Fix more race conditions.

In the old NXP JNI:
- We can be in the process of discovering a tag/p2p target
  when we try to configure discovery. In case ConfigureDiscovery
  returns BUSY, don't immediately call abort(), but retry a few
  times.
- Completely disable Tag/P2P discovery *before* opening a pipe
  to the SMX. This avoids nasty races with opening the SMX
  while a P2P/Tag device enters the field.

Bug: 8552749
Change-Id: I433a40c918373c661abda3bc40dd36db7b233245

2 files changed, 34 insertions, 2 deletions

diff --git a/nxp/jni/com_android_nfc_NativeNfcManager.cpp b/nxp/jni/com_android_nfc_NativeNfcManager.cpp
index 098f8a72..e144ea99 100644
--- a/nxp/jni/com_android_nfc_NativeNfcManager.cpp
+++ b/nxp/jni/com_android_nfc_NativeNfcManager.cpp
@@ -1305,6 +1305,7 @@ static void nfc_jni_start_discovery_locked(struct nfc_jni_native_data *nat, bool
 {
    NFCSTATUS ret;
    struct nfc_jni_callback_data cb_data;
+   int numRetries = 3;
 
    /* Create the local semaphore */
    if (!nfc_cb_data_init(&cb_data, NULL))
@@ -1321,7 +1322,7 @@ static void nfc_jni_start_discovery_locked(struct nfc_jni_native_data *nat, bool
 
    /* Reset device connected flag */
    device_connected_flag = 0;
-
+configure:
    /* Start Polling loop */
    TRACE("******  Start NFC Discovery ******");
    REENTRANCE_LOCK();
@@ -1338,6 +1339,13 @@ static void nfc_jni_start_discovery_locked(struct nfc_jni_native_data *nat, bool
       nat->discovery_cfg.PollDevInfo.PollCfgInfo.DisableCardEmulation==FALSE?"CE":"",
       nat->discovery_cfg.NfcIP_Mode, nat->discovery_cfg.Duration, ret);
 
+   if (ret == NFCSTATUS_BUSY && numRetries-- > 0)
+   {
+      TRACE("ConfigDiscovery BUSY, retrying");
+      usleep(1000000);
+      goto configure;
+   }
+
    if(ret != NFCSTATUS_PENDING)
    {
       emergency_recovery(nat);
@@ -1360,6 +1368,7 @@ static void nfc_jni_stop_discovery_locked(struct nfc_jni_native_data *nat)
    phLibNfc_sADD_Cfg_t discovery_cfg;
    NFCSTATUS ret;
    struct nfc_jni_callback_data cb_data;
+   int numRetries = 3;
 
    /* Create the local semaphore */
    if (!nfc_cb_data_init(&cb_data, NULL))
@@ -1372,6 +1381,7 @@ static void nfc_jni_stop_discovery_locked(struct nfc_jni_native_data *nat)
    discovery_cfg.NfcIP_Target_Mode = 0;
    discovery_cfg.NfcIP_Tgt_Disable = TRUE;
 
+configure:
    /* Start Polling loop */
    TRACE("******  Stop NFC Discovery ******");
    REENTRANCE_LOCK();
@@ -1387,8 +1397,16 @@ static void nfc_jni_stop_discovery_locked(struct nfc_jni_native_data *nat)
       discovery_cfg.PollDevInfo.PollCfgInfo.DisableCardEmulation==FALSE?"CE":"",
       discovery_cfg.NfcIP_Mode, discovery_cfg.Duration, ret);
 
+   if (ret == NFCSTATUS_BUSY && numRetries-- > 0)
+   {
+      TRACE("ConfigDiscovery BUSY, retrying");
+      usleep(1000000);
+      goto configure;
+   }
+
    if(ret != NFCSTATUS_PENDING)
    {
+      ALOGE("[STOP] ConfigDiscovery returned %x", ret);
       emergency_recovery(nat);
    }
 
diff --git a/src/com/android/nfc/NfcService.java b/src/com/android/nfc/NfcService.java
index 306b7066..f6ca3b55 100755
--- a/src/com/android/nfc/NfcService.java
+++ b/src/com/android/nfc/NfcService.java
@@ -1406,8 +1406,23 @@ public class NfcService implements DeviceHostListener {
                     return EE_ERROR_ALREADY_OPEN;
                 }
 
+                boolean restorePolling = false;
+                if (mDeviceHost.enablePN544Quirks() && mNfcPollingEnabled) {
+                    // Disable polling for tags/P2P when connecting to the SMX
+                    // on PN544-based devices. Whenever nfceeClose is called,
+                    // the polling configuration will be restored.
+                    mDeviceHost.disableDiscovery();
+                    mNfcPollingEnabled = false;
+                    restorePolling = true;
+                }
+
                 int handle = doOpenSecureElementConnection();
                 if (handle < 0) {
+
+                    if (restorePolling) {
+                        mDeviceHost.enableDiscovery();
+                        mNfcPollingEnabled = true;
+                    }
                     return handle;
                 }
                 mDeviceHost.setTimeout(TagTechnology.ISO_DEP, 30000);
@@ -1938,7 +1953,6 @@ public class NfcService implements DeviceHostListener {
                     sendSeBroadcast(listenModeDeactivated);
                     break;
                 }
-
                 default:
                     Log.e(TAG, "Unknown message received");
                     break;