firewire: reread config ROM when device reset the bus

When a device changes its configuration ROM, it announces this with a
bus reset.  firewire-core has to check which node initiated a bus reset
and whether any unit directories went away or were added on this node.

Tested with an IOI FWB-IDE01AB which has its link-on bit set if bus
power is available but does not respond to ROM read requests if self
power is off.  This implements
  - recognition of the units if self power is switched on after fw-core
    gave up the initial attempt to read the config ROM,
  - shutdown of the units when self power is switched off.

Also tested with a second PC running Linux/ieee1394.  When the eth1394
driver is inserted and removed on that node, fw-core now notices the
addition and removal of the IPv4 unit on the ieee1394 node.

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

1 files changed, 4 insertions, 4 deletions

diff --git a/drivers/firewire/fw-sbp2.c b/drivers/firewire/fw-sbp2.c
index e99a33fcc923..2a999373863e 100644
--- a/drivers/firewire/fw-sbp2.c
+++ b/drivers/firewire/fw-sbp2.c
@@ -153,6 +153,7 @@ struct sbp2_target {
         struct list_head lu_list;
 
         u64 management_agent_address;
+        u64 guid;
         int directory_id;
         int node_id;
         int address_high;
@@ -1114,6 +1115,7 @@ static int sbp2_probe(struct device *dev)
         kref_init(&tgt->kref);
         INIT_LIST_HEAD(&tgt->lu_list);
         tgt->bus_id = unit->device.bus_id;
+        tgt->guid = (u64)device->config_rom[3] << 32 | device->config_rom[4];
 
         if (fw_device_enable_phys_dma(device) < 0)
                 goto fail_shost_put;
@@ -1571,16 +1573,14 @@ sbp2_sysfs_ieee1394_id_show(struct device *dev, struct device_attribute *attr,
 {
         struct scsi_device *sdev = to_scsi_device(dev);
         struct sbp2_logical_unit *lu;
-        struct fw_device *device;
 
         if (!sdev)
                 return 0;
 
         lu = sdev->hostdata;
-        device = fw_device(lu->tgt->unit->device.parent);
 
-        return sprintf(buf, "%08x%08x:%06x:%04x\n",
-                        device->config_rom[3], device->config_rom[4],
+        return sprintf(buf, "%016llx:%06x:%04x\n",
+                        (unsigned long long)lu->tgt->guid,
                         lu->tgt->directory_id, lu->lun);
 }