2 * Copyright (C) 2014 Intel Corporation.
10 #include <sys/epoll.h>
11 #include <sys/socket.h>
12 #include <utils/Log.h>
13 #include <hardware/sensors.h>
15 #include "enumeration.h"
17 #include "transform.h"
18 #include "calibration.h"
19 #include "description.h"
20 #include "filtering.h"
22 /* Currently active sensors count, per device */
23 static int poll_sensors_per_dev[MAX_DEVICES]; /* poll-mode sensors */
24 static int trig_sensors_per_dev[MAX_DEVICES]; /* trigger, event based */
26 static int device_fd[MAX_DEVICES]; /* fd on the /dev/iio:deviceX file */
27 static int has_iio_ts[MAX_DEVICES]; /* ts channel available on this iio dev */
28 static int expected_dev_report_size[MAX_DEVICES]; /* expected iio scan len */
29 static int poll_fd; /* epoll instance covering all enabled sensors */
31 static int active_poll_sensors; /* Number of enabled poll-mode sensors */
33 int64_t ts_delta; /* delta between SystemClock.getNanos and our timestamp */
35 static int64_t sys_to_rt_delta; /* delta between system and realtime clocks */
37 /* We use pthread condition variables to get worker threads out of sleep */
38 static pthread_condattr_t thread_cond_attr [MAX_SENSORS];
39 static pthread_cond_t thread_release_cond [MAX_SENSORS];
40 static pthread_mutex_t thread_release_mutex [MAX_SENSORS];
43 * We associate tags to each of our poll set entries. These tags have the
45 * - a iio device number if the fd is a iio character device fd
46 * - THREAD_REPORT_TAG_BASE + sensor handle if the fd is the receiving end of a
47 * pipe used by a sysfs data acquisition thread
49 #define THREAD_REPORT_TAG_BASE 0x00010000
51 #define ENABLE_BUFFER_RETRIES 10
52 #define ENABLE_BUFFER_RETRY_DELAY_MS 10
54 static int enable_buffer(int dev_num, int enabled)
56 char sysfs_path[PATH_MAX];
57 int ret, retries, millisec;
58 struct timespec req = {0};
60 retries = ENABLE_BUFFER_RETRIES;
61 millisec = ENABLE_BUFFER_RETRY_DELAY_MS;
63 req.tv_nsec = millisec * 1000000L;
65 sprintf(sysfs_path, ENABLE_PATH, dev_num);
68 /* Low level, non-multiplexed, enable/disable routine */
69 ret = sysfs_write_int(sysfs_path, enabled);
73 ALOGE("Failed enabling buffer, retrying");
74 nanosleep(&req, (struct timespec *)NULL);
78 ALOGE("Could not enable buffer\n");
86 static int setup_trigger (int s, const char* trigger_val)
88 char sysfs_path[PATH_MAX];
89 int ret = -1, attempts = 5;
91 sprintf(sysfs_path, TRIGGER_PATH, sensor_info[s].dev_num);
93 if (trigger_val[0] != '\n')
94 ALOGI("Setting S%d (%s) trigger to %s\n", s,
95 sensor_info[s].friendly_name, trigger_val);
97 while (ret == -1 && attempts) {
98 ret = sysfs_write_str(sysfs_path, trigger_val);
103 sensor_info[s].selected_trigger = trigger_val;
105 ALOGE("Setting S%d (%s) trigger to %s FAILED.\n", s,
106 sensor_info[s].friendly_name, trigger_val);
111 static void enable_iio_timestamp (int dev_num, int known_channels)
113 /* Check if we have a dedicated iio timestamp channel */
115 char spec_buf[MAX_TYPE_SPEC_LEN];
116 char sysfs_path[PATH_MAX];
119 sprintf(sysfs_path, CHANNEL_PATH "%s", dev_num, "in_timestamp_type");
121 n = sysfs_read_str(sysfs_path, spec_buf, sizeof(spec_buf));
126 if (strcmp(spec_buf, "le:s64/64>>0"))
129 /* OK, type is int64_t as expected, in little endian representation */
131 sprintf(sysfs_path, CHANNEL_PATH"%s", dev_num, "in_timestamp_index");
133 if (sysfs_read_int(sysfs_path, &n))
136 /* Check that the timestamp comes after the other fields we read */
137 if (n != known_channels)
140 /* Try enabling that channel */
141 sprintf(sysfs_path, CHANNEL_PATH "%s", dev_num, "in_timestamp_en");
143 sysfs_write_int(sysfs_path, 1);
145 if (sysfs_read_int(sysfs_path, &n))
149 ALOGI("Detected timestamp channel on iio device %d\n", dev_num);
150 has_iio_ts[dev_num] = 1;
155 void build_sensor_report_maps (int dev_num)
158 * Read sysfs files from a iio device's scan_element directory, and
159 * build a couple of tables from that data. These tables will tell, for
160 * each sensor, where to gather relevant data in a device report, i.e.
