drivers/staging/iio/light/isl29018.c

   1 /*
   2  * A iio driver for the light sensor ISL 29018.
   3  *
   4  * IIO driver for monitoring ambient light intensity in luxi, proximity
   5  * sensing and infrared sensing.
   6  *
   7  * Copyright (c) 2010, NVIDIA Corporation.
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful, but WITHOUT
  15  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  16  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  17  * more details.
  18  *
  19  * You should have received a copy of the GNU General Public License along
  20  * with this program; if not, write to the Free Software Foundation, Inc.,
  21  * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  22  */
  23
  24 #include <linux/module.h>
  25 #include <linux/i2c.h>
  26 #include <linux/err.h>
  27 #include <linux/mutex.h>
  28 #include <linux/delay.h>
  29 #include <linux/slab.h>
  30 #include "../iio.h"
  31
  32 #define CONVERSION_TIME_MS              100
  33
  34 #define ISL29018_REG_ADD_COMMAND1       0x00
  35 #define COMMMAND1_OPMODE_SHIFT          5
  36 #define COMMMAND1_OPMODE_MASK           (7 << COMMMAND1_OPMODE_SHIFT)
  37 #define COMMMAND1_OPMODE_POWER_DOWN     0
  38 #define COMMMAND1_OPMODE_ALS_ONCE       1
  39 #define COMMMAND1_OPMODE_IR_ONCE        2
  40 #define COMMMAND1_OPMODE_PROX_ONCE      3
  41
  42 #define ISL29018_REG_ADD_COMMANDII      0x01
  43 #define COMMANDII_RESOLUTION_SHIFT      2
  44 #define COMMANDII_RESOLUTION_MASK       (0x3 << COMMANDII_RESOLUTION_SHIFT)
  45
  46 #define COMMANDII_RANGE_SHIFT           0
  47 #define COMMANDII_RANGE_MASK            (0x3 << COMMANDII_RANGE_SHIFT)
  48
  49 #define COMMANDII_SCHEME_SHIFT          7
  50 #define COMMANDII_SCHEME_MASK           (0x1 << COMMANDII_SCHEME_SHIFT)
  51
  52 #define ISL29018_REG_ADD_DATA_LSB       0x02
  53 #define ISL29018_REG_ADD_DATA_MSB       0x03
  54 #define ISL29018_MAX_REGS               ISL29018_REG_ADD_DATA_MSB
  55
  56 struct isl29018_chip {
  57         struct iio_dev          *indio_dev;
  58         struct i2c_client       *client;
  59         struct mutex            lock;
  60         unsigned int            range;
  61         unsigned int            adc_bit;
  62         int                     prox_scheme;
  63         u8                      reg_cache[ISL29018_MAX_REGS];
  64 };
  65
  66 static int isl29018_write_data(struct i2c_client *client, u8 reg,
  67                         u8 val, u8 mask, u8 shift)
  68 {
  69         u8 regval;
  70         int ret = 0;
  71         struct isl29018_chip *chip = i2c_get_clientdata(client);
  72
  73         regval = chip->reg_cache[reg];
  74         regval &= ~mask;
  75         regval |= val << shift;
  76
  77         ret = i2c_smbus_write_byte_data(client, reg, regval);
  78         if (ret) {
  79                 dev_err(&client->dev, "Write to device fails status %x\n", ret);
  80                 return ret;
  81         }
  82         chip->reg_cache[reg] = regval;
  83
  84         return 0;
  85 }
  86
  87 static int isl29018_set_range(struct i2c_client *client, unsigned long range,
  88                 unsigned int *new_range)
  89 {
  90         static const unsigned long supp_ranges[] = {1000, 4000, 16000, 64000};
  91         int i;
  92
  93         for (i = 0; i < ARRAY_SIZE(supp_ranges); ++i) {
  94                 if (range <= supp_ranges[i]) {
  95                         *new_range = (unsigned int)supp_ranges[i];
  96                         break;
  97                 }
  98         }
  99
 100         if (i >= ARRAY_SIZE(supp_ranges))
 101                 return -EINVAL;
 102
 103         return isl29018_write_data(client, ISL29018_REG_ADD_COMMANDII,
 104                         i, COMMANDII_RANGE_MASK, COMMANDII_RANGE_SHIFT);
 105 }
 106
 107 static int isl29018_set_resolution(struct i2c_client *client,
 108                         unsigned long adcbit, unsigned int *conf_adc_bit)
 109 {
 110         static const unsigned long supp_adcbit[] = {16, 12, 8, 4};
