=============================================================================

   MOXA UPort Series Driver version 5.x Arm-based platform Porting Guide

   Date: 08-09-2021
   Copyright (C) 2021, MOXA Inc.
=============================================================================
Content

1. Introduction
2. Port to Moxa UC-Series - Arm Based Computer
   2.1 Build binaries on a general ARM platform
   2.2 Cross-compiler and the UPort series driver
   2.3 Moxa cross-compiling interactive script
   2.4 Manually build the UPort series driver with a cross-compiler
   2.5 Deploy cross-compiled binary to target
3. Porting to Raspberry Pi OS
4. Porting to the Yocto Project on Raspberry Pi
   4.1 Prerequisite
   4.2 Create a Moxa layer for the Yocto Project
   4.3 Install a Moxa Layer into the Yocto Project
   4.4 Deploy the Yocto image in Raspberry Pi
   4.5 Start the UPort driver in Raspberry Pi
   4.6 Troubleshooting

-----------------------------------------------------------------------------
1. Introduction

   This document is about porting Moxa UPort series driver to the specified
   Arm-based platform. The following knowledge is recommended before reading
   the instructions in this guide.

     - Linux Kernel Programming
     - ARM Platform Compiler
     - Yocto Project Document
     - MOXA UC-Series Manual
     - Raspberry Pi Manual

   Instructions in this guide use examples of porting on the Moxa UC-Series
   Arm platform and Raspberry Pi. You can apply the experience of porting
   UPort series driver to other platforms.
   
   The UPort series driver fully supports all modern-day Linux distributions
   running on x86 environments, and the driver core is also compatible with
   the Arm platform. This document will guide you on how to port the UPort 
   series driver core.
   
   However, some platform-dependent services, such as installer, are not
   available. You may refer to the platform’s documentation to fulfill the
   requirements.
   
-----------------------------------------------------------------------------
2. Porting to Moxa UC-Series - Arm-Based Computer

   2.1 Build binaries on a general ARM platform

       If your platform is powerful and consists of the necessary development
       tools, the driver can be built on the platform directly. You can refer
       to readme.txt of UPort series driver to understand the requirement.

       The step of building this driver in an ARM environment is the same as
       in x86 and x64 environment.

       UPort 1100 Series driver
       # tar zxvf [DRIVER NAME].tgz
       # cd mxu11x0
       # ./mxinstall

       UPort 1200/1400/1600 Series driver
       # tar zxvf [DRIVER NAME].tgz
       # cd mxuport
       # ./mxinstall

       UPort 2210/2410 Series driver
       # tar zxvf [DRIVER NAME].tgz
       # cd mxuport2000
       # ./mxinstall

   2.2 Cross-compiler and the UPort series driver

       +--------------------------------------------------------------------+
       | Note: To cross-compile on a x86 or x64 Linux host, the target ARM  |
       |       environment's kernel source package and cross compiler       |
       |       toolchain must be installed first.                           |
       +--------------------------------------------------------------------+

       After installing and configuring the kernel source package and
       toolchain, you need to compile all of the source code with the kernel
       source package and toolchain.

       In this example, we install the cross-compiler for the Moxa UC-Series
       ARM-based computer. You can refer to the product's manual for further
       detail.

       (1) Download the cross-compiler toolchain and the kernel source
           package webpage under the product page.

           $ git clone https://github.com/Moxa-Linux/am335x-linux-4.4

           You can use the following command to show the git tag list and 
           checkout to the tag of specific UC device and firmware version.

           Show the tag list.

           $ git tag

           Checkout to the specific tag.

           $ git checkout UC-2100_V1.7 <--- Replace the tag name, 
                                            UC-2100_V1.7, with the UC Series 
                                            that is being used.

       (2) Download the toolchain from the product's webpage. The toolchain,
           which is used by the UC Series, is arm-linux-gnueabihf. It is a
           script that will install the related packages. Execute the script
           and follow the steps to install the Linux cross-compiler tools.
           You will need the root privilege to install the toolchain and the
           kernel source.

