From 0cbb8c818c051fc5a9aaa8327954e901f6b8a745 Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Sun, 5 May 2013 20:32:31 +0200 Subject: USB: io_ti: fix chars_in_buffer overhead commit b16634adce951a7371be931487034f7365971ed0 upstream. Use the new generic usb-serial wait_until_sent implementation to wait for hardware buffers to drain. This removes the need to check the hardware buffers in chars_in_buffer and thus removes the overhead introduced by commit 263e1f9f ("USB: io_ti: query hardware-buffer status in chars_in_buffer") without breaking tty_wait_until_sent (used by, for example, tcdrain, tcsendbreak and close). Signed-off-by: Johan Hovold Signed-off-by: Greg Kroah-Hartman --- drivers/usb/serial/io_ti.c | 22 ++++++++++++++-------- 1 file changed, 14 insertions(+), 8 deletions(-) diff --git a/drivers/usb/serial/io_ti.c b/drivers/usb/serial/io_ti.c index 38f2489b289..f26decda9f2 100644 --- a/drivers/usb/serial/io_ti.c +++ b/drivers/usb/serial/io_ti.c @@ -2033,8 +2033,6 @@ static int edge_chars_in_buffer(struct tty_struct *tty) struct edgeport_port *edge_port = usb_get_serial_port_data(port); int chars = 0; unsigned long flags; - int ret; - if (edge_port == NULL) return 0; @@ -2042,16 +2040,22 @@ static int edge_chars_in_buffer(struct tty_struct *tty) chars = kfifo_len(&edge_port->write_fifo); spin_unlock_irqrestore(&edge_port->ep_lock, flags); - if (!chars) { - ret = tx_active(edge_port); - if (ret > 0) - chars = ret; - } - dev_dbg(&port->dev, "%s - returns %d\n", __func__, chars); return chars; } +static bool edge_tx_empty(struct usb_serial_port *port) +{ + struct edgeport_port *edge_port = usb_get_serial_port_data(port); + int ret; + + ret = tx_active(edge_port); + if (ret > 0) + return false; + + return true; +} + static void edge_throttle(struct tty_struct *tty) { struct usb_serial_port *port = tty->driver_data; @@ -2622,6 +2626,7 @@ static struct usb_serial_driver edgeport_1port_device = { .write = edge_write, .write_room = edge_write_room, .chars_in_buffer = edge_chars_in_buffer, + .tx_empty = edge_tx_empty, .break_ctl = edge_break, .read_int_callback = edge_interrupt_callback, .read_bulk_callback = edge_bulk_in_callback, @@ -2653,6 +2658,7 @@ static struct usb_serial_driver edgeport_2port_device = { .write = edge_write, .write_room = edge_write_room, .chars_in_buffer = edge_chars_in_buffer, + .tx_empty = edge_tx_empty, .break_ctl = edge_break, .read_int_callback = edge_interrupt_callback, .read_bulk_callback = edge_bulk_in_callback, -- cgit v1.2.3