android: Return -EUSERS when failed to open a Camera that's in use

The correct return value for the HAL for hal_dev_open() when trying to
open a camera that's already opened is EUSERS. Make hal_dev_open()
return -EUSERS, and plumb the logic for this through
CameraHalManager::open().

This allows the following CTS tests to pass:
- android.hardware.camera2.cts.CameraManagerTest#testCameraManagerOpenAllCameras
- android.hardware.camera2.cts.MultiViewTest#testDualCameraPreview

Signed-off-by: Paul Elder <paul.elder@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Hirokazu Honda <hiroh@chromium.org>
Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>

1 files changed, 8 insertions, 7 deletions

diff --git a/src/android/camera_hal_manager.cpp b/src/android/camera_hal_manager.cpp
index 189eda2b..aeff14bd 100644
--- a/src/android/camera_hal_manager.cpp
+++ b/src/android/camera_hal_manager.cpp
@@ -65,28 +65,29 @@ int CameraHalManager::init()
 	return 0;
 }
 
-CameraDevice *CameraHalManager::open(unsigned int id,
-				     const hw_module_t *hardwareModule)
+std::tuple<CameraDevice *, int>
+CameraHalManager::open(unsigned int id, const hw_module_t *hardwareModule)
 {
 	MutexLocker locker(mutex_);
 
 	if (!callbacks_) {
 		LOG(HAL, Error) << "Can't open camera before callbacks are set";
-		return nullptr;
+		return { nullptr, -ENODEV };
 	}
 
 	CameraDevice *camera = cameraDeviceFromHalId(id);
 	if (!camera) {
 		LOG(HAL, Error) << "Invalid camera id '" << id << "'";
-		return nullptr;
+		return { nullptr, -ENODEV };
 	}
 
-	if (camera->open(hardwareModule))
-		return nullptr;
+	int ret = camera->open(hardwareModule);
+	if (ret)
+		return { nullptr, ret };
 
 	LOG(HAL, Info) << "Open camera '" << id << "'";
 
-	return camera;
+	return { camera, 0 };
 }
 
 void CameraHalManager::cameraAdded(std::shared_ptr<Camera> cam)