Camera: new buffer management HIDL APIs
No actual implementations yet.
Test: compile, new VTS to be written
Bug: 109829698
Change-Id: Ibe509dd743a84b147fdfed6599d8f066adb8793b
diff --git a/camera/device/3.2/ICameraDevice.hal b/camera/device/3.2/ICameraDevice.hal
index 1f523e4..5236bb1 100644
--- a/camera/device/3.2/ICameraDevice.hal
+++ b/camera/device/3.2/ICameraDevice.hal
@@ -148,7 +148,9 @@
* session handle for active operations.
*
* @param callback Interface to invoke by the HAL for device asynchronous
- * events.
+ * events. For HALs newer than version 3.2, HAL must use castFrom
+ * method to check the exact version of callback sent by camera service.
+ *
* @return status Status code for the operation, one of:
* OK:
* On a successful open of the camera device.
diff --git a/camera/device/3.2/ICameraDeviceSession.hal b/camera/device/3.2/ICameraDeviceSession.hal
index 477a3cc..225e52b 100644
--- a/camera/device/3.2/ICameraDeviceSession.hal
+++ b/camera/device/3.2/ICameraDeviceSession.hal
@@ -149,9 +149,8 @@
* - Including too many output streams of a certain format.
* - Unsupported rotation configuration
* - Stream sizes/formats don't satisfy the
- * camera3_stream_configuration_t->operation_mode requirements
- * for non-NORMAL mode, or the requested operation_mode is not
- * supported by the HAL.
+ * StreamConfigurationMode requirements for non-NORMAL mode, or
+ * the requested operation_mode is not supported by the HAL.
* - Unsupported usage flag
* The camera service cannot filter out all possible illegal stream
* configurations, since some devices may support more simultaneous
diff --git a/camera/device/3.4/ICameraDeviceSession.hal b/camera/device/3.4/ICameraDeviceSession.hal
index c41d90e..e1663e6 100644
--- a/camera/device/3.4/ICameraDeviceSession.hal
+++ b/camera/device/3.4/ICameraDeviceSession.hal
@@ -54,7 +54,7 @@
* - Including too many output streams of a certain format.
* - Unsupported rotation configuration
* - Stream sizes/formats don't satisfy the
- * camera3_stream_configuration_t->operation_mode requirements
+ * StreamConfigurationMode requirements
* for non-NORMAL mode, or the requested operation_mode is not
* supported by the HAL.
* - Unsupported usage flag
diff --git a/camera/device/3.5/Android.bp b/camera/device/3.5/Android.bp
index a4e9ee2..2a9ba05 100644
--- a/camera/device/3.5/Android.bp
+++ b/camera/device/3.5/Android.bp
@@ -7,7 +7,9 @@
enabled: true,
},
srcs: [
+ "types.hal",
"ICameraDevice.hal",
+ "ICameraDeviceCallback.hal",
"ICameraDeviceSession.hal",
],
interfaces: [
@@ -18,6 +20,14 @@
"android.hardware.graphics.common@1.0",
"android.hidl.base@1.0",
],
+ types: [
+ "BufferRequest",
+ "BufferRequestStatus",
+ "StreamBufferRequestError",
+ "StreamBufferRet",
+ "StreamBuffersVal",
+ "StreamConfiguration",
+ ],
gen_java: false,
}
diff --git a/camera/device/3.5/ICameraDeviceCallback.hal b/camera/device/3.5/ICameraDeviceCallback.hal
new file mode 100644
index 0000000..aa4ad22
--- /dev/null
+++ b/camera/device/3.5/ICameraDeviceCallback.hal
@@ -0,0 +1,70 @@
+/*
+ * Copyright (C) 2018 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.hardware.camera.device@3.5;
+
+import @3.2::StreamBuffer;
+import @3.4::ICameraDeviceCallback;
+
+/**
+ * Callback methods for the HAL to call into the framework.
+ */
+interface ICameraDeviceCallback extends @3.4::ICameraDeviceCallback {
+
+ /**
+ * requestStreamBuffers:
+ *
+ * Synchronous callback for HAL to ask for output buffers from camera service.
+ *
+ * This call may be serialized in camera service so it is strongly
+ * recommended to only call this method from one thread.
