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>
diff --git a/drivers/firewire/core-transaction.c b/drivers/firewire/core-transaction.c
index a61eb3f..dd8ef65 100644
--- a/drivers/firewire/core-transaction.c
+++ b/drivers/firewire/core-transaction.c
@@ -1140,6 +1140,15 @@
rcode = RCODE_TYPE_ERROR;
break;
+ case CSR_MAINT_UTILITY:
+ if (tcode == TCODE_READ_QUADLET_REQUEST)
+ *data = card->maint_utility_register;
+ else if (tcode == TCODE_WRITE_QUADLET_REQUEST)
+ card->maint_utility_register = *data;
+ else
+ rcode = RCODE_TYPE_ERROR;
+ break;
+
case CSR_BROADCAST_CHANNEL:
if (tcode == TCODE_READ_QUADLET_REQUEST)
*data = cpu_to_be32(card->broadcast_channel);
diff --git a/include/linux/firewire.h b/include/linux/firewire.h
index a50377d..f1160e8 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 @@
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 {