import glob import sys import os import re try: import subprocess except ImportError: def popen(argv): try: si, so = os.popen4(' '.join(argv)) return so.read().strip() except: raise IOError('lsusb failed') else: def popen(argv): try: return subprocess.check_output(argv, stderr=subprocess.STDOUT).strip() except: raise IOError('lsusb failed') # The comports function is expected to return an iterable that yields tuples of # 3 strings: port name, human readable description and a hardware ID. # # as currently no method is known to get the second two strings easily, they # are currently just identical to the port name. # try to detect the OS so that a device can be selected... plat = sys.platform.lower() def read_line(filename): """help function to read a single line from a file. returns none""" try: f = open(filename) line = f.readline().strip() f.close() return line except IOError: return None def re_group(regexp, text): """search for regexp in text, return 1st group on match""" if sys.version < '3': m = re.search(regexp, text) else: # text is bytes-like m = re.search(regexp, text.decode('ascii', 'replace')) if m: return m.group(1) if plat[:5] == 'linux': # Linux (confirmed) # try to extract descriptions from sysfs. this was done by experimenting, # no guarantee that it works for all devices or in the future... def usb_sysfs_hw_string(sysfs_path): """given a path to a usb device in sysfs, return a string describing it""" bus, dev = os.path.basename(os.path.realpath(sysfs_path)).split('-') snr = read_line(sysfs_path+'/serial') if snr: snr_txt = ' SNR=%s' % (snr,) else: snr_txt = '' return 'USB VID:PID=%s:%s%s' % ( read_line(sysfs_path+'/idVendor'), read_line(sysfs_path+'/idProduct'), snr_txt ) def usb_lsusb_string(sysfs_path): base = os.path.basename(os.path.realpath(sysfs_path)) bus = base.split('-')[0] try: dev = int(open(os.path.join(sysfs_path, 'devnum')).readline().strip()) desc = popen(['lsusb', '-v', '-s', '%s:%s' % (bus, dev)]) # descriptions from device iManufacturer = re_group('iManufacturer\s+\w+ (.+)', desc) iProduct = re_group('iProduct\s+\w+ (.+)', desc) iSerial = re_group('iSerial\s+\w+ (.+)', desc) or '' # descriptions from kernel idVendor = re_group('idVendor\s+0x\w+ (.+)', desc) idProduct = re_group('idProduct\s+0x\w+ (.+)', desc) # create descriptions. prefer text from device, fall back to the others return '%s %s %s' % (iManufacturer or idVendor, iProduct or idProduct, iSerial) except IOError: return base def describe(device): """\ Get a human readable description. For USB-Serial devices try to run lsusb to get a human readable description. For USB-CDC devices read the description from sysfs. """ base = os.path.basename(device) # USB-Serial devices sys_dev_path = '/sys/class/tty/%s/device/driver/%s' % (base, base) if os.path.exists(sys_dev_path): sys_usb = os.path.dirname(os.path.dirname(os.path.realpath(sys_dev_path))) return usb_lsusb_string(sys_usb) # USB-CDC devices sys_dev_path = '/sys/class/tty/%s/device/interface' % (base,) if os.path.exists(sys_dev_path): return read_line(sys_dev_path) return base def hwinfo(device): """Try to get a HW identification using sysfs""" base = os.path.basename(device) if os.path.exists('/sys/class/tty/%s/device' % (base,)): # PCI based devices sys_id_path = '/sys/class/tty/%s/device/id' % (base,) if os.path.exists(sys_id_path): return read_line(sys_id_path) # USB-Serial devices sys_dev_path = '/sys/class/tty/%s/device/driver/%s' % (base, base) if os.path.exists(sys_dev_path): sys_usb = os.path.dirname(os.path.dirname(os.path.realpath(sys_dev_path))) return usb_sysfs_hw_string(sys_usb) # USB-CDC devices if base.startswith('ttyACM'): sys_dev_path = '/sys/class/tty/%s/device' % (base,) if os.path.exists(sys_dev_path): return usb_sysfs_hw_string(sys_dev_path + '/..') return 'n/a' # XXX directly remove these from the list? def comports(): devices = glob.glob('/dev/ttyS*') + glob.glob('/dev/ttyUSB*') + glob.glob('/dev/ttyACM*') return [(d, describe(d), hwinfo(d)) for d in devices] elif plat == 'cygwin': # cygwin/win32 def comports(): devices = glob.glob('/dev/com*') return [(d, d, d) for d in devices] elif plat[:7] == 'openbsd': # OpenBSD def comports(): devices = glob.glob('/dev/cua*') return [(d, d, d) for d in devices] elif plat[:3] == 'bsd' or \ plat[:7] == 'freebsd': def comports(): devices = glob.glob('/dev/cuad*') return [(d, d, d) for d in devices] elif plat[:6] == 'darwin': # OS X (confirmed) def comports(): """scan for available ports. return a list of device names.""" devices = glob.glob('/dev/tty.*') return [(d, d, d) for d in devices] elif plat[:6] == 'netbsd': # NetBSD def comports(): """scan for available ports. return a list of device names.""" devices = glob.glob('/dev/dty*') return [(d, d, d) for d in devices] elif plat[:4] == 'irix': # IRIX def comports(): """scan for available ports. return a list of device names.""" devices = glob.glob('/dev/ttyf*') return [(d, d, d) for d in devices] elif plat[:2] == 'hp': # HP-UX (not tested) def comports(): """scan for available ports. return a list of device names.""" devices = glob.glob('/dev/tty*p0') return [(d, d, d) for d in devices] elif plat[:5] == 'sunos': # Solaris/SunOS def comports(): """scan for available ports. return a list of device names.""" devices = glob.glob('/dev/tty*c') return [(d, d, d) for d in devices] elif plat[:3] == 'aix': # AIX def comports(): """scan for available ports. return a list of device names.""" devices = glob.glob('/dev/tty*') return [(d, d, d) for d in devices] else: # platform detection has failed... sys.stderr.write("""\ don't know how to enumerate ttys on this system. ! I you know how the serial ports are named send this information to ! the author of this module: sys.platform = %r os.name = %r pySerial version = %s also add the naming scheme of the serial ports and with a bit luck you can get this module running... """ % (sys.platform, os.name, serial.VERSION)) raise ImportError("Sorry: no implementation for your platform ('%s') available" % (os.name,)) # test if __name__ == '__main__': for port, desc, hwid in sorted(comports()): print "%s: %s [%s]" % (port, desc, hwid)