+ *
+ * When camera device advertises
+ * (CameraMetadataEnumAndroidInfoSupportedBufferManagementVersion ==
+ * ANDROID_INFO_SUPPORTED_BUFFER_MANAGEMENT_VERSION_HIDL_DEVICE_3_5), HAL
+ * can use this method to request buffers from camera service.
+ *
+ * @return status Status code for the operation, one of:
+ * OK: all requested buffers are returned
+ * FAILED_PARTIAL: some streams failed while some succeeds. Check
+ * individual StreamBufferRet for details.
+ * FAILED_CONFIGURING: the request failed because camera servicve is
+ * performing configureStreams and no buffers are returned.
+ * FAILED_UNKNOWN: the request failed for unknown reason and no buffers
+ * are returned.
+ *
+ * Performance requirements:
+ * This is a blocking call that takes more time with more buffers requested.
+ * HAL must not request large amount of buffers on a latency critical code
+ * path. It is highly recommended to use a dedicated thread to perform
+ * all requestStreamBuffers calls, and adjust the thread priority and/or
+ * timing of making the call in order for buffers to arrive before HAL is
+ * ready to fill the buffer.
+ */
+ requestStreamBuffers(vec<BufferRequest> bufReqs)
+ generates (BufferRequestStatus st, vec<StreamBufferRet> buffers);
+
+ /**
+ * returnStreamBuffers:
+ *
+ * Synchronous callback for HAL to return output buffers to camera service.
+ *
+ * If this method is called during a configureStreams call, it must be blocked
+ * until camera service finishes the ongoing configureStreams call.
+ */
+ returnStreamBuffers(vec<StreamBuffer> buffers);
+
+};
diff --git a/camera/device/3.5/ICameraDeviceSession.hal b/camera/device/3.5/ICameraDeviceSession.hal
index 8406685..b2b71cd 100644
--- a/camera/device/3.5/ICameraDeviceSession.hal
+++ b/camera/device/3.5/ICameraDeviceSession.hal
@@ -18,6 +18,7 @@
import android.hardware.camera.common@1.0::Status;
import @3.4::ICameraDeviceSession;
+import @3.4::HalStreamConfiguration;
/**
* Camera device active session interface.
@@ -26,4 +27,76 @@
* configure and request captures from an active camera device.
*/
interface ICameraDeviceSession extends @3.4::ICameraDeviceSession {
+
+ /**
+ * configureStreams_3_5:
+ *
+ * Identical to @3.4::ICameraDeviceSession.configureStreams, except that:
+ *
+ * - a streamConfigCounter counter is provided to check for race condition
+ * between configureStreams_3_5 and signalStreamFlush call.
+ *
+ * @return status Status code for the operation, one of:
+ * OK:
+ * On successful stream configuration.
+ * INTERNAL_ERROR:
+ * If there has been a fatal error and the device is no longer
+ * operational. Only close() can be called successfully by the
+ * framework after this error is returned.
+ * ILLEGAL_ARGUMENT:
+ * If the requested stream configuration is invalid. Some examples
+ * of invalid stream configurations include:
+ * - Including more than 1 INPUT stream
+ * - Not including any OUTPUT streams
+ * - Including streams with unsupported formats, or an unsupported
+ * size for that format.
+ * - Including too many output streams of a certain format.
+ * - Unsupported rotation configuration
+ * - Stream sizes/formats don't satisfy the
+ * StreamConfigurationMode requirements
+ * for non-NORMAL mode, or the requested operation_mode is not
+ * supported by the HAL.
+ * - Unsupported usage flag
+ * The camera service cannot filter out all possible illegal stream
+ * configurations, since some devices may support more simultaneous
+ * streams or larger stream resolutions than the minimum required
+ * for a given camera device hardware level. The HAL must return an
+ * ILLEGAL_ARGUMENT for any unsupported stream set, and then be
+ * ready to accept a future valid stream configuration in a later
+ * configureStreams call.
+ * @return halConfiguration The stream parameters desired by the HAL for
+ * each stream, including maximum buffers, the usage flags, and the
+ * override format.
+ */
+ configureStreams_3_5(@3.5::StreamConfiguration requestedConfiguration)
+ generates (Status status,
+ @3.4::HalStreamConfiguration halConfiguration);
+
+
+ /**
+ * signalStreamFlush:
+ *
+ * Signaling HAL camera service is about to perform configureStreams_3_5 and
+ * HAL must return all buffers of designated streams. HAL must finish
+ * inflight requests normally and return all buffers that belongs to the
+ * designated streams through processCaptureResult or returnStreamBuffer
+ * API in a timely manner, or camera service will run into a fatal error.
