/*
- * Copyright (C) 2014 Intel Corporation.
+ * Copyright (C) 2014-2015 Intel Corporation.
*/
#include <stdlib.h>
+#include <ctype.h>
#include <utils/Log.h>
#include <cutils/properties.h>
#include <hardware/sensors.h>
+#include "common.h"
#include "enumeration.h"
+#include "description.h"
+#include "utils.h"
#define IIO_SENSOR_HAL_VERSION 1
+#define MIN_ON_CHANGE_SAMPLING_PERIOD_US 200000 /* For on change sensors (temperature, proximity, ALS, etc.) report we support 5 Hz max (0.2 s min period) */
+#define MAX_ON_CHANGE_SAMPLING_PERIOD_US 10000000 /* 0.1 Hz min (10 s max period)*/
+#define ANDROID_MAX_FREQ 1000 /* 1000 Hz - This is how much Android requests for the fastest frequency */
-static int sensor_get_st_prop (int s, const char* sel, char val[MAX_NAME_SIZE])
+/*
+ * About properties
+ *
+ * We acquire a number of parameters about sensors by reading properties.
+ * The idea here is that someone (either a script, or daemon, sets them
+ * depending on the set of sensors present on the machine.
+ *
+ * There are fallback paths in case the properties are not defined, but it is
+ * highly desirable to at least have the following for each sensor:
+ *
+ * ro.iio.anglvel.name = Gyroscope
+ * ro.iio.anglvel.vendor = Intel
+ * ro.iio.anglvel.max_range = 35
+ * ro.iio.anglvel.resolution = 0.002
+ * ro.iio.anglvel.power = 6.1
+ *
+ * Besides these, we have a couple of knobs initially used to cope with Intel
+ * Sensor Hub oddities, such as HID inspired units or firmware bugs:
+ *
+ * ro.iio.anglvel.transform = ISH
+ * ro.iio.anglvel.quirks = init-rate
+ *
+ * The "terse" quirk indicates that the underlying driver only sends events
+ * when the sensor reports a change. The HAL then periodically generates
+ * duplicate events so the sensor behaves as a continously firing one.
+ *
+ * The "noisy" quirk indicates that the underlying driver has a unusually high
+ * level of noise in its readings, and that the HAL has to accomodate it
+ * somehow, e.g. in the magnetometer calibration code path.
+ *
+ * This one is used specifically to pass a calibration scale to ALS drivers:
+ *
+ * ro.iio.illuminance.name = CPLM3218x Ambient Light Sensor
+ * ro.iio.illuminance.vendor = Capella Microsystems
+ * ro.iio.illuminance.max_range = 167000
+ * ro.iio.illuminance.resolution = 1
+ * ro.iio.illuminance.power = .001
+ * ro.iio.illuminance.illumincalib = 7400
+ *
+ * There's a 'opt_scale' specifier, documented as follows:
+ *
+ * This adds support for a scaling factor that can be expressed
+ * using properties, for all sensors, on a channel basis. That
+ * scaling factor is applied after all other transforms have been
+ * applied, and is intended as a way to compensate for problems
+ * such as an incorrect axis polarity for a given sensor.
+ *
+ * The syntax is <usual property prefix>.<channel>.opt_scale, e.g.
+ * ro.iio.accel.y.opt_scale = -1 to negate the sign of the y readings
+ * for the accelerometer.
+ *
+ * For sensors using a single channel - and only those - the channel
+ * name is implicitly void and a syntax such as ro.iio.illuminance.
+ * opt_scale = 3 has to be used.
+ *
+ * 'panel' and 'rotation' specifiers can be used to express ACPI PLD placement
+ * information ; if found they will be used in priority over the actual ACPI
+ * data. That is intended as a way to verify values during development.
