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authorKristian Høgsberg <krh@redhat.com>2006-12-20 03:58:27 +0300
committerStefan Richter <stefanr@s5r6.in-berlin.de>2007-03-10 00:02:33 +0300
commit3038e353cfaf548eb94f02b172b9dbe412abd24c (patch)
tree70e50c20e117e2dacb7cd810d00fe595e60d26ce /drivers/firewire/fw-transaction.c
parent08e15e81a40e3241ce93b4a43886f3abda184aa6 (diff)
downloadlinux-3038e353cfaf548eb94f02b172b9dbe412abd24c.tar.xz
firewire: Add core firewire stack.
Signed-off-by: Kristian Høgsberg <krh@redhat.com> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Diffstat (limited to 'drivers/firewire/fw-transaction.c')
-rw-r--r--drivers/firewire/fw-transaction.c730
1 files changed, 730 insertions, 0 deletions
diff --git a/drivers/firewire/fw-transaction.c b/drivers/firewire/fw-transaction.c
new file mode 100644
index 000000000000..c3acf7431279
--- /dev/null
+++ b/drivers/firewire/fw-transaction.c
@@ -0,0 +1,730 @@
+/* -*- c-basic-offset: 8 -*-
+ *
+ * fw-transaction.c - core IEEE1394 transaction logic
+ *
+ * Copyright (C) 2004-2006 Kristian Hoegsberg <krh@bitplanet.net>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/pci.h>
+#include <linux/delay.h>
+#include <linux/poll.h>
+#include <linux/list.h>
+#include <linux/kthread.h>
+#include <asm/uaccess.h>
+#include <asm/semaphore.h>
+
+#include "fw-transaction.h"
+#include "fw-topology.h"
+
+#define header_pri(pri) ((pri) << 0)
+#define header_tcode(tcode) ((tcode) << 4)
+#define header_retry(retry) ((retry) << 8)
+#define header_tlabel(tlabel) ((tlabel) << 10)
+#define header_destination(destination) ((destination) << 16)
+#define header_source(source) ((source) << 16)
+#define header_rcode(rcode) ((rcode) << 12)
+#define header_offset_high(offset_high) ((offset_high) << 0)
+#define header_data_length(length) ((length) << 16)
+#define header_extended_tcode(tcode) ((tcode) << 0)
+
+#define header_get_tcode(q) (((q) >> 4) & 0x0f)
+#define header_get_tlabel(q) (((q) >> 10) & 0x3f)
+#define header_get_rcode(q) (((q) >> 4) & 0x0f)
+#define header_get_destination(q) (((q) >> 16) & 0xffff)
+#define header_get_source(q) (((q) >> 16) & 0xffff)
+#define header_get_offset_high(q) (((q) >> 0) & 0xffff)
+#define header_get_data_length(q) (((q) >> 16) & 0xffff)
+#define header_get_extended_tcode(q) (((q) >> 0) & 0xffff)
+
+#define phy_config_gap_count(gap_count) (((gap_count) << 16) | (1 << 22))
+#define phy_config_root_id(node_id) (((node_id) << 24) | (1 << 23))
+#define phy_identifier(id) ((id) << 30)
+
+static void
+close_transaction(struct fw_transaction *t, struct fw_card *card, int rcode,
+ u32 * payload, size_t length)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&card->lock, flags);
+ card->tlabel_mask &= ~(1 << t->tlabel);
+ list_del(&t->link);
+ spin_unlock_irqrestore(&card->lock, flags);
+
+ t->callback(card, rcode, payload, length, t->callback_data);
+}
+
+static void
+transmit_complete_callback(struct fw_packet *packet,
+ struct fw_card *card, int status)
+{
+ struct fw_transaction *t =
+ container_of(packet, struct fw_transaction, packet);
+
+ switch (status) {
+ case ACK_COMPLETE:
+ close_transaction(t, card, RCODE_COMPLETE, NULL, 0);
+ break;