+ *
+ * Note that this call serves as an optional hint and camera service may
+ * skip sending this call if all buffers are already returned.
+ *
+ * @param streamIds The ID of streams camera service need all of its
+ * buffers returned.
+ *
+ * @param streamConfigCounter Note that due to concurrency nature, it is
+ * possible the signalStreamFlush call arrives later than the
+ * corresponding configureStreams_3_5 call, HAL must check
+ * streamConfigCounter for such race condition. If the counter is less
+ * than the counter in the last configureStreams_3_5 call HAL last
+ * received, the call is stale and HAL should just return this call.
+ */
+ oneway signalStreamFlush(
+ vec<int32_t> streamIds,
+ uint32_t streamConfigCounter
+ );
};
diff --git a/camera/device/3.5/default/Android.bp b/camera/device/3.5/default/Android.bp
index 341f573..09cf3a4 100644
--- a/camera/device/3.5/default/Android.bp
+++ b/camera/device/3.5/default/Android.bp
@@ -27,6 +27,7 @@
vendor: true,
srcs: [
"CameraDevice.cpp",
+ "CameraDeviceSession.cpp",
],
shared_libs: [
"libhidlbase",
diff --git a/camera/device/3.5/default/CameraDevice.cpp b/camera/device/3.5/default/CameraDevice.cpp
index fcd1c96..c5d6c57 100644
--- a/camera/device/3.5/default/CameraDevice.cpp
+++ b/camera/device/3.5/default/CameraDevice.cpp
@@ -39,6 +39,22 @@
CameraDevice::~CameraDevice() {
}
+sp<V3_2::implementation::CameraDeviceSession> CameraDevice::createSession(camera3_device_t* device,
+ const camera_metadata_t* deviceInfo,
+ const sp<V3_2::ICameraDeviceCallback>& callback) {
+ sp<CameraDeviceSession> session = new CameraDeviceSession(device, deviceInfo, callback);
+ IF_ALOGV() {
+ session->getInterface()->interfaceChain([](
+ ::android::hardware::hidl_vec<::android::hardware::hidl_string> interfaceChain) {
+ ALOGV("Session interface chain:");
+ for (auto iface : interfaceChain) {
+ ALOGV(" %s", iface.c_str());
+ }
+ });
+ }
+ return session;
+}
+
Return<void> CameraDevice::getPhysicalCameraCharacteristics(const hidl_string& physicalCameraId,
V3_5::ICameraDevice::getPhysicalCameraCharacteristics_cb _hidl_cb) {
Status status = initStatus();
diff --git a/camera/device/3.5/default/CameraDeviceSession.cpp b/camera/device/3.5/default/CameraDeviceSession.cpp
new file mode 100644
index 0000000..5336ca9
--- /dev/null
+++ b/camera/device/3.5/default/CameraDeviceSession.cpp
@@ -0,0 +1,68 @@
+/*
+ * Copyright (C) 2018 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#define LOG_TAG "CamDevSession@3.5-impl"
+#include <android/log.h>
+
+#include <utils/Trace.h>
+#include "CameraDeviceSession.h"
+
+namespace android {
+namespace hardware {
+namespace camera {
+namespace device {
+namespace V3_5 {
+namespace implementation {
+
+CameraDeviceSession::CameraDeviceSession(
+ camera3_device_t* device,
+ const camera_metadata_t* deviceInfo,
+ const sp<V3_2::ICameraDeviceCallback>& callback) :
+ V3_4::implementation::CameraDeviceSession(device, deviceInfo, callback) {
+
+ mHasCallback_3_5 = false;
+
+ auto castResult = ICameraDeviceCallback::castFrom(callback);
+ if (castResult.isOk()) {
+ sp<ICameraDeviceCallback> callback3_5 = castResult;
+ if (callback3_5 != nullptr) {