161 * the structure that we read from the /dev/iio:deviceX file in order to
162 * sensor report, itself being the data that we return to Android when a
163 * sensor poll completes. The mapping should be straightforward in the
164 * case where we have a single sensor active per iio device but, this is
165 * not the general case. In general several sensors can be handled
166 * through a single iio device, and the _en, _index and _type syfs
167 * entries all concur to paint a picture of what the structure of the
177 char spec_buf[MAX_TYPE_SPEC_LEN];
178 struct datum_info_t* ch_info;
180 char sysfs_path[PATH_MAX];
183 int channel_size_from_index[MAX_SENSORS * MAX_CHANNELS] = { 0 };
184 int sensor_handle_from_index[MAX_SENSORS * MAX_CHANNELS] = { 0 };
185 int channel_number_from_index[MAX_SENSORS * MAX_CHANNELS] = { 0 };
189 /* For each sensor that is linked to this device */
190 for (s=0; s<sensor_count; s++) {
191 if (sensor_info[s].dev_num != dev_num)
194 i = sensor_info[s].catalog_index;
196 /* Read channel details through sysfs attributes */
197 for (c=0; c<sensor_info[s].num_channels; c++) {
199 /* Read _type file */
200 sprintf(sysfs_path, CHANNEL_PATH "%s",
201 sensor_info[s].dev_num,
202 sensor_catalog[i].channel[c].type_path);
204 n = sysfs_read_str(sysfs_path, spec_buf,
208 ALOGW( "Failed to read type: %s\n",
213 ch_spec = sensor_info[s].channel[c].type_spec;
215 memcpy(ch_spec, spec_buf, sizeof(spec_buf));
217 ch_info = &sensor_info[s].channel[c].type_info;
219 size = decode_type_spec(ch_spec, ch_info);
221 /* Read _index file */
222 sprintf(sysfs_path, CHANNEL_PATH "%s",
223 sensor_info[s].dev_num,
224 sensor_catalog[i].channel[c].index_path);
226 n = sysfs_read_int(sysfs_path, &ch_index);
229 ALOGW( "Failed to read index: %s\n",
234 if (ch_index >= MAX_SENSORS) {
235 ALOGE("Index out of bounds!: %s\n", sysfs_path);
239 /* Record what this index is about */
241 sensor_handle_from_index [ch_index] = s;
242 channel_number_from_index[ch_index] = c;
243 channel_size_from_index [ch_index] = size;
248 /* Stop sampling - if we are recovering from hal restart */
249 enable_buffer(dev_num, 0);
250 setup_trigger(s, "\n");
252 /* Turn on channels we're aware of */
253 for (c=0;c<sensor_info[s].num_channels; c++) {
254 sprintf(sysfs_path, CHANNEL_PATH "%s",
255 sensor_info[s].dev_num,
256 sensor_catalog[i].channel[c].en_path);
257 sysfs_write_int(sysfs_path, 1);
261 ALOGI("Found %d channels on iio device %d\n", known_channels, dev_num);
264 * Now that we know which channels are defined, their sizes and their
265 * ordering, update channels offsets within device report. Note: there
266 * is a possibility that several sensors share the same index, with
267 * their data fields being isolated by masking and shifting as specified
268 * through the real bits and shift values in type attributes. This case
269 * is not currently supported. Also, the code below assumes no hole in
270 * the sequence of indices, so it is dependent on discovery of all
274 for (i=0; i<MAX_SENSORS * MAX_CHANNELS; i++) {
275 s = sensor_handle_from_index[i];
276 c = channel_number_from_index[i];
277 size = channel_size_from_index[i];
282 ALOGI("S%d C%d : offset %d, size %d, type %s\n",
283 s, c, offset, size, sensor_info[s].channel[c].type_spec);
285 sensor_info[s].channel[c].offset = offset;
286 sensor_info[s].channel[c].size = size;
291 /* Enable the timestamp channel if there is one available */
292 enable_iio_timestamp(dev_num, known_channels);
294 /* Add padding and timestamp size if it's enabled on this iio device */
295 if (has_iio_ts[dev_num])
296 offset = (offset+7)/8*8 + sizeof(int64_t);
298 expected_dev_report_size[dev_num] = offset;
299 ALOGI("Expecting %d scan length on iio dev %d\n", offset, dev_num);
301 if (expected_dev_report_size[dev_num] > MAX_DEVICE_REPORT_SIZE) {
302 ALOGE("Unexpectedly large scan buffer on iio dev%d: %d bytes\n",
303 dev_num, expected_dev_report_size[dev_num]);
305 expected_dev_report_size[dev_num] = MAX_DEVICE_REPORT_SIZE;
310 int adjust_counters (int s, int enabled)
313 * Adjust counters based on sensor enable action. Return values are:
314 * -1 if there's an inconsistency: abort action in this case
315 * 0 if the operation was completed and we're all set
316 * 1 if we toggled the state of the sensor and there's work left
319 int dev_num = sensor_info[s].dev_num;
321 /* Refcount per sensor, in terms of enable count */
323 ALOGI("Enabling sensor %d (iio device %d: %s)\n",
324 s, dev_num, sensor_info[s].friendly_name);
326 if (sensor_info[s].enabled)
327 return 0; /* The sensor was, and remains, in use */
329 sensor_info[s].enabled = 1;
331 switch (sensor_info[s].type) {
332 case SENSOR_TYPE_MAGNETIC_FIELD:
333 compass_read_data(&sensor_info[s]);
336 case SENSOR_TYPE_GYROSCOPE:
337 case SENSOR_TYPE_GYROSCOPE_UNCALIBRATED:
