2 * Copyright (C) 2014 Intel Corporation.
8 #include <cutils/properties.h>
9 #include <hardware/sensors.h>
11 #include "transform.h"
13 #include "calibration.h"
15 /*----------------------------------------------------------------------------*/
17 /* Macros related to Intel Sensor Hub */
19 #define GRAVITY 9.80665f
23 #define NUMOFACCDATA (8.0f)
25 /* conversion of acceleration data to SI units (m/s^2) */
26 #define CONVERT_A (GRAVITY_EARTH / LSG / NUMOFACCDATA)
27 #define CONVERT_A_X(x) ((float(x)/1000) * (GRAVITY * -1.0))
28 #define CONVERT_A_Y(x) ((float(x)/1000) * (GRAVITY * 1.0))
29 #define CONVERT_A_Z(x) ((float(x)/1000) * (GRAVITY * 1.0))
31 /* conversion of magnetic data to uT units */
32 #define CONVERT_M (1.0f/6.6f)
33 #define CONVERT_M_X (-CONVERT_M)
34 #define CONVERT_M_Y (-CONVERT_M)
35 #define CONVERT_M_Z (CONVERT_M)
37 #define CONVERT_GAUSS_TO_MICROTESLA(x) ( (x) * 100 )
39 /* conversion of orientation data to degree units */
40 #define CONVERT_O (1.0f/64.0f)
41 #define CONVERT_O_A (CONVERT_O)
42 #define CONVERT_O_P (CONVERT_O)
43 #define CONVERT_O_R (-CONVERT_O)
45 /*conversion of gyro data to SI units (radian/sec) */
46 #define CONVERT_GYRO ((2000.0f/32767.0f)*((float)M_PI / 180.0f))
47 #define CONVERT_GYRO_X (-CONVERT_GYRO)
48 #define CONVERT_GYRO_Y (-CONVERT_GYRO)
49 #define CONVERT_GYRO_Z (CONVERT_GYRO)
51 #define BIT(x) (1 << (x))
53 inline unsigned int set_bit_range(int start, int end)
56 unsigned int value = 0;
58 for (i = start; i < end; ++i)
63 inline float convert_from_vtf_format(int size, int exponent, unsigned int value)
70 value = value & set_bit_range(0, size*8);
71 if (value & BIT(size*8-1)) {
72 value = ((1LL << (size*8)) - value);
77 exponent = abs(exponent);
78 for (i = 0; i < exponent; ++i) {
81 return mul * sample/divider;
83 return mul * sample * pow(10.0, exponent);
87 // Platform sensor orientation
88 #define DEF_ORIENT_ACCEL_X -1
89 #define DEF_ORIENT_ACCEL_Y -1
90 #define DEF_ORIENT_ACCEL_Z -1
92 #define DEF_ORIENT_GYRO_X 1
93 #define DEF_ORIENT_GYRO_Y 1
94 #define DEF_ORIENT_GYRO_Z 1
97 #define CONVERT_FROM_VTF16(s,d,x) (convert_from_vtf_format(s,d,x))
98 #define CONVERT_A_G_VTF16E14_X(s,d,x) (DEF_ORIENT_ACCEL_X *\
99 convert_from_vtf_format(s,d,x)*GRAVITY)
100 #define CONVERT_A_G_VTF16E14_Y(s,d,x) (DEF_ORIENT_ACCEL_Y *\
101 convert_from_vtf_format(s,d,x)*GRAVITY)
102 #define CONVERT_A_G_VTF16E14_Z(s,d,x) (DEF_ORIENT_ACCEL_Z *\
103 convert_from_vtf_format(s,d,x)*GRAVITY)
105 // Degree/sec to radian/sec
106 #define CONVERT_G_D_VTF16E14_X(s,d,x) (DEF_ORIENT_GYRO_X *\
