Omnia: sfpswitch refactor and add partial resets

Refacotr sfpswitch script in order to reuse code.
Add support for better --oneshot (set SFP, do not daemonize)
Add support for --resetled (Reset LED status, do not touch SFP mode,
do not daemonize).

sfpswitch/sfpswitch.py

@@ -5,139 +5,192 @@ import os
 import select
 import time
 
+debug = 1
+
 sfpdet_pin = 508
 sfpdis_pin = 505
 sfplos_pin = 507
 sfpflt_pin = 504
 
-gpio_export = '/sys/class/gpio/export'
 sfp_select = '/sys/devices/platform/soc/soc:internal-regs/f1034000.ethernet/net/eth1/phy_select'
-map = { 1: 'phy-def', 0: 'phy-sfp' }
+modemap = { 1: 'phy-def', 0: 'phy-sfp' }
 cmd_net_res = 'ip link set down dev eth1; /etc/init.d/network restart'
 cmd_safety_sleep = 2
 wan_led = '/sys/devices/platform/soc/soc:internal-regs/f1011000.i2c/i2c-0/i2c-1/1-002b/leds/omnia-led:wan'
 
-def write_once(path, value):
-	with open(path, 'w') as f:
-		f.write(value)
 
 
+def d(message):
+	if debug:
+		print message
 
-def gpio_dir(pin):
-	return '/sys/class/gpio/gpio%d/' % pin
 
-def init_gpio(pin):
-	if not (os.path.exists(gpio_dir(pin)) and
-		os.path.isdir(gpio_dir(pin))):
-		write_once(gpio_export, str(pin))
+class GPIO:
+	gpio_export = '/sys/class/gpio/export'
 
-	if not (os.path.exists(gpio_dir(pin)) and
-		os.path.isdir(gpio_dir(pin))):
-		raise Exception('Can not access %s' % gpio_dir(pin))
-	
+	def _sysfs_dir(self):
+		return '/sys/class/gpio/gpio%d/' % self.pin
 
-def init():
-	init_gpio(sfpdet_pin)
-	write_once(os.path.join(gpio_dir(sfpdet_pin), 'direction'), 'in')
-	write_once(os.path.join(gpio_dir(sfpdet_pin), 'edge'), 'both')
 
-	init_gpio(sfpdis_pin)
-	write_once(os.path.join(gpio_dir(sfpdis_pin), 'direction'), 'out')
-	write_once(os.path.join(gpio_dir(sfpdis_pin), 'value'), '0')
+	def __init__(self, pin, direction, edge=None, value=None):
+		self.pin = pin
+		
+		d = self._sysfs_dir()
+		if not (os.path.exists(d) and os.path.isdir(d)):
+			with open(GPIO.gpio_export, 'w') as f:
+				f.write(str(pin))
+
+		if not (os.path.exists(d) and os.path.isdir(d)):
+			raise Exception('Can not access %s' % d)
+
+		with open(os.path.join(d, 'direction'), 'w') as f:
+			f.write(direction)
+
+		if direction == 'in':
+			self.fd = open(os.path.join(d, 'value'), 'r')
+		elif direction == 'out':
+			self.fd = open(os.path.join(d, 'value'), 'w')
+		else:
+			raise Exception('Unknown direction %s' % direction)
+
+		if edge:
+			with open(os.path.join(d, 'edge'), 'w') as f:
+				f.write(edge)
+
+		if value:
+			self.fd.write(value)
+
+
+	def read(self):
+		self.fd.seek(0)
+		return int(self.fd.read().strip())
+
+
+	def write(self, val):
+		self.fd.write(val)
+
+
+	def getfd(self):
+		return self.fd.fileno()
+
+
+class LED:
+	def __init__(self, sysfsdir):
+		self.sysfsdir = sysfsdir
+
+
+	def set_autonomous(self, aut):
+		with open(os.path.join(self.sysfsdir, 'autonomous'), 'w') as f:
+			f.write('1' if aut else '0')
+
+
+	def set_brightness(self, bright):
+		with open(os.path.join(self.sysfsdir, 'brightness'), 'w') as f:
+			f.write('1' if bright else '0')
+
 
-	init_gpio(sfplos_pin)
-	write_once(os.path.join(gpio_dir(sfplos_pin), 'direction'), 'in')
-	write_once(os.path.join(gpio_dir(sfplos_pin), 'edge'), 'both')
 
-	init_gpio(sfpflt_pin)
-	write_once(os.path.join(gpio_dir(sfpflt_pin), 'direction'), 'in')
-	write_once(os.path.join(gpio_dir(sfpflt_pin), 'edge'), 'both')
 
-def set_led_mode(state):
-	if state == 1: # phy-def, autonomous blink
-		write_once(os.path.join(wan_led, 'autonomous'), '1')
-	elif state == 0: # phy-sfp, user blink
-		write_once(os.path.join(wan_led, 'autonomous'), '0')
-	else:
-		raise Exception("Unknown state %d. Can not happen." % state)
 
-def set_led_brightness(light=False):
-	write_once(os.path.join(wan_led, 'brightness'), '1' if light else '0')
+def set_nic_mode(mode, restart_net=True):
+	d('Switching mode to %s' % modemap[mode])
+
+	with open(sfp_select, 'r') as f:
+		c = f.read()
+		if c == modemap[mode]:
+			d("Current mode is %s . Noop." % c)
+			return
+		
+	with open(sfp_select, 'w') as f:
+		f.write(modemap[mode])
+
+	d("Switch success.")
 