338 gyro_cal_init(&sensor_info[s]);
342 if (sensor_info[s].enabled == 0)
343 return 0; /* Spurious disable call */
345 ALOGI("Disabling sensor %d (iio device %d: %s)\n", s, dev_num,
346 sensor_info[s].friendly_name);
348 sensor_info[s].enabled = 0;
350 /* Sensor disabled, lower report available flag */
351 sensor_info[s].report_pending = 0;
353 if (sensor_info[s].type == SENSOR_TYPE_MAGNETIC_FIELD)
354 compass_store_data(&sensor_info[s]);
356 if(sensor_info[s].type == SENSOR_TYPE_GYROSCOPE ||
357 sensor_info[s].type == SENSOR_TYPE_GYROSCOPE_UNCALIBRATED)
358 gyro_store_data(&sensor_info[s]);
362 /* If uncalibrated type and pair is already active don't adjust counters */
363 if (sensor_info[s].type == SENSOR_TYPE_GYROSCOPE_UNCALIBRATED &&
364 sensor_info[sensor_info[s].pair_idx].enabled != 0)
367 /* We changed the state of a sensor - adjust per iio device counters */
369 /* If this is a regular event-driven sensor */
370 if (sensor_info[s].num_channels) {
373 trig_sensors_per_dev[dev_num]++;
375 trig_sensors_per_dev[dev_num]--;
381 active_poll_sensors++;
382 poll_sensors_per_dev[dev_num]++;
386 active_poll_sensors--;
387 poll_sensors_per_dev[dev_num]--;
392 static int get_field_count (int s)
394 switch (sensor_info[s].type) {
395 case SENSOR_TYPE_ACCELEROMETER: /* m/s^2 */
396 case SENSOR_TYPE_MAGNETIC_FIELD: /* micro-tesla */
397 case SENSOR_TYPE_ORIENTATION: /* degrees */
398 case SENSOR_TYPE_GYROSCOPE_UNCALIBRATED:
399 case SENSOR_TYPE_GYROSCOPE: /* radians/s */
402 case SENSOR_TYPE_LIGHT: /* SI lux units */
403 case SENSOR_TYPE_AMBIENT_TEMPERATURE: /* °C */
404 case SENSOR_TYPE_TEMPERATURE: /* °C */
405 case SENSOR_TYPE_PROXIMITY: /* centimeters */
406 case SENSOR_TYPE_PRESSURE: /* hecto-pascal */
407 case SENSOR_TYPE_RELATIVE_HUMIDITY: /* percent */
410 case SENSOR_TYPE_ROTATION_VECTOR:
414 ALOGE("Unknown sensor type!\n");
415 return 0; /* Drop sample */
420 static void* acquisition_routine (void* param)
423 * Data acquisition routine run in a dedicated thread, covering a single
424 * sensor. This loop will periodically retrieve sampling data through
425 * sysfs, then package it as a sample and transfer it to our master poll
426 * loop through a report fd. Checks for a cancellation signal quite
427 * frequently, as the thread may be disposed of at any time. Note that
428 * Bionic does not provide pthread_cancel / pthread_testcancel...
431 int s = (int) (size_t) param;
432 int num_fields, sample_size;
433 struct sensors_event_t data = {0};
436 struct timespec target_time;
437 int64_t timestamp, period, start, stop;
439 if (s < 0 || s >= sensor_count) {
440 ALOGE("Invalid sensor handle!\n");
444 ALOGI("Entering data acquisition thread S%d (%s): rate(%f), ts(%lld)\n", s,
445 sensor_info[s].friendly_name, sensor_info[s].sampling_rate, sensor_info[s].report_ts);
447 if (sensor_info[s].sampling_rate <= 0) {
448 ALOGE("Non-positive rate in acquisition routine for sensor %d: %f\n",
449 s, sensor_info[s].sampling_rate);
453 num_fields = get_field_count(s);
454 sample_size = sizeof(int64_t) + num_fields * sizeof(float);
457 * Each condition variable is associated to a mutex that has to be
458 * locked by the thread that's waiting on it. We use these condition
459 * variables to get the acquisition threads out of sleep quickly after
460 * the sampling rate is adjusted, or the sensor is disabled.
462 pthread_mutex_lock(&thread_release_mutex[s]);
464 /* Pinpoint the moment we start sampling */
465 timestamp = get_timestamp_monotonic();
467 /* Check and honor termination requests */
468 while (sensor_info[s].thread_data_fd[1] != -1) {
469 start = get_timestamp();
470 /* Read values through sysfs */
471 for (c=0; c<num_fields; c++) {
472 data.data[c] = acquire_immediate_value(s, c);
473 /* Check and honor termination requests */
474 if (sensor_info[s].thread_data_fd[1] == -1)
477 stop = get_timestamp();
478 data.timestamp = start/2 + stop/2;
480 /* If the sample looks good */
481 if (sensor_info[s].ops.finalize(s, &data)) {
483 /* Pipe it for transmission to poll loop */
484 ret = write( sensor_info[s].thread_data_fd[1],
485 &data.timestamp, sample_size);
487 if (ret != sample_size)
488 ALOGE("S%d acquisition thread: tried to write %d, ret: %d\n",
489 s, sample_size, ret);
492 /* Check and honor termination requests */
493 if (sensor_info[s].thread_data_fd[1] == -1)
496 /* Recalculate period asumming sensor_info[s].sampling_rate
497 * can be changed dynamically during the thread run */
498 if (sensor_info[s].sampling_rate <= 0) {
499 ALOGE("Non-positive rate in acquisition routine for sensor %d: %f\n",
500 s, sensor_info[s].sampling_rate);
504 period = (int64_t) (1000000000LL / sensor_info[s].sampling_rate);
506 set_timestamp(&target_time, timestamp);
509 * Wait until the sampling time elapses, or a rate change is
510 * signaled, or a thread exit is requested.
