1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * apds9300.c - IIO driver for Avago APDS9300 ambient light sensor 4 * 5 * Copyright 2013 Oleksandr Kravchenko <o.v.kravchenko@globallogic.com> 6 */ 7 8 #include <linux/module.h> 9 #include <linux/slab.h> 10 #include <linux/pm.h> 11 #include <linux/i2c.h> 12 #include <linux/err.h> 13 #include <linux/mutex.h> 14 #include <linux/interrupt.h> 15 #include <linux/iio/iio.h> 16 #include <linux/iio/sysfs.h> 17 #include <linux/iio/events.h> 18 19 #define APDS9300_DRV_NAME "apds9300" 20 #define APDS9300_IRQ_NAME "apds9300_event" 21 22 /* Command register bits */ 23 #define APDS9300_CMD BIT(7) /* Select command register. Must write as 1 */ 24 #define APDS9300_WORD BIT(5) /* I2C write/read: if 1 word, if 0 byte */ 25 #define APDS9300_CLEAR BIT(6) /* Interrupt clear. Clears pending interrupt */ 26 27 /* Register set */ 28 #define APDS9300_CONTROL 0x00 /* Control of basic functions */ 29 #define APDS9300_THRESHLOWLOW 0x02 /* Low byte of low interrupt threshold */ 30 #define APDS9300_THRESHHIGHLOW 0x04 /* Low byte of high interrupt threshold */ 31 #define APDS9300_INTERRUPT 0x06 /* Interrupt control */ 32 #define APDS9300_DATA0LOW 0x0c /* Low byte of ADC channel 0 */ 33 #define APDS9300_DATA1LOW 0x0e /* Low byte of ADC channel 1 */ 34 35 /* Power on/off value for APDS9300_CONTROL register */ 36 #define APDS9300_POWER_ON 0x03 37 #define APDS9300_POWER_OFF 0x00 38 39 /* Interrupts */ 40 #define APDS9300_INTR_ENABLE 0x10 41 /* Interrupt Persist Function: Any value outside of threshold range */ 42 #define APDS9300_THRESH_INTR 0x01 43 44 #define APDS9300_THRESH_MAX 0xffff /* Max threshold value */ 45 46 struct apds9300_data { 47 struct i2c_client *client; 48 struct mutex mutex; 49 int power_state; 50 int thresh_low; 51 int thresh_hi; 52 int intr_en; 53 }; 54 55 /* Lux calculation */ 56 57 /* Calculated values 1000 * (CH1/CH0)^1.4 for CH1/CH0 from 0 to 0.52 */ 58 static const u16 apds9300_lux_ratio[] = { 59 0, 2, 4, 7, 11, 15, 19, 24, 29, 34, 40, 45, 51, 57, 64, 70, 77, 84, 91, 60 98, 105, 112, 120, 128, 136, 144, 152, 160, 168, 177, 185, 194, 203, 61 212, 221, 230, 239, 249, 258, 268, 277, 287, 297, 307, 317, 327, 337, 62 347, 358, 368, 379, 390, 400, 63 }; 64 65 static unsigned long apds9300_calculate_lux(u16 ch0, u16 ch1) 66 { 67 unsigned long lux, tmp; 68 69 /* avoid division by zero */ 70 if (ch0 == 0) 71 return 0; 72 73 tmp = DIV_ROUND_UP(ch1 * 100, ch0); 74 if (tmp <= 52) { 75 lux = 3150 * ch0 - (unsigned long)DIV_ROUND_UP_ULL(ch0 76 * apds9300_lux_ratio[tmp] * 5930ull, 1000); 77 } else if (tmp <= 65) { 78 lux = 2290 * ch0 - 2910 * ch1; 79 } else if (tmp <= 80) { 80 lux = 1570 * ch0 - 1800 * ch1; 81 } else if (tmp <= 130) { 82 lux = 338 * ch0 - 260 * ch1; 83 } else { 84 lux = 0; 85 } 86 87 return lux / 100000; 88 } 89 90 static int apds9300_get_adc_val(struct apds9300_data *data, int adc_number) 91 { 92 int ret; 93 u8 flags = APDS9300_CMD | APDS9300_WORD; 94 95 if (!data->power_state) 96 return -EBUSY; 97 98 /* Select ADC0 or ADC1 data register */ 99 flags |= adc_number ? APDS9300_DATA1LOW : APDS9300_DATA0LOW; 100 101 ret = i2c_smbus_read_word_data(data->client, flags); 102 if (ret < 0) 103 dev_err(&data->client->dev, 104 "failed to read ADC%d value\n", adc_number); 105 106 return ret; 107 } 108 109 static int apds9300_set_thresh_low(struct apds9300_data *data, int value) 110 { 111 int ret; 112 113 if (!data->power_state) 114 return -EBUSY; 115 116 if (value > APDS9300_THRESH_MAX) 117 return -EINVAL; 118 119 ret = i2c_smbus_write_word_data(data->client, APDS9300_THRESHLOWLOW 120 | APDS9300_CMD | APDS9300_WORD, value); 121 if (ret) { 122 dev_err(&data->client->dev, "failed to set thresh_low\n"); 123 return ret; 124 } 125 data->thresh_low = value; 126 127 return 0; 128 } 129 130 static int apds9300_set_thresh_hi(struct apds9300_data *data, int value) 131 { 132 int ret; 133 134 if (!data->power_state) 135 return -EBUSY; 136 137 if (value > APDS9300_THRESH_MAX) 138 return -EINVAL; 139 140 ret = i2c_smbus_write_word_data(data->client, APDS9300_THRESHHIGHLOW 141 | APDS9300_CMD | APDS9300_WORD, value); 142 if (ret) { 143 dev_err(&data->client->dev, "failed to set thresh_hi\n"); 144 return ret; 145 } 146 data->thresh_hi = value; 147 148 return 0; 149 } 150 151 static int apds9300_set_intr_state(struct apds9300_data *data, int state) 152 { 153 int ret; 154 u8 cmd; 155 156 if (!data->power_state) 157 return -EBUSY; 158 159 cmd = state ? APDS9300_INTR_ENABLE | APDS9300_THRESH_INTR : 0x00; 160 ret = i2c_smbus_write_byte_data(data->client, 161 APDS9300_INTERRUPT | APDS9300_CMD, cmd); 162 if (ret) { 163 dev_err(&data->client->dev, 164 "failed to set interrupt state %d\n", state); 165 return ret; 166 } 167 data->intr_en = state; 168 169 return 0; 170 } 171 172 static int apds9300_set_power_state(struct apds9300_data *data, int state) 173 { 174 int ret; 175 u8 cmd; 176 177 cmd = state ? APDS9300_POWER_ON : APDS9300_POWER_OFF; 178 ret = i2c_smbus_write_byte_data(data->client, 179 APDS9300_CONTROL | APDS9300_CMD, cmd); 180 if (ret) { 181 dev_err(&data->client->dev, 182 "failed to set power state %d\n", state); 183 return ret; 184 } 185 data->power_state = state; 186 187 return 0; 188 } 189 190 static void apds9300_clear_intr(struct apds9300_data *data) 191 { 192 int ret; 193 194 ret = i2c_smbus_write_byte(data->client, APDS9300_CLEAR | APDS9300_CMD); 195 if (ret < 0) 196 dev_err(&data->client->dev, "failed to clear interrupt\n"); 197 } 198 199 static int apds9300_chip_init(struct apds9300_data *data) 200 { 201 int ret; 202 203 /* Need to set power off to ensure that the chip is off */ 204 ret = apds9300_set_power_state(data, 0); 205 if (ret < 0) 206 goto err; 207 /* 208 * Probe the chip. To do so we try to power up the device and then to 209 * read back the 0x03 code 210 */ 211 ret = apds9300_set_power_state(data, 1); 212 if (ret < 0) 213 goto err; 214 ret = i2c_smbus_read_byte_data(data->client, 215 APDS9300_CONTROL | APDS9300_CMD); 216 if (ret != APDS9300_POWER_ON) { 217 ret = -ENODEV; 218 goto err; 219 } 220 /* 221 * Disable interrupt to ensure thai it is doesn't enable 222 * i.e. after device soft reset 223 */ 224 ret = apds9300_set_intr_state(data, 0); 225 if (ret < 0) 226 goto err; 227 228 return 0; 229 230 err: 231 dev_err(&data->client->dev, "failed to init the chip\n"); 232 return ret; 233 } 234 235 static int apds9300_read_raw(struct iio_dev *indio_dev, 236 struct iio_chan_spec const *chan, int *val, int *val2, 237 long mask) 238 { 239 int ch0, ch1, ret = -EINVAL; 240 struct apds9300_data *data = iio_priv(indio_dev); 241 242 mutex_lock(&data->mutex); 243 switch (chan->type) { 244 case IIO_LIGHT: 245 ch0 = apds9300_get_adc_val(data, 0); 246 if (ch0 < 0) { 247 ret = ch0; 248 break; 249 } 250 ch1 = apds9300_get_adc_val(data, 1); 251 if (ch1 < 0) { 252 ret = ch1; 253 break; 254 } 255 *val = apds9300_calculate_lux(ch0, ch1); 256 ret = IIO_VAL_INT; 