Changeset 82798 in vbox for trunk/src/VBox/Devices/Serial

Timestamp:

Jan 20, 2020 3:35:50 PM (5 years ago)

Author:

vboxsync

svn:sync-xref-src-repo-rev:

135759

Message:

Devices/Serial: Some fixes for unconnected mode where the application inside the guest accessing the serial port could hang

Location:

trunk/src/VBox/Devices/Serial

Files:

• DrvChar.cpp (modified) (1 diff)
• UartCore.cpp (modified) (3 diffs)

trunk/src/VBox/Devices/Serial/DrvChar.cpp

@@ -192 +192 @@
 static DECLCALLBACK(int) drvCharQueryStsLines(PPDMISERIALCONNECTOR pInterface, uint32_t *pfStsLines)
 {
-    /* Nothing to do here. */
-    *pfStsLines = 0;
+    /* Always carrier detect, data set read and clear to send. */
+    *pfStsLines = PDMISERIALPORT_STS_LINE_DCD | PDMISERIALPORT_STS_LINE_DSR | PDMISERIALPORT_STS_LINE_CTS;
     RT_NOREF(pInterface);
     return VINF_SUCCESS;

trunk/src/VBox/Devices/Serial/UartCore.cpp

@@ -1122 +1122 @@
         }
         else if (pThisCC->pDrvSerial)
+        {
             pThisCC->pDrvSerial->pfnChgModemLines(pThisCC->pDrvSerial,
                                                   RT_BOOL(uVal & UART_REG_MCR_RTS),
                                                   RT_BOOL(uVal & UART_REG_MCR_DTR));
+
+            uint32_t fStsLines = 0;
+            int rc = pThisCC->pDrvSerial->pfnQueryStsLines(pThisCC->pDrvSerial, &fStsLines);
+            if (RT_SUCCESS(rc))
+                uartR3StsLinesUpdate(pDevIns, pThis, pThisCC, fStsLines);
+            else
+                LogRelMax(10, ("Serial#%d: Failed to query status line status with %Rrc during reset\n",
+                               pDevIns->iInstance, rc));
+        }
+        else /* Loopback mode got disabled and no driver attached, fake presence. */
+            uartR3MsrUpdate(pDevIns, pThis, pThisCC, UART_REG_MSR_DCD | UART_REG_MSR_CTS | UART_REG_MSR_DSR);
 #endif
     }
@@ -1549 +1561 @@
             ASMAtomicSubU32(&pThis->cbAvailRdr, 1);
     }
+
     if (cbRead == 1)
         PDMDevHlpTimerSetRelative(pDevIns, pThis->hTimerTxUnconnected, pThis->cSymbolXferTicks, NULL);
+    else
+    {
+        /* NO data left, set the transmitter holding register as empty. */
+        UART_REG_SET(pThis->uRegLsr, UART_REG_LSR_TEMT);
+    }
 
     PDMDevHlpCritSectLeave(pDevIns, &pThis->CritSect);
@@ -1884 +1902 @@
     pThis->uRegMcr        = 0;
     pThis->uRegLsr        = UART_REG_LSR_THRE | UART_REG_LSR_TEMT;
-    pThis->uRegMsr        = 0; /* Updated below. */
+    pThis->uRegMsr        = UART_REG_MSR_DCD | UART_REG_MSR_CTS | UART_REG_MSR_DSR | UART_REG_MSR_DCTS | UART_REG_MSR_DDSR | UART_REG_MSR_DDCD;
     pThis->uRegScr        = 0;
     pThis->fIrqCtiPending = false;