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 /* Ensure timestamp is naturally aligned */ 57 struct { 58 u16 chans[4]; 59 aligned_s64 timestamp; 60 } scan; 61 }; 62 63 #define TCS3414_CHANNEL(_color, _si, _addr) { \ 64 .type = IIO_INTENSITY, \ 65 .modified = 1, \ 66 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ 67 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \ 68 BIT(IIO_CHAN_INFO_INT_TIME), \ 69 .channel2 = IIO_MOD_LIGHT_##_color, \ 70 .address = _addr, \ 71 .scan_index = _si, \ 72 .scan_type = { \ 73 .sign = 'u', \ 74 .realbits = 16, \ 75 .storagebits = 16, \ 76 .endianness = IIO_CPU, \ 77 }, \ 78 } 79 80 /* scale factors: 1/gain */ 81 static const int tcs3414_scales[][2] = { 82 {1, 0}, {0, 250000}, {0, 62500}, {0, 15625} 83 }; 84 85 /* integration time in ms */ 86 static const int tcs3414_times[] = { 12, 100, 400 }; 87 88 static const struct iio_chan_spec tcs3414_channels[] = { 89 TCS3414_CHANNEL(GREEN, 0, TCS3414_DATA_GREEN), 90 TCS3414_CHANNEL(RED, 1, TCS3414_DATA_RED), 91 TCS3414_CHANNEL(BLUE, 2, TCS3414_DATA_BLUE), 92 TCS3414_CHANNEL(CLEAR, 3, TCS3414_DATA_CLEAR), 93 IIO_CHAN_SOFT_TIMESTAMP(4), 94 }; 95 96 static int tcs3414_req_data(struct tcs3414_data *data) 97 { 98 int tries = 25; 99 int ret; 100 101 ret = i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL, 102 data->control | TCS3414_CONTROL_ADC_EN); 103 if (ret < 0) 104 return ret; 105 106 while (tries--) { 107 ret = i2c_smbus_read_byte_data(data->client, TCS3414_CONTROL); 108 if (ret < 0) 109 return ret; 110 if (ret & TCS3414_CONTROL_ADC_VALID) 111 break; 112 msleep(20); 113 } 114 115 ret = i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL, 116 data->control); 117 if (ret < 0) 118 return ret; 119 120 if (tries < 0) { 121 dev_err(&data->client->dev, "data not ready\n"); 122 return -EIO; 123 } 124 125 return 0; 126 } 127 128 static int tcs3414_read_raw(struct iio_dev *indio_dev, 129 struct iio_chan_spec const *chan, 130 int *val, int *val2, long mask) 131 { 132 struct tcs3414_data *data = iio_priv(indio_dev); 133 int i, ret; 134 135 switch (mask) { 136 case IIO_CHAN_INFO_RAW: 137 if (!iio_device_claim_direct(indio_dev)) 138 return -EBUSY; 139 ret = tcs3414_req_data(data); 140 if (ret < 0) { 141 iio_device_release_direct(indio_dev); 142 return ret; 143 } 144 ret = i2c_smbus_read_word_data(data->client, chan->address); 145 iio_device_release_direct(indio_dev); 146 if (ret < 0) 147 return ret; 148 *val = ret; 149 return IIO_VAL_INT; 150 case IIO_CHAN_INFO_SCALE: 151 i = (data->gain & TCS3414_GAIN_MASK) >> TCS3414_GAIN_SHIFT; 152 *val = tcs3414_scales[i][0]; 153 *val2 = tcs3414_scales[i][1]; 154 return IIO_VAL_INT_PLUS_MICRO; 155 case IIO_CHAN_INFO_INT_TIME: 156 *val = 0; 157 *val2 = tcs3414_times[data->timing & TCS3414_INTEG_MASK] * 1000; 158 return IIO_VAL_INT_PLUS_MICRO; 159 } 160 return -EINVAL; 161 } 162 163 static int tcs3414_write_raw(struct iio_dev *indio_dev, 164 struct iio_chan_spec const *chan, 165 int val, int val2, long