[PATCH LINUX v4 08/13] tty: xuartps: Acquire port lock for shutdown
From: Soren Brinkmann <hidden>
Date: 2015-12-06 04:40:05
Also in:
linux-serial, lkml
Subsystem:
the rest, tty layer and serial drivers · Maintainers:
Linus Torvalds, Greg Kroah-Hartman, Jiri Slaby
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 <redacted> Reviewed-by: Peter Hurley <redacted> --- 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 62224a58056b..80248cb46bf6 100644
--- a/drivers/tty/serial/xilinx_uartps.c
+++ b/drivers/tty/serial/xilinx_uartps.c@@ -821,6 +821,9 @@ 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);
@@ -830,6 +833,9 @@ 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); }
--
2.6.3.3.g9bb996a