257 break; 258 case IIO_INTENSITY: 259 ret = apds9300_get_adc_val(data, chan->channel); 260 if (ret < 0) 261 break; 262 *val = ret; 263 ret = IIO_VAL_INT; 264 break; 265 default: 266 break; 267 } 268 mutex_unlock(&data->mutex); 269 270 return ret; 271 } 272 273 static int apds9300_read_thresh(struct iio_dev *indio_dev, 274 const struct iio_chan_spec *chan, enum iio_event_type type, 275 enum iio_event_direction dir, enum iio_event_info info, 276 int *val, int *val2) 277 { 278 struct apds9300_data *data = iio_priv(indio_dev); 279 280 switch (dir) { 281 case IIO_EV_DIR_RISING: 282 *val = data->thresh_hi; 283 break; 284 case IIO_EV_DIR_FALLING: 285 *val = data->thresh_low; 286 break; 287 default: 288 return -EINVAL; 289 } 290 291 return IIO_VAL_INT; 292 } 293 294 static int apds9300_write_thresh(struct iio_dev *indio_dev, 295 const struct iio_chan_spec *chan, enum iio_event_type type, 296 enum iio_event_direction dir, enum iio_event_info info, int val, 297 int val2) 298 { 299 struct apds9300_data *data = iio_priv(indio_dev); 300 int ret; 301 302 mutex_lock(&data->mutex); 303 if (dir == IIO_EV_DIR_RISING) 304 ret = apds9300_set_thresh_hi(data, val); 305 else 306 ret = apds9300_set_thresh_low(data, val); 307 mutex_unlock(&data->mutex); 308 309 return ret; 310 } 311 312 static int apds9300_read_interrupt_config(struct iio_dev *indio_dev, 313 const struct iio_chan_spec *chan, 314 enum iio_event_type type, 315 enum iio_event_direction dir) 316 { 317 struct apds9300_data *data = iio_priv(indio_dev); 318 319 return data->intr_en; 320 } 321 322 static int apds9300_write_interrupt_config(struct iio_dev *indio_dev, 323 const struct iio_chan_spec *chan, enum iio_event_type type, 324 enum iio_event_direction dir, int state) 325 { 326 struct apds9300_data *data = iio_priv(indio_dev); 327 int ret; 328 329 mutex_lock(&data->mutex); 330 ret = apds9300_set_intr_state(data, state); 331 mutex_unlock(&data->mutex); 332 333 return ret; 334 } 335 336 static const struct iio_info apds9300_info_no_irq = { 337 .read_raw = apds9300_read_raw, 338 }; 339 340 static const struct iio_info apds9300_info = { 341 .read_raw = apds9300_read_raw, 342 .read_event_value = apds9300_read_thresh, 343 .write_event_value = apds9300_write_thresh, 344 .read_event_config = apds9300_read_interrupt_config, 345 .write_event_config = apds9300_write_interrupt_config, 346 }; 347 348 static const struct iio_event_spec apds9300_event_spec[] = { 349 { 350 .type = IIO_EV_TYPE_THRESH, 351 .dir = IIO_EV_DIR_RISING, 352 .mask_separate = BIT(IIO_EV_INFO_VALUE) | 353 BIT(IIO_EV_INFO_ENABLE), 354 }, { 355 .type = IIO_EV_TYPE_THRESH, 356 .dir = IIO_EV_DIR_FALLING, 357 .mask_separate = BIT(IIO_EV_INFO_VALUE) | 358 BIT(IIO_EV_INFO_ENABLE), 359 }, 360 }; 361 362 static const struct iio_chan_spec apds9300_channels[] = { 363 { 364 .type = IIO_LIGHT, 365 .channel = 0, 366 .indexed = true, 367 .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED), 368 }, { 369 .type = IIO_INTENSITY, 370 .channel = 0, 371 .channel2 = IIO_MOD_LIGHT_BOTH, 372 .indexed = true, 373 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), 374 .event_spec = apds9300_event_spec, 375 .num_event_specs = ARRAY_SIZE(apds9300_event_spec), 376 }, { 377 .type = IIO_INTENSITY, 378 .channel = 1, 379 .channel2 = IIO_MOD_LIGHT_IR, 380 .indexed = true, 381 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), 382 }, 383 }; 384 385 static irqreturn_t apds9300_interrupt_handler(int irq, void *private) 