_event_type type, 225 enum iio_event_direction dir, enum iio_event_info info, int *val, 226 int *val2) 227 { 228 struct tcs3472_data *data = iio_priv(indio_dev); 229 int ret; 230 unsigned int period; 231 232 mutex_lock(&data->lock); 233 234 switch (info) { 235 case IIO_EV_INFO_VALUE: 236 *val = (dir == IIO_EV_DIR_RISING) ? 237 data->high_thresh : data->low_thresh; 238 ret = IIO_VAL_INT; 239 break; 240 case IIO_EV_INFO_PERIOD: 241 period = (256 - data->atime) * 2400 * 242 tcs3472_intr_pers[data->apers]; 243 *val = period / USEC_PER_SEC; 244 *val2 = period % USEC_PER_SEC; 245 ret = IIO_VAL_INT_PLUS_MICRO; 246 break; 247 default: 248 ret = -EINVAL; 249 break; 250 } 251 252 mutex_unlock(&data->lock); 253 254 return ret; 255 } 256 257 static int tcs3472_write_event(struct iio_dev *indio_dev, 258 const struct iio_chan_spec *chan, enum iio_event_type type, 259 enum iio_event_direction dir, enum iio_event_info info, int val, 260 int val2) 261 { 262 struct tcs3472_data *data = iio_priv(indio_dev); 263 int ret; 264 u8 command; 265 int period; 266 int i; 267 268 mutex_lock(&data->lock); 269 switch (info) { 270 case IIO_EV_INFO_VALUE: 271 switch (dir) { 272 case IIO_EV_DIR_RISING: 273 command = TCS3472_AIHT; 274 break; 275 case IIO_EV_DIR_FALLING: 276 command = TCS3472_AILT; 277 break; 278 default: 279 ret = -EINVAL; 280 goto error; 281 } 282 ret = i2c_smbus_write_word_data(data->client, command, val); 283 if (ret) 284 goto error; 285 286 if (dir == IIO_EV_DIR_RISING) 287 data->high_thresh = val; 288 else 289 data->low_thresh = val; 290 break; 291 case IIO_EV_INFO_PERIOD: 292 period = val * USEC_PER_SEC + val2; 293 for (i = 1; i < ARRAY_SIZE(tcs3472_intr_pers) - 1; i++) { 294 if (period <= (256 - data->atime) * 2400 * 295 tcs3472_intr_pers[i]) 296 break; 297 } 298 ret = i2c_smbus_write_byte_data(data->client, TCS3472_PERS, i); 299 if (ret) 300 goto error; 301 302 data->apers = i; 303 break; 304 default: 305 ret = -EINVAL; 306 break; 307 } 308 error: 309 mutex_unlock(&data->lock); 310 311 return ret; 312 } 313 314 static int tcs3472_read_event_config(struct iio_dev *indio_dev, 315 const struct iio_chan_spec *chan, enum iio_event_type type, 316 enum iio_event_direction dir) 317 { 318 struct tcs3472_data *data = iio_priv(indio_dev); 319 int ret; 320 321 mutex_lock(&data->lock); 322 ret = !!(data->enable & TCS3472_ENABLE_AIEN); 323 mutex_unlock(&data->lock); 324 325 return ret; 326 } 327 328 static int tcs3472_write_event_config(struct iio_dev *indio_dev, 329 const struct iio_chan_spec *chan, enum iio_event_type type, 330 enum iio_event_direction dir, int state) 331 { 332 struct tcs3472_data *data = iio_priv(indio_dev); 333 int ret = 0; 334 u8 enable_old; 335 336 mutex_lock(&data->lock); 337 338 enable_old = data->enable; 339 340 if (state) 341 data->enable |= TCS3472_ENABLE_AIEN; 342 else 343 data->enable &= ~TCS3472_ENABLE_AIEN; 344 345 if (enable_old != data->enable) { 346 ret = i2c_smbus_write_byte_data(data->client, TCS3472_ENABLE, 347 data->enable); 348 if (ret) 349 data->enable = enable_old; 350 } 351 mutex_unlock(&data->lock); 352 353 return ret; 354 } 355 356 static irqreturn_t tcs3472_event_handler(int irq, void *priv) 357 { 358 struct iio_dev *indio_dev = priv; 359 struct tcs3472_data *data = iio_priv(indio_dev); 360 int ret; 361 362 ret = i2c_smbus_read_byte_data(data->client, TCS3472_STATUS); 363 if (ret >= 0 && (ret & TCS3472_STATUS_AINT)) { 364 iio_push_event(indio_dev, IIO_UNMOD_EVENT_CODE(IIO_INTENSITY, 0, 365 IIO_EV_TYPE_THRESH, 366 IIO_EV_DIR_EITHER), 367 iio_get_time_ns(indio_dev)); 368 369 i2c_smbus_read_byte_data(data->client, TCS3472_INTR_CLEAR); 370 } 371 372 return IRQ_HANDLED; 373 } 374 375 static irqreturn_t tcs3472_trigger_handler(int irq, void *p) 376 { 377 struct iio_poll_func *pf = p; 378 struct iio_dev *indio_dev = pf->indio_dev; 379 struct tcs3472_data *data = iio_priv(indio_dev); 380 int i, j = 0; 381 382 int ret = tcs3472_req_data(data); 383 if (ret < 0) 384 goto done; 385 386 for_each_set_bit(i, indio_dev->active_scan_mask, 387 indio_dev->masklength) { 388 ret = i2c_smbus_read_word_data(data->client, 389 TCS3472_CDATA + 2*i); 390 if (ret < 0) 391 goto done; 392 393 data->scan.chans[j++] = ret; 394 } 395 396 iio_push_to_buffers_with_timestamp(indio_dev, &data->scan, 397 iio_get_time_ns(indio_dev)); 398 399 done: 400 iio_trigger_notify_done(indio_dev->trig); 401 402 return IRQ_HANDLED; 403 } 404 405 static ssize_t tcs3472_show_int_time_available(struct device *dev, 406 struct device_attribute *attr, 407 char *buf) 408 { 409 size_t len = 0; 410 int i; 411 412 for (i = 1; i <= 256; i++) 413 len += scnprintf(buf + len, PAGE_SIZE - len, "0.%06d ", 414 2400 * i); 415 416 /* replace trailing space by newline */ 417 buf[len - 1] = '\n'; 418 419 return len; 420 } 421 422 static IIO_CONST_ATTR(calibscale_available, "1 4 16 60"); 423 static IIO_DEV_ATTR_INT_TIME_AVAIL(tcs3472_show_int_time_available); 424 425 static struct attribute *tcs3472_attributes[] = { 426 &iio_const_attr_calibscale_available.dev_attr.attr, 427 &iio_dev_attr_integration_time_available.dev_attr.attr, 428 NULL 429 }; 430 431 static const struct attribute_group tcs3472_attribute_group = { 432 .attrs = tcs3472_attributes, 433 }; 434 435 static const struct iio_info tcs3472_info = { 436 .read_raw = tcs3472_read_raw, 437 .write_raw = tcs3472_write_raw, 438 .read_event_value = tcs3472_read_event, 439 .write_event_value = tcs3472_write_event, 440 .read_event_config = tcs3472_read_event_config, 441 .write_event_config = tcs3472_write_event_config, 442 .attrs = &tcs3472_attribute_group, 443 }; 444 445 static int tcs3472_probe(struct i2c_client *client) 446 { 447 struct tcs3472_data *data; 448 struct iio_dev *indio_dev; 449 int ret; 450 451 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data)); 452 if (indio_dev == NULL) 453 return -ENOMEM; 454 455 data = iio_priv(indio_dev); 456 i2c_set_clientdata(client, indio_dev); 457 data->client = client; 458 mutex_init(&data->lock); 459 460 indio_dev->info = &tcs3472_info; 461 indio_dev->name = TCS3472_DRV_NAME; 462 indio_dev->channels = tcs3472_channels; 463 indio_dev->num_channels = ARRAY_SIZE(tcs3472_channels); 464 indio_dev->modes = INDIO_DIRECT_MODE; 465 466 ret = i2c_smbus_read_byte_data(data->client, TCS3472_ID); 467 if (ret < 0) 468 return ret; 469 470 if (ret == 0x44) 471 dev_info(&client->dev, "TCS34721/34725 found\n"); 472 else if (ret == 0x4d) 473 dev_info(&client->dev, "TCS34723/34727 found\n"); 474 else 475 return -ENODEV; 476 477 ret = i2c_smbus_read_byte_data(data->client, TCS3472_CONTROL); 478 if (ret < 0) 479 return ret; 480 data->control = ret; 481 482 ret = i2c_smbus_read_byte_data(data->client, TCS3472_ATIME); 483 if (ret < 0) 484 return ret; 485 data->atime = ret; 486 487 ret = i2c_smbus_read_word_data(data->client, TCS3472_AILT); 488 if (ret < 0) 489 return ret; 490 data->low_thresh = ret; 491 492 ret = i2c_smbus_read_word_data(data->client, TCS3472_AIHT); 493 if (ret < 0) 494 return ret; 495 data->high_thresh = ret; 496 497 data->apers = 1; 498 ret = i2c_smbus_write_byte_data(data->client, TCS3472_PERS, 499 data->apers); 500 if (ret < 0) 501 return ret; 502 503 ret = i2c_smbus_read_byte_data(data->client, TCS3472_ENABLE); 504 if (ret < 0) 505 return ret; 506 507 /* enable device */ 508 data->enable = ret | TCS3472_ENABLE_PON | TCS3472_ENABLE_AEN; 509 data->enable &= ~TCS3472_ENABLE_AIEN; 510 ret = i2c_smbus_write_byte_data(data->client, TCS3472_ENABLE, 511 data->enable); 512 if (ret < 0) 513 return ret; 514 515 ret = iio_triggered_buffer_setup(indio_dev, NULL, 516 tcs3472_trigger_handler, NULL); 517 if (ret < 0) 518 return ret; 519 520 if (client->irq) { 521 ret = request_threaded_irq(client->irq, NULL, 522 tcs3472_event_handler, 523 IRQF_TRIGGER_FALLING | IRQF_SHARED | 524 IRQF_ONESHOT, 525 client->name, indio_dev); 526 if (ret) 527 goto buffer_cleanup; 528 } 529 530 ret = iio_device_register(indio_dev); 531 if (ret < 0) 532 goto free_irq; 533 534 return 0; 535 536 free_irq: 537 if (client->irq) 538 free_irq(client->irq, indio_dev); 539 buffer_cleanup: 540 iio_triggered_buffer_cleanup(indio_dev); 541 return ret; 542 } 543 544 static int tcs3472_powerdown(struct tcs3472_data *data) 545 { 546 int ret; 547 u8 enable_mask = TCS3472_ENABLE_AEN | TCS3472_ENABLE_PON; 548 549 mutex_lock(&data->lock); 550 551 ret = i2c_smbus_write_byte_data(data->client, TCS3472_ENABLE, 552 data->enable & ~enable_mask); 553 if (!ret) 554 data->enable &= ~enable_mask; 555 556 mutex_unlock(&data->lock); 557 558 return ret; 559 } 560 561 static void tcs3472_remove(struct i2c_client *client) 562 { 563 struct iio_dev *indio_dev = i2c_get_clientdata(client); 564 565 iio_device_unregister(indio_dev); 566 if (client->irq) 567 free_irq(client->irq, indio_dev); 568 iio_triggered_buffer_cleanup(indio_dev); 569 tcs3472_powerdown(iio_priv(indio_dev)); 570 } 571 572 static int tcs3472_suspend(struct device *dev) 573 { 574 struct tcs3472_data *data = iio_priv(i2c_get_clientdata( 575 to_i2c_client(dev))); 576 return tcs3472_powerdown(data); 577 } 578 579 static int tcs3472_resume(struct device *dev) 580 { 581 struct tcs3472_data *data = iio_priv(i2c_get_clientdata( 582 to_i2c_client(dev))); 583 int ret; 584 u8 enable_mask = TCS3472_ENABLE_AEN | TCS3472_ENABLE_PON; 585 586 mutex_lock(&data->lock); 587 588 ret = i2c_smbus_write_byte_data(data->client, TCS3472_ENABLE, 589 data->enable | enable_mask); 590 if (!ret) 591 data->enable |= enable_mask; 592 593 mutex_unlock(&data->lock); 594 595 return ret; 596 } 597 598 static DEFINE_SIMPLE_DEV_PM_OPS(tcs3472_pm_ops, tcs3472_suspend, 599 tcs3472_resume); 600 601 static const struct i2c_device_id tcs3472_id[] = { 602 { "tcs3472", 0 }, 603 { } 604 }; 605 MODULE_DEVICE_TABLE(i2c, tcs3472_id); 606 607 static struct i2c_driver tcs3472_driver = { 608 .driver = { 609 .name = TCS3472_DRV_NAME, 610 .pm = pm_sleep_ptr(&tcs3472_pm_ops), 611 }, 612 .probe = tcs3472_probe, 613 .remove = tcs3472_remove, 614 .id_table = tcs3472_id, 615 }; 616 module_i2c_driver(tcs3472_driver); 617 618 MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>"); 619 MODULE_DESCRIPTION("TCS3472 color light sensors driver"); 620 MODULE_LICENSE("GPL"); 621