From a19eda0f49e5b19c403c5fe33e1e2f46e7b02082 Mon Sep 17 00:00:00 2001 From: Soren Brinkmann Date: Sat, 26 Dec 2015 02:43:55 -0800 Subject: [PATCH] tty: xuartps: Acquire port lock for shutdown Shutting down the UART port can happen while console operations are in progress. Holding the port lock serializes these operations and avoids the UART HW to be disabled in the middle of console prints. Signed-off-by: Soren Brinkmann Reviewed-by: Peter Hurley Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/xilinx_uartps.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/tty/serial/xilinx_uartps.c b/drivers/tty/serial/xilinx_uartps.c index ab3995d00973..f3ac69387b0a 100644 --- a/drivers/tty/serial/xilinx_uartps.c +++ b/drivers/tty/serial/xilinx_uartps.c @@ -826,6 +826,9 @@ static int cdns_uart_startup(struct uart_port *port) static void cdns_uart_shutdown(struct uart_port *port) { int status; + unsigned long flags; + + spin_lock_irqsave(&port->lock, flags); /* Disable interrupts */ status = readl(port->membase + CDNS_UART_IMR_OFFSET); @@ -835,6 +838,9 @@ static void cdns_uart_shutdown(struct uart_port *port) /* Disable the TX and RX */ writel(CDNS_UART_CR_TX_DIS | CDNS_UART_CR_RX_DIS, port->membase + CDNS_UART_CR_OFFSET); + + spin_unlock_irqrestore(&port->lock, flags); + free_irq(port->irq, port); }