We should check the flush_buffer method of a tty for null before invoking it. Some drivers such as usbserial don't implement flush_buffer. This will be required for upcoming patches where we expand spk_ttyio to support more than just ttyS*. Signed-off-by: Okash Khawaja <okash.khawaja@xxxxxxxxx> Reviewed-by: Samuel Thibault <samuel.thibault@xxxxxxxxxxxx> --- drivers/staging/speakup/spk_ttyio.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/staging/speakup/spk_ttyio.c +++ b/drivers/staging/speakup/spk_ttyio.c @@ -227,7 +227,8 @@ static unsigned char spk_ttyio_in_nowait static void spk_ttyio_flush_buffer(void) { - speakup_tty->ops->flush_buffer(speakup_tty); + if (speakup_tty->ops->flush_buffer) + speakup_tty->ops->flush_buffer(speakup_tty); } int spk_ttyio_synth_probe(struct spk_synth *synth) _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel