Prevent writing to the fifo if the controller is disabled.
Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xxxxxxxxxx>
---
v2:
Add atimeout
drivers/tty/serial/xilinx_uartps.c | 15 +++++++++++++++
1 file changed, 15 insertions(+)
diff --git a/drivers/tty/serial/xilinx_uartps.c b/drivers/tty/serial/xilinx_uartps.c
index ae99e1164f0c..e119da69e190 100644
--- a/drivers/tty/serial/xilinx_uartps.c
+++ b/drivers/tty/serial/xilinx_uartps.c
@@ -1132,6 +1132,21 @@ static struct uart_driver cdns_uart_uart_driver;
*/
static void cdns_uart_console_putchar(struct uart_port *port, unsigned char ch)
{
+ unsigned int ctrl_reg;
+ unsigned long timeout;
+
+ timeout = jiffies + msecs_to_jiffies(1000);
+ while (1) {
+ ctrl_reg = readl(port->membase + CDNS_UART_CR);
+ if (!(ctrl_reg & CDNS_UART_CR_TX_DIS))
+ break;
+ if (time_after(jiffies, timeout)) {
+ dev_warn(port->dev,
+ "timeout waiting for Enable\n");
+ return;
+ }
+ cpu_relax();
+ }
while (readl(port->membase + CDNS_UART_SR) & CDNS_UART_SR_TXFULL)
cpu_relax();
writel(ch, port->membase + CDNS_UART_FIFO);
--
2.25.1
