drivers/iio/light/tcs3414.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * tcs3414.c - Support for TAOS TCS3414 digital color sensor
   4  *
   5  * Copyright (c) 2014 Peter Meerwald <pmeerw@pmeerw.net>
   6  *
   7  * Digital color sensor with 16-bit channels for red, green, blue, clear);
   8  * 7-bit I2C slave address 0x39 (TCS3414) or 0x29, 0x49, 0x59 (TCS3413,
   9  * TCS3415, TCS3416, resp.)
  10  *
  11  * TODO: sync, interrupt support, thresholds, prescaler
  12  */
  13
  14 #include <linux/module.h>
  15 #include <linux/i2c.h>
  16 #include <linux/delay.h>
  17 #include <linux/pm.h>
  18
  19 #include <linux/iio/iio.h>
  20 #include <linux/iio/sysfs.h>
  21 #include <linux/iio/trigger_consumer.h>
  22 #include <linux/iio/buffer.h>
  23 #include <linux/iio/triggered_buffer.h>
  24
  25 #define TCS3414_DRV_NAME "tcs3414"
  26
  27 #define TCS3414_COMMAND BIT(7)
  28 #define TCS3414_COMMAND_WORD (TCS3414_COMMAND | BIT(5))
  29
  30 #define TCS3414_CONTROL (TCS3414_COMMAND | 0x00)
  31 #define TCS3414_TIMING (TCS3414_COMMAND | 0x01)
  32 #define TCS3414_ID (TCS3414_COMMAND | 0x04)
  33 #define TCS3414_GAIN (TCS3414_COMMAND | 0x07)
  34 #define TCS3414_DATA_GREEN (TCS3414_COMMAND_WORD | 0x10)
  35 #define TCS3414_DATA_RED (TCS3414_COMMAND_WORD | 0x12)
  36 #define TCS3414_DATA_BLUE (TCS3414_COMMAND_WORD | 0x14)
  37 #define TCS3414_DATA_CLEAR (TCS3414_COMMAND_WORD | 0x16)
  38
  39 #define TCS3414_CONTROL_ADC_VALID BIT(4)
  40 #define TCS3414_CONTROL_ADC_EN BIT(1)
  41 #define TCS3414_CONTROL_POWER BIT(0)
  42
  43 #define TCS3414_INTEG_MASK GENMASK(1, 0)
  44 #define TCS3414_INTEG_12MS 0x0
  45 #define TCS3414_INTEG_100MS 0x1
  46 #define TCS3414_INTEG_400MS 0x2
  47
  48 #define TCS3414_GAIN_MASK GENMASK(5, 4)
  49 #define TCS3414_GAIN_SHIFT 4
  50
  51 struct tcs3414_data {
  52         struct i2c_client *client;
  53         u8 control;
  54         u8 gain;
  55         u8 timing;
  56         u16 buffer[8]; /* 4x 16-bit + 8 bytes timestamp */
  57 };
  58
  59 #define TCS3414_CHANNEL(_color, _si, _addr) { \
  60         .type = IIO_INTENSITY, \
  61         .modified = 1, \
  62         .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
  63         .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \
  64                 BIT(IIO_CHAN_INFO_INT_TIME), \
  65         .channel2 = IIO_MOD_LIGHT_##_color, \
  66         .address = _addr, \
  67         .scan_index = _si, \
  68         .scan_type = { \
  69                 .sign = 'u', \
  70                 .realbits = 16, \
  71                 .storagebits = 16, \
  72                 .endianness = IIO_CPU, \
  73         }, \
  74 }
  75
  76 /* scale factors: 1/gain */
  77 static const int tcs3414_scales[][2] = {
  78         {1, 0}, {0, 250000}, {0, 62500}, {0, 15625}
  79 };
  80
  81 /* integration time in ms */
  82 static const int tcs3414_times[] = { 12, 100, 400 };
  83
  84 static const struct iio_chan_spec tcs3414_channels[] = {
  85         TCS3414_CHANNEL(GREEN, 0, TCS3414_DATA_GREEN),
  86         TCS3414_CHANNEL(RED, 1, TCS3414_DATA_RED),
  87         TCS3414_CHANNEL(BLUE, 2, TCS3414_DATA_BLUE),
  88         TCS3414_CHANNEL(CLEAR, 3, TCS3414_DATA_CLEAR),
  89         IIO_CHAN_SOFT_TIMESTAMP(4),
  90 };
  91
  92 static int tcs3414_req_data(struct tcs3414_data *data)
  93 {
  94         int tries = 25;
  95         int ret;
  96
  97         ret = i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL,
  98                 data->control | TCS3414_CONTROL_ADC_EN);
  99         if (ret < 0)
 100                 return ret;
 101
 102         while (tries--) {
 103                 ret = i2c_smbus_read_byte_data(data->client, TCS3414_CONTROL);
