1 files changed, 35 insertions, 2 deletions

diff --git a/drivers/net/wireless/iwlwifi/mvm/mac-ctxt.c b/drivers/net/wireless/iwlwifi/mvm/mac-ctxt.c
index 0854dc338881..c33bec83b807 100644
--- a/drivers/net/wireless/iwlwifi/mvm/mac-ctxt.c
+++ b/drivers/net/wireless/iwlwifi/mvm/mac-ctxt.c
@@ -585,10 +585,43 @@ static void iwl_mvm_mac_ctxt_cmd_fill_sta(struct iwl_mvm *mvm,
                                           struct iwl_mac_data_sta *ctxt_sta)
 {
         /* We need the dtim_period to set the MAC as associated */
-        if (vif->bss_conf.assoc && vif->bss_conf.dtim_period)
+        if (vif->bss_conf.assoc && vif->bss_conf.dtim_period) {
+                u32 dtim_offs;
+
+                /*
+                 * The DTIM count counts down, so when it is N that means N
+                 * more beacon intervals happen until the DTIM TBTT. Therefore
+                 * add this to the current time. If that ends up being in the
+                 * future, the firmware will handle it.
+                 *
+                 * Also note that the system_timestamp (which we get here as
+                 * "sync_device_ts") and TSF timestamp aren't at exactly the
+                 * same offset in the frame -- the TSF is at the first symbol
+                 * of the TSF, the system timestamp is at signal acquisition
+                 * time. This means there's an offset between them of at most
+                 * a few hundred microseconds (24 * 8 bits + PLCP time gives
+                 * 384us in the longest case), this is currently not relevant
+                 * as the firmware wakes up around 2ms before the TBTT.
+                 */
+                dtim_offs = vif->bss_conf.sync_dtim_count *
+                                vif->bss_conf.beacon_int;
+                /* convert TU to usecs */
+                dtim_offs *= 1024;
+
+                ctxt_sta->dtim_tsf =
+                        cpu_to_le64(vif->bss_conf.sync_tsf + dtim_offs);
+                ctxt_sta->dtim_time =
+                        cpu_to_le32(vif->bss_conf.sync_device_ts + dtim_offs);
+
+                IWL_DEBUG_INFO(mvm, "DTIM TBTT is 0x%llx/0x%x, offset %d\n",
+                               le64_to_cpu(ctxt_sta->dtim_tsf),
+                               le32_to_cpu(ctxt_sta->dtim_time),
+                               dtim_offs);
+
                 ctxt_sta->is_assoc = cpu_to_le32(1);
-        else
+        } else {
                 ctxt_sta->is_assoc = cpu_to_le32(0);
+        }
 
         ctxt_sta->bi = cpu_to_le32(vif->bss_conf.beacon_int);
         ctxt_sta->bi_reciprocal =