moved raspberry specific settings to raspberrypi role

roles/raspberrypi/tasks/main.yml

@@ -0,0 +1,48 @@
+---
+- name: Test for raspberry pi /proc/cpuinfo
+  command: grep -E "Raspberry Pi|BCM2708|BCM2709|BCM2835|BCM2836" /proc/cpuinfo
+  register: grep_cpuinfo_raspberrypi
+  failed_when: false
+  changed_when: false
+
+- name: Test for raspberry pi /proc/device-tree/model
+  command: grep -E "Raspberry Pi" /proc/device-tree/model
+  register: grep_device_tree_model_raspberrypi
+  failed_when: false
+  changed_when: false
+
+- name: Set raspberry_pi fact to true
+  set_fact:
+    raspberry_pi: true
+  when:
+    grep_cpuinfo_raspberrypi.rc == 0 or grep_device_tree_model_raspberrypi.rc == 0
+
+- name: Set detected_distribution to Raspbian
+  set_fact:
+    detected_distribution: Raspbian
+  when:
+   - raspberry_pi|default(false)
+   - ansible_facts.lsb.id|default("") == "Raspbian" or ansible_facts.lsb.description|default("") is match("[Rr]aspbian.*")
+
+- name: Set detected_distribution to Raspbian (ARM64 on Debian Buster)
+  set_fact:
+    detected_distribution: Raspbian
+  when:
+    - ansible_facts.architecture is search("aarch64")
+    - raspberry_pi|default(false)
+    - ansible_facts.lsb.description|default("") is match("Debian.*buster")
+
+- name: Set detected_distribution_major_version
+  set_fact:
+    detected_distribution_major_version: "{{ ansible_facts.lsb.major_release }}"
+  when:
+    - detected_distribution | default("") == "Raspbian"
+
+- name: execute OS related tasks on the Raspberry Pi
+  include_tasks: "{{ item }}"
+  with_first_found:
+    - "prereq/{{ detected_distribution }}-{{ detected_distribution_major_version }}.yml"
+    - "prereq/{{ detected_distribution }}.yml"
+    - "prereq/{{ ansible_distribution }}-{{ ansible_distribution_major_version }}.yml"
+    - "prereq/{{ ansible_distribution }}.yml"
+    - "prereq/default.yml"

roles/raspberrypi/tasks/prereq/Raspbian.yml

@@ -1,13 +1,4 @@
 ---
-- name: Test for Raspbian
-  set_fact:
-    raspbian: '{% if
-      ( ansible_facts.architecture is search("arm") and
-        ansible_facts.lsb.description is match("[Rr]aspbian.*[Bb]uster") ) or
-      ( ansible_facts.architecture is search("aarch64") and
-        ansible_facts.lsb.description is match("Debian.*buster") or
-        ansible_facts.lsb.description is match("[Rr]aspbian.*[Bb]uster") ) %}true{% else %}false{% endif %}'
-
 - name: Activating cgroup support
   lineinfile:
     path: /boot/cmdline.txt
@@ -15,13 +6,10 @@
     line: '\1 cgroup_enable=cpuset cgroup_memory=1 cgroup_enable=memory'
     backrefs: true
   notify: reboot
-  when:
-    - raspbian is true
 
 - name: Flush iptables before changing to iptables-legacy
   iptables:
     flush: true
-  when: raspbian
   changed_when: false   # iptables flush always returns changed
 
 - name: Changing to iptables-legacy
@@ -29,11 +17,9 @@
     path: /usr/sbin/iptables-legacy
     name: iptables
   register: ip4_legacy
-  when: raspbian
 
 - name: Changing to ip6tables-legacy
   alternatives:
     path: /usr/sbin/ip6tables-legacy
     name: ip6tables
   register: ip6_legacy
-  when: raspbian

roles/raspberrypi/tasks/prereq/default.yml

@@ -0,0 +1 @@
+---

site.yml

@@ -6,8 +6,7 @@
   roles:
     - role: prereq
     - role: download
-    - role: raspbian
-    - role: ubuntu
+    - role: raspberrypi
 
 - hosts: master
   become: yes