From 11f2c8879565cd891881726d1f754072541ed28e Mon Sep 17 00:00:00 2001
From: Jimmy Hu <hhhuuu@google.com>
Date: Mon, 23 May 2022 04:29:06 +0000
Subject: [PATCH] Write the pullup value only if new value applied

Bug: 226018845
Test: build, boot
Signed-off-by: Jimmy Hu <hhhuuu@google.com>
Change-Id: I64a964753fc89a29d278f1c426b2746abc2a2b12
---
 usb/usb/Usb.cpp | 31 +++++++++++++++++++++----------
 1 file changed, 21 insertions(+), 10 deletions(-)

diff --git a/usb/usb/Usb.cpp b/usb/usb/Usb.cpp
index b8ad7c5f..6cff2f26 100644
--- a/usb/usb/Usb.cpp
+++ b/usb/usb/Usb.cpp
@@ -83,23 +83,39 @@ ScopedAStatus Usb::enableUsbData(const string& in_portName, bool in_enable,
         int64_t in_transactionId) {
     bool result = true;
     std::vector<PortStatus> currentPortStatus;
+    string pullup;
 
     ALOGI("Userspace turn %s USB data signaling. opID:%ld", in_enable ? "on" : "off",
             in_transactionId);
 
     if (in_enable) {
         if (!mUsbDataEnabled) {
+            if (ReadFileToString(PULLUP_PATH, &pullup)) {
+                pullup = Trim(pullup);
+                if (pullup != kGadgetName) {
+                    if (!WriteStringToFile(kGadgetName, PULLUP_PATH)) {
+                        ALOGE("Gadget cannot be pulled up");
+                        result = false;
+                    }
+                }
+            }
+
             if (!WriteStringToFile("1", USB_DATA_PATH)) {
                 ALOGE("Not able to turn on usb connection notification");
                 result = false;
             }
-
-            if (!WriteStringToFile(kGadgetName, PULLUP_PATH)) {
-                ALOGE("Gadget cannot be pulled up");
-                result = false;
-            }
         }
     } else {
+        if (ReadFileToString(PULLUP_PATH, &pullup)) {
+            pullup = Trim(pullup);
+            if (pullup == kGadgetName) {
+                if (!WriteStringToFile("none", PULLUP_PATH)) {
+                    ALOGE("Gadget cannot be pulled down");
+                    result = false;
+                }
+            }
+        }
+
         if (!WriteStringToFile("1", ID_PATH)) {
             ALOGE("Not able to turn off host mode");
             result = false;
@@ -114,11 +130,6 @@ ScopedAStatus Usb::enableUsbData(const string& in_portName, bool in_enable,
             ALOGE("Not able to turn on usb connection notification");
             result = false;
         }
-
-        if (!WriteStringToFile("none", PULLUP_PATH)) {
-            ALOGE("Gadget cannot be pulled down");
-            result = false;
-        }
     }
 
     if (result) {