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Diffstat (limited to 'drivers/usb/serial/generic.c')
-rw-r--r-- | drivers/usb/serial/generic.c | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/drivers/usb/serial/generic.c b/drivers/usb/serial/generic.c index 83443d6306d6..94b3c83b61cc 100644 --- a/drivers/usb/serial/generic.c +++ b/drivers/usb/serial/generic.c @@ -578,6 +578,26 @@ int usb_serial_handle_break(struct usb_serial_port *port) } EXPORT_SYMBOL_GPL(usb_serial_handle_break); +/** + * usb_serial_handle_dcd_change - handle a change of carrier detect state + * @port: usb_serial_port structure for the open port + * @tty: tty_struct structure for the port + * @status: new carrier detect status, nonzero if active + */ +void usb_serial_handle_dcd_change(struct usb_serial_port *usb_port, + struct tty_struct *tty, unsigned int status) +{ + struct tty_port *port = &usb_port->port; + + dbg("%s - port %d, status %d", __func__, usb_port->number, status); + + if (status) + wake_up_interruptible(&port->open_wait); + else if (tty && !C_CLOCAL(tty)) + tty_hangup(tty); +} +EXPORT_SYMBOL_GPL(usb_serial_handle_dcd_change); + int usb_serial_generic_resume(struct usb_serial *serial) { struct usb_serial_port *port; |