[sensors] clarify sensor and direct channel handle size
* clarify direct channel handle must be less than INT32_MAX.
* sensor handle should fit in int32_t and positive.
Test: compiles ok
Change-Id: Iaf4573cf3a66b992fd354217096140a6001c4078
diff --git a/include/hardware/sensors.h b/include/hardware/sensors.h
index 807b074..8c5fa16 100644
--- a/include/hardware/sensors.h
+++ b/include/hardware/sensors.h
@@ -56,12 +56,14 @@
#define SENSORS_HARDWARE_POLL "poll"
/**
- * Handles must be higher than SENSORS_HANDLE_BASE and must be unique.
- * A Handle identifies a given sensors. The handle is used to activate
- * and/or deactivate sensors.
+ * Sensor handle is greater than 0 and less than INT32_MAX.
+ *
+ * **** Deprecated ****
+ * Defined values below are kept for code compatibility. Note sensor handle can be as large as
+ * INT32_MAX.
*/
#define SENSORS_HANDLE_BASE 0
-#define SENSORS_HANDLE_BITS 32
+#define SENSORS_HANDLE_BITS 31
#define SENSORS_HANDLE_COUNT (1ull<<SENSORS_HANDLE_BITS)
@@ -662,8 +664,8 @@
* mem points to a valid struct sensors_direct_mem_t.
* channel_handle is ignored.
* Return value:
- * A handle of channel (>0) when success, which later can be referred in
- * unregister or config_direct_report call, or error code (<0) if failed
+ * A handle of channel (>0, <INT32_MAX) when success, which later can be referred in
+ * unregister or config_direct_report call, or error code (<0) when failed
* Unregister: mem == NULL, unregister a previously registered channel.
* Parameters:
* mem set to NULL