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path: root/drivers/net/wireless/zd1211rw/zd_mac.c
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Diffstat (limited to 'drivers/net/wireless/zd1211rw/zd_mac.c')
-rw-r--r--drivers/net/wireless/zd1211rw/zd_mac.c404
1 files changed, 248 insertions, 156 deletions
diff --git a/drivers/net/wireless/zd1211rw/zd_mac.c b/drivers/net/wireless/zd1211rw/zd_mac.c
index 5e4f4b707375..44f3cfd4cc1d 100644
--- a/drivers/net/wireless/zd1211rw/zd_mac.c
+++ b/drivers/net/wireless/zd1211rw/zd_mac.c
@@ -32,6 +32,8 @@
static void ieee_init(struct ieee80211_device *ieee);
static void softmac_init(struct ieee80211softmac_device *sm);
+static void set_rts_cts_work(void *d);
+static void set_basic_rates_work(void *d);
static void housekeeping_init(struct zd_mac *mac);
static void housekeeping_enable(struct zd_mac *mac);
@@ -46,6 +48,8 @@ int zd_mac_init(struct zd_mac *mac,
memset(mac, 0, sizeof(*mac));
spin_lock_init(&mac->lock);
mac->netdev = netdev;
+ INIT_WORK(&mac->set_rts_cts_work, set_rts_cts_work, mac);
+ INIT_WORK(&mac->set_basic_rates_work, set_basic_rates_work, mac);
ieee_init(ieee);
softmac_init(ieee80211_priv(netdev));
@@ -213,6 +217,13 @@ int zd_mac_stop(struct net_device *netdev)
housekeeping_disable(mac);
ieee80211softmac_stop(netdev);
+ /* Ensure no work items are running or queued from this point */
+ cancel_delayed_work(&mac->set_rts_cts_work);
+ cancel_delayed_work(&mac->set_basic_rates_work);
+ flush_workqueue(zd_workqueue);
+ mac->updating_rts_rate = 0;
+ mac->updating_basic_rates = 0;
+
zd_chip_disable_hwint(chip);
zd_chip_switch_radio_off(chip);
zd_chip_disable_int(chip);
@@ -286,6 +297,186 @@ u8 zd_mac_get_regdomain(struct zd_mac *mac)
return regdomain;
}
+/* Fallback to lowest rate, if rate is unknown. */
+static u8 rate_to_zd_rate(u8 rate)
+{
+ switch (rate) {
+ case IEEE80211_CCK_RATE_2MB:
+ return ZD_CCK_RATE_2M;
+ case IEEE80211_CCK_RATE_5MB:
+ return ZD_CCK_RATE_5_5M;
+ case IEEE80211_CCK_RATE_11MB:
+ return ZD_CCK_RATE_11M;
+ case IEEE80211_OFDM_RATE_6MB:
+ return ZD_OFDM_RATE_6M;
+ case IEEE80211_OFDM_RATE_9MB:
+ return ZD_OFDM_RATE_9M;
+ case IEEE80211_OFDM_RATE_12MB:
+ return ZD_OFDM_RATE_12M;
+ case IEEE80211_OFDM_RATE_18MB:
+ return ZD_OFDM_RATE_18M;
+ case IEEE80211_OFDM_RATE_24MB:
+ return ZD_OFDM_RATE_24M;
+ case IEEE80211_OFDM_RATE_36MB:
+ return ZD_OFDM_RATE_36M;
+ case IEEE80211_OFDM_RATE_48MB:
+ return ZD_OFDM_RATE_48M;
+ case IEEE80211_OFDM_RATE_54MB:
+ return ZD_OFDM_RATE_54M;
+ }
+ return ZD_CCK_RATE_1M;
+}
+
+static u16 rate_to_cr_rate(u8 rate)
+{
+ switch (rate) {
+ case IEEE80211_CCK_RATE_2MB:
+ return CR_RATE_1M;
+ case IEEE80211_CCK_RATE_5MB:
+ return CR_RATE_5_5M;
+ case IEEE80211_CCK_RATE_11MB:
+ return CR_RATE_11M;
+ case IEEE80211_OFDM_RATE_6MB:
+ return CR_RATE_6M;
+ case IEEE80211_OFDM_RATE_9MB:
+ return CR_RATE_9M;
+ case IEEE80211_OFDM_RATE_12MB:
