USB: serial: metro-usb: dummy implement write_int_callback() function.

This function is never called now. Because we don`t send much data
to the device, only one byte via usb_interrupt_msg(). That doesn't require
callback function. But without declaration of write_int_callback inside
the struct usb_serial_driver, the usb_serial_probe doesn't initialize
endpoint address for the interrupt out pipe(interrupt_out_endpointAddress).
This endpoint is necessary for sending data via usb_interrupt_msg()
function.

Signed-off-by: Aleksey Babahin <tamerlan311@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 9 insertions, 0 deletions

diff --git a/drivers/usb/serial/metro-usb.c b/drivers/usb/serial/metro-usb.c
index 08d16e8c002d..92b6f85ab4b9 100644
--- a/drivers/usb/serial/metro-usb.c
+++ b/drivers/usb/serial/metro-usb.c
@@ -136,6 +136,14 @@ exit:
                         __func__, result);
 }
 
+static void metrousb_write_int_callback(struct urb *urb)
+{
+        struct usb_serial_port *port = urb->context;
+
+        dev_warn(&port->dev, "%s not implemented yet.\n",
+                __func__);
+}
+
 static void metrousb_cleanup(struct usb_serial_port *port)
 {
         dev_dbg(&port->dev, "%s\n", __func__);
@@ -377,6 +385,7 @@ static struct usb_serial_driver metrousb_device = {
         .open                   = metrousb_open,
         .close                  = metrousb_cleanup,
         .read_int_callback      = metrousb_read_int_callback,
+        .write_int_callback     = metrousb_write_int_callback,
         .attach                 = metrousb_startup,
         .release                = metrousb_shutdown,
         .throttle               = metrousb_throttle,