zd_mac.c

linux内核源码

}

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(struct work_struct *work)
{
	struct zd_mac *mac =
		container_of(work, struct zd_mac, set_rts_cts_work.work);
	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(struct work_struct *work)
{
	struct zd_mac *mac =
		container_of(work, struct zd_mac, set_basic_rates_work.work);
	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 hi_rate = ieee80211softmac_highest_supported_rate(softmac,
			&bssinfo->supported_rates, 1);
		hi_rate = rate_to_zd_rate(hi_rate);

		spin_lock_irqsave(&mac->lock, flags);
		if (hi_rate != mac->rts_rate) {
			mac->rts_rate = hi_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_delayed_work(zd_workqueue, &mac->set_rts_cts_work, 0);
	}
	if (need_set_rates && !mac->updating_basic_rates) {
		mac->updating_basic_rates = 1;
		netif_stop_queue(mac->netdev);
		queue_delayed_work(zd_workqueue, &mac->set_basic_rates_work,
				   0);
	}
	spin_unlock_irqrestore(&mac->lock, flags);
}

static void set_channel(struct net_device *netdev, u8 channel)
{
	struct zd_mac *mac = zd_netdev_mac(netdev);

	dev_dbg_f(zd_mac_dev(mac), "channel %d\n", channel);

	zd_chip_set_channel(&mac->chip, channel);
}

int zd_mac_request_channel(struct zd_mac *mac, u8 channel)
{
	unsigned long lock_flags;
	struct ieee80211_device *ieee = zd_mac_to_ieee80211(mac);

	if (ieee->iw_mode == IW_MODE_INFRA)
		return -EPERM;

	spin_lock_irqsave(&mac->lock, lock_flags);
	if (!zd_regdomain_supports_channel(mac->regdomain, channel)) {
		spin_unlock_irqrestore(&mac->lock, lock_flags);
		return -EINVAL;
	}
	mac->requested_channel = channel;
	spin_unlock_irqrestore(&mac->lock, lock_flags);
	if (netif_running(mac->netdev))
		return zd_chip_set_channel(&mac->chip, channel);
	else
		return 0;
}

u8 zd_mac_get_channel(struct zd_mac *mac)
{
	u8 channel = zd_chip_get_channel(&mac->chip);

	dev_dbg_f(zd_mac_dev(mac), "channel %u\n", channel);
	return channel;
}

int zd_mac_set_mode(struct zd_mac *mac, u32 mode)
{
	struct ieee80211_device *ieee;

	switch (mode) {
	case IW_MODE_AUTO:
	case IW_MODE_ADHOC:
	case IW_MODE_INFRA:
		mac->netdev->type = ARPHRD_ETHER;
		break;
	case IW_MODE_MONITOR:
		mac->netdev->type = ARPHRD_IEEE80211_RADIOTAP;
		break;
	default:
		dev_dbg_f(zd_mac_dev(mac), "wrong mode %u\n", mode);
		return -EINVAL;
	}

	ieee = zd_mac_to_ieee80211(mac);
	ZD_ASSERT(!irqs_disabled());
	spin_lock_irq(&ieee->lock);
	ieee->iw_mode = mode;
	spin_unlock_irq(&ieee->lock);

	if (netif_running(mac->netdev)) {
		int r = set_rx_filter(mac);
		if (r)
			return r;
		return set_sniffer(mac);
	}

	return 0;
}

int zd_mac_get_mode(struct zd_mac *mac, u32 *mode)
{
	unsigned long flags;
	struct ieee80211_device *ieee;

	ieee = zd_mac_to_ieee80211(mac);
	spin_lock_irqsave(&ieee->lock, flags);
	*mode = ieee->iw_mode;
	spin_unlock_irqrestore(&ieee->lock, flags);
	return 0;
}

int zd_mac_get_range(struct zd_mac *mac, struct iw_range *range)
{
	int i;
	const struct channel_range *channel_range;
	u8 regdomain;

	memset(range, 0, sizeof(*range));