           # sh arm-linux-gnueabihf_6.3_Build_amd64_<build_date>.sh

           If the script shows the notification message: "Please export these
           environment variables before using toolchain", enter the following
           script command:

           # export PATH=$PATH:/usr/local/arm-linux-gnueabihf-6.3/usr/bin

       (3) The kernel source, which is used by the UC Series, is
           am335x-linux-4.4. You need to configure these files before
           starting to cross-compile.

           Move the kernel source to /moxa/kernel and configure the kernel
           source.

           # mv am335x-linux-4.4 /moxa/kernel
           # cd /moxa/kernel
           # make uc2100_defconfig <--- Replace the uc2100 with the UC Series
                                        that is being used.
           # make modules_prepare

           After the abovementioned steps, please follow the processes as set
           out in Section 2.3, “Moxa cross-compiling interactive script,” and
           Section 2.4, “Manually build the UPort series driver with a
           cross-compiler,” to cross-compile Moxa's driver for the UC-Series
           platforms.

           The UPort series driver, which includes the driver modules, needs
           to be compiled. The files are listed as follows.

           (a) For UPort 1100 series:
               - mxu11x0.ko: Moxa UPort 1100 series USB device driver.

           (b) For UPort 1200/1400/1600 series:
               - mxuport.ko: Moxa UPort 1200/1400/1600 series USB device driver.

           (c) For UPort 2000 series:
               - mxuport2000.ko: Moxa UPort 2000 series USB device driver.

           If it is preferred to build these binaries with automatic script,
           please refer to Section 2.3, “Moxa cross-compiling interactive script.”
           If you find the build script troublesome, or you prefer to build these
           binaries manually, please refer to Section 2.4., “Manually build the
           UPort series driver with a cross-compiler.”
           
           If you have generated the necessary binaries, please refer to
           section 2.5 to deploy to the target platform.

   2.3 Moxa cross-compiling interactive script

       2.3.1 Introduction

       To simplify the processes above, Moxa has provided an interactive
       script, "mxcc", to cross-compile these drivers. You may execute
       ./mxcc in the UPort series driver source directory to cross-compile the
       MOXA driver.

       2.3.2 Cross-compiling interactive script for UPort 1100 series

             #./mxcc
             Enter target device architecture (ARCH) [arm]: 
             Enter cross-compile (CROSS_COMPILE) [arm-linux-gnueabihf-]: 
             Enter target device kernel source directory [/moxa/kernel]: 
             ******************************************
             mxu11x0 cross-compile is success.
             ******************************************
             ************************************************************************
             MOXA UPort 1100 series driver cross-compile finish.
             If cross compile is success, driver is outputted to output folder.
             ************************************************************************

             The binaries will now be generated and placed in the output directory
             under the /moxa/mxuport1100 folder.

       2.3.3 Cross-compiling interactive script for UPort 1200/1400/1600 series

             The steps are as follows:

             # ./mxcc
             Enter target device architecture (ARCH) [arm]: 
             Enter cross-compile (CROSS_COMPILE) [arm-linux-gnueabihf-]: 
             Enter target device kernel source directory [/moxa/kernel/]: 
             ******************************************
             mxuport cross-compile is success.
             ******************************************
             ************************************************************************
             MOXA UPort 1200/1400/1600 series driver cross-compile finish.
             If cross compile is success, driver is outputted to output folder.
             ************************************************************************

             The binaries will now be generated and placed in the output directory
             under the /moxa/mxuport folder.

       2.3.4 Cross-compiling interactive script for UPort 2000 series

             Enter target device architecture (ARCH) [arm]: 
             Enter cross-compile (CROSS_COMPILE) [arm-linux-gnueabihf-]: 
             Enter target device kernel source directory [/moxa/kernel/]: 
             ******************************************
             mxuport2000 cross-compile is success.
             ******************************************
             ************************************************************************
             MOXA UPort 2000 series driver cross-compile finish.
             If cross compile is success, driver is outputted to output folder.
             ************************************************************************

             The binaries will now be generated and placed in the output directory
             under the /moxa/mxuport2000 folder.