512 ret = pthread_cond_timedwait( &thread_release_cond[s],
513 &thread_release_mutex[s],
518 ALOGV("Acquisition thread for S%d exiting\n", s);
519 pthread_mutex_unlock(&thread_release_mutex[s]);
525 static void start_acquisition_thread (int s)
527 int incoming_data_fd;
530 struct epoll_event ev = {0};
532 ALOGV("Initializing acquisition context for sensor %d\n", s);
534 /* Create condition variable and mutex for quick thread release */
535 ret = pthread_condattr_init(&thread_cond_attr[s]);
536 ret = pthread_condattr_setclock(&thread_cond_attr[s], CLOCK_MONOTONIC);
537 ret = pthread_cond_init(&thread_release_cond[s], &thread_cond_attr[s]);
538 ret = pthread_mutex_init(&thread_release_mutex[s], NULL);
540 /* Create a pipe for inter thread communication */
541 ret = pipe(sensor_info[s].thread_data_fd);
543 incoming_data_fd = sensor_info[s].thread_data_fd[0];
546 ev.data.u32 = THREAD_REPORT_TAG_BASE + s;
548 /* Add incoming side of pipe to our poll set, with a suitable tag */
549 ret = epoll_ctl(poll_fd, EPOLL_CTL_ADD, incoming_data_fd , &ev);
551 /* Create and start worker thread */
552 ret = pthread_create( &sensor_info[s].acquisition_thread,
559 static void stop_acquisition_thread (int s)
561 int incoming_data_fd = sensor_info[s].thread_data_fd[0];
562 int outgoing_data_fd = sensor_info[s].thread_data_fd[1];
564 ALOGV("Tearing down acquisition context for sensor %d\n", s);
566 /* Delete the incoming side of the pipe from our poll set */
567 epoll_ctl(poll_fd, EPOLL_CTL_DEL, incoming_data_fd, NULL);
569 /* Mark the pipe ends as invalid ; that's a cheap exit flag */
570 sensor_info[s].thread_data_fd[0] = -1;
571 sensor_info[s].thread_data_fd[1] = -1;
573 /* Close both sides of our pipe */
574 close(incoming_data_fd);
575 close(outgoing_data_fd);
577 /* Stop acquisition thread and clean up thread handle */
578 pthread_cond_signal(&thread_release_cond[s]);
579 pthread_join(sensor_info[s].acquisition_thread, NULL);
581 /* Clean up our sensor descriptor */
582 sensor_info[s].acquisition_thread = -1;
584 /* Delete condition variable and mutex */
585 pthread_cond_destroy(&thread_release_cond[s]);
586 pthread_mutex_destroy(&thread_release_mutex[s]);
590 int sensor_activate(int s, int enabled)
592 char device_name[PATH_MAX];
593 struct epoll_event ev = {0};
596 int dev_num = sensor_info[s].dev_num;
597 int is_poll_sensor = !sensor_info[s].num_channels;
599 /* Prepare the report timestamp field for the first event, see set_report_ts method */
600 sensor_info[s].report_ts = 0;
601 ts_delta = load_timestamp_sys_clock() - get_timestamp_monotonic();
602 sys_to_rt_delta = get_timestamp_realtime - load_timestamp_sys_clock();
605 /* If we want to activate gyro calibrated and gyro uncalibrated is activated
606 * Deactivate gyro uncalibrated - Uncalibrated releases handler
607 * Activate gyro calibrated - Calibrated has handler
608 * Reactivate gyro uncalibrated - Uncalibrated gets data from calibrated */
610 /* If we want to deactivate gyro calibrated and gyro uncalibrated is active
611 * Deactivate gyro uncalibrated - Uncalibrated no longer gets data from handler
612 * Deactivate gyro calibrated - Calibrated releases handler
613 * Reactivate gyro uncalibrated - Uncalibrated has handler */
615 if (sensor_info[s].type == SENSOR_TYPE_GYROSCOPE &&
616 sensor_info[s].pair_idx && sensor_info[sensor_info[s].pair_idx].enabled != 0) {
618 sensor_activate(sensor_info[s].pair_idx, 0);
619 ret = sensor_activate(s, enabled);
620 sensor_activate(sensor_info[s].pair_idx, 1);
624 ret = adjust_counters(s, enabled);
626 /* If the operation was neutral in terms of state, we're done */
630 sensor_info[s].event_count = 0;
631 sensor_info[s].meta_data_pending = 0;
633 if (enabled && (sensor_info[s].quirks & QUIRK_NOISY))
634 /* Initialize filtering data if required */
635 setup_noise_filtering(s);
637 if (!is_poll_sensor) {
640 enable_buffer(dev_num, 0);
641 setup_trigger(s, "\n");
643 /* If there's at least one sensor enabled on this iio device */
644 if (trig_sensors_per_dev[dev_num]) {
647 setup_trigger(s, sensor_info[s].init_trigger_name);
648 enable_buffer(dev_num, 1);
653 * Make sure we have a fd on the character device ; conversely, close
654 * the fd if no one is using associated sensors anymore. The assumption
655 * here is that the underlying driver will power on the relevant
656 * hardware block while someone holds a fd on the device.
658 dev_fd = device_fd[dev_num];
662 stop_acquisition_thread(s);
664 if (dev_fd != -1 && !poll_sensors_per_dev[dev_num] &&
665 !trig_sensors_per_dev[dev_num]) {
667 * Stop watching this fd. This should be a no-op
668 * in case this fd was not in the poll set.
670 epoll_ctl(poll_fd, EPOLL_CTL_DEL, dev_fd, NULL);
673 device_fd[dev_num] = -1;
676 /* Release any filtering data we may have accumulated */
677 release_noise_filtering_data(s);
683 /* First enabled sensor on this iio device */
684 sprintf(device_name, DEV_FILE_PATH, dev_num);
685 dev_fd = open(device_name, O_RDONLY | O_NONBLOCK);
687 device_fd[dev_num] = dev_fd;
690 ALOGE("Could not open fd on %s (%s)\n",
691 device_name, strerror(errno));
692 adjust_counters(s, 0);
696 ALOGV("Opened %s: fd=%d\n", device_name, dev_fd);
698 if (!is_poll_sensor) {
700 /* Add this iio device fd to the set of watched fds */
702 ev.data.u32 = dev_num;
704 ret = epoll_ctl(poll_fd, EPOLL_CTL_ADD, dev_fd, &ev);
707 ALOGE( "Failed adding %d to poll set (%s)\n",
708 dev_fd, strerror(errno));
712 /* Note: poll-mode fds are not readable */
716 /* Ensure that on-change sensors send at least one event after enable */
717 sensor_info[s].prev_val = -1;
720 start_acquisition_thread(s);
726 static int is_fast_accelerometer (int s)
729 * Some games don't react well to accelerometers using any-motion
730 * triggers. Even very low thresholds seem to trip them, and they tend
731 * to request fairly high event rates. Favor continuous triggers if the
732 * sensor is an accelerometer and uses a sampling rate of at least 25.