 104                 if (ret < 0)
 105                         return ret;
 106                 if (ret & TCS3414_CONTROL_ADC_VALID)
 107                         break;
 108                 msleep(20);
 109         }
 110
 111         ret = i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL,
 112                 data->control);
 113         if (ret < 0)
 114                 return ret;
 115
 116         if (tries < 0) {
 117                 dev_err(&data->client->dev, "data not ready\n");
 118                 return -EIO;
 119         }
 120
 121         return 0;
 122 }
 123
 124 static int tcs3414_read_raw(struct iio_dev *indio_dev,
 125                            struct iio_chan_spec const *chan,
 126                            int *val, int *val2, long mask)
 127 {
 128         struct tcs3414_data *data = iio_priv(indio_dev);
 129         int i, ret;
 130
 131         switch (mask) {
 132         case IIO_CHAN_INFO_RAW:
 133                 ret = iio_device_claim_direct_mode(indio_dev);
 134                 if (ret)
 135                         return ret;
 136                 ret = tcs3414_req_data(data);
 137                 if (ret < 0) {
 138                         iio_device_release_direct_mode(indio_dev);
 139                         return ret;
 140                 }
 141                 ret = i2c_smbus_read_word_data(data->client, chan->address);
 142                 iio_device_release_direct_mode(indio_dev);
 143                 if (ret < 0)
 144                         return ret;
 145                 *val = ret;
 146                 return IIO_VAL_INT;
 147         case IIO_CHAN_INFO_SCALE:
 148                 i = (data->gain & TCS3414_GAIN_MASK) >> TCS3414_GAIN_SHIFT;
 149                 *val = tcs3414_scales[i][0];
 150                 *val2 = tcs3414_scales[i][1];
 151                 return IIO_VAL_INT_PLUS_MICRO;
 152         case IIO_CHAN_INFO_INT_TIME:
 153                 *val = 0;
 154                 *val2 = tcs3414_times[data->timing & TCS3414_INTEG_MASK] * 1000;
 155                 return IIO_VAL_INT_PLUS_MICRO;
 156         }
 157         return -EINVAL;
 158 }
 159
 160 static int tcs3414_write_raw(struct iio_dev *indio_dev,
 161                                struct iio_chan_spec const *chan,
 162                                int val, int val2, long mask)
 163 {
 164         struct tcs3414_data *data = iio_priv(indio_dev);
 165         int i;
 166
 167         switch (mask) {
 168         case IIO_CHAN_INFO_SCALE:
 169                 for (i = 0; i < ARRAY_SIZE(tcs3414_scales); i++) {
 170                         if (val == tcs3414_scales[i][0] &&
 171                                 val2 == tcs3414_scales[i][1]) {
 172                                 data->gain &= ~TCS3414_GAIN_MASK;
 173                                 data->gain |= i << TCS3414_GAIN_SHIFT;
 174                                 return i2c_smbus_write_byte_data(
 175                                         data->client, TCS3414_GAIN,
 176                                         data->gain);
 177                         }
 178                 }
 179                 return -EINVAL;
 180         case IIO_CHAN_INFO_INT_TIME:
 181                 if (val != 0)
 182                         return -EINVAL;
 183                 for (i = 0; i < ARRAY_SIZE(tcs3414_times); i++) {
 184                         if (val2 == tcs3414_times[i] * 1000) {
 185                                 data->timing &= ~TCS3414_INTEG_MASK;
 186                                 data->timing |= i;
 187                                 return i2c_smbus_write_byte_data(
 188                                         data->client, TCS3414_TIMING,
 189                                         data->timing);