+ case ACK_PENDING:
+ t->timestamp = packet->timestamp;
+ break;
+ case ACK_BUSY_X:
+ case ACK_BUSY_A:
+ case ACK_BUSY_B:
+ close_transaction(t, card, RCODE_BUSY, NULL, 0);
+ break;
+ case ACK_DATA_ERROR:
+ case ACK_TYPE_ERROR:
+ close_transaction(t, card, RCODE_SEND_ERROR, NULL, 0);
+ break;
+ default:
+ /* FIXME: In this case, status is a negative errno,
+ * corresponding to an OHCI specific transmit error
+ * code. We should map that to an RCODE instead of
+ * just the generic RCODE_SEND_ERROR. */
+ close_transaction(t, card, RCODE_SEND_ERROR, NULL, 0);
+ break;
+ }
+}
+
+void
+fw_fill_packet(struct fw_packet *packet, int tcode, int tlabel,
+ int node_id, int generation, int speed,
+ unsigned long long offset, void *payload, size_t length)
+{
+ int ext_tcode;
+
+ if (tcode > 0x10) {
+ ext_tcode = tcode - 0x10;
+ tcode = TCODE_LOCK_REQUEST;
+ } else
+ ext_tcode = 0;
+
+ packet->header[0] =
+ header_retry(RETRY_X) |
+ header_tlabel(tlabel) |
+ header_tcode(tcode) |
+ header_destination(node_id | LOCAL_BUS);
+ packet->header[1] =
+ header_offset_high(offset >> 32) | header_source(0);
+ packet->header[2] =
+ offset;
+
+ switch (tcode) {
+ case TCODE_WRITE_QUADLET_REQUEST:
+ packet->header[3] = *(u32 *)payload;
+ packet->header_length = 16;
+ packet->payload_length = 0;
+ break;
+
+ case TCODE_LOCK_REQUEST:
+ case TCODE_WRITE_BLOCK_REQUEST:
+ packet->header[3] =
+ header_data_length(length) |
+ header_extended_tcode(ext_tcode);
+ packet->header_length = 16;
+ packet->payload = payload;
+ packet->payload_length = length;
+ break;
+
+ case TCODE_READ_QUADLET_REQUEST:
+ packet->header_length = 12;
+ packet->payload_length = 0;
+ break;
+
+ case TCODE_READ_BLOCK_REQUEST:
+ packet->header[3] =
+ header_data_length(length) |
+ header_extended_tcode(ext_tcode);
+ packet->header_length = 16;
+ packet->payload_length = 0;
+ break;
+ }
+
+ packet->speed = speed;
+ packet->generation = generation;
+}
+
+/**
+ * This function provides low-level access to the IEEE1394 transaction
+ * logic. Most C programs would use either fw_read(), fw_write() or
+ * fw_lock() instead - those function are convenience wrappers for
+ * this function. The fw_send_request() function is primarily
+ * provided as a flexible, one-stop entry point for languages bindings
+ * and protocol bindings.
+ *
+ * FIXME: Document this function further, in particular the possible
+ * values for rcode in the callback. In short, we map ACK_COMPLETE to
+ * RCODE_COMPLETE, internal errors set errno and set rcode to
+ * RCODE_SEND_ERROR (which is out of range for standard ieee1394
+ * rcodes). All other rcodes are forwarded unchanged. For all
+ * errors, payload is NULL, length is 0.
+ *
+ * Can not expect the callback to be called before the function
+ * returns, though this does happen in some cases (ACK_COMPLETE and
+ * errors).
+ *
+ * The payload is only used for write requests and must not be freed
+ * until the callback has been called.
+ *
+ * @param card the card from which to send the request
+ * @param tcode the tcode for this transaction. Do not use
+ * TCODE_LOCK_REQUEST directly, insted use TCODE_LOCK_MASK_SWAP
+ * etc. to specify tcode and ext_tcode.
