From: Holger Assmann <h.assmann@xxxxxxxxxxxxxx> commit fdf16d78941b4f380753053d229955baddd00712 upstream. stm32_init_port() of the stm32-usart may trigger a warning in platform_get_irq() when the device tree specifies no wakeup interrupt. The wakeup interrupt is usually a board-specific GPIO and the driver functions correctly in its absence. The mainline stm32mp151.dtsi does not specify it, so all mainline device trees trigger an unnecessary kernel warning. Use of platform_get_irq_optional() avoids this. Fixes: 2c58e56096dd ("serial: stm32: fix the get_irq error case") Signed-off-by: Holger Assmann <h.assmann@xxxxxxxxxxxxxx> Cc: stable <stable@xxxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20200813152757.32751-1-h.assmann@xxxxxxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/tty/serial/stm32-usart.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/tty/serial/stm32-usart.c +++ b/drivers/tty/serial/stm32-usart.c @@ -962,7 +962,7 @@ static int stm32_init_port(struct stm32_ return ret; if (stm32port->info->cfg.has_wakeup) { - stm32port->wakeirq = platform_get_irq(pdev, 1); + stm32port->wakeirq = platform_get_irq_optional(pdev, 1); if (stm32port->wakeirq <= 0 && stm32port->wakeirq != -ENXIO) return stm32port->wakeirq ? : -ENODEV; }