tty/serial: of_serial: add DT alias ID handling

Add support for alias parsing from the DT. This allows for consistent
tty numbering.

Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: linux-serial@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 4 insertions, 0 deletions

diff --git a/drivers/tty/serial/of_serial.c b/drivers/tty/serial/of_serial.c
index 64f1bab7e9d7..3194b42c97c0 100644
--- a/drivers/tty/serial/of_serial.c
+++ b/drivers/tty/serial/of_serial.c
@@ -128,6 +128,10 @@ static int of_platform_serial_setup(struct platform_device *ofdev,
         if (of_find_property(np, "no-loopback-test", NULL))
                 port->flags |= UPF_SKIP_TEST;
 
+        ret = of_alias_get_id(np, "serial");
+        if (ret >= 0)
+                port->line = ret;
+
         port->dev = &ofdev->dev;
 
         switch (type) {