From: Felix Fietkau <nbd@nbd.name>
Date: Wed, 7 Aug 2024 13:31:07 +0200
Subject: [PATCH] wifi: cfg80211: report per wiphy radio antenna mask

With multi-radio devices, each radio typically gets a fixed set of antennas.
In order to be able to disable specific antennas for some radios, user space
needs to know which antenna mask bits are assigned to which radio.

Signed-off-by: Felix Fietkau <nbd@nbd.name>
---

--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -5443,6 +5443,8 @@ struct wiphy_radio_freq_range {
  * @iface_combinations: Valid interface combinations array, should not
  *	list single interface types.
  * @n_iface_combinations: number of entries in @iface_combinations array.
+ *
+ * @antenna_mask: bitmask of antennas connected to this radio.
  */
 struct wiphy_radio {
 	const struct wiphy_radio_freq_range *freq_range;
@@ -5450,6 +5452,8 @@ struct wiphy_radio {
 
 	const struct ieee80211_iface_combination *iface_combinations;
 	int n_iface_combinations;
+
+	u32 antenna_mask;
 };
 
 #define CFG80211_HW_TIMESTAMP_ALL_PEERS	0xffff
--- a/include/uapi/linux/nl80211.h
+++ b/include/uapi/linux/nl80211.h
@@ -8038,6 +8038,8 @@ enum nl80211_ap_settings_flags {
  * @NL80211_WIPHY_RADIO_ATTR_INTERFACE_COMBINATION: Supported interface
  *	combination for this radio. Attribute may be present multiple times
  *	and contains attributes defined in &enum nl80211_if_combination_attrs.
+ * @NL80211_WIPHY_RADIO_ATTR_ANTENNA_MASK: bitmask (u32) of antennas
+ *	connected to this radio.
  *
  * @__NL80211_WIPHY_RADIO_ATTR_LAST: Internal
  * @NL80211_WIPHY_RADIO_ATTR_MAX: Highest attribute
@@ -8048,6 +8050,7 @@ enum nl80211_wiphy_radio_attrs {
 	NL80211_WIPHY_RADIO_ATTR_INDEX,
 	NL80211_WIPHY_RADIO_ATTR_FREQ_RANGE,
 	NL80211_WIPHY_RADIO_ATTR_INTERFACE_COMBINATION,
+	NL80211_WIPHY_RADIO_ATTR_ANTENNA_MASK,
 
 	/* keep last */
 	__NL80211_WIPHY_RADIO_ATTR_LAST,
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -2431,6 +2431,11 @@ static int nl80211_put_radio(struct wiph
 	if (nla_put_u32(msg, NL80211_WIPHY_RADIO_ATTR_INDEX, idx))
 		goto nla_put_failure;
 
+	if (r->antenna_mask &&
+	    nla_put_u32(msg, NL80211_WIPHY_RADIO_ATTR_ANTENNA_MASK,
+			r->antenna_mask))
+		goto nla_put_failure;
+
 	for (i = 0; i < r->n_freq_range; i++) {
 		const struct wiphy_radio_freq_range *range = &r->freq_range[i];
 
