USB: ftdi_sio: fix initialisation of latency timeout

Latency timeout was read but never stored on port probe. When
ASYNC_LOW_LATENCY was cleared the device timeout would get set to 0
rather than the default 16ms.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 5 insertions, 4 deletions

diff --git a/drivers/usb/serial/ftdi_sio.c b/drivers/usb/serial/ftdi_sio.c
index ffc79eea963d..9979d4920a32 100644
--- a/drivers/usb/serial/ftdi_sio.c
+++ b/drivers/usb/serial/ftdi_sio.c
@@ -1184,7 +1184,6 @@ static int read_latency_timer(struct usb_serial_port *port)
         unsigned short latency = 0;
         int rv = 0;
 
-
         dbg("%s", __func__);
 
         rv = usb_control_msg(udev,
@@ -1197,8 +1196,9 @@ static int read_latency_timer(struct usb_serial_port *port)
         if (rv < 0) {
                 dev_err(&port->dev, "Unable to read latency timer: %i\n", rv);
                 return -EIO;
-        }
-        return latency;
+        } else
+                priv->latency = latency;
+        return rv;
 }
 
 static int get_serial_info(struct usb_serial_port *port,
@@ -1584,7 +1584,8 @@ static int ftdi_sio_port_probe(struct usb_serial_port *port)
 
         ftdi_determine_type(port);
         ftdi_set_max_packet_size(port);
-        read_latency_timer(port);
+        if (read_latency_timer(port) < 0)
+                priv->latency = 16;
         create_sysfs_attrs(port);
         return 0;
 }