From 9aa2d314661dc97188681572e8cde662acf52a9b Mon Sep 17 00:00:00 2001
From: Sergey Spivak <sespivak@yandex.ru>
Date: Sun, 7 Aug 2022 20:51:15 +0400
Subject: [PATCH] i2c_packet: decoder for forming packets from i2c data

i2c_packet protocol decoder stacks with i2c PD and allows
to combine several data bytes from "START" i2c condition
until "STOP" and puts this data in a dedicated annotation.

Possible data formats for data output are hex, ascii, dec, bin and oct.
---
 decoders/i2c_packet/__init__.py |  28 +++++
 decoders/i2c_packet/pd.py       | 198 ++++++++++++++++++++++++++++++++
 2 files changed, 226 insertions(+)
 create mode 100644 decoders/i2c_packet/__init__.py
 create mode 100644 decoders/i2c_packet/pd.py

diff --git a/decoders/i2c_packet/__init__.py b/decoders/i2c_packet/__init__.py
new file mode 100644
index 00000000..41fa2511
--- /dev/null
+++ b/decoders/i2c_packet/__init__.py
@@ -0,0 +1,28 @@
+##
+## This file is part of the libsigrokdecode project.
+##
+## Copyright (C) 2022 Sergey Spivak <sespivak@yandex.ru>
+##
+## Permission is hereby granted, free of charge, to any person obtaining a copy
+## of this software and associated documentation files (the "Software"), to deal
+## in the Software without restriction, including without limitation the rights
+## to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+## copies of the Software, and to permit persons to whom the Software is
+## furnished to do so, subject to the following conditions:
+##
+## The above copyright notice and this permission notice shall be included in all
+## copies or substantial portions of the Software.
+##
+## THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+## IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+## FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+## AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+## LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+## OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+## SOFTWARE.
+
+'''
+Make data packets from I²C decoder data.
+'''
+
+from .pd import Decoder
diff --git a/decoders/i2c_packet/pd.py b/decoders/i2c_packet/pd.py
new file mode 100644
index 00000000..5c299c7f
--- /dev/null
+++ b/decoders/i2c_packet/pd.py
@@ -0,0 +1,198 @@
+##
+## This file is part of the libsigrokdecode project.
+##
+## Copyright (C) 2022 Sergey Spivak <sespivak@yandex.ru>
+##
+## Permission is hereby granted, free of charge, to any person obtaining a copy
+## of this software and associated documentation files (the "Software"), to deal
+## in the Software without restriction, including without limitation the rights
+## to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+## copies of the Software, and to permit persons to whom the Software is
+## furnished to do so, subject to the following conditions:
+##
+## The above copyright notice and this permission notice shall be included in all
+## copies or substantial portions of the Software.
+##
+## THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+## IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+## FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+## AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+## LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+## OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+## SOFTWARE.
+
+from collections import deque
+import sigrokdecode as srd
+
+'''
+OUTPUT_PYTHON format:
+
+Packet:
+[<ptype>, <pdata>]
+
+<ptype>:
+ - 'PACKET READ'  (ADDRESS READ followed by one or several
+                   DATA bytes until STOP or START REPEAT)
+ - 'PACKET WRITE' (ADDRESS WRITE followed by one or several
+                   DATA bytes until STOP or START REPEAT)
+ - 'TRANSACTION END' (End of transaction, due toi STOP bus condition)
+
+<pdata> is the tuple with slave address byte and tuple with data bytes
+if ptype is 'PACKET READ' or 'PACKET WRITE'.
+Slave addresses do not include bit 0 (the READ/WRITE indication bit).
+<pdata is None if ptype is 'TRANSACTION END'.
+'''
+
+class Ann:
+    DATA = 0
+
+class Decoder(srd.Decoder):
+    api_version = 3
+    id = 'i2c_packet'
+    name = 'I²C packet'
+    longname = 'I²C packet builder'
+    desc = 'Concatenate I²C data to packets'
+    license = 'mit'
+    inputs = ['i2c']
+    outputs = []
+    tags = ['Embedded/industrial']
+    options = (
+        {'id': 'format', 'desc': 'Data format', 'default': 'hex',
+            'values': ('ascii', 'dec', 'hex', 'oct', 'bin')},
+    )
+    annotations = (
+        ('data', 'Data'),
+    )
+    annotation_rows = (
+        ('packet', 'Packet', (Ann.DATA,)),
