tree f507731c293eeba9fc208939db172095947faf8b
parent becd6bd4b68cc6594e2fe149da8de705a648b199
author mamik <mamik@google.com> 1566231093 -0700
committer mamik <mamik@google.com> 1567536871 -0700

Rev up vr_hwc to composer@2.3

Fix for issue: "[GSI XR] VrFlinger doesn't work on GSI/MTP845."

The flow that causes the issue is:
SurfaceFlinger gets an hotplug event and adds a display id of the
internal display (For instance, display id of 19260371107735809). This
display id gets added to the HWComposer through the hotplug event.

When updateVrFlinger() is eventually called in SurfaceFlinger, a new
HWComposer is created which has no display ids being tracked in
HWComposer. Another hotplug event starts from vr_hwc.cpp, which has a
display id of 0. SurfaceFlinger receives this hot plug event so
SurfaceFlinger has an display ids of [19260371107735809, 0]. HWComposer
only has display id 0.

Next processDisplayChangesLocked() is called in SurfaceFlinger and a new
FramebufferSurface is created with display id 19260371107735809.
In the FramebufferSurface it tries to call getActiveConfig() in
HWComposer with the display id of 19260371107735809, which HWComposer
does not know about. This results in a crash.

The display id is created from the edid data and display port.

The fix is to have the vr_hwc return the same edid data and display port
as the internal display. This will make the display id originating
from vr_hwc be the same as the internal display id. SurfaceFlinger
will now only have the display id of 19260371107735809, since it does not
overwrite the same display id on the hotplug events. HWComposer will only
have display id of 19260371107735809. The SurfaceFlinger and HwComposer
display ids match the code works correctly now.

This is accomplished by creating a version 2.0 of the vr_composer_client
and having vr_hwc inherit from version 2.3 instead of version 2.1 of the
composer hal. These changes are required to be able to pass through the
edid data. The display port and edid data is retrieved by vr_hwc via the
display_client.

The other required changes needed for this to work is:
ag/9215156
ag/9226524

Bug: 137325030
Bug: 138938154
Bug: 137448042

Test: manual - ran through modified unit test to make sure the edid data
was returned on the MTP 845.

Change-Id: I1c54e6cfda348260cf1013d6dca0dda58acb3b3c