2 * Copyright (C) 2014 Intel Corporation.
8 #include <cutils/properties.h>
9 #include <hardware/sensors.h>
11 #include "enumeration.h"
12 #include "description.h"
15 #define IIO_SENSOR_HAL_VERSION 1
20 * We acquire a number of parameters about sensors by reading properties.
21 * The idea here is that someone (either a script, or daemon, sets them
22 * depending on the set of sensors present on the machine.
24 * There are fallback paths in case the properties are not defined, but it is
25 * highly desirable to at least have the following for each sensor:
27 * ro.iio.anglvel.name = Gyroscope
28 * ro.iio.anglvel.vendor = Intel
29 * ro.iio.anglvel.max_range = 35
30 * ro.iio.anglvel.resolution = 0.002
31 * ro.iio.anglvel.power = 6.1
33 * Besides these, we have a couple of knobs initially used to cope with Intel
34 * Sensor Hub oddities, such as HID inspired units or firmware bugs:
36 * ro.iio.anglvel.transform = ISH
37 * ro.iio.anglvel.quirks = init-rate
39 * The "terse" quirk indicates that the underlying driver only sends events
40 * when the sensor reports a change. The HAL then periodically generates
41 * duplicate events so the sensor behaves as a continously firing one.
43 * The "noisy" quirk indicates that the underlying driver has a unusually high
44 * level of noise in its readings, and that the HAL has to accomodate it
45 * somehow, e.g. in the magnetometer calibration code path.
47 * This one is used specifically to pass a calibration scale to ALS drivers:
49 * ro.iio.illuminance.name = CPLM3218x Ambient Light Sensor
50 * ro.iio.illuminance.vendor = Capella Microsystems
51 * ro.iio.illuminance.max_range = 167000
52 * ro.iio.illuminance.resolution = 1
53 * ro.iio.illuminance.power = .001
54 * ro.iio.illuminance.illumincalib = 7400
56 * There's a 'opt_scale' specifier, documented as follows:
58 * This adds support for a scaling factor that can be expressed
59 * using properties, for all sensors, on a channel basis. That
60 * scaling factor is applied after all other transforms have been
61 * applied, and is intended as a way to compensate for problems
62 * such as an incorrect axis polarity for a given sensor.
64 * The syntax is <usual property prefix>.<channel>.opt_scale, e.g.
65 * ro.iio.accel.y.opt_scale = -1 to negate the sign of the y readings
66 * for the accelerometer.
68 * For sensors using a single channel - and only those - the channel
69 * name is implicitly void and a syntax such as ro.iio.illuminance.
70 * opt_scale = 3 has to be used.
72 * 'panel' and 'rotation' specifiers can be used to express ACPI PLD placement
73 * information ; if found they will be used in priority over the actual ACPI
74 * data. That is intended as a way to verify values during development.
76 * It's possible to use the contents of the iio device name as a way to
77 * discriminate between sensors. Several sensors of the same type can coexist:
78 * e.g. ro.iio.temp.bmg160.name = BMG160 Thermometer will be used in priority
79 * over ro.iio.temp.name = BMC150 Thermometer if the sensor for which we query
80 * properties values happen to have its iio device name set to bmg160.
83 static int sensor_get_st_prop (int s, const char* sel, char val[MAX_NAME_SIZE])
85 char prop_name[PROP_NAME_MAX];
86 char prop_val[PROP_VALUE_MAX];
87 char extended_sel[PROP_VALUE_MAX];
89 int i = sensor_info[s].catalog_index;
90 const char *prefix = sensor_catalog[i].tag;
92 /* First try most specialized form, like ro.iio.anglvel.bmg160.name */
94 snprintf(extended_sel, PROP_NAME_MAX, "%s.%s",
95 sensor_info[s].internal_name, sel);
97 snprintf(prop_name, PROP_NAME_MAX, PROP_BASE, prefix, extended_sel);
99 if (property_get(prop_name, prop_val, "")) {
100 strncpy(val, prop_val, MAX_NAME_SIZE-1);
101 val[MAX_NAME_SIZE-1] = '\0';
105 /* Fall back to simple form, like ro.iio.anglvel.name */
107 sprintf(prop_name, PROP_BASE, prefix, sel);
109 if (property_get(prop_name, prop_val, "")) {
110 strncpy(val, prop_val, MAX_NAME_SIZE-1);
111 val[MAX_NAME_SIZE-1] = '\0';
119 int sensor_get_prop (int s, const char* sel, int* val)
121 char buf[MAX_NAME_SIZE];
123 if (sensor_get_st_prop(s, sel, buf))
131 int sensor_get_fl_prop (int s, const char* sel, float* val)
133 char buf[MAX_NAME_SIZE];
135 if (sensor_get_st_prop(s, sel, buf))
138 *val = (float) strtod(buf, NULL);
143 char* sensor_get_name (int s)
145 if (sensor_info[s].friendly_name[0] != '\0' ||
146 !sensor_get_st_prop(s, "name", sensor_info[s].friendly_name))
147 return sensor_info[s].friendly_name;
149 /* If we got a iio device name from sysfs, use it */
150 if (sensor_info[s].internal_name[0]) {
151 snprintf(sensor_info[s].friendly_name, MAX_NAME_SIZE, "S%d-%s",
152 s, sensor_info[s].internal_name);
154 sprintf(sensor_info[s].friendly_name, "S%d", s);
157 return sensor_info[s].friendly_name;
161 char* sensor_get_vendor (int s)
163 if (sensor_info[s].vendor_name[0] ||
164 !sensor_get_st_prop(s, "vendor", sensor_info[s].vendor_name))
165 return sensor_info[s].vendor_name;
171 int sensor_get_version (__attribute__((unused)) int s)
173 return IIO_SENSOR_HAL_VERSION;
177 float sensor_get_max_range (int s)
179 if (sensor_info[s].max_range != 0.0 ||
180 !sensor_get_fl_prop(s, "max_range", &sensor_info[s].max_range))
181 return sensor_info[s].max_range;
183 /* Try returning a sensible value given the sensor type */
185 /* We should cap returned samples accordingly... */
187 switch (sensor_info[s].type) {
188 case SENSOR_TYPE_ACCELEROMETER: /* m/s^2 */
191 case SENSOR_TYPE_MAGNETIC_FIELD: /* micro-tesla */
194 case SENSOR_TYPE_ORIENTATION: /* degrees */
197 case SENSOR_TYPE_GYROSCOPE: /* radians/s */
200 case SENSOR_TYPE_LIGHT: /* SI lux units */
203 case SENSOR_TYPE_AMBIENT_TEMPERATURE: /* °C */
204 case SENSOR_TYPE_TEMPERATURE: /* °C */
205 case SENSOR_TYPE_PROXIMITY: /* centimeters */
206 case SENSOR_TYPE_PRESSURE: /* hecto-pascal */
207 case SENSOR_TYPE_RELATIVE_HUMIDITY: /* percent */
215 static float sensor_get_min_freq (int s)
218 * Check if a low cap has been specified for this sensor sampling rate.
219 * In some case, even when the driver supports lower rate, we still
220 * wish to receive a certain number of samples per seconds for various
221 * reasons (calibration, filtering, no change in power consumption...).
226 if (!sensor_get_fl_prop(s, "min_freq", &min_freq))
233 static float sensor_get_max_freq (int s)
237 if (!sensor_get_fl_prop(s, "max_freq", &max_freq))
243 int sensor_get_cal_steps (int s)
246 if (!sensor_get_prop(s, "cal_steps", &cal_steps))
252 float sensor_get_resolution (int s)
254 if (sensor_info[s].resolution != 0.0 ||
255 !sensor_get_fl_prop(s, "resolution", &sensor_info[s].resolution))
256 return sensor_info[s].resolution;
262 float sensor_get_power (int s)
264 /* mA used while sensor is in use ; not sure about volts :) */
265 if (sensor_info[s].power != 0.0 ||
266 !sensor_get_fl_prop(s, "power", &sensor_info[s].power))
267 return sensor_info[s].power;
273 float sensor_get_illumincalib (int s)
275 /* calibrating the ALS Sensor*/
276 if (sensor_info[s].illumincalib != 0.0 ||
277 !sensor_get_fl_prop(s, "illumincalib", &sensor_info[s].illumincalib)) {
