power: Allow devices disabling power stats completely

* On some devices even attempting to read the stats nodes results
  in kernel lockup and reboot from watchdog bite.
  This has been noticed on a lot of msm8916 devices, so add a way
  to disable stats completely in order to allow using the binderized
  power HAL and get rid of the old one from device/qcom/common

Change-Id: I134c40548dd883aaf72cf0c212be978305366521

2 files changed, 10 insertions, 0 deletions

diff --git a/Android.mk b/Android.mk
index 09d659a..2a24ad6 100644
--- a/Android.mk
+++ b/Android.mk
@@ -134,6 +134,10 @@ ifeq ($(TARGET_HAS_LEGACY_POWER_STATS),true)
     LOCAL_CFLAGS += -DLEGACY_STATS
 endif
 
+ifeq ($(TARGET_HAS_NO_POWER_STATS),true)
+    LOCAL_CFLAGS += -DNO_STATS
+endif
+
 ifneq ($(TARGET_RPM_STAT),)
     LOCAL_CFLAGS += -DRPM_STAT=\"$(TARGET_RPM_STAT)\"
 endif
diff --git a/Power.cpp b/Power.cpp
index f857041..eb4a746 100644
--- a/Power.cpp
+++ b/Power.cpp
@@ -76,6 +76,11 @@ Return<void> Power::setFeature(Feature feature, bool activate)  {
 
 Return<void> Power::getPlatformLowPowerStats(getPlatformLowPowerStats_cb _hidl_cb) {
     hidl_vec<PowerStatePlatformSleepState> states;
+#ifdef NO_STATS
+    states.resize(0);
+    _hidl_cb(states, Status::SUCCESS);
+    return Void();
+#else
     uint64_t stats[MAX_PLATFORM_STATS * MAX_RPM_PARAMS] = {0};
 #ifndef LEGACY_STATS
     uint64_t *values;
@@ -168,6 +173,7 @@ Return<void> Power::getPlatformLowPowerStats(getPlatformLowPowerStats_cb _hidl_c
 done:
     _hidl_cb(states, Status::SUCCESS);
     return Void();
+#endif
 }
 
 #ifndef V1_0_HAL