+++ /dev/null
-##
-## This file is part of the sigrok project.
-##
-## Copyright (C) 2012 Bert Vermeulen <bert@biot.com>
-## Copyright (C) 2012 Uwe Hermann <uwe@hermann-uwe.de>
-##
-## 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/>.
-##
-
-# Generic I2C filtering protocol decoder
-
-# TODO: Support for filtering out multiple slave/direction pairs?
-
-import sigrokdecode as srd
-
-class Decoder(srd.Decoder):
- api_version = 1
- id = 'i2cfilter'
- name = 'I2C filter'
- longname = 'I2C filter'
- desc = 'Filter out addresses/directions in an I2C stream.'
- license = 'gplv3+'
- inputs = ['i2c']
- outputs = ['i2c']
- probes = []
- optional_probes = []
- options = {
- 'address': ['Address to filter out of the I2C stream', 0],
- 'direction': ['Direction to filter (read/write/both)', 'both']
- }
- annotations = []
-
- def __init__(self, **kwargs):
- self.state = None
- self.curslave = -1
- self.curdirection = None
- self.packets = [] # Local cache of I2C packets
-
- def start(self, metadata):
- self.out_proto = self.add(srd.OUTPUT_PROTO, 'i2c')
- if self.options['address'] not in range(0, 127 + 1):
- raise Exception('Invalid slave (must be 0..127).')
- if self.options['direction'] not in ('both', 'read', 'write'):
- raise Exception('Invalid direction (valid: read/write/both).')
-
- def report(self):
- pass
-
- # Grab I2C packets into a local cache, until an I2C STOP condition
- # packet comes along. At some point before that STOP condition, there
- # will have been an ADDRESS READ or ADDRESS WRITE which contains the
- # I2C address of the slave that the master wants to talk to.
- # If that slave shall be filtered, output the cache (all packets from
- # START to STOP) as proto 'i2c', otherwise drop it.
- def decode(self, ss, es, data):
-
- cmd, databyte = data
-
- # Add the I2C packet to our local cache.
- self.packets.append([ss, es, data])
-
- if cmd in ('ADDRESS READ', 'ADDRESS WRITE'):
- self.curslave = databyte
- self.curdirection = cmd[8:].lower()
- elif cmd in ('STOP', 'START REPEAT'):
- # If this chunk was not for the correct slave, drop it.
- if self.options['address'] == 0:
- pass
- elif self.curslave != self.options['address']:
- self.packets = []
- return
-
- # If this chunk was not in the right direction, drop it.
- if self.options['direction'] == 'both':
- pass
- elif self.options['direction'] != self.curdirection:
- self.packets = []
- return
-
- # TODO: START->STOP chunks with both read and write (Repeat START)
- # Otherwise, send out the whole chunk of I2C packets.
- for p in self.packets:
- self.put(p[0], p[1], self.out_proto, p[2])
-
- self.packets = []
- else:
- pass # Do nothing, only add the I2C packet to our cache.
-