 111         int i;
 112
 113         for (i = 0; i < ARRAY_SIZE(supp_adcbit); ++i) {
 114                 if (adcbit >= supp_adcbit[i]) {
 115                         *conf_adc_bit = (unsigned int)supp_adcbit[i];
 116                         break;
 117                 }
 118         }
 119
 120         if (i >= ARRAY_SIZE(supp_adcbit))
 121                 return -EINVAL;
 122
 123         return isl29018_write_data(client, ISL29018_REG_ADD_COMMANDII,
 124                         i, COMMANDII_RESOLUTION_MASK,
 125                         COMMANDII_RESOLUTION_SHIFT);
 126 }
 127
 128 static int isl29018_read_sensor_input(struct i2c_client *client, int mode)
 129 {
 130         int status;
 131         int lsb;
 132         int msb;
 133
 134         /* Set mode */
 135         status = isl29018_write_data(client, ISL29018_REG_ADD_COMMAND1,
 136                         mode, COMMMAND1_OPMODE_MASK, COMMMAND1_OPMODE_SHIFT);
 137         if (status) {
 138                 dev_err(&client->dev, "Error in setting operating mode\n");
 139                 return status;
 140         }
 141         msleep(CONVERSION_TIME_MS);
 142         lsb = i2c_smbus_read_byte_data(client, ISL29018_REG_ADD_DATA_LSB);
 143         if (lsb < 0) {
 144                 dev_err(&client->dev, "Error in reading LSB DATA\n");
 145                 return lsb;
 146         }
 147
 148         msb = i2c_smbus_read_byte_data(client, ISL29018_REG_ADD_DATA_MSB);
 149         if (msb < 0) {
 150                 dev_err(&client->dev, "Error in reading MSB DATA\n");
 151                 return msb;
 152         }
 153         dev_vdbg(&client->dev, "MSB 0x%x and LSB 0x%x\n", msb, lsb);
 154
 155         return (msb << 8) | lsb;
 156 }
 157
 158 static int isl29018_read_lux(struct i2c_client *client, int *lux)
 159 {
 160         int lux_data;
 161         struct isl29018_chip *chip = i2c_get_clientdata(client);
 162
 163         lux_data = isl29018_read_sensor_input(client,
 164                                 COMMMAND1_OPMODE_ALS_ONCE);
 165
 166         if (lux_data < 0)
 167                 return lux_data;
 168
 169         *lux = (lux_data * chip->range) >> chip->adc_bit;
 170
 171         return 0;
 172 }
 173
 174 static int isl29018_read_ir(struct i2c_client *client, int *ir)
 175 {
 176         int ir_data;
 177
 178         ir_data = isl29018_read_sensor_input(client, COMMMAND1_OPMODE_IR_ONCE);
 179
 180         if (ir_data < 0)
 181                 return ir_data;
 182
 183         *ir = ir_data;
 184
 185         return 0;
 186 }
 187
 188 static int isl29018_read_proximity_ir(struct i2c_client *client, int scheme,
 189                 int *near_ir)
 190 {
 191         int status;
 192         int prox_data = -1;
 193         int ir_data = -1;
 194
 195         /* Do proximity sensing with required scheme */
 196         status = isl29018_write_data(client, ISL29018_REG_ADD_COMMANDII,
 197                         scheme, COMMANDII_SCHEME_MASK, COMMANDII_SCHEME_SHIFT);
 198         if (status) {
 199                 dev_err(&client->dev, "Error in setting operating mode\n");
 200                 return status;
 201         }
 202
 203         prox_data = isl29018_read_sensor_input(client,
 204                                         COMMMAND1_OPMODE_PROX_ONCE);
 205         if (prox_data < 0)
 206                 return prox_data;
 207
 208         if (scheme == 1) {
 209                 *near_ir = prox_data;
 210                 return 0;
 211         }
 212
 213         ir_data = isl29018_read_sensor_input(client,
 214                                 COMMMAND1_OPMODE_IR_ONCE);
 215
 216         if (ir_data < 0)
 217                 return ir_data;
 218
 219         if (prox_data >= ir_data)
 220                 *near_ir = prox_data - ir_data;
 221         else
 222                 *near_ir = 0;
 223
 224         return 0;
 225 }
 226
 227 static ssize_t get_sensor_data(struct device *dev, char *buf, int mode)
 228 {
