[Raspberry Pi Original Development] gregory112:
The HAL actually works with "Open Camera" app that I downloaded from apkmirror. There are some errors like "StreamHAL: Error from HAL stream in function get_presentation_position: Operation not permitted" but the camera works nonetheless. However, there are some applications that do not work, for example Samsung Smartthings has a QR scanner in the app, and when run it threw errors like this:

10-25 09:14:58.325 1314 1314 I CameraPreview: Starting preview
10-25 09:14:58.325 1314 1875 D CameraInstance: Starting preview
10-25 09:14:58.329 191 364 E V4L2CameraHAL: setupStreams:362: V4L2 only supports 1 stream configuration at a time (stream 0 is format 34, width 640, height 360, stream 1 is format 33, width 160, height 120).
10-25 09:14:58.329 191 364 E Camera : configureStreams:0: Failed to setup stream set
10-25 09:14:58.329 191 364 E Camera3-Device: Camera 0: configureStreamsLocked: Set of requested inputs/outputs not supported by HAL
10-25 09:14:58.329 191 364 E Camera3-Device: Camera 0: setUpRequestLocked: Can't set up streams: Invalid argument (-22)
10-25 09:14:58.329 191 364 E Camera3-Device: Camera 0: convertMetadataListToRequestListLocked: Can't create capture request
10-25 09:14:58.330 191 364 E Camera2-StreamingProcessor: startStream: Camera 0: Unable to set preview request to start preview: Invalid argument (-22)
10-25 09:14:58.330 191 364 E Camera2Client: startPreviewL: Camera 0: Unable to start streaming preview: Invalid argument (-22)
10-25 09:14:58.335 1314 1875 E CameraInstance: Failed to start preview
10-25 09:14:58.335 1314 1875 E CameraInstance: java.lang.RuntimeException: startPreview failed
10-25 09:14:58.335 1314 1875 E CameraInstance:	at android.hardware.Camera.startPreview(Native Method)
10-25 09:14:58.335 1314 1875 E CameraInstance:	at com.journeyapps.barcodescanner.camera.CameraManager.c(Unknown Source:181)
10-25 09:14:58.335 1314 1875 E CameraInstance:	at com.journeyapps.barcodescanner.camera.CameraInstance$6.run(Unknown Source:248)
10-25 09:14:58.335 1314 1875 E CameraInstance:	at android.os.Handler.handleCallback(Handler.java:873)
10-25 09:14:58.335 1314 1875 E CameraInstance:	at android.os.Handler.dispatchMessage(Handler.java:99)
10-25 09:14:58.335 1314 1875 E CameraInstance:	at android.os.Looper.loop(Looper.java:193)
10-25 09:14:58.335 1314 1875 E CameraInstance:	at android.os.HandlerThread.run(HandlerThread.java:65)
10-25 09:14:58.440 1314 1314 D CameraPreview: pause()
10-25 09:14:58.440 1314 1314 W OrientationEventListener: Cannot detect sensors. Invalid disable
10-25 09:14:58.442 1314 1875 D CameraInstance: Closing camera
10-25 09:14:58.495 191 364 I Camera3-Device: disconnect: E
10-25 09:14:58.495 191 364 I Camera : close:0: Closing camera device
10-25 09:14:58.496 191 364 I Camera3-Device: disconnect: X
10-25 09:14:58.496 191 364 I Camera3-Device: disconnect: E
10-25 09:14:58.618 191 364 I CameraService: disconnect: Disconnected client for camera 0 for PID 1314
10-25 09:14:58.618 191 364 I Camera2Client: Camera 0: Closed
10-25 09:14:58.618 191 364 I Camera2ClientBase: Closed Camera 0. Client was: com.samsung.android.oneconnect (PID 1314, UID 10079)

I would like to ask in AOSP forum for helps about this and to read the codes but, well...