linux/drivers/net/wireless/p54/main.c
Christian Lamparter be8d98eab8 p54: implement multicast filter
"For best CPU usage and power consumption, having as few
frames as possible percolate through the stack is
desirable. Hence, the hardware should filter as much
as possible."

Note: Not all firmwares include the multicast filter
feature and the stack does not filter them either.
The ARP filter on the other hand was dropped from the
patch since it does not work correctly:

Quote from: Max Filippov <jcmvbkbc@gmail.com>
<http://www.spinics.net/lists/linux-wireless/msg67466.html>
"In the ARP case, when there's no other traffic on p54spi,
all ARP requests are dropped. But if there's some egress
traffic from p54spi, filter seems to work correctly:
only ARP requests that match filter pass through.

In the multicast case filter seems to work correctly, but
it treats broadcast as subject to that filtering too. By
default only 01:00:5e:00:00:01 gets into priv->mc_maclist,
so we miss all broadcasts.

These two filters seem to interfere:
- if we set ARP filter and multicast filter without bc
	=>  we miss all ARPs if there's no egress traffic;
- if we set ARP filter and multicast filter with bc or
	don't set mc filter at all => we get all ARPs.

This effect does not depend on filter setup order."

Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Tested-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2011-04-26 15:50:30 -04:00

754 lines
18 KiB
C

/*
* mac80211 glue code for mac80211 Prism54 drivers
*
* Copyright (c) 2006, Michael Wu <flamingice@sourmilk.net>
* Copyright (c) 2007-2009, Christian Lamparter <chunkeey@web.de>
* Copyright 2008, Johannes Berg <johannes@sipsolutions.net>
*
* Based on:
* - the islsm (softmac prism54) driver, which is:
* Copyright 2004-2006 Jean-Baptiste Note <jbnote@gmail.com>, et al.
* - stlc45xx driver
* Copyright (C) 2008 Nokia Corporation and/or its subsidiary(-ies).
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/firmware.h>
#include <linux/etherdevice.h>
#include <net/mac80211.h>
#include "p54.h"
#include "lmac.h"
static int modparam_nohwcrypt;
module_param_named(nohwcrypt, modparam_nohwcrypt, bool, S_IRUGO);
MODULE_PARM_DESC(nohwcrypt, "Disable hardware encryption.");
MODULE_AUTHOR("Michael Wu <flamingice@sourmilk.net>");
MODULE_DESCRIPTION("Softmac Prism54 common code");
MODULE_LICENSE("GPL");
MODULE_ALIAS("prism54common");
static int p54_sta_add_remove(struct ieee80211_hw *hw,
struct ieee80211_vif *vif,
struct ieee80211_sta *sta)
{
struct p54_common *priv = hw->priv;
/*
* Notify the firmware that we don't want or we don't
* need to buffer frames for this station anymore.
*/
p54_sta_unlock(priv, sta->addr);
return 0;
}
static void p54_sta_notify(struct ieee80211_hw *dev, struct ieee80211_vif *vif,
enum sta_notify_cmd notify_cmd,
struct ieee80211_sta *sta)
{
struct p54_common *priv = dev->priv;
switch (notify_cmd) {
case STA_NOTIFY_AWAKE:
/* update the firmware's filter table */
p54_sta_unlock(priv, sta->addr);
break;
default:
break;
}
}
static int p54_set_tim(struct ieee80211_hw *dev, struct ieee80211_sta *sta,
bool set)
{
struct p54_common *priv = dev->priv;
return p54_update_beacon_tim(priv, sta->aid, set);
}
u8 *p54_find_ie(struct sk_buff *skb, u8 ie)
{
struct ieee80211_mgmt *mgmt = (void *)skb->data;
u8 *pos, *end;
if (skb->len <= sizeof(mgmt))
return NULL;
pos = (u8 *)mgmt->u.beacon.variable;
end = skb->data + skb->len;
while (pos < end) {
if (pos + 2 + pos[1] > end)
return NULL;
if (pos[0] == ie)
return pos;
pos += 2 + pos[1];
}
return NULL;
}
static int p54_beacon_format_ie_tim(struct sk_buff *skb)
{
/*
* the good excuse for this mess is ... the firmware.
