wifi: mac80211: fetch and store the EML capability information

We need to teach the low level driver about the EML capability which
includes information for EMLSR / EMLMR operation.

Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Gregory Greenman <gregory.greenman@intel.com>
Link: https://lore.kernel.org/r/20230504134511.828474-11-gregory.greenman@intel.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

diff --git a/include/linux/ieee80211.h b/include/linux/ieee80211.h
index c271184a396867d43100a98c81565ff48d6c3d45..fba4c44da832008bd5b9f9b6e5416e05e4fc0100 100644 (file)
--- a/include/linux/ieee80211.h
+++ b/include/linux/ieee80211.h
@@ -4635,6 +4635,41 @@ static inline u8 ieee80211_mle_common_size(const u8 *data)
        return sizeof(*mle) + common + mle->variable[0];
 }
 
+/**
+ * ieee80211_mle_get_eml_cap - returns the EML capability
+ * @data: pointer to the multi link EHT IE
+ *
+ * The element is assumed to be big enough. This must be checked by
+ * ieee80211_mle_size_ok().
+ * If the EML capability can't be found (the type is not basic, or
+ * the EML capability presence bit is clear), 0 will be returned.
+ */
+static inline u16 ieee80211_mle_get_eml_cap(const u8 *data)
+{
+       const struct ieee80211_multi_link_elem *mle = (const void *)data;
+       u16 control = le16_to_cpu(mle->control);
+       const u8 *common = mle->variable;
+
+       if (u16_get_bits(control, IEEE80211_ML_CONTROL_TYPE) !=
+           IEEE80211_ML_CONTROL_TYPE_BASIC)
+               return 0;
+
+       /* common points now at the beginning of ieee80211_mle_basic_common_info */
+       common += sizeof(struct ieee80211_mle_basic_common_info);
+
+       if (!(control & IEEE80211_MLC_BASIC_PRES_EML_CAPA))
+               return 0;
+
+       if (control & IEEE80211_MLC_BASIC_PRES_LINK_ID)
+               common += 1;
+       if (control & IEEE80211_MLC_BASIC_PRES_BSS_PARAM_CH_CNT)
+               common += 1;
+       if (control & IEEE80211_MLC_BASIC_PRES_MED_SYNC_DELAY)
+               common += 2;
+
+       return get_unaligned_le16(common);
+}
+
 /**
  * ieee80211_mle_size_ok - validate multi-link element size
  * @data: pointer to the element data

diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index ac0370e7687496074dcac37cd1149dbe15cd2dc3..f75d941eece80aa95c377eff81307b986a0c375e 100644 (file)
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -1790,6 +1790,7 @@ enum ieee80211_offload_flags {
  * @ps: power-save mode (STA only). This flag is NOT affected by
  *     offchannel/dynamic_ps operations.
  * @aid: association ID number, valid only when @assoc is true
+ * @eml_cap: EML capabilities as described in P802.11be_D2.2 Figure 9-1002k.
  * @arp_addr_list: List of IPv4 addresses for hardware ARP filtering. The
  *     may filter ARP queries targeted for other addresses than listed here.
  *     The driver must allow ARP queries targeted for all address listed here
@@ -1812,6 +1813,7 @@ struct ieee80211_vif_cfg {
        bool ibss_creator;
        bool ps;
        u16 aid;
+       u16 eml_cap;
 
        __be32 arp_addr_list[IEEE80211_BSS_ARP_ADDR_LIST_LEN];
        int arp_addr_cnt;

diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index 0020c9e41caa3a49b0f86d2e5921ac23d3b9b072..4ea383aafcac406674472774307a8adc071c585f 100644 (file)
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -4838,6 +4838,7 @@ static int ieee80211_prep_channel(struct ieee80211_sub_if_data *sdata,
                         IEEE80211_CONN_DISABLE_EHT)) &&
            he_oper) {
                const struct cfg80211_bss_ies *cbss_ies;
+               const struct element *eht_ml_elem;
                const u8 *eht_oper_ie;
 
                cbss_ies = rcu_dereference(cbss->ies);
@@ -4848,6 +4849,16 @@ static int ieee80211_prep_channel(struct ieee80211_sub_if_data *sdata,
                        eht_oper = (void *)(eht_oper_ie + 3);
                else
                        eht_oper = NULL;
+
+               eht_ml_elem = cfg80211_find_ext_elem(WLAN_EID_EXT_EHT_MULTI_LINK,
+                                                    cbss_ies->data, cbss_ies->len);
+
+               /* data + 1 / datalen - 1 since it's an extended element */
+               if (eht_ml_elem &&
+                   ieee80211_mle_size_ok(eht_ml_elem->data + 1,
+                                         eht_ml_elem->datalen - 1))
+                       sdata->vif.cfg.eml_cap =
+                               ieee80211_mle_get_eml_cap(eht_ml_elem->data + 1);
        }
 
        /* Allow VHT if at least one channel on the sband supports 80 MHz */