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>

diff --git a/drivers/usb/serial/ftdi_sio.c b/drivers/usb/serial/ftdi_sio.c
index ffc79ee..9979d49 100644 (file)
--- 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;
 }