* The dummy TIM MUST be at the end of the beacon frame,
* because it'll be overwritten!
*/
u8 *tim;
u8 dtim_len;
u8 dtim_period;
u8 *next;
tim = p54_find_ie(skb, WLAN_EID_TIM);
if (!tim)
return 0;
dtim_len = tim[1];
dtim_period = tim[3];
next = tim + 2 + dtim_len;
if (dtim_len < 3)
return -EINVAL;
memmove(tim, next, skb_tail_pointer(skb) - next);
tim = skb_tail_pointer(skb) - (dtim_len + 2);
/* add the dummy at the end */
tim[0] = WLAN_EID_TIM;
tim[1] = 3;
tim[2] = 0;
tim[3] = dtim_period;
tim[4] = 0;
if (dtim_len > 3)
skb_trim(skb, skb->len - (dtim_len - 3));
return 0;
}
static int p54_beacon_update(struct p54_common *priv,
struct ieee80211_vif *vif)
{
struct sk_buff *beacon;
int ret;
beacon = ieee80211_beacon_get(priv->hw, vif);
if (!beacon)
return -ENOMEM;
ret = p54_beacon_format_ie_tim(beacon);
if (ret)
return ret;
/*
* During operation, the firmware takes care of beaconing.
* The driver only needs to upload a new beacon template, once
* the template was changed by the stack or userspace.
*
* LMAC API 3.2.2 also specifies that the driver does not need
* to cancel the old beacon template by hand, instead the firmware
* will release the previous one through the feedback mechanism.
*/
p54_tx_80211(priv->hw, beacon);
priv->tsf_high32 = 0;
priv->tsf_low32 = 0;
return 0;
}
static int p54_start(struct ieee80211_hw *dev)
{
struct p54_common *priv = dev->priv;
int err;
mutex_lock(&priv->conf_mutex);
err = priv->open(dev);
if (err)
goto out;
P54_SET_QUEUE(priv->qos_params[0], 0x0002, 0x0003, 0x0007, 47);
P54_SET_QUEUE(priv->qos_params[1], 0x0002, 0x0007, 0x000f, 94);
P54_SET_QUEUE(priv->qos_params[2], 0x0003, 0x000f, 0x03ff, 0);
P54_SET_QUEUE(priv->qos_params[3], 0x0007, 0x000f, 0x03ff, 0);
err = p54_set_edcf(priv);
if (err)
goto out;
memset(priv->bssid, ~0, ETH_ALEN);
priv->mode = NL80211_IFTYPE_MONITOR;
err = p54_setup_mac(priv);
if (err) {
priv->mode = NL80211_IFTYPE_UNSPECIFIED;
goto out;
}
ieee80211_queue_delayed_work(dev, &priv->work, 0);
priv->softled_state = 0;
err = p54_set_leds(priv);
out:
mutex_unlock(&priv->conf_mutex);
return err;
}
static void p54_stop(struct ieee80211_hw *dev)
{
struct p54_common *priv = dev->priv;
int i;
mutex_lock(&priv->conf_mutex);
priv->mode = NL80211_IFTYPE_UNSPECIFIED;
priv->softled_state = 0;
p54_set_leds(priv);
cancel_delayed_work_sync(&priv->work);
priv->stop(dev);
skb_queue_purge(&priv->tx_pending);
skb_queue_purge(&priv->tx_queue);
for (i = 0; i < P54_QUEUE_NUM; i++) {
priv->tx_stats[i].count = 0;
priv->tx_stats[i].len = 0;
}
priv->beacon_req_id = cpu_to_le32(0);
priv->tsf_high32 = priv->tsf_low32 = 0;
mutex_unlock(&priv->conf_mutex);
}
static int p54_add_interface(struct ieee80211_hw *dev,
struct ieee80211_vif *vif)
{
struct p54_common *priv = dev->priv;
mutex_lock(&priv->conf_mutex);
if (priv->mode != NL80211_IFTYPE_MONITOR) {
mutex_unlock(&priv->conf_mutex);
return -EOPNOTSUPP;
}
priv->vif = vif;
switch (vif->type) {
case NL80211_IFTYPE_STATION:
case NL80211_IFTYPE_ADHOC:
case NL80211_IFTYPE_AP:
case NL80211_IFTYPE_MESH_POINT:
priv->mode = vif->type;
break;
default:
mutex_unlock(&priv->conf_mutex);
return -EOPNOTSUPP;
}
memcpy(priv->mac_addr, vif->addr, ETH_ALEN);
p54_setup_mac(priv);
mutex_unlock(&priv->conf_mutex);
return 0;
}
static void p54_remove_interface(struct ieee80211_hw *dev,
struct ieee80211_vif *vif)
{
struct p54_common *priv = dev->priv;
mutex_lock(&priv->conf_mutex);
priv->vif = NULL;
/*
* LMAC API 3.2.2 states that any active beacon template must be
* canceled by the driver before attempting a mode transition.
