--- /dev/null
+##
+## This file is part of the sigrok project.
+##
+## Copyright (C) 2012 Bert Vermeulen <bert@biot.com>
+##
+## This program is free software; you can redistribute it and/or modify
+## it under the terms of the GNU General Public License as published by
+## the Free Software Foundation; either version 3 of the License, or
+## (at your option) any later version.
+##
+## This program is distributed in the hope that it will be useful,
+## but WITHOUT ANY WARRANTY; without even the implied warranty of
+## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+## GNU General Public License for more details.
+##
+## You should have received a copy of the GNU General Public License
+## along with this program; if not, see <http://www.gnu.org/licenses/>.
+##
+
+pkgdatadir = $(DECODERS_DIR)/i2cfilter
+
+dist_pkgdata_DATA = __init__.py i2cfilter.py
+
+CLEANFILES = *.pyc
+
--- /dev/null
+##
+## This file is part of the sigrok project.
+##
+## Copyright (C) 2012 Bert Vermeulen <bert@biot.com>
+##
+## This program is free software; you can redistribute it and/or modify
+## it under the terms of the GNU General Public License as published by
+## the Free Software Foundation; either version 3 of the License, or
+## (at your option) any later version.
+##
+## This program is distributed in the hope that it will be useful,
+## but WITHOUT ANY WARRANTY; without even the implied warranty of
+## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+## GNU General Public License for more details.
+##
+## You should have received a copy of the GNU General Public License
+## along with this program; if not, see <http://www.gnu.org/licenses/>.
+##
+
+'''
+Takes input from the I2C protocol decoder and filters out traffic from/to
+a single address on the I2C bus.
+
+It then outputs the filtered data one byte at a time as OUTPUT_PROTO up the
+protocol decoder stack. No annotations are output.
+
+The I2C address to filter out should be passed in as an option 'address', as
+an integer. A specific read or write operation can be selected with the
+'direction' option, which should be 'read' or 'write'.
+
+Both of these are optional; if no options are specified the entire payload
+of the I2C session will be output.
+'''
+
+from .i2cfilter import *
+
--- /dev/null
+##
+## This file is part of the sigrok project.
+##
+## Copyright (C) 2012 Bert Vermeulen <bert@biot.com>
+##
+## This program is free software; you can redistribute it and/or modify
+## it under the terms of the GNU General Public License as published by
+## the Free Software Foundation; either version 3 of the License, or
+## (at your option) any later version.
+##
+## This program is distributed in the hope that it will be useful,
+## but WITHOUT ANY WARRANTY; without even the implied warranty of
+## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+## GNU General Public License for more details.
+##
+## You should have received a copy of the GNU General Public License
+## along with this program; if not, see <http://www.gnu.org/licenses/>.
+##
+
+import sigrokdecode as srd
+
+
+class Decoder(srd.Decoder):
+ api_version = 1
+ id = 'i2cfilter'
+ name = 'I2C filter'
+ longname = 'I2C filter'
+ desc = 'Filter out specific addresses/directions in an I2C stream.'
+ license = 'gplv3+'
+ inputs = ['i2c']
+ outputs = []
+ options = {
+ 'address': ['Address to filter out of the I2C stream', 0],
+ 'direction': ['Direction to filter (read/write)', '']
+ }
+
+ def __init__(self, **kwargs):
+ self.state = None
+
+ def start(self, metadata):
+ self.out_proto = self.add(srd.OUTPUT_PROTO, 'i2cdata')
+ if self.options['direction'] not in ('', 'read', 'write'):
+ raise Exception("Invalid direction: expected 'read' or 'write'")
+
+ def decode(self, ss, es, data):
+ try:
+ cmd, data, ack_bit = data
+ except Exception as e:
+ raise Exception('Malformed I2C input: %s' % str(e)) from e
+
+ # Whichever state we're in, these always reset the state machine.
+ # This should make it easier to deal with corrupt data etc.
+ if cmd in ('START', 'START REPEAT'):
+ self.state = 'start'
+ return
+ if cmd == 'STOP':
+ self.state = None
+ return
+
+ if self.state == 'start':
+ # Start of a transfer, see if we want this one.
+ if cmd == 'ADDRESS READ' and self.options['direction'] == 'write':
+ return
+ elif cmd == 'ADDRESS WRITE' and self.options['direction'] == 'read':
+ return
+ elif cmd in ('ADDRESS READ', 'ADDRESS WRITE'):
+ if self.options['address'] in (0, data):
+ # We want this tranfer.
+ self.state = 'transfer'
+ elif self.state == 'transfer':
+ if cmd in ('DATA READ', 'DATA WRITE'):
+ self.put(ss, es, self.out_proto, data)
+ else:
+ raise Exception('Invalid state: %s' % self.state)
+
+
projects / libsigrokdecode.git / commitdiff