107 convert_from_vtf_format(s,d,x) * \
108 ((float)M_PI/180.0f))
109 #define CONVERT_G_D_VTF16E14_Y(s,d,x) (DEF_ORIENT_GYRO_Y *\
110 convert_from_vtf_format(s,d,x) * \
111 ((float)M_PI/180.0f))
112 #define CONVERT_G_D_VTF16E14_Z(s,d,x) (DEF_ORIENT_GYRO_Z *\
113 convert_from_vtf_format(s,d,x) * \
114 ((float)M_PI/180.0f))
116 // Milli gauss to micro tesla
117 #define CONVERT_M_MG_VTF16E14_X(s,d,x) (convert_from_vtf_format(s,d,x)/10)
118 #define CONVERT_M_MG_VTF16E14_Y(s,d,x) (convert_from_vtf_format(s,d,x)/10)
119 #define CONVERT_M_MG_VTF16E14_Z(s,d,x) (convert_from_vtf_format(s,d,x)/10)
122 /*----------------------------------------------------------------------------*/
124 static int64_t sample_as_int64(unsigned char* sample, struct datum_info_t* type)
130 int zeroed_bits = type->storagebits - type->realbits;
134 if (type->endianness == 'b')
135 for (i=0; i<type->storagebits/8; i++)
136 u64 = (u64 << 8) | sample[i];
138 for (i=type->storagebits/8 - 1; i>=0; i--)
139 u64 = (u64 << 8) | sample[i];
141 u64 = (u64 >> type->shift) & (~0ULL >> zeroed_bits);
143 if (type->sign == 'u')
144 return (int64_t) u64; /* We don't handle unsigned 64 bits int */
146 switch (type->realbits) {
148 return (int64_t) (int8_t) u64;
151 return (int64_t) (u64 >> 11) ?
152 (((int64_t)-1) ^ 0xfff) | u64 : u64;
155 return (int64_t) (int16_t) u64;
158 return (int64_t) (int32_t) u64;
161 return (int64_t) u64;
164 ALOGE("Unhandled sample storage size\n");
169 static int finalize_sample_default(int s, struct sensors_event_t* data)
171 int i = sensor_info[s].catalog_index;
172 int sensor_type = sensor_catalog[i].type;
174 switch (sensor_type) {
175 case SENSOR_TYPE_ACCELEROMETER:
178 case SENSOR_TYPE_MAGNETIC_FIELD:
179 calibrate_compass (data, &sensor_info[s], get_timestamp());
182 case SENSOR_TYPE_GYROSCOPE:
183 calibrate_gyro(data, &sensor_info[s]);
186 case SENSOR_TYPE_LIGHT:
187 case SENSOR_TYPE_AMBIENT_TEMPERATURE:
188 case SENSOR_TYPE_TEMPERATURE:
189 /* Only keep two decimals for these readings */
190 data->data[0] = 0.01 * ((int) (data->data[0] * 100));
193 * These are on change sensors ; drop the sample if it
194 * has the same value as the previously reported one.
196 if (data->data[0] == sensor_info[s].prev_val)
199 sensor_info[s].prev_val = data->data[0];
203 return 1; /* Return sample to Android */
207 static float transform_sample_default(int s, int c, unsigned char* sample_data)
209 struct datum_info_t* sample_type = &sensor_info[s].channel[c].type_info;
210 int64_t s64 = sample_as_int64(sample_data, sample_type);
211 float scale = sensor_info[s].scale ?
