iwlwifi: mvm: add LQM vendor command and notification

LQM stands for Link Quality Measurement. The firmware
will collect a defined set of statitics (see the
notification for details) that allow to know how busy
the medium is. The driver issues a request to the firmware
that includes the duration of the measurement (the firmware
needs to be on channel for that amount of time) and the
timeout (in case the firmware has a lot of offchannel
activities). If the timeout elapses, the firmware will
send partial results which are still valuable.
In case of disassociation / channel switch and alike, the
driver is in charge of stopping the measurements and the
firmware will reply with partial results.

The user space API for now is debugfs only and will be
implmemented in an upcoming patch.

Signed-off-by: Aviya Erenfeld <aviya.erenfeld@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>

1 files changed, 71 insertions, 0 deletions

diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/utils.c b/drivers/net/wireless/intel/iwlwifi/mvm/utils.c
index 53cdc5760f68..2440248c8e69 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/utils.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/utils.c
@@ -1079,3 +1079,74 @@ void iwl_mvm_connection_loss(struct iwl_mvm *mvm, struct ieee80211_vif *vif,
 out:
         ieee80211_connection_loss(vif);
 }
+
+int iwl_mvm_send_lqm_cmd(struct ieee80211_vif *vif,
+                         enum iwl_lqm_cmd_operatrions operation,
+                         u32 duration, u32 timeout)
+{
+        struct iwl_mvm_vif *mvm_vif = iwl_mvm_vif_from_mac80211(vif);
+        struct iwl_link_qual_msrmnt_cmd cmd = {
+                .cmd_operation = cpu_to_le32(operation),
+                .mac_id = cpu_to_le32(mvm_vif->id),
+                .measurement_time = cpu_to_le32(duration),
+                .timeout = cpu_to_le32(timeout),
+        };
+        u32 cmdid =
+                iwl_cmd_id(LINK_QUALITY_MEASUREMENT_CMD, MAC_CONF_GROUP, 0);
+        int ret;
+
+        if (!fw_has_capa(&mvm_vif->mvm->fw->ucode_capa,
+                         IWL_UCODE_TLV_CAPA_LQM_SUPPORT))
+                return -EOPNOTSUPP;
+
+        if (vif->type != NL80211_IFTYPE_STATION || vif->p2p)
+                return -EINVAL;
+
+        switch (operation) {
+        case LQM_CMD_OPERATION_START_MEASUREMENT:
+                if (iwl_mvm_lqm_active(mvm_vif->mvm))
+                        return -EBUSY;
+                if (!vif->bss_conf.assoc)
+                        return -EINVAL;
+                mvm_vif->lqm_active = true;
+                break;
+        case LQM_CMD_OPERATION_STOP_MEASUREMENT:
+                if (!iwl_mvm_lqm_active(mvm_vif->mvm))
+                        return -EINVAL;
+                break;
+        default:
+                return -EINVAL;
+        }
+
+        ret = iwl_mvm_send_cmd_pdu(mvm_vif->mvm, cmdid, 0, sizeof(cmd),
+                                   &cmd);
+
+        /* command failed - roll back lqm_active state */
+        if (ret) {
+                mvm_vif->lqm_active =
+                        operation == LQM_CMD_OPERATION_STOP_MEASUREMENT;
+        }
+
+        return ret;
+}
+
+static void iwl_mvm_lqm_active_iterator(void *_data, u8 *mac,
+                                        struct ieee80211_vif *vif)
+{
+        struct iwl_mvm_vif *mvm_vif = iwl_mvm_vif_from_mac80211(vif);
+        bool *lqm_active = _data;
+
+        *lqm_active = *lqm_active || mvm_vif->lqm_active;
+}
+
+bool iwl_mvm_lqm_active(struct iwl_mvm *mvm)
+{
+        bool ret = false;
+
+        lockdep_assert_held(&mvm->mutex);
+        ieee80211_iterate_active_interfaces_atomic(
+                mvm->hw, IEEE80211_IFACE_ITER_NORMAL,
+                iwl_mvm_lqm_active_iterator, &ret);
+
+        return ret;
+}