#include "utils.h"
#include "transform.h"
#include "calibration.h"
+#include "description.h"
/* Currently active sensors count, per device */
static int poll_sensors_per_dev[MAX_DEVICES]; /* poll-mode sensors */
static int active_poll_sensors; /* Number of enabled poll-mode sensors */
+/* We use pthread condition variables to get worker threads out of sleep */
+static pthread_cond_t thread_release_cond [MAX_SENSORS];
+static pthread_mutex_t thread_release_mutex [MAX_SENSORS];
+
/*
* We associate tags to each of our poll set entries. These tags have the
* following values:
break;
case SENSOR_TYPE_GYROSCOPE:
+ case SENSOR_TYPE_GYROSCOPE_UNCALIBRATED:
gyro_cal_init(&sensor_info[s]);
break;
}
compass_store_data(&sensor_info[s]);
}
+
+ /* If uncalibrated type and pair is already active don't adjust counters */
+ if (sensor_type == SENSOR_TYPE_GYROSCOPE_UNCALIBRATED &&
+ sensor_info[sensor_info[s].pair_idx].enable_count != 0)
+ return 0;
+
/* We changed the state of a sensor - adjust per iio device counters */
/* If this is a regular event-driven sensor */
case SENSOR_TYPE_ACCELEROMETER: /* m/s^2 */
case SENSOR_TYPE_MAGNETIC_FIELD: /* micro-tesla */
case SENSOR_TYPE_ORIENTATION: /* degrees */
+ case SENSOR_TYPE_GYROSCOPE_UNCALIBRATED:
case SENSOR_TYPE_GYROSCOPE: /* radians/s */
return 3;
}
-/* Check and honor termination requests */
-#define CHECK_CANCEL(s) \
- if (sensor_info[s].thread_data_fd[1] == -1) { \
- ALOGV("Acquisition thread for S%d exiting\n", s); \
- pthread_exit(0); \
- }
+static void time_add(struct timespec *out, struct timespec *in, int64_t ns)
+{
+ int64_t target_ts = 1000000000LL * in->tv_sec + in->tv_nsec + ns;
+
+ out->tv_sec = target_ts / 1000000000;
+ out->tv_nsec = target_ts % 1000000000;
+}
static void* acquisition_routine (void* param)
*/
int s = (int) param;
- int report_fd;
int num_fields;
- uint32_t period;
- int64_t entry_ts;
struct sensors_event_t data = {0};
int c;
- int sampling_rate;
int ret;
- uint32_t elapsed;
+ struct timespec entry_time;
+ struct timespec target_time;
+ int64_t period;
ALOGV("Entering data acquisition thread for sensor %d\n", s);
num_fields = get_field_count(s);
- while (1) {
- CHECK_CANCEL(s)
+ /*
+ * Each condition variable is associated to a mutex that has to be
+ * locked by the thread that's waiting on it. We use these condition
+ * variables to get the acquisition threads out of sleep quickly after
+ * the sampling rate is adjusted, or the sensor is disabled.
+ */
+ pthread_mutex_lock(&thread_release_mutex[s]);
+ while (1) {
/* Pinpoint the moment we start sampling */
- entry_ts = get_timestamp();
+ clock_gettime(CLOCK_REALTIME, &entry_time);
ALOGV("Acquiring sample data for sensor %d through sysfs\n", s);
for (c=0; c<num_fields; c++) {
data.data[c] = acquire_immediate_value(s, c);
+ /* Check and honor termination requests */
+ if (sensor_info[s].thread_data_fd[1] == -1)
+ goto exit;
+
ALOGV("\tfield %d: %f\n", c, data.data[c]);
- CHECK_CANCEL(s)
+
}
/* If the sample looks good */
num_fields * sizeof(float));
}
- CHECK_CANCEL(s)
+ /* Check and honor termination requests */
+ if (sensor_info[s].thread_data_fd[1] == -1)
+ goto exit;
+
+
+ period = (int64_t) (1000000000.0/ sensor_info[s].sampling_rate);
- /* Sleep a little, deducting read & write times */
- elapsed = (get_timestamp() - entry_ts) / 1000;
+ time_add(&target_time, &entry_time, period);
- period = (uint32_t)
- (1000000000LL / sensor_info[s].sampling_rate / 1000);
+ /*
+ * Wait until the sampling time elapses, or a rate change is
+ * signaled, or a thread exit is requested.
