1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * zopt2201.c - Support for IDT ZOPT2201 ambient light and UV B sensor 4 * 5 * Copyright 2017 Peter Meerwald-Stadler <pmeerw@pmeerw.net> 6 * 7 * Datasheet: https://www.idt.com/document/dst/zopt2201-datasheet 8 * 7-bit I2C slave addresses 0x53 (default) or 0x52 (programmed) 9 * 10 * TODO: interrupt support, ALS/UVB raw mode 11 */ 12 13 #include <linux/module.h> 14 #include <linux/i2c.h> 15 #include <linux/mutex.h> 16 #include <linux/err.h> 17 #include <linux/delay.h> 18 19 #include <linux/iio/iio.h> 20 #include <linux/iio/sysfs.h> 21 22 #include <linux/unaligned.h> 23 24 #define ZOPT2201_DRV_NAME "zopt2201" 25 26 /* Registers */ 27 #define ZOPT2201_MAIN_CTRL 0x00 28 #define ZOPT2201_LS_MEAS_RATE 0x04 29 #define ZOPT2201_LS_GAIN 0x05 30 #define ZOPT2201_PART_ID 0x06 31 #define ZOPT2201_MAIN_STATUS 0x07 32 #define ZOPT2201_ALS_DATA 0x0d /* LSB first, 13 to 20 bits */ 33 #define ZOPT2201_UVB_DATA 0x10 /* LSB first, 13 to 20 bits */ 34 #define ZOPT2201_UV_COMP_DATA 0x13 /* LSB first, 13 to 20 bits */ 35 #define ZOPT2201_COMP_DATA 0x16 /* LSB first, 13 to 20 bits */ 36 #define ZOPT2201_INT_CFG 0x19 37 #define ZOPT2201_INT_PST 0x1a 38 39 #define ZOPT2201_MAIN_CTRL_LS_MODE BIT(3) /* 0 .. ALS, 1 .. UV B */ 40 #define ZOPT2201_MAIN_CTRL_LS_EN BIT(1) 41 42 /* Values for ZOPT2201_LS_MEAS_RATE resolution / bit width */ 43 #define ZOPT2201_MEAS_RES_20BIT 0 /* takes 400 ms */ 44 #define ZOPT2201_MEAS_RES_19BIT 1 /* takes 200 ms */ 45 #define ZOPT2201_MEAS_RES_18BIT 2 /* takes 100 ms, default */ 46 #define ZOPT2201_MEAS_RES_17BIT 3 /* takes 50 ms */ 47 #define ZOPT2201_MEAS_RES_16BIT 4 /* takes 25 ms */ 48 #define ZOPT2201_MEAS_RES_13BIT 5 /* takes 3.125 ms */ 49 #define ZOPT2201_MEAS_RES_SHIFT 4 50 51 /* Values for ZOPT2201_LS_MEAS_RATE measurement rate */ 52 #define ZOPT2201_MEAS_FREQ_25MS 0 53 #define ZOPT2201_MEAS_FREQ_50MS 1 54 #define ZOPT2201_MEAS_FREQ_100MS 2 /* default */ 55 #define ZOPT2201_MEAS_FREQ_200MS 3 56 #define ZOPT2201_MEAS_FREQ_500MS 4 57 #define ZOPT2201_MEAS_FREQ_1000MS 5 58 #define ZOPT2201_MEAS_FREQ_2000MS 6 59 60 /* Values for ZOPT2201_LS_GAIN */ 61 #define ZOPT2201_LS_GAIN_1 0 62 #define ZOPT2201_LS_GAIN_3 1 63 #define ZOPT2201_LS_GAIN_6 2 64 #define ZOPT2201_LS_GAIN_9 3 65 #define ZOPT2201_LS_GAIN_18 4 66 67 /* Values for ZOPT2201_MAIN_STATUS */ 68 #define ZOPT2201_MAIN_STATUS_POWERON BIT(5) 69 #define ZOPT2201_MAIN_STATUS_INT BIT(4) 70 #define ZOPT2201_MAIN_STATUS_DRDY BIT(3) 71 72 #define ZOPT2201_PART_NUMBER 0xb2 73 74 struct zopt2201_data { 75 struct i2c_client *client; 76 struct mutex lock; 77 u8 gain; 78 u8 res; 79 u8 rate; 80 }; 81 82 static const struct { 83 unsigned int gain; /* gain factor */ 84 unsigned int scale; /* micro lux per count */ 85 } zopt2201_gain_als[] = { 86 { 1, 19200000 }, 87 { 3, 6400000 }, 88 { 6, 3200000 }, 89 { 9, 2133333 }, 90 { 18, 1066666 }, 91 }; 92 93 static const struct { 94 unsigned int gain; /* gain factor */ 95 unsigned int scale; /* micro W/m2 per count */ 96 } zopt2201_gain_uvb[] = { 97 { 1, 460800 }, 98 { 3, 153600 }, 99 { 6, 76800 }, 100 { 9, 51200 }, 101 { 18, 25600 }, 102 }; 103 104 static const struct { 105 unsigned int bits; /* sensor resolution in bits */ 106 unsigned long us; /* measurement time in micro seconds */ 107 } zopt2201_resolution[] = { 108 { 20, 400000 }, 109 { 19, 200000 }, 110 { 18, 100000 }, 111 { 17, 50000 }, 112 { 16, 25000 }, 113 { 13, 3125 }, 114 }; 115 116 static const struct { 117 unsigned int scale, uscale; /* scale factor as integer + micro */ 118 u8 gain; /* gain register value */ 119 u8 res; /* resolution register value */ 120 } zopt2201_scale_als[] = { 121 { 19, 200000, 0, 5 }, 122 { 6, 400000, 1, 5 }, 123 { 3, 200000, 2, 5 }, 124 { 2, 400000, 0, 4 }, 125 { 2, 133333, 3, 5 }, 126 { 1, 200000, 0, 3 }, 127 { 1, 66666, 4, 5 }, 128 { 0, 800000, 1, 4 }, 129 { 0, 600000, 0, 2 }, 130 { 0, 400000, 2, 4 }, 131 { 0, 300000, 0, 1 }, 132 { 0, 266666, 3, 4 }, 133 { 0, 200000, 2, 3 }, 134 { 0, 150000, 0, 0 }, 135 { 0, 133333, 4, 4 }, 136 { 0, 100000, 2, 2 }, 137 { 0, 66666, 4, 3 }, 138 { 0, 50000, 2, 1 }, 139 { 0, 33333, 4, 2 }, 140 { 0, 25000, 2, 0 }, 141 { 0, 16666, 4, 1 }, 142 { 0, 8333, 4, 0 }, 143 }; 144 145 static const struct { 146 unsigned int scale, uscale; /* scale factor as integer + micro */ 147 u8 gain; /* gain register value */ 148 u8 res; /* resolution register value */ 149 } zopt2201_scale_uvb[] = { 150 { 0, 460800, 0, 5 }, 151 { 0, 153600, 1, 5 }, 152 { 0, 76800, 2, 5 }, 153 { 0, 57600, 0, 4 }, 154 { 0, 51200, 3, 5 }, 155 { 0, 28800, 0, 3 }, 156 { 0, 25600, 4, 5 }, 157 { 0, 19200, 1, 4 }, 158 { 0, 14400, 0, 2 }, 159 { 0, 9600, 2, 4 }, 160 { 0, 7200, 0, 1 }, 161 { 0, 6400, 3, 4 }, 162 { 0, 4800, 2, 3 }, 163 { 0, 3600, 0, 0 }, 164 { 0, 3200, 4, 4 }, 165 { 0, 2400, 2, 2 }, 166 { 0, 1600, 4, 3 }, 167 { 0, 1200, 2, 1 }, 168 { 0, 800, 4, 2 }, 169 { 0, 600, 2, 0 }, 170 { 0, 400, 4, 1 }, 171 { 0, 200, 4, 0 }, 172 }; 173 174 static int zopt2201_enable_mode(struct zopt2201_data *data, bool uvb_mode) 175 { 176 u8 out = ZOPT2201_MAIN_CTRL_LS_EN; 177 178 if (uvb_mode) 179 out |= ZOPT2201_MAIN_CTRL_LS_MODE; 180 181 return i2c_smbus_write_byte_data(data->client, ZOPT2201_MAIN_CTRL, out); 182 } 183 184 static int zopt2201_read(struct zopt2201_data *data, u8 reg) 185 { 186 struct i2c_client *client = data->client; 187 int tries = 10; 188 u8 buf[3]; 189 int ret; 190 191 mutex_lock(&data->lock); 192 ret = zopt2201_enable_mode(data, reg == ZOPT2201_UVB_DATA); 193 if (ret < 0) 194 goto fail; 195 196 while (tries--) { 197 unsigned long t = zopt2201_resolution[data->res].us; 198 199 if (t <= 20000) 200 usleep_range(t, t + 1000); 201 else 202 msleep(t / 1000); 203 ret = i2c_smbus_read_byte_data(client, ZOPT2201_MAIN_STATUS); 204 if (ret < 0) 205 goto fail; 206 if (ret & ZOPT2201_MAIN_STATUS_DRDY) 207 break; 208 } 209 210 if (tries < 0) { 211 ret = -ETIMEDOUT; 212 goto fail; 213 } 214 215 ret = i2c_smbus_read_i2c_block_data(client, reg, sizeof(buf), buf); 216 if (ret < 0) 217 goto fail; 218 219 ret = i2c_smbus_write_byte_data(client, ZOPT2201_MAIN_CTRL, 0x00); 220 if (ret < 0) 221 goto fail; 222 mutex_unlock(&data->lock); 223 224 return get_unaligned_le24(&buf[0]); 225 226 fail: 227 mutex_unlock(&data->lock); 228 return ret; 229 } 230 231 static const struct iio_chan_spec zopt2201_channels[] = { 232 { 233 .type = IIO_LIGHT, 234 .address = ZOPT2201_ALS_DATA, 235 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | 236 BIT(IIO_CHAN_INFO_SCALE), 237 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_INT_TIME), 238 }, 239 { 240 .type = IIO_INTENSITY, 241 .modified = 1, 242 .channel2 = IIO_MOD_LIGHT_UV, 243 .address = ZOPT2201_UVB_DATA, 244 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | 245 BIT(IIO_CHAN_INFO_SCALE), 246 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_INT_TIME), 247 }, 248 { 249 .type = IIO_UVINDEX, 250 .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED), 251 }, 252 }; 253 254 static int zopt2201_read_raw(struct iio_dev *indio_dev, 255 struct iio_chan_spec const *chan, 256 int *val, int *val2, long mask) 257 { 258 struct zopt2201_data *data = iio_priv(indio_dev); 259 u64 tmp; 260 int ret; 261 262 switch (mask) { 263 case IIO_CHAN_INFO_RAW: 264 ret = zopt2201_read(data, chan->address); 265 if (ret < 0) 266 return ret; 267 *val = ret; 268 return IIO_VAL_INT; 269 case IIO_CHAN_INFO_PROCESSED: 270 ret = zopt2201_read(data, ZOPT2201_UVB_DATA); 271 if (ret < 0) 272 return ret; 273 *val = ret * 18 * 274 (1 << (20 - zopt2201_resolution[data->res].bits)) / 275 zopt2201_gain_uvb[data->gain].gain; 276 return IIO_VAL_INT; 277 case IIO_CHAN_INFO_SCALE: 278 switch (chan->address) { 279 case ZOPT2201_ALS_DATA: 280 *val = zopt2201_gain_als[data->gain].scale; 281 break; 282 case ZOPT2201_UVB_DATA: 283 *val = zopt2201_gain_uvb[data->gain].scale; 284 break; 285 default: 286 return -EINVAL; 287 } 288 289 *val2 = 1000000; 290 *val2 *= (1 << (zopt2201_resolution[data->res].bits - 13)); 291 tmp = div_s64(*val * 1000000ULL, *val2); 292 *val = div_s64_rem(tmp, 1000000, val2); 293 294 return IIO_VAL_INT_PLUS_MICRO; 295 case IIO_CHAN_INFO_INT_TIME: 296 *val = 0; 297 *val2 = zopt2201_resolution[data->res].us; 298 return IIO_VAL_INT_PLUS_MICRO; 299 default: 300 return -EINVAL; 301 } 302 } 303 304 static int zopt2201_set_resolution(struct zopt2201_data *data, u8 res) 305 { 306 int ret; 307 308 ret = i2c_smbus_write_byte_data(data->client, ZOPT2201_LS_MEAS_RATE, 309 (res << ZOPT2201_MEAS_RES_SHIFT) | 310 data->rate); 311 if (ret < 0) 312 return ret; 313 314 data->res = res; 315 316 return 0; 317 } 318 319 static int zopt2201_write_resolution(struct zopt2201_data *data, 320 int val, int val2) 321 { 322 int i, ret; 323 324 if (val != 0) 325 return -EINVAL; 326 327 for (i = 0; i < ARRAY_SIZE(zopt2201_resolution); i++) 328 if (val2 == zopt2201_resolution[i].us) { 329 mutex_lock(&data->lock); 330 ret = zopt2201_set_resolution(data, i); 331 mutex_unlock(&data->lock); 332 return ret; 333 } 334 335 return -EINVAL; 336 } 337 338 static int zopt2201_set_gain(struct