735 if (sensor_info[s].type != SENSOR_TYPE_ACCELEROMETER)
738 if (sensor_info[s].sampling_rate < 25)
745 static void enable_motion_trigger (int dev_num)
748 * In the ideal case, we enumerate two triggers per iio device ; the
749 * default (periodically firing) trigger, and another one (the motion
750 * trigger) that only fires up when motion is detected. This second one
751 * allows for lesser energy consumption, but requires periodic sample
752 * duplication at the HAL level for sensors that Android defines as
753 * continuous. This "duplicate last sample" logic can only be engaged
754 * once we got a first sample for the driver, so we start with the
755 * default trigger when an iio device is first opened, then adjust the
756 * trigger when we got events for all active sensors. Unfortunately in
757 * the general case several sensors can be associated to a given iio
758 * device, they can independently be controlled, and we have to adjust
759 * the trigger in use at the iio device level depending on whether or
760 * not appropriate conditions are met at the sensor level.
765 int active_sensors = trig_sensors_per_dev[dev_num];
766 int candidate[MAX_SENSORS];
767 int candidate_count = 0;
772 /* Check that all active sensors are ready to switch */
774 for (s=0; s<MAX_SENSORS; s++)
775 if (sensor_info[s].dev_num == dev_num &&
776 sensor_info[s].enabled &&
777 sensor_info[s].num_channels &&
778 (!sensor_info[s].motion_trigger_name[0] ||
779 !sensor_info[s].report_initialized ||
780 is_fast_accelerometer(s) ||
781 (sensor_info[s].quirks & QUIRK_FORCE_CONTINUOUS))
785 /* Record which particular sensors need to switch */
787 for (s=0; s<MAX_SENSORS; s++)
788 if (sensor_info[s].dev_num == dev_num &&
789 sensor_info[s].enabled &&
790 sensor_info[s].num_channels &&
791 sensor_info[s].selected_trigger !=
792 sensor_info[s].motion_trigger_name)
793 candidate[candidate_count++] = s;
795 if (!candidate_count)
798 /* Now engage the motion trigger for sensors which aren't using it */
800 enable_buffer(dev_num, 0);
802 for (i=0; i<candidate_count; i++) {
804 setup_trigger(s, sensor_info[s].motion_trigger_name);
807 enable_buffer(dev_num, 1);
810 /* CTS acceptable thresholds:
811 * EventGapVerification.java: (th <= 1.8)
812 * FrequencyVerification.java: (0.9)*(expected freq) => (th <= 1.1111)
814 #define THRESHOLD 1.10
815 #define MAX_DELAY 500000000 /* 500 ms */
816 void set_report_ts(int s, int64_t ts)
818 int64_t maxTs, period;
819 int catalog_index = sensor_info[s].catalog_index;
820 int is_accel = (sensor_catalog[catalog_index].type == SENSOR_TYPE_ACCELEROMETER);
823 * A bit of a hack to please a bunch of cts tests. They
824 * expect the timestamp to be exacly according to the set-up
825 * frequency but if we're simply getting the timestamp at hal level
826 * this may not be the case. Perhaps we'll get rid of this when
827 * we'll be reading the timestamp from the iio channel for all sensors
829 if (sensor_info[s].report_ts && sensor_info[s].sampling_rate &&
830 REPORTING_MODE(sensor_desc[s].flags) == SENSOR_FLAG_CONTINUOUS_MODE)
832 period = (int64_t) (1000000000LL / sensor_info[s].sampling_rate);
833 maxTs = sensor_info[s].report_ts + (is_accel ? 1 : THRESHOLD) * period;
834 /* If we're too far behind get back on track */
835 if (ts - maxTs >= MAX_DELAY)
837 sensor_info[s].report_ts = (ts < maxTs ? ts : maxTs);
839 sensor_info[s].report_ts = ts;
844 static int integrate_device_report (int dev_num)
848 unsigned char buf[MAX_DEVICE_REPORT_SIZE] = { 0 };
850 unsigned char *target;
851 unsigned char *source;
854 int ts_offset = 0; /* Offset of iio timestamp, if provided */
856 /* There's an incoming report on the specified iio device char dev fd */
858 if (dev_num < 0 || dev_num >= MAX_DEVICES) {
859 ALOGE("Event reported on unexpected iio device %d\n", dev_num);
863 if (device_fd[dev_num] == -1) {
864 ALOGE("Ignoring stale report on iio device %d\n", dev_num);
868 len = read(device_fd[dev_num], buf, expected_dev_report_size[dev_num]);
871 ALOGE("Could not read report from iio device %d (%s)\n",
872 dev_num, strerror(errno));
876 ALOGV("Read %d bytes from iio device %d\n", len, dev_num);
878 /* Map device report to sensor reports */
880 for (s=0; s<MAX_SENSORS; s++)
881 if (sensor_info[s].dev_num == dev_num &&
882 sensor_info[s].enabled) {
886 /* Copy data from device to sensor report buffer */
887 for (c=0; c<sensor_info[s].num_channels; c++) {
889 target = sensor_info[s].report_buffer +
892 source = buf + sensor_info[s].channel[c].offset;
894 size = sensor_info[s].channel[c].size;
896 memcpy(target, source, size);
901 ALOGV("Sensor %d report available (%d bytes)\n", s,
904 sensor_info[s].report_pending = DATA_TRIGGER;
905 sensor_info[s].report_initialized = 1;
