Eeprom protobuf (#131)

* protobuf implementation

#126 #124

* test added

* pylint fix and update dependencies

* Update requirements_test.txt

* delete Todos

* suggested fixes

* suggested name fix

Author: sjpark608

requirements_test.txt

@@ -12,3 +12,4 @@ tomli==2.0.1
 bitstring==3.1.9
 pytest-mock==3.7.0
 pytest-cov==3.0.0
+protobuf==3.20.3

setup.py

@@ -25,5 +25,5 @@
     packages=setuptools.find_packages(where="src", exclude=["test_edgepi"]),
     package_dir={"": "src"},
     python_requires=">=3.6",
-    install_requires=["python-periphery >= 2.3.0", "bitstring >= 3.1.9"],
+    install_requires=["python-periphery >= 2.3.0", "bitstring >= 3.1.9", "protobuf==3.20.*"],
 )

src/edgepi/calibration/edgepi_eeprom.py

@@ -3,11 +3,15 @@
 import logging
 import math
 
-from edgepi.calibration.eeprom_constants import EEPROMInfo
+from edgepi.calibration.eeprom_constants import (
+    EEPROMInfo,
+    EdgePiMemoryInfo,
+    MessageFieldNumber,
+    EdgePiEEPROMData)
+from edgepi.calibration.eeprom_mapping_pb2 import EepromLayout
 from edgepi.peripherals.i2c import I2CDevice
 
-#TODO: Maybe use protobuff
-#TODO: EEPROM should return structured data class of parameters to calibration class.
+
 class EdgePiEEPROM(I2CDevice):
     '''
     Helper class to read eeprom using I2C
@@ -16,6 +20,7 @@ class EdgePiEEPROM(I2CDevice):
 
     def __init__(self):
         self.log = logging.getLogger(__name__)
+        self.eeprom_layout = EepromLayout()
         super().__init__(self.__dev_path)
 
     def __pack_mem_address(self, page_addr: int = None, byte_addr: int = None):
@@ -44,6 +49,67 @@ def __byte_address_generation(self, memory_address: int = None):
         self.log.debug(f'Page address = {page_addr}, byte Address = {byte_addr}')
         return page_addr, byte_addr
 
+    def __allocated_memory(self):
+        '''
+        The first two bytes represenst the allocated memory in Edgepi reserved memory space. This
+        function returns the length of memory to read.
+        Args:
+            N/A
+        Return:
+            length (int): size of memory to read
+        '''
+        length = self.sequential_read(EdgePiMemoryInfo.USED_SPACE.value, 2)
+        return (length[0]<<8)| length[1]
+
+    def __read_edgepi_reserved_memory(self):
+        '''
+        Read Edgepi reserved memory space to retreive parameters. This function will return byte
+        strings, that can be converted into protocol buffer message format
+        Args:
+            N/A
+        Return:
+            Byte_string (bytes): strings of bytes read from the eeprom
+        '''
+        mem_size = self.__allocated_memory()
+        buff_list = self.sequential_read(EdgePiMemoryInfo.BUFF_START.value, mem_size)
+        return bytes(buff_list)
+
+    def get_message_of_interest(self, msg: MessageFieldNumber = None):
+        """
+        This function filters out the message according to the specified field number passed as
+        parameter.
+        Args:
+            msg (MessageFieldNumber): protocol buffer message field index number for ListFields()
+            function
+        Return:
+            pb message specified by the message field number. ex) if message field of DAC is passed,
+            the dac message will be returned
+        """
+        self.eeprom_layout.ParseFromString(self.__read_edgepi_reserved_memory())
+        return self.eeprom_layout.ListFields()[msg.value - 1][1]
+
+    def get_edgepi_reserved_data(self):
+        """
+        Read Edgepi reserved memory space and populate dataclass
+        Args:
+            N/A
+        Return:
+            eeprom_data (EdgePiEEPROMData): dataclass containing eeprom values
+        """
+        # pylint: disable=no-member
+        self.eeprom_layout.ParseFromString(self.__read_edgepi_reserved_memory())
+        eeprom_data = EdgePiEEPROMData()
+        eeprom_data.dac_calib_parms=eeprom_data.message_to_list(self.eeprom_layout.dac)
+        eeprom_data.adc_calib_parms=eeprom_data.message_to_list(self.eeprom_layout.adc)
+        eeprom_data.rtd_calib_parms=eeprom_data.message_to_list(self.eeprom_layout.rtd)
+        eeprom_data.tc_calib_parms=eeprom_data.message_to_list(self.eeprom_layout.tc)
+        eeprom_data.config_key=eeprom_data.keys_to_str(self.eeprom_layout.config_key)
+        eeprom_data.data_key=eeprom_data.keys_to_str(self.eeprom_layout.data_key)
+        eeprom_data.serial= self.eeprom_layout.serial_number
+        eeprom_data.model= self.eeprom_layout.model
+        eeprom_data.client_id= self.eeprom_layout.client_id
+        return eeprom_data
+
     def sequential_read(self, mem_addr: int = None, length: int = None):
         '''
         Read operation reads the specified number of memory location starting from provided address.

