2008-11-26 10:34:45

by Jouni Malinen

[permalink] [raw]
Subject: [PATCH] nl80211: Add frequency configuration (including HT40)

This patch adds new NL80211_CMD_SET_WIPHY attributes
NL80211_ATTR_WIPHY_FREQ and NL80211_ATTR_WIPHY_SEC_CHAN_OFFSET to allow
userspace to set the operating channel (e.g., hostapd for AP mode).

Signed-off-by: Jouni Malinen <[email protected]>


Index: wireless-testing/include/linux/nl80211.h
===================================================================
--- wireless-testing.orig/include/linux/nl80211.h 2008-11-26 09:28:51.000000000 +0200
+++ wireless-testing/include/linux/nl80211.h 2008-11-26 09:36:01.000000000 +0200
@@ -26,8 +26,9 @@
* @NL80211_CMD_GET_WIPHY: request information about a wiphy or dump request
* to get a list of all present wiphys.
* @NL80211_CMD_SET_WIPHY: set wiphy parameters, needs %NL80211_ATTR_WIPHY or
- * %NL80211_ATTR_IFINDEX; can be used to set %NL80211_ATTR_WIPHY_NAME
- * and/or %NL80211_ATTR_WIPHY_TXQ_PARAMS.
+ * %NL80211_ATTR_IFINDEX; can be used to set %NL80211_ATTR_WIPHY_NAME,
+ * %NL80211_ATTR_WIPHY_TXQ_PARAMS, %NL80211_ATTR_WIPHY_FREQ, and/or
+ * %NL80211_ATTR_WIPHY_SEC_CHAN_OFFSET.
* @NL80211_CMD_NEW_WIPHY: Newly created wiphy, response to get request
* or rename notification. Has attributes %NL80211_ATTR_WIPHY and
* %NL80211_ATTR_WIPHY_NAME.
@@ -180,6 +181,12 @@
* /sys/class/ieee80211/<phyname>/index
* @NL80211_ATTR_WIPHY_NAME: wiphy name (used for renaming)
* @NL80211_ATTR_WIPHY_TXQ_PARAMS: a nested array of TX queue parameters
+ * @NL80211_ATTR_WIPHY_FREQ: frequency of the selected channel in MHz
+ * @NL80211_ATTR_WIPHY_SEC_CHAN_OFFSET: included with NL80211_ATTR_WIPHY_FREQ
+ * if HT20 or HT40 are allowed (i.e., 802.11n disabled if not included):
+ * NL80211_SEC_CHAN_DISABLED = HT20 only
+ * NL80211_SEC_CHAN_BELOW = secondary channel is below the primary channel
+ * NL80211_SEC_CHAN_ABOVE = secondary channel is above the primary channel
*
* @NL80211_ATTR_IFINDEX: network interface index of the device to operate on
* @NL80211_ATTR_IFNAME: network interface name
@@ -315,6 +322,8 @@
NL80211_ATTR_BSS_BASIC_RATES,

NL80211_ATTR_WIPHY_TXQ_PARAMS,
+ NL80211_ATTR_WIPHY_FREQ,
+ NL80211_ATTR_WIPHY_SEC_CHAN_OFFSET,

/* add attributes here, update the policy in nl80211.c */

@@ -329,6 +338,8 @@
#define NL80211_ATTR_HT_CAPABILITY NL80211_ATTR_HT_CAPABILITY
#define NL80211_ATTR_BSS_BASIC_RATES NL80211_ATTR_BSS_BASIC_RATES
#define NL80211_ATTR_WIPHY_TXQ_PARAMS NL80211_ATTR_WIPHY_TXQ_PARAMS
+#define NL80211_ATTR_WIPHY_FREQ NL80211_ATTR_WIPHY_FREQ
+#define NL80211_ATTR_WIPHY_SEC_CHAN_OFFSET NL80211_ATTR_WIPHY_SEC_CHAN_OFFSET

#define NL80211_MAX_SUPP_RATES 32
#define NL80211_MAX_SUPP_REG_RULES 32
@@ -742,4 +753,10 @@
NL80211_TXQ_Q_BK
};