*/
if (le32_to_cpu(priv->beacon_req_id) != 0) {
p54_tx_cancel(priv, priv->beacon_req_id);
wait_for_completion_interruptible_timeout(&priv->beacon_comp, HZ);
}
priv->mode = NL80211_IFTYPE_MONITOR;
memset(priv->mac_addr, 0, ETH_ALEN);
memset(priv->bssid, 0, ETH_ALEN);
p54_setup_mac(priv);
mutex_unlock(&priv->conf_mutex);
}
static int p54_config(struct ieee80211_hw *dev, u32 changed)
{
int ret = 0;
struct p54_common *priv = dev->priv;
struct ieee80211_conf *conf = &dev->conf;
mutex_lock(&priv->conf_mutex);
if (changed & IEEE80211_CONF_CHANGE_POWER)
priv->output_power = conf->power_level << 2;
if (changed & IEEE80211_CONF_CHANGE_CHANNEL) {
ret = p54_scan(priv, P54_SCAN_EXIT, 0);
if (ret)
goto out;
}
if (changed & IEEE80211_CONF_CHANGE_PS) {
ret = p54_set_ps(priv);
if (ret)
goto out;
}
if (changed & IEEE80211_CONF_CHANGE_IDLE) {
ret = p54_setup_mac(priv);
if (ret)
goto out;
}
out:
mutex_unlock(&priv->conf_mutex);
return ret;
}
static u64 p54_prepare_multicast(struct ieee80211_hw *dev,
struct netdev_hw_addr_list *mc_list)
{
struct p54_common *priv = dev->priv;
struct netdev_hw_addr *ha;
int i;
BUILD_BUG_ON(ARRAY_SIZE(priv->mc_maclist) !=
ARRAY_SIZE(((struct p54_group_address_table *)NULL)->mac_list));
/*
* The first entry is reserved for the global broadcast MAC.
* Otherwise the firmware will drop it and ARP will no longer work.
*/
i = 1;
priv->mc_maclist_num = netdev_hw_addr_list_count(mc_list) + i;
netdev_hw_addr_list_for_each(ha, mc_list) {
memcpy(&priv->mc_maclist[i], ha->addr, ETH_ALEN);
i++;
if (i >= ARRAY_SIZE(priv->mc_maclist))
break;
}
return 1; /* update */
}
static void p54_configure_filter(struct ieee80211_hw *dev,
unsigned int changed_flags,
unsigned int *total_flags,
u64 multicast)
{
struct p54_common *priv = dev->priv;
*total_flags &= FIF_PROMISC_IN_BSS |
FIF_ALLMULTI |
FIF_OTHER_BSS;
priv->filter_flags = *total_flags;
if (changed_flags & (FIF_PROMISC_IN_BSS | FIF_OTHER_BSS))
p54_setup_mac(priv);
if (changed_flags & FIF_ALLMULTI || multicast)
p54_set_groupfilter(priv);
}
static int p54_conf_tx(struct ieee80211_hw *dev, u16 queue,
const struct ieee80211_tx_queue_params *params)
{
struct p54_common *priv = dev->priv;
int ret;
mutex_lock(&priv->conf_mutex);
if (queue < dev->queues) {
P54_SET_QUEUE(priv->qos_params[queue], params->aifs,
params->cw_min, params->cw_max, params->txop);
ret = p54_set_edcf(priv);
} else
ret = -EINVAL;
mutex_unlock(&priv->conf_mutex);
return ret;
}
static void p54_work(struct work_struct *work)
{
struct p54_common *priv = container_of(work, struct p54_common,
work.work);
if (unlikely(priv->mode == NL80211_IFTYPE_UNSPECIFIED))
return ;
/*
* TODO: walk through tx_queue and do the following tasks
* 1. initiate bursts.