 190                         }
 191                 }
 192                 return -EINVAL;
 193         default:
 194                 return -EINVAL;
 195         }
 196 }
 197
 198 static irqreturn_t tcs3414_trigger_handler(int irq, void *p)
 199 {
 200         struct iio_poll_func *pf = p;
 201         struct iio_dev *indio_dev = pf->indio_dev;
 202         struct tcs3414_data *data = iio_priv(indio_dev);
 203         int i, j = 0;
 204
 205         for_each_set_bit(i, indio_dev->active_scan_mask,
 206                 indio_dev->masklength) {
 207                 int ret = i2c_smbus_read_word_data(data->client,
 208                         TCS3414_DATA_GREEN + 2*i);
 209                 if (ret < 0)
 210                         goto done;
 211
 212                 data->buffer[j++] = ret;
 213         }
 214
 215         iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
 216                 iio_get_time_ns(indio_dev));
 217
 218 done:
 219         iio_trigger_notify_done(indio_dev->trig);
 220
 221         return IRQ_HANDLED;
 222 }
 223
 224 static IIO_CONST_ATTR(scale_available, "1 0.25 0.0625 0.015625");
 225 static IIO_CONST_ATTR_INT_TIME_AVAIL("0.012 0.1 0.4");
 226
 227 static struct attribute *tcs3414_attributes[] = {
 228         &iio_const_attr_scale_available.dev_attr.attr,
 229         &iio_const_attr_integration_time_available.dev_attr.attr,
 230         NULL
 231 };
 232
 233 static const struct attribute_group tcs3414_attribute_group = {
 234         .attrs = tcs3414_attributes,
 235 };
 236
 237 static const struct iio_info tcs3414_info = {
 238         .read_raw = tcs3414_read_raw,
 239         .write_raw = tcs3414_write_raw,
 240         .attrs = &tcs3414_attribute_group,
 241 };
 242
 243 static int tcs3414_buffer_postenable(struct iio_dev *indio_dev)
 244 {
 245         struct tcs3414_data *data = iio_priv(indio_dev);
 246         int ret;
 247
 248         ret = iio_triggered_buffer_postenable(indio_dev);
 249         if (ret)
 250                 return ret;
 251
 252         data->control |= TCS3414_CONTROL_ADC_EN;
 253         ret = i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL,
 254                 data->control);
 255         if (ret)
 256                 iio_triggered_buffer_predisable(indio_dev);
 257
 258         return ret;
 259 }
 260
 261 static int tcs3414_buffer_predisable(struct iio_dev *indio_dev)
 262 {
 263         struct tcs3414_data *data = iio_priv(indio_dev);
 264         int ret, ret2;
 265
 266         data->control &= ~TCS3414_CONTROL_ADC_EN;
 267         ret = i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL,
 268                 data->control);
 269
 270         ret2 = iio_triggered_buffer_predisable(indio_dev);
 271         if (!ret)
 272                 ret = ret2;
 273
 274         return ret;
 275 }
 276
 277 static const struct iio_buffer_setup_ops tcs3414_buffer_setup_ops = {
 278         .postenable = tcs3414_buffer_postenable,
 279         .predisable = tcs3414_buffer_predisable,
 280 };
 281
 282 static int tcs3414_probe(struct i2c_client *client,
 283                            const struct i2c_device_id *id)
 284 {
 285         struct tcs3414_data *data;
 286         struct iio_dev *indio_dev;
 287         int ret;
 288
 289         indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
 290         if (indio_dev == NULL)
 291                 return -ENOMEM;
 292
 293         data = iio_priv(indio_dev);
 294         i2c_set_clientdata(client, indio_dev);
 295         data->client = client;
 296
 297         indio_dev->dev.parent = &client->dev;
 298         indio_dev->info = &tcs3414_info;
 299         indio_dev->name = TCS3414_DRV_NAME;
