This patch adds support to set transmit power setting type and transmit
power level attributes to NL80211_CMD_SET_STATION in order to facilitate
adjusting the transmit power level of a station associated to the AP.
The added attributes allow selection of automatic and limited transmit
power level, with the level defined in mBm format.
Signed-off-by: Ashok Raj Nagarajan <[email protected]>
---
v2:
- refactor the shared code
- "keep what you had" using STATION_PARAM_APPLY_* BIT
- feature flag to let the user know if this feature is supported or not (Johannes)
v3:
- fix the limitation of changing the txpwr after association (Ben Greear)
include/net/cfg80211.h | 6 ++++++
include/uapi/linux/nl80211.h | 15 ++++++++++++++
net/wireless/nl80211.c | 48 ++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 69 insertions(+)
diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index 814be4b..661e0ea 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -808,6 +808,7 @@ enum station_parameters_apply_mask {
STATION_PARAM_APPLY_UAPSD = BIT(0),
STATION_PARAM_APPLY_CAPABILITY = BIT(1),
STATION_PARAM_APPLY_PLINK_STATE = BIT(2),
+ STATION_PARAM_APPLY_STA_TXPOWER = BIT(3),
};
/**
@@ -849,6 +850,10 @@ enum station_parameters_apply_mask {
* @opmode_notif: operating mode field from Operating Mode Notification
* @opmode_notif_used: information if operating mode field is used
* @support_p2p_ps: information if station supports P2P PS mechanism
+ * @txpwr: tx power (in mBm) to be used for sending data traffic. If tx power
+ * is not provided, the default per-interface tx power setting will be
+ * overriding. Driver should be picking up the lowest tx power, either tx
+ * power per-interface or per-station.
*/
struct station_parameters {
const u8 *supported_rates;
@@ -876,6 +881,7 @@ struct station_parameters {
u8 opmode_notif;
bool opmode_notif_used;
int support_p2p_ps;
+ u16 txpwr;
};
/**
diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h
index 6b76e3b..de2f72c 100644
--- a/include/uapi/linux/nl80211.h
+++ b/include/uapi/linux/nl80211.h
@@ -1980,6 +1980,15 @@ enum nl80211_commands {
* @NL80211_ATTR_BSSID: The BSSID of the AP. Note that %NL80211_ATTR_MAC is also
* used in various commands/events for specifying the BSSID.
*
+ * @NL80211_ATTR_STA_TX_POWER_SETTING: Transmit power setting type (u32) for
+ * station associated with the AP. See &enum nl80211_tx_power_setting for
+ * possible values.
+ * @NL80211_ATTR_STA_TX_POWER: Transmit power level (u32) in mBm units. This
+ * allows to set Tx power for a station. If this attribute is not included,
+ * the default per-interface tx power setting will be overriding. Driver
+ * should be picking up the lowest tx power, either tx power per-interface
+ * or per-station.
+ *
* @NUM_NL80211_ATTR: total number of nl80211_attrs available
* @NL80211_ATTR_MAX: highest attribute number currently defined
* @__NL80211_ATTR_AFTER_LAST: internal use
@@ -2386,6 +2395,9 @@ enum nl80211_attrs {
NL80211_ATTR_BSSID,
+ NL80211_ATTR_STA_TX_POWER_SETTING,
+ NL80211_ATTR_STA_TX_POWER,
+
/* add attributes here, update the policy in nl80211.c */
__NL80211_ATTR_AFTER_LAST,
@@ -4697,6 +4709,8 @@ enum nl80211_feature_flags {
* configuration (AP/mesh) with VHT rates.
* @NL80211_EXT_FEATURE_FILS_STA: This driver supports Fast Initial Link Setup
* with user space SME (NL80211_CMD_AUTHENTICATE) in station mode.
+ * @NL80211_EXT_FEATURE_STA_TX_PWR: This driver supports controlling tx power
+ * to a station.
*
* @NUM_NL80211_EXT_FEATURES: number of extended features.
* @MAX_NL80211_EXT_FEATURES: highest extended feature index.