src/edgepi/calibration/eeprom_constants.py

@@ -1,6 +1,8 @@
 '''Address map of eeprom'''
 
 from enum import Enum
+from dataclasses import dataclass
+from edgepi.calibration.eeprom_mapping_pb2 import EepromLayout
 
 class EEPROMInfo(Enum):
     """
@@ -19,13 +21,13 @@ class ModuleNames(Enum):
     RTD = 0x2
     TC = 0x3
 
+# TODO: to be deleted once protobuf is implemented
 class DACParamAddr(Enum):
     """
     EdgePi DAC Calibration Parameter Addresses
     Each parameter, gain and offset, are 4 bytes long 0x200~0x23F
     Ex) CH0_gain = 0x200~0x203, CH0_offset = 0x204~0x207
     """
-
     CH0 = 0x200
     CH1 = 0x208
     CH2 = 0x210
@@ -35,13 +37,12 @@ class DACParamAddr(Enum):
     CH6 = 0x230
     CH7 = 0x238
     LEN = 63
-
+# TODO: to be deleted once protobuf is implemented
 class ADCParamAddr(Enum):
     """
     EdgePi DAC Calibration Parameter Addresses
     Each parameter, gain and offset, are 4 bytes long
     """
-
     CH0 = 0x240
     CH1 = 0x248
     CH2 = 0x240
@@ -54,7 +55,7 @@ class ADCParamAddr(Enum):
     DIFF2 =0x258
     DIFF3 =0x260
     DIFF4 =0x268
-
+# TODO: to be deleted once protobuf is implemented
 class MemoryAddr(Enum):
     """
     Memory offset values
@@ -66,3 +67,82 @@ class MemoryAddr(Enum):
     RTD = 0x2C0
     END = 0x3FF
     CH_OFFSET = 0x8
+
+class EdgePiMemoryInfo(Enum):
+    """
+    Information regarding Edgepi reserved memory space
+    """
+    USED_SPACE = 0x00
+    BUFF_START = 0x02
+
+class MessageFieldNumber(Enum):
+    """
+    MessageField index number to be used for ListFields() function. The function lists fields start
+    from index 0
+    """
+    DAC=1
+    ADC=2
+    RTD=3
+    TC=4
+    CONFIGS_KEY=5
+    DATA_KEY=6
+    SERIAL=7
+    MODEL=8
+    CLIENT_ID=9
+
+@dataclass
+class Keys:
+    """
+    Dataclass to store key strings
+    """
+    certificate: str = None
+    private: str = None
+
+@dataclass
+class EdgePiEEPROMData:
+    # pylint: disable=too-many-instance-attributes
+    """
+    Dataclass to store edgepi reserved values
+    dac_list (list): list of calibration parameters
+    adc_list (list): list of calibration parameters
+    rtd_list (list): list of calibration parameters
+    tc_list (list): list of calibration parameters
+    config_key (Keys): dataclass
+    data_key (Keys): dataclass
+    serial (str)
+    model (str)
+    client_id (str)
+    """
+    dac_calib_parms: list = None
+    adc_calib_parms: list = None
+    rtd_calib_parms: list = None
+    tc_calib_parms: list = None
+    config_key: Keys = None
+    data_key: Keys = None
+    serial: str = None
+    model: str = None
+    client_id: str = None
+
+    def message_to_list(self, data_to_unpack: EepromLayout = None):
+        """
+        Function to unpack message to list
+        Args:
+            data_to_unpack: EepromLayout message modules
+        Returns:
+            calib_list: 1-D array
+        """
+        calib_list=[]
+        for ch in data_to_unpack.calibs:
+            calib_list.append(ch.gain)
+            calib_list.append(ch.offset)
+        return calib_list
+
+    def keys_to_str(self, data_to_unpack: EepromLayout = None):
+        """
+        Function to unpack message to string
+        Args:
+            data_to_unpack: EepromLayout message keys
+        Returns:
+            Keys (dataclass): keys values
+        """
+        return Keys(certificate = data_to_unpack.certificate, private = data_to_unpack.private_key)

src/edgepi/calibration/eeprom_mapping.proto

@@ -0,0 +1,24 @@
+syntax = "proto3";
+
+message EepromLayout{
+  message ModuleCalibParams{
+    message ChannelCalib {
+      optional float gain = 1;
+      optional float offset = 2;
+    }
+    repeated ChannelCalib calibs = 1;
+  }
+  message AwsKey{
+    string private_key = 1;
+    string certificate = 2;
+  }
+  ModuleCalibParams dac = 1;
+  ModuleCalibParams adc = 2;
+  ModuleCalibParams rtd = 3;
+  ModuleCalibParams tc = 4;
+  AwsKey config_key = 5;
+  AwsKey data_key =6;
+  string serial_number = 7;
+  string model = 8;
+  string client_id = 9;
+}