zopt2201_data *data, u8 gain) 339 { 340 int ret; 341 342 ret = i2c_smbus_write_byte_data(data->client, ZOPT2201_LS_GAIN, gain); 343 if (ret < 0) 344 return ret; 345 346 data->gain = gain; 347 348 return 0; 349 } 350 351 static int zopt2201_write_scale_als_by_idx(struct zopt2201_data *data, int idx) 352 { 353 int ret; 354 355 mutex_lock(&data->lock); 356 ret = zopt2201_set_resolution(data, zopt2201_scale_als[idx].res); 357 if (ret < 0) 358 goto unlock; 359 360 ret = zopt2201_set_gain(data, zopt2201_scale_als[idx].gain); 361 362 unlock: 363 mutex_unlock(&data->lock); 364 return ret; 365 } 366 367 static int zopt2201_write_scale_als(struct zopt2201_data *data, 368 int val, int val2) 369 { 370 int i; 371 372 for (i = 0; i < ARRAY_SIZE(zopt2201_scale_als); i++) 373 if (val == zopt2201_scale_als[i].scale && 374 val2 == zopt2201_scale_als[i].uscale) { 375 return zopt2201_write_scale_als_by_idx(data, i); 376 } 377 378 return -EINVAL; 379 } 380 381 static int zopt2201_write_scale_uvb_by_idx(struct zopt2201_data *data, int idx) 382 { 383 int ret; 384 385 mutex_lock(&data->lock); 386 ret = zopt2201_set_resolution(data, zopt2201_scale_als[idx].res); 387 if (ret < 0) 388 goto unlock; 389 390 ret = zopt2201_set_gain(data, zopt2201_scale_als[idx].gain); 391 392 unlock: 393 mutex_unlock(&data->lock); 394 return ret; 395 } 396 397 static int zopt2201_write_scale_uvb(struct zopt2201_data *data, 398 int val, int val2) 399 { 400 int i; 401 402 for (i = 0; i < ARRAY_SIZE(zopt2201_scale_uvb); i++) 403 if (val == zopt2201_scale_uvb[i].scale && 404 val2 == zopt2201_scale_uvb[i].uscale) 405 return zopt2201_write_scale_uvb_by_idx(data, i); 406 407 return -EINVAL; 408 } 409 410 static int zopt2201_write_raw(struct iio_dev *indio_dev, 411 struct iio_chan_spec const *chan, 412 int val, int val2, long mask) 413 { 414 struct zopt2201_data *data = iio_priv(indio_dev); 415 416 switch (mask) { 417 case IIO_CHAN_INFO_INT_TIME: 418 return zopt2201_write_resolution(data, val, val2); 419 case IIO_CHAN_INFO_SCALE: 420 switch (chan->address) { 421 case ZOPT2201_ALS_DATA: 422 return zopt2201_write_scale_als(data, val, val2); 423 case ZOPT2201_UVB_DATA: 424 return zopt2201_write_scale_uvb(data, val, val2); 425 default: 426 return -EINVAL; 427 } 428 } 429 430 return -EINVAL; 431 } 432 433 static ssize_t zopt2201_show_int_time_available(struct device *dev, 434 struct device_attribute *attr, 435 char *buf) 436 { 437 size_t len = 0; 438 int i; 439 440 for (i = 0; i < ARRAY_SIZE(zopt2201_resolution); i++) 441 len += scnprintf(buf + len, PAGE_SIZE - len, "0.%06lu ", 442 zopt2201_resolution[i].us); 443 buf[len - 1] = '\n'; 444 445 return len; 446 } 447 448 static IIO_DEV_ATTR_INT_TIME_AVAIL(zopt2201_show_int_time_available); 449 450 static ssize_t zopt2201_show_als_scale_avail(struct device *dev, 451 struct device_attribute *attr, 452 char *buf) 453 { 454 ssize_t len = 0; 455 int i; 456 457 for (i = 0; i < ARRAY_SIZE(zopt2201_scale_als); i++) 458 len += scnprintf(buf + len, PAGE_SIZE - len, "%d.