212 sensor_info[s].scale : sensor_info[s].channel[c].scale;
214 /* In case correction has been requested using properties, apply it */
215 scale *= sensor_info[s].channel[c].opt_scale;
217 /* Apply default scaling rules */
218 return (sensor_info[s].offset + s64) * scale;
222 static int finalize_sample_ISH(int s, struct sensors_event_t* data)
224 int i = sensor_info[s].catalog_index;
225 int sensor_type = sensor_catalog[i].type;
226 float pitch, roll, yaw;
228 if (sensor_type == SENSOR_TYPE_ORIENTATION) {
230 pitch = data->data[0];
231 roll = data->data[1];
234 data->data[0] = 360.0 - yaw;
235 data->data[1] = -pitch;
236 data->data[2] = -roll;
239 return 1; /* Return sample to Android */
243 static float transform_sample_ISH(int s, int c, unsigned char* sample_data)
245 struct datum_info_t* sample_type = &sensor_info[s].channel[c].type_info;
246 int val = (int) sample_as_int64(sample_data, sample_type);
247 int i = sensor_info[s].catalog_index;
248 int sensor_type = sensor_catalog[i].type;
250 int data_bytes = (sample_type->realbits)/8;
251 int exponent = sensor_info[s].offset;
253 /* In case correction has been requested using properties, apply it */
254 correction = sensor_info[s].channel[c].opt_scale;
256 switch (sensor_type) {
257 case SENSOR_TYPE_ACCELEROMETER:
261 CONVERT_A_G_VTF16E14_X(
262 data_bytes, exponent, val);
266 CONVERT_A_G_VTF16E14_Y(
267 data_bytes, exponent, val);
271 CONVERT_A_G_VTF16E14_Z(
272 data_bytes, exponent, val);
277 case SENSOR_TYPE_GYROSCOPE:
281 CONVERT_G_D_VTF16E14_X(
282 data_bytes, exponent, val);
286 CONVERT_G_D_VTF16E14_Y(
287 data_bytes, exponent, val);
291 CONVERT_G_D_VTF16E14_Z(
292 data_bytes, exponent, val);
296 case SENSOR_TYPE_MAGNETIC_FIELD:
300 CONVERT_M_MG_VTF16E14_X(
301 data_bytes, exponent, val);
305 CONVERT_M_MG_VTF16E14_Y(
306 data_bytes, exponent, val);
310 CONVERT_M_MG_VTF16E14_Z(
311 data_bytes, exponent, val);
315 case SENSOR_TYPE_LIGHT:
318 case SENSOR_TYPE_ORIENTATION:
319 return correction * convert_from_vtf_format(
320 data_bytes, exponent, val);
322 case SENSOR_TYPE_ROTATION_VECTOR:
323 return correction * convert_from_vtf_format(
324 data_bytes, exponent, val);
331 void select_transform (int s)
333 char prop_name[PROP_NAME_MAX];
334 char prop_val[PROP_VALUE_MAX];
335 int i = sensor_info[s].catalog_index;
336 const char *prefix = sensor_catalog[i].tag;
338 sprintf(prop_name, PROP_BASE, prefix, "transform");
340 if (property_get(prop_name, prop_val, "")) {
341 if (!strcmp(prop_val, "ISH")) {
342 ALOGI( "Using Intel Sensor Hub semantics on %s\n",
343 sensor_info[s].friendly_name);
345 sensor_info[s].ops.transform = transform_sample_ISH;
346 sensor_info[s].ops.finalize = finalize_sample_ISH;
351 sensor_info[s].ops.transform = transform_sample_default;
352 sensor_info[s].ops.finalize = finalize_sample_default;
356 float acquire_immediate_value(int s, int c)
358 char sysfs_path[PATH_MAX];
361 int dev_num = sensor_info[s].dev_num;
362 int i = sensor_info[s].catalog_index;
363 const char* raw_path = sensor_catalog[i].channel[c].raw_path;
364 const char* input_path = sensor_catalog[i].channel[c].input_path;
365 float scale = sensor_info[s].scale ?
366 sensor_info[s].scale : sensor_info[s].channel[c].scale;
367 float offset = sensor_info[s].offset;
368 int sensor_type = sensor_catalog[i].type;
371 /* In case correction has been requested using properties, apply it */
372 correction = sensor_info[s].channel[c].opt_scale;
374 /* Acquire a sample value for sensor s / channel c through sysfs */
377 sprintf(sysfs_path, BASE_PATH "%s", dev_num, input_path);
378 ret = sysfs_read_float(sysfs_path, &val);
381 return val * correction;
388 sprintf(sysfs_path, BASE_PATH "%s", dev_num, raw_path);
389 ret = sysfs_read_float(sysfs_path, &val);
395 There is no transform ops defined yet for Raw sysfs values
396 Use this function to perform transformation as well.
398 if (sensor_type == SENSOR_TYPE_MAGNETIC_FIELD)
399 return CONVERT_GAUSS_TO_MICROTESLA ((val + offset) * scale) *
402 return (val + offset) * scale * correction;