+ return CR_RATE_12M;
+ case IEEE80211_OFDM_RATE_18MB:
+ return CR_RATE_18M;
+ case IEEE80211_OFDM_RATE_24MB:
+ return CR_RATE_24M;
+ case IEEE80211_OFDM_RATE_36MB:
+ return CR_RATE_36M;
+ case IEEE80211_OFDM_RATE_48MB:
+ return CR_RATE_48M;
+ case IEEE80211_OFDM_RATE_54MB:
+ return CR_RATE_54M;
+ }
+ return CR_RATE_1M;
+}
+
+static void try_enable_tx(struct zd_mac *mac)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&mac->lock, flags);
+ if (mac->updating_rts_rate == 0 && mac->updating_basic_rates == 0)
+ netif_wake_queue(mac->netdev);
+ spin_unlock_irqrestore(&mac->lock, flags);
+}
+
+static void set_rts_cts_work(void *d)
+{
+ struct zd_mac *mac = d;
+ unsigned long flags;
+ u8 rts_rate;
+ unsigned int short_preamble;
+
+ mutex_lock(&mac->chip.mutex);
+
+ spin_lock_irqsave(&mac->lock, flags);
+ mac->updating_rts_rate = 0;
+ rts_rate = mac->rts_rate;
+ short_preamble = mac->short_preamble;
+ spin_unlock_irqrestore(&mac->lock, flags);
+
+ zd_chip_set_rts_cts_rate_locked(&mac->chip, rts_rate, short_preamble);
+ mutex_unlock(&mac->chip.mutex);
+
+ try_enable_tx(mac);
+}
+
+static void set_basic_rates_work(void *d)
+{
+ struct zd_mac *mac = d;
+ unsigned long flags;
+ u16 basic_rates;
+
+ mutex_lock(&mac->chip.mutex);
+
+ spin_lock_irqsave(&mac->lock, flags);
+ mac->updating_basic_rates = 0;
+ basic_rates = mac->basic_rates;
+ spin_unlock_irqrestore(&mac->lock, flags);
+
+ zd_chip_set_basic_rates_locked(&mac->chip, basic_rates);
+ mutex_unlock(&mac->chip.mutex);
+
+ try_enable_tx(mac);
+}
+
+static void bssinfo_change(struct net_device *netdev, u32 changes)
+{
+ struct zd_mac *mac = zd_netdev_mac(netdev);
+ struct ieee80211softmac_device *softmac = ieee80211_priv(netdev);
+ struct ieee80211softmac_bss_info *bssinfo = &softmac->bssinfo;
+ int need_set_rts_cts = 0;
+ int need_set_rates = 0;
+ u16 basic_rates;
+ unsigned long flags;
+
+ dev_dbg_f(zd_mac_dev(mac), "changes: %x\n", changes);
+
+ if (changes & IEEE80211SOFTMAC_BSSINFOCHG_SHORT_PREAMBLE) {
+ spin_lock_irqsave(&mac->lock, flags);
+ mac->short_preamble = bssinfo->short_preamble;
+ spin_unlock_irqrestore(&mac->lock, flags);
+ need_set_rts_cts = 1;
+ }
+
+ if (changes & IEEE80211SOFTMAC_BSSINFOCHG_RATES) {
+ /* Set RTS rate to highest available basic rate */
+ u8 rate = ieee80211softmac_highest_supported_rate(softmac,
+ &bssinfo->supported_rates, 1);
+ rate = rate_to_zd_rate(rate);
+
+ spin_lock_irqsave(&mac->lock, flags);
+ if (rate != mac->rts_rate) {
+ mac->rts_rate = rate;
+ need_set_rts_cts = 1;
+ }
+ spin_unlock_irqrestore(&mac->lock, flags);
+
+ /* Set basic rates */
+ need_set_rates = 1;
+ if (bssinfo->supported_rates.count == 0) {
+ /* Allow the device to be flexible */
+ basic_rates = CR_RATES_80211B | CR_RATES_80211G;
+ } else {
+ int i = 0;
+ basic_rates = 0;
+
+ for (i = 0; i < bssinfo->supported_rates.count; i++) {
+ u16 rate = bssinfo->supported_rates.rates[i];
