Adapt code from PyBBIO.RotaryEncoder

Add code to use as a basis for our QEP module from:
graycatlabs/PyBBIO/bbio/libraries/RotaryEncoder/rotary_encoder.py

Author: pdp7

Adafruit_BBIO/Encoder.py

@@ -11,8 +11,6 @@
 
 import os
 
-
-
 class QEP :
 
   def __init__(self, channel=1, debug=False):
@@ -45,7 +43,9 @@ def errMsg(self):
 
 
 class RotaryEncoder(object):
-  OCP_PATH = "/sys/TEST/TODO/"
+  # TODO: check that kernel 4.1+
+  # TODO: use config-pin to set qep mode
+  OCP_PATH = "/sys/devices/platform/ocp"
   _eqep_dirs = [
     '%s/48300000.epwmss/48300180.eqep' % OCP_PATH,
     '%s/48302000.epwmss/48302180.eqep' % OCP_PATH,
@@ -64,28 +64,24 @@ def __init__(self, eqep_num):
     eqep_num can be: EQEP0, EQEP1, EQEP2 or EQEP2b based on which pins \
     the rotary encoder is connected to.
     '''
+    print("RotaryEncoder(): eqep_num: {0}".format(eqep_num))
+    print("RotaryEncoder(): self._eqep_dirs[0]: {0}".format(self._eqep_dirs[0]))
+    print("RotaryEncoder(): self._eqep_dirs[1]: {0}".format(self._eqep_dirs[1]))
+    print("RotaryEncoder(): self._eqep_dirs[2]: {0}".format(self._eqep_dirs[2]))
+    print("RotaryEncoder(): self._eqep_dirs[eqep_num]: {0}".format(self._eqep_dirs[eqep_num]))
     assert 0 <= eqep_num <= 3 , "eqep_num must be between 0 and 3"
-    if eqep_num == 3:
-        overlay = "PyBBIO-eqep2b"
-    	eqep_num = 2
-    else:
-    	overlay = 'PyBBIO-eqep%i' % eqep_num
-
-    pwmss_overlay = "PyBBIO-epwmss%i" % eqep_num
-    #cape_manager.load(pwmss_overlay, auto_unload=False)
-    delay(10)
-    #cape_manager.load(overlay, auto_unload=False)
-    delay(250) # Give driver time to load 
     self.base_dir = self._eqep_dirs[eqep_num]
+    print("RotaryEncoder(): self.base_dir: {0}".format(self.base_dir))
     self.enable()
-    addToCleanup(self.disable)
 
   def enable(self):
     '''
     enable()
     Turns the eQEP hardware ON
     '''
     enable_file = "%s/enabled" % self.base_dir
+    print("enable(): enable_file: {0}".format(enable_file))
+    print("enable(): TODO: write 1 to enable_file")
     #return sysfs.kernelFileIO(enable_file, '1') 
 
   def disable(self):
@@ -94,6 +90,8 @@ def disable(self):
     Turns the eQEP hardware OFF
     '''
     enable_file = "%s/enabled" % self.base_dir
+    print("disable(): enable_file: {0}".format(enable_file))
+    print("disable(): TODO: write 0 to enable_file")
     #return sysfs.kernelFileIO(enable_file, '0')
 
   def setAbsolute(self):
@@ -104,6 +102,8 @@ def setAbsolute(self):
     decremented by the encoder's movement
     '''
     mode_file = "%s/mode" % self.base_dir
+    print("setAbsolute(): mode_file: {0}".format(mode_file))
+    print("setAbsolute(): TODO: write 0 to mode_file")
     #return sysfs.kernelFileIO(mode_file, '0')
 
   def setRelative(self):
@@ -113,6 +113,8 @@ def setRelative(self):
     The position is reset when the unit timer overflows.
     '''
     mode_file = "%s/mode" % self.base_dir
+    print("setRelative(): mode_file: {0}".format(mode_file))
+    print("setRelative(): TODO: write 1 to mode_file")
     #return sysfs.kernelFileIO(mode_file, '1')
 
   def getMode(self):
@@ -121,6 +123,8 @@ def getMode(self):
     Returns the mode the eQEP hardware is in.
     '''
     mode_file = "%s/mode" % self.base_dir
+    print("getMode(): mode_file: {0}".format(mode_file))
+    print("getMode(): TODO: read mode_file")
     #return sysfs.kernelFileIO(mode_file)
 
   def getPosition(self):
@@ -133,6 +137,8 @@ def getPosition(self):
     encoder at the last unit timer overflow.
     '''
     position_file = "%s/position" % self.base_dir
+    print("getPosition(): position_file: {0}".format(position_file))
+    print("getPosition(): TODO: read position_file")
     #return sysfs.kernelFileIO(position_file)
 
   def setFrequency(self,freq):
@@ -141,6 +147,12 @@ def setFrequency(self,freq):
     Set the frequency in Hz at which the driver reports new positions.
     '''
     period_file = "%s/period" % self.base_dir
+    print("setFrequency(): period_file: {0}".format(period_file))
+    print("setFrequency(): freq: {0}".format(period_file))
+    print("setFrequency(): freq: {0}".format(freq))
+    print("setFrequency(): 1000000000/freq: {0}".format(1000000000/freq))
+    print("setFrequency(): str(1000000000/freq)): {0}".format(str(1000000000/freq)))
+    print("setFrequency(): TODO: set period_file: {0}".format(str(1000000000/freq)))
     #return sysfs.kernelFileIO(period_file, str(1000000000/freq))
 
   def setPosition(self,val):