+ *
+ * It's possible to use the contents of the iio device name as a way to
+ * discriminate between sensors. Several sensors of the same type can coexist:
+ * e.g. ro.iio.temp.bmg160.name = BMG160 Thermometer will be used in priority
+ * over ro.iio.temp.name = BMC150 Thermometer if the sensor for which we query
+ * properties values happen to have its iio device name set to bmg160.
+ */
+
+int sensor_get_st_prop (int s, const char* sel, char val[MAX_NAME_SIZE])
{
char prop_name[PROP_NAME_MAX];
char prop_val[PROP_VALUE_MAX];
- int i = sensor_info[s].catalog_index;
+ char extended_sel[PROP_VALUE_MAX];
+
+ int i = sensor[s].catalog_index;
const char *prefix = sensor_catalog[i].tag;
+ const char *shorthand = sensor_catalog[i].shorthand;
- sprintf(prop_name, PROP_BASE, prefix, sel);
+ /* First try most specialized form, like ro.iio.anglvel.bmg160.name */
+
+ snprintf(extended_sel, PROP_NAME_MAX, "%s.%s",
+ sensor[s].internal_name, sel);
+
+ snprintf(prop_name, PROP_NAME_MAX, PROP_BASE, prefix, extended_sel);
+
+ if (property_get(prop_name, prop_val, "")) {
+ strncpy(val, prop_val, MAX_NAME_SIZE-1);
+ val[MAX_NAME_SIZE-1] = '\0';
+ return 0;
+ }
+
+ if (shorthand[0] != '\0') {
+ /* Try with shorthand instead of prefix */
+ snprintf(prop_name, PROP_NAME_MAX, PROP_BASE, shorthand, extended_sel);
+
+ if (property_get(prop_name, prop_val, "")) {
+ strncpy(val, prop_val, MAX_NAME_SIZE-1);
+ val[MAX_NAME_SIZE-1] = '\0';
+ return 0;
+ }
+ }
+ /* Fall back to simple form, like ro.iio.anglvel.name */
+
+ snprintf(prop_name, PROP_NAME_MAX, PROP_BASE, prefix, sel);
if (property_get(prop_name, prop_val, "")) {
strncpy(val, prop_val, MAX_NAME_SIZE-1);
}
-static int sensor_get_fl_prop (int s, const char* sel, float* val)
+int sensor_get_prop (int s, const char* sel, int* val)
+{
+ char buf[MAX_NAME_SIZE];
+
+ if (sensor_get_st_prop(s, sel, buf))
+ return -1;
+
+ *val = atoi(buf);
+ return 0;
+}
+
+
+int sensor_get_fl_prop (int s, const char* sel, float* val)
{
char buf[MAX_NAME_SIZE];
char* sensor_get_name (int s)
{
- if (sensor_info[s].friendly_name[0] != '\0' ||
- !sensor_get_st_prop(s, "name", sensor_info[s].friendly_name))
- return sensor_info[s].friendly_name;
+ char buf[MAX_NAME_SIZE];
+
+ if (sensor[s].is_virtual) {
+ switch (sensor[s].type) {
+ case SENSOR_TYPE_GYROSCOPE_UNCALIBRATED:
+ case SENSOR_TYPE_MAGNETIC_FIELD_UNCALIBRATED:
+ strcpy(buf, sensor[sensor[s].base[0]].friendly_name);
+ snprintf(sensor[s].friendly_name,
+ MAX_NAME_SIZE,
+ "%s %s", "Uncalibrated", buf);
+ return sensor[s].friendly_name;
+
+ default:
+ return "";
+ }
+ }
+
+ if (sensor[s].friendly_name[0] != '\0' ||
