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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * zopt2201.c - Support for IDT ZOPT2201 ambient light and UV B sensor4 *5 * Copyright 2017 Peter Meerwald-Stadler <pmeerw@pmeerw.net>6 *7 * Datasheet: https://www.idt.com/document/dst/zopt2201-datasheet8 * 7-bit I2C slave addresses 0x53 (default) or 0x52 (programmed)9 *10 * TODO: interrupt support, ALS/UVB raw mode11 */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 0x0028#define ZOPT2201_LS_MEAS_RATE 0x0429#define ZOPT2201_LS_GAIN 0x0530#define ZOPT2201_PART_ID 0x0631#define ZOPT2201_MAIN_STATUS 0x0732#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 0x1937#define ZOPT2201_INT_PST 0x1a38 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 450 51/* Values for ZOPT2201_LS_MEAS_RATE measurement rate */52#define ZOPT2201_MEAS_FREQ_25MS 053#define ZOPT2201_MEAS_FREQ_50MS 154#define ZOPT2201_MEAS_FREQ_100MS 2 /* default */55#define ZOPT2201_MEAS_FREQ_200MS 356#define ZOPT2201_MEAS_FREQ_500MS 457#define ZOPT2201_MEAS_FREQ_1000MS 558#define ZOPT2201_MEAS_FREQ_2000MS 659 60/* Values for ZOPT2201_LS_GAIN */61#define ZOPT2201_LS_GAIN_1 062#define ZOPT2201_LS_GAIN_3 163#define ZOPT2201_LS_GAIN_6 264#define ZOPT2201_LS_GAIN_9 365#define ZOPT2201_LS_GAIN_18 466 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 0xb273 74struct zopt2201_data {75 struct i2c_client *client;76 struct mutex lock;77 u8 gain;78 u8 res;79 u8 rate;80};81 82static 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 93static 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 104static 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 116static 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 145static 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 174static 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 184static 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 else202 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 226fail:227 mutex_unlock(&data->lock);228 return ret;229}230 231static 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 254static 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 304static 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 319static 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 338static 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 351static 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 362unlock:363 mutex_unlock(&data->lock);364 return ret;365}366 367static 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 381static 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 392unlock:393 mutex_unlock(&data->lock);394 return ret;395}396 397static 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 410static 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 433static 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 448static IIO_DEV_ATTR_INT_TIME_AVAIL(zopt2201_show_int_time_available);449 450static 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 466static 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 482static IIO_DEVICE_ATTR(in_illuminance_scale_available, 0444,483 zopt2201_show_als_scale_avail, NULL, 0);484static IIO_DEVICE_ATTR(in_intensity_uv_scale_available, 0444,485 zopt2201_show_uvb_scale_avail, NULL, 0);486 487static 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 NULL492};493 494static const struct attribute_group zopt2201_attribute_group = {495 .attrs = zopt2201_attributes,496};497 498static 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 504static 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 547static const struct i2c_device_id zopt2201_id[] = {548 { "zopt2201" },549 { }550};551MODULE_DEVICE_TABLE(i2c, zopt2201_id);552 553static struct i2c_driver zopt2201_driver = {554 .driver = {555 .name = ZOPT2201_DRV_NAME,556 },557 .probe = zopt2201_probe,558 .id_table = zopt2201_id,559};560 561module_i2c_driver(zopt2201_driver);562 563MODULE_AUTHOR("Peter Meerwald-Stadler <pmeerw@pmeerw.net>");564MODULE_DESCRIPTION("IDT ZOPT2201 ambient light and UV B sensor driver");565MODULE_LICENSE("GPL");566