iwlwifi: mvm: don't keep an mvm ref when the interface is down

There is no reason to keep a reference when the interface is down,
since we are not really doing anything.  The reference is only needed
when the mac80211 start op (or a hw restart) is running, to prevent
going into runtime or system supend in the meantime.  This will allow
us to support runtime PM when the interface is down (in another
patch).

Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>

diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c b/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c
index a90f1ee..518a1d5 100644 (file)
--- a/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c
@@ -1004,10 +1004,18 @@ int __iwl_mvm_mac_start(struct iwl_mvm *mvm)
 
        lockdep_assert_held(&mvm->mutex);
 
-       /* Clean up some internal and mac80211 state on restart */
-       if (test_bit(IWL_MVM_STATUS_IN_HW_RESTART, &mvm->status))
+       if (test_bit(IWL_MVM_STATUS_IN_HW_RESTART, &mvm->status)) {
+               /* Clean up some internal and mac80211 state on restart */
                iwl_mvm_restart_cleanup(mvm);
-
+       } else {
+               /* Hold the reference to prevent runtime suspend while
+                * the start procedure runs.  It's a bit confusing
+                * that the UCODE_DOWN reference is taken, but it just
+                * means "UCODE is not UP yet". ( TODO: rename this
+                * reference).
+                */
+               iwl_mvm_ref(mvm, IWL_MVM_REF_UCODE_DOWN);
+       }
        ret = iwl_mvm_up(mvm);
 
        if (ret && test_bit(IWL_MVM_STATUS_IN_HW_RESTART, &mvm->status)) {
@@ -1110,14 +1118,6 @@ void __iwl_mvm_mac_stop(struct iwl_mvm *mvm)
         */
        memset(&mvm->accu_radio_stats, 0, sizeof(mvm->accu_radio_stats));
 
-       /*
-        * Disallow low power states when the FW is down by taking
-        * the UCODE_DOWN ref. in case of ongoing hw restart the
-        * ref is already taken, so don't take it again.
-        */
-       if (!test_bit(IWL_MVM_STATUS_IN_HW_RESTART, &mvm->status))
-               iwl_mvm_ref(mvm, IWL_MVM_REF_UCODE_DOWN);
-
        /* async_handlers_wk is now blocked */
 
        /*

diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/ops.c b/drivers/net/wireless/intel/iwlwifi/mvm/ops.c
index 3b0d597..b71c85b 100644 (file)
--- a/drivers/net/wireless/intel/iwlwifi/mvm/ops.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/ops.c
@@ -607,8 +607,8 @@ iwl_op_mode_mvm_start(struct iwl_trans *trans, const struct iwl_cfg *cfg,
 
        memset(&mvm->rx_stats, 0, sizeof(struct mvm_statistics_rx));
 
-       /* rpm starts with a taken ref. only set the appropriate bit here. */
-       mvm->refs[IWL_MVM_REF_UCODE_DOWN] = 1;
+       /* rpm starts with a taken reference, we can release it now */
+       iwl_trans_unref(mvm->trans);
 
        iwl_mvm_tof_init(mvm);