diff --git a/neutron_fwaas/extensions/firewall.py b/neutron_fwaas/extensions/firewall.py
index f1c5a0cec..013a24eff 100644
--- a/neutron_fwaas/extensions/firewall.py
+++ b/neutron_fwaas/extensions/firewall.py
@@ -102,6 +102,7 @@ def convert_to_string(value):
         return str(value)
     return None
 
+
 firewall.RESOURCE_ATTRIBUTE_MAP[api_const.FIREWALL_RULES][
     'source_port']['convert_to'] = convert_to_string
 firewall.RESOURCE_ATTRIBUTE_MAP[api_const.FIREWALL_RULES][
diff --git a/neutron_fwaas/extensions/firewall_v2.py b/neutron_fwaas/extensions/firewall_v2.py
index 25aff1578..372b9d716 100644
--- a/neutron_fwaas/extensions/firewall_v2.py
+++ b/neutron_fwaas/extensions/firewall_v2.py
@@ -93,6 +93,7 @@ def convert_to_string(value):
         return str(value)
     return None
 
+
 firewall_v2.RESOURCE_ATTRIBUTE_MAP[api_const.FIREWALL_RULES][
     'source_port']['convert_to'] = convert_to_string
 firewall_v2.RESOURCE_ATTRIBUTE_MAP[api_const.FIREWALL_RULES][
diff --git a/neutron_fwaas/services/firewall/service_drivers/agents/drivers/linux/iptables_fwaas_v2.py b/neutron_fwaas/services/firewall/service_drivers/agents/drivers/linux/iptables_fwaas_v2.py
index e51641e9b..60efcb7fe 100644
--- a/neutron_fwaas/services/firewall/service_drivers/agents/drivers/linux/iptables_fwaas_v2.py
+++ b/neutron_fwaas/services/firewall/service_drivers/agents/drivers/linux/iptables_fwaas_v2.py
@@ -473,7 +473,7 @@ class IptablesFwaasDriver(fwaas_base_v2.FwaasDriverBase):
         # or destination port number is specified
         if (rule.get('source_port') is not None or
             rule.get('destination_port') is not None):
-                args += self._match_arg(rule.get('protocol'))
+            args += self._match_arg(rule.get('protocol'))
 
         args += self._port_arg('sport',
                                rule.get('protocol'),
diff --git a/neutron_fwaas/services/firewall/service_drivers/agents/l3reference/firewall_l3_agent_v2.py b/neutron_fwaas/services/firewall/service_drivers/agents/l3reference/firewall_l3_agent_v2.py
index ee2d3c3fa..fa5cbb95c 100644
--- a/neutron_fwaas/services/firewall/service_drivers/agents/l3reference/firewall_l3_agent_v2.py
+++ b/neutron_fwaas/services/firewall/service_drivers/agents/l3reference/firewall_l3_agent_v2.py
@@ -297,8 +297,8 @@ class FWaaSL3AgentExtension(l3_extension.L3AgentExtension):
             self.services_sync_needed = True
 
     def update_router(self, context, updated_router):
-        """Handles agent restart and router update. Fetches firewall groups from
-        plugin and updates driver.
+        """Handles agent restart and router update. Fetches firewall groups
+        from plugin and updates driver.
         """
         if not self.fwaas_enabled:
             return
diff --git a/neutron_fwaas/tests/functional/services/logapi/agents/drivers/iptables/test_log.py b/neutron_fwaas/tests/functional/services/logapi/agents/drivers/iptables/test_log.py
index d148ae185..e7409a7ff 100644
--- a/neutron_fwaas/tests/functional/services/logapi/agents/drivers/iptables/test_log.py
+++ b/neutron_fwaas/tests/functional/services/logapi/agents/drivers/iptables/test_log.py
@@ -239,8 +239,8 @@ class FWLoggingTestBase(framework.L3AgentTestFramework):
             with mock.patch.object(self.resource_rpc,
                                    'get_sg_log_info_for_port',
                                    return_value=log_info):
-                    self.log_driver.start_logging(self.context,
-                                                  router_info=router_info)
+                self.log_driver.start_logging(self.context,
+                                              router_info=router_info)
         elif log_resources:
             with mock.patch.object(self.resource_rpc,
                                    'get_sg_log_info_for_log_resources',
diff --git a/test-requirements.txt b/test-requirements.txt
index 926bcb3c2..e0f78bf03 100644
--- a/test-requirements.txt
+++ b/test-requirements.txt
@@ -1,7 +1,7 @@
 # The order of packages is significant, because pip processes them in the order
 # of appearance. Changing the order has an impact on the overall integration
 # process, which may cause wedges in the gate later.
-hacking!=0.13.0,<0.14,>=0.12.0 # Apache-2.0
+hacking>=1.1.0,<1.2.0 # Apache-2.0
 
 coverage!=4.4,>=4.0 # Apache-2.0
 flake8-import-order==0.12 # LGPLv3
diff --git a/tox.ini b/tox.ini
index 0b0d47598..4f7492dbc 100644
--- a/tox.ini
+++ b/tox.ini
@@ -154,7 +154,10 @@ ignore-path = .venv,.git,.tox,.tmp,*neutron_fwaas/locale*,*lib/python*,neutron_f
 # H205: Use assert(Greater|Less)(Equal) for comparison
 # H904: Delay string interpolations at logging calls
 # N521: jsonutils.loads must be used instead of json.loads
-ignore = E125,E126,E128,E129,E265,H404,H405,N530,N521
+# W504 line break after binary operator
+# (W503 and W504 are incompatible and we need to choose one of them.
+#  Existing codes follows W503, so we disable W504.)
+ignore = E125,E126,E128,E129,E265,H404,H405,N530,N521,W504
 enable-extensions=H106,H203,H204,H205,H904
 show-source = true
 exclude = .venv,.git,.tox,dist,doc,*lib/python*,.tmp,*egg,build,tools,.ropeproject,rally-scenarios