+ * @param node_id the node_id of the destination node
+ * @param generation the generation for which node_id is valid
+ * @param speed the speed to use for sending the request
+ * @param offset the 48 bit offset on the destination node
+ * @param payload the data payload for the request subaction
+ * @param length the length in bytes of the data to read
+ * @param callback function to be called when the transaction is completed
+ * @param callback_data pointer to arbitrary data, which will be
+ * passed to the callback
+ */
+void
+fw_send_request(struct fw_card *card, struct fw_transaction *t,
+ int tcode, int node_id, int generation, int speed,
+ unsigned long long offset,
+ void *payload, size_t length,
+ fw_transaction_callback_t callback, void *callback_data)
+{
+ unsigned long flags;
+ int tlabel;
+
+ /* Bump the flush timer up 100ms first of all so we
+ * don't race with a flush timer callback. */
+
+ mod_timer(&card->flush_timer, jiffies + DIV_ROUND_UP(HZ, 10));
+
+ /* Allocate tlabel from the bitmap and put the transaction on
+ * the list while holding the card spinlock. */
+
+ spin_lock_irqsave(&card->lock, flags);
+
+ tlabel = card->current_tlabel;
+ if (card->tlabel_mask & (1 << tlabel)) {
+ spin_unlock_irqrestore(&card->lock, flags);
+ callback(card, RCODE_SEND_ERROR, NULL, 0, callback_data);
+ return;
+ }
+
+ card->current_tlabel = (card->current_tlabel + 1) & 0x1f;
+ card->tlabel_mask |= (1 << tlabel);
+
+ list_add_tail(&t->link, &card->transaction_list);
+
+ spin_unlock_irqrestore(&card->lock, flags);
+
+ /* Initialize rest of transaction, fill out packet and send it. */
+ t->node_id = node_id;
+ t->tlabel = tlabel;
+ t->callback = callback;
+ t->callback_data = callback_data;
+
+ fw_fill_packet(&t->packet, tcode, t->tlabel,
+ node_id, generation, speed, offset, payload, length);
+ t->packet.callback = transmit_complete_callback;
+
+ card->driver->send_request(card, &t->packet);
+}
+EXPORT_SYMBOL(fw_send_request);
+
+static void
+transmit_phy_packet_callback(struct fw_packet *packet,
+ struct fw_card *card, int status)
+{
+ kfree(packet);
+}
+
+static void send_phy_packet(struct fw_card *card, u32 data, int generation)
+{
+ struct fw_packet *packet;
+
+ packet = kzalloc(sizeof *packet, GFP_ATOMIC);
+ if (packet == NULL)
+ return;
+
+ packet->header[0] = data;
+ packet->header[1] = ~data;
+ packet->header_length = 8;
+ packet->payload_length = 0;
+ packet->speed = SCODE_100;
+ packet->generation = generation;
+ packet->callback = transmit_phy_packet_callback;
+
+ card->driver->send_request(card, packet);
+}
+
+void fw_send_force_root(struct fw_card *card, int node_id, int generation)
+{
+ u32 q;
+
+ q = phy_identifier(PHY_PACKET_CONFIG) | phy_config_root_id(node_id);
+ send_phy_packet(card, q, generation);
+}
+
+void fw_flush_transactions(struct fw_card *card)
+{
+ struct fw_transaction *t, *next;
+ struct list_head list;
+ unsigned long flags;
+
+ INIT_LIST_HEAD(&list);
+ spin_lock_irqsave(&card->lock, flags);
+ list_splice_init(&card->transaction_list, &list);
+ card->tlabel_mask = 0;
+ spin_unlock_irqrestore(&card->lock, flags);
+
+ list_for_each_entry_safe(t, next, &list, link)
+ t->callback(card, RCODE_CANCELLED, NULL, 0, t->callback_data);
+}
+
+static struct fw_address_handler *
+lookup_overlapping_address_handler(struct list_head *list,
+ unsigned long long offset, size_t length)
+{
+ struct fw_address_handler *handler;
+
+ list_for_each_entry(handler, list, link) {
+ if (handler->offset < offset + length &&
+ offset < handler->offset + handler->length)
+ return handler;
+ }
+
+ return NULL;
+}
+
