6.18-stable review patch. If anyone has any objections, please let me know.
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From: Sherry Sun sherry.sun@nxp.com
[ Upstream commit d55f3d2375ceeb08330d30f1e08196993c0b6583 ]
Currently, the i.MX UART driver enables wake-related registers for all UART devices by default. However, this is unnecessary for devices that are not configured as wakeup sources. To address this, add a device_may_wakeup() check before configuring the UART wake-related registers.
Fixes: db1a9b55004c ("tty: serial: imx: Allow UART to be a source for wakeup") Signed-off-by: Sherry Sun sherry.sun@nxp.com Reviewed-by: Frank Li Frank.Li@nxp.com Link: https://patch.msgid.link/20251002045259.2725461-2-sherry.sun@nxp.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/tty/serial/imx.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+)
diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c index 500dfc009d03e..90e2ea1e8afe5 100644 --- a/drivers/tty/serial/imx.c +++ b/drivers/tty/serial/imx.c @@ -2697,8 +2697,22 @@ static void imx_uart_save_context(struct imx_port *sport) /* called with irq off */ static void imx_uart_enable_wakeup(struct imx_port *sport, bool on) { + struct tty_port *port = &sport->port.state->port; + struct device *tty_dev; + bool may_wake = false; u32 ucr3;
+ scoped_guard(tty_port_tty, port) { + struct tty_struct *tty = scoped_tty(); + + tty_dev = tty->dev; + may_wake = tty_dev && device_may_wakeup(tty_dev); + } + + /* only configure the wake register when device set as wakeup source */ + if (!may_wake) + return; + uart_port_lock_irq(&sport->port);
ucr3 = imx_uart_readl(sport, UCR3);