 300         indio_dev->channels = tcs3414_channels;
 301         indio_dev->num_channels = ARRAY_SIZE(tcs3414_channels);
 302         indio_dev->modes = INDIO_DIRECT_MODE;
 303
 304         ret = i2c_smbus_read_byte_data(data->client, TCS3414_ID);
 305         if (ret < 0)
 306                 return ret;
 307
 308         switch (ret & 0xf0) {
 309         case 0x00:
 310                 dev_info(&client->dev, "TCS3404 found\n");
 311                 break;
 312         case 0x10:
 313                 dev_info(&client->dev, "TCS3413/14/15/16 found\n");
 314                 break;
 315         default:
 316                 return -ENODEV;
 317         }
 318
 319         data->control = TCS3414_CONTROL_POWER;
 320         ret = i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL,
 321                 data->control);
 322         if (ret < 0)
 323                 return ret;
 324
 325         data->timing = TCS3414_INTEG_12MS; /* free running */
 326         ret = i2c_smbus_write_byte_data(data->client, TCS3414_TIMING,
 327                 data->timing);
 328         if (ret < 0)
 329                 return ret;
 330
 331         ret = i2c_smbus_read_byte_data(data->client, TCS3414_GAIN);
 332         if (ret < 0)
 333                 return ret;
 334         data->gain = ret;
 335
 336         ret = iio_triggered_buffer_setup(indio_dev, NULL,
 337                 tcs3414_trigger_handler, &tcs3414_buffer_setup_ops);
 338         if (ret < 0)
 339                 return ret;
 340
 341         ret = iio_device_register(indio_dev);
 342         if (ret < 0)
 343                 goto buffer_cleanup;
 344
 345         return 0;
 346
 347 buffer_cleanup:
 348         iio_triggered_buffer_cleanup(indio_dev);
 349         return ret;
 350 }
 351
 352 static int tcs3414_powerdown(struct tcs3414_data *data)
 353 {
 354         return i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL,
 355                 data->control & ~(TCS3414_CONTROL_POWER |
 356                 TCS3414_CONTROL_ADC_EN));
 357 }
 358
 359 static int tcs3414_remove(struct i2c_client *client)
 360 {
 361         struct iio_dev *indio_dev = i2c_get_clientdata(client);
 362
 363         iio_device_unregister(indio_dev);
 364         iio_triggered_buffer_cleanup(indio_dev);
 365         tcs3414_powerdown(iio_priv(indio_dev));
 366
 367         return 0;
 368 }
 369
 370 #ifdef CONFIG_PM_SLEEP
 371 static int tcs3414_suspend(struct device *dev)
 372 {
 373         struct tcs3414_data *data = iio_priv(i2c_get_clientdata(
 374                 to_i2c_client(dev)));
 375         return tcs3414_powerdown(data);
 376 }
 377
 378 static int tcs3414_resume(struct device *dev)
 379 {
 380         struct tcs3414_data *data = iio_priv(i2c_get_clientdata(
 381                 to_i2c_client(dev)));
 382         return i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL,
 383                 data->control);
 384 }
 385 #endif
 386
 387 static SIMPLE_DEV_PM_OPS(tcs3414_pm_ops, tcs3414_suspend, tcs3414_resume);
 388
 389 static const struct i2c_device_id tcs3414_id[] = {
 390         { "tcs3414", 0 },
 391         { }
 392 };
 393 MODULE_DEVICE_TABLE(i2c, tcs3414_id);
 394
 395 static struct i2c_driver tcs3414_driver = {
 396         .driver = {
 397                 .name   = TCS3414_DRV_NAME,
 398                 .pm     = &tcs3414_pm_ops,
 399         },
 400         .probe          = tcs3414_probe,
 401         .remove         = tcs3414_remove,
 402         .id_table       = tcs3414_id,
 403 };
 404 module_i2c_driver(tcs3414_driver);
 405
 406 MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
 407 MODULE_DESCRIPTION("TCS3414 digital color sensors driver");
 408 MODULE_LICENSE("GPL");