1 /* 2 * tcs3472.c - Support for TAOS TCS3472 color light-to-digital converter 3 * 4 * Copyright (c) 2013 Peter Meerwald <pmeerw@pmeerw.net> 5 * 6 * This file is subject to the terms and conditions of version 2 of 7 * the GNU General Public License. See the file COPYING in the main 8 * directory of this archive for more details. 9 * 10 * Color light sensor with 16-bit channels for red, green, blue, clear); 11 * 7-bit I2C slave address 0x39 (TCS34721, TCS34723) or 0x29 (TCS34725, 12 * TCS34727) 13 * 14 * Datasheet: http://ams.com/eng/content/download/319364/1117183/file/TCS3472_Datasheet_EN_v2.pdf 15 * 16 * TODO: wait time 17 */ 18 19 #include <linux/module.h> 20 #include <linux/i2c.h> 21 #include <linux/delay.h> 22 #include <linux/pm.h> 23 24 #include <linux/iio/iio.h> 25 #include <linux/iio/sysfs.h> 26 #include <linux/iio/events.h> 27 #include <linux/iio/trigger_consumer.h> 28 #include <linux/iio/buffer.h> 29 #include <linux/iio/triggered_buffer.h> 30 31 #define TCS3472_DRV_NAME "tcs3472" 32 33 #define TCS3472_COMMAND BIT(7) 34 #define TCS3472_AUTO_INCR BIT(5) 35 #define TCS3472_SPECIAL_FUNC (BIT(5) | BIT(6)) 36 37 #define TCS3472_INTR_CLEAR (TCS3472_COMMAND | TCS3472_SPECIAL_FUNC | 0x06) 38 39 #define TCS3472_ENABLE (TCS3472_COMMAND | 0x00) 40 #define TCS3472_ATIME (TCS3472_COMMAND | 0x01) 41 #define TCS3472_WTIME (TCS3472_COMMAND | 0x03) 42 #define TCS3472_AILT (TCS3472_COMMAND | TCS3472_AUTO_INCR | 0x04) 43 #define TCS3472_AIHT (TCS3472_COMMAND | TCS3472_AUTO_INCR | 0x06) 44 #define TCS3472_PERS (TCS3472_COMMAND | 0x0c) 45 #define TCS3472_CONFIG (TCS3472_COMMAND | 0x0d) 46 #define TCS3472_CONTROL (TCS3472_COMMAND | 0x0f) 47 #define TCS3472_ID (TCS3472_COMMAND | 0x12) 48 #define TCS3472_STATUS (TCS3472_COMMAND | 0x13) 49 #define TCS3472_CDATA (TCS3472_COMMAND | TCS3472_AUTO_INCR | 0x14) 50 #define TCS3472_RDATA (TCS3472_COMMAND | TCS3472_AUTO_INCR | 0x16) 51 #define TCS3472_GDATA (TCS3472_COMMAND | TCS3472_AUTO_INCR | 0x18) 52 #define TCS3472_BDATA (TCS3472_COMMAND | TCS3472_AUTO_INCR | 0x1a) 53 54 #define TCS3472_STATUS_AINT BIT(4) 55 #define TCS3472_STATUS_AVALID BIT(0) 56 #define TCS3472_ENABLE_AIEN BIT(4) 57 #define TCS3472_ENABLE_AEN BIT(1) 58 #define TCS3472_ENABLE_PON BIT(0) 59 #define TCS3472_CONTROL_AGAIN_MASK (BIT(0) | BIT(1)) 60 61 struct tcs3472_data { 62 struct i2c_client *client; 63 struct mutex lock; 64 u16 low_thresh; 65 u16 high_thresh; 66 u8 enable; 67 u8 control; 68 u8 atime; 69 u8 apers; 70 u16 buffer[8]; /* 4 16-bit channels + 64-bit timestamp */ 71 }; 72 73 static const struct iio_event_spec tcs3472_events[] = { 74 { 75 .type = IIO_EV_TYPE_THRESH, 76 .dir = IIO_EV_DIR_RISING, 77 .mask_separate = BIT(IIO_EV_INFO_VALUE), 78 }, { 79 .type = IIO_EV_TYPE_THRESH, 80 .dir = IIO_EV_DIR_FALLING, 81 .mask_separate = BIT(IIO_EV_INFO_VALUE), 82 }, { 83 .type = IIO_EV_TYPE_THRESH, 84 .dir = IIO_EV_DIR_EITHER, 85 .mask_separate = BIT(IIO_EV_INFO_ENABLE) | 86 BIT(IIO_EV_INFO_PERIOD), 87 }, 88 }; 89 90 #define TCS3472_CHANNEL(_color, _si, _addr) { \ 91 .type = IIO_INTENSITY, \ 92 .modified = 1, \ 93 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ 94 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_CALIBSCALE) | \ 95 BIT(IIO_CHAN_INFO_INT_TIME), \ 96 .channel2 = IIO_MOD_LIGHT_##_color, \ 97 .address = _addr, \ 98 .scan_index = _si, \ 99 .scan_type = { \ 100 .sign = 'u', \ 101 .realbits = 16, \ 102 .storagebits = 16, \ 103 .endianness = IIO_CPU, \ 104 }, \ 105 .event_spec = _si ? NULL : tcs3472_events, \ 106 .num_event_specs = _si ? 0 : ARRAY_SIZE(tcs3472_events), \ 107 } 108 109 static const int tcs3472_agains[] = { 1, 4, 16, 60 }; 110 111 static const struct iio_chan_spec tcs3472_channels[] = { 112 TCS3472_CHANNEL(CLEAR, 0, TCS3472_CDATA), 113 TCS3472_CHANNEL(RED, 1, TCS3472_RDATA), 114 TCS3472_CHANNEL(GREEN, 2, TCS3472_GDATA), 115 TCS3472_CHANNEL(BLUE, 3, TCS3472_BDATA), 116 IIO_CHAN_SOFT_TIMESTAMP(4), 117 }; 118 119 static int tcs3472_req_data(struct tcs3472_data *data) 120 { 121 int tries = 50; 122 int ret; 123 124 while (tries--) { 125 ret = i2c_smbus_read_byte_data(data->client, TCS3472_STATUS); 126 if (ret < 0) 127 return ret; 128 if (ret & TCS3472_STATUS_AVALID) 129 break; 130 msleep(20); 131 } 132 133 if (tries < 0) { 134 dev_err(&data->client->dev, "data not ready\n"); 135 return -EIO; 136 } 137 138 return 0; 139 } 140 141 static int tcs3472_read_raw(struct iio_dev *indio_dev, 142 struct iio_chan_spec const *chan, 143 int *val, int *val2, long mask) 144 { 145 struct tcs3472_data *data = iio_priv(indio_dev); 146 int ret; 147 148 switch (mask) { 149 case IIO_CHAN_INFO_RAW: 150 ret = iio_device_claim_direct_mode(indio_dev); 151 if (ret) 152 return ret; 153 ret = tcs3472_req_data(data); 154 if (ret < 0) { 155 iio_device_release_direct_mode(indio_dev); 156 return ret; 157 } 158 ret = i2c_smbus_read_word_data(data->client, chan->address); 159 iio_device_release_direct_mode(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, int 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 for_each_set_bit(i, indio_dev->active_scan_mask, 386 indio_dev->masklength) { 387 ret = i2c_smbus_read_word_data(data->client, 388 TCS3472_CDATA + 2*i); 389 if (ret < 0) 390 goto done; 391 392 data->buffer[j++] = ret; 393 } 394 395 iio_push_to_buffers_with_timestamp(indio_dev, data->buffer, 396 iio_get_time_ns(indio_dev)); 397 398 done: 399 iio_trigger_notify_done(indio_dev->trig); 400 401 return IRQ_HANDLED; 402 } 403 404 static ssize_t tcs3472_show_int_time_available(struct device *dev, 405 struct device_attribute *attr, 406 char *buf) 407 { 408 size_t len = 0; 409 int i; 410 411 for (i = 1; i <= 256; i++) 412 len += scnprintf(buf + len, PAGE_SIZE - len, "0.%06d ", 413 2400 * i); 414 415 /* replace trailing space by newline */ 416 buf[len - 1] = '\n'; 417 418 return len; 419 } 420 421 static IIO_CONST_ATTR(calibscale_available, "1 4 16 60"); 422 static IIO_DEV_ATTR_INT_TIME_AVAIL(tcs3472_show_int_time_available); 423 424 static struct attribute *tcs3472_attributes[] = { 425 &iio_const_attr_calibscale_available.dev_attr.attr, 426 &iio_dev_attr_integration_time_available.dev_attr.attr, 427 NULL 428 }; 429 430 static const struct attribute_group tcs3472_attribute_group = { 431 .attrs = tcs3472_attributes, 432 }; 433 434 static const struct iio_info tcs3472_info = { 435 .read_raw = tcs3472_read_raw, 436 .write_raw = tcs3472_write_raw, 437 .read_event_value = tcs3472_read_event, 438 .write_event_value = tcs3472_write_event, 439 .read_event_config = tcs3472_read_event_config, 440 .write_event_config = tcs3472_write_event_config, 441 .attrs = &tcs3472_attribute_group, 442 }; 443 444 static int tcs3472_probe(struct i2c_client *client, 445 const struct i2c_device_id *id) 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->dev.parent = &client->dev; 461 indio_dev->info = &tcs3472_info; 462 indio_dev->name = TCS3472_DRV_NAME; 463 indio_dev->channels = tcs3472_channels; 464 indio_dev->num_channels = ARRAY_SIZE(tcs3472_channels); 465 indio_dev->modes = INDIO_DIRECT_MODE; 466 467 ret = i2c_smbus_read_byte_data(data->client, TCS3472_ID); 468 if (ret < 0) 469 return ret; 470 471 if (ret == 0x44) 472 dev_info(&client->dev, "TCS34721/34725 found\n"); 473 else if (ret == 0x4d) 474 dev_info(&client->dev, "TCS34723/34727 found\n"); 475 else 476 return -ENODEV; 477 478 ret = i2c_smbus_read_byte_data(data->client, TCS3472_CONTROL); 479 if (ret < 0) 480 return ret; 481 data->control = ret; 482 483 ret = i2c_smbus_read_byte_data(data->client, TCS3472_ATIME); 484 if (ret < 0) 485 return ret; 486 data->atime = ret; 487 488 ret = i2c_smbus_read_word_data(data->client, TCS3472_AILT); 489 if (ret < 0) 490 return ret; 491 data->low_thresh = ret; 492 493 ret = i2c_smbus_read_word_data(data->client, TCS3472_AIHT); 494 if (ret < 0) 495 return ret; 496 data->high_thresh = ret; 497 498 data->apers = 1; 499 ret = i2c_smbus_write_byte_data(data->client, TCS3472_PERS, 500 data->apers); 501 if (ret < 0) 502 return ret; 503 504 ret = i2c_smbus_read_byte_data(data->client, TCS3472_ENABLE); 505 if (ret < 0) 506 return ret; 507 508 /* enable device */ 509 data->enable = ret | TCS3472_ENABLE_PON | TCS3472_ENABLE_AEN; 510 data->enable &= ~TCS3472_ENABLE_AIEN; 511 ret = i2c_smbus_write_byte_data(data->client, TCS3472_ENABLE, 512 data->enable); 513 if (ret < 0) 514 return ret; 515 516 ret = iio_triggered_buffer_setup(indio_dev, NULL, 517 tcs3472_trigger_handler, NULL); 518 if (ret < 0) 519 return ret; 520 521 if (client->irq) { 522 ret = request_threaded_irq(client->irq, NULL, 523 tcs3472_event_handler, 524 IRQF_TRIGGER_FALLING | IRQF_SHARED | 525 IRQF_ONESHOT, 526 client->name, indio_dev); 527 if (ret) 528 goto buffer_cleanup; 529 } 530 531 ret = iio_device_register(indio_dev); 532 if (ret < 0) 533 goto free_irq; 534 535 return 0; 536 537 free_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 int 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 free_irq(client->irq, indio_dev); 567 iio_triggered_buffer_cleanup(indio_dev); 568 tcs3472_powerdown(iio_priv(indio_dev)); 569 570 return 0; 571 } 572 573 #ifdef CONFIG_PM_SLEEP 574 static int tcs3472_suspend(struct device *dev) 575 { 576 struct tcs3472_data *data = iio_priv(i2c_get_clientdata( 577 to_i2c_client(dev))); 578 return tcs3472_powerdown(data); 579 } 580 581 static int tcs3472_resume(struct device *dev) 582 { 583 struct tcs3472_data *data = iio_priv(i2c_get_clientdata( 584 to_i2c_client(dev))); 585 int ret; 586 u8 enable_mask = TCS3472_ENABLE_AEN | TCS3472_ENABLE_PON; 587 588 mutex_lock(&data->lock); 589 590 ret = i2c_smbus_write_byte_data(data->client, TCS3472_ENABLE, 591 data->enable | enable_mask); 592 if (!ret) 593 data->enable |= enable_mask; 594 595 mutex_unlock(&data->lock); 596 597 return ret; 598 } 599 #endif 600 601 static SIMPLE_DEV_PM_OPS(tcs3472_pm_ops, tcs3472_suspend, tcs3472_resume); 602 603 static const struct i2c_device_id tcs3472_id[] = { 604 { "tcs3472", 0 }, 605 { } 606 }; 607 MODULE_DEVICE_TABLE(i2c, tcs3472_id); 608 609 static struct i2c_driver tcs3472_driver = { 610 .driver = { 611 .name = TCS3472_DRV_NAME, 612 .pm = &tcs3472_pm_ops, 613 }, 614 .probe = tcs3472_probe, 615 .remove = tcs3472_remove, 616 .id_table = tcs3472_id, 617 }; 618 module_i2c_driver(tcs3472_driver); 619 620 MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>"); 621 MODULE_DESCRIPTION("TCS3472 color light sensors driver"); 622 MODULE_LICENSE("GPL"); 623