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 <shawn.guo@freescale.com>
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Tested-by: Richard Zhao <richard.zhao@freescale.com>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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 @@
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 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_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);