From 22130dae0533c474e4e0db930a88caa9b397d083 Mon Sep 17 00:00:00 2001 From: Jisheng Zhang Date: Sun, 6 Aug 2023 17:20:56 +0800 Subject: [PATCH] serial: 8250_dw: fall back to poll if there's no interrupt When there's no irq(this can be due to various reasons, for example, no irq from HW support, or we just want to use poll solution, and so on), falling back to poll is still better than no support at all. Signed-off-by: Jisheng Zhang Link: https://lore.kernel.org/r/20230806092056.2467-3-jszhang@kernel.org Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/8250/8250_dw.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/tty/serial/8250/8250_dw.c b/drivers/tty/serial/8250/8250_dw.c index 7db51781289e..f4cafca1a7da 100644 --- a/drivers/tty/serial/8250/8250_dw.c +++ b/drivers/tty/serial/8250/8250_dw.c @@ -523,7 +523,10 @@ static int dw8250_probe(struct platform_device *pdev) if (!regs) return dev_err_probe(dev, -EINVAL, "no registers defined\n"); - irq = platform_get_irq(pdev, 0); + irq = platform_get_irq_optional(pdev, 0); + /* no interrupt -> fall back to polling */ + if (irq == -ENXIO) + irq = 0; if (irq < 0) return irq;