Techwizz/kernel-fxtec-pro1x
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

USB: ti_usb_3410_5052: fix chars_in_buffer overhead

Browse source 
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 2c992cd73 ("USB:
ti_usb_3410_5052: 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 <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Johan Hovold 2013-05-05 20:32:32 +02:00 • committed by Greg Kroah-Hartman
parent b16634adce
commit ff93b19eed
1 changed files with 15 additions and 8 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

23
drivers/usb/serial/ti_usb_3410_5052.c
View file

@ -101,6 +101,7 @@ static int ti_write(struct tty_struct *tty, struct usb_serial_port *port,
const unsigned char *data, int count);
static int ti_write_room(struct tty_struct *tty);
static int ti_chars_in_buffer(struct tty_struct *tty);
static bool ti_tx_empty(struct usb_serial_port *port);
static void ti_throttle(struct tty_struct *tty);
static void ti_unthrottle(struct tty_struct *tty);
static int ti_ioctl(struct tty_struct *tty,
@ -222,6 +223,7 @@ static struct usb_serial_driver ti_1port_device = {
.write = ti_write,
.write_room = ti_write_room,
.chars_in_buffer = ti_chars_in_buffer,
.tx_empty = ti_tx_empty,
.throttle = ti_throttle,
.unthrottle = ti_unthrottle,
.ioctl = ti_ioctl,
@ -253,6 +255,7 @@ static struct usb_serial_driver ti_2port_device = {
.write = ti_write,
.write_room = ti_write_room,
.chars_in_buffer = ti_chars_in_buffer,
.tx_empty = ti_tx_empty,
.throttle = ti_throttle,
.unthrottle = ti_unthrottle,
.ioctl = ti_ioctl,
@ -684,8 +687,6 @@ static int ti_chars_in_buffer(struct tty_struct *tty)
struct ti_port *tport = usb_get_serial_port_data(port);
int chars = 0;
unsigned long flags;
int ret;
u8 lsr;
if (tport == NULL)
return 0;
@ -694,16 +695,22 @@ static int ti_chars_in_buffer(struct tty_struct *tty)
chars = kfifo_len(&tport->write_fifo);
spin_unlock_irqrestore(&tport->tp_lock, flags);
if (!chars) {
ret = ti_get_lsr(tport, &lsr);
if (!ret && !(lsr & TI_LSR_TX_EMPTY))
chars = 1;
}
dev_dbg(&port->dev, "%s - returns %d\n", __func__, chars);
return chars;
}
static bool ti_tx_empty(struct usb_serial_port *port)
{
struct ti_port *tport = usb_get_serial_port_data(port);
int ret;
u8 lsr;
ret = ti_get_lsr(tport, &lsr);
if (!ret && !(lsr & TI_LSR_TX_EMPTY))
return false;
return true;
}
static void ti_throttle(struct tty_struct *tty)
{