@@ -4712,6 +4726,7 @@ enum nl80211_ext_feature_index {
NL80211_EXT_FEATURE_BEACON_RATE_HT,
NL80211_EXT_FEATURE_BEACON_RATE_VHT,
NL80211_EXT_FEATURE_FILS_STA,
+ NL80211_EXT_FEATURE_STA_TX_PWR,
/* add new features before the definition below */
NUM_NL80211_EXT_FEATURES,
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index ef5eff93..701c08a 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -246,6 +246,8 @@ enum nl80211_multicast_groups {
[NL80211_ATTR_STA_SUPPORTED_RATES] = { .type = NLA_BINARY,
.len = NL80211_MAX_SUPP_RATES },
[NL80211_ATTR_STA_PLINK_ACTION] = { .type = NLA_U8 },
+ [NL80211_ATTR_STA_TX_POWER_SETTING] = { .type = NLA_U32 },
+ [NL80211_ATTR_STA_TX_POWER] = { .type = NLA_U32 },
[NL80211_ATTR_STA_VLAN] = { .type = NLA_U32 },
[NL80211_ATTR_MNTR_FLAGS] = { /* NLA_NESTED can't be empty */ },
[NL80211_ATTR_MESH_ID] = { .type = NLA_BINARY,
@@ -4755,6 +4757,40 @@ static int nl80211_set_station_tdls(struct genl_info *info,
return nl80211_parse_sta_wme(info, params);
}
+static int nl80211_parse_sta_txpower_setting(struct genl_info *info,
+ struct station_parameters *params)
+{
+ struct cfg80211_registered_device *rdev = info->user_ptr[0];
+ enum nl80211_tx_power_setting type;
+ int idx;
+
+ if (!rdev->ops->set_tx_power ||
+ !wiphy_ext_feature_isset(&rdev->wiphy,
+ NL80211_EXT_FEATURE_STA_TX_PWR))
+ return -EOPNOTSUPP;
+
+ idx = NL80211_ATTR_STA_TX_POWER_SETTING;
+ type = nla_get_u32(info->attrs[idx]);
+
+ if (!info->attrs[NL80211_ATTR_STA_TX_POWER] &&
+ (type != NL80211_TX_POWER_AUTOMATIC))
+ return -EINVAL;
+
+ if (type != NL80211_TX_POWER_AUTOMATIC) {
+ if (type == NL80211_TX_POWER_LIMITED) {
+ idx = NL80211_ATTR_STA_TX_POWER;
+ params->txpwr = nla_get_u32(info->attrs[idx]);
+ } else {
+ return -EINVAL;
+ }
+ } else {
+ params->txpwr = 0;
+ }
+ params->sta_modify_mask |= STATION_PARAM_APPLY_STA_TXPOWER;
+
+ return 0;
+}
+
static int nl80211_set_station(struct sk_buff *skb, struct genl_info *info)
{
struct cfg80211_registered_device *rdev = info->user_ptr[0];
@@ -4854,6 +4890,12 @@ static int nl80211_set_station(struct sk_buff *skb, struct genl_info *info)
params.local_pm = pm;
}
+ if (info->attrs[NL80211_ATTR_STA_TX_POWER_SETTING]) {
+ err = nl80211_parse_sta_txpower_setting(info, ¶ms);
+ if (err)
+ return err;
+ }
+
/* Include parameters for TDLS peer (will check later) */
err = nl80211_set_station_tdls(info, ¶ms);
if (err)
@@ -4981,6 +5023,12 @@ static int nl80211_new_station(struct sk_buff *skb, struct genl_info *info)
return -EINVAL;
}
+ if (info->attrs[NL80211_ATTR_STA_TX_POWER_SETTING]) {
+ err = nl80211_parse_sta_txpower_setting(info, ¶ms);
+ if (err)
+ return err;
+ }
+
err = nl80211_parse_sta_channel_info(info, ¶ms);
if (err)
return err;
--
1.9.1
> + * @txpwr: tx power (in mBm) to be used for sending data traffic. If
> tx power
> + * is not provided, the default per-interface tx power
> setting will be
> + * overriding. Driver should be picking up the lowest tx
> power, either tx
> + * power per-interface or per-station.
> */
> struct station_parameters {
> const u8 *supported_rates;
> @@ -876,6 +881,7 @@ struct station_parameters {
> u8 opmode_notif;
> bool opmode_notif_used;
> int support_p2p_ps;
> + u16 txpwr;
> };
Wouldn't it be better to add the tx power type (limited/automatic) here
as well? That way, we don't have to play games with 0 meaning automatic
(which you didn't even document, but seems to be the case), when in
fact 0dBm could technically be a valid TX power as well.
> + idx = NL80211_ATTR_STA_TX_POWER_SETTING;
> + type = nla_get_u32(info->attrs[idx]);
> +
> + if (!info->attrs[NL80211_ATTR_STA_TX_POWER] &&
> + (type != NL80211_TX_POWER_AUTOMATIC))
> + return -EINVAL;
> +
> + if (type != NL80211_TX_POWER_AUTOMATIC) {
> + if (type == NL80211_TX_POWER_LIMITED) {
> + idx = NL80211_ATTR_STA_TX_POWER;
> + params->txpwr = nla_get_u32(info-
> >attrs[idx]);
> + } else {
> + return -EINVAL;
> + }
> + } else {
> + params->txpwr = 0;
> + }
This could be nicer using a switch on the type, perhaps?
> + if (info->attrs[NL80211_ATTR_STA_TX_POWER_SETTING]) {
> + err = nl80211_parse_sta_txpower_setting(info,
¶ms);
> + if (err)
> + return err;
> + }
Why not move the check that the attribute exists into the function?
johannes