+enum nl80211_sec_chan_offset {
+ NL80211_SEC_CHAN_NO_HT /* No HT */,
+ NL80211_SEC_CHAN_DISABLED /* HT20 only */,
+ NL80211_SEC_CHAN_BELOW /* HT40- */,
+ NL80211_SEC_CHAN_ABOVE /* HT40+ */
+};
#endif /* __LINUX_NL80211_H */
Index: wireless-testing/include/net/cfg80211.h
===================================================================
--- wireless-testing.orig/include/net/cfg80211.h 2008-11-26 09:28:51.000000000 +0200
+++ wireless-testing/include/net/cfg80211.h 2008-11-26 09:38:12.000000000 +0200
@@ -450,6 +450,10 @@
* @change_bss: Modify parameters for a given BSS.
*
* @set_txq_params: Set TX queue parameters
+ *
+ * @set_channel: Set channel (freq = frequency in MHz, sec_chan_offset:
+ * 0 = HT40 disabled; 1 = HT40 enabled, secondary channel above primary;
+ * -1 = HT40 enabled, secondary channel below primary)
*/
struct cfg80211_ops {
int (*add_virtual_intf)(struct wiphy *wiphy, char *name,
@@ -513,6 +517,9 @@

int (*set_txq_params)(struct wiphy *wiphy,
struct ieee80211_txq_params *params);
+
+ int (*set_channel)(struct wiphy *wiphy, int freq, bool ht_enabled,
+ int sec_chan_offset);
};

#endif /* __NET_CFG80211_H */
Index: wireless-testing/net/mac80211/cfg.c
===================================================================
--- wireless-testing.orig/net/mac80211/cfg.c 2008-11-26 09:28:52.000000000 +0200
+++ wireless-testing/net/mac80211/cfg.c 2008-11-26 10:12:04.000000000 +0200
@@ -1095,6 +1095,23 @@
return 0;
}

+static int ieee80211_set_channel(struct wiphy *wiphy, int freq,
+ bool ht_enabled, int sec_chan_offset)
+{
+ struct ieee80211_local *local = wiphy_priv(wiphy);
+ struct ieee80211_channel *chan;
+
+ chan = ieee80211_get_channel(local->hw.wiphy, freq);
+ if (!chan)
+ return -EINVAL;
+
+ local->oper_channel = chan;
+ local->oper_ht_enabled = ht_enabled;
+ local->oper_sec_chan_offset = sec_chan_offset;
+
+ return ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
+}
+
struct cfg80211_ops mac80211_config_ops = {
.add_virtual_intf = ieee80211_add_iface,
.del_virtual_intf = ieee80211_del_iface,
@@ -1122,4 +1139,5 @@
#endif
.change_bss = ieee80211_change_bss,
.set_txq_params = ieee80211_set_txq_params,
+ .set_channel = ieee80211_set_channel,
};
Index: wireless-testing/net/wireless/nl80211.c
===================================================================
--- wireless-testing.orig/net/wireless/nl80211.c 2008-11-26 09:28:52.000000000 +0200
+++ wireless-testing/net/wireless/nl80211.c 2008-11-26 10:25:36.000000000 +0200
@@ -59,6 +59,8 @@
[NL80211_ATTR_WIPHY_NAME] = { .type = NLA_NUL_STRING,
.len = BUS_ID_SIZE-1 },
[NL80211_ATTR_WIPHY_TXQ_PARAMS] = { .type = NLA_NESTED },
+ [NL80211_ATTR_WIPHY_FREQ] = { .type = NLA_U32 },
+ [NL80211_ATTR_WIPHY_SEC_CHAN_OFFSET] = { .type = NLA_U8 },

