diff options
| author | Johan Hovold <johan@kernel.org> | 2020-11-16 17:18:21 +0100 |
|---|---|---|
| committer | Johan Hovold <johan@kernel.org> | 2020-12-04 14:57:20 +0100 |
| commit | 95168d624f3a8dee466525767200391a0fb006b9 (patch) | |
| tree | dd49ded172847fa86e1b85adc9d492a813ae2b35 /drivers/usb/serial/cp210x.c | |
| parent | USB: serial: mos7720: defer state restore to a workqueue (diff) | |
| download | linux-95168d624f3a8dee466525767200391a0fb006b9.tar.xz linux-95168d624f3a8dee466525767200391a0fb006b9.zip | |
USB: serial: cp210x: return early on unchanged termios
Return early from set_termios() in case no relevant terminal settings
have changed.
This avoids testing each parameter in turn and specifically allows the
line-control handling to be cleaned up further.
Signed-off-by: Johan Hovold <johan@kernel.org>
Diffstat (limited to 'drivers/usb/serial/cp210x.c')
| -rw-r--r-- | drivers/usb/serial/cp210x.c | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/drivers/usb/serial/cp210x.c b/drivers/usb/serial/cp210x.c index d0c05aa8a0d6..f1fd109d97d5 100644 --- a/drivers/usb/serial/cp210x.c +++ b/drivers/usb/serial/cp210x.c @@ -1352,6 +1352,15 @@ static void cp210x_disable_event_mode(struct usb_serial_port *port) port_priv->event_mode = false; } +static bool cp210x_termios_change(const struct ktermios *a, const struct ktermios *b) +{ + bool iflag_change; + + iflag_change = ((a->c_iflag ^ b->c_iflag) & INPCK); + + return tty_termios_hw_change(a, b) || iflag_change; +} + static void cp210x_set_termios(struct tty_struct *tty, struct usb_serial_port *port, struct ktermios *old_termios) { @@ -1359,6 +1368,9 @@ static void cp210x_set_termios(struct tty_struct *tty, unsigned int cflag, old_cflag; u16 bits; + if (!cp210x_termios_change(&tty->termios, old_termios)) + return; + cflag = tty->termios.c_cflag; old_cflag = old_termios->c_cflag; |