1 files changed, 40 insertions, 2 deletions

diff --git a/libsuspend/autosuspend_earlysuspend.c b/libsuspend/autosuspend_earlysuspend.c
index b440128..1df8c6a 100644
--- a/libsuspend/autosuspend_earlysuspend.c
+++ b/libsuspend/autosuspend_earlysuspend.c
@@ -16,6 +16,8 @@
 
 #include <errno.h>
 #include <fcntl.h>
+#include <pthread.h>
+#include <stdbool.h>
 #include <stddef.h>
 #include <string.h>
 #include <sys/types.h>
@@ -31,11 +33,17 @@
 #define EARLYSUSPEND_WAIT_FOR_FB_SLEEP "/sys/power/wait_for_fb_sleep"
 #define EARLYSUSPEND_WAIT_FOR_FB_WAKE "/sys/power/wait_for_fb_wake"
 
-
 static int sPowerStatefd;
 static const char *pwr_state_mem = "mem";
 static const char *pwr_state_on = "on";
 static pthread_t earlysuspend_thread;
+static pthread_mutex_t earlysuspend_mutex = PTHREAD_MUTEX_INITIALIZER;
+static pthread_cond_t earlysuspend_cond = PTHREAD_COND_INITIALIZER;
+static bool wait_for_earlysuspend;
+static enum {
+    EARLYSUSPEND_ON,
+    EARLYSUSPEND_MEM,
+} earlysuspend_state = EARLYSUSPEND_ON;
 
 int wait_for_fb_wake(void)
 {
@@ -79,10 +87,19 @@ static void *earlysuspend_thread_func(void *arg)
             ALOGE("Failed reading wait_for_fb_sleep, exiting earlysuspend thread\n");
             return NULL;
         }
+        pthread_mutex_lock(&earlysuspend_mutex);
+        earlysuspend_state = EARLYSUSPEND_MEM;
+        pthread_cond_signal(&earlysuspend_cond);
+        pthread_mutex_unlock(&earlysuspend_mutex);
+
         if (wait_for_fb_wake()) {
             ALOGE("Failed reading wait_for_fb_wake, exiting earlysuspend thread\n");
             return NULL;
         }
+        pthread_mutex_lock(&earlysuspend_mutex);
+        earlysuspend_state = EARLYSUSPEND_ON;
+        pthread_cond_signal(&earlysuspend_cond);
+        pthread_mutex_unlock(&earlysuspend_mutex);
     }
 }
 static int autosuspend_earlysuspend_enable(void)
@@ -99,6 +116,14 @@ static int autosuspend_earlysuspend_enable(void)
         goto err;
     }
 
+    if (wait_for_earlysuspend) {
+        pthread_mutex_lock(&earlysuspend_mutex);
+        while (earlysuspend_state != EARLYSUSPEND_MEM) {
+            pthread_cond_wait(&earlysuspend_cond, &earlysuspend_mutex);
+        }
+        pthread_mutex_unlock(&earlysuspend_mutex);
+    }
+
     ALOGV("autosuspend_earlysuspend_enable done\n");
 
     return 0;
@@ -121,6 +146,14 @@ static int autosuspend_earlysuspend_disable(void)
         goto err;
     }
 
+    if (wait_for_earlysuspend) {
+        pthread_mutex_lock(&earlysuspend_mutex);
+        while (earlysuspend_state != EARLYSUSPEND_ON) {
+            pthread_cond_wait(&earlysuspend_cond, &earlysuspend_mutex);
+        }
+        pthread_mutex_unlock(&earlysuspend_mutex);
+    }
+
     ALOGV("autosuspend_earlysuspend_disable done\n");
 
     return 0;
@@ -149,12 +182,17 @@ void start_earlysuspend_thread(void)
         return;
     }
 
+    wait_for_fb_wake();
+
     ALOGI("Starting early suspend unblocker thread\n");
     ret = pthread_create(&earlysuspend_thread, NULL, earlysuspend_thread_func, NULL);
     if (ret) {
-        strerror_r(ret, buf, sizeof(buf));
+        strerror_r(errno, buf, sizeof(buf));
         ALOGE("Error creating thread: %s\n", buf);
+        return;
     }
+
+    wait_for_earlysuspend = true;
 }
 
 struct autosuspend_ops *autosuspend_earlysuspend_init(void)