 229         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 230         struct isl29018_chip *chip = indio_dev->dev_data;
 231         struct i2c_client *client = chip->client;
 232         int value = 0;
 233         int status;
 234
 235         mutex_lock(&chip->lock);
 236         switch (mode) {
 237         case COMMMAND1_OPMODE_PROX_ONCE:
 238                 status = isl29018_read_proximity_ir(client,
 239                                 chip->prox_scheme, &value);
 240                 break;
 241
 242         case COMMMAND1_OPMODE_ALS_ONCE:
 243                 status = isl29018_read_lux(client, &value);
 244                 break;
 245
 246         case COMMMAND1_OPMODE_IR_ONCE:
 247                 status = isl29018_read_ir(client, &value);
 248                 break;
 249
 250         default:
 251                 dev_err(&client->dev, "Mode %d is not supported\n", mode);
 252                 mutex_unlock(&chip->lock);
 253                 return -EBUSY;
 254         }
 255         if (status < 0) {
 256                 dev_err(&client->dev, "Error in Reading data");
 257                 mutex_unlock(&chip->lock);
 258                 return status;
 259         }
 260
 261         mutex_unlock(&chip->lock);
 262
 263         return sprintf(buf, "%d\n", value);
 264 }
 265
 266 /* Sysfs interface */
 267 /* range */
 268 static ssize_t show_range(struct device *dev,
 269                         struct device_attribute *attr, char *buf)
 270 {
 271         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 272         struct isl29018_chip *chip = indio_dev->dev_data;
 273
 274         return sprintf(buf, "%u\n", chip->range);
 275 }
 276
 277 static ssize_t store_range(struct device *dev,
 278                 struct device_attribute *attr, const char *buf, size_t count)
 279 {
 280         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 281         struct isl29018_chip *chip = indio_dev->dev_data;
 282         struct i2c_client *client = chip->client;
 283         int status;
 284         unsigned long lval;
 285         unsigned int new_range;
 286
 287         if (strict_strtoul(buf, 10, &lval))
 288                 return -EINVAL;
 289
 290         if (!(lval == 1000UL || lval == 4000UL ||
 291                         lval == 16000UL || lval == 64000UL)) {
 292                 dev_err(dev, "The range is not supported\n");
 293                 return -EINVAL;
 294         }
 295
 296         mutex_lock(&chip->lock);
 297         status = isl29018_set_range(client, lval, &new_range);
 298         if (status < 0) {
 299                 mutex_unlock(&chip->lock);
 300                 dev_err(dev, "Error in setting max range\n");
 301                 return status;
 302         }
 303         chip->range = new_range;
 304         mutex_unlock(&chip->lock);
 305
 306         return count;
 307 }
 308
 309 /* resolution */
 310 static ssize_t show_resolution(struct device *dev,
 311                         struct device_attribute *attr, char *buf)
 312 {
 313         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 314         struct isl29018_chip *chip = indio_dev->dev_data;
 315
 316         return sprintf(buf, "%u\n", chip->adc_bit);
 317 }
 318
 319 static ssize_t store_resolution(struct device *dev,
 320                 struct device_attribute *attr, const char *buf, size_t count)
 321 {
 322         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 323         struct isl29018_chip *chip = indio_dev->dev_data;
 324         struct i2c_client *client = chip->client;
 325         int status;
 326         unsigned long lval;
 327         unsigned int new_adc_bit;
 328
 329         if (strict_strtoul(buf, 10, &lval))
 330                 return -EINVAL;
 331         if (!(lval == 4 || lval == 8 || lval == 12 || lval == 16)) {
 332                 dev_err(dev, "The resolution is not supported\n");
 333                 return -EINVAL;
 334         }
 335
 336         mutex_lock(&chip->lock);