* 2. cancel stuck frames / reset the device if necessary.
*/
p54_fetch_statistics(priv);
}
static int p54_get_stats(struct ieee80211_hw *dev,
struct ieee80211_low_level_stats *stats)
{
struct p54_common *priv = dev->priv;
memcpy(stats, &priv->stats, sizeof(*stats));
return 0;
}
static void p54_bss_info_changed(struct ieee80211_hw *dev,
struct ieee80211_vif *vif,
struct ieee80211_bss_conf *info,
u32 changed)
{
struct p54_common *priv = dev->priv;
mutex_lock(&priv->conf_mutex);
if (changed & BSS_CHANGED_BSSID) {
memcpy(priv->bssid, info->bssid, ETH_ALEN);
p54_setup_mac(priv);
}
if (changed & BSS_CHANGED_BEACON) {
p54_scan(priv, P54_SCAN_EXIT, 0);
p54_setup_mac(priv);
p54_beacon_update(priv, vif);
p54_set_edcf(priv);
}
if (changed & (BSS_CHANGED_ERP_SLOT | BSS_CHANGED_BEACON)) {
priv->use_short_slot = info->use_short_slot;
p54_set_edcf(priv);
}
if (changed & BSS_CHANGED_BASIC_RATES) {
if (dev->conf.channel->band == IEEE80211_BAND_5GHZ)
priv->basic_rate_mask = (info->basic_rates << 4);
else
priv->basic_rate_mask = info->basic_rates;
p54_setup_mac(priv);
if (priv->fw_var >= 0x500)
p54_scan(priv, P54_SCAN_EXIT, 0);
}
if (changed & BSS_CHANGED_ASSOC) {
if (info->assoc) {
priv->aid = info->aid;
priv->wakeup_timer = info->beacon_int *
info->dtim_period * 5;
p54_setup_mac(priv);
} else {
priv->wakeup_timer = 500;
priv->aid = 0;
}
}
mutex_unlock(&priv->conf_mutex);
}
static int p54_set_key(struct ieee80211_hw *dev, enum set_key_cmd cmd,
struct ieee80211_vif *vif, struct ieee80211_sta *sta,
struct ieee80211_key_conf *key)
{
struct p54_common *priv = dev->priv;
int slot, ret = 0;
u8 algo = 0;
u8 *addr = NULL;
if (modparam_nohwcrypt)
return -EOPNOTSUPP;
mutex_lock(&priv->conf_mutex);
if (cmd == SET_KEY) {
switch (key->cipher) {
case WLAN_CIPHER_SUITE_TKIP:
if (!(priv->privacy_caps & (BR_DESC_PRIV_CAP_MICHAEL |
BR_DESC_PRIV_CAP_TKIP))) {
ret = -EOPNOTSUPP;
goto out_unlock;
}
key->flags |= IEEE80211_KEY_FLAG_GENERATE_IV;
algo = P54_CRYPTO_TKIPMICHAEL;
break;
case WLAN_CIPHER_SUITE_WEP40:
case WLAN_CIPHER_SUITE_WEP104:
if (!(priv->privacy_caps & BR_DESC_PRIV_CAP_WEP)) {
ret = -EOPNOTSUPP;
goto out_unlock;
}
key->flags |= IEEE80211_KEY_FLAG_GENERATE_IV;
algo = P54_CRYPTO_WEP;
break;
case WLAN_CIPHER_SUITE_CCMP:
if (!(priv->privacy_caps & BR_DESC_PRIV_CAP_AESCCMP)) {
ret = -EOPNOTSUPP;
goto out_unlock;
}
key->flags |= IEEE80211_KEY_FLAG_GENERATE_IV;
algo = P54_CRYPTO_AESCCMP;
break;
default:
ret = -EOPNOTSUPP;
goto out_unlock;
}
slot = bitmap_find_free_region(priv->used_rxkeys,
priv->rx_keycache_size, 0);
if (slot < 0) {
/*
* The device supports the choosen algorithm, but the
* firmware does not provide enough key slots to store
* all of them.
