From mboxrd@z Thu Jan 1 00:00:00 1970 From: Soren Brinkmann Subject: [PATCH LINUX v4 08/13] tty: xuartps: Acquire port lock for shutdown Date: Sat, 5 Dec 2015 20:39:24 -0800 Message-ID: <1449376769-13369-9-git-send-email-soren.brinkmann@xilinx.com> References: <1449376769-13369-1-git-send-email-soren.brinkmann@xilinx.com> Mime-Version: 1.0 Content-Type: text/plain Return-path: In-Reply-To: <1449376769-13369-1-git-send-email-soren.brinkmann@xilinx.com> Sender: linux-kernel-owner@vger.kernel.org To: Greg Kroah-Hartman , Jiri Slaby Cc: Michal Simek , linux-serial@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Peter Hurley , Moritz Fischer , Soren Brinkmann List-Id: linux-serial@vger.kernel.org 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 --- 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