   2.4 Manually build the UPort series driver with a cross-compiler

       2.4.1 To cross-compile UPort 1100 series driver, user can find "Makefile"
             in the driver folder, then run it.

             # make ARCH=<ARCH> CROSS_COMPILE=<CROSS_COMPILE> KDIR=<KERNEL_SOURCE> KVER_MAJOR=<KERNEL_MAJOR> KVER_MINOR=<KERNEL_MINOR>

             <ARCH>: The target ARM environment device's CPU architecture.
                     For example, arm, arm64.

             <CROSS_COMPILE>: The cross-compile toolchain path. If the
                              toolchain is arm-linux-gnueabihf and you already
                              add the path of toolchain to environment variable,
                              you should enter "arm-linux-gnueabihf-" here.

             <KERNEL_SOURCE>: The directory of target kernel source.

             <KERNEL_MAJOR>: The target ARM system kernel source's kernel major
                             version. You can use the command
                             "make kernelversion" to get kernel source's major
                             version.

                             e.g.
                             # make kernelversion
                             4.4.0
                             |
                             +--- kernel major version

             <KERNEL_MINOR>: The target ARM system kernel source's kernel minor
                             version. You can use the command
                             "make kernelversion" to get kernel source's major
                             version.

                             e.g.
                             # make kernelversion
                             4.4.0
                               |
                               +--- kernel minor version

             The "make" command would be similar to the following example:

             # make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- KDIR=/moxa/kernel KVER_MAJOR=4 KVER_MINOR=4

             After using "make" command to cross-compile the drivers, the driver 
             files "mxu11x0.ko" can be found in the /moxa/mxuport1100/driver
             directory.

       2.4.2 To cross-compile UPort 1200/1400/1600 series driver, user can find
             "Makefile" in the driver/mxuport folder, then run it.

             (1) Build mxuport.ko.

                 Run the Makefile in the /moxa/mxuport/driver/mxuport folder.
                 # make ARCH=<ARCH> CROSS_COMPILE=<CROSS_COMPILE> KDIR=<KERNEL_SOURCE> KVER_MAJOR=<KERNEL_MAJOR> KVER_MINOR=<KERNEL_MINOR>

                 <ARCH>: The target ARM environment device's CPU architecture.
                         For example, arm, arm64.

                 <CROSS_COMPILE>: The cross-compile toolchain path. If the
                                  toolchain is arm-linux-gnueabihf and you already
                                  add the path of toolchain to environment variable,
                                  you should enter "arm-linux-gnueabihf-" here.

                 <KERNEL_SOURCE>: The directory of target kernel source.

                 <KERNEL_MAJOR>: The target ARM system kernel source's kernel major
                                 version. You can use the command
                                 "make kernelversion" to get kernel source's major
                                 version.

                                 e.g.
                                 # make kernelversion
                                 4.4.0
                                 |
                                 +--- kernel major version

                 <KERNEL_MINOR>: The target ARM system kernel source's kernel minor
                                 version. You can use the command
                                 "make kernelversion" to get kernel source's major
                                 version.

                                 e.g.
                                 # make kernelversion
                                 4.4.0
                                   |
                                   +--- kernel minor version

                 The "make" command would be similar to the following example:

                 # make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- KDIR=/moxa/kernel KVER_MAJOR=4 KVER_MINOR=4

                 After using "make" command to cross-compile the drivers, the driver 
                 files "mxuport.ko" can be found in the /moxa/mxuport/driver/mxuport
                 directory.

       2.4.3 To cross-compile UPort 2000 series driver, user can find "Makefile"
             in the driver folder, then run it.


             # make ARCH=<ARCH> CROSS_COMPILE=<CROSS_COMPILE> KDIR=<KERNEL_SOURCE> KVER_MAJOR=<KERNEL_MAJOR> KVER_MINOR=<KERNEL_MINOR>

             <ARCH>: The target ARM environment device's CPU architecture.
                     For example, arm, arm64.

             <CROSS_COMPILE>: The cross-compile toolchain path. If the
                              toolchain is arm-linux-gnueabihf and you already
                              add the path of toolchain to environment variable,
                              you should enter "arm-linux-gnueabihf-" here.