-def do_switch(state, restart_net=True):
-	print 'Switching state to %s' % map[state]
-	write_once(sfp_select, map[state])
-	set_led_mode(state)
 	if restart_net:
 		time.sleep(cmd_safety_sleep)
+		d("Restarting net with command %s" % cmd_net_res)
 		os.system(cmd_net_res)
 
 
-def oneshot():
-	init()
-	f = open(os.path.join(gpio_dir(sfpdet_pin), 'value'), 'r')
-	state_last = int(f.read().strip())
-	do_switch(state_last, False)
+def led_change(led, sfplos, sfpflt):
+	led.set_brightness(False if sfplos.read() or sfpflt.read() else True)
 
 
-def run():
-	global state_last
+def led_init(mode, led, sfplos, sfpflt):
+	if mode == 1: # phy-def, autonomous blink
+		led.set_brightness(False)
+	led.set_autonomous(mode)
+	if mode == 0: # phy-sfp, user blink
+		led_change(led, sfplos, sfpflt)
 
-	def fdet_changed():
-		global state_last
-		fdet.seek(0)
-		state = int(fdet.read().strip())
-		if state != state_last:
-			state_last = state
-			do_switch(state)
 
-	def set_led():
-		global state_last
 
-		flos.seek(0)
-		fflt.seek(0)
-		los = int(flos.read().strip())
-		flt = int(fflt.read().strip())
+def mode_change(sfpdet, led, sfplos, sfpflt, restart_net=True):
+	m = sfpdet.read() # 0: phy-sfp, user blink; 1: phy-def, autonomous blink
+	set_nic_mode(m, restart_net)
+	led_init(m, led, sfplos, sfpflt)
 
-		set_led_mode(state_last)
 
-		if los or flt:
-			set_led_brightness(False)
-		else:
-			set_led_brightness(True)
+
+# Frontend functions
+
+def reset_led():
+	sfpdet = GPIO(sfpdet_pin, 'in', edge='both')
+	sfplos = GPIO(sfplos_pin, 'in', edge='both')
+	sfpflt = GPIO(sfpflt_pin, 'in', edge='both')
+	led = LED(wan_led)
+
+	m = sfpdet.read() # 0: phy-sfp, user blink; 1: phy-def, autonomous blink
+	led.set_autonomous(m)
+	led_change(led, sfplos, sfpflt)
+
+
+def oneshot():
+	sfpdet = GPIO(sfpdet_pin, 'in', edge='both')
+	sfpdis = GPIO(sfpdis_pin, 'out', value='0')
+	sfplos = GPIO(sfplos_pin, 'in', edge='both')
+	sfpflt = GPIO(sfpflt_pin, 'in', edge='both')
+	led = LED(wan_led)
+
+	mode_change(sfpdet, led, sfplos, sfpflt, False)
+
+
+def run():
+	sfpdet = GPIO(sfpdet_pin, 'in', edge='both')
+	sfpdis = GPIO(sfpdis_pin, 'out', value='0')
+	sfplos = GPIO(sfplos_pin, 'in', edge='both')
+	sfpflt = GPIO(sfpflt_pin, 'in', edge='both')
+	led = LED(wan_led)
+
+	def fdet_changed():
+		d("sfpdet change detected: %d" % sfpdet.read())
+		mode_change(sfpdet, led, sfplos, sfpflt)
 
 	def flos_changed():
-		set_led()
+		d("sfplos change detected: %d " % sfplos.read())
+		led_change(led, sfplos, sfpflt)
 
 	def fflt_changed():
-		set_led()
+		d("sfpflt change detected: %d" % sfpflt.read())
+		led_change(led, sfplos, sfpflt)
 
-	init()
-
-	fdet = open(os.path.join(gpio_dir(sfpdet_pin), 'value'), 'r')
-	flos = open(os.path.join(gpio_dir(sfplos_pin), 'value'), 'r')
-	fflt = open(os.path.join(gpio_dir(sfpflt_pin), 'value'), 'r')
+	mode_change(sfpdet, led, sfplos, sfpflt, True)
 
 	po = select.epoll()
-	po.register(fdet, select.EPOLLPRI)
-	po.register(flos, select.EPOLLPRI)
-	po.register(fflt, select.EPOLLPRI)
-
-	state_last = int(fdet.read().strip())
-	do_switch(state_last)
-	set_led()
+	po.register(sfpdet.getfd(), select.EPOLLPRI)
+	po.register(sfplos.getfd(), select.EPOLLPRI)
+	po.register(sfpflt.getfd(), select.EPOLLPRI)
 
 	# main loop
 	while 1:
 		events = po.poll(60000)
 		for e in events:
 			ef = e[0] # event file descriptor
-			time.sleep(cmd_safety_sleep)
-			if ef == fdet.fileno():
+			if ef == sfpdet.getfd():
 				fdet_changed()
-			elif ef == flos.fileno():
+			elif ef == sfplos.getfd():
 				flos_changed()
-			elif ef == fflt.fileno():
+			elif ef == sfpflt.getfd():
 				fflt_changed()
 			else:
 				raise Exception("Unknown FD. Can not happen.")
@@ -161,6 +214,7 @@ def help():
 
 --oneshot : set the PHY and restart network, then exit
 --nodaemon : run in foreground
+--resetled : reset the LED according to current mode, then exit
 NO PARAM : daemonize and wait for PHY change
 """
 
@@ -168,6 +222,8 @@ def main():
 	if len(sys.argv) > 1:
 		if sys.argv[1] == '--oneshot':
 			oneshot()
+		elif sys.argv[1] == '--resetled':
+			reset_led()
 		elif sys.argv[1] == '--nodaemon':
 			run()
 		elif sys.argv[1] == '--help':