+static struct fw_address_handler *
+lookup_enclosing_address_handler(struct list_head *list,
+ unsigned long long offset, size_t length)
+{
+ struct fw_address_handler *handler;
+
+ list_for_each_entry(handler, list, link) {
+ if (handler->offset <= offset &&
+ offset + length <= handler->offset + handler->length)
+ return handler;
+ }
+
+ return NULL;
+}
+
+static DEFINE_SPINLOCK(address_handler_lock);
+static LIST_HEAD(address_handler_list);
+
+struct fw_address_region fw_low_memory_region =
+ { 0x000000000000ull, 0x000100000000ull };
+struct fw_address_region fw_high_memory_region =
+ { 0x000100000000ull, 0xffffe0000000ull };
+struct fw_address_region fw_private_region =
+ { 0xffffe0000000ull, 0xfffff0000000ull };
+struct fw_address_region fw_csr_region =
+ { 0xfffff0000000ULL, 0xfffff0000800ull };
+struct fw_address_region fw_unit_space_region =
+ { 0xfffff0000900ull, 0x1000000000000ull };
+
+EXPORT_SYMBOL(fw_low_memory_region);
+EXPORT_SYMBOL(fw_high_memory_region);
+EXPORT_SYMBOL(fw_private_region);
+EXPORT_SYMBOL(fw_csr_region);
+EXPORT_SYMBOL(fw_unit_space_region);
+
+/**
+ * Allocate a range of addresses in the node space of the OHCI
+ * controller. When a request is received that falls within the
+ * specified address range, the specified callback is invoked. The
+ * parameters passed to the callback give the details of the
+ * particular request
+ */
+
+int
+fw_core_add_address_handler(struct fw_address_handler *handler,
+ struct fw_address_region *region)
+{
+ struct fw_address_handler *other;
+ unsigned long flags;
+ int ret = -EBUSY;
+
+ spin_lock_irqsave(&address_handler_lock, flags);
+
+ handler->offset = region->start;
+ while (handler->offset + handler->length <= region->end) {
+ other =
+ lookup_overlapping_address_handler(&address_handler_list,
+ handler->offset,
+ handler->length);
+ if (other != NULL) {
+ handler->offset += other->length;
+ } else {
+ list_add_tail(&handler->link, &address_handler_list);
+ ret = 0;
+ break;
+ }
+ }
+
+ spin_unlock_irqrestore(&address_handler_lock, flags);
+
+ return ret;
+}
+
+EXPORT_SYMBOL(fw_core_add_address_handler);
+
+/**
+ * Deallocate a range of addresses allocated with fw_allocate. This
+ * will call the associated callback one last time with a the special
+ * tcode TCODE_DEALLOCATE, to let the client destroy the registered
+ * callback data. For convenience, the callback parameters offset and
+ * length are set to the start and the length respectively for the
+ * deallocated region, payload is set to NULL.
+ */
+
+void fw_core_remove_address_handler(struct fw_address_handler *handler)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&address_handler_lock, flags);
+ list_del(&handler->link);
+ spin_unlock_irqrestore(&address_handler_lock, flags);
+}
+
+EXPORT_SYMBOL(fw_core_remove_address_handler);
+
+struct fw_request {
+ struct fw_packet response;
+ int ack;
+ u32 length;
+ u32 data[0];
+};
+
+static void
+free_response_callback(struct fw_packet *packet,
+ struct fw_card *card, int status)
+{
+ struct fw_request *request;
+
+ request = container_of(packet, struct fw_request, response);
+ kfree(request);
+}
+
+static void
+fw_fill_response(struct fw_packet *response,
+ u32 *request, u32 *data, size_t length)
+{
+ int tcode, tlabel, extended_tcode, source, destination;
+
+ tcode = header_get_tcode(request[0]);
+ tlabel = header_get_tlabel(request[0]);
+ source = header_get_destination(request[0]);
+ destination = header_get_source(request[1]);
+ extended_tcode = header_get_extended_tcode(request[3]);
+
+ response->header[0] =
+ header_retry(RETRY_1) |
+ header_tlabel(tlabel) |