278 return sensor_info[s].illumincalib;
285 uint32_t sensor_get_quirks (int s)
287 char quirks_buf[MAX_NAME_SIZE];
289 /* Read and decode quirks property on first reference */
290 if (!(sensor_info[s].quirks & QUIRK_ALREADY_DECODED)) {
291 quirks_buf[0] = '\0';
292 sensor_get_st_prop(s, "quirks", quirks_buf);
294 if (strstr(quirks_buf, "init-rate"))
295 sensor_info[s].quirks |= QUIRK_INITIAL_RATE;
297 if (strstr(quirks_buf, "continuous"))
298 sensor_info[s].quirks |= QUIRK_FORCE_CONTINUOUS;
300 if (strstr(quirks_buf, "terse"))
301 sensor_info[s].quirks |= QUIRK_TERSE_DRIVER;
303 if (strstr(quirks_buf, "noisy"))
304 sensor_info[s].quirks |= QUIRK_NOISY;
306 sensor_info[s].quirks |= QUIRK_ALREADY_DECODED;
309 return sensor_info[s].quirks;
313 int sensor_get_order (int s, unsigned char map[MAX_CHANNELS])
315 char buf[MAX_NAME_SIZE];
317 int count = sensor_catalog[sensor_info[s].catalog_index].num_channels;
319 if (sensor_get_st_prop(s, "order", buf))
320 return 0; /* No order property */
322 /* Assume ASCII characters, in the '0'..'9' range */
324 for (i=0; i<count; i++)
325 if (buf[i] - '0' >= count) {
326 ALOGE("Order index out of range for sensor %d\n", s);
330 for (i=0; i<count; i++)
331 map[i] = buf[i] - '0';
333 return 1; /* OK to use modified ordering map */
336 char* sensor_get_string_type (int s)
338 switch (sensor_info[s].type) {
339 case SENSOR_TYPE_ACCELEROMETER:
340 return SENSOR_STRING_TYPE_ACCELEROMETER;
342 case SENSOR_TYPE_MAGNETIC_FIELD:
343 return SENSOR_STRING_TYPE_MAGNETIC_FIELD;
345 case SENSOR_TYPE_ORIENTATION:
346 return SENSOR_STRING_TYPE_ORIENTATION;
348 case SENSOR_TYPE_GYROSCOPE:
349 return SENSOR_STRING_TYPE_GYROSCOPE;
351 case SENSOR_TYPE_GYROSCOPE_UNCALIBRATED:
352 return SENSOR_STRING_TYPE_GYROSCOPE_UNCALIBRATED;
354 case SENSOR_TYPE_LIGHT:
355 return SENSOR_STRING_TYPE_LIGHT;
357 case SENSOR_TYPE_AMBIENT_TEMPERATURE:
358 return SENSOR_STRING_TYPE_AMBIENT_TEMPERATURE;
360 case SENSOR_TYPE_TEMPERATURE:
361 return SENSOR_STRING_TYPE_TEMPERATURE;
363 case SENSOR_TYPE_PROXIMITY:
364 return SENSOR_STRING_TYPE_PROXIMITY;
366 case SENSOR_TYPE_PRESSURE:
367 return SENSOR_STRING_TYPE_PRESSURE;
369 case SENSOR_TYPE_RELATIVE_HUMIDITY:
370 return SENSOR_STRING_TYPE_RELATIVE_HUMIDITY;
377 flag_t sensor_get_flags (int s)
381 switch (sensor_info[s].type) {
382 case SENSOR_TYPE_ACCELEROMETER:
383 case SENSOR_TYPE_MAGNETIC_FIELD:
384 case SENSOR_TYPE_ORIENTATION:
385 case SENSOR_TYPE_GYROSCOPE:
386 case SENSOR_TYPE_GYROSCOPE_UNCALIBRATED:
387 case SENSOR_TYPE_PRESSURE:
388 flags |= SENSOR_FLAG_CONTINUOUS_MODE;
391 case SENSOR_TYPE_LIGHT:
392 case SENSOR_TYPE_AMBIENT_TEMPERATURE:
393 case SENSOR_TYPE_TEMPERATURE:
394 case SENSOR_TYPE_RELATIVE_HUMIDITY:
395 flags |= SENSOR_FLAG_ON_CHANGE_MODE;
399 case SENSOR_TYPE_PROXIMITY:
400 flags |= SENSOR_FLAG_WAKE_UP;
401 flags |= SENSOR_FLAG_ON_CHANGE_MODE;
405 ALOGI("Unknown sensor");
410 int get_cdd_freq (int s, int must)
412 switch (sensor_info[s].type) {
413 case SENSOR_TYPE_ACCELEROMETER:
414 return (must ? 100 : 200); /* must 100 Hz, should 200 Hz, CDD compliant */
415 case SENSOR_TYPE_GYROSCOPE:
416 case SENSOR_TYPE_GYROSCOPE_UNCALIBRATED:
417 return (must ? 200 : 200); /* must 200 Hz, should 200 Hz, CDD compliant */
418 case SENSOR_TYPE_MAGNETIC_FIELD:
419 return (must ? 10 : 50); /* must 10 Hz, should 50 Hz, CDD compliant */
420 case SENSOR_TYPE_LIGHT:
421 case SENSOR_TYPE_AMBIENT_TEMPERATURE:
422 case SENSOR_TYPE_TEMPERATURE:
423 return (must ? 1 : 2); /* must 1 Hz, should 2Hz, not mentioned in CDD */
429 /* This value is defined only for continuous mode and on-change sensors. It is the delay between
430 * two sensor events corresponding to the lowest frequency that this sensor supports. When lower
431 * frequencies are requested through batch()/setDelay() the events will be generated at this
432 * frequency instead. It can be used by the framework or applications to estimate when the batch
435 * NOTE: 1) period_ns is in nanoseconds where as maxDelay/minDelay are in microseconds.
