From mboxrd@z Thu Jan 1 00:00:00 1970 From: soren.brinkmann@xilinx.com (Soren Brinkmann) Date: Sat, 5 Dec 2015 20:39:20 -0800 Subject: [PATCH LINUX v4 04/13] tty: xuartps: Clear interrupt status register in shutdown In-Reply-To: <1449376769-13369-1-git-send-email-soren.brinkmann@xilinx.com> References: <1449376769-13369-1-git-send-email-soren.brinkmann@xilinx.com> Message-ID: <1449376769-13369-5-git-send-email-soren.brinkmann@xilinx.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org When shutting down the UART, clear the interrupt status register. Bits in the ISR are cleared by writing them as '1'. Signed-off-by: Soren Brinkmann Reviewed-by: Peter Hurley Reviewed-by: Moritz Fischer --- v4: - clarify workings of the ISR in the commit message --- drivers/tty/serial/xilinx_uartps.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/tty/serial/xilinx_uartps.c b/drivers/tty/serial/xilinx_uartps.c index 6a7cd4e057ae..ef114d7a0623 100644 --- a/drivers/tty/serial/xilinx_uartps.c +++ b/drivers/tty/serial/xilinx_uartps.c @@ -828,6 +828,7 @@ static void cdns_uart_shutdown(struct uart_port *port) /* Disable interrupts */ status = readl(port->membase + CDNS_UART_IMR_OFFSET); writel(status, port->membase + CDNS_UART_IDR_OFFSET); + writel(0xffffffff, port->membase + CDNS_UART_ISR_OFFSET); /* Disable the TX and RX */ writel(CDNS_UART_CR_TX_DIS | CDNS_UART_CR_RX_DIS, -- 2.6.3.3.g9bb996a