contexthub: Expose CHRE version information
Add chrePlatformId and chreVersion fields to context hub metadata
returned by getHubs(). This information will be used to make
compatibility decisions at runtime. Also, add a brief description of
CHRE to the IContexthub documentation to help clarify the
relationship between the HAL and these concepts in the CHRE API.
Bug: 31402693
Test: compile test only, this only adds fields to HIDL structures
Change-Id: Iea2436ccc23b47c4cf06040bebe1c550fe58ccb7
diff --git a/contexthub/1.0/IContexthub.hal b/contexthub/1.0/IContexthub.hal
index 8c792fd..a9b8fdb 100644
--- a/contexthub/1.0/IContexthub.hal
+++ b/contexthub/1.0/IContexthub.hal
@@ -18,6 +18,13 @@
import IContexthubCallback;
+/*
+ * The Context Hub HAL provides an interface to a separate low-power processing
+ * domain that has direct access to contextual information, such as sensors.
+ * Native applications that run within a context hub are known as nanoapps, and
+ * they execute within the Context Hub Runtime Environment (CHRE), which is
+ * standardized via the CHRE API, defined elsewhere.
+ */
interface IContexthub {
/*
* Enumerate all available context hubs on the system.