mac80211: use ps-poll when dynamic power save mode is disabled

When a directed tim bit is set, mac80211 currently disables power save
ands sends a null frame to the AP. But if dynamic power save is
disabled, mac80211 will not enable power save ever gain. Fix this by
adding ps-poll functionality to mac80211. When a directed tim bit is
set, mac80211 sends a ps-poll frame to the AP and checks for the more
data bit in the returned data frames.

Using ps-poll is slower than waking up with null frame, but it's saves more
power in cases where the traffic is low. Userspace can control if either
ps-poll or null wakeup method is used by enabling and disabling dynamic
power save.

Signed-off-by: Kalle Valo <kalle.valo@nokia.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This commit is contained in:
Kalle Valo
2009-02-10 17:09:31 +02:00
committed by John W. Linville
parent 1fb3606bc5
commit 572e001221
3 changed files with 88 additions and 3 deletions

View File

@@ -511,6 +511,39 @@ static void ieee80211_send_deauth_disassoc(struct ieee80211_sub_if_data *sdata,
ieee80211_tx_skb(sdata, skb, ifsta->flags & IEEE80211_STA_MFP_ENABLED);
}
void ieee80211_send_pspoll(struct ieee80211_local *local,
struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_if_sta *ifsta = &sdata->u.sta;
struct ieee80211_pspoll *pspoll;
struct sk_buff *skb;
u16 fc;
skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*pspoll));
if (!skb) {
printk(KERN_DEBUG "%s: failed to allocate buffer for "
"pspoll frame\n", sdata->dev->name);
return;
}
skb_reserve(skb, local->hw.extra_tx_headroom);
pspoll = (struct ieee80211_pspoll *) skb_put(skb, sizeof(*pspoll));
memset(pspoll, 0, sizeof(*pspoll));
fc = IEEE80211_FTYPE_CTL | IEEE80211_STYPE_PSPOLL | IEEE80211_FCTL_PM;
pspoll->frame_control = cpu_to_le16(fc);
pspoll->aid = cpu_to_le16(ifsta->aid);
/* aid in PS-Poll has its two MSBs each set to 1 */
pspoll->aid |= cpu_to_le16(1 << 15 | 1 << 14);
memcpy(pspoll->bssid, ifsta->bssid, ETH_ALEN);
memcpy(pspoll->ta, sdata->dev->dev_addr, ETH_ALEN);
ieee80211_tx_skb(sdata, skb, 0);
return;
}
/* MLME */
static void ieee80211_sta_def_wmm_params(struct ieee80211_sub_if_data *sdata,
struct ieee80211_bss *bss)
@@ -1868,9 +1901,24 @@ static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata,
directed_tim = ieee80211_check_tim(&elems, ifsta->aid);
if (directed_tim) {
local->hw.conf.flags &= ~IEEE80211_CONF_PS;
ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_PS);
ieee80211_send_nullfunc(local, sdata, 0);
if (local->hw.conf.dynamic_ps_timeout > 0) {
local->hw.conf.flags &= ~IEEE80211_CONF_PS;
ieee80211_hw_config(local,
IEEE80211_CONF_CHANGE_PS);
ieee80211_send_nullfunc(local, sdata, 0);
} else {
local->pspolling = true;
/*
* Here is assumed that the driver will be
* able to send ps-poll frame and receive a
* response even though power save mode is
* enabled, but some drivers might require
* to disable power save here. This needs
* to be investigated.
*/
ieee80211_send_pspoll(local, sdata);
}
}
}