mask) 166 { 167 struct tcs3414_data *data = iio_priv(indio_dev); 168 int i; 169 170 switch (mask) { 171 case IIO_CHAN_INFO_SCALE: 172 for (i = 0; i < ARRAY_SIZE(tcs3414_scales); i++) { 173 if (val == tcs3414_scales[i][0] && 174 val2 == tcs3414_scales[i][1]) { 175 data->gain &= ~TCS3414_GAIN_MASK; 176 data->gain |= i << TCS3414_GAIN_SHIFT; 177 return i2c_smbus_write_byte_data( 178 data->client, TCS3414_GAIN, 179 data->gain); 180 } 181 } 182 return -EINVAL; 183 case IIO_CHAN_INFO_INT_TIME: 184 if (val != 0) 185 return -EINVAL; 186 for (i = 0; i < ARRAY_SIZE(tcs3414_times); i++) { 187 if (val2 == tcs3414_times[i] * 1000) { 188 data->timing &= ~TCS3414_INTEG_MASK; 189 data->timing |= i; 190 return i2c_smbus_write_byte_data( 191 data->client, TCS3414_TIMING, 192 data->timing); 193 } 194 } 195 return -EINVAL; 196 default: 197 return -EINVAL; 198 } 199 } 200 201 static irqreturn_t tcs3414_trigger_handler(int irq, void *p) 202 { 203 struct iio_poll_func *pf = p; 204 struct iio_dev *indio_dev = pf->indio_dev; 205 struct tcs3414_data *data = iio_priv(indio_dev); 206 int i, j = 0; 207 208 iio_for_each_active_channel(indio_dev, i) { 209 int ret = i2c_smbus_read_word_data(data->client, 210 TCS3414_DATA_GREEN + 2*i); 211 if (ret < 0) 212 goto done; 213 214 data->scan.chans[j++] = ret; 215 } 216 217 iio_push_to_buffers_with_timestamp(indio_dev, &data->scan, 218 iio_get_time_ns(indio_dev)); 219 220 done: 221 iio_trigger_notify_done(indio_dev->trig); 222 223 return IRQ_HANDLED; 224 } 225 226 static IIO_CONST_ATTR(scale_available, "1 0.25 0.0625 0.015625"); 227 static IIO_CONST_ATTR_INT_TIME_AVAIL("0.012 0.1 0.4"); 228 229 static struct attribute *tcs3414_attributes[] = { 230 &iio_const_attr_scale_available.dev_attr.attr, 231 &iio_const_attr_integration_time_available.dev_attr.attr, 232 NULL 233 }; 234 235 static const struct attribute_group tcs3414_attribute_group = { 236 .attrs = tcs3414_attributes, 237 }; 238 239 static const struct iio_info tcs3414_info = { 240 .read_raw = tcs3414_read_raw, 241 .write_raw = tcs3414_write_raw, 242 .attrs = &tcs3414_attribute_group, 243 }; 244 245 static int tcs3414_buffer_postenable(struct iio_dev *indio_dev) 246 { 247 struct tcs3414_data *data = iio_priv(indio_dev); 248 249 data->control |= TCS3414_CONTROL_ADC_EN; 250 return i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL, 251 data->control); 252 } 253 254 static int tcs3414_buffer_predisable(struct iio_dev *indio_dev) 255 { 256 struct tcs3414_data *data = iio_priv(indio_dev); 257 258 data->control &= ~TCS3414_CONTROL_ADC_EN; 259 return i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL, 260 data->control); 261 } 262 263 static const struct iio_buffer_setup_ops tcs3414_buffer_setup_ops = { 264 .postenable = tcs3414_buffer_postenable, 265 .predisable = tcs3414_buffer_predisable, 266 }; 267 268 static int tcs3414_powerdown(struct tcs3414_data *data) 269 { 270 return i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL, 271 data->control & ~(TCS3414_CONTROL_POWER | 272 TCS3414_CONTROL_ADC_EN)); 273 } 274 275 static void tcs3414_powerdown_cleanup(void *data) 276 { 277 tcs3414_powerdown(data); 278 } 279 280 static int tcs3414_probe(struct i2c_client *client) 281 { 282 struct tcs3414_data *data; 283 struct iio_dev *indio_dev; 284 int ret; 285 286 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data)); 287 if (indio_dev == NULL) 288 return -ENOMEM; 289 290 data = iio_priv(indio_dev); 291 i2c_set_clientdata(client, indio_dev); 292 data->client = client; 293 294 indio_dev->info = &tcs3414_info; 295 indio_dev->name = TCS3414_DRV_NAME; 296 indio_dev->channels = tcs3414_channels; 297 indio_dev->num_channels = ARRAY_SIZE(tcs3414_channels); 298 indio_dev->modes = INDIO_DIRECT_MODE; 299 300 ret = i2c_smbus_read_byte_data(data->client, TCS3414_ID); 301 if (ret < 0) 302 return ret; 303 304 switch (ret & 0xf0) { 305 case 0x00: 306 dev_info(&client->dev, "TCS3404 found\n"); 307 break; 308 case 0x10: 309 dev_info(&client->dev, "TCS3413/14/15/16 found\n"); 310 break; 311 default: 312 return -ENODEV; 313 } 314 315 data->control = TCS3414_CONTROL_POWER; 316 ret = i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL, 317 data->control); 318 if (ret < 0) 319 return ret; 320 321 ret = devm_add_action_or_reset(&client->dev, tcs3414_powerdown_cleanup, 322 data); 323 if (ret < 0) 324 return ret; 325 326 data->timing = TCS3414_INTEG_12MS; /* free running */ 327 ret = i2c_smbus_write_byte_data(data->client, TCS3414_TIMING, 328 data->timing); 329 if (ret < 0) 330 return ret; 331 332 ret = i2c_smbus_read_byte_data(data->client, TCS3414_GAIN); 333 if (ret < 0) 334 return ret; 335 data->gain = ret; 336 337 ret = devm_iio_triggered_buffer_setup(&client->dev, indio_dev, NULL, 338 tcs3414_trigger_handler, &tcs3414_buffer_setup_ops); 339 if (ret < 0) 340 return ret; 341 342 return devm_iio_device_register(&client->dev, indio_dev); 343 } 344 345 static int tcs3414_suspend(struct device *dev) 346 { 347 struct tcs3414_data *data = iio_priv(i2c_get_clientdata( 348 to_i2c_client(dev))); 349 return tcs3414_powerdown(data); 350 } 351 352 static int tcs3414_resume(struct device *dev) 353 { 354 struct tcs3414_data *data = iio_priv(i2c_get_clientdata( 355 to_i2c_client(dev))); 356 return i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL, 357 data->control); 358 } 359 360 static DEFINE_SIMPLE_DEV_PM_OPS(tcs3414_pm_ops, tcs3414_suspend, 361 tcs3414_resume); 362 363 static const struct i2c_device_id tcs3414_id[] = { 364 { "tcs3414" }, 365 { } 366 }; 367 MODULE_DEVICE_TABLE(i2c, tcs3414_id); 368 369 static struct i2c_driver tcs3414_driver = { 370 .driver = { 371 .name = TCS3414_DRV_NAME, 372 .pm = pm_sleep_ptr(&tcs3414_pm_ops), 373 }, 374 .probe = tcs3414_probe, 375 .id_table = tcs3414_id, 376 }; 377 module_i2c_driver(tcs3414_driver); 378 379 MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>"); 380 MODULE_DESCRIPTION("TCS3414 digital color sensors driver"); 381 MODULE_LICENSE("GPL"); 382