386 { 387 struct iio_dev *dev_info = private; 388 struct apds9300_data *data = iio_priv(dev_info); 389 390 iio_push_event(dev_info, 391 IIO_UNMOD_EVENT_CODE(IIO_INTENSITY, 0, 392 IIO_EV_TYPE_THRESH, 393 IIO_EV_DIR_EITHER), 394 iio_get_time_ns(dev_info)); 395 396 apds9300_clear_intr(data); 397 398 return IRQ_HANDLED; 399 } 400 401 static int apds9300_probe(struct i2c_client *client, 402 const struct i2c_device_id *id) 403 { 404 struct apds9300_data *data; 405 struct iio_dev *indio_dev; 406 int ret; 407 408 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data)); 409 if (!indio_dev) 410 return -ENOMEM; 411 412 data = iio_priv(indio_dev); 413 i2c_set_clientdata(client, indio_dev); 414 data->client = client; 415 416 ret = apds9300_chip_init(data); 417 if (ret < 0) 418 goto err; 419 420 mutex_init(&data->mutex); 421 422 indio_dev->channels = apds9300_channels; 423 indio_dev->num_channels = ARRAY_SIZE(apds9300_channels); 424 indio_dev->name = APDS9300_DRV_NAME; 425 indio_dev->modes = INDIO_DIRECT_MODE; 426 427 if (client->irq) 428 indio_dev->info = &apds9300_info; 429 else 430 indio_dev->info = &apds9300_info_no_irq; 431 432 if (client->irq) { 433 ret = devm_request_threaded_irq(&client->dev, client->irq, 434 NULL, apds9300_interrupt_handler, 435 IRQF_TRIGGER_FALLING | IRQF_ONESHOT, 436 APDS9300_IRQ_NAME, indio_dev); 437 if (ret) { 438 dev_err(&client->dev, "irq request error %d\n", -ret); 439 goto err; 440 } 441 } 442 443 ret = iio_device_register(indio_dev); 444 if (ret < 0) 445 goto err; 446 447 return 0; 448 449 err: 450 /* Ensure that power off in case of error */ 451 apds9300_set_power_state(data, 0); 452 return ret; 453 } 454 455 static void apds9300_remove(struct i2c_client *client) 456 { 457 struct iio_dev *indio_dev = i2c_get_clientdata(client); 458 struct apds9300_data *data = iio_priv(indio_dev); 459 460 iio_device_unregister(indio_dev); 461 462 /* Ensure that power off and interrupts are disabled */ 463 apds9300_set_intr_state(data, 0); 464 apds9300_set_power_state(data, 0); 465 } 466 467 static int apds9300_suspend(struct device *dev) 468 { 469 struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev)); 470 struct apds9300_data *data = iio_priv(indio_dev); 471 int ret; 472 473 mutex_lock(&data->mutex); 474 ret = apds9300_set_power_state(data, 0); 475 mutex_unlock(&data->mutex); 476 477 return ret; 478 } 479 480 static int apds9300_resume(struct device *dev) 481 { 482 struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev)); 483 struct apds9300_data *data = iio_priv(indio_dev); 484 int ret; 485 486 mutex_lock(&data->mutex); 487 ret = apds9300_set_power_state(data, 1); 488 mutex_unlock(&data->mutex); 489 490 return ret; 491 } 492 493 static DEFINE_SIMPLE_DEV_PM_OPS(apds9300_pm_ops, apds9300_suspend, 494 apds9300_resume); 495 496 static const struct i2c_device_id apds9300_id[] = { 497 { APDS9300_DRV_NAME, 0 }, 498 { } 499 }; 500 501 MODULE_DEVICE_TABLE(i2c, apds9300_id); 502 503 static struct i2c_driver apds9300_driver = { 504 .driver = { 505 .name = APDS9300_DRV_NAME, 506 .pm = pm_sleep_ptr(&apds9300_pm_ops), 507 }, 508 .probe = apds9300_probe, 509 .remove = apds9300_remove, 510 .id_table = apds9300_id, 511 }; 512 513 module_i2c_driver(apds9300_driver); 514 515 MODULE_AUTHOR("Kravchenko Oleksandr <o.v.kravchenko@globallogic.com>"); 516 MODULE_AUTHOR("GlobalLogic inc."); 517 MODULE_DESCRIPTION("APDS9300 ambient light photo sensor driver"); 518 MODULE_LICENSE("GPL"); 519