Merge "Only requantize sensor max range if significant" into sc-dev (252a8c5e) · Commits · e / os / android_frameworks_native

services/sensorservice/SensorDevice.cpp

+17 −13

Original line number	Diff line number	Diff line
		@@ -132,8 +132,6 @@ SensorDevice::SensorDevice()
		}

		void SensorDevice::initializeSensorList() {
		float minPowerMa = 0.001; // 1 microAmp

		checkReturn(mSensors->getSensorsList(
		[&](const auto &list) {
		const size_t count = list.size();
		@@ -151,13 +149,18 @@ void SensorDevice::initializeSensorList() {
		// Don't crash in this case since CTS will verify that devices don't go to
		// production with a resolution of 0.
		if (sensor.resolution != 0) {
		double promotedResolution = sensor.resolution;
		double promotedMaxRange = sensor.maxRange;
		if (fmod(promotedMaxRange, promotedResolution) != 0) {
		ALOGW("%s's max range %f is not a multiple of the resolution %f",
		sensor.name, sensor.maxRange, sensor.resolution);
		float quantizedRange = sensor.maxRange;
		SensorDeviceUtils::quantizeValue(
		&sensor.maxRange, promotedResolution);
		&quantizedRange, sensor.resolution, /factor=/ 1);
		// Only rewrite maxRange if the requantization produced a "significant"
		// change, which is fairly arbitrarily defined as resolution / 8.
		// Smaller deltas are permitted, as they may simply be due to floating
		// point representation error, etc.
		if (fabsf(sensor.maxRange - quantizedRange) > sensor.resolution / 8) {
		ALOGW("%s's max range %.12f is not a multiple of the resolution "
		"%.12f - updated to %.12f", sensor.name, sensor.maxRange,
		sensor.resolution, quantizedRange);
		sensor.maxRange = quantizedRange;
		}
		} else {
		// Don't crash here or the device will go into a crashloop.
		@@ -166,10 +169,11 @@ void SensorDevice::initializeSensorList() {
		}

		// Sanity check and clamp power if it is 0 (or close)
		if (sensor.power < minPowerMa) {
		ALOGI("Reported power %f not deemed sane, clamping to %f",
		sensor.power, minPowerMa);
		sensor.power = minPowerMa;
		constexpr float MIN_POWER_MA = 0.001; // 1 microAmp
		if (sensor.power < MIN_POWER_MA) {
		ALOGI("%s's reported power %f invalid, clamped to %f",
		sensor.name, sensor.power, MIN_POWER_MA);
		sensor.power = MIN_POWER_MA;
		}
		mSensorList.push_back(sensor);

services/sensorservice/SensorDeviceUtils.h

+5 −6

Original line number	Diff line number	Diff line
		@@ -32,16 +32,15 @@ using ::android::hidl::manager::V1_0::IServiceNotification;
		namespace android {
		namespace SensorDeviceUtils {

		// Quantizes a single value using a sensor's resolution.
		inline void quantizeValue(float *value, double resolution) {
		// Quantizes a single value to (a fractional factor of) a sensor's resolution. Typically we
		// increase the value of the sensor's nominal resolution to ensure that sensor accuracy
		// improvements, like runtime calibration, are not masked during requantization.
		inline void quantizeValue(float *value, double resolution, double factor = 0.125) {
		if (resolution == 0) {
		return;
		}

		// Increase the value of the sensor's nominal resolution to ensure that
		// sensor accuracy improvements, like runtime calibration, are not masked
		// during requantization.
		double incRes = 0.125 * resolution;
		double incRes = factor * resolution;
		value = round(static_cast<double>(value) / incRes) * incRes;
		}