diff --git a/src/add-ons/kernel/drivers/ports/usb_serial/Driver.cpp b/src/add-ons/kernel/drivers/ports/usb_serial/Driver.cpp
index f146e479f2..1c8b0cfc26 100644
--- a/src/add-ons/kernel/drivers/ports/usb_serial/Driver.cpp
+++ b/src/add-ons/kernel/drivers/ports/usb_serial/Driver.cpp
@@ -43,13 +43,14 @@ usb_serial_device_added(usb_device device, void **cookie)
 	const usb_configuration_info *configuration;
 	for (int i = 0; i < descriptor->num_configurations; i++) {
 		configuration = gUSBModule->get_nth_configuration(device, i);
-		if (!configuration)
+		if (configuration == NULL)
 			continue;
 
 		status = serialDevice->AddDevice(configuration);
-		if (status == B_OK)
+		if (status == B_OK) {
 			// Found!
 			break;
+		}
 	}
 
 	if (status < B_OK) {
diff --git a/src/add-ons/kernel/drivers/ports/usb_serial/Prolific.cpp b/src/add-ons/kernel/drivers/ports/usb_serial/Prolific.cpp
index 659008cb47..fde76b4ee7 100644
--- a/src/add-ons/kernel/drivers/ports/usb_serial/Prolific.cpp
+++ b/src/add-ons/kernel/drivers/ports/usb_serial/Prolific.cpp
@@ -117,6 +117,9 @@ ProlificDevice::SendRequestList(request_item *list, size_t length)
 			list[i].out ? NULL : buffer,
 			&bufferLength);
 		TRACE(" ProlificDevice::SendRequestList(): request[%d]: 0x%08lx\n", i, status);
+		if (status != B_OK) {
+			TRACE_ALWAYS("sending request list failed:0x%08lx\n", status);
+		}
 	}
 
 	return B_OK;
diff --git a/src/add-ons/kernel/drivers/ports/usb_serial/Tracing.cpp b/src/add-ons/kernel/drivers/ports/usb_serial/Tracing.cpp
index 95d1823857..e4d36ff1f4 100644
--- a/src/add-ons/kernel/drivers/ports/usb_serial/Tracing.cpp
+++ b/src/add-ons/kernel/drivers/ports/usb_serial/Tracing.cpp
@@ -18,7 +18,7 @@
 #if DEBUG
 bool gLogEnabled = true;
 #else
-bool gLogEnabled = true;
+bool gLogEnabled = false;
 #endif
 
 bool gLogToFile = false;
@@ -108,12 +108,12 @@ trace_termios(struct termios *tios)
 		"\tc_cflag:  0x%08x\n"
 		"\tc_lflag:  0x%08x\n"
 		"\tc_line:   0x%08x\n"
-//		"\tc_ixxxxx: 0x%08x\n"
-//		"\tc_oxxxxx: 0x%08x\n"
+		"\tc_ispeed: 0x%08x\n"
+		"\tc_ospeed: 0x%08x\n"
 		"\tc_cc[0x%02x, 0x%02x, 0x%02x, 0x%02x, 0x%02x, 0x%02x, 0x%02x, 0x%02x, 0x%02x, 0x%02x, 0x%02x]\n",
 		tios->c_iflag, tios->c_oflag, tios->c_cflag, tios->c_lflag,
 		tios->c_line,
-//		tios->c_ixxxxx, tios->c_oxxxxx,
+		tios->c_ispeed, tios->c_ospeed,
 		tios->c_cc[0], tios->c_cc[1], tios->c_cc[2], tios->c_cc[3],
 		tios->c_cc[4], tios->c_cc[5], tios->c_cc[6], tios->c_cc[7],
 		tios->c_cc[8], tios->c_cc[9], tios->c_cc[10]);