	/* FIXME: Not so important and depends on the mode. For 802.11g
	 * usually this value is used. It seems to be that Bit/s number is
	 * given here.
	 */
	range->throughput = 27 * 1000 * 1000;

	range->max_qual.qual = 100;
	range->max_qual.level = 100;

	/* FIXME: Needs still to be tuned. */
	range->avg_qual.qual = 71;
	range->avg_qual.level = 80;

	/* FIXME: depends on standard? */
	range->min_rts = 256;
	range->max_rts = 2346;

	range->min_frag = MIN_FRAG_THRESHOLD;
	range->max_frag = MAX_FRAG_THRESHOLD;

	range->max_encoding_tokens = WEP_KEYS;
	range->num_encoding_sizes = 2;
	range->encoding_size[0] = 5;
	range->encoding_size[1] = WEP_KEY_LEN;

	range->we_version_compiled = WIRELESS_EXT;
	range->we_version_source = 20;

	range->enc_capa = IW_ENC_CAPA_WPA |  IW_ENC_CAPA_WPA2 |
			  IW_ENC_CAPA_CIPHER_TKIP | IW_ENC_CAPA_CIPHER_CCMP;

	ZD_ASSERT(!irqs_disabled());
	spin_lock_irq(&mac->lock);
	regdomain = mac->regdomain;
	spin_unlock_irq(&mac->lock);
	channel_range = zd_channel_range(regdomain);

	range->num_channels = channel_range->end - channel_range->start;
	range->old_num_channels = range->num_channels;
	range->num_frequency = range->num_channels;
	range->old_num_frequency = range->num_frequency;

	for (i = 0; i < range->num_frequency; i++) {
		struct iw_freq *freq = &range->freq[i];
		freq->i = channel_range->start + i;
		zd_channel_to_freq(freq, freq->i);
	}

	return 0;
}

static int zd_calc_tx_length_us(u8 *service, u8 zd_rate, u16 tx_length)
{
	/* ZD_PURE_RATE() must be used to remove the modulation type flag of
	 * the zd-rate values. */
	static const u8 rate_divisor[] = {
		[ZD_PURE_RATE(ZD_CCK_RATE_1M)]		=  1,
		[ZD_PURE_RATE(ZD_CCK_RATE_2M)]		=  2,

		/* bits must be doubled */
		[ZD_PURE_RATE(ZD_CCK_RATE_5_5M)]	= 11,

		[ZD_PURE_RATE(ZD_CCK_RATE_11M)]		= 11,
		[ZD_PURE_RATE(ZD_OFDM_RATE_6M)]		=  6,
		[ZD_PURE_RATE(ZD_OFDM_RATE_9M)]		=  9,
		[ZD_PURE_RATE(ZD_OFDM_RATE_12M)]	= 12,
		[ZD_PURE_RATE(ZD_OFDM_RATE_18M)]	= 18,
		[ZD_PURE_RATE(ZD_OFDM_RATE_24M)]	= 24,
		[ZD_PURE_RATE(ZD_OFDM_RATE_36M)]	= 36,
		[ZD_PURE_RATE(ZD_OFDM_RATE_48M)]	= 48,
		[ZD_PURE_RATE(ZD_OFDM_RATE_54M)]	= 54,
	};

	u32 bits = (u32)tx_length * 8;
	u32 divisor;

	divisor = rate_divisor[ZD_PURE_RATE(zd_rate)];
	if (divisor == 0)
		return -EINVAL;

	switch (zd_rate) {
	case ZD_CCK_RATE_5_5M:
		bits = (2*bits) + 10; /* round up to the next integer */
		break;
	case ZD_CCK_RATE_11M:
		if (service) {
			u32 t = bits % 11;
			*service &= ~ZD_PLCP_SERVICE_LENGTH_EXTENSION;
			if (0 < t && t <= 3) {
				*service |= ZD_PLCP_SERVICE_LENGTH_EXTENSION;
			}
		}
		bits += 10; /* round up to the next integer */
		break;
	}

	return bits/divisor;
}

static void cs_set_modulation(struct zd_mac *mac, struct zd_ctrlset *cs,
	                      struct ieee80211_hdr_4addr *hdr)
{
	struct ieee80211softmac_device *softmac = ieee80211_priv(mac->netdev);
	u16 ftype = WLAN_FC_GET_TYPE(le16_to_cpu(hdr->frame_ctl));
	u8 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);

	rate = ieee80211softmac_suggest_txrate(softmac, is_multicast, is_mgt);
	cs->modulation = rate_to_zd_rate(rate);