+ !sensor_get_st_prop(s, "name", sensor[s].friendly_name))
+ return sensor[s].friendly_name;
/* If we got a iio device name from sysfs, use it */
- if (sensor_info[s].internal_name[0]) {
- snprintf(sensor_info[s].friendly_name, MAX_NAME_SIZE, "S%d-%s",
- s, sensor_info[s].internal_name);
- sensor_info[s].friendly_name[MAX_NAME_SIZE-1] = '\0';
+ if (sensor[s].internal_name[0]) {
+ snprintf(sensor[s].friendly_name, MAX_NAME_SIZE, "S%d-%s",
+ s, sensor[s].internal_name);
} else {
- sprintf(sensor_info[s].friendly_name, "S%d", s);
+ sprintf(sensor[s].friendly_name, "S%d", s);
}
- return sensor_info[s].friendly_name;
+ return sensor[s].friendly_name;
}
char* sensor_get_vendor (int s)
{
- if (sensor_info[s].vendor_name[0] ||
- !sensor_get_st_prop(s, "vendor", sensor_info[s].vendor_name))
- return sensor_info[s].vendor_name;
+ if (sensor[s].is_virtual) {
+ switch (sensor[s].type) {
+ case SENSOR_TYPE_GYROSCOPE_UNCALIBRATED:
+ case SENSOR_TYPE_MAGNETIC_FIELD_UNCALIBRATED:
+ return sensor[sensor[s].base[0]].vendor_name;
+ break;
+
+ default:
+ return "";
+
+ }
+ }
+
+ if (sensor[s].vendor_name[0] ||
+ !sensor_get_st_prop(s, "vendor", sensor[s].vendor_name))
+ return sensor[s].vendor_name;
return "";
}
-int sensor_get_version (int s)
+int sensor_get_version (__attribute__((unused)) int s)
{
return IIO_SENSOR_HAL_VERSION;
}
float sensor_get_max_range (int s)
{
- int catalog_index;
- int sensor_type;
+ if (sensor[s].is_virtual) {
+ switch (sensor[s].type) {
+ case SENSOR_TYPE_GYROSCOPE_UNCALIBRATED:
+ case SENSOR_TYPE_MAGNETIC_FIELD_UNCALIBRATED:
+ return sensor[sensor[s].base[0]].max_range;
+
+ default:
+ return 0.0;
+ }
+ }
- if (sensor_info[s].max_range != 0.0 ||
- !sensor_get_fl_prop(s, "max_range", &sensor_info[s].max_range))
- return sensor_info[s].max_range;
+ if (sensor[s].max_range != 0.0 ||
+ !sensor_get_fl_prop(s, "max_range", &sensor[s].max_range))
+ return sensor[s].max_range;
/* Try returning a sensible value given the sensor type */
/* We should cap returned samples accordingly... */
- catalog_index = sensor_info[s].catalog_index;
- sensor_type = sensor_catalog[catalog_index].type;
-
- switch (sensor_type) {
+ switch (sensor_desc[s].type) {
case SENSOR_TYPE_ACCELEROMETER: /* m/s^2 */
return 50;
return 100;
default:
- return 0.0;
+ return 0;
}
}
+static float sensor_get_min_freq (int s)
+{
+ /*
+ * Check if a low cap has been specified for this sensor sampling rate.
+ * In some case, even when the driver supports lower rate, we still
+ * wish to receive a certain number of samples per seconds for various
+ * reasons (calibration, filtering, no change in power consumption...).