436 * continuous, on-change: maximum sampling period allowed in microseconds.
437 * one-shot, special : 0
438 * 2) maxDelay should always fit within a 32 bit signed integer. It is declared as 64 bit
439 * on 64 bit architectures only for binary compatibility reasons.
440 * Availability: SENSORS_DEVICE_API_VERSION_1_3
442 max_delay_t sensor_get_max_delay (int s)
444 char avail_sysfs_path[PATH_MAX];
445 int dev_num = sensor_info[s].dev_num;
448 float min_supported_rate = 1000;
452 /* continuous, on-change: maximum sampling period allowed in microseconds.
453 * one-shot, special : 0
455 if (REPORTING_MODE(sensor_desc[s].flags) == SENSOR_FLAG_ONE_SHOT_MODE ||
456 REPORTING_MODE(sensor_desc[s].flags) == SENSOR_FLAG_SPECIAL_REPORTING_MODE)
459 sprintf(avail_sysfs_path, DEVICE_AVAIL_FREQ_PATH, dev_num);
461 if (sysfs_read_str(avail_sysfs_path, freqs_buf, sizeof(freqs_buf)) < 0) {
462 /* If poll mode sensor */
463 if (!sensor_info[s].num_channels) {
465 min_supported_rate = get_cdd_freq(s, 1);
469 while (*cursor && cursor[0]) {
471 /* Decode a single value */
472 sr = strtod(cursor, NULL);
474 if (sr < min_supported_rate)
475 min_supported_rate = sr;
478 while (cursor[0] && !isspace(cursor[0]))
482 while (cursor[0] && isspace(cursor[0]))
487 /* Check if a minimum rate was specified for this sensor */
488 rate_cap = sensor_get_min_freq(s);
490 if (min_supported_rate < rate_cap)
491 min_supported_rate = rate_cap;
493 /* return 0 for wrong values */
494 if (min_supported_rate < 0.1)
497 /* Return microseconds */
498 return (max_delay_t)(1000000.0 / min_supported_rate);
501 /* this value depends on the reporting mode:
503 * continuous: minimum sample period allowed in microseconds
506 * special : 0, unless otherwise noted
508 int32_t sensor_get_min_delay(int s)
510 char avail_sysfs_path[PATH_MAX];
511 int dev_num = sensor_info[s].dev_num;
514 float max_supported_rate = 0;
517 /* continuous: minimum sampling period allowed in microseconds.
518 * on-change, special : 0
521 if (REPORTING_MODE(sensor_desc[s].flags) == SENSOR_FLAG_ON_CHANGE_MODE ||
522 REPORTING_MODE(sensor_desc[s].flags) == SENSOR_FLAG_SPECIAL_REPORTING_MODE)
525 if (REPORTING_MODE(sensor_desc[s].flags) == SENSOR_FLAG_ONE_SHOT_MODE)
528 sprintf(avail_sysfs_path, DEVICE_AVAIL_FREQ_PATH, dev_num);
530 if (sysfs_read_str(avail_sysfs_path, freqs_buf, sizeof(freqs_buf)) < 0) {
531 /* If poll mode sensor */
532 if (!sensor_info[s].num_channels) {
533 /* The should rate */
534 max_supported_rate = get_cdd_freq(s, 0);
538 while (*cursor && cursor[0]) {
540 /* Decode a single value */
541 sr = strtod(cursor, NULL);
543 if (sr > max_supported_rate && sr <= sensor_get_max_freq(s))
544 max_supported_rate = sr;
547 while (cursor[0] && !isspace(cursor[0]))
551 while (cursor[0] && isspace(cursor[0]))
556 /* return 0 for wrong values */
557 if (max_supported_rate < 0.1)
560 /* Return microseconds */
561 return (int32_t)(1000000.0 / max_supported_rate);