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| author | Johan Hovold <jhovold@gmail.com> | 2013-05-05 20:32:32 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-05-16 17:32:22 -0700 |
| commit | ff93b19eed0d5c124ee7168650a8e2e120ac8ea4 (patch) | |
| tree | 57151bdd9f8a28509f2feac7ac3755833395c1e5 /drivers/usb/serial/ti_usb_3410_5052.c | |
| parent | b16634adce951a7371be931487034f7365971ed0 (diff) | |
| download | linux-ff93b19eed0d5c124ee7168650a8e2e120ac8ea4.tar.gz | |
USB: ti_usb_3410_5052: fix chars_in_buffer overhead
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>
Diffstat (limited to 'drivers/usb/serial/ti_usb_3410_5052.c')
| -rw-r--r-- | drivers/usb/serial/ti_usb_3410_5052.c | 23 |
1 files changed, 15 insertions, 8 deletions
diff --git a/drivers/usb/serial/ti_usb_3410_5052.c b/drivers/usb/serial/ti_usb_3410_5052.c index cac47aef29189..c92c5ed4e580e 100644 --- a/drivers/usb/serial/ti_usb_3410_5052.c +++ b/drivers/usb/serial/ti_usb_3410_5052.c @@ -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) { |