description.c

   1 /*
   2  * Copyright (C) 2014 Intel Corporation.
   3  */
   4
   5 #include <stdlib.h>
   6 #include <utils/Log.h>
   7 #include <cutils/properties.h>
   8 #include <hardware/sensors.h>
   9 #include "enumeration.h"
  10
  11 /*
  12  * This information should be provided on a sensor basis through a configuration
  13  * file, or we should build a catalog of known sensors.
  14  */
  15
  16 #define IIO_SENSOR_HAL_VERSION  1
  17
  18
  19 static int sensor_get_st_prop (int s, const char* sel, char val[MAX_NAME_SIZE])
  20 {
  21         char prop_name[PROP_NAME_MAX];
  22         char prop_val[PROP_VALUE_MAX];
  23         int i                   = sensor_info[s].catalog_index;
  24         const char *prefix      = sensor_catalog[i].tag;
  25
  26         sprintf(prop_name, PROP_BASE, prefix, sel);
  27
  28         if (property_get(prop_name, prop_val, "")) {
  29                 strncpy(val, prop_val, MAX_NAME_SIZE-1);
  30                 val[MAX_NAME_SIZE-1] = '\0';
  31                 return 0;
  32         }
  33
  34         return -1;
  35 }
  36
  37
  38 static int sensor_get_fl_prop (int s, const char* sel, float* val)
  39 {
  40         char buf[MAX_NAME_SIZE];
  41
  42         if (sensor_get_st_prop(s, sel, buf))
  43                 return -1;
  44
  45         *val = (float) strtod(buf, NULL);
  46         return 0;
  47 }
  48
  49
  50 char* sensor_get_name (int s)
  51 {
  52         if (sensor_info[s].friendly_name[0] != '\0' ||
  53                 !sensor_get_st_prop(s, "name", sensor_info[s].friendly_name))
  54                         return sensor_info[s].friendly_name;
  55
  56         /* If we got a iio device name from sysfs, use it */
  57         if (sensor_info[s].internal_name[0]) {
  58                 snprintf(sensor_info[s].friendly_name, MAX_NAME_SIZE, "S%d-%s",
  59                          s, sensor_info[s].internal_name);
  60                 sensor_info[s].friendly_name[MAX_NAME_SIZE-1] = '\0';
  61         } else {
  62                 sprintf(sensor_info[s].friendly_name, "S%d", s);
  63         }
  64
  65         return sensor_info[s].friendly_name;
  66 }
  67
  68
  69 char* sensor_get_vendor (int s)
  70 {
  71         if (sensor_info[s].vendor_name[0] ||
  72                 !sensor_get_st_prop(s, "vendor", sensor_info[s].vendor_name))
  73                         return sensor_info[s].vendor_name;
  74
  75         return "";
  76 }
  77
  78
  79 int sensor_get_version (int s)
  80 {
  81         return IIO_SENSOR_HAL_VERSION;
  82 }
  83
  84
  85 float sensor_get_max_range (int s)
  86 {
  87         int catalog_index;
  88         int sensor_type;
  89
  90         if (sensor_info[s].max_range != 0.0 ||
  91                 !sensor_get_fl_prop(s, "max_range", &sensor_info[s].max_range))
  92                         return sensor_info[s].max_range;
  93
  94         /* Try returning a sensible value given the sensor type */
  95
  96         /* We should cap returned samples accordingly... */
  97
  98         catalog_index = sensor_info[s].catalog_index;
  99         sensor_type = sensor_catalog[catalog_index].type;
 100
 101         switch (sensor_type) {
 102                 case SENSOR_TYPE_ACCELEROMETER:         /* m/s^2        */
 103                         return 50;
 104
 105                 case SENSOR_TYPE_MAGNETIC_FIELD:        /* micro-tesla  */
 106                         return 500;
 107
 108                 case SENSOR_TYPE_ORIENTATION:           /* degrees      */
 109                         return 360;
 110
 111                 case SENSOR_TYPE_GYROSCOPE:             /* radians/s    */
 112                         return 10;
 113
 114                 case SENSOR_TYPE_LIGHT:                 /* SI lux units */
 115                         return 50000;
 116
 117                 case SENSOR_TYPE_AMBIENT_TEMPERATURE:   /* °C          */
 118                 case SENSOR_TYPE_TEMPERATURE:           /* °C          */
 119                 case SENSOR_TYPE_PROXIMITY:             /* centimeters  */
 120                 case SENSOR_TYPE_PRESSURE:              /* hecto-pascal */
 121                 case SENSOR_TYPE_RELATIVE_HUMIDITY:     /* percent */
 122                         return 100;
 123
 124                 default:
 125                         return 0.0;
 126                 }
 127 }
 128
 129
 130 float sensor_get_resolution (int s)
 131 {
 132         if (sensor_info[s].resolution != 0.0 ||
 133                 !sensor_get_fl_prop(s, "resolution", &sensor_info[s].resolution))
 134                         return sensor_info[s].resolution;
 135
 136         return 0;
 137 }
 138
 139
 140 float sensor_get_power (int s)
 141 {
 142         /* mA used while sensor is in use ; not sure about volts :) */
 143         if (sensor_info[s].power != 0.0 ||
 144                 !sensor_get_fl_prop(s, "power", &sensor_info[s].power))
 145                         return sensor_info[s].power;
 146
 147         return 0;
 148 }