+ */
+
+ float min_freq;
+
+ if (!sensor_get_fl_prop(s, "min_freq", &min_freq))
+ return min_freq;
+
+ return 0;
+}
+
+
+static float sensor_get_max_freq (int s)
+{
+ float max_freq;
+
+ if (!sensor_get_fl_prop(s, "max_freq", &max_freq))
+ return max_freq;
+
+ return ANDROID_MAX_FREQ;
+}
+
+int sensor_get_cal_steps (int s)
+{
+ int cal_steps;
+ if (!sensor_get_prop(s, "cal_steps", &cal_steps))
+ return cal_steps;
+
+ return 0;
+}
float sensor_get_resolution (int s)
{
- if (sensor_info[s].resolution != 0.0 ||
- !sensor_get_fl_prop(s, "resolution", &sensor_info[s].resolution))
- return sensor_info[s].resolution;
+ if (sensor[s].is_virtual) {
+ switch (sensor[s].type) {
+ case SENSOR_TYPE_GYROSCOPE_UNCALIBRATED:
+ case SENSOR_TYPE_MAGNETIC_FIELD_UNCALIBRATED:
+ return sensor[sensor[s].base[0]].resolution;
+
+ default:
+ return 0;
+ }
+ }
+
+ if (sensor[s].resolution != 0.0 ||
+ !sensor_get_fl_prop(s, "resolution", &sensor[s].resolution))
+ return sensor[s].resolution;
return 0;
}
float sensor_get_power (int s)
{
+
+ if (sensor[s].is_virtual) {
+ switch (sensor[s].type) {
+ case SENSOR_TYPE_GYROSCOPE_UNCALIBRATED:
+ case SENSOR_TYPE_MAGNETIC_FIELD_UNCALIBRATED:
+ return sensor[sensor[s].base[0]].power;
+
+ default:
+ return 0;
+ }
+ }
+
/* mA used while sensor is in use ; not sure about volts :) */
- if (sensor_info[s].power != 0.0 ||
- !sensor_get_fl_prop(s, "power", &sensor_info[s].power))
- return sensor_info[s].power;
+ if (sensor[s].power != 0.0 ||
+ !sensor_get_fl_prop(s, "power", &sensor[s].power))
+ return sensor[s].power;
+
+ return 0;
+}
+
+
+float sensor_get_illumincalib (int s)
+{
+ /* calibrating the ALS Sensor*/
+ if (sensor[s].illumincalib != 0.0 ||
+ !sensor_get_fl_prop(s, "illumincalib", &sensor[s].illumincalib)) {
+ return sensor[s].illumincalib;
+ }
return 0;
}
+
+
+uint32_t sensor_get_quirks (int s)
+{
+ char quirks_buf[MAX_NAME_SIZE];
+
+ /* Read and decode quirks property on first reference */
+ if (!(sensor[s].quirks & QUIRK_ALREADY_DECODED)) {
+ quirks_buf[0] = '\0';
+ sensor_get_st_prop(s, "quirks", quirks_buf);
+
+ if (strstr(quirks_buf, "init-rate"))
+ sensor[s].quirks |= QUIRK_INITIAL_RATE;
+
+ if (strstr(quirks_buf, "continuous"))
+ sensor[s].quirks |= QUIRK_FORCE_CONTINUOUS;
+
+ if (strstr(quirks_buf, "terse"))
+ sensor[s].quirks |= QUIRK_TERSE_DRIVER;
+
+ if (strstr(quirks_buf, "noisy"))
+ sensor[s].quirks |= QUIRK_NOISY;
+
+ if (strstr(quirks_buf, "biased"))
+ sensor[s].quirks |= QUIRK_BIASED;
+
+ if (strstr(quirks_buf, "spotty"))
