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 s64 timestamp __aligned(8); 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 ret = iio_device_claim_direct_mode(indio_dev); 138 if (ret) 139 return ret; 140 ret = tcs3414_req_data(data); 141 if (ret < 0) { 142 iio_device_release_direct_mode(indio_dev); 143 return ret; 144 } 145 ret = i2c_smbus_read_word_data(data->client, chan->address); 146 iio_device_release_direct_mode(indio_dev); 147 if (ret < 0) 148 return ret; 149 *val = ret; 150 return IIO_VAL_INT; 151 case IIO_CHAN_INFO_SCALE: 152 i = (data->gain & TCS3414_GAIN_MASK) >> TCS3414_GAIN_SHIFT; 153 *val = tcs3414_scales[i][0]; 154 *val2 = tcs3414_scales[i][1]; 155 return IIO_VAL_INT_PLUS_MICRO; 156 case IIO_CHAN_INFO_INT_TIME: 157 *val = 0; 158 *val2 = tcs3414_times[data->timing & TCS3414_INTEG_MASK] * 1000; 159 return IIO_VAL_INT_PLUS_MICRO; 160 } 161 return -EINVAL; 162 } 163 164 static int tcs3414_write_raw(struct iio_dev *indio_dev, 165 struct iio_chan_spec const *chan, 166 int val, int val2, long mask) 167 { 168 struct tcs3414_data *data = iio_priv(indio_dev); 169 int i; 170 171 switch (mask) { 172 case IIO_CHAN_INFO_SCALE: 173 for (i = 0; i < ARRAY_SIZE(tcs3414_scales); i++) { 174 if (val == tcs3414_scales[i][0] && 175 val2 == tcs3414_scales[i][1]) { 176 data->gain &= ~TCS3414_GAIN_MASK; 177 data->gain |= i << TCS3414_GAIN_SHIFT; 178 return i2c_smbus_write_byte_data( 179 data->client, TCS3414_GAIN, 180 data->gain); 181 } 182 } 183 return -EINVAL; 184 case IIO_CHAN_INFO_INT_TIME: 185 if (val != 0) 186 return -EINVAL; 187 for (i = 0; i < ARRAY_SIZE(tcs3414_times); i++) { 188 if (val2 == tcs3414_times[i] * 1000) { 189 data->timing &= ~TCS3414_INTEG_MASK; 190 data->timing |= i; 191 return i2c_smbus_write_byte_data( 192 data->client, TCS3414_TIMING, 193 data->timing); 194 } 195 } 196 return -EINVAL; 197 default: 198 return -EINVAL; 199 } 200 } 201 202 static irqreturn_t tcs3414_trigger_handler(int irq, void *p) 203 { 204 struct iio_poll_func *pf = p; 205 struct iio_dev *indio_dev = pf->indio_dev; 206 struct tcs3414_data *data = iio_priv(indio_dev); 207 int i, j = 0; 208 209 iio_for_each_active_channel(indio_dev, i) { 210 int ret = i2c_smbus_read_word_data(data->client, 211 TCS3414_DATA_GREEN + 2*i); 212 if (ret < 0) 213 goto done; 214 215 data->scan.chans[j++] = ret; 216 } 217 218 iio_push_to_buffers_with_timestamp(indio_dev, &data->scan, 219 iio_get_time_ns(indio_dev)); 220 221 done: 222 iio_trigger_notify_done(indio_dev->trig); 223 224 return IRQ_HANDLED; 225 } 226 227 static IIO_CONST_ATTR(scale_available, "1 0.25 0.0625 0.015625"); 228 static IIO_CONST_ATTR_INT_TIME_AVAIL("0.012 0.1 0.4"); 229 230 static struct attribute *tcs3414_attributes[] = { 231 &iio_const_attr_scale_available.dev_attr.attr, 232 &iio_const_attr_integration_time_available.dev_attr.attr, 233 NULL 234 }; 235 236 static const struct attribute_group tcs3414_attribute_group = { 237 .attrs = tcs3414_attributes, 238 }; 239 240 static const struct iio_info tcs3414_info = { 241 .read_raw = tcs3414_read_raw, 242 .write_raw = tcs3414_write_raw, 243 .attrs = &tcs3414_attribute_group, 244 }; 245 246 static int tcs3414_buffer_postenable(struct iio_dev *indio_dev) 247 { 248 struct tcs3414_data *data = iio_priv(indio_dev); 249 250 data->control |= TCS3414_CONTROL_ADC_EN; 251 return i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL, 252 data->control); 253 } 254 255 static int tcs3414_buffer_predisable(struct iio_dev *indio_dev) 256 { 257 struct