             <KERNEL_SOURCE>: The directory of target kernel source.

             <KERNEL_MAJOR>: The target ARM system kernel source's kernel major
                             version. You can use the command
                             "make kernelversion" to get kernel source's major
                             version.

                             e.g.
                             # make kernelversion
                             4.4.0
                             |
                             +--- kernel major version

             <KERNEL_MINOR>: The target ARM system kernel source's kernel minor
                             version. You can use the command
                             "make kernelversion" to get kernel source's major
                             version.

                             e.g.
                             # make kernelversion
                             4.4.0
                               |
                               +--- kernel minor version

             The "make" command would be similar to the following example:

             # make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- KDIR=/moxa/kernel KVER_MAJOR=4 KVER_MINOR=4

             After using "make" command to cross-compile the drivers, the driver 
             files "mxuport2000.ko" can be found in the /moxa/mxuport2000/driver
             directory.

       2.4.4 To cross-compile UPort 2000 series driver's utility, you can follow
             the below steps.

             You can find the source in the utility folder.

             # cd /moxa/mxuport2000/utility/conftool/

             Use cross compiler to compile the utility.

             # <CROSS_COMPILE>gcc -o mxustty conftool.c

             After using cross compiler  to compile the utility, you can find the
             utility execution 'mxustty' in /moxa/mxuport2000/utility/conftool/

   2.5 Deploy cross-compiled binary to target

       2.5.1 For UPort 1100 series

             You should find the kernel module, mxu11x0.ko, under the output or 
             driver source code directory.

             Follow the steps below to deploy to the target Arm platform.

             (1) Copy the mxuport.ko and mxusbserial.ko to the path 
                 /lib/modules/`uname -r`/kernel/drivers/char on the ARM platform.

             (2) Boot into the ARM platform and load the driver.

                 # modprobe mxu11x0


       2.5.2 For UPort 1200/1400/1600 series

             You should find the kernel module, mxuport.ko, under the output or 
             driver source code directory.

             Follow the steps below to deploy to the target Arm platform.

             (1) Copy the mxuport.ko to the path 
                 /lib/modules/`uname -r`/kernel/drivers/char on the ARM platform.

             (2) Boot into the ARM platform and load the driver.

                 # modprobe mxuport


       2.5.3 For UPort 2000 series

             You should find the kernel module, mxuport2000.ko, under the output
             or driver source code directory.

             Follow the steps below to deploy to the target Arm platform.

             (1) Copy the mxuport.ko and mxusbserial.ko to the path 
                 /lib/modules/`uname -r`/kernel/drivers/char on the ARM platform.

             (2) Boot into the ARM platform and load the driver.

                 # modprobe mxuport2000


-----------------------------------------------------------------------------

3. Porting to Raspberry Pi OS

   Raspberry Pi OS images are prebuilt by www.raspberrypi.org. You can
   install the image and start up the system. The process to build the UPort
   series driver is the same as with x86 Linux. Please refer to readme.txt to
   check the system requirements.

   You may use the rpi-source to install the kernel source packages for a
   more convenient option. Please refer to the official website
   https://github.com/notro/rpi-source/wiki for more information.

   rpi-source is a third-party package offering an integrated kernel resource
   for building a driver. The UPort series is tested with this package to see if
   it works well. However, the requirements may vary for different Raspberry
   Pi OS versions. Please read the manual of rpi-source to understand the 
   know-how and the limitations.


-----------------------------------------------------------------------------
4. Porting to the Yocto Project on Raspberry Pi 

   4.1 Prerequisite

       You are expected to be familiar with the Yocto Project. Please refer
       to https://docs.yoctoproject.org for the Yocto Project documentation
       for further understanding. Also, it is encouraged to follow the
       procedures in this guide unless you have sufficient knowledge about
       the UPort series driver, the Yocto Project, and Raspberry Pi.

       The dunfell branch (3.1.9) is referred to throughout in this section.
       Please base it on this version before reading the instructions in the
       Yocto Project documentation. You are required to build the Yocto image
       successfully with the "Yocto Project Quick Build" document.

