+}
+
+static int ch341_tiocmset(struct usb_serial_port *port, struct file *file,
+ unsigned int set, unsigned int clear)
+{
+ struct ch341_private *priv = usb_get_serial_port_data(port);
+ unsigned long flags;
+ u8 control;
+
+ spin_lock_irqsave(&priv->lock, flags);
+ if (set & TIOCM_RTS)
+ priv->line_control |= CH341_BIT_RTS;
+ if (set & TIOCM_DTR)
+ priv->line_control |= CH341_BIT_DTR;
+ if (clear & TIOCM_RTS)
+ priv->line_control &= ~CH341_BIT_RTS;
+ if (clear & TIOCM_DTR)
+ priv->line_control &= ~CH341_BIT_DTR;
+ control = priv->line_control;
+ spin_unlock_irqrestore(&priv->lock, flags);
+
+ return ch341_set_handshake(port->serial->dev, control);
+}
+
+static void ch341_read_int_callback(struct urb *urb)
+{
+ struct usb_serial_port *port = (struct usb_serial_port *) urb->context;
+ unsigned char *data = urb->transfer_buffer;
+ unsigned int actual_length = urb->actual_length;
+ int status;
+
+ dbg("%s (%d)", __func__, port->number);
+
+ switch (urb->status) {
+ case 0:
+ /* success */
+ break;
+ case -ECONNRESET:
+ case -ENOENT:
+ case -ESHUTDOWN:
+ /* this urb is terminated, clean up */
+ dbg("%s - urb shutting down with status: %d", __func__,
+ urb->status);
+ return;
+ default:
+ dbg("%s - nonzero urb status received: %d", __func__,
+ urb->status);
+ goto exit;
+ }
+
+ usb_serial_debug_data(debug, &port->dev, __func__,
+ urb->actual_length, urb->transfer_buffer);
+
+ if (actual_length >= 4) {
+ struct ch341_private *priv = usb_get_serial_port_data(port);
+ unsigned long flags;
+
+ spin_lock_irqsave(&priv->lock, flags);
+ priv->line_status = (~(data[2])) & CH341_BITS_MODEM_STAT;
+ if ((data[1] & CH341_MULT_STAT))
+ priv->multi_status_change = 1;
+ spin_unlock_irqrestore(&priv->lock, flags);
+ wake_up_interruptible(&priv->delta_msr_wait);
+ }
+
+exit:
+ status = usb_submit_urb(urb, GFP_ATOMIC);
+ if (status)
+ dev_err(&urb->dev->dev,
+ "%s - usb_submit_urb failed with result %d\n",
+ __func__, status);
+}
+
+static int wait_modem_info(struct usb_serial_port *port, unsigned int arg)
+{
+ struct ch341_private *priv = usb_get_serial_port_data(port);
+ unsigned long flags;
+ u8 prevstatus;
+ u8 status;
+ u8 changed;
+ u8 multi_change = 0;
+
+ spin_lock_irqsave(&priv->lock, flags);
+ prevstatus = priv->line_status;
+ priv->multi_status_change = 0;
+ spin_unlock_irqrestore(&priv->lock, flags);
+
+ while (!multi_change) {
+ interruptible_sleep_on(&priv->delta_msr_wait);
+ /* see if a signal did it */
+ if (signal_pending(current))
+ return -ERESTARTSYS;
+
+ spin_lock_irqsave(&priv->lock, flags);
+ status = priv->line_status;
+ multi_change = priv->multi_status_change;
+ spin_unlock_irqrestore(&priv->lock, flags);
+
+ changed = prevstatus ^ status;
+
+ if (((arg & TIOCM_RNG) && (changed & CH341_BIT_RI)) ||
+ ((arg & TIOCM_DSR) && (changed & CH341_BIT_DSR)) ||
+ ((arg & TIOCM_CD) && (changed & CH341_BIT_DCD)) ||
+ ((arg & TIOCM_CTS) && (changed & CH341_BIT_CTS))) {
+ return 0;
+ }
+ prevstatus = status;
+ }
+
+ return 0;
+}
+
+static int ch341_ioctl(struct usb_serial_port *port, struct file *file,
+ unsigned int cmd, unsigned long arg)
+{
+ dbg("%s (%d) cmd = 0x%04x", __func__, port->number, cmd);
+
+ switch (cmd) {
+ case TIOCMIWAIT:
+ dbg("%s (%d) TIOCMIWAIT", __func__, port->number);
+ return wait_modem_info(port, arg);
+
+ default:
+ dbg("%s not supported = 0x%04x", __func__, cmd);
+ break;
+ }