+ */
+ ret = pthread_cond_timedwait( &thread_release_cond[s],
+ &thread_release_mutex[s],
+ &target_time);
- if (period > elapsed)
- usleep(period - elapsed);
+ /* Check and honor termination requests */
+ if (sensor_info[s].thread_data_fd[1] == -1)
+ goto exit;
}
+exit:
+ ALOGV("Acquisition thread for S%d exiting\n", s);
+ pthread_mutex_unlock(&thread_release_mutex[s]);
+ pthread_exit(0);
return NULL;
}
ALOGV("Initializing acquisition context for sensor %d\n", s);
+ /* Create condition variable and mutex for quick thread release */
+ ret = pthread_cond_init(&thread_release_cond[s], NULL);
+ ret = pthread_mutex_init(&thread_release_mutex[s], NULL);
+
/* Create a pipe for inter thread communication */
ret = pipe(sensor_info[s].thread_data_fd);
/* Delete the incoming side of the pipe from our poll set */
epoll_ctl(poll_fd, EPOLL_CTL_DEL, incoming_data_fd, NULL);
- /* Mark the pipe ends as invalid ; that's a cheap exit signal */
+ /* Mark the pipe ends as invalid ; that's a cheap exit flag */
sensor_info[s].thread_data_fd[0] = -1;
sensor_info[s].thread_data_fd[1] = -1;
close(incoming_data_fd);
close(outgoing_data_fd);
- /* Wait end of thread, and clean up thread handle */
+ /* Stop acquisition thread and clean up thread handle */
+ pthread_cond_signal(&thread_release_cond[s]);
pthread_join(sensor_info[s].acquisition_thread, NULL);
/* Clean up our sensor descriptor */
sensor_info[s].acquisition_thread = -1;
+
+ /* Delete condition variable and mutex */
+ pthread_cond_destroy(&thread_release_cond[s]);
+ pthread_mutex_destroy(&thread_release_mutex[s]);
}
int sensor_activate(int s, int enabled)
{
char device_name[PATH_MAX];
- char trigger_name[MAX_NAME_SIZE + 16];
- int c;
struct epoll_event ev = {0};
int dev_fd;
int ret;
int dev_num = sensor_info[s].dev_num;
- int i = sensor_info[s].catalog_index;
int is_poll_sensor = !sensor_info[s].num_channels;
+ /* If we want to activate gyro calibrated and gyro uncalibrated is activated
+ * Deactivate gyro uncalibrated - Uncalibrated releases handler
+ * Activate gyro calibrated - Calibrated has handler
+ * Reactivate gyro uncalibrated - Uncalibrated gets data from calibrated */
+
+ /* If we want to deactivate gyro calibrated and gyro uncalibrated is active
+ * Deactivate gyro uncalibrated - Uncalibrated no longer gets data from handler
+ * Deactivate gyro calibrated - Calibrated releases handler
+ * Reactivate gyro uncalibrated - Uncalibrated has handler */
+
+ if (sensor_catalog[sensor_info[s].catalog_index].type == SENSOR_TYPE_GYROSCOPE &&
+ sensor_info[s].pair_idx && sensor_info[sensor_info[s].pair_idx].enable_count != 0) {
+
+ sensor_activate(sensor_info[s].pair_idx, 0);
+ ret = sensor_activate(s, enabled);
+ sensor_activate(sensor_info[s].pair_idx, 1);
+ return ret;
+ }
+
ret = adjust_counters(s, enabled);
/* If the operation was neutral in terms of state, we're done */
if (ret <= 0)
return ret;
+
if (!is_poll_sensor) {
/* Stop sampling */
/* If there's at least one sensor enabled on this iio device */
if (trig_sensors_per_dev[dev_num]) {
- sprintf(trigger_name, "%s-dev%d",
- sensor_info[s].internal_name, dev_num);
/* Start sampling */
- setup_trigger(dev_num, trigger_name);
+ setup_trigger(dev_num, sensor_info[s].trigger_name);
enable_buffer(dev_num, 1);
}
}
unsigned char *target;
unsigned char *source;
int size;
- int ts;
+ int64_t ts;
/* There's an incoming report on the specified iio device char dev fd */
ALOGV("Read %d bytes from iio device %d\n", len, dev_num);