+ sensor[s].quirks |= QUIRK_SPOTTY;
+
+ if (strstr(quirks_buf, "no-event"))
+ sensor[s].quirks |= QUIRK_NO_EVENT_MODE;
+
+ if (strstr(quirks_buf, "no-trig"))
+ sensor[s].quirks |= QUIRK_NO_TRIG_MODE;
+
+ if (strstr(quirks_buf, "no-poll"))
+ sensor[s].quirks |= QUIRK_NO_POLL_MODE;
+
+ if (strstr(quirks_buf, "hrtimer"))
+ sensor[s].quirks |= QUIRK_HRTIMER;
+
+ sensor[s].quirks |= QUIRK_ALREADY_DECODED;
+ }
+
+ return sensor[s].quirks;
+}
+
+
+int sensor_get_order (int s, unsigned char map[MAX_CHANNELS])
+{
+ char buf[MAX_NAME_SIZE];
+ int i;
+ int count = sensor_catalog[sensor[s].catalog_index].num_channels;
+
+ if (sensor_get_st_prop(s, "order", buf))
+ return 0; /* No order property */
+
+ /* Assume ASCII characters, in the '0'..'9' range */
+
+ for (i=0; i<count; i++)
+ if (buf[i] - '0' >= count) {
+ ALOGE("Order index out of range for sensor %d\n", s);
+ return 0;
+ }
+
+ for (i=0; i<count; i++)
+ map[i] = buf[i] - '0';
+
+ return 1; /* OK to use modified ordering map */
+}
+
+int sensor_get_mounting_matrix (int s, float mm[9])
+{
+ int dev_num = sensor[s].dev_num, err, i;
+ char mm_path[PATH_MAX], mm_buf[100];
+ char *tmp1 = mm_buf, *tmp2;
+
+ switch (sensor[s].type) {
+ case SENSOR_TYPE_ACCELEROMETER:
+ case SENSOR_TYPE_MAGNETIC_FIELD:
+ case SENSOR_TYPE_GYROSCOPE:
+ break;
+ default:
+ return 0;
+ }
+
+ sprintf(mm_path, MOUNTING_MATRIX_PATH, dev_num);
+
+ err = sysfs_read_str(mm_path, mm_buf, sizeof(mm_buf));
+ if (err < 0)
+ return 0;
+
+ for(i = 0; i < 9; i++) {
+ float f;
+
+ f = strtof(tmp1, &tmp2);
+ if (!f && tmp1 == tmp2)
+ return 0;
+ mm[i] = f;
+ tmp1 = tmp2 + 1;
+ }
+
+ ALOGI("%s: %f %f %f %f %f %f %f %f %f\n", __func__, mm[0], mm[1], mm[2], mm[3], mm[4], mm[5], mm[6], mm[7], mm[8]);
+ return 1;
+}
+
+
+char* sensor_get_string_type (int s)
+{
+ switch (sensor_desc[s].type) {
+ case SENSOR_TYPE_ACCELEROMETER:
+ return SENSOR_STRING_TYPE_ACCELEROMETER;
+
+ case SENSOR_TYPE_MAGNETIC_FIELD:
+ return SENSOR_STRING_TYPE_MAGNETIC_FIELD;
+
+ case SENSOR_TYPE_MAGNETIC_FIELD_UNCALIBRATED:
+ return SENSOR_STRING_TYPE_MAGNETIC_FIELD_UNCALIBRATED;
+
+ case SENSOR_TYPE_ORIENTATION:
+ return SENSOR_STRING_TYPE_ORIENTATION;
+
+ case SENSOR_TYPE_GYROSCOPE:
+ return SENSOR_STRING_TYPE_GYROSCOPE;
+
+ case SENSOR_TYPE_GYROSCOPE_UNCALIBRATED:
+ return SENSOR_STRING_TYPE_GYROSCOPE_UNCALIBRATED;
+
+ case SENSOR_TYPE_LIGHT:
+ return SENSOR_STRING_TYPE_LIGHT;
+
+ case SENSOR_TYPE_AMBIENT_TEMPERATURE:
+ return SENSOR_STRING_TYPE_AMBIENT_TEMPERATURE;