+    )
+
+    def __init__(self):
+        self.out_py = None
+        self.out_ann = None
+        self.packet_data = deque()
+        self.packet_str = ''
+        self.packet_str_short = ''
+        self.packet_ss = 0
+        self.packet_part_ss = 0
+        self.packet_es = 0
+        self.read_sign = False
+        self.address = 0
+        self.fmt = None
+        self.reset()
+
+    def start(self):
+        self.out_ann = self.register(srd.OUTPUT_ANN)
+        self.out_py = self.register(srd.OUTPUT_PYTHON)
+
+        format_name = self.options['format']
+        if format_name == 'hex':
+            self.fmt = '{:02X}'
+        elif format_name == 'dec':
+            self.fmt = '{:d}'
+        elif format_name == 'bin':
+            self.fmt = '{:08b}'
+        elif format_name == 'oct':
+            self.fmt = '{:03o}'
+        else:
+            self.fmt = None
+        self.packet_data = deque()
+
+    def reset(self):
+        self.packet_data.clear()
+        self.packet_str = ''
+        self.packet_str_short = ''
+        self.packet_ss = 0
+        self.packet_part_ss = 0
+        self.packet_es = 0
+        self.address = 0
+
+    def putg(self, ss, es, data):
+        """Put a graphical annotation."""
+        self.put(ss, es, self.out_ann, data)
+
+    def putp(self, ss, es, data):
+        """Put a python annotation."""
+        self.put(ss, es, self.out_py, data)
+
+    def format_data_value(self, v):
+        # Assume "is printable" for values from 32 to including 126,
+        # below 32 is "control" and thus not printable, above 127 is
+        # "not ASCII" in its strict sense, 127 (DEL) is not printable,
+        # fall back to hex representation for non-printables.
+        # (comment from same code of uart PD by Gerhard Sittig @gsigh)
+        if self.fmt is None:
+            if 32 <= v <= 126:
+                return chr(v)
+            return "[{:02X}]".format(v)
+        else:
+            return self.fmt.format(v)
+
+    def data_array_to_str(self, data_array):
+        if self.fmt:
+            str_array = [self.fmt.format(value) for value in data_array]
+            return ' '.join(str_array)
+        else:
+            str_array = [self.format_data_value(value) for value in data_array]
+            return ''.join(str_array)
+
+    def format_packet(self):
+        packet_str = "0x{:02X} {:}: ".format(
+            self.address,
+            'RD' if self.read_sign else 'WR',
+        ) + self.data_array_to_str(self.packet_data)
+
+        packet_str_short = packet_str[2:]
+
+        if self.packet_str:
+            packet_str = self.packet_str + ' [SR] ' + packet_str
+            packet_str_short = self.packet_str_short + ' [SR] ' + packet_str_short
+
+        return packet_str, packet_str_short
+
+    def handle_packet(self, start_repeat=False):
+        if not len(self.packet_data):
+            if not start_repeat:
+                self.reset()
+            return
+
+        packet_str, packet_str_short = self.format_packet()
+
+        ptype = 'PACKET READ' if self.read_sign else 'PACKET WRITE'
+        self.putp(self.packet_part_ss, self.packet_es,
+                  (ptype, (self.address, tuple(self.packet_data))))
+        if not start_repeat:
+            self.putp(self.packet_es, self.packet_es,
+                      ('TRANSACTION END', None))
+
+        if start_repeat:
+            self.packet_data.clear()
+            self.packet_str = packet_str
+            self.packet_str_short = packet_str_short
+        else:
+            packet_ss = self.packet_ss
+            self.putg(packet_ss, self.packet_es,
+                      [Ann.DATA, [packet_str, packet_str_short]])
+            self.reset()
+
+    def decode(self, ss, es, data):
+        ptype = data[0]
+        if ptype.startswith('DATA'):
+            self.packet_data.append(data[1])
+            self.packet_es = es
+        elif ptype.startswith('START'):
+            # If there is still data in the reception buffer, put the packet annotation
+            start_repeat = 'REPEAT' in ptype
+            self.handle_packet(start_repeat=start_repeat)
+            self.packet_part_ss = ss
+            if not start_repeat:
+                self.packet_ss = ss
+        elif ptype.startswith('ADDRESS'):
+            self.address = data[1]
+            self.read_sign = 'READ' in ptype
+            self.packet_es = es
+        elif ptype.endswith('ACK'):
+            self.packet_es = es
+        elif ptype == 'STOP':
+            self.packet_es = es
+            self.handle_packet()