alvaBC6 driver: Support auto-detection.

The ALVA library still scans for devices itself at this stage, so it's slower than it could be. It should be possible to improve this in future.

source/bdDetect.py

@@ -215,6 +215,12 @@ def arePossibleDevicesForDriver(driver):
 		return False
 
 ### Detection data
+# alvaBC6
+addUsbDevices("alvaBC6", {
+	"VID_0798&PID_0640", # BC640
+	"VID_0798&PID_0680", # BC680
+})
+addBluetoothComPorts("alvaBC6", lambda m: m.name.startswith("ALVA "))
 # baum
 addUsbDevices("baum", {
 	"VID_0403&PID_FE70", # Vario 40

source/brailleDisplayDrivers/alvaBC6.py

@@ -2,7 +2,7 @@
 #A part of NonVisual Desktop Access (NVDA)
 #This file is covered by the GNU General Public License.
 #See the file COPYING for more details.
-#Copyright (C) 2009-2011 Optelec B.V. <http://www.optelec.com/>, James Teh <jamie@jantrid.net>
+#Copyright (C) 2009-2013 Optelec B.V., NV Access Limited
 
 import braille
 import queueHandler
@@ -12,6 +12,7 @@
 import time
 import config
 import inputCore
+import bdDetect
 
 ALVA_RELEASE_MASK = 0x8000
 
@@ -46,9 +47,9 @@ class BrailleDisplayDriver(braille.BrailleDisplayDriver):
 
 	@classmethod
 	def check(cls):
-		return bool(AlvaLib)
+		return bool(AlvaLib) and bdDetect.arePossibleDevicesForDriver(cls.name)
 
-	def __init__(self):
+	def __init__(self, port=None):
 		super(BrailleDisplayDriver,self).__init__()
 		log.debug("ALVA BC6xx Braille init")
 		_AlvaNumDevices=c_int(0)