From mboxrd@z Thu Jan 1 00:00:00 1970 From: Soren Brinkmann Subject: [PATCH LINUX 1/6] tty: xuartps: Move request_irq to after setting up the HW Date: Mon, 11 Jan 2016 17:41:36 -0800 Message-ID: <1452562901-17848-2-git-send-email-soren.brinkmann@xilinx.com> References: <1452562901-17848-1-git-send-email-soren.brinkmann@xilinx.com> Mime-Version: 1.0 Content-Type: text/plain Return-path: In-Reply-To: <1452562901-17848-1-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 , Soren Brinkmann List-Id: linux-serial@vger.kernel.org Request_irq() should be _after_ h/w programming, otherwise an interrupt could be triggered and in-progress before the h/w has been setup. Reported-by: Peter Hurley Signed-off-by: Soren Brinkmann --- drivers/tty/serial/xilinx_uartps.c | 21 ++++++++++++--------- 1 file changed, 12 insertions(+), 9 deletions(-) diff --git a/drivers/tty/serial/xilinx_uartps.c b/drivers/tty/serial/xilinx_uartps.c index db9e23eaf300..5da1c51e9e40 100644 --- a/drivers/tty/serial/xilinx_uartps.c +++ b/drivers/tty/serial/xilinx_uartps.c @@ -762,13 +762,9 @@ static void cdns_uart_set_termios(struct uart_port *port, */ static int cdns_uart_startup(struct uart_port *port) { + int ret; unsigned long flags; - unsigned int retval = 0, status = 0; - - retval = request_irq(port->irq, cdns_uart_isr, 0, CDNS_UART_NAME, - (void *)port); - if (retval) - return retval; + unsigned int status = 0; spin_lock_irqsave(&port->lock, flags); @@ -814,15 +810,22 @@ static int cdns_uart_startup(struct uart_port *port) writel(readl(port->membase + CDNS_UART_ISR_OFFSET), port->membase + CDNS_UART_ISR_OFFSET); + spin_unlock_irqrestore(&port->lock, flags); + + ret = request_irq(port->irq, cdns_uart_isr, 0, CDNS_UART_NAME, port); + if (ret) { + dev_err(port->dev, "request_irq '%d' failed with %d\n", + port->irq, ret); + return ret; + } + /* Set the Interrupt Registers with desired interrupts */ writel(CDNS_UART_IXR_TXEMPTY | CDNS_UART_IXR_PARITY | CDNS_UART_IXR_FRAMING | CDNS_UART_IXR_OVERRUN | CDNS_UART_IXR_RXTRIG | CDNS_UART_IXR_TOUT, port->membase + CDNS_UART_IER_OFFSET); - spin_unlock_irqrestore(&port->lock, flags); - - return retval; + return 0; } /** -- 2.7.0.3.g497ea1e