iwlwifi: mvm: allow to collect debug data from non-sleepable context

iwl_mvm_fw_dbg_collect allows to collect debug data from
the firmware. Most of the firmware interaction is done in
non-sleepable context. It makes little sense to force the
caller of iwl_mvm_fw_dbg_collect to sleep.
Defer the actual collection to a worker so that this
function will be able to be called from any context.

Reviewed-by: Eran Harary <eran.harary@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>

drivers/net/wireless/iwlwifi/mvm/fw.c

@@ -402,8 +402,6 @@ out:
 
 void iwl_mvm_fw_dbg_collect(struct iwl_mvm *mvm)
 {
-	lockdep_assert_held(&mvm->mutex);
-
 	/* stop recording */
 	if (mvm->cfg->device_family == IWL_DEVICE_FAMILY_7000) {
 		iwl_set_bits_prph(mvm->trans, MON_BUFF_SAMPLE_CTL, 0x100);
@@ -412,11 +410,7 @@ void iwl_mvm_fw_dbg_collect(struct iwl_mvm *mvm)
 		iwl_write_prph(mvm->trans, DBGC_OUT_CTRL, 0);
 	}
 
-	iwl_mvm_fw_error_dump(mvm);
-
-	/* start recording again */
-	WARN_ON_ONCE(mvm->fw->dbg_dest_tlv &&
-		     iwl_mvm_start_fw_dbg_conf(mvm, mvm->fw_dbg_conf));
+	schedule_work(&mvm->fw_error_dump_wk);
 }
 
 int iwl_mvm_start_fw_dbg_conf(struct iwl_mvm *mvm, enum iwl_fw_dbg_conf conf_id)

drivers/net/wireless/iwlwifi/mvm/ops.c

@@ -825,6 +825,12 @@ static void iwl_mvm_fw_error_dump_wk(struct work_struct *work)
 
 	mutex_lock(&mvm->mutex);
 	iwl_mvm_fw_error_dump(mvm);
+
+	/* start recording again if the firmware is not crashed */
+	WARN_ON_ONCE((!test_bit(STATUS_FW_ERROR, &mvm->trans->status)) &&
+		      mvm->fw->dbg_dest_tlv &&
+		      iwl_mvm_start_fw_dbg_conf(mvm, mvm->fw_dbg_conf));
+
 	mutex_unlock(&mvm->mutex);
 
 	iwl_mvm_unref(mvm, IWL_MVM_REF_FW_DBG_COLLECT);