firewire: core: add is_local sysfs device attribute

Making this information available in sysfs allows to differentiate
between controllers in the local and remote Linux PCs, and thus is
useful for servers that are started with udev rules.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>

drivers/firewire/core-device.c

@@ -398,6 +398,14 @@ static ssize_t guid_show(struct device *dev,
 	return ret;
 }
 
+static ssize_t is_local_show(struct device *dev,
+			     struct device_attribute *attr, char *buf)
+{
+	struct fw_device *device = fw_device(dev);
+
+	return sprintf(buf, "%u\n", device->is_local);
+}
+
 static int units_sprintf(char *buf, const u32 *directory)
 {
 	struct fw_csr_iterator ci;
@@ -447,6 +455,7 @@ static ssize_t units_show(struct device *dev,
 static struct device_attribute fw_device_attributes[] = {
 	__ATTR_RO(config_rom),
 	__ATTR_RO(guid),
+	__ATTR_RO(is_local),
 	__ATTR_RO(units),
 	__ATTR_NULL,
 };

include/linux/firewire.h

@@ -138,7 +138,7 @@ struct fw_card {
 struct fw_attribute_group {
 	struct attribute_group *groups[2];
 	struct attribute_group group;
-	struct attribute *attrs[12];
+	struct attribute *attrs[13];
 };
 
 enum fw_device_state {