906 set_report_ts(s, get_timestamp());
908 ts_offset += sr_offset;
911 /* Tentatively switch to an any-motion trigger if conditions are met */
912 enable_motion_trigger(dev_num);
914 /* If no iio timestamp channel was detected for this device, bail out */
915 if (!has_iio_ts[dev_num])
918 /* Align on a 64 bits boundary */
919 ts_offset = (ts_offset + 7)/8*8;
921 /* If we read an amount of data consistent with timestamp presence */
922 if (len == expected_dev_report_size[dev_num])
923 ts = *(int64_t*) (buf + ts_offset);
926 ALOGV("Unreliable timestamp channel on iio dev %d\n", dev_num);
930 ALOGV("Driver timestamp on iio device %d: ts=%lld\n", dev_num, ts);
932 for (s=0; s<MAX_SENSORS; s++)
933 if (sensor_info[s].dev_num == dev_num && sensor_info[s].enabled)
934 set_report_ts(s, ts - sys_to_rt_delta);
940 static int propagate_sensor_report (int s, struct sensors_event_t *data)
942 /* There's a sensor report pending for this sensor ; transmit it */
944 int num_fields = get_field_count(s);
946 unsigned char* current_sample;
948 /* If there's nothing to return... we're done */
953 /* Only return uncalibrated event if also gyro active */
954 if (sensor_info[s].type == SENSOR_TYPE_GYROSCOPE_UNCALIBRATED &&
955 sensor_info[sensor_info[s].pair_idx].enabled != 0)
958 memset(data, 0, sizeof(sensors_event_t));
960 data->version = sizeof(sensors_event_t);
962 data->type = sensor_info[s].type;
963 data->timestamp = sensor_info[s].report_ts;
965 ALOGV("Sample on sensor %d (type %d):\n", s, sensor_info[s].type);
967 current_sample = sensor_info[s].report_buffer;
969 /* If this is a poll sensor */
970 if (!sensor_info[s].num_channels) {
971 /* Use the data provided by the acquisition thread */
972 ALOGV("Reporting data from worker thread for S%d\n", s);
973 memcpy(data->data, current_sample, num_fields * sizeof(float));
977 /* Convert the data into the expected Android-level format */
978 for (c=0; c<num_fields; c++) {
980 data->data[c] = sensor_info[s].ops.transform
981 (s, c, current_sample);
983 ALOGV("\tfield %d: %f\n", c, data->data[c]);
984 current_sample += sensor_info[s].channel[c].size;
988 * The finalize routine, in addition to its late sample processing duty,
989 * has the final say on whether or not the sample gets sent to Android.
991 return sensor_info[s].ops.finalize(s, data);
995 static void synthetize_duplicate_samples (void)
998 * Some sensor types (ex: gyroscope) are defined as continuously firing
999 * by Android, despite the fact that we can be dealing with iio drivers
1000 * that only report events for new samples. For these we generate
1001 * reports periodically, duplicating the last data we got from the
1002 * driver. This is not necessary for polling sensors.
1010 for (s=0; s<sensor_count; s++) {
1012 /* Ignore disabled sensors */
1013 if (!sensor_info[s].enabled)
1016 /* If the sensor is continuously firing, leave it alone */
1017 if (sensor_info[s].selected_trigger !=
1018 sensor_info[s].motion_trigger_name)
1021 /* If we haven't seen a sample, there's nothing to duplicate */
1022 if (!sensor_info[s].report_initialized)
1025 /* If a sample was recently buffered, leave it alone too */
1026 if (sensor_info[s].report_pending)
1029 /* We also need a valid sampling rate to be configured */
1030 if (!sensor_info[s].sampling_rate)
1033 period = (int64_t) (1000000000.0/ sensor_info[s].sampling_rate);
1035 current_ts = get_timestamp();
1036 target_ts = sensor_info[s].report_ts + period;
1038 if (target_ts <= current_ts) {
1039 /* Mark the sensor for event generation */
1040 set_report_ts(s, current_ts);
1041 sensor_info[s].report_pending = DATA_DUPLICATE;
1047 static void integrate_thread_report (uint32_t tag)
1049 int s = tag - THREAD_REPORT_TAG_BASE;
1053 unsigned char current_sample[MAX_SENSOR_REPORT_SIZE];
1055 expected_len = sizeof(int64_t) + get_field_count(s) * sizeof(float);
1057 len = read(sensor_info[s].thread_data_fd[0],
1061 memcpy(×tamp, current_sample, sizeof(int64_t));
1062 memcpy(sensor_info[s].report_buffer, sizeof(int64_t) + current_sample,
1063 expected_len - sizeof(int64_t));
1065 if (len == expected_len) {
1066 set_report_ts(s, timestamp);
1067 sensor_info[s].report_pending = DATA_SYSFS;
1072 static int get_poll_wait_timeout (void)
1075 * Compute an appropriate timeout value, in ms, for the epoll_wait
1076 * call that's going to await for iio device reports and incoming
1077 * reports from our sensor sysfs data reader threads.
1081 int64_t target_ts = INT64_MAX;
1086 * Check if we're dealing with a driver that only send events when
1087 * there is motion, despite the fact that the associated Android sensor
1088 * type is continuous rather than on-change. In that case we have to
1089 * duplicate events. Check deadline for the nearest upcoming event.
