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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 | /* sensor.h - public sensor driver API */ /* * Copyright (c) 2016 Intel Corporation * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #ifndef __SENSOR_H__ #define __SENSOR_H__ /** * @brief Sensor Interface * @defgroup sensor_interface Sensor Interface * @ingroup io_interfaces * @{ */ #ifdef __cplusplus extern "C" { #endif #include <stdint.h> #include <device.h> #include <errno.h> /** @brief Sensor value types. */ enum sensor_value_type { /** val1 contains an integer value, val2 is unused. */ SENSOR_TYPE_INT, /** * val1 contains an integer value, val2 is the fractional value. * To obtain the final value, use the formula: val1 + val2 * * 10^(-6). */ SENSOR_TYPE_INT_PLUS_MICRO, /** * @brief val1 contains a Q16.16 representation, val2 is * unused. */ SENSOR_TYPE_Q16_16, /** @brief dval contains a floating point value. */ SENSOR_TYPE_DOUBLE, }; /** * @brief Representation of a sensor readout value. * * The meaning of the fields is dictated by the type field. */ struct sensor_value { enum sensor_value_type type; union { struct { int32_t val1; int32_t val2; }; double dval; }; }; /** * @brief Sensor channels. */ enum sensor_channel { /** Acceleration on the X axis, in m/s^2. */ SENSOR_CHAN_ACCEL_X, /** Acceleration on the Y axis, in m/s^2. */ SENSOR_CHAN_ACCEL_Y, /** Acceleration on the Z axis, in m/s^2. */ SENSOR_CHAN_ACCEL_Z, /** Acceleration on any axis. */ SENSOR_CHAN_ACCEL_ANY, /** Angular velocity around the X axis, in radians/s. */ SENSOR_CHAN_GYRO_X, /** Angular velocity around the Y axis, in radians/s. */ SENSOR_CHAN_GYRO_Y, /** Angular velocity around the Z axis, in radians/s. */ SENSOR_CHAN_GYRO_Z, /** Angular velocity on any axis. */ SENSOR_CHAN_GYRO_ANY, /** Magnetic field on the X axis, in Gauss. */ SENSOR_CHAN_MAGN_X, /** Magnetic field on the Y axis, in Gauss. */ SENSOR_CHAN_MAGN_Y, /** Magnetic field on the Z axis, in Gauss. */ SENSOR_CHAN_MAGN_Z, /** Magnetic field on any axis. */ SENSOR_CHAN_MAGN_ANY, /** Temperature in degrees Celsius. */ SENSOR_CHAN_TEMP, /** Pressure in kilopascal. */ SENSOR_CHAN_PRESS, /** * Proximity. Adimensional. A value of 1 indicates that an * object is close. */ SENSOR_CHAN_PROX, /** Humidity, in milli percent. */ SENSOR_CHAN_HUMIDITY, /** Illuminance in visible spectrum, in lux. */ SENSOR_CHAN_LIGHT, /** Illuminance in infra-red spectrum, in lux. */ SENSOR_CHAN_IR, }; /** * @brief Sensor trigger types. */ enum sensor_trigger_type { /** * Timer-based trigger, useful when the sensor does not have an * interrupt line. */ SENSOR_TRIG_TIMER, /** Trigger fires whenever new data is ready. */ SENSOR_TRIG_DATA_READY, /** * Trigger fires when the selected channel varies significantly. * This includes any-motion detection when the channel is * acceleration or gyro. If detection is based on slope between * successive channel readings, the slope threshold is configured * via the @ref SENSOR_ATTR_SLOPE_TH and @ref SENSOR_ATTR_SLOPE_DUR * attributes. */ SENSOR_TRIG_DELTA, /** Trigger fires when a near/far event is detected. */ SENSOR_TRIG_NEAR_FAR, /** * Trigger fires when channel reading transitions configured * thresholds. The thresholds are configured via the @ref * SENSOR_ATTR_LOWER_THRESH and @ref SENSOR_ATTR_UPPER_THRESH * attributes. */ SENSOR_TRIG_THRESHOLD, }; /** * @brief Sensor trigger spec. */ struct sensor_trigger { /** Trigger type. */ enum sensor_trigger_type type; /** Channel the trigger is set on. */ enum sensor_channel chan; }; /** * @brief Sensor attribute types. */ enum sensor_attribute { /** * Sensor sampling frequency, i.e. how many