+static void
+complete_set_busy_timeout(struct fw_card *card, int rcode,
+ void *payload, size_t length, void *done)
+{
+ complete(done);
+}
+
+/*
+ * Write retransmit retry values into the BUSY_TIMEOUT register.
+ * - The single-phase retry protocol is supported by all SBP-2 devices, but the
+ * default retry_limit value is 0 (i.e. never retry transmission). We write a
+ * saner value after logging into the device.
+ * - The dual-phase retry protocol is optional to implement, and if not
+ * supported, writes to the dual-phase portion of the register will be
+ * ignored. We try to write the original 1394-1995 default here.
+ * - In the case of devices that are also SBP-3-compliant, all writes are
+ * ignored, as the register is read-only, but contains single-phase retry of
+ * 15, which is what we're trying to set for all SBP-2 device anyway, so this
+ * write attempt is safe and yields more consistent behavior for all devices.
+ *
+ * See section 8.3.2.3.5 of the 1394-1995 spec, section 6.2 of the SBP-2 spec,
+ * and section 6.4 of the SBP-3 spec for further details.
+ */
+static void sbp2_set_busy_timeout(struct sbp2_logical_unit *lu)
+{
+ struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
+ DECLARE_COMPLETION_ONSTACK(done);
+ struct fw_transaction t;
+ static __be32 busy_timeout;
+
+ busy_timeout = cpu_to_be32(SBP2_CYCLE_LIMIT | SBP2_RETRY_LIMIT);
+
+ fw_send_request(device->card, &t, TCODE_WRITE_QUADLET_REQUEST,
+ lu->tgt->node_id, lu->generation, device->max_speed,
+ CSR_REGISTER_BASE + CSR_BUSY_TIMEOUT, &busy_timeout,
+ sizeof(busy_timeout), complete_set_busy_timeout, &done);
+ wait_for_completion(&done);
+}
+