rpibmc/bmcd

#!/usr/bin/env python

#
# bmcd - BMC Daemon program
#
# This program works as a background daemon for the RPi BMC. It provides
# functionality to interface with the GPIOs in an asynchronous way via two
# pipes, one read-only and one write-only from the outside perspective. The read
# pipe provides the current system power status while the write pipe listens
# for commands.
#
# Part of the RPiBMC project - (c)2017 Joshua Boniface
# This software is licenced under the terms of the GNU GPL version 3. For
# details please see LICENSE
#

import socket, os, time, struct
from threading import Thread, Event
from daemon import runner
import RPi.GPIO as GPIO

# These are GPIOs 1-4
gpio_rsw = 17
gpio_psw = 18
gpio_state = 27
gpio_pled = 22

# The pipes and PID file (sorry I manage this here...)
bmcd_state = '/run/bmcd/bmcd.state'
bmcd_cmd = '/run/bmcd/bmcd.cmd'
pidfile = '/run/bmcd/bmcd.pid'

# Event for LED flash (i.e. locator)
is_pled_flashing = Event()

# Turn the power LED on
def powerled_on():
    GPIO.output(gpio_pled, 1)

# Turn the power LED off
def powerled_off():
    GPIO.output(gpio_pled, 0)

# Flash the power LED
def powerled_flash(is_pled_flashing):
    while is_pled_flashing.isSet():
        GPIO.output(gpio_pled, 1)
        time.sleep(1)
        GPIO.output(gpio_pled, 0)
        time.sleep(1)
    is_pled_flashing.clear()
    return

# Press the power button
def powersw_press():
    GPIO.output(gpio_psw, 1)
    time.sleep(0.5)
    GPIO.output(gpio_psw, 0)

# Hold the power button (8 seconds)
def powersw_hold():
    GPIO.output(gpio_psw, 1)
    time.sleep(8)
    GPIO.output(gpio_psw, 0)

# Press the reset button
def resetsw_press():
    GPIO.output(gpio_rsw, 1)
    time.sleep(0.5)
    GPIO.output(gpio_rsw, 0)

# Turn on the locator (subthread)
def locate_on():
    is_pled_flashing.set()
    t = Thread(name='non-block', target=powerled_flash, args=(is_pled_flashing,))
    t.start()

# Turn off the locator
def locate_off():
    is_pled_flashing.clear()

# Main loop to read a command from the pipe
def readcmd():
    fcmd = open(bmcd_cmd, 'r+', 0)
    while True:
        line = fcmd.readline()
        try:
            globals()[line.rstrip()]()
        except:
            pass

#  Main loop to write power state to the pipe
def writestate(is_pled_flashing):
    while True:
        state_now = GPIO.input(gpio_state)
    	fstate = open(bmcd_state, 'w+', 0)
        fstate.write(str(state_now) + '\n')
	fstate.close()
        if not is_pled_flashing.isSet():
            if state_now == 1:
                powerled_on()
            else:
                powerled_off()

        time.sleep(1)
       
# Main app definiton - sets default states and runs main loop
class App():
    def __init__(self):
        self.stdin_path = '/dev/null'
        self.stdout_path = '/var/log/bmcd.log'
        self.stderr_path = '/var/log/bmcd.log'
        self.pidfile_path = pidfile
        self.pidfile_timeout = 5
    def run(self):
        if not os.path.exists(bmcd_state):
	    os.mkfifo(bmcd_state) 
        if not os.path.exists(bmcd_cmd):
	    os.mkfifo(bmcd_cmd)

        GPIO.setmode(GPIO.BCM)
        GPIO.setup(gpio_state, GPIO.IN)
        GPIO.setup(gpio_psw, GPIO.OUT)
        GPIO.setup(gpio_rsw, GPIO.OUT)
        GPIO.setup(gpio_pled, GPIO.OUT)

        t1 = Thread(target=readcmd)
        t2 = Thread(target=writestate, args=(is_pled_flashing,))
        t1.setDaemon(True)
        t2.setDaemon(True)
        t1.start()
        t2.start()
        while True:
            pass

# App definition - start it up
app = App()
daemon_runner = runner.DaemonRunner(app)
daemon_runner.do_action()