 337         status = isl29018_set_resolution(client, lval, &new_adc_bit);
 338         if (status < 0) {
 339                 mutex_unlock(&chip->lock);
 340                 dev_err(dev, "Error in setting resolution\n");
 341                 return status;
 342         }
 343         chip->adc_bit = new_adc_bit;
 344         mutex_unlock(&chip->lock);
 345
 346         return count;
 347 }
 348
 349 /* proximity scheme */
 350 static ssize_t show_prox_infrared_supression(struct device *dev,
 351                         struct device_attribute *attr, char *buf)
 352 {
 353         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 354         struct isl29018_chip *chip = indio_dev->dev_data;
 355
 356         /* return the "proximity scheme" i.e. if the chip does on chip
 357         infrared supression (1 means perform on chip supression) */
 358         return sprintf(buf, "%d\n", chip->prox_scheme);
 359 }
 360
 361 static ssize_t store_prox_infrared_supression(struct device *dev,
 362                 struct device_attribute *attr, const char *buf, size_t count)
 363 {
 364         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 365         struct isl29018_chip *chip = indio_dev->dev_data;
 366         unsigned long lval;
 367
 368         if (strict_strtoul(buf, 10, &lval))
 369                 return -EINVAL;
 370         if (!(lval == 0UL || lval == 1UL)) {
 371                 dev_err(dev, "The mode is not supported\n");
 372                 return -EINVAL;
 373         }
 374
 375         /* get the  "proximity scheme" i.e. if the chip does on chip
 376         infrared supression (1 means perform on chip supression) */
 377         mutex_lock(&chip->lock);
 378         chip->prox_scheme = (int)lval;
 379         mutex_unlock(&chip->lock);
 380
 381         return count;
 382 }
 383
 384 /* Read lux */
 385 static ssize_t show_lux(struct device *dev,
 386                 struct device_attribute *devattr, char *buf)
 387 {
 388         return get_sensor_data(dev, buf, COMMMAND1_OPMODE_ALS_ONCE);
 389 }
 390
 391 /* Read ir */
 392 static ssize_t show_ir(struct device *dev,
 393                 struct device_attribute *devattr, char *buf)
 394 {
 395         return get_sensor_data(dev, buf, COMMMAND1_OPMODE_IR_ONCE);
 396 }
 397
 398 /* Read nearest ir */
 399 static ssize_t show_proxim_ir(struct device *dev,
 400                 struct device_attribute *devattr, char *buf)
 401 {
 402         return get_sensor_data(dev, buf, COMMMAND1_OPMODE_PROX_ONCE);
 403 }
 404
 405 static IIO_DEVICE_ATTR(range, S_IRUGO | S_IWUSR, show_range, store_range, 0);
 406 static IIO_CONST_ATTR(range_available, "1000 4000 16000 64000");
 407 static IIO_CONST_ATTR(adc_resolution_available, "4 8 12 16");
 408 static IIO_DEVICE_ATTR(adc_resolution, S_IRUGO | S_IWUSR,
 409                                         show_resolution, store_resolution, 0);
 410 static IIO_DEVICE_ATTR(proximity_on_chip_ambient_infrared_supression,
 411                                         S_IRUGO | S_IWUSR,
 412                                         show_prox_infrared_supression,
 413                                         store_prox_infrared_supression, 0);
 414 static IIO_DEVICE_ATTR(illuminance0_input, S_IRUGO, show_lux, NULL, 0);
 415 static IIO_DEVICE_ATTR(intensity_infrared_raw, S_IRUGO, show_ir, NULL, 0);
 416 static IIO_DEVICE_ATTR(proximity_raw, S_IRUGO, show_proxim_ir, NULL, 0);
 417
 418 #define ISL29018_DEV_ATTR(name) (&iio_dev_attr_##name.dev_attr.attr)
 419 #define ISL29018_CONST_ATTR(name) (&iio_const_attr_##name.dev_attr.attr)
 420 static struct attribute *isl29018_attributes[] = {
 421         ISL29018_DEV_ATTR(range),
 422         ISL29018_CONST_ATTR(range_available),
 423         ISL29018_DEV_ATTR(adc_resolution),
 424         ISL29018_CONST_ATTR(adc_resolution_available),
 425         ISL29018_DEV_ATTR(proximity_on_chip_ambient_infrared_supression),
 426         ISL29018_DEV_ATTR(illuminance0_input),
 427         ISL29018_DEV_ATTR(intensity_infrared_raw),