* But encryption offload for outgoing frames is always
* possible, so we just pretend that the upload was
* successful and do the decryption in software.
*/
/* mark the key as invalid. */
key->hw_key_idx = 0xff;
goto out_unlock;
}
} else {
slot = key->hw_key_idx;
if (slot == 0xff) {
/* This key was not uploaded into the rx key cache. */
goto out_unlock;
}
bitmap_release_region(priv->used_rxkeys, slot, 0);
algo = 0;
}
if (sta)
addr = sta->addr;
ret = p54_upload_key(priv, algo, slot, key->keyidx,
key->keylen, addr, key->key);
if (ret) {
bitmap_release_region(priv->used_rxkeys, slot, 0);
ret = -EOPNOTSUPP;
goto out_unlock;
}
key->hw_key_idx = slot;
out_unlock:
mutex_unlock(&priv->conf_mutex);
return ret;
}
static int p54_get_survey(struct ieee80211_hw *dev, int idx,
struct survey_info *survey)
{
struct p54_common *priv = dev->priv;
struct ieee80211_conf *conf = &dev->conf;
if (idx != 0)
return -ENOENT;
survey->channel = conf->channel;
survey->filled = SURVEY_INFO_NOISE_DBM;
survey->noise = clamp_t(s8, priv->noise, -128, 127);
return 0;
}
static unsigned int p54_flush_count(struct p54_common *priv)
{
unsigned int total = 0, i;
BUILD_BUG_ON(P54_QUEUE_NUM > ARRAY_SIZE(priv->tx_stats));
/*
* Because the firmware has the sole control over any frames
* in the P54_QUEUE_BEACON or P54_QUEUE_SCAN queues, they
* don't really count as pending or active.
*/
for (i = P54_QUEUE_MGMT; i < P54_QUEUE_NUM; i++)
total += priv->tx_stats[i].len;
return total;
}
static void p54_flush(struct ieee80211_hw *dev, bool drop)
{
struct p54_common *priv = dev->priv;
unsigned int total, i;
/*
* Currently, it wouldn't really matter if we wait for one second
* or 15 minutes. But once someone gets around and completes the
* TODOs [ancel stuck frames / reset device] in p54_work, it will
* suddenly make sense to wait that long.
*/
i = P54_STATISTICS_UPDATE * 2 / 20;
/*
* In this case no locking is required because as we speak the
* queues have already been stopped and no new frames can sneak
* up from behind.
*/
while ((total = p54_flush_count(priv) && i--)) {
/* waste time */
msleep(20);
}
WARN(total, "tx flush timeout, unresponsive firmware");
}
static void p54_set_coverage_class(struct ieee80211_hw *dev, u8 coverage_class)
{
struct p54_common *priv = dev->priv;
mutex_lock(&priv->conf_mutex);
/* support all coverage class values as in 802.11-2007 Table 7-27 */
priv->coverage_class = clamp_t(u8, coverage_class, 0, 31);
p54_set_edcf(priv);
mutex_unlock(&priv->conf_mutex);
}
static const struct ieee80211_ops p54_ops = {
.tx = p54_tx_80211,
.start = p54_start,
.stop = p54_stop,
.add_interface = p54_add_interface,
.remove_interface = p54_remove_interface,
.set_tim = p54_set_tim,
.sta_notify = p54_sta_notify,
.sta_add = p54_sta_add_remove,
.sta_remove = p54_sta_add_remove,
.set_key = p54_set_key,
.config = p54_config,
.flush = p54_flush,
.bss_info_changed = p54_bss_info_changed,
.prepare_multicast = p54_prepare_multicast,
.configure_filter = p54_configure_filter,
.conf_tx = p54_conf_tx,
.get_stats = p54_get_stats,
.get_survey = p54_get_survey,
.set_coverage_class = p54_set_coverage_class,
};
struct ieee80211_hw *p54_init_common(size_t priv_data_len)
{
