From db1a9b55004c83ded54c1f869f81a8a59c6dde87 Mon Sep 17 00:00:00 2001 From: Fabio Estevam Date: Tue, 13 Dec 2011 01:23:48 -0200 Subject: [PATCH] tty: serial: imx: Allow UART to be a source for wakeup Allow UART to be a source for wakeup from low power mode. Tested on a MX27PDK by doing: echo enabled > /sys/devices/platform/imx21-uart.0/tty/ttymxc0/power/wakeup echo mem > /sys/power/state and then pressing a key in the console will wakeup the sytem. Suggested-by: Shawn Guo Signed-off-by: Fabio Estevam Tested-by: Richard Zhao Signed-off-by: Shawn Guo Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/imx.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c index 962cafa..ed6e144 100644 --- a/drivers/tty/serial/imx.c +++ b/drivers/tty/serial/imx.c @@ -566,6 +566,9 @@ static irqreturn_t imx_int(int irq, void *dev_id) if (sts & USR1_RTSD) imx_rtsint(irq, dev_id); + if (sts & USR1_AWAKE) + writel(USR1_AWAKE, sport->port.membase + USR1); + return IRQ_HANDLED; } @@ -1269,6 +1272,12 @@ static struct uart_driver imx_reg = { static int serial_imx_suspend(struct platform_device *dev, pm_message_t state) { struct imx_port *sport = platform_get_drvdata(dev); + unsigned int val; + + /* enable wakeup from i.MX UART */ + val = readl(sport->port.membase + UCR3); + val |= UCR3_AWAKEN; + writel(val, sport->port.membase + UCR3); if (sport) uart_suspend_port(&imx_reg, &sport->port); @@ -1279,6 +1288,12 @@ static int serial_imx_suspend(struct platform_device *dev, pm_message_t state) static int serial_imx_resume(struct platform_device *dev) { struct imx_port *sport = platform_get_drvdata(dev); + unsigned int val; + + /* disable wakeup from i.MX UART */ + val = readl(sport->port.membase + UCR3); + val &= ~UCR3_AWAKEN; + writel(val, sport->port.membase + UCR3); if (sport) uart_resume_port(&imx_reg, &sport->port); -- 2.7.4