From 16804d68bfaa7f5f5a73ab4a016ffeba33e87770 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Uwe=20Kleine-K=C3=B6nig?= Date: Thu, 24 Mar 2016 14:24:22 +0100 Subject: [PATCH] serial: imx: make sure unhandled irqs are disabled MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Make sure that events that are not handled in the irq function don't trigger an interrupt. When the serial port is operated in DTE mode, the events for DCD and RI events are enabled after a system reset by default. Signed-off-by: Uwe Kleine-König Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/imx.c | 23 ++++++++++++++++++++++- 1 file changed, 22 insertions(+), 1 deletion(-) diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c index 46769168fab7..aa07301df262 100644 --- a/drivers/tty/serial/imx.c +++ b/drivers/tty/serial/imx.c @@ -1224,11 +1224,32 @@ static int imx_startup(struct uart_port *port) temp |= (UCR2_RXEN | UCR2_TXEN); if (!sport->have_rtscts) temp |= UCR2_IRTS; + /* + * make sure the edge sensitive RTS-irq is disabled, + * we're using RTSD instead. + */ + if (!is_imx1_uart(sport)) + temp &= ~UCR2_RTSEN; writel(temp, sport->port.membase + UCR2); if (!is_imx1_uart(sport)) { temp = readl(sport->port.membase + UCR3); - temp |= IMX21_UCR3_RXDMUXSEL | UCR3_ADNIMP; + + /* + * The effect of RI and DCD differs depending on the UFCR_DCEDTE + * bit. In DCE mode they control the outputs, in DTE mode they + * enable the respective irqs. At least the DCD irq cannot be + * cleared on i.MX25 at least, so it's not usable and must be + * disabled. I don't have test hardware to check if RI has the + * same problem but I consider this likely so it's disabled for + * now, too. + */ + temp |= IMX21_UCR3_RXDMUXSEL | UCR3_ADNIMP | + UCR3_RI | UCR3_DCD; + + if (sport->dte_mode) + temp &= ~(UCR3_RI | UCR3_DCD); + writel(temp, sport->port.membase + UCR3); } -- 2.20.1