tcs3414_data *data = iio_priv(indio_dev); 258 259 data->control &= ~TCS3414_CONTROL_ADC_EN; 260 return i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL, 261 data->control); 262 } 263 264 static const struct iio_buffer_setup_ops tcs3414_buffer_setup_ops = { 265 .postenable = tcs3414_buffer_postenable, 266 .predisable = tcs3414_buffer_predisable, 267 }; 268 269 static int tcs3414_powerdown(struct tcs3414_data *data) 270 { 271 return i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL, 272 data->control & ~(TCS3414_CONTROL_POWER | 273 TCS3414_CONTROL_ADC_EN)); 274 } 275 276 static void tcs3414_powerdown_cleanup(void *data) 277 { 278 tcs3414_powerdown(data); 279 } 280 281 static int tcs3414_probe(struct i2c_client *client) 282 { 283 struct tcs3414_data *data; 284 struct iio_dev *indio_dev; 285 int ret; 286 287 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data)); 288 if (indio_dev == NULL) 289 return -ENOMEM; 290 291 data = iio_priv(indio_dev); 292 i2c_set_clientdata(client, indio_dev); 293 data->client = client; 294 295 indio_dev->info = &tcs3414_info; 296 indio_dev->name = TCS3414_DRV_NAME; 297 indio_dev->channels = tcs3414_channels; 298 indio_dev->num_channels = ARRAY_SIZE(tcs3414_channels); 299 indio_dev->modes = INDIO_DIRECT_MODE; 300 301 ret = i2c_smbus_read_byte_data(data->client, TCS3414_ID); 302 if (ret < 0) 303 return ret; 304 305 switch (ret & 0xf0) { 306 case 0x00: 307 dev_info(&client->dev, "TCS3404 found\n"); 308 break; 309 case 0x10: 310 dev_info(&client->dev, "TCS3413/14/15/16 found\n"); 311 break; 312 default: 313 return -ENODEV; 314 } 315 316 data->control = TCS3414_CONTROL_POWER; 317 ret = i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL, 318 data->control); 319 if (ret < 0) 320 return ret; 321 322 ret = devm_add_action_or_reset(&client->dev, tcs3414_powerdown_cleanup, 323 data); 324 if (ret < 0) 325 return ret; 326 327 data->timing = TCS3414_INTEG_12MS; /* free running */ 328 ret = i2c_smbus_write_byte_data(data->client, TCS3414_TIMING, 329 data->timing); 330 if (ret < 0) 331 return ret; 332 333 ret = i2c_smbus_read_byte_data(data->client, TCS3414_GAIN); 334 if (ret < 0) 335 return ret; 336 data->gain = ret; 337 338 ret = devm_iio_triggered_buffer_setup(&client->dev, indio_dev, NULL, 339 tcs3414_trigger_handler, &tcs3414_buffer_setup_ops); 340 if (ret < 0) 341 return ret; 342 343 return devm_iio_device_register(&client->dev, indio_dev); 344 } 345 346 static int tcs3414_suspend(struct device *dev) 347 { 348 struct tcs3414_data *data = iio_priv(i2c_get_clientdata( 349 to_i2c_client(dev))); 350 return tcs3414_powerdown(data); 351 } 352 353 static int tcs3414_resume(struct device *dev) 354 { 355 struct tcs3414_data *data = iio_priv(i2c_get_clientdata( 356 to_i2c_client(dev))); 357 return i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL, 358 data->control); 359 } 360 361 static DEFINE_SIMPLE_DEV_PM_OPS(tcs3414_pm_ops, tcs3414_suspend, 362 tcs3414_resume); 363 364 static const struct i2c_device_id tcs3414_id[] = { 365 { "tcs3414" }, 366 { } 367 }; 368 MODULE_DEVICE_TABLE(i2c, tcs3414_id); 369 370 static struct i2c_driver tcs3414_driver = { 371 .driver = { 372 .name = TCS3414_DRV_NAME, 373 .pm = pm_sleep_ptr(&tcs3414_pm_ops), 374 }, 375 .probe = tcs3414_probe, 376 .id_table = tcs3414_id, 377 }; 378 module_i2c_driver(tcs3414_driver); 379 380 MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>"); 381 MODULE_DESCRIPTION("TCS3414 digital color sensors driver"); 382 MODULE_LICENSE("GPL"); 383