Register v4l2 device to report heatmap data. Use MSC_TIMESTAMP events
to synchronize the video frames with the input events.
Now includes:
- Support for B1 and C1
- registering of the v4l-touch device in the touch driver
- data properly written to video frame
- timestamps are populated
- report msc_timestamp before sync, but read_heatmap after:
this informs user space that input event occurred, and allows the
i2c read to happen in parallel. Then, user space can wait on the frame
to become available.
Bug: 62940136
Test: used the HeatMapDemo app to visually confirm the output
Signed-off-by: Siarhei Vishniakou <svv@google.com>
Change-Id: Ib282a0c59849a07cac542c1cdc6ed2b3d035a6af
1cfc828536