From 0693196fe7bbb5e6cafd255dfce91ff6d10bc18f Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Sun, 5 May 2013 20:32:27 +0200 Subject: [PATCH] USB: serial: add wait_until_sent operation Add wait_until_sent operation which can be used to wait for hardware buffers to drain. Signed-off-by: Johan Hovold Signed-off-by: Greg Kroah-Hartman --- drivers/usb/serial/usb-serial.c | 17 +++++++++++++++++ include/linux/usb/serial.h | 1 + 2 files changed, 18 insertions(+) diff --git a/drivers/usb/serial/usb-serial.c b/drivers/usb/serial/usb-serial.c index cf75beb1251b..31d27686151f 100644 --- a/drivers/usb/serial/usb-serial.c +++ b/drivers/usb/serial/usb-serial.c @@ -375,6 +375,22 @@ static int serial_chars_in_buffer(struct tty_struct *tty) return count; } +static void serial_wait_until_sent(struct tty_struct *tty, int timeout) +{ + struct usb_serial_port *port = tty->driver_data; + struct usb_serial *serial = port->serial; + + dev_dbg(tty->dev, "%s\n", __func__); + + if (!port->serial->type->wait_until_sent) + return; + + mutex_lock(&serial->disc_mutex); + if (!serial->disconnected) + port->serial->type->wait_until_sent(tty, timeout); + mutex_unlock(&serial->disc_mutex); +} + static void serial_throttle(struct tty_struct *tty) { struct usb_serial_port *port = tty->driver_data; @@ -1191,6 +1207,7 @@ static const struct tty_operations serial_ops = { .unthrottle = serial_unthrottle, .break_ctl = serial_break, .chars_in_buffer = serial_chars_in_buffer, + .wait_until_sent = serial_wait_until_sent, .tiocmget = serial_tiocmget, .tiocmset = serial_tiocmset, .get_icount = serial_get_icount, diff --git a/include/linux/usb/serial.h b/include/linux/usb/serial.h index b9b0f7b4e43b..afbb7eeaac5f 100644 --- a/include/linux/usb/serial.h +++ b/include/linux/usb/serial.h @@ -268,6 +268,7 @@ struct usb_serial_driver { struct usb_serial_port *port, struct ktermios *old); void (*break_ctl)(struct tty_struct *tty, int break_state); int (*chars_in_buffer)(struct tty_struct *tty); + void (*wait_until_sent)(struct tty_struct *tty, long timeout); void (*throttle)(struct tty_struct *tty); void (*unthrottle)(struct tty_struct *tty); int (*tiocmget)(struct tty_struct *tty);