	/* Set short preamble bit when appropriate */
	if (short_preamble && ZD_MODULATION_TYPE(cs->modulation) == ZD_CCK
	    && cs->modulation != ZD_CCK_RATE_1M)
		cs->modulation |= ZD_CCK_PREA_SHORT;
}

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 TODO:
	 * - if backoff needed, enable bit 0
	 * - if burst (backoff not needed) disable bit 0
	 */

	cs->control = 0;

	/* First fragment */
	if (WLAN_GET_SEQ_FRAG(le16_to_cpu(header->seq_ctl)) == 0)
		cs->control |= ZD_CS_NEED_RANDOM_BACKOFF;

	/* Multicast */
	if (is_multicast_ether_addr(header->addr1))
		cs->control |= ZD_CS_MULTICAST;

	/* PS-POLL */
	if (ftype == IEEE80211_FTYPE_CTL && 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)
		cs->control |= ZD_CS_RTS;

	/* Use CTS-to-self protection if required */
	if (ZD_MODULATION_TYPE(cs->modulation) == ZD_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? */
}

static int fill_ctrlset(struct zd_mac *mac,
	                struct ieee80211_txb *txb,
			int frag_num)
{
	int r;
	struct sk_buff *skb = txb->fragments[frag_num];
	struct ieee80211_hdr_4addr *hdr =
		(struct ieee80211_hdr_4addr *) skb->data;
	unsigned int frag_len = skb->len + IEEE80211_FCS_LEN;
	unsigned int next_frag_len;
	unsigned int packet_length;
	struct zd_ctrlset *cs = (struct zd_ctrlset *)
		skb_push(skb, sizeof(struct zd_ctrlset));

	if (frag_num+1  < txb->nr_frags) {
		next_frag_len = txb->fragments[frag_num+1]->len +
			        IEEE80211_FCS_LEN;
	} else {
		next_frag_len = 0;
	}
	ZD_ASSERT(frag_len <= 0xffff);
	ZD_ASSERT(next_frag_len <= 0xffff);

	cs_set_modulation(mac, cs, hdr);

	cs->tx_length = cpu_to_le16(frag_len);

	cs_set_control(mac, cs, hdr);

	packet_length = frag_len + sizeof(struct zd_ctrlset) + 10;
	ZD_ASSERT(packet_length <= 0xffff);
	/* ZD1211B: Computing the length difference this way, gives us
	 * flexibility to compute the packet length.
	 */
	cs->packet_length = cpu_to_le16(zd_chip_is_zd1211b(&mac->chip) ?
			packet_length - frag_len : packet_length);

	/*
	 * CURRENT LENGTH:
	 * - transmit frame length in microseconds
	 * - seems to be derived from frame length
	 * - see Cal_Us_Service() in zdinlinef.h
	 * - if macp->bTxBurstEnable is enabled, then multiply by 4
	 *  - bTxBurstEnable is never set in the vendor driver
	 *
	 * SERVICE:
	 * - "for PLCP configuration"
	 * - always 0 except in some situations at 802.11b 11M
	 * - see line 53 of zdinlinef.h
	 */
	cs->service = 0;
	r = zd_calc_tx_length_us(&cs->service, ZD_RATE(cs->modulation),
		                 le16_to_cpu(cs->tx_length));
	if (r < 0)
		return r;
	cs->current_length = cpu_to_le16(r);

	if (next_frag_len == 0) {
		cs->next_frame_length = 0;
	} else {
		r = zd_calc_tx_length_us(NULL, ZD_RATE(cs->modulation),
			                 next_frag_len);
		if (r < 0)
			return r;
		cs->next_frame_length = cpu_to_le16(r);
	}