From 73a810a9ff97055ccbe9d73fdf0acc7e06a72f37 Mon Sep 17 00:00:00 2001 From: Phil Elwell Date: Tue, 23 Feb 2016 17:26:48 +0000 Subject: [PATCH] amba_pl011: Don't use DT aliases for numbering The pl011 driver looks for DT aliases of the form "serial", and if found uses as the device ID. This can cause /dev/ttyAMA0 to become /dev/ttyAMA1, which is confusing if the other serial port is provided by the 8250 driver which doesn't use the same logic. --- drivers/tty/serial/amba-pl011.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c index 899a77187bdea..68b3353c5c035 100644 --- a/drivers/tty/serial/amba-pl011.c +++ b/drivers/tty/serial/amba-pl011.c @@ -2313,7 +2313,12 @@ static int pl011_setup_port(struct device *dev, struct uart_amba_port *uap, if (IS_ERR(base)) return PTR_ERR(base); + /* Don't use DT serial aliases - it causes the device to + be renumbered to ttyAMA1 if it is the second serial port in the + system, even though the other one is ttyS0. The 8250 driver + doesn't use this logic, so always remains ttyS0. index = pl011_probe_dt_alias(index, dev); + */ uap->old_cr = 0; uap->port.dev = dev;