+ if ((rate & IEEE80211_BASIC_RATE_MASK) == 0)
+ continue;
+
+ rate &= ~IEEE80211_BASIC_RATE_MASK;
+ basic_rates |= rate_to_cr_rate(rate);
+ }
+ }
+ spin_lock_irqsave(&mac->lock, flags);
+ mac->basic_rates = basic_rates;
+ spin_unlock_irqrestore(&mac->lock, flags);
+ }
+
+ /* Schedule any changes we made above */
+
+ spin_lock_irqsave(&mac->lock, flags);
+ if (need_set_rts_cts && !mac->updating_rts_rate) {
+ mac->updating_rts_rate = 1;
+ netif_stop_queue(mac->netdev);
+ queue_work(zd_workqueue, &mac->set_rts_cts_work);
+ }
+ if (need_set_rates && !mac->updating_basic_rates) {
+ mac->updating_basic_rates = 1;
+ netif_stop_queue(mac->netdev);
+ queue_work(zd_workqueue, &mac->set_basic_rates_work);
+ }
+ spin_unlock_irqrestore(&mac->lock, flags);
+}
+
static void set_channel(struct net_device *netdev, u8 channel)
{
struct zd_mac *mac = zd_netdev_mac(netdev);
@@ -295,7 +486,6 @@ static void set_channel(struct net_device *netdev, u8 channel)
zd_chip_set_channel(&mac->chip, channel);
}
-/* TODO: Should not work in Managed mode. */
int zd_mac_request_channel(struct zd_mac *mac, u8 channel)
{
unsigned long lock_flags;
@@ -317,31 +507,22 @@ int zd_mac_request_channel(struct zd_mac *mac, u8 channel)
return 0;
}
-int zd_mac_get_channel(struct zd_mac *mac, u8 *channel, u8 *flags)
+u8 zd_mac_get_channel(struct zd_mac *mac)
{
- struct ieee80211_device *ieee = zd_mac_to_ieee80211(mac);
+ u8 channel = zd_chip_get_channel(&mac->chip);
- *channel = zd_chip_get_channel(&mac->chip);
- if (ieee->iw_mode != IW_MODE_INFRA) {
- spin_lock_irq(&mac->lock);
- *flags = *channel == mac->requested_channel ?
- MAC_FIXED_CHANNEL : 0;
- spin_unlock(&mac->lock);
- } else {
- *flags = 0;
- }
- dev_dbg_f(zd_mac_dev(mac), "channel %u flags %u\n", *channel, *flags);
- return 0;
+ dev_dbg_f(zd_mac_dev(mac), "channel %u\n", channel);
+ return channel;
}
/* If wrong rate is given, we are falling back to the slowest rate: 1MBit/s */
-static u8 cs_typed_rate(u8 cs_rate)
+static u8 zd_rate_typed(u8 zd_rate)
{
static const u8 typed_rates[16] = {
- [ZD_CS_CCK_RATE_1M] = ZD_CS_CCK|ZD_CS_CCK_RATE_1M,
- [ZD_CS_CCK_RATE_2M] = ZD_CS_CCK|ZD_CS_CCK_RATE_2M,
- [ZD_CS_CCK_RATE_5_5M] = ZD_CS_CCK|ZD_CS_CCK_RATE_5_5M,
- [ZD_CS_CCK_RATE_11M] = ZD_CS_CCK|ZD_CS_CCK_RATE_11M,
+ [ZD_CCK_RATE_1M] = ZD_CS_CCK|ZD_CCK_RATE_1M,
+ [ZD_CCK_RATE_2M] = ZD_CS_CCK|ZD_CCK_RATE_2M,
+ [ZD_CCK_RATE_5_5M] = ZD_CS_CCK|ZD_CCK_RATE_5_5M,
+ [ZD_CCK_RATE_11M] = ZD_CS_CCK|ZD_CCK_RATE_11M,
[ZD_OFDM_RATE_6M] = ZD_CS_OFDM|ZD_OFDM_RATE_6M,
[ZD_OFDM_RATE_9M] = ZD_CS_OFDM|ZD_OFDM_RATE_9M,
[ZD_OFDM_RATE_12M] = ZD_CS_OFDM|ZD_OFDM_RATE_12M,
@@ -353,37 +534,7 @@ static u8 cs_typed_rate(u8 cs_rate)
};
ZD_ASSERT(ZD_CS_RATE_MASK == 0x0f);
- return typed_rates[cs_rate & ZD_CS_RATE_MASK];
-}
-
-/* Fallback to lowest rate, if rate is unknown. */
-static u8 rate_to_cs_rate(u8 rate)
-{
- switch (rate) {
- case IEEE80211_CCK_RATE_2MB:
