From 086158525b1ac340bcebb750761684dd27e6009e Mon Sep 17 00:00:00 2001
From: Robert Fisk <robert_fisk@fastmail.fm>
Date: Tue, 17 Apr 2018 01:22:08 +1200
Subject: [PATCH] Ignore mass storage commands after receiving SCSI stop/eject

---
 Upstream/Inc/upstream_msc.h                   |  2 +-
 Upstream/Inc/upstream_statemachine.h          |  2 ++
 .../Class/MSC/Src/usbd_msc.c                  |  9 +++----
 .../Class/MSC/Src/usbd_msc_scsi.c             |  1 +
 Upstream/Src/upstream_msc.c                   | 10 ++++++-
 Upstream/Src/upstream_statemachine.c          | 27 ++++++++++++++-----
 6 files changed, 38 insertions(+), 13 deletions(-)

diff --git a/Upstream/Inc/upstream_msc.h b/Upstream/Inc/upstream_msc.h
index e8fd33a..4ef8ba0 100644
--- a/Upstream/Inc/upstream_msc.h
+++ b/Upstream/Inc/upstream_msc.h
@@ -36,7 +36,7 @@ HAL_StatusTypeDef Upstream_MSC_BeginWrite(UpstreamMSCCallbackTypeDef callback,
                                           uint32_t writeBlockCount);
 HAL_StatusTypeDef Upstream_MSC_PutStreamDataPacket(UpstreamPacketTypeDef* packetToSend,
                                                    uint32_t dataLength8);
-
+void              Upstream_MSC_RegisterDisconnect(void);
 
 
 #endif /* INC_UPSTREAM_MSC_H_ */
diff --git a/Upstream/Inc/upstream_statemachine.h b/Upstream/Inc/upstream_statemachine.h
index e6b982b..c021111 100644
--- a/Upstream/Inc/upstream_statemachine.h
+++ b/Upstream/Inc/upstream_statemachine.h
@@ -24,6 +24,7 @@ typedef enum
     STATE_WAIT_DEVICE,
     STATE_DEVICE_ACTIVE,
     STATE_SUSPENDED,
+    STATE_DISCONNECTING,
     STATE_ERROR
 } UpstreamStateTypeDef;
 
@@ -46,6 +47,7 @@ void Upstream_StateMachine_DeviceDisconnected(void);
 void Upstream_StateMachine_Suspend(void);
 void Upstream_StateMachine_CheckResume(void);
 void Upstream_StateMachine_Wakeup(void);
+void Upstream_StateMachine_RegisterDisconnect(void);
 
 
 
diff --git a/Upstream/Middlewares/ST/STM32_USB_Device_Library/Class/MSC/Src/usbd_msc.c b/Upstream/Middlewares/ST/STM32_USB_Device_Library/Class/MSC/Src/usbd_msc.c
index b1c1b3a..45ebf0e 100755
--- a/Upstream/Middlewares/ST/STM32_USB_Device_Library/Class/MSC/Src/usbd_msc.c
+++ b/Upstream/Middlewares/ST/STM32_USB_Device_Library/Class/MSC/Src/usbd_msc.c
@@ -379,13 +379,12 @@ uint8_t  USBD_MSC_DeInit (USBD_HandleTypeDef *pdev,
   USBD_LL_CloseEP(pdev,
                   MSC_EPIN_ADDR);
   