+ mHasCallback_3_5 = true;
+ }
+ }
+}
+
+CameraDeviceSession::~CameraDeviceSession() {
+}
+
+Return<void> CameraDeviceSession::configureStreams_3_5(
+ const StreamConfiguration& /*requestedConfiguration*/,
+ ICameraDeviceSession::configureStreams_3_5_cb _hidl_cb) {
+ HalStreamConfiguration outStreams;
+ _hidl_cb(Status::OPERATION_NOT_SUPPORTED, outStreams);
+ return Void();
+}
+
+Return<void> CameraDeviceSession::signalStreamFlush(
+ const hidl_vec<int32_t>& /*requests*/, uint32_t /*streamConfigCounter*/) {
+ return Void();
+}
+
+} // namespace implementation
+} // namespace V3_5
+} // namespace device
+} // namespace camera
+} // namespace hardware
+} // namespace android
diff --git a/camera/device/3.5/default/include/device_v3_5_impl/CameraDeviceSession.h b/camera/device/3.5/default/include/device_v3_5_impl/CameraDeviceSession.h
new file mode 100644
index 0000000..ec34769
--- /dev/null
+++ b/camera/device/3.5/default/include/device_v3_5_impl/CameraDeviceSession.h
@@ -0,0 +1,157 @@
+/*
+ * Copyright (C) 2018 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef ANDROID_HARDWARE_CAMERA_DEVICE_V3_5_CAMERADEVICE3SESSION_H
+#define ANDROID_HARDWARE_CAMERA_DEVICE_V3_5_CAMERADEVICE3SESSION_H
+
+#include <android/hardware/camera/device/3.5/ICameraDevice.h>
+#include <android/hardware/camera/device/3.5/ICameraDeviceSession.h>
+#include <android/hardware/camera/device/3.5/ICameraDeviceCallback.h>
+#include <../../3.4/default/include/device_v3_4_impl/CameraDeviceSession.h>
+
+namespace android {
+namespace hardware {
+namespace camera {
+namespace device {
+namespace V3_5 {
+namespace implementation {
+
+using namespace ::android::hardware::camera::device;
+using ::android::hardware::camera::device::V3_2::CaptureRequest;
+using ::android::hardware::camera::device::V3_5::StreamConfiguration;
+using ::android::hardware::camera::device::V3_4::HalStreamConfiguration;
+using ::android::hardware::camera::device::V3_5::ICameraDeviceSession;
+using ::android::hardware::camera::device::V3_5::ICameraDeviceCallback;
+using ::android::hardware::camera::common::V1_0::Status;
+using ::android::hardware::camera::common::V1_0::helper::HandleImporter;
+using ::android::hardware::Return;
+using ::android::hardware::Void;
+using ::android::hardware::hidl_vec;
+using ::android::hardware::hidl_string;
+using ::android::sp;
+using ::android::Mutex;
+
+struct CameraDeviceSession : public V3_4::implementation::CameraDeviceSession {
+
+ CameraDeviceSession(camera3_device_t*,
+ const camera_metadata_t* deviceInfo,
+ const sp<V3_2::ICameraDeviceCallback>&);
+ virtual ~CameraDeviceSession();
+
+ virtual sp<V3_2::ICameraDeviceSession> getInterface() override {
+ return new TrampolineSessionInterface_3_5(this);
+ }
+
+protected:
+ // Methods from v3.4 and earlier will trampoline to inherited implementation
+ Return<void> configureStreams_3_5(
+ const StreamConfiguration& requestedConfiguration,
+ ICameraDeviceSession::configureStreams_3_5_cb _hidl_cb);
+
+ Return<void> signalStreamFlush(
+ const hidl_vec<int32_t>& requests,
+ uint32_t streamConfigCounter);
+
+
+ // Whether this camera device session is created with version 3.5 callback.