1091 for (s=0; s<sensor_count; s++)
1092 if (sensor_info[s].enabled &&
1093 sensor_info[s].selected_trigger ==
1094 sensor_info[s].motion_trigger_name &&
1095 sensor_info[s].sampling_rate) {
1096 period = (int64_t) (1000000000.0 /
1097 sensor_info[s].sampling_rate);
1099 if (sensor_info[s].report_ts + period < target_ts)
1100 target_ts = sensor_info[s].report_ts + period;
1103 /* If we don't have such a driver to deal with */
1104 if (target_ts == INT64_MAX)
1105 return -1; /* Infinite wait */
1107 ms_to_wait = (target_ts - get_timestamp()) / 1000000;
1109 /* If the target timestamp is already behind us, don't wait */
1117 int sensor_poll(struct sensors_event_t* data, int count)
1122 struct epoll_event ev[MAX_DEVICES];
1123 int returned_events;
1127 /* Get one or more events from our collection of sensors */
1129 return_available_sensor_reports:
1131 /* Synthetize duplicate samples if needed */
1132 synthetize_duplicate_samples();
1134 returned_events = 0;
1136 /* Check our sensor collection for available reports */
1137 for (s=0; s<sensor_count && returned_events < count; s++) {
1138 if (sensor_info[s].report_pending) {
1141 /* Report this event if it looks OK */
1142 event_count = propagate_sensor_report(s, &data[returned_events]);
1145 sensor_info[s].report_pending = 0;
1147 /* Duplicate only if both cal & uncal are active */
1148 if (sensor_info[s].type == SENSOR_TYPE_GYROSCOPE &&
1149 sensor_info[s].pair_idx && sensor_info[sensor_info[s].pair_idx].enabled != 0) {
1150 struct gyro_cal* gyro_data = (struct gyro_cal*) sensor_info[s].cal_data;
1152 memcpy(&data[returned_events + event_count], &data[returned_events],
1153 sizeof(struct sensors_event_t) * event_count);
1155 uncal_start = returned_events + event_count;
1156 for (i = 0; i < event_count; i++) {
1157 data[uncal_start + i].type = SENSOR_TYPE_GYROSCOPE_UNCALIBRATED;
1158 data[uncal_start + i].sensor = sensor_info[s].pair_idx;
1160 data[uncal_start + i].data[0] = data[returned_events + i].data[0] + gyro_data->bias_x;
1161 data[uncal_start + i].data[1] = data[returned_events + i].data[1] + gyro_data->bias_y;
1162 data[uncal_start + i].data[2] = data[returned_events + i].data[2] + gyro_data->bias_z;
1164 data[uncal_start + i].uncalibrated_gyro.bias[0] = gyro_data->bias_x;
1165 data[uncal_start + i].uncalibrated_gyro.bias[1] = gyro_data->bias_y;
1166 data[uncal_start + i].uncalibrated_gyro.bias[2] = gyro_data->bias_z;
1170 sensor_info[sensor_info[s].pair_idx].report_pending = 0;
1171 returned_events += event_count;
1173 * If the sample was deemed invalid or unreportable,
1174 * e.g. had the same value as the previously reported
1175 * value for a 'on change' sensor, silently drop it.
1178 while (sensor_info[s].meta_data_pending) {
1179 /* See sensors.h on these */
1180 data[returned_events].version = META_DATA_VERSION;
1181 data[returned_events].sensor = 0;
1182 data[returned_events].type = SENSOR_TYPE_META_DATA;
1183 data[returned_events].reserved0 = 0;
1184 data[returned_events].timestamp = 0;
1185 data[returned_events].meta_data.sensor = s;
1186 data[returned_events].meta_data.what = META_DATA_FLUSH_COMPLETE;
1188 sensor_info[s].meta_data_pending--;
1191 if (returned_events)
1192 return returned_events;
1196 ALOGV("Awaiting sensor data\n");
1198 nfds = epoll_wait(poll_fd, ev, MAX_DEVICES, get_poll_wait_timeout());
1201 ALOGE("epoll_wait returned -1 (%s)\n", strerror(errno));
1205 ALOGV("%d fds signalled\n", nfds);
1207 /* For each of the signalled sources */
1208 for (i=0; i<nfds; i++)
1209 if (ev[i].events == EPOLLIN)
1210 switch (ev[i].data.u32) {
1211 case 0 ... MAX_DEVICES-1:
1212 /* Read report from iio char dev fd */
1213 integrate_device_report(ev[i].data.u32);
1216 case THREAD_REPORT_TAG_BASE ...