- return ZD_CS_CCK_RATE_2M;
- case IEEE80211_CCK_RATE_5MB:
- return ZD_CS_CCK_RATE_5_5M;
- case IEEE80211_CCK_RATE_11MB:
- return ZD_CS_CCK_RATE_11M;
- case IEEE80211_OFDM_RATE_6MB:
- return ZD_OFDM_RATE_6M;
- case IEEE80211_OFDM_RATE_9MB:
- return ZD_OFDM_RATE_9M;
- case IEEE80211_OFDM_RATE_12MB:
- return ZD_OFDM_RATE_12M;
- case IEEE80211_OFDM_RATE_18MB:
- return ZD_OFDM_RATE_18M;
- case IEEE80211_OFDM_RATE_24MB:
- return ZD_OFDM_RATE_24M;
- case IEEE80211_OFDM_RATE_36MB:
- return ZD_OFDM_RATE_36M;
- case IEEE80211_OFDM_RATE_48MB:
- return ZD_OFDM_RATE_48M;
- case IEEE80211_OFDM_RATE_54MB:
- return ZD_OFDM_RATE_54M;
- }
- return ZD_CS_CCK_RATE_1M;
+ return typed_rates[zd_rate & ZD_CS_RATE_MASK];
}
int zd_mac_set_mode(struct zd_mac *mac, u32 mode)
@@ -484,13 +635,13 @@ int zd_mac_get_range(struct zd_mac *mac, struct iw_range *range)
return 0;
}
-static int zd_calc_tx_length_us(u8 *service, u8 cs_rate, u16 tx_length)
+static int zd_calc_tx_length_us(u8 *service, u8 zd_rate, u16 tx_length)
{
static const u8 rate_divisor[] = {
- [ZD_CS_CCK_RATE_1M] = 1,
- [ZD_CS_CCK_RATE_2M] = 2,
- [ZD_CS_CCK_RATE_5_5M] = 11, /* bits must be doubled */
- [ZD_CS_CCK_RATE_11M] = 11,
+ [ZD_CCK_RATE_1M] = 1,
+ [ZD_CCK_RATE_2M] = 2,
+ [ZD_CCK_RATE_5_5M] = 11, /* bits must be doubled */
+ [ZD_CCK_RATE_11M] = 11,
[ZD_OFDM_RATE_6M] = 6,
[ZD_OFDM_RATE_9M] = 9,
[ZD_OFDM_RATE_12M] = 12,
@@ -504,15 +655,15 @@ static int zd_calc_tx_length_us(u8 *service, u8 cs_rate, u16 tx_length)
u32 bits = (u32)tx_length * 8;
u32 divisor;
- divisor = rate_divisor[cs_rate];
+ divisor = rate_divisor[zd_rate];
if (divisor == 0)
return -EINVAL;
- switch (cs_rate) {
- case ZD_CS_CCK_RATE_5_5M:
+ switch (zd_rate) {
+ case ZD_CCK_RATE_5_5M:
bits = (2*bits) + 10; /* round up to the next integer */
break;
- case ZD_CS_CCK_RATE_11M:
+ case ZD_CCK_RATE_11M:
if (service) {
u32 t = bits % 11;
*service &= ~ZD_PLCP_SERVICE_LENGTH_EXTENSION;
@@ -532,16 +683,16 @@ enum {
R2M_11A = 0x02,
};
-static u8 cs_rate_to_modulation(u8 cs_rate, int flags)
+static u8 zd_rate_to_modulation(u8 zd_rate, int flags)
{
u8 modulation;
- modulation = cs_typed_rate(cs_rate);
+ modulation = zd_rate_typed(zd_rate);
if (flags & R2M_SHORT_PREAMBLE) {
switch (ZD_CS_RATE(modulation)) {
- case ZD_CS_CCK_RATE_2M:
- case ZD_CS_CCK_RATE_5_5M:
- case ZD_CS_CCK_RATE_11M:
+ case ZD_CCK_RATE_2M:
+ case ZD_CCK_RATE_5_5M:
+ case ZD_CCK_RATE_11M:
modulation |= ZD_CS_CCK_PREA_SHORT;
return modulation;
}
@@ -558,39 +709,36 @@ static void cs_set_modulation(struct zd_mac *mac, struct zd_ctrlset *cs,
{
struct ieee80211softmac_device *softmac = ieee80211_priv(mac->netdev);
u16 ftype = WLAN_FC_GET_TYPE(le16_to_cpu(hdr->frame_ctl));
- u8 rate, cs_rate;
+ u8 rate, zd_rate;
int is_mgt = (ftype == IEEE80211_FTYPE_MGMT) != 0;
+ int is_multicast = is_multicast_ether_addr(hdr->addr1);
+ int short_preamble = ieee80211softmac_short_preamble_ok(softmac,