+ bool mHasCallback_3_5;
+
+private:
+
+ struct TrampolineSessionInterface_3_5 : public ICameraDeviceSession {
+ TrampolineSessionInterface_3_5(sp<CameraDeviceSession> parent) :
+ mParent(parent) {}
+
+ virtual Return<void> constructDefaultRequestSettings(
+ V3_2::RequestTemplate type,
+ V3_3::ICameraDeviceSession::constructDefaultRequestSettings_cb _hidl_cb) override {
+ return mParent->constructDefaultRequestSettings(type, _hidl_cb);
+ }
+
+ virtual Return<void> configureStreams(
+ const V3_2::StreamConfiguration& requestedConfiguration,
+ V3_3::ICameraDeviceSession::configureStreams_cb _hidl_cb) override {
+ return mParent->configureStreams(requestedConfiguration, _hidl_cb);
+ }
+
+ virtual Return<void> processCaptureRequest_3_4(
+ const hidl_vec<V3_4::CaptureRequest>& requests,
+ const hidl_vec<V3_2::BufferCache>& cachesToRemove,
+ ICameraDeviceSession::processCaptureRequest_3_4_cb _hidl_cb) override {
+ return mParent->processCaptureRequest_3_4(requests, cachesToRemove, _hidl_cb);
+ }
+
+ virtual Return<void> processCaptureRequest(const hidl_vec<V3_2::CaptureRequest>& requests,
+ const hidl_vec<V3_2::BufferCache>& cachesToRemove,
+ V3_3::ICameraDeviceSession::processCaptureRequest_cb _hidl_cb) override {
+ return mParent->processCaptureRequest(requests, cachesToRemove, _hidl_cb);
+ }
+
+ virtual Return<void> getCaptureRequestMetadataQueue(
+ V3_3::ICameraDeviceSession::getCaptureRequestMetadataQueue_cb _hidl_cb) override {
+ return mParent->getCaptureRequestMetadataQueue(_hidl_cb);
+ }
+
+ virtual Return<void> getCaptureResultMetadataQueue(
+ V3_3::ICameraDeviceSession::getCaptureResultMetadataQueue_cb _hidl_cb) override {
+ return mParent->getCaptureResultMetadataQueue(_hidl_cb);
+ }
+
+ virtual Return<Status> flush() override {
+ return mParent->flush();
+ }
+
+ virtual Return<void> close() override {
+ return mParent->close();
+ }
+
+ virtual Return<void> configureStreams_3_3(
+ const V3_2::StreamConfiguration& requestedConfiguration,
+ configureStreams_3_3_cb _hidl_cb) override {
+ return mParent->configureStreams_3_3(requestedConfiguration, _hidl_cb);
+ }
+
+ virtual Return<void> configureStreams_3_4(
+ const V3_4::StreamConfiguration& requestedConfiguration,
+ configureStreams_3_4_cb _hidl_cb) override {
+ return mParent->configureStreams_3_4(requestedConfiguration, _hidl_cb);
+ }
+
+ virtual Return<void> configureStreams_3_5(
+ const StreamConfiguration& requestedConfiguration,
+ configureStreams_3_5_cb _hidl_cb) override {
+ return mParent->configureStreams_3_5(requestedConfiguration, _hidl_cb);
+ }
+
+ virtual Return<void> signalStreamFlush(
+ const hidl_vec<int32_t>& requests,
+ uint32_t streamConfigCounter) override {
+ return mParent->signalStreamFlush(requests, streamConfigCounter);
+ }
+
+ private:
+ sp<CameraDeviceSession> mParent;
+ };
+};
+
+} // namespace implementation
+} // namespace V3_5
+} // namespace device
+} // namespace camera
+} // namespace hardware
+} // namespace android
+
+#endif // ANDROID_HARDWARE_CAMERA_DEVICE_V3_5_CAMERADEVICE3SESSION_H
diff --git a/camera/device/3.5/default/include/device_v3_5_impl/CameraDevice_3_5.h b/camera/device/3.5/default/include/device_v3_5_impl/CameraDevice_3_5.h
index f250bc9..6bdc60f 100644
--- a/camera/device/3.5/default/include/device_v3_5_impl/CameraDevice_3_5.h
+++ b/camera/device/3.5/default/include/device_v3_5_impl/CameraDevice_3_5.h
@@ -17,7 +17,7 @@
#ifndef ANDROID_HARDWARE_CAMERA_DEVICE_V3_5_CAMERADEVICE_H
#define ANDROID_HARDWARE_CAMERA_DEVICE_V3_5_CAMERADEVICE_H
-#include "CameraModule.h"
+#include "CameraDeviceSession.h"
#include <../../../../3.4/default/include/device_v3_4_impl/CameraDevice_3_4.h>
#include <android/hardware/camera/device/3.5/ICameraDevice.h>
@@ -57,6 +57,10 @@
}
protected:
+ virtual sp<V3_2::implementation::CameraDeviceSession> createSession(camera3_device_t*,
+ const camera_metadata_t* deviceInfo,
+ const sp<V3_2::ICameraDeviceCallback>&) override;
+
Return<void> getPhysicalCameraCharacteristics(const hidl_string& physicalCameraId,
V3_5::ICameraDevice::getPhysicalCameraCharacteristics_cb _hidl_cb);
diff --git a/camera/device/3.5/types.hal b/camera/device/3.5/types.hal
new file mode 100644
index 0000000..613187d
--- /dev/null
+++ b/camera/device/3.5/types.hal
@@ -0,0 +1,131 @@
+/*
+ * Copyright (C) 2018 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.hardware.camera.device@3.5;
+
+import @3.2::StreamBuffer;
+import @3.4::StreamConfiguration;
+
+/**
+ * StreamConfiguration:
+ *
+ * Identical to @3.4::StreamConfiguration, except that it contains streamConfigCounter
+ */
+struct StreamConfiguration {
+ @3.4::StreamConfiguration v3_4;
+
+ /**
+ * An incrementing counter used for HAL to keep track of the stream
+ * configuration and the paired oneway signalStreamFlush call. When the
+ * counter in signalStreamFlush call is less than the counter here, that
+ * signalStreamFlush call is stale.