+ /* Map device report to sensor reports */
+
for (s=0; s<MAX_SENSORS; s++)
if (sensor_info[s].dev_num == dev_num &&
sensor_info[s].enable_count) {
sensor_info[s].report_ts = ts;
sensor_info[s].report_pending = 1;
+ sensor_info[s].report_initialized = 1;
}
return 0;
if (!num_fields)
return 0;
+
+ /* Only return uncalibrated event if also gyro active */
+ if (sensor_type == SENSOR_TYPE_GYROSCOPE_UNCALIBRATED &&
+ sensor_info[sensor_info[s].pair_idx].enable_count != 0)
+ return 0;
+
memset(data, 0, sizeof(sensors_event_t));
data->version = sizeof(sensors_event_t);
}
+static void synthetize_duplicate_samples (void)
+{
+ /*
+ * Some sensor types (ex: gyroscope) are defined as continuously firing
+ * by Android, despite the fact that we can be dealing with iio drivers
+ * that only report events for new samples. For these we generate
+ * reports periodically, duplicating the last data we got from the
+ * driver. This is not necessary for polling sensors.
+ */
+
+ int s;
+ int64_t current_ts;
+ int64_t target_ts;
+ int64_t period;
+
+ for (s=0; s<sensor_count; s++) {
+
+ /* Ignore disabled sensors */
+ if (!sensor_info[s].enable_count)
+ continue;
+
+ /* If the sensor can generate duplicates, leave it alone */
+ if (!(sensor_info[s].quirks & QUIRK_TERSE_DRIVER))
+ continue;
+
+ /* If we haven't seen a sample, there's nothing to duplicate */
+ if (!sensor_info[s].report_initialized)
+ continue;
+
+ /* If a sample was recently buffered, leave it alone too */
+ if (sensor_info[s].report_pending)
+ continue;
+
+ /* We also need a valid sampling rate to be configured */
+ if (!sensor_info[s].sampling_rate)
+ continue;
+
+ period = (int64_t) (1000000000.0/ sensor_info[s].sampling_rate);
+
+ current_ts = get_timestamp();
+ target_ts = sensor_info[s].report_ts + period;
+
+ if (target_ts <= current_ts) {
+ /* Mark the sensor for event generation */
+ sensor_info[s].report_ts = current_ts;
+ sensor_info[s].report_pending = 1;
+ }
+ }
+}
+
+
static void integrate_thread_report (uint32_t tag)
{
int s = tag - THREAD_REPORT_TAG_BASE;
}
+static int get_poll_wait_timeout (void)
+{
+ /*
+ * Compute an appropriate timeout value, in ms, for the epoll_wait
+ * call that's going to await for iio device reports and incoming
+ * reports from our sensor sysfs data reader threads.
+ */
+
+ int s;
+ int64_t target_ts = INT64_MAX;
+ int64_t ms_to_wait;
+ int64_t period;
+
+ /*
+ * Check if have have to deal with "terse" drivers that only send events
+ * when there is motion, despite the fact that the associated Android
+ * sensor type is continuous rather than on-change. In that case we have
+ * to duplicate events. Check deadline for the nearest upcoming event.
+ */
+ for (s=0; s<sensor_count; s++)
+ if (sensor_info[s].enable_count &&
+ (sensor_info[s].quirks & QUIRK_TERSE_DRIVER) &&
+ sensor_info[s].sampling_rate) {
+ period = (int64_t) (1000000000.0 /
+ sensor_info[s].sampling_rate);
+
+ if (sensor_info[s].report_ts + period < target_ts)
+ target_ts = sensor_info[s].report_ts + period;
+ }
+
+ /* If we don't have such a driver to deal with */
+ if (target_ts == INT64_MAX)
+ return -1; /* Infinite wait */
+
+ ms_to_wait = (target_ts - get_timestamp()) / 1000000;
+
+ /*
+ * If the target timestamp is very close or already behind us, wait
+ * nonetheless for a millisecond in order to a) avoid busy loops, and
+ * b) give a chance for the driver to report data before we repeat the
+ * last received sample.
