FM Radio: Wait for disable to complete

Make disable fm to be synchronous. On factory reset, disable fm
and enable fm called back to back. If enable fm command sent before
disable fm completes, fm enable fails. Hence wait for disable fm
to complete.

Change-Id: Ic3630f7bdd39ca812d9ae81b45a9c496049aef84

fm_hci/fm_hci.c

@@ -677,6 +677,12 @@ void fm_hci_close(void *arg) {
         return;
     }
     event_notification(hci, HC_EVENT_EXIT);
+    pthread_mutex_lock(&hci->event_lock);
+again:
+    pthread_cond_wait(&hci->event_cond, &hci->event_lock);
+    if (!(ready_events & HC_EVENT_EXIT_DONE))
+        goto again;
+    pthread_mutex_unlock(&hci->event_lock);
 }
 
 int fm_hci_init(fm_hci_hal_t *hci_hal)
@@ -785,6 +791,7 @@ static void fm_hci_exit(void *arg)
     vendor_close(hci);
     pthread_cond_broadcast(&hci->event_cond);
     pthread_cond_broadcast(&hci->cmd_credits_cond);
+    event_notification(hci, HC_EVENT_EXIT_DONE);
     stop_rx_thread(hci);
     stop_tx_thread(hci);
     ALOGD("Tx, Rx Threads join done");

fm_hci/fm_hci.h

@@ -46,6 +46,7 @@
 #define HC_EVENT_LPM_IDLE_TIMEOUT      0x0100
 #define HC_EVENT_EXIT                  0x0200
 #define HC_EVENT_EPILOG                0x0400
+#define HC_EVENT_EXIT_DONE             0x8000
 
 #define MAX_FM_CMD_CNT                 100
 #define FM_CMD                         0x11