Get serial id from dts. "#ifdef CONFIG_LANTIQ" preprocessor is used because LTQ_EARLY_ASC macro is defined in lantiq_soc.h. lantiq_soc.h is in arch path for legacy product support. arch/mips/include/asm/mach-lantiq/xway/lantiq_soc.h If "#ifdef preprocessor" is changed to "if (IS_ENABLED(CONFIG_LANTIQ))", when CONFIG_LANTIQ is not enabled, code using LTQ_EARLY_ASC is compiled. Compilation will fail for no LTQ_EARLY_ASC defined. Signed-off-by: Songjun Wu <songjun.wu@xxxxxxxxxxxxxxx> --- Changes in v2: None drivers/tty/serial/lantiq.c | 19 +++++++++++++++---- 1 file changed, 15 insertions(+), 4 deletions(-) diff --git a/drivers/tty/serial/lantiq.c b/drivers/tty/serial/lantiq.c index 044128277248..836ca51460f2 100644 --- a/drivers/tty/serial/lantiq.c +++ b/drivers/tty/serial/lantiq.c @@ -6,6 +6,7 @@ * Copyright (C) 2007 Felix Fietkau <nbd@xxxxxxxxxxx> * Copyright (C) 2007 John Crispin <john@xxxxxxxxxxx> * Copyright (C) 2010 Thomas Langer, <thomas.langer@xxxxxxxxxx> + * Copyright (C) 2018 Intel Corporation. */ #include <linux/slab.h> @@ -688,7 +689,7 @@ lqasc_probe(struct platform_device *pdev) struct ltq_uart_port *ltq_port; struct uart_port *port; struct resource *mmres, irqres[3]; - int line = 0; + int line; int ret; mmres = platform_get_resource(pdev, IORESOURCE_MEM, 0); @@ -699,9 +700,19 @@ lqasc_probe(struct platform_device *pdev) return -ENODEV; } - /* check if this is the console port */ - if (mmres->start != CPHYSADDR(LTQ_EARLY_ASC)) - line = 1; + /* get serial id */ + line = of_alias_get_id(node, "serial"); + if (line < 0) { +#ifdef CONFIG_LANTIQ + if (mmres->start == CPHYSADDR(LTQ_EARLY_ASC)) + line = 0; + else + line = 1; +#else + dev_err(&pdev->dev, "failed to get alias id, errno %d\n", line); + return line; +#endif + } if (lqasc_port[line]) { dev_err(&pdev->dev, "port %d already allocated\n", line); -- 2.11.0