2 files changed, 2 insertions, 0 deletions

diff --git a/drivers/usb/serial/mos7840.c b/drivers/usb/serial/mos7840.c
index aeeb9cb20999..0b29c5383dc8 100644
--- a/drivers/usb/serial/mos7840.c
+++ b/drivers/usb/serial/mos7840.c
@@ -1722,6 +1722,7 @@ static int mos7840_tiocmset(struct usb_serial_port *port, struct file *file,
         if (mos7840_port == NULL)
                 return -ENODEV;
 
+        /* FIXME: What locks the port registers ? */
         mcr = mos7840_port->shadowMCR;
         if (clear & TIOCM_RTS)
                 mcr &= ~MCR_RTS;
diff --git a/drivers/usb/serial/option.c b/drivers/usb/serial/option.c
index d101025a4c63..0e7eeb2820e2 100644
--- a/drivers/usb/serial/option.c
+++ b/drivers/usb/serial/option.c
@@ -458,6 +458,7 @@ static int option_tiocmset(struct usb_serial_port *port, struct file *file,
 
         portdata = usb_get_serial_port_data(port);
 
+        /* FIXME: what locks portdata fields ? */
         if (set & TIOCM_RTS)
                 portdata->rts_state = 1;
         if (set & TIOCM_DTR)