+ header_destination(destination);
+ response->header[1] = header_source(source);
+ response->header[2] = 0;
+
+ switch (tcode) {
+ case TCODE_WRITE_QUADLET_REQUEST:
+ case TCODE_WRITE_BLOCK_REQUEST:
+ response->header[0] |= header_tcode(TCODE_WRITE_RESPONSE);
+ response->header_length = 12;
+ response->payload_length = 0;
+ break;
+
+ case TCODE_READ_QUADLET_REQUEST:
+ response->header[0] |=
+ header_tcode(TCODE_READ_QUADLET_RESPONSE);
+ response->header[3] = 0;
+ response->header_length = 16;
+ response->payload_length = 0;
+ break;
+
+ case TCODE_READ_BLOCK_REQUEST:
+ case TCODE_LOCK_REQUEST:
+ response->header[0] |= header_tcode(tcode + 2);
+ response->header[3] =
+ header_data_length(length) |
+ header_extended_tcode(extended_tcode);
+ response->header_length = 16;
+ response->payload = data;
+ response->payload_length = length;
+ break;
+
+ default:
+ BUG();
+ return;
+ }
+}
+
+static struct fw_request *
+allocate_request(u32 *header, int ack,
+ int speed, int timestamp, int generation)
+{
+ struct fw_request *request;
+ u32 *data, length;
+ int request_tcode;
+
+ request_tcode = header_get_tcode(header[0]);
+ switch (request_tcode) {
+ case TCODE_WRITE_QUADLET_REQUEST:
+ data = &header[3];
+ length = 4;
+ break;
+
+ case TCODE_WRITE_BLOCK_REQUEST:
+ case TCODE_LOCK_REQUEST:
+ data = &header[4];
+ length = header_get_data_length(header[3]);
+ break;
+
+ case TCODE_READ_QUADLET_REQUEST:
+ data = NULL;
+ length = 4;
+ break;
+
+ case TCODE_READ_BLOCK_REQUEST:
+ data = NULL;
+ length = header_get_data_length(header[3]);
+ break;
+
+ default:
+ BUG();
+ return NULL;
+ }
+
+ request = kmalloc(sizeof *request + length, GFP_ATOMIC);
+ if (request == NULL)
+ return NULL;
+
+ request->response.speed = speed;
+ request->response.timestamp = timestamp;
+ request->response.generation = generation;
+ request->response.callback = free_response_callback;
+ request->ack = ack;
+ request->length = length;
+ if (data)
+ memcpy(request->data, data, length);
+
+ fw_fill_response(&request->response, header, request->data, length);
+
+ return request;
+}
+
+void
+fw_send_response(struct fw_card *card, struct fw_request *request, int rcode)
+{
+ int response_tcode;
+
+ /* Broadcast packets are reported as ACK_COMPLETE, so this
+ * check is sufficient to ensure we don't send response to
+ * broadcast packets or posted writes. */
+ if (request->ack != ACK_PENDING)
+ return;
+
+ request->response.header[1] |= header_rcode(rcode);
+ response_tcode = header_get_tcode(request->response.header[0]);
+ if (rcode != RCODE_COMPLETE)
+ /* Clear the data_length field. */
+ request->response.header[3] &= 0xffff;
+ else if (response_tcode == TCODE_READ_QUADLET_RESPONSE)
+ request->response.header[3] = request->data[0];
+
+ card->driver->send_response(card, &request->response);
+}
+
+EXPORT_SYMBOL(fw_send_response);
+
+void
+fw_core_handle_request(struct fw_card *card,
+ int speed, int ack, int timestamp,
+ int generation, u32 length, u32 *header)
+{
+ struct fw_address_handler *handler;
+ struct fw_request *request;
+ unsigned long long offset;
+ unsigned long flags;
+ int tcode, destination, source, t;
+
+ if (length > 2048) {
+ /* FIXME: send error response. */
+ return;
+ }
+
+ if (ack != ACK_PENDING && ack != ACK_COMPLETE)
+ return;
+
+ t = (timestamp & 0x1fff) + 4000;
+ if (t >= 8000)
+ t = (timestamp & ~0x1fff) + 0x2000 + t - 8000;
+ else
+ t = (timestamp & ~0x1fff) + t;
+
+ request = allocate_request(header, ack, speed, t, generation);
+ if (request == NULL) {
+ /* FIXME: send statically allocated busy packet. */
+ return;
+ }
+
+ offset =
