power: Keep boostpulse fd opened

No one else should be writing to this, so keep the fd
opened.

Change-Id: I4258f7f7d69250f4832a67807031ab3faa9ff586

power/power.c

@@ -62,7 +62,6 @@ enum power_profile_e {
 };
 
 static enum power_profile_e current_power_profile = PROFILE_BALANCED;
-static bool boostpulse_warned = false;
 
 /**********************************************************
  *** HELPER FUNCTIONS
@@ -140,29 +139,32 @@ static void boost(int32_t duration_us)
     close(fd);
 }
 
-/**********************************************************
- *** POWER FUNCTIONS
- **********************************************************/
+static void boostpulse_open(struct samsung_power_module *samsung_pwr)
+{
+    samsung_pwr->boostpulse_fd = open(BOOSTPULSE_PATH, O_WRONLY);
+    if (samsung_pwr->boostpulse_fd < 0) {
+        ALOGE("Error opening %s: %s\n", BOOSTPULSE_PATH, strerror(errno));
+    }
+}
 
-/* You need to request the powerhal lock before calling this function */
-static int boostpulse_open(struct samsung_power_module *samsung_pwr)
+static void send_boostpulse(int boostpulse_fd)
 {
-    char errno_str[64];
+    int len;
 
-    if (samsung_pwr->boostpulse_fd < 0) {
-        samsung_pwr->boostpulse_fd = open(BOOSTPULSE_PATH, O_WRONLY);
-        if (samsung_pwr->boostpulse_fd < 0) {
-            if (!boostpulse_warned) {
-                strerror_r(errno, errno_str, sizeof(errno_str));
-                ALOGE("Error opening %s: %s", BOOSTPULSE_PATH, errno_str);
-                boostpulse_warned = true;
-            }
-        }
+    if (boostpulse_fd < 0) {
+        return;
     }
 
-    return samsung_pwr->boostpulse_fd;
+    len = write(boostpulse_fd, "1", 1);
+    if (len < 0) {
+        ALOGE("Error writing to %s: %s", BOOSTPULSE_PATH, strerror(errno));
+    }
 }
 
+/**********************************************************
+ *** POWER FUNCTIONS
+ **********************************************************/
+
 static void set_power_profile(struct samsung_power_module *samsung_pwr,
                               int profile)
 {
@@ -413,16 +415,7 @@ static void samsung_power_hint(struct power_module *module,
             }
 
             ALOGV("%s: POWER_HINT_INTERACTION", __func__);
-
-            if (boostpulse_open(samsung_pwr) >= 0) {
-                len = write(samsung_pwr->boostpulse_fd, "1", 1);
-
-                if (len < 0) {
-                    strerror_r(errno, errno_str, sizeof(errno_str));
-                    ALOGE("Error writing to %s: %s", BOOSTPULSE_PATH, errno_str);
-                }
-            }
-
+            send_boostpulse(samsung_pwr->boostpulse_fd);
             break;
         }
         case POWER_HINT_VSYNC: {