USB: serial: ch341: fix resume after reset

Fix reset-resume handling which failed to resubmit the read and
interrupt URBs, thereby leaving a port that was open before suspend in a
broken state until closed and reopened.

Fixes: 1ded7ea47b88 ("USB: ch341 serial: fix port number changed after
resume")
Fixes: 2bfd1c96a9fb ("USB: serial: ch341: remove reset_resume callback")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>

diff --git a/drivers/usb/serial/ch341.c b/drivers/usb/serial/ch341.c
index 8f41d4385f1c6982b7b7057ddff3b400cc79b772..5343d65f3b52ce0abc77f73b07f36670b8bb6dbc 100644 (file)
--- a/drivers/usb/serial/ch341.c
+++ b/drivers/usb/serial/ch341.c
@@ -582,14 +582,23 @@ static int ch341_tiocmget(struct tty_struct *tty)
 
 static int ch341_reset_resume(struct usb_serial *serial)
 {
-       struct ch341_private *priv;
-
-       priv = usb_get_serial_port_data(serial->port[0]);
+       struct usb_serial_port *port = serial->port[0];
+       struct ch341_private *priv = usb_get_serial_port_data(port);
+       int ret;
 
        /* reconfigure ch341 serial port after bus-reset */
        ch341_configure(serial->dev, priv);
 
-       return 0;
+       if (tty_port_initialized(&port->port)) {
+               ret = usb_submit_urb(port->interrupt_in_urb, GFP_NOIO);
+               if (ret) {
+                       dev_err(&port->dev, "failed to submit interrupt urb: %d\n",
+                               ret);
+                       return ret;
+               }
+       }
+
+       return usb_serial_generic_resume(serial);
 }
 
 static struct usb_serial_driver ch341_device = {