[libcamera-devel] [RFC PATCH 0/2] android: Fix the issue with Type::Mapped only request

[Hirokazu Honda]

We have the problem that no buffer is not provided to a native camera
if a request given in CameraDevice::processCaptureRequest() contains
only streams that are resolved as CameraStream::Type::Mapped in
CameraDevice::configureStreams(). See the example in below.

```
[0:27:06.863311142] [15203] DEBUG HAL camera_device.cpp:980
'\_SB_.PCI0.I2C2.CAM0': Queueing request 139090704005584 with 2
streams
[0:27:06.863389502] [15203] DEBUG HAL camera_device.cpp:1005
'\_SB_.PCI0.I2C2.CAM0': 0 - (320x240)[0x00000022] -> (320x240)[NV12]
(mapped)
[0:27:06.863436331] [15203] DEBUG HAL camera_device.cpp:1005
'\_SB_.PCI0.I2C2.CAM0': 1 - (320x240)[0x00000021] -> (320x240)[NV12]
(mapped)
[0:27:06.863487886] [15203] DEBUG HAL camera_device.cpp:1043
'\_SB_.PCI0.I2C2.CAM0': buffers=0
[0:27:06.863561912] [15218] ERROR Camera camera.cpp:1031 Request
contains no buffers
```

This patch series fixes the issue by looking up the stream
alternatively sent to a native camera. To do that, we have to
allocate a FrameBuffer for the stream. One possible way is to use
FrameBufferAllocator. However, FrameBufferAllocator::allocate must
be called when the state of Camera is Configured, but not Running.
So we have to allocate buffers during configureStreams(). But
allocating buffers for CameraStrems whose type is Direct wastes
memory as they tends to not be used at all.

I would rather have a new class that allocates FrameBuffers in a
platform-dependent way, cros::CameraBufferManager on ChromeOS and
gralloc API on other platforms.

With this patch, android.hardware.camera2.cts.SurfaceViewPreviewTest#testDeferredSurfaces passed.

Hirokazu Honda (2):
  android: Introduce PlatformFrameBufferAllocator
  android: Send alternative stream configuration if no buffer to be sent
    exists

 src/android/camera_device.cpp           |  50 ++++++++--
 src/android/camera_device.h             |   4 +
 src/android/camera_stream.cpp           |  37 +++++++-
 src/android/camera_stream.h             |  10 +-
 src/android/frame_buffer.h              |  53 +++++++++++
 src/android/mm/cros_frame_buffer.cpp    |  85 +++++++++++++++++
 src/android/mm/generic_frame_buffer.cpp | 116 ++++++++++++++++++++++++
 src/android/mm/meson.build              |   6 +-
 8 files changed, 344 insertions(+), 17 deletions(-)
 create mode 100644 src/android/frame_buffer.h
 create mode 100644 src/android/mm/cros_frame_buffer.cpp
 create mode 100644 src/android/mm/generic_frame_buffer.cpp

--
2.33.0.685.g46640cef36-goog