+
+ case SENSOR_TYPE_TEMPERATURE:
+ return SENSOR_STRING_TYPE_TEMPERATURE;
+
+ case SENSOR_TYPE_PROXIMITY:
+ return SENSOR_STRING_TYPE_PROXIMITY;
+
+ case SENSOR_TYPE_PRESSURE:
+ return SENSOR_STRING_TYPE_PRESSURE;
+
+ case SENSOR_TYPE_RELATIVE_HUMIDITY:
+ return SENSOR_STRING_TYPE_RELATIVE_HUMIDITY;
+
+ default:
+ return "";
+ }
+}
+
+
+flag_t sensor_get_flags (int s)
+{
+ flag_t flags = 0;
+
+ switch (sensor_desc[s].type) {
+ case SENSOR_TYPE_LIGHT:
+ case SENSOR_TYPE_AMBIENT_TEMPERATURE:
+ case SENSOR_TYPE_TEMPERATURE:
+ case SENSOR_TYPE_RELATIVE_HUMIDITY:
+ case SENSOR_TYPE_STEP_COUNTER:
+ flags |= SENSOR_FLAG_ON_CHANGE_MODE;
+ break;
+
+
+ case SENSOR_TYPE_PROXIMITY:
+ flags |= SENSOR_FLAG_WAKE_UP;
+ flags |= SENSOR_FLAG_ON_CHANGE_MODE;
+ break;
+ case SENSOR_TYPE_STEP_DETECTOR:
+ flags |= SENSOR_FLAG_SPECIAL_REPORTING_MODE;
+ break;
+ default:
+ break;
+ }
+ return flags;
+}
+
+
+static int get_cdd_freq (int s, int must)
+{
+ switch (sensor_desc[s].type) {
+ case SENSOR_TYPE_ACCELEROMETER:
+ return (must ? 100 : 200); /* must 100 Hz, should 200 Hz, CDD compliant */
+
+ case SENSOR_TYPE_GYROSCOPE:
+ return (must ? 200 : 200); /* must 200 Hz, should 200 Hz, CDD compliant */
+
+ case SENSOR_TYPE_MAGNETIC_FIELD:
+ return (must ? 10 : 50); /* must 10 Hz, should 50 Hz, CDD compliant */
+
+ case SENSOR_TYPE_LIGHT:
+ case SENSOR_TYPE_AMBIENT_TEMPERATURE:
+ case SENSOR_TYPE_TEMPERATURE:
+ return (must ? 1 : 2); /* must 1 Hz, should 2Hz, not mentioned in CDD */
+
+ default:
+ return 1; /* Use 1 Hz by default, e.g. for proximity */
+ }
+}
+
+/*
+ * This value is defined only for continuous mode and on-change sensors. It is the delay between two sensor events corresponding to the lowest frequency that
+ * this sensor supports. When lower frequencies are requested through batch()/setDelay() the events will be generated at this frequency instead. It can be used
+ * by the framework or applications to estimate when the batch FIFO may be full. maxDelay should always fit within a 32 bit signed integer. It is declared as
+ * 64 bit on 64 bit architectures only for binary compatibility reasons. Availability: SENSORS_DEVICE_API_VERSION_1_3
+ */
+max_delay_t sensor_get_max_delay (int s)
+{
+ char avail_sysfs_path[PATH_MAX];
+ int dev_num = sensor[s].dev_num;
+ char freqs_buf[100];
+ char* cursor;
+ float min_supported_rate = 1000;
+ float rate_cap;
+ float sr;
+
+ /*
+ * continuous, on-change: maximum sampling period allowed in microseconds.