+ is_multicast, is_mgt);
+ int flags = 0;
+
+ /* FIXME: 802.11a? */
+ rate = ieee80211softmac_suggest_txrate(softmac, is_multicast, is_mgt);
- /* FIXME: 802.11a? short preamble? */
- rate = ieee80211softmac_suggest_txrate(softmac,
- is_multicast_ether_addr(hdr->addr1), is_mgt);
+ if (short_preamble)
+ flags |= R2M_SHORT_PREAMBLE;
- cs_rate = rate_to_cs_rate(rate);
- cs->modulation = cs_rate_to_modulation(cs_rate, 0);
+ zd_rate = rate_to_zd_rate(rate);
+ cs->modulation = zd_rate_to_modulation(zd_rate, flags);
}
static void cs_set_control(struct zd_mac *mac, struct zd_ctrlset *cs,
struct ieee80211_hdr_4addr *header)
{
+ struct ieee80211softmac_device *softmac = ieee80211_priv(mac->netdev);
unsigned int tx_length = le16_to_cpu(cs->tx_length);
u16 fctl = le16_to_cpu(header->frame_ctl);
u16 ftype = WLAN_FC_GET_TYPE(fctl);
u16 stype = WLAN_FC_GET_STYPE(fctl);
/*
- * CONTROL:
- * - start at 0x00
- * - if fragment 0, enable bit 0
+ * CONTROL TODO:
* - if backoff needed, enable bit 0
* - if burst (backoff not needed) disable bit 0
- * - if multicast, enable bit 1
- * - if PS-POLL frame, enable bit 2
- * - if in INDEPENDENT_BSS mode and zd1205_DestPowerSave, then enable
- * bit 4 (FIXME: wtf)
- * - if frag_len > RTS threshold, set bit 5 as long if it isnt
- * multicast or mgt
- * - if bit 5 is set, and we are in OFDM mode, unset bit 5 and set bit
- * 7
*/
cs->control = 0;
@@ -607,17 +755,18 @@ static void cs_set_control(struct zd_mac *mac, struct zd_ctrlset *cs,
if (stype == IEEE80211_STYPE_PSPOLL)
cs->control |= ZD_CS_PS_POLL_FRAME;
+ /* Unicast data frames over the threshold should have RTS */
if (!is_multicast_ether_addr(header->addr1) &&
- ftype != IEEE80211_FTYPE_MGMT &&
- tx_length > zd_netdev_ieee80211(mac->netdev)->rts)
- {
- /* FIXME: check the logic */
- if (ZD_CS_TYPE(cs->modulation) == ZD_CS_OFDM) {
- /* 802.11g */
- cs->control |= ZD_CS_SELF_CTS;
- } else { /* 802.11b */
- cs->control |= ZD_CS_RTS;
- }
+ ftype != IEEE80211_FTYPE_MGMT &&
+ tx_length > zd_netdev_ieee80211(mac->netdev)->rts)
+ cs->control |= ZD_CS_RTS;
+
+ /* Use CTS-to-self protection if required */
+ if (ZD_CS_TYPE(cs->modulation) == ZD_CS_OFDM &&
+ ieee80211softmac_protection_needed(softmac)) {
+ /* FIXME: avoid sending RTS *and* self-CTS, is that correct? */
+ cs->control &= ~ZD_CS_RTS;
+ cs->control |= ZD_CS_SELF_CTS;
}
/* FIXME: Management frame? */
@@ -721,7 +870,7 @@ struct zd_rt_hdr {
u8 rt_rate;
u16 rt_channel;
u16 rt_chbitmask;
-};
+} __attribute__((packed));
static void fill_rt_header(void *buffer, struct zd_mac *mac,
const struct ieee80211_rx_stats *stats,
@@ -782,9 +931,11 @@ static int is_data_packet_for_us(struct ieee80211_device *ieee,
(netdev->flags & IFF_PROMISC);
}
-/* Filters receiving packets. If it returns 1 send it to ieee80211_rx, if 0
- * return. If an error is detected -EINVAL is returned. ieee80211_rx_mgt() is
- * called here.
