firewire: cdev: fix fw_cdev_event_bus_reset.bm_node_id
Fix an obscure ABI feature that is a bit of a hassle to implement.
However, somebody put it into the ABI, so let's fill in a sensible
value there.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
diff --git a/include/linux/firewire-cdev.h b/include/linux/firewire-cdev.h
index 8b9b273..d31022b 100644
--- a/include/linux/firewire-cdev.h
+++ b/include/linux/firewire-cdev.h
@@ -66,6 +66,10 @@
* This event is sent when the bus the device belongs to goes through a bus
* reset. It provides information about the new bus configuration, such as
* new node ID for this device, new root ID, and others.
+ *
+ * If @bm_node_id is 0xffff right after bus reset it can be reread by an
+ * %FW_CDEV_IOC_GET_INFO ioctl after bus manager selection was finished.
+ * Kernels with ABI version < 4 do not set @bm_node_id.
*/
struct fw_cdev_event_bus_reset {
__u64 closure;
@@ -348,6 +352,7 @@
* 3 (2.6.34) - made &fw_cdev_get_cycle_timer reliable
* - added %FW_CDEV_IOC_GET_CYCLE_TIMER2
* 4 (2.6.36) - added %FW_CDEV_EVENT_REQUEST2
+ * - implemented &fw_cdev_event_bus_reset.bm_node_id
*/
#define FW_CDEV_VERSION 3 /* Meaningless; don't use this macro. */