From 833efc0ed19ce9ed7a84dfd3684eb9d892fe9ded Mon Sep 17 00:00:00 2001 From: Paul Chavent Date: Mon, 16 Sep 2013 08:41:00 +0200 Subject: USB: serial: invoke dcd_change ldisc's handler. The DCD pin of the serial port can receive a PPS signal. By calling the port line discipline dcd handle, this patch allow to monitor PPS through USB serial devices. However the performance aren't as good as the uart drivers, so document this point too. Signed-off-by: Paul Chavent Acked-by: Rodolfo Giometti Signed-off-by: Greg Kroah-Hartman --- drivers/usb/serial/generic.c | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'drivers/usb/serial') diff --git a/drivers/usb/serial/generic.c b/drivers/usb/serial/generic.c index 1f31e6b..3a5dac8 100644 --- a/drivers/usb/serial/generic.c +++ b/drivers/usb/serial/generic.c @@ -570,6 +570,16 @@ void usb_serial_handle_dcd_change(struct usb_serial_port *usb_port, dev_dbg(&usb_port->dev, "%s - status %d\n", __func__, status); + if (tty) { + struct tty_ldisc *ld = tty_ldisc_ref(tty); + + if (ld) { + if (ld->ops->dcd_change) + ld->ops->dcd_change(tty, status); + tty_ldisc_deref(ld); + } + } + if (status) wake_up_interruptible(&port->open_wait); else if (tty && !C_CLOCAL(tty)) -- cgit v1.1