 428         ISL29018_DEV_ATTR(proximity_raw),
 429         NULL
 430 };
 431
 432 static const struct attribute_group isl29108_group = {
 433         .attrs = isl29018_attributes,
 434 };
 435
 436 static int isl29018_chip_init(struct i2c_client *client)
 437 {
 438         struct isl29018_chip *chip = i2c_get_clientdata(client);
 439         int status;
 440         int new_adc_bit;
 441         unsigned int new_range;
 442
 443         memset(chip->reg_cache, 0, sizeof(chip->reg_cache));
 444
 445         /* set defaults */
 446         status = isl29018_set_range(client, chip->range, &new_range);
 447         if (status < 0) {
 448                 dev_err(&client->dev, "Init of isl29018 fails\n");
 449                 return status;
 450         }
 451
 452         status = isl29018_set_resolution(client, chip->adc_bit,
 453                                                 &new_adc_bit);
 454
 455         return 0;
 456 }
 457
 458 static const struct iio_info isl29108_info = {
 459         .attrs = &isl29108_group,
 460         .driver_module = THIS_MODULE,
 461 };
 462
 463 static int __devinit isl29018_probe(struct i2c_client *client,
 464                          const struct i2c_device_id *id)
 465 {
 466         struct isl29018_chip *chip;
 467         int err;
 468
 469         chip = kzalloc(sizeof(struct isl29018_chip), GFP_KERNEL);
 470         if (!chip) {
 471                 dev_err(&client->dev, "Memory allocation fails\n");
 472                 err = -ENOMEM;
 473                 goto exit;
 474         }
 475
 476         i2c_set_clientdata(client, chip);
 477         chip->client = client;
 478
 479         mutex_init(&chip->lock);
 480
 481         chip->range = 1000;
 482         chip->adc_bit = 16;
 483
 484         err = isl29018_chip_init(client);
 485         if (err)
 486                 goto exit_free;
 487
 488         chip->indio_dev = iio_allocate_device(0);
 489         if (!chip->indio_dev) {
 490                 dev_err(&client->dev, "iio allocation fails\n");
 491                 goto exit_free;
 492         }
 493         chip->indio_dev->info = &isl29108_info;
 494         chip->indio_dev->name = id->name;
 495         chip->indio_dev->dev.parent = &client->dev;
 496         chip->indio_dev->dev_data = (void *)(chip);
 497         chip->indio_dev->modes = INDIO_DIRECT_MODE;
 498         err = iio_device_register(chip->indio_dev);
 499         if (err) {
 500                 dev_err(&client->dev, "iio registration fails\n");
 501                 goto exit_iio_free;
 502         }
 503
 504         return 0;
 505 exit_iio_free:
 506         iio_free_device(chip->indio_dev);
 507 exit_free:
 508         kfree(chip);
 509 exit:
 510         return err;
 511 }
 512
 513 static int __devexit isl29018_remove(struct i2c_client *client)
 514 {
 515         struct isl29018_chip *chip = i2c_get_clientdata(client);
 516
 517         dev_dbg(&client->dev, "%s()\n", __func__);
 518         iio_device_unregister(chip->indio_dev);
 519         kfree(chip);
 520
 521         return 0;
 522 }
 523
 524 static const struct i2c_device_id isl29018_id[] = {
 525         {"isl29018", 0},
 526         {}
 527 };
 528
 529 MODULE_DEVICE_TABLE(i2c, isl29018_id);
 530
 531 static struct i2c_driver isl29018_driver = {
 532         .class  = I2C_CLASS_HWMON,
 533         .driver  = {
 534                         .name = "isl29018",
 535                         .owner = THIS_MODULE,
 536                     },
 537         .probe   = isl29018_probe,
 538         .remove  = __devexit_p(isl29018_remove),
 539         .id_table = isl29018_id,
 540 };
 541
 542 static int __init isl29018_init(void)
 543 {
 544         return i2c_add_driver(&isl29018_driver);
 545 }
 546
 547 static void __exit isl29018_exit(void)
 548 {
 549         i2c_del_driver(&isl29018_driver);
 550 }
 551
 552 module_init(isl29018_init);
 553 module_exit(isl29018_exit);
 554
 555 MODULE_DESCRIPTION("ISL29018 Ambient Light Sensor driver");
 556 MODULE_LICENSE("GPL");