[NL80211_ATTR_IFTYPE] = { .type = NLA_U32 },
[NL80211_ATTR_IFINDEX] = { .type = NLA_U32 },
@@ -359,6 +361,60 @@
}
}

+ if (info->attrs[NL80211_ATTR_WIPHY_FREQ]) {
+ int sec_chan_offset = 0;
+ bool ht_enabled = false;
+ struct ieee80211_channel *chan;
+ u32 freq;
+
+ if (!rdev->ops->set_channel) {
+ result = -EOPNOTSUPP;
+ goto bad_res;
+ }
+
+ if (info->attrs[NL80211_ATTR_WIPHY_SEC_CHAN_OFFSET]) {
+ u8 val = nla_get_u8(
+ info->attrs[
+ NL80211_ATTR_WIPHY_SEC_CHAN_OFFSET]);
+ switch (val) {
+ case NL80211_SEC_CHAN_BELOW:
+ ht_enabled = true;
+ sec_chan_offset = -1;
+ break;
+ case NL80211_SEC_CHAN_ABOVE:
+ ht_enabled = true;
+ sec_chan_offset = 1;
+ break;
+ case NL80211_SEC_CHAN_DISABLED:
+ ht_enabled = true;
+ break;
+ }
+ }
+
+ freq = nla_get_u32(info->attrs[NL80211_ATTR_WIPHY_FREQ]);
+ chan = ieee80211_get_channel(&rdev->wiphy, freq);
+ if (!chan || chan->flags & IEEE80211_CHAN_DISABLED) {
+ /* Primary channel not allowed */
+ result = -EINVAL;
+ goto bad_res;
+ }
+ if (sec_chan_offset) {
+ chan = ieee80211_get_channel(
+ &rdev->wiphy, freq + sec_chan_offset * 20);
+ if (!chan || chan->flags & IEEE80211_CHAN_DISABLED) {
+ /* Secondary channel not allowed */
+ result = -EINVAL;
+ goto bad_res;
+ }
+ }
+
+ result = rdev->ops->set_channel(&rdev->wiphy, freq, ht_enabled,
+ sec_chan_offset);
+ if (result)
+ goto bad_res;
+ }
+
+
bad_res:
cfg80211_put_dev(rdev);
return result;
Index: wireless-testing/include/net/mac80211.h
===================================================================
--- wireless-testing.orig/include/net/mac80211.h 2008-11-26 09:28:52.000000000 +0200
+++ wireless-testing/include/net/mac80211.h 2008-11-26 09:28:54.000000000 +0200
@@ -507,6 +507,9 @@

struct ieee80211_ht_conf {
bool enabled;
+ int sec_chan_offset; /* 0 = HT40 disabled; -1 = HT40 enabled, secondary
+ * channel below primary; 1 = HT40 enabled,
+ * secondary channel above primary */
};

/**
Index: wireless-testing/net/mac80211/util.c
===================================================================
--- wireless-testing.orig/net/mac80211/util.c 2008-11-26 10:00:57.000000000 +0200
+++ wireless-testing/net/mac80211/util.c 2008-11-26 10:09:01.000000000 +0200
@@ -641,6 +641,8 @@
chan->flags & IEEE80211_CHAN_NO_IBSS)
return ret;
local->oper_channel = chan;
+ local->oper_ht_enabled = false;
+ local->oper_sec_chan_offset = 0;

if (local->sw_scanning || local->hw_scanning)
ret = 0;
Index: wireless-testing/net/mac80211/ieee80211_i.h
===================================================================
--- wireless-testing.orig/net/mac80211/ieee80211_i.h 2008-11-26 10:12:16.000000000 +0200
+++ wireless-testing/net/mac80211/ieee80211_i.h 2008-11-26 10:12:34.000000000 +0200
@@ -626,6 +626,8 @@
struct delayed_work scan_work;
struct ieee80211_sub_if_data *scan_sdata;
struct ieee80211_channel *oper_channel, *scan_channel;
+ bool oper_ht_enabled;
+ int oper_sec_chan_offset;
u8 scan_ssid[IEEE80211_MAX_SSID_LEN];
size_t scan_ssid_len;
struct list_head bss_list;
Index: wireless-testing/net/mac80211/main.c
===================================================================
--- wireless-testing.orig/net/mac80211/main.c 2008-11-26 10:09:09.000000000 +0200
+++ wireless-testing/net/mac80211/main.c 2008-11-26 10:11:49.000000000 +0200
@@ -195,20 +195,30 @@
struct ieee80211_channel *chan;
int ret = 0;
int power;
+ bool ht_enabled;
+ int sec_chan_offset;

might_sleep();

- if (local->sw_scanning)
+ if (local->sw_scanning) {
chan = local->scan_channel;
- else
+ ht_enabled = false;
+ sec_chan_offset = 0;
+ } else {
chan = local->oper_channel;
+ ht_enabled = local->oper_ht_enabled;
+ sec_chan_offset = local->oper_sec_chan_offset;
+ }

- if (chan != local->hw.conf.channel) {
+ if (chan != local->hw.conf.channel ||
+ ht_enabled != local->hw.conf.ht.enabled ||
+ sec_chan_offset != local->hw.conf.ht.sec_chan_offset) {
local->hw.conf.channel = chan;
+ local->hw.conf.ht.enabled = ht_enabled;
+ local->hw.conf.ht.sec_chan_offset = sec_chan_offset;
changed |= IEEE80211_CONF_CHANGE_CHANNEL;
}

-
if (!local->hw.conf.power_level)
power = chan->max_power;
else

--
Jouni Malinen PGP id EFC895FA