wifi: nl80211: allow drivers to support subset of NL80211_CMD_SET_BSS

The so-called fullmac devices rely on firmware functionality and/or API to
change BSS parameters. Today there are limited drivers supporting the
nl80211 primitive, but they only handle a subset of the bss parameters
passed if any. The mac80211 driver does handle all parameters and stores
their configured values. Some of the BSS parameters were already conditional
by wiphy->features. For these the wiphy->bss_param_support and wiphy->features
fields are silently aligned in wiphy_register(). Maybe better to issue a warning
instead when they are misaligned.

Signed-off-by: Arend van Spriel <arend.vanspriel@broadcom.com>
Link: https://patch.msgid.link/20250817190435.1495094-2-arend.vanspriel@broadcom.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

2 files changed, 33 insertions, 0 deletions

diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index 7d881aa7e48b..4072a67c9cc9 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -2460,6 +2460,29 @@ struct mpath_info {
 };
 
 /**
+ * enum wiphy_bss_param_flags - bit positions for supported bss parameters.
+ *
+ * @WIPHY_BSS_PARAM_CTS_PROT: support changing CTS protection.
+ * @WIPHY_BSS_PARAM_SHORT_PREAMBLE: support changing short preamble usage.
+ * @WIPHY_BSS_PARAM_SHORT_SLOT_TIME: support changing short slot time usage.
+ * @WIPHY_BSS_PARAM_BASIC_RATES: support reconfiguring basic rates.
+ * @WIPHY_BSS_PARAM_AP_ISOLATE: support changing AP isolation.
+ * @WIPHY_BSS_PARAM_HT_OPMODE: support changing HT operating mode.
+ * @WIPHY_BSS_PARAM_P2P_CTWINDOW: support reconfiguring ctwindow.
+ * @WIPHY_BSS_PARAM_P2P_OPPPS: support changing P2P opportunistic power-save.
+ */
+enum wiphy_bss_param_flags {
+	WIPHY_BSS_PARAM_CTS_PROT = BIT(0),
+	WIPHY_BSS_PARAM_SHORT_PREAMBLE = BIT(1),
+	WIPHY_BSS_PARAM_SHORT_SLOT_TIME = BIT(2),
+	WIPHY_BSS_PARAM_BASIC_RATES = BIT(3),
+	WIPHY_BSS_PARAM_AP_ISOLATE = BIT(4),
+	WIPHY_BSS_PARAM_HT_OPMODE = BIT(5),
+	WIPHY_BSS_PARAM_P2P_CTWINDOW = BIT(6),
+	WIPHY_BSS_PARAM_P2P_OPPPS = BIT(7),
+};
+
+/**
  * struct bss_parameters - BSS parameters
  *
  * Used to change BSS parameters (mainly for AP mode).
@@ -5785,6 +5808,11 @@ struct wiphy_radio {
  *	and probe responses.  This value should be set if the driver
  *	wishes to limit the number of csa counters. Default (0) means
  *	infinite.
+ * @bss_param_support: bitmask indicating which bss_parameters as defined in
+ *	&struct bss_parameters the driver can actually handle in the
+ *	.change_bss() callback. The bit positions are defined in &enum
+ *	wiphy_bss_param_flags.
+ *
  * @bss_select_support: bitmask indicating the BSS selection criteria supported
  *	by the driver in the .connect() callback. The bit position maps to the
  *	attribute indices defined in &enum nl80211_bss_select_attr.
@@ -5970,6 +5998,7 @@ struct wiphy {
 
 	u8 max_num_csa_counters;
 
+	u32 bss_param_support;
 	u32 bss_select_support;
 
 	u8 nan_supported_bands;
diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h
index 4f08264bbc8e..6c07100fc01f 100644
--- a/include/uapi/linux/nl80211.h
+++ b/include/uapi/linux/nl80211.h
@@ -2930,6 +2930,9 @@ enum nl80211_commands {
  *	required alongside this attribute. Refer to
  *	@enum nl80211_s1g_short_beacon_attrs for the attribute definitions.
  *
+ * @NL80211_ATTR_BSS_PARAM: nested attribute used with %NL80211_CMD_GET_WIPHY
+ *	which indicates which BSS parameters can be modified.
+ *
  * @NUM_NL80211_ATTR: total number of nl80211_attrs available
  * @NL80211_ATTR_MAX: highest attribute number currently defined
  * @__NL80211_ATTR_AFTER_LAST: internal use
@@ -3491,6 +3494,7 @@ enum nl80211_attrs {
 
 	NL80211_ATTR_S1G_LONG_BEACON_PERIOD,
 	NL80211_ATTR_S1G_SHORT_BEACON,
+	NL80211_ATTR_BSS_PARAM,
 
 	/* add attributes here, update the policy in nl80211.c */