-  
-    /* De-Init the BOT layer */
-  MSC_BOT_DeInit(pdev);
-  
-  /* Free MSC Class Resources */
   if(pdev->pClassData != NULL)
   {
+    /* De-Init the BOT layer */
+    MSC_BOT_DeInit(pdev);
+  
+    /* Free MSC Class Resources */
     USBD_free(pdev->pClassData);
     pdev->pClassData  = NULL; 
   }
diff --git a/Upstream/Middlewares/ST/STM32_USB_Device_Library/Class/MSC/Src/usbd_msc_scsi.c b/Upstream/Middlewares/ST/STM32_USB_Device_Library/Class/MSC/Src/usbd_msc_scsi.c
index e2d8013..9c21762 100755
--- a/Upstream/Middlewares/ST/STM32_USB_Device_Library/Class/MSC/Src/usbd_msc_scsi.c
+++ b/Upstream/Middlewares/ST/STM32_USB_Device_Library/Class/MSC/Src/usbd_msc_scsi.c
@@ -550,6 +550,7 @@ static void SCSI_StartStopUnit(void)
     if ((SCSI_ProcessCmd_params[4] & START_STOP_DATA_MASK) == START_STOP_DATA_EJECT_STOP_MOTOR)
     {
         USBD_RequestStop(SCSI_ProcessCmd_pdev);               //Host is signalling us to disconnect
+        Upstream_MSC_RegisterDisconnect();
     }
 
   SCSI_ProcessCmd_hmsc->bot_data_length = 0;
diff --git a/Upstream/Src/upstream_msc.c b/Upstream/Src/upstream_msc.c
index a76997b..8e05a5e 100644
--- a/Upstream/Src/upstream_msc.c
+++ b/Upstream/Src/upstream_msc.c
@@ -369,7 +369,15 @@ HAL_StatusTypeDef Upstream_MSC_PutStreamDataPacket(UpstreamPacketTypeDef* packet
     packetToSend->Command = COMMAND_MSC_WRITE;
     return Upstream_TransmitPacket(packetToSend);
 }
-#endif
+#endif  //#ifdef CONFIG_MASS_STORAGE_WRITES_PERMITTED
+
+
+
+void Upstream_MSC_RegisterDisconnect(void)
+{
+    Upstream_StateMachine_RegisterDisconnect();
+}
+
 
 #endif  //#ifdef CONFIG_MASS_STORAGE_ENABLED
 
diff --git a/Upstream/Src/upstream_statemachine.c b/Upstream/Src/upstream_statemachine.c
index 37debfe..39794e7 100644
--- a/Upstream/Src/upstream_statemachine.c
+++ b/Upstream/Src/upstream_statemachine.c
@@ -79,19 +79,21 @@ void Upstream_StateMachine_SetErrorState(void)
 
 InterfaceCommandClassTypeDef Upstream_StateMachine_CheckActiveClass(void)
 {
-    if (UpstreamState == STATE_ERROR)
+    if ((UpstreamState == STATE_ERROR) ||
+        (UpstreamState == STATE_DISCONNECTING))
     {
         return COMMAND_CLASS_ERROR;
     }
 
-    if ((UpstreamState != STATE_DEVICE_ACTIVE) &&
-        (UpstreamState != STATE_SUSPENDED))
+    if ((UpstreamState == STATE_DEVICE_ACTIVE) ||
+        (UpstreamState == STATE_SUSPENDED))
     {
-        UPSTREAM_STATEMACHINE_FREAKOUT;
-        return COMMAND_CLASS_INTERFACE;
+        return ConfiguredDeviceClass;
     }
 
-    return ConfiguredDeviceClass;
+    //else:
+    UPSTREAM_STATEMACHINE_FREAKOUT;
+    return COMMAND_CLASS_INTERFACE;
 }
 
 
@@ -293,3 +295,16 @@ void Upstream_StateMachine_Wakeup(void)
     USBD_Start(&hUsbDeviceFS);
 }
 
+
+//Host sends a SCSI motor stop command, so we shouldn't process any more commands.
+void Upstream_StateMachine_RegisterDisconnect(void)
+{
+    if ((UpstreamState != STATE_DEVICE_ACTIVE) &&
+        (UpstreamState != STATE_SUSPENDED))
+    {
+        UPSTREAM_STATEMACHINE_FREAKOUT;
+        return;
+    }
+
+    UpstreamState = STATE_DISCONNECTING;
+}