[PATCH 2/2][POWERPC] Ignore disabled serial ports

[Josh Boyer <jwboyer@linux.vnet.ibm.com>]

Some SoC chips have multiple serial ports on board.  The usability of these
ports can rely on various factors, ranging from pin sharing to unpopulated
connectors.  This uses the new of_device_is_disabled function to check for
and ignore disabled UARTs.

Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>

---
 arch/powerpc/kernel/legacy_serial.c |    4 ++++
 drivers/serial/of_serial.c          |    5 +++++
 2 files changed, 9 insertions(+)

--- linux-2.6.orig/drivers/serial/of_serial.c
+++ linux-2.6/drivers/serial/of_serial.c
@@ -72,6 +72,11 @@ static int __devinit of_platform_serial_
 	int port_type;
 	int ret;
 
+	if (of_device_is_disabled(ofdev->node)) {
+		dev_info(&ofdev->dev, "Disabled serial port.  Ignored\n");
+		return -ENODEV;
+	}
+
 	if (of_find_property(ofdev->node, "used-by-rtas", NULL))
 		return -EBUSY;
 
--- linux-2.6.orig/arch/powerpc/kernel/legacy_serial.c
+++ linux-2.6/arch/powerpc/kernel/legacy_serial.c
@@ -54,6 +54,10 @@ static int __init add_legacy_port(struct
 	u32 clock = BASE_BAUD * 16;
 	int index;
 
+	/* Check the status property if present.  Ignore disabled devices */
+	if (of_device_is_disabled(np))
+		return -1;
+
 	/* get clock freq. if present */
 	clk = of_get_property(np, "clock-frequency", NULL);
 	if (clk && *clk)