+ * one-shot, special : 0
+ */
+ switch (REPORTING_MODE(sensor_desc[s].flags)) {
+ case SENSOR_FLAG_ONE_SHOT_MODE:
+ case SENSOR_FLAG_SPECIAL_REPORTING_MODE:
+ return 0;
+
+ case SENSOR_FLAG_ON_CHANGE_MODE:
+ return MAX_ON_CHANGE_SAMPLING_PERIOD_US;
+
+ default:
+ break;
+ }
+
+ if (sensor[s].is_virtual) {
+ switch (sensor[s].type) {
+ case SENSOR_TYPE_GYROSCOPE_UNCALIBRATED:
+ case SENSOR_TYPE_MAGNETIC_FIELD_UNCALIBRATED:
+ return sensor_desc[sensor[s].base[0]].maxDelay;
+ default:
+ return 0;
+ }
+ }
+ sprintf(avail_sysfs_path, DEVICE_AVAIL_FREQ_PATH, dev_num);
+
+ if (sysfs_read_str(avail_sysfs_path, freqs_buf, sizeof(freqs_buf)) < 0) {
+ if (sensor[s].mode == MODE_POLL) {
+ /* The must rate */
+ min_supported_rate = get_cdd_freq(s, 1);
+ }
+ } else {
+ cursor = freqs_buf;
+ while (*cursor && cursor[0]) {
+
+ /* Decode a single value */
+ sr = strtod(cursor, NULL);
+
+ if (sr < min_supported_rate)
+ min_supported_rate = sr;
+
+ /* Skip digits */
+ while (cursor[0] && !isspace(cursor[0]))
+ cursor++;
+
+ /* Skip spaces */
+ while (cursor[0] && isspace(cursor[0]))
+ cursor++;
+ }
+ }
+
+ /* Check if a minimum rate was specified for this sensor */
+ rate_cap = sensor_get_min_freq(s);
+
+ if (min_supported_rate < rate_cap)
+ min_supported_rate = rate_cap;
+
+ /* return 0 for wrong values */
+ if (min_supported_rate < 0.1)
+ return 0;
+
+ /* Return microseconds */
+ return (max_delay_t) (1000000.0 / min_supported_rate);
+}
+
+
+int32_t sensor_get_min_delay (int s)
+{
+ char avail_sysfs_path[PATH_MAX];
+ int dev_num = sensor[s].dev_num;
+ char freqs_buf[100];
+ char* cursor;
+ float max_supported_rate = 0;
+ float max_from_prop = sensor_get_max_freq(s);
+ float sr;
+
+ /* continuous, on change: minimum sampling period allowed in microseconds.
+ * special : 0, unless otherwise noted
+ * one-shot:-1
+ */
+ switch (REPORTING_MODE(sensor_desc[s].flags)) {
+ case SENSOR_FLAG_ON_CHANGE_MODE:
+ return MIN_ON_CHANGE_SAMPLING_PERIOD_US;
+
+ case SENSOR_FLAG_SPECIAL_REPORTING_MODE:
+ return 0;
+
+ case SENSOR_FLAG_ONE_SHOT_MODE:
+ return -1;
+
+ default:
+ break;
+ }
+
+ if (sensor[s].is_virtual) {
+ switch (sensor[s].type) {
+ case SENSOR_TYPE_GYROSCOPE_UNCALIBRATED:
+ case SENSOR_TYPE_MAGNETIC_FIELD_UNCALIBRATED:
+ return sensor_desc[sensor[s].base[0]].minDelay;
+ default:
+ return 0;
+ }
+ }
+
+ sprintf(avail_sysfs_path, DEVICE_AVAIL_FREQ_PATH, dev_num);
+
+ if (sysfs_read_str(avail_sysfs_path, freqs_buf, sizeof(freqs_buf)) < 0) {
+ if (sensor[s].mode == MODE_POLL) {
+ /* If we have max specified via a property use it */
+ if (max_from_prop != ANDROID_MAX_FREQ)
+ max_supported_rate = max_from_prop;
+ else
+ /* The should rate */
+ max_supported_rate = get_cdd_freq(s, 0);
+ }
+ } else {
+ cursor = freqs_buf;
+ while (*cursor && cursor[0]) {
+
+ /* Decode a single value */
+ sr = strtod(cursor, NULL);
+
+ if (sr > max_supported_rate && sr <= max_from_prop)
+ max_supported_rate = sr;
+
+ /* Skip digits */
+ while (cursor[0] && !isspace(cursor[0]))
+ cursor++;
+
+ /* Skip spaces */
+ while (cursor[0] && isspace(cursor[0]))
+ cursor++;
+ }
+ }
+
+ /* return 0 for wrong values */
+ if (max_supported_rate < 0.1)
+ return 0;
+
+ /* Return microseconds */
+ return (int32_t) (1000000.0 / max_supported_rate);
+}