commit 8cbfc1846671c5bb1628de2ca42b6ca782fa8511
author Arnd Geis <arndg@google.com> Thu Sep 07 14:46:41 2017 -0700
committer Arnd Geis <arndg@google.com> Thu Sep 07 15:59:31 2017 -0700
tree 9ac0a5a306785e60fbce5f6485e94f0a858ec100
parent 31be5768327563b3f8b39c9ef0c95bed84b0f6fb

QCamera3: avoid race condition in getEaselFwVersion

Moved firmware version extraction to onOpened after easel is
booted and the firmware version is guaranteed to be correct.
This way a possible race condition for the mutex lock over
gHdrPlusClientLock from consecutive frame captures is averted.

Bug: 65458066

Change-Id: Ie7124ad008e1513cba5f60942df087e6d81396f3
Signed-off-by: Arnd Geis <arndg@google.com>

msm8998/QCamera2/HAL3/QCamera3HWI.cpp

diff --git a/msm8998/QCamera2/HAL3/QCamera3HWI.cpp b/msm8998/QCamera2/HAL3/QCamera3HWI.cpp
index 1f082b6..d35c65e 100644
--- a/msm8998/QCamera2/HAL3/QCamera3HWI.cpp
+++ b/msm8998/QCamera2/HAL3/QCamera3HWI.cpp
@@ -569,6 +569,7 @@
     memset(mLdafCalib, 0, sizeof(mLdafCalib));
 
     memset(mEaselFwVersion, 0, sizeof(mEaselFwVersion));
+    mEaselFwUpdated = false;
 
     memset(prop, 0, sizeof(prop));
     property_get("persist.camera.tnr.preview", prop, "0");
@@ -900,6 +901,7 @@
                 ALOGE("%s: Resuming Easel failed: %s (%d)", __FUNCTION__, strerror(-rc), rc);
                 return rc;
             }
+            mEaselFwUpdated = false;
         }
     }
 
@@ -14094,22 +14096,15 @@
 * PARAMETERS : None
 *
 * RETURN     : string describing Firmware version
-*              "\0" if Easel manager client is not open
+*              "\0" if version is not up to date
 *==========================================================================*/
 const char *QCamera3HardwareInterface::getEaselFwVersion()
 {
-    int rc = NO_ERROR;
-
-    std::unique_lock<std::mutex> l(gHdrPlusClientLock);
-    ALOGD("%s: Querying Easel firmware version", __FUNCTION__);
-    if (EaselManagerClientOpened) {
-        rc = gEaselManagerClient->getFwVersion(mEaselFwVersion);
-        if (rc != OK)
-            ALOGD("%s: Failed to query Easel firmware version", __FUNCTION__);
-        else
-            return (const char *)&mEaselFwVersion[0];
+    if (mEaselFwUpdated) {
+        return (const char *)&mEaselFwVersion[0];
+    } else {
+        return NULL;
     }
-    return NULL;
 }
 
 /*===========================================================================
@@ -15203,6 +15198,8 @@
 
 void QCamera3HardwareInterface::onOpened(std::unique_ptr<HdrPlusClient> client)
 {
+    int rc = NO_ERROR;
+
     if (client == nullptr) {
         ALOGE("%s: Opened client is null.", __FUNCTION__);
         return;
@@ -15236,6 +15233,16 @@
     if (res != OK) {
         LOGE("%s: Failed to configure HDR+ streams.", __FUNCTION__);
     }
+
+    // Get Easel firmware version
+    if (EaselManagerClientOpened) {
+        rc = gEaselManagerClient->getFwVersion(mEaselFwVersion);
+        if (rc != OK) {
+            ALOGD("%s: Failed to query Easel firmware version", __FUNCTION__);
+        } else {
+            mEaselFwUpdated = true;
+        }
+    }
 }
 
 void QCamera3HardwareInterface::onOpenFailed(status_t err)