struct ieee80211_hw *dev;
struct p54_common *priv;
dev = ieee80211_alloc_hw(priv_data_len, &p54_ops);
if (!dev)
return NULL;
priv = dev->priv;
priv->hw = dev;
priv->mode = NL80211_IFTYPE_UNSPECIFIED;
priv->basic_rate_mask = 0x15f;
spin_lock_init(&priv->tx_stats_lock);
skb_queue_head_init(&priv->tx_queue);
skb_queue_head_init(&priv->tx_pending);
dev->flags = IEEE80211_HW_RX_INCLUDES_FCS |
IEEE80211_HW_SIGNAL_DBM |
IEEE80211_HW_SUPPORTS_PS |
IEEE80211_HW_PS_NULLFUNC_STACK |
IEEE80211_HW_BEACON_FILTER |
IEEE80211_HW_REPORTS_TX_ACK_STATUS;
dev->wiphy->interface_modes = BIT(NL80211_IFTYPE_STATION) |
BIT(NL80211_IFTYPE_ADHOC) |
BIT(NL80211_IFTYPE_AP) |
BIT(NL80211_IFTYPE_MESH_POINT);
dev->channel_change_time = 1000; /* TODO: find actual value */
priv->beacon_req_id = cpu_to_le32(0);
priv->tx_stats[P54_QUEUE_BEACON].limit = 1;
priv->tx_stats[P54_QUEUE_FWSCAN].limit = 1;
priv->tx_stats[P54_QUEUE_MGMT].limit = 3;
priv->tx_stats[P54_QUEUE_CAB].limit = 3;
priv->tx_stats[P54_QUEUE_DATA].limit = 5;
dev->queues = 1;
priv->noise = -94;
/*
* We support at most 8 tries no matter which rate they're at,
* we cannot support max_rates * max_rate_tries as we set it
* here, but setting it correctly to 4/2 or so would limit us
* artificially if the RC algorithm wants just two rates, so
* let's say 4/7, we'll redistribute it at TX time, see the
* comments there.
*/
dev->max_rates = 4;
dev->max_rate_tries = 7;
dev->extra_tx_headroom = sizeof(struct p54_hdr) + 4 +
sizeof(struct p54_tx_data);
/*
* For now, disable PS by default because it affects
* link stability significantly.
*/
dev->wiphy->flags &= ~WIPHY_FLAG_PS_ON_BY_DEFAULT;
mutex_init(&priv->conf_mutex);
mutex_init(&priv->eeprom_mutex);
init_completion(&priv->eeprom_comp);
init_completion(&priv->beacon_comp);
INIT_DELAYED_WORK(&priv->work, p54_work);
memset(&priv->mc_maclist[0], ~0, ETH_ALEN);
return dev;
}
EXPORT_SYMBOL_GPL(p54_init_common);
int p54_register_common(struct ieee80211_hw *dev, struct device *pdev)
{
struct p54_common __maybe_unused *priv = dev->priv;
int err;
err = ieee80211_register_hw(dev);
if (err) {
dev_err(pdev, "Cannot register device (%d).\n", err);
return err;
}
#ifdef CONFIG_P54_LEDS
err = p54_init_leds(priv);
if (err)
return err;
#endif /* CONFIG_P54_LEDS */
dev_info(pdev, "is registered as '%s'\n", wiphy_name(dev->wiphy));
return 0;
}
EXPORT_SYMBOL_GPL(p54_register_common);
void p54_free_common(struct ieee80211_hw *dev)
{
struct p54_common *priv = dev->priv;
unsigned int i;
for (i = 0; i < IEEE80211_NUM_BANDS; i++)
kfree(priv->band_table[i]);
kfree(priv->iq_autocal);
kfree(priv->output_limit);
kfree(priv->curve_data);
kfree(priv->rssi_db);
kfree(priv->used_rxkeys);
priv->iq_autocal = NULL;
priv->output_limit = NULL;
priv->curve_data = NULL;
priv->rssi_db = NULL;
priv->used_rxkeys = NULL;
ieee80211_free_hw(dev);
}
EXPORT_SYMBOL_GPL(p54_free_common);
void p54_unregister_common(struct ieee80211_hw *dev)
{
struct p54_common *priv = dev->priv;
#ifdef CONFIG_P54_LEDS
p54_unregister_leds(priv);
#endif /* CONFIG_P54_LEDS */
ieee80211_unregister_hw(dev);
mutex_destroy(&priv->conf_mutex);
mutex_destroy(&priv->eeprom_mutex);
}
EXPORT_SYMBOL_GPL(p54_unregister_common);