times a second the * sensor takes a measurement. */ SENSOR_ATTR_SAMPLING_FREQUENCY, /** Lower threshold for trigger. */ SENSOR_ATTR_LOWER_THRESH, /** Upper threshold for trigger. */ SENSOR_ATTR_UPPER_THRESH, /** Threshold for any-motion (slope) trigger. */ SENSOR_ATTR_SLOPE_TH, /** * Duration for which the slope values needs to be * outside the threshold for the trigger to fire. */ SENSOR_ATTR_SLOPE_DUR, /** Oversampling factor */ SENSOR_ATTR_OVERSAMPLING, /** Sensor range, in SI units. */ SENSOR_ATTR_FULL_SCALE, /** * The sensor value returned will be altered by the amount indicated by * offset: final_value = sensor_value + offset. */ SENSOR_ATTR_OFFSET, /** * Calibration target. This will be used by the internal chip's * algorithms to calibrate itself on a certain axis, or all of them. */ SENSOR_ATTR_CALIB_TARGET, }; typedef void (*sensor_trigger_handler_t)(struct device *dev, struct sensor_trigger *trigger); typedef int (*sensor_attr_set_t)(struct device *dev, enum sensor_channel chan, enum sensor_attribute attr, const struct sensor_value *val); typedef int (*sensor_trigger_set_t)(struct device *dev, const struct sensor_trigger *trig, sensor_trigger_handler_t handler); typedef int (*sensor_sample_fetch_t)(struct device *dev); typedef int (*sensor_channel_get_t)(struct device *dev, enum sensor_channel chan, struct sensor_value *val); struct sensor_driver_api { sensor_attr_set_t attr_set; sensor_trigger_set_t trigger_set; sensor_sample_fetch_t sample_fetch; sensor_channel_get_t channel_get; }; /** * @brief Set an attribute for a sensor * * @param dev Pointer to the sensor device * @param chan The channel the attribute belongs to, if any. Some * attributes may only be set for all channels of a device, depending on * device capabilities. * @param attr The attribute to set * @param val The value to set the attribute to * * @return 0 if successful, negative errno code if failure. */ static inline int sensor_attr_set(struct device *dev, enum sensor_channel chan, enum sensor_attribute attr, const struct sensor_value *val) { struct sensor_driver_api *api; api = (struct sensor_driver_api *)dev->driver_api; if (!api->attr_set) { return -ENOTSUP; } return api->attr_set(dev, chan, attr, val); } /** * @brief Activate a sensor's trigger and set the trigger handler * * The handler will be called from a fiber, so I2C or SPI operations are * safe. However, the fiber's stack is limited and defined by the * driver. It is currently up to the caller to ensure that the handler * does not overflow the stack. * * @param dev Pointer to the sensor device * @param trig The trigger to activate * @param handler The function that should be called when the trigger * fires * * @return 0 if successful, negative errno code if failure. */ static inline int sensor_trigger_set(struct device *dev, struct sensor_trigger *trig, sensor_trigger_handler_t handler) { struct sensor_driver_api *api; api = (struct sensor_driver_api *)dev->driver_api; if (!api->trigger_set) { return -ENOTSUP; } return api->trigger_set(dev, trig, handler); } /** * @brief Fetch a sample from the sensor and store it in an internal * driver buffer * * Read all of a sensor's active channels and, if necessary, perform any * additional operations necessary to make the values useful. The user * may then get individual channel values by calling @ref * sensor_channel_get. * * Since the function communicates with the sensor device, it is unsafe * to call it in an ISR if the device is connected via I2C or SPI. * * @param dev Pointer to the sensor device * * @return 0 if successful, negative errno code if failure. */ static inline int sensor_sample_fetch(struct device *dev) { struct sensor_driver_api *api; api = (struct sensor_driver_api *)dev->driver_api; return api->sample_fetch(dev); } /** * @brief Get a reading from a sensor device * * Return a useful value for a particular channel, from the driver's * internal data. Before calling this function, a sample must be * obtained by calling @ref sensor_sample_fetch. It is guaranteed that * two subsequent calls of this function for the same channels will * yield the same value, if @ref sensor_sample_fetch has not been called * in the meantime. * * @param dev Pointer to the sensor device * @param chan The channel to read * @param val Where to store the value * * @return 0 if successful, negative errno code if failure. */ static inline int sensor_channel_get(struct device *dev, enum sensor_channel chan, struct sensor_value *val) { struct sensor_driver_api *api; api = (struct sensor_driver_api *)dev->driver_api; return api->channel_get(dev, chan, val); } #ifdef CONFIG_SENSOR_DELAYED_WORK typedef void (*sensor_work_handler_t)(void *arg); /** * @brief Sensor delayed work descriptor. * * Used by sensor drivers internally to delay function calls to a fiber * context. */ struct sensor_work { sensor_work_handler_t handler; void *arg; }; /** * @brief Get a fifo to which sensor delayed work can be submitted * * If @ref CONFIG_SENSOR_DELAYED_WORK is enabled, the system creates a * global fiber that can execute delayed work on behalf of drivers. * This is useful for drivers which need a mechanism of delayed work but * do not create their own fibers due to system resource constraints. */ struct nano_fifo *sensor_get_work_fifo(void); #endif /** * @brief The value of gravitational constant in micro m/s^2. */ #define SENSOR_G 9806650LL /** * @brief The value of constant PI in micros. */ #define SENSOR_PI 3141592LL /** * @brief Helper function to convert acceleration from m/s^2 to Gs * * @param ms2 A pointer to a sensor_value struct holding the acceleration, * in m/s^2. * * @return The converted value, in Gs. */ static inline int32_t sensor_ms2_to_g(const struct sensor_value *ms2) { int64_t micro_ms2 = ms2->val1 * 1000000LL + ms2->val2; if (micro_ms2 > 0) { return (micro_ms2 + SENSOR_G / 2) / SENSOR_G; } else { return (micro_ms2 - SENSOR_G / 2) / SENSOR_G; } } /** * @brief Helper function to convert acceleration from Gs to m/s^2 * * @param g The G value to be converted. * @param ms2 A pointer to a sensor_value struct, where the result is stored. */ static inline void sensor_g_to_ms2(int32_t g, struct sensor_value *ms2) { ms2->type = SENSOR_TYPE_INT_PLUS_MICRO; ms2->val1 = ((int64_t)g * SENSOR_G) / 1000000LL; ms2->val2 = ((int64_t)g * SENSOR_G) % 1000000LL; } /** * @brief Helper function for converting radians to degrees. * * @param rad A pointer to a sensor_value struct, holding the value in radians. * * @return The converted value, in degrees. */ static inline int32_t sensor_rad_to_degrees(const struct sensor_value *rad) { int64_t micro_rad_s = rad->val1 * 1000000LL + rad->val2; if (micro_rad_s > 0) { return (micro_rad_s * 180LL + SENSOR_PI / 2) / SENSOR_PI; } else { return (micro_rad_s * 180LL - SENSOR_PI / 2) / SENSOR_PI; } } /** * @brief Helper function for converting degrees to radians. * * @param d The value (in degrees) to be converted. * @param rad A pointer to a sensor_value struct, where the result is stored. */ static inline void sensor_degrees_to_rad(int32_t d, struct sensor_value *rad) { rad->type = SENSOR_TYPE_INT_PLUS_MICRO; rad->val1 = ((int64_t)d * SENSOR_PI / 180LL) / 1000000LL; rad->val2 = ((int64_t)d * SENSOR_PI / 180LL) % 1000000LL; } #ifdef __cplusplus } #endif /** * @} */ #endif /* __SENSOR_H__ */ |