From dce3654d919012925f4c0973ca712b74e9f0c7ac Mon Sep 17 00:00:00 2001
From: Sushil Chauhan <sushilchauhan@codeaurora.org>
Date: Fri, 3 Mar 2017 18:17:31 -0800
Subject: [PATCH] sdm: Reset the H/W layers of display

SDM does not reset the H/W layers for the use case, when there are no
App layers present in the draw cycle. It leads to crash in SF dumpsys.
Hence, reset the H/W layers of display in all the use cases. Add SDM
error type which indicates the use case, when there are no App layers
in the draw cycle.

CRs-Fixed: 2008789
Change-Id: Ia0c0d237e6e4033993b8d2e46b6a792ff5f18340
---
 sdm/include/core/sdm_types.h         |  3 ++-
 sdm/libs/core/display_base.cpp       |  4 ++--
 sdm/libs/hwc/hwc_display.cpp         |  4 ++--
 sdm/libs/hwc/hwc_display_primary.cpp | 12 +++---------
 4 files changed, 9 insertions(+), 14 deletions(-)

diff --git a/sdm/include/core/sdm_types.h b/sdm/include/core/sdm_types.h
index 367ab380..fae11531 100644
--- a/sdm/include/core/sdm_types.h
+++ b/sdm/include/core/sdm_types.h
@@ -1,5 +1,5 @@
 /*
-* Copyright (c) 2014 - 2015, The Linux Foundation. All rights reserved.
+* Copyright (c) 2014 - 2017, The Linux Foundation. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
@@ -54,6 +54,7 @@ enum DisplayError {
   kErrorTimeOut,          //!< The operation has timed out to prevent client from waiting forever.
   kErrorShutDown,         //!< Driver is processing shutdown sequence
   kErrorPerfValidation,   //!< Bandwidth or Clock requirement validation failure.
+  kErrorNoAppLayers,      //!< No App layer(s) in the draw cycle.
 };
 
 /*! @brief This structure is defined for client and library compatibility check purpose only. This
diff --git a/sdm/libs/core/display_base.cpp b/sdm/libs/core/display_base.cpp
index 33785599..c6501bf9 100644
--- a/sdm/libs/core/display_base.cpp
+++ b/sdm/libs/core/display_base.cpp
@@ -156,8 +156,8 @@ DisplayError DisplayBase::BuildLayerStackStats(LayerStack *layer_stack) {
            hw_layers_info.gpu_target_index, display_type_);
 
   if (!hw_layers_info.app_layer_count) {
-    DLOGE("Layer count is zero");
-    return kErrorParameters;
+    DLOGW("Layer count is zero");
+    return kErrorNoAppLayers;
   }
 
   if (hw_layers_info.gpu_target_index) {
diff --git a/sdm/libs/hwc/hwc_display.cpp b/sdm/libs/hwc/hwc_display.cpp
index c1e41345..3437dcda 100644
--- a/sdm/libs/hwc/hwc_display.cpp
+++ b/sdm/libs/hwc/hwc_display.cpp
@@ -716,13 +716,13 @@ int HWCDisplay::PrepareLayerStack(hwc_display_contents_1_t *content_list) {
     if (error != kErrorNone) {
       if (error == kErrorShutDown) {
         shutdown_pending_ = true;
-      } else if (error != kErrorPermission) {
+      } else if ((error != kErrorPermission) && (error != kErrorNoAppLayers)) {
         DLOGE("Prepare failed. Error = %d", error);
         // To prevent surfaceflinger infinite wait, flush the previous frame during Commit()
         // so that previous buffer and fences are released, and override the error.
         flush_ = true;
       } else {
-        DLOGI("Prepare failed for Display = %d Error = %d", type_, error);
+        DLOGV("Prepare failed for Display = %d Error = %d", type_, error);
       }
       return 0;
     }
diff --git a/sdm/libs/hwc/hwc_display_primary.cpp b/sdm/libs/hwc/hwc_display_primary.cpp
index 8b0a6f2b..ba351b5b 100644
--- a/sdm/libs/hwc/hwc_display_primary.cpp
+++ b/sdm/libs/hwc/hwc_display_primary.cpp
@@ -1,5 +1,5 @@
 /*
-* Copyright (c) 2014 - 2016, The Linux Foundation. All rights reserved.
+* Copyright (c) 2014 - 2017, The Linux Foundation. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
@@ -208,14 +208,7 @@ int HWCDisplayPrimary::Prepare(hwc_display_contents_1_t *content_list) {
   }
 
   if (content_list->numHwLayers <= 1) {
-    DisplayConfigFixedInfo display_config;
-    display_intf_->GetConfig(&display_config);
-    if (display_config.is_cmdmode) {
-      DLOGV("Skipping null commit on cmd mode panel");
-    } else {
-      flush_ = true;
-    }
-    return 0;
+    flush_ = true;
   }
 
   status = PrepareLayerStack(content_list);
@@ -233,6 +226,7 @@ int HWCDisplayPrimary::Commit(hwc_display_contents_1_t *content_list) {
   display_intf_->GetConfig(&display_config);
   if (content_list->numHwLayers <= 1 && display_config.is_cmdmode) {
     DLOGV("Skipping null commit on cmd mode panel");
+    flush_ = false;
     return 0;
   }