[PATCH] tty: serial: fsl_lpuart: Add missing wakeup event reporting

From: Sherry Sun

Date: Tue Sep 23 2025 - 10:12:15 EST


Current lpuart wakeup event would not report itself through sysfs as
being the source of wakeup, so add pm_wakeup_event() to support this.

Signed-off-by: Sherry Sun <sherry.sun@xxxxxxx>
---
drivers/tty/serial/fsl_lpuart.c | 8 ++++++++
1 file changed, 8 insertions(+)

diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c
index c9519e649e82..9625997758e1 100644
--- a/drivers/tty/serial/fsl_lpuart.c
+++ b/drivers/tty/serial/fsl_lpuart.c
@@ -3087,7 +3087,9 @@ static int lpuart_suspend_noirq(struct device *dev)
static int lpuart_resume_noirq(struct device *dev)
{
struct lpuart_port *sport = dev_get_drvdata(dev);
+ struct tty_port *port = &sport->port.state->port;
u32 stat;
+ bool wake_active;

pinctrl_pm_select_default_state(dev);

@@ -3098,6 +3100,12 @@ static int lpuart_resume_noirq(struct device *dev)
if (lpuart_is_32(sport)) {
stat = lpuart32_read(&sport->port, UARTSTAT);
lpuart32_write(&sport->port, stat, UARTSTAT);
+
+ /* check whether lpuart wakeup was triggered */
+ wake_active = stat & UARTSTAT_RDRF || stat & UARTSTAT_RXEDGIF;
+
+ if (wake_active && irqd_is_wakeup_set(irq_get_irq_data(sport->port.irq)))
+ pm_wakeup_event(tty_port_tty_get(port)->dev, 0);
}
}

--
2.34.1