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