+ */
+ if (ms_to_wait <= 0)
+ return 1;
+
+ return ms_to_wait;
+}
+
+
int sensor_poll(struct sensors_event_t* data, int count)
{
int s;
int i;
int nfds;
struct epoll_event ev[MAX_DEVICES];
- int64_t target_ts;
int returned_events;
+ int event_count;
/* Get one or more events from our collection of sensors */
returned_events = 0;
/* Check our sensor collection for available reports */
- for (s=0; s<sensor_count && returned_events<count; s++)
+ for (s=0; s<sensor_count && returned_events < count; s++)
if (sensor_info[s].report_pending) {
-
+ event_count = 0;
/* Lower flag */
sensor_info[s].report_pending = 0;
/* Report this event if it looks OK */
- returned_events +=
- propagate_sensor_report(s, &data[returned_events]);
-
+ event_count = propagate_sensor_report(s, &data[returned_events]);
+
+ /* Duplicate only if both cal & uncal are active */
+ if (sensor_catalog[sensor_info[s].catalog_index].type == SENSOR_TYPE_GYROSCOPE &&
+ sensor_info[s].pair_idx && sensor_info[sensor_info[s].pair_idx].enable_count != 0) {
+ struct gyro_cal* gyro_data = (struct gyro_cal*) sensor_info[s].cal_data;
+
+ memcpy(&data[returned_events + event_count], &data[returned_events],
+ sizeof(struct sensors_event_t) * event_count);
+ for (i = 0; i < event_count; i++) {
+ data[returned_events + i].type = SENSOR_TYPE_GYROSCOPE_UNCALIBRATED;
+ data[returned_events + i].sensor = sensor_info[s].pair_idx;
+
+ data[returned_events + i].data[0] = data[returned_events + i].data[0] + gyro_data->bias[0];
+ data[returned_events + i].data[1] = data[returned_events + i].data[1] + gyro_data->bias[1];
+ data[returned_events + i].data[2] = data[returned_events + i].data[2] + gyro_data->bias[2];
+
+ data[returned_events + i].uncalibrated_gyro.bias[0] = gyro_data->bias[0];
+ data[returned_events + i].uncalibrated_gyro.bias[1] = gyro_data->bias[1];
+ data[returned_events + i].uncalibrated_gyro.bias[2] = gyro_data->bias[2];
+ }
+ event_count <<= 1;
+ }
+ sensor_info[sensor_info[s].pair_idx].report_pending = 0;
+ returned_events += event_count;
/*
* If the sample was deemed invalid or unreportable,
* e.g. had the same value as the previously reported
ALOGV("Awaiting sensor data\n");
- nfds = epoll_wait(poll_fd, ev, MAX_DEVICES, -1);
+ nfds = epoll_wait(poll_fd, ev, MAX_DEVICES, get_poll_wait_timeout());
if (nfds == -1) {
- ALOGI("epoll_wait returned -1 (%s)\n", strerror(errno));
+ ALOGE("epoll_wait returned -1 (%s)\n", strerror(errno));
goto await_event;
}
+ /* Synthetize duplicate samples if needed */
+ synthetize_duplicate_samples();
+
ALOGV("%d fds signalled\n", nfds);
/* For each of the signalled sources */
/* If we're dealing with a poll-mode sensor */
if (!sensor_info[s].num_channels) {
- /* The new sampling rate will be used on next iteration */
+ /* Interrupt current sleep so the new sampling gets used */
+ pthread_cond_signal(&thread_release_cond[s]);
return 0;
}
int allocate_control_data (void)
{
int i;
- struct epoll_event ev = {0};
for (i=0; i<MAX_DEVICES; i++)
device_fd[i] = -1;