From a22b308d42f721b09fa3d4f50c3ba9c456fe62a0 Mon Sep 17 00:00:00 2001
From: Kyle Tso <kyletso@google.com>
Date: Wed, 12 Jun 2024 17:14:02 +0800
Subject: [PATCH 1/2] usb: Add retry on role switch

Bug: 341996696
Change-Id: I8caa65288af1588d24fea4aa6c5768d45d69bbd5
Signed-off-by: Kyle Tso <kyletso@google.com>
(cherry picked from commit ef5856a4474002cc35a51377adffddd4cb239796)
---
 usb/usb/Usb.cpp | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/usb/usb/Usb.cpp b/usb/usb/Usb.cpp
index 4bdd5ed..1a03917 100644
--- a/usb/usb/Usb.cpp
+++ b/usb/usb/Usb.cpp
@@ -672,6 +672,10 @@ ScopedAStatus Usb::switchRole(const string& in_portName, const PortRole& in_role
         fp = fopen(filename.c_str(), "w");
         if (fp != NULL) {
             int ret = fputs(convertRoletoString(in_role).c_str(), fp);
+            if (ret == EAGAIN) {
+                std::this_thread::sleep_for(std::chrono::milliseconds(700));
+                ret = fputs(convertRoletoString(in_role).c_str(), fp);
+            }
             fclose(fp);
             if ((ret != EOF) && ReadFileToString(filename, &written)) {
                 written = Trim(written);

From 4f43c1cdaf294cc3dc0d654113733ddc5e0582e9 Mon Sep 17 00:00:00 2001
From: Kyle Tso <kyletso@google.com>
Date: Thu, 13 Jun 2024 16:54:37 +0800
Subject: [PATCH 2/2] usb: Log for retry on role switch

Add a log for the retry. Also define the sleep time in the header file.

Bug: 341996696
Change-Id: Ib3cc0c6ad576e7cda26b7f50cdc61d52e6349c78
Signed-off-by: Kyle Tso <kyletso@google.com>
(cherry picked from commit d17fdff5f81cff76adaa75d50f26318be8048123)
---
 usb/usb/Usb.cpp | 3 ++-
 usb/usb/Usb.h   | 1 +
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/usb/usb/Usb.cpp b/usb/usb/Usb.cpp
index 1a03917..d8afb80 100644
--- a/usb/usb/Usb.cpp
+++ b/usb/usb/Usb.cpp
@@ -673,7 +673,8 @@ ScopedAStatus Usb::switchRole(const string& in_portName, const PortRole& in_role
         if (fp != NULL) {
             int ret = fputs(convertRoletoString(in_role).c_str(), fp);
             if (ret == EAGAIN) {
-                std::this_thread::sleep_for(std::chrono::milliseconds(700));
+                ALOGI("role switch busy, retry in %d ms", ROLE_SWAP_RETRY_MS);
+                std::this_thread::sleep_for(std::chrono::milliseconds(ROLE_SWAP_RETRY_MS));
                 ret = fputs(convertRoletoString(in_role).c_str(), fp);
             }
             fclose(fp);
diff --git a/usb/usb/Usb.h b/usb/usb/Usb.h
index 96af846..8f0c3a0 100644
--- a/usb/usb/Usb.h
+++ b/usb/usb/Usb.h
@@ -80,6 +80,7 @@ constexpr char kGadgetName[] = "11210000.dwc3";
 #define DISPLAYPORT_IRQ_HPD_COUNT_CHECK 3
 
 #define DISPLAYPORT_POLL_WAIT_MS 100
+#define ROLE_SWAP_RETRY_MS 700
 
 #define SVID_DISPLAYPORT "ff01"
 #define SVID_THUNDERBOLT "8087"