[POWERPC] Add of_device_is_available function

IEEE 1275 defined a standard "status" property to indicate the operational
status of a device.  The property has four possible values: okay, disabled,
fail, fail-xxx.  The absence of this property means the operational status
of the device is unknown or okay.

This adds a function called of_device_is_available that checks the state
of the status property of a device.  If the property is absent or set to
either "okay" or "ok", it returns 1.  Otherwise it returns 0.

Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 1 insertions, 0 deletions

diff --git a/include/linux/of.h b/include/linux/of.h
index 6981016..59a61bd 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -62,6 +62,7 @@ extern struct property *of_find_property(const struct device_node *np,
 					 int *lenp);
 extern int of_device_is_compatible(const struct device_node *device,
 				   const char *);
+extern int of_device_is_available(const struct device_node *device);
 extern const void *of_get_property(const struct device_node *node,
 				const char *name,
 				int *lenp);