From 0fd5edc6515f9b48ade95ee8331664158d2d8854 Mon Sep 17 00:00:00 2001
From: Udo Waechter <udo@maketank.net>
Date: Sun, 24 May 2020 15:16:54 +0200
Subject: [PATCH] hardware specific states

---
 hardware/init.sls                          |  4 ++
 hardware/raspberrypi/fan/files/fan_ctrl.py | 82 ++++++++++++++++++++++
 hardware/raspberrypi/fan/init.sls          | 11 +++
 hardware/raspberrypi/init.sls              | 12 ++++
 4 files changed, 109 insertions(+)
 create mode 100644 hardware/init.sls
 create mode 100644 hardware/raspberrypi/fan/files/fan_ctrl.py
 create mode 100644 hardware/raspberrypi/fan/init.sls
 create mode 100644 hardware/raspberrypi/init.sls

diff --git a/hardware/init.sls b/hardware/init.sls
new file mode 100644
index 0000000..bfb0ce4
--- /dev/null
+++ b/hardware/init.sls
@@ -0,0 +1,4 @@
+{% if grains(os) is "Raspbian" %}
+include:
+  - .raspberrypi
+{% endif %}
diff --git a/hardware/raspberrypi/fan/files/fan_ctrl.py b/hardware/raspberrypi/fan/files/fan_ctrl.py
new file mode 100644
index 0000000..1ce9750
--- /dev/null
+++ b/hardware/raspberrypi/fan/files/fan_ctrl.py
@@ -0,0 +1,82 @@
+#!/usr/bin/python
+# -*- coding: utf-8 -*-
+
+import RPi.GPIO as GPIO
+from datetime import date
+from os import getenv
+import time
+import sys
+
+# Configuration
+FAN_PIN = getenv(RPI_FAN_PIN, 21)  # BCM pin used to drive transistor's base
+WAIT_TIME = getenv(RPI_FAN_WAITTIME, 5)  # [s] Time to wait between each refresh
+FAN_MIN = getenv(RPI_FAN_MIN, 60)  # [%] Fan minimum speed.
+PWM_FREQ = getenv(RPI_FAN_PWMFREW, 50000)  # [Hz] Change this value if fan has strange behavior
+# Fan speed will change only of the difference of temperature is higher than hysteresis
+hyst = getenv(RPI_FAN_HYST, 5)
+
+# Configurable temperature and fan speed steps
+tempSteps = [50, 55, 57, 60, 68, 70]  # [°C]
+speedSteps = [0, 60, 65, 70, 80, 100]  # [%]
+# tempSteps = [40, 45]
+# speedSteps = [0, 100]
+
+# Setup GPIO pin
+GPIO.setmode(GPIO.BCM)
+GPIO.setup(FAN_PIN, GPIO.OUT, initial=GPIO.LOW)
+fan = GPIO.PWM(FAN_PIN, PWM_FREQ)
+fan.start(0)
+
+i = 0
+cpuTemp = 0
+fanSpeed = 0
+cpuTempOld = 0
+fanSpeedOld = 0
+
+print("%s Temp: %s, Fan: %s" % (date.today(), cpuTemp, fanSpeed))
+
+# We must set a speed value for each temperature step
+if len(speedSteps) != len(tempSteps):
+    print("Numbers of temp steps and speed steps are different")
+    exit(0)
+
+try:
+    while 1:
+        # Read CPU temperature
+        cpuTempFile = open("/sys/class/thermal/thermal_zone0/temp", "r")
+        cpuTemp = float(cpuTempFile.read()) / 1000
+        cpuTempFile.close()
+        print("%s Temp: %s, Fan: %s" % (date.today(), cpuTemp, fanSpeed))
+        # Calculate desired fan speed
+        if abs(cpuTemp - cpuTempOld) > hyst:
+            # Below first value, fan will run at min speed.
+            if cpuTemp < tempSteps[0]:
+                fanSpeed = speedSteps[0]
+            # Above last value, fan will run at max speed
+            elif cpuTemp >= tempSteps[len(tempSteps) - 1]:
+                fanSpeed = speedSteps[len(tempSteps) - 1]
+            # If temperature is between 2 steps, fan speed is calculated by linear interpolation
+            else:
+                for i in range(0, len(tempSteps) - 1):
+                    if (cpuTemp >= tempSteps[i]) and (cpuTemp < tempSteps[i + 1]):
+                        fanSpeed = round((speedSteps[i + 1] - speedSteps[i])
+                                         / (tempSteps[i + 1] - tempSteps[i])
+                                         * (cpuTemp - tempSteps[i])
+                                         +speedSteps[i], 1)
+
+            if fanSpeed != fanSpeedOld:
+                if (fanSpeed != fanSpeedOld
+                        and (fanSpeed >= FAN_MIN or fanSpeed == 0)):
+                    fan.ChangeDutyCycle(fanSpeed)
+                    fanSpeedOld = fanSpeed
+                    print("%s Temp: %s, Fan: %s" % (date.today(), cpuTemp, fanSpeed))
+            cpuTempOld = cpuTemp
+
+        # Wait until next refresh
+        time.sleep(WAIT_TIME)
+
+# If a keyboard interrupt occurs (ctrl + c), the GPIO is set to 0 and the program exits.
+finally:
+    print("Fan ctrl interrupted by keyboard")
+    GPIO.cleanup()
+    sys.exit()
diff --git a/hardware/raspberrypi/fan/init.sls b/hardware/raspberrypi/fan/init.sls
new file mode 100644
index 0000000..0e43970
--- /dev/null
+++ b/hardware/raspberrypi/fan/init.sls
@@ -0,0 +1,11 @@
+
+file-fan-control:
+  file:
+    - managed
+    - name: /usr/local/bin/fan_ctrl.py
+    - source: salt://states/hardware/raspberrypi/fan/files/fan_ctrl.py
+    - user: root
+    - group: root
+    - mode: 0755
+
+
diff --git a/hardware/raspberrypi/init.sls b/hardware/raspberrypi/init.sls
new file mode 100644
index 0000000..7dab148
--- /dev/null
+++ b/hardware/raspberrypi/init.sls
@@ -0,0 +1,12 @@
+ 
+{%
+set has_fan = salt['pillar.get'](
+  'hardware:raspberrypi:has_fan',
+  default=False
+)
+%}
+
+{%- if has_fan %}
+include:
+  - .fan
+{%- endif %}