+ */
+ uint32_t streamConfigCounter;
+};
+
+enum StreamBufferRequestError : uint32_t {
+ /**
+ * Get buffer failed due to timeout waiting for an available buffer. This is
+ * likely due to the client application holding too many buffers, or the
+ * system is under memory pressure.
+ * This is not a fatal error. HAL may try to request buffer for this stream
+ * later. If HAL cannot get a buffer for certain capture request in time
+ * due to this error, HAL can send an ERROR_REQUEST to camera service and
+ * drop processing that request.
+ */
+ NO_BUFFER_AVAILABLE = 1,
+
+ /**
+ * Get buffer failed due to HAL has reached its maxBuffer count. This is not
+ * a fatal error. HAL may try to request buffer for this stream again after
+ * it returns at least one buffer of that stream to camera service.
+ */
+ MAX_BUFFER_EXCEEDED = 2,
+
+ /**
+ * Get buffer failed due to the stream is disconnected by client
+ * application, has been removed, or not recognized by camera service.
+ * This means application is no longer interested in this stream.
+ * Requesting buffer for this stream must never succeed after this error is
+ * returned. HAL must safely return all buffers of this stream after
+ * getting this error. If HAL gets another capture request later targeting
+ * a disconnected stream, HAL must send an ERROR_REQUEST to camera service
+ * and drop processing that request.
+ */
+ STREAM_DISCONNECTED = 3,
+
+ /**
+ * Get buffer failed for unknown reasons. This is a fatal error and HAL must
+ * send ERROR_DEVICE to camera service and be ready to be closed.
+ */
+ UNKNOWN_ERROR = 4
+};
+
+/**
+ * Per-stream return value for requestStreamBuffers.
+ * For each stream, either an StreamBufferRequestError error code, or all
+ * requested buffers for this stream is returned, so buffers.size() must be
+ * equal to BufferRequest::numBuffersRequested of corresponding stream.
+ */
+safe_union StreamBuffersVal {
+ StreamBufferRequestError error;
+ vec<@3.2::StreamBuffer> buffers;
+};
+
+struct StreamBufferRet {
+ int32_t streamId;
+ StreamBuffersVal val;
+};
+
+enum BufferRequestStatus : uint32_t {
+ /**
+ * Method call succeeded and all requested buffers are returned.
+ */
+ OK = 0,
+
+ /**
+ * Method call failed for some streams. Check per stream status for each
+ * returned StreamBufferRet.
+ */
+ FAILED_PARTIAL = 1,
+
+ /**
+ * Method call failed for all streams and no buffers are returned at all.
+ * Camera service is about to or is performing configureStreams. HAL must
+ * wait until next configureStreams call is finished before requesting
+ * buffers again.
+ */
+ FAILED_CONFIGURING = 2,
+
+ /**
+ * Method call failed for all streams and no buffers are returned at all.
+ * Failure due to bad BufferRequest input, eg: unknown streamId or repeated
+ * streamId.
+ */
+ FAILED_ILLEGAL_ARGUMENTS = 3,
+
+ /**
+ * Method call failed for all streams and no buffers are returned at all.
+ * Failure due to unknown reason.
+ */
+ FAILED_UNKNOWN = 4,
+};
+
+struct BufferRequest {
+ int32_t streamId;
+ uint32_t numBuffersRequested;
+};
+