+ ((unsigned long long)
+ header_get_offset_high(header[1]) << 32) | header[2];
+ tcode = header_get_tcode(header[0]);
+ destination = header_get_destination(header[0]);
+ source = header_get_source(header[0]);
+
+ spin_lock_irqsave(&address_handler_lock, flags);
+ handler = lookup_enclosing_address_handler(&address_handler_list,
+ offset, request->length);
+ spin_unlock_irqrestore(&address_handler_lock, flags);
+
+ /* FIXME: lookup the fw_node corresponding to the sender of
+ * this request and pass that to the address handler instead
+ * of the node ID. We may also want to move the address
+ * allocations to fw_node so we only do this callback if the
+ * upper layers registered it for this node. */
+
+ if (handler == NULL)
+ fw_send_response(card, request, RCODE_ADDRESS_ERROR);
+ else
+ handler->address_callback(card, request,
+ tcode, destination, source,
+ generation, speed, offset,
+ request->data, request->length,
+ handler->callback_data);
+}
+
+EXPORT_SYMBOL(fw_core_handle_request);
+
+void
+fw_core_handle_response(struct fw_card *card,
+ int speed, int ack, int timestamp,
+ u32 length, u32 *header)
+{
+ struct fw_transaction *t;
+ unsigned long flags;
+ u32 *data;
+ size_t data_length;
+ int tcode, tlabel, destination, source, rcode;
+
+ tcode = header_get_tcode(header[0]);
+ tlabel = header_get_tlabel(header[0]);
+ destination = header_get_destination(header[0]);
+ source = header_get_source(header[1]);
+ rcode = header_get_rcode(header[1]);
+
+ spin_lock_irqsave(&card->lock, flags);
+ list_for_each_entry(t, &card->transaction_list, link) {
+ if (t->node_id == source && t->tlabel == tlabel) {
+ list_del(&t->link);
+ card->tlabel_mask &= ~(1 << t->tlabel);
+ break;
+ }
+ }
+ spin_unlock_irqrestore(&card->lock, flags);
+
+ if (&t->link == &card->transaction_list) {
+ fw_notify("Unsolicited response\n");
+ return;
+ }
+
+ /* FIXME: sanity check packet, is length correct, does tcodes
+ * and addresses match. */
+
+ switch (tcode) {
+ case TCODE_READ_QUADLET_RESPONSE:
+ data = (u32 *) &header[3];
+ data_length = 4;
+ break;
+
+ case TCODE_WRITE_RESPONSE:
+ data = NULL;
+ data_length = 0;
+ break;
+
+ case TCODE_READ_BLOCK_RESPONSE:
+ case TCODE_LOCK_RESPONSE:
+ data = &header[4];
+ data_length = header_get_data_length(header[3]);
+ break;
+
+ default:
+ /* Should never happen, this is just to shut up gcc. */
+ data = NULL;
+ data_length = 0;
+ break;
+ }
+
+ t->callback(card, rcode, data, data_length, t->callback_data);
+}
+
+EXPORT_SYMBOL(fw_core_handle_response);
+
+MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
+MODULE_DESCRIPTION("Core IEEE1394 transaction logic");
+MODULE_LICENSE("GPL");
+
+static u32 vendor_textual_descriptor_data[] = {
+ /* textual descriptor leaf () */
+ 0x00080000,
+ 0x00000000,
+ 0x00000000,
+ 0x4c696e75, /* L i n u */
+ 0x78204669, /* x F i */
+ 0x72657769, /* r e w i */
+ 0x72652028, /* r e ( */
+ 0x4a554a55, /* J U J U */
+ 0x29000000, /* ) */
+};
+
+static struct fw_descriptor vendor_textual_descriptor = {
+ .length = ARRAY_SIZE(vendor_textual_descriptor_data),
+ .key = 0x81000000,
+ .data = vendor_textual_descriptor_data
+};
+
+struct bus_type fw_bus_type = {
+ .name = "fw",
+};
+
+static int __init fw_core_init(void)
+{
+ int retval;
+
+ retval = bus_register(&fw_bus_type);
+ if (retval < 0)
+ return retval;
+
+ /* Add the vendor textual descriptor. */
+ retval = fw_core_add_descriptor(&vendor_textual_descriptor);
+ BUG_ON(retval < 0);
+
+ return 0;
+}
+
+static void __exit fw_core_cleanup(void)
+{
+ bus_unregister(&fw_bus_type);
+}
+
+module_init(fw_core_init);
+module_exit(fw_core_cleanup);