Commit a208ffd2 authored Mar 27, 2014 by Grant Likely

of: Enable console on serial ports specified by /chosen/stdout-path



If the devicetree specifies a serial port as a stdout device, then the
kernel can use it as the default console if nothing else was selected on
the command line. For any serial port that uses the uart_add_one_port()
feature, the uart_add_one_port() has all the information needed to
automatically enable the console device, which is what this patch does.

With this change applied, a device tree platform can be booted without
any console= parameters on the command line and the kernel will still be
able to determine its console.

Tested on QEMU Versatile model and i.MX

Signed-off-by: Grant Likely <grant.likely@linaro.org>
Tested-by: Sascha Hauer <s.hauer@pengutronix.de>

parent 3482f2c5

drivers/tty/serial/serial_core.c

+3 −0

Original line number	Diff line number	Diff line
		@@ -26,6 +26,7 @@
		#include <linux/slab.h>
		#include <linux/init.h>
		#include <linux/console.h>
		#include <linux/of.h>
		#include <linux/proc_fs.h>
		#include <linux/seq_file.h>
		#include <linux/device.h>
		@@ -2615,6 +2616,8 @@ int uart_add_one_port(struct uart_driver drv, struct uart_port uport)
		spin_lock_init(&uport->lock);
		lockdep_set_class(&uport->lock, &port_lock_key);
		}
		if (uport->cons && uport->dev)
		of_console_check(uport->dev->of_node, uport->cons->name, uport->line);

		uart_configure_port(drv, state, uport);