From mboxrd@z Thu Jan 1 00:00:00 1970 From: soren.brinkmann@xilinx.com (Soren Brinkmann) Date: Tue, 3 Nov 2015 16:20:44 -0800 Subject: [PATCH 3/9] tty: xuartps: Always enable transmitter in start_tx In-Reply-To: <1446596450-20918-1-git-send-email-soren.brinkmann@xilinx.com> References: <1446596450-20918-1-git-send-email-soren.brinkmann@xilinx.com> Message-ID: <1446596450-20918-4-git-send-email-soren.brinkmann@xilinx.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org start_tx must start transmitting characters. Regardless of the state of the circular buffer, always enable the transmitter hardware. Signed-off-by: Soren Brinkmann --- drivers/tty/serial/xilinx_uartps.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/tty/serial/xilinx_uartps.c b/drivers/tty/serial/xilinx_uartps.c index dc1987f3dc0a..5edd1efca015 100644 --- a/drivers/tty/serial/xilinx_uartps.c +++ b/drivers/tty/serial/xilinx_uartps.c @@ -512,9 +512,6 @@ static void cdns_uart_start_tx(struct uart_port *port) { unsigned int status, numbytes = port->fifosize; - if (uart_circ_empty(&port->state->xmit) || uart_tx_stopped(port)) - return; - /* * Set the TX enable bit and clear the TX disable bit to enable the * transmitter. @@ -524,6 +521,9 @@ static void cdns_uart_start_tx(struct uart_port *port) status |= CDNS_UART_CR_TX_EN; writel(status, port->membase + CDNS_UART_CR_OFFSET); + if (uart_circ_empty(&port->state->xmit) || uart_tx_stopped(port)) + return; + while (numbytes-- && ((readl(port->membase + CDNS_UART_SR_OFFSET) & CDNS_UART_SR_TXFULL)) != CDNS_UART_SR_TXFULL) { /* Break if no more data available in the UART buffer */ -- 2.6.2.3.ga463a5b