1217 THREAD_REPORT_TAG_BASE + MAX_SENSORS-1:
1218 /* Get report from acquisition thread */
1219 integrate_thread_report(ev[i].data.u32);
1223 ALOGW("Unexpected event source!\n");
1227 goto return_available_sensor_reports;
1231 static void tentative_switch_trigger (int s)
1234 * Under certain situations it may be beneficial to use an alternate
1237 * - for applications using the accelerometer with high sampling rates,
1238 * prefer the continuous trigger over the any-motion one, to avoid
1239 * jumps related to motion thresholds
1242 if (is_fast_accelerometer(s) &&
1243 !(sensor_info[s].quirks & QUIRK_TERSE_DRIVER) &&
1244 sensor_info[s].selected_trigger ==
1245 sensor_info[s].motion_trigger_name)
1246 setup_trigger(s, sensor_info[s].init_trigger_name);
1250 int sensor_set_delay(int s, int64_t ns)
1252 /* Set the rate at which a specific sensor should report events */
1254 /* See Android sensors.h for indication on sensor trigger modes */
1256 char sysfs_path[PATH_MAX];
1257 char avail_sysfs_path[PATH_MAX];
1258 int dev_num = sensor_info[s].dev_num;
1259 int i = sensor_info[s].catalog_index;
1260 const char *prefix = sensor_catalog[i].tag;
1261 float new_sampling_rate; /* Granted sampling rate after arbitration */
1262 float cur_sampling_rate; /* Currently used sampling rate */
1263 int per_sensor_sampling_rate;
1264 int per_device_sampling_rate;
1265 int32_t min_delay_us = sensor_desc[s].minDelay;
1266 max_delay_t max_delay_us = sensor_desc[s].maxDelay;
1267 float min_supported_rate = max_delay_us ? (1000000.0 / max_delay_us) : 1;
1268 float max_supported_rate =
1269 (min_delay_us && min_delay_us != -1) ? (1000000.0 / min_delay_us) : 0;
1270 char freqs_buf[100];
1276 ALOGE("Rejecting non-positive delay request on sensor %d, required delay: %lld\n", s, ns);
1280 new_sampling_rate = 1000000000LL/ns;
1282 ALOGV("Entering set delay S%d (%s): old rate(%f), new rate(%f)\n",
1283 s, sensor_info[s].friendly_name, sensor_info[s].sampling_rate,
1287 * Artificially limit ourselves to 1 Hz or higher. This is mostly to
1288 * avoid setting up the stage for divisions by zero.
1290 if (new_sampling_rate < min_supported_rate)
1291 new_sampling_rate = min_supported_rate;
1293 if (max_supported_rate &&
1294 new_sampling_rate > max_supported_rate) {
1295 new_sampling_rate = max_supported_rate;
1298 sensor_info[s].sampling_rate = new_sampling_rate;
1300 /* If we're dealing with a poll-mode sensor */
1301 if (!sensor_info[s].num_channels) {
1302 /* Interrupt current sleep so the new sampling gets used */
1303 pthread_cond_signal(&thread_release_cond[s]);
1307 sprintf(sysfs_path, SENSOR_SAMPLING_PATH, dev_num, prefix);
1309 if (sysfs_read_float(sysfs_path, &cur_sampling_rate) != -1) {
1310 per_sensor_sampling_rate = 1;
1311 per_device_sampling_rate = 0;
1313 per_sensor_sampling_rate = 0;
1315 sprintf(sysfs_path, DEVICE_SAMPLING_PATH, dev_num);
1317 if (sysfs_read_float(sysfs_path, &cur_sampling_rate) != -1)
1318 per_device_sampling_rate = 1;
1320 per_device_sampling_rate = 0;
1323 if (!per_sensor_sampling_rate && !per_device_sampling_rate) {
1324 ALOGE("No way to adjust sampling rate on sensor %d\n", s);
1328 /* Coordinate with others active sensors on the same device, if any */
1329 if (per_device_sampling_rate)
1330 for (n=0; n<sensor_count; n++)
1331 if (n != s && sensor_info[n].dev_num == dev_num &&
1332 sensor_info[n].num_channels &&
1333 sensor_info[n].enabled &&
1334 sensor_info[n].sampling_rate > new_sampling_rate)
1335 new_sampling_rate= sensor_info[n].sampling_rate;
1337 /* Check if we have contraints on allowed sampling rates */
1339 sprintf(avail_sysfs_path, DEVICE_AVAIL_FREQ_PATH, dev_num);
1341 if (sysfs_read_str(avail_sysfs_path, freqs_buf, sizeof(freqs_buf)) > 0){
1344 /* Decode allowed sampling rates string, ex: "10 20 50 100" */
1346 /* While we're not at the end of the string */
1347 while (*cursor && cursor[0]) {
1349 /* Decode a single value */
1350 sr = strtod(cursor, NULL);
1352 /* If this matches the selected rate, we're happy */
1353 if (new_sampling_rate == sr)
1357 * If we reached a higher value than the desired rate,
1358 * adjust selected rate so it matches the first higher
1359 * available one and stop parsing - this makes the
1360 * assumption that rates are sorted by increasing value
1361 * in the allowed frequencies string.
1363 if (sr > new_sampling_rate) {
1364 new_sampling_rate = sr;
1369 while (cursor[0] && !isspace(cursor[0]))
1373 while (cursor[0] && isspace(cursor[0]))
1378 if (max_supported_rate &&
1379 new_sampling_rate > max_supported_rate) {
1380 new_sampling_rate = max_supported_rate;
1383 /* If the desired rate is already active we're all set */
1384 if (new_sampling_rate == cur_sampling_rate)
1387 ALOGI("Sensor %d sampling rate set to %g\n", s, new_sampling_rate);
1389 if (trig_sensors_per_dev[dev_num])
1390 enable_buffer(dev_num, 0);
1392 sysfs_write_float(sysfs_path, new_sampling_rate);
1394 /* Check if it makes sense to use an alternate trigger */
1395 tentative_switch_trigger(s);
1397 if (trig_sensors_per_dev[dev_num])
1398 enable_buffer(dev_num, 1);
1403 int sensor_flush (int s)
1405 /* If one shot or not enabled return -EINVAL */
1406 if (sensor_desc[s].flags & SENSOR_FLAG_ONE_SHOT_MODE ||
1407 sensor_info[s].enabled == 0)
1410 sensor_info[s].meta_data_pending++;
1414 int allocate_control_data (void)
1418 for (i=0; i<MAX_DEVICES; i++)
1421 poll_fd = epoll_create(MAX_DEVICES);
1423 if (poll_fd == -1) {
1424 ALOGE("Can't create epoll instance for iio sensors!\n");
1432 void delete_control_data (void)