firewire: core: add CSR MAINT_UTILITY support

Implement the MAIN_UTILITY register, which is utterly optional
but useful as a safe target for diagnostic read/write/broadcast
transactions.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>

1 files changed, 3 insertions, 0 deletions

diff --git a/include/linux/firewire.h b/include/linux/firewire.h
index a50377d91254..f1160e831dad 100644
--- a/include/linux/firewire.h
+++ b/include/linux/firewire.h
@@ -38,6 +38,7 @@
 #define CSR_CHANNELS_AVAILABLE          0x224
 #define CSR_CHANNELS_AVAILABLE_HI       0x224
 #define CSR_CHANNELS_AVAILABLE_LO       0x228
+#define CSR_MAINT_UTILITY               0x230
 #define CSR_BROADCAST_CHANNEL           0x234
 #define CSR_CONFIG_ROM                  0x400
 #define CSR_CONFIG_ROM_END              0x800
@@ -122,6 +123,8 @@ struct fw_card {
         bool broadcast_channel_allocated;
         u32 broadcast_channel;
         __be32 topology_map[(CSR_TOPOLOGY_MAP_END - CSR_TOPOLOGY_MAP) / 4];
+
+        __be32 maint_utility_register;
 };
 
 struct fw_attribute_group {