+/* Filters received packets. The function returns 1 if the packet should be
+ * forwarded to ieee80211_rx(). If the packet should be ignored the function
+ * returns 0. If an invalid packet is found the function returns -EINVAL.
+ *
+ * The function calls ieee80211_rx_mgt() directly.
*
* It has been based on ieee80211_rx_any.
*/
@@ -810,9 +961,9 @@ static int filter_rx(struct ieee80211_device *ieee,
ieee80211_rx_mgt(ieee, hdr, stats);
return 0;
case IEEE80211_FTYPE_CTL:
- /* Ignore invalid short buffers */
return 0;
case IEEE80211_FTYPE_DATA:
+ /* Ignore invalid short buffers */
if (length < sizeof(struct ieee80211_hdr_3addr))
return -EINVAL;
return is_data_packet_for_us(ieee, hdr);
@@ -993,6 +1144,7 @@ static void ieee_init(struct ieee80211_device *ieee)
static void softmac_init(struct ieee80211softmac_device *sm)
{
sm->set_channel = set_channel;
+ sm->bssinfo_change = bssinfo_change;
}
struct iw_statistics *zd_mac_get_wireless_stats(struct net_device *ndev)
@@ -1028,66 +1180,6 @@ struct iw_statistics *zd_mac_get_wireless_stats(struct net_device *ndev)
return iw_stats;
}
-#ifdef DEBUG
-static const char* decryption_types[] = {
- [ZD_RX_NO_WEP] = "none",
- [ZD_RX_WEP64] = "WEP64",
- [ZD_RX_TKIP] = "TKIP",
- [ZD_RX_AES] = "AES",
- [ZD_RX_WEP128] = "WEP128",
- [ZD_RX_WEP256] = "WEP256",
-};
-
-static const char *decryption_type_string(u8 type)
-{
- const char *s;
-
- if (type < ARRAY_SIZE(decryption_types)) {
- s = decryption_types[type];
- } else {
- s = NULL;
- }
- return s ? s : "unknown";
-}
-
-static int is_ofdm(u8 frame_status)
-{
- return (frame_status & ZD_RX_OFDM);
-}
-
-void zd_dump_rx_status(const struct rx_status *status)
-{
- const char* modulation;
- u8 quality;
-
- if (is_ofdm(status->frame_status)) {
- modulation = "ofdm";
- quality = status->signal_quality_ofdm;
- } else {
- modulation = "cck";
- quality = status->signal_quality_cck;
- }
- pr_debug("rx status %s strength %#04x qual %#04x decryption %s\n",
- modulation, status->signal_strength, quality,
- decryption_type_string(status->decryption_type));
- if (status->frame_status & ZD_RX_ERROR) {
- pr_debug("rx error %s%s%s%s%s%s\n",
- (status->frame_status & ZD_RX_TIMEOUT_ERROR) ?
- "timeout " : "",
- (status->frame_status & ZD_RX_FIFO_OVERRUN_ERROR) ?
- "fifo " : "",
- (status->frame_status & ZD_RX_DECRYPTION_ERROR) ?
- "decryption " : "",
- (status->frame_status & ZD_RX_CRC32_ERROR) ?
- "crc32 " : "",
- (status->frame_status & ZD_RX_NO_ADDR1_MATCH_ERROR) ?
- "addr1 " : "",
- (status->frame_status & ZD_RX_CRC16_ERROR) ?
- "crc16" : "");
- }
-}
-#endif /* DEBUG */
-
#define LINK_LED_WORK_DELAY HZ
static void link_led_handler(struct work_struct *work)