From: Don Slutz <dslutz@verizon.com> Date: Tue, 18 Mar 2014 12:29:34 -0400 Subject: [PATCH] char/serial: Fix emptyness handling The commit 88c1ee73d3231c74ff90bcfc084a7589670ec244 char/serial: Fix emptyness check Still causes extra NULL byte(s) to be sent. So if the fifo is empty, do not send an extra NULL byte. Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com> Signed-off-by: Don Slutz <dslutz@verizon.com> Message-id: 1395160174-16006-1-git-send-email-dslutz@verizon.com Signed-off-by: Peter Maydell <peter.maydell@linaro.org> (cherry picked from commit dffacd4654ec8bf2898aed230852154c6ed755ed) --- hw/char/serial.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/hw/char/serial.c b/hw/char/serial.c index 2989ca2..6d10747 100644 --- a/hw/char/serial.c +++ b/hw/char/serial.c @@ -224,8 +224,10 @@ static gboolean serial_xmit(GIOChannel *chan, GIOCondition cond, void *opaque) if (s->tsr_retry <= 0) { if (s->fcr & UART_FCR_FE) { - s->tsr = fifo8_is_empty(&s->xmit_fifo) ? - 0 : fifo8_pop(&s->xmit_fifo); + if (fifo8_is_empty(&s->xmit_fifo)) { + return FALSE; + } + s->tsr = fifo8_pop(&s->xmit_fifo); if (!s->xmit_fifo.num) { s->lsr |= UART_LSR_THRE; }