%06u ", 459 zopt2201_scale_als[i].scale, 460 zopt2201_scale_als[i].uscale); 461 buf[len - 1] = '\n'; 462 463 return len; 464 } 465 466 static ssize_t zopt2201_show_uvb_scale_avail(struct device *dev, 467 struct device_attribute *attr, 468 char *buf) 469 { 470 ssize_t len = 0; 471 int i; 472 473 for (i = 0; i < ARRAY_SIZE(zopt2201_scale_uvb); i++) 474 len += scnprintf(buf + len, PAGE_SIZE - len, "%d.%06u ", 475 zopt2201_scale_uvb[i].scale, 476 zopt2201_scale_uvb[i].uscale); 477 buf[len - 1] = '\n'; 478 479 return len; 480 } 481 482 static IIO_DEVICE_ATTR(in_illuminance_scale_available, 0444, 483 zopt2201_show_als_scale_avail, NULL, 0); 484 static IIO_DEVICE_ATTR(in_intensity_uv_scale_available, 0444, 485 zopt2201_show_uvb_scale_avail, NULL, 0); 486 487 static struct attribute *zopt2201_attributes[] = { 488 &iio_dev_attr_integration_time_available.dev_attr.attr, 489 &iio_dev_attr_in_illuminance_scale_available.dev_attr.attr, 490 &iio_dev_attr_in_intensity_uv_scale_available.dev_attr.attr, 491 NULL 492 }; 493 494 static const struct attribute_group zopt2201_attribute_group = { 495 .attrs = zopt2201_attributes, 496 }; 497 498 static const struct iio_info zopt2201_info = { 499 .read_raw = zopt2201_read_raw, 500 .write_raw = zopt2201_write_raw, 501 .attrs = &zopt2201_attribute_group, 502 }; 503 504 static int zopt2201_probe(struct i2c_client *client) 505 { 506 struct zopt2201_data *data; 507 struct iio_dev *indio_dev; 508 int ret; 509 510 if (!i2c_check_functionality(client->adapter, 511 I2C_FUNC_SMBUS_READ_I2C_BLOCK)) 512 return -EOPNOTSUPP; 513 514 ret = i2c_smbus_read_byte_data(client, ZOPT2201_PART_ID); 515 if (ret < 0) 516 return ret; 517 if (ret != ZOPT2201_PART_NUMBER) 518 return -ENODEV; 519 520 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data)); 521 if (!indio_dev) 522 return -ENOMEM; 523 524 data = iio_priv(indio_dev); 525 i2c_set_clientdata(client, indio_dev); 526 data->client = client; 527 mutex_init(&data->lock); 528 529 indio_dev->info = &zopt2201_info; 530 indio_dev->channels = zopt2201_channels; 531 indio_dev->num_channels = ARRAY_SIZE(zopt2201_channels); 532 indio_dev->name = ZOPT2201_DRV_NAME; 533 indio_dev->modes = INDIO_DIRECT_MODE; 534 535 data->rate = ZOPT2201_MEAS_FREQ_100MS; 536 ret = zopt2201_set_resolution(data, ZOPT2201_MEAS_RES_18BIT); 537 if (ret < 0) 538 return ret; 539 540 ret = zopt2201_set_gain(data, ZOPT2201_LS_GAIN_3); 541 if (ret < 0) 542 return ret; 543 544 return devm_iio_device_register(&client->dev, indio_dev); 545 } 546 547 static const struct i2c_device_id zopt2201_id[] = { 548 { "zopt2201" }, 549 { } 550 }; 551 MODULE_DEVICE_TABLE(i2c, zopt2201_id); 552 553 static struct i2c_driver zopt2201_driver = { 554 .driver = { 555 .name = ZOPT2201_DRV_NAME, 556 }, 557 .probe = zopt2201_probe, 558 .id_table = zopt2201_id, 559 }; 560 561 module_i2c_driver(zopt2201_driver); 562 563 MODULE_AUTHOR("Peter Meerwald-Stadler <pmeerw@pmeerw.net>"); 564 MODULE_DESCRIPTION("IDT ZOPT2201 ambient light and UV B sensor driver"); 565 MODULE_LICENSE("GPL"); 566