       In Yocto Project, you can select the platform you want to build. This
       guild installs Raspberry Pi BSP Layer as a demonstration in the
       following steps:

       (1) Suppose the Yocto is installed in /home/user/poky folder. Checkout
           the source code of the Raspberry Pi BSP Layer.

           # cd /home/user/poky
           # git clone https://git.yoctoproject.org/cgit/cgit.cgi/meta-raspberrypi -b dunfell

       (2) A meta-raspberrypi folder will be checked out now. Use the
           following instructions to set up Raspberry Pi BSP:

           # source oe-init-build-env

       (3) Use a text editor to add the following content to the
           configuration file './conf/local.conf'.

       (4) Add the type 'rpi-sdimg' optionally if SD card is preferred 

           IMAGE_FSTYPES="tar.bz2 ext3 rpi-sdimg"

       (5) Change the machine name of your target
           Use raspberrypi2 for Pi 2 board
           Use raspberrypi3 for Pi 3 board
           Use raspberrypi3-64 for 64-bit Pi 3 board

           MACHINE ?= "raspberrypi2"

       (6) Use the text editor to add the following content to the
           configuration file './conf/bblayers.conf'

       (7) Add this line '/home/user/poky/meta-raspberrypi' to BBLAYERS

           BBLAYERS ?= " \
           /home/user/poky/meta \
           /home/user/poky/meta-poky \
           /home/user/poky/meta-yocto-bsp \
           /home/user/poky/meta-raspberrypi \
           " 

       (8) Build the target core-image-base by following this command and the
           Raspberry Pi image will be generated:

           # bitbake core-image-base

       Once the above image runs on Raspberry Pi, go to the next section.


   4.2 Create a Moxa layer for the Yocto Project

       4.2.1 Introduction

             Moxa UPort series driver is packaged as a layer for Yocto.
             User can add or remove the driver by modifying BBLAYERS attribute 
             in the bblayers.conf file.

             The following sections describe how to create meta-moxa layer
             for the dunfell branch (3.1.9). Note that process may vary if
             your target uses a different branch. Please refer Yocto's manual
             for complete information.

             An example is also available in the examples folder in the UPort
             series driver.

             You may follow the subsequent procedures to create the same
             meta-moxa layer.

       4.2.2 Create an empty Moxa Layer

             Use the following commands to create an empty layer, named
             meta-moxa.

             (1) Initiate the environment first. Suppose the project is
                 installed in /home/user/poky.

                 $ cd /home/user/poky
                 $ source oe-init-build-env

             (2) The above commands changed the directory to the built
                 directory. Now, we change the directory back to the Yocto
                 root directory.

                $ cd /home/user/poky

             (3) Create meta-moxa:
                 A message is appears reminding you to add the layer later.

                 $ bitbake-layers create-layer meta-moxa
                 NOTE: Starting bitbake server...
                 Add your new layer with 'bitbake-layers add-layer meta-moxa'

                 The meta-moxa directory will be created in /home/user/poky:

                 $ tree meta-moxa
                 meta-moxa
                 ├── conf
                 │   └── layer.conf
                 ├── COPYING.MIT
                 ├── README
                 └── recipes-example
                     └── example
                         └── example_0.1.bb

                 The “recipes-example” folder is not necessary; it may be
                 deleted at anytime.

       4.2.3 Create a Recipe for the UPort driver

             Use the following commands to create a recipe for installing
             UPort driver kernel to the target platform.

             (1) Create a directory recipes-kernel in meta-moxa:

                 $ cd /home/user/poky
                 $ mkdir meta-moxa/recipes-kernel

             (2) The simplest way is to copy and modify from a hello example,
                 which is available in the Yocto source code:

                 $ cp -r ./meta-skeleton/recipes-kernel/hello-mod ./meta-moxa/recipes-kernel

                 The content of meta-moxa now is listed below:

                 $ tree meta-moxa
                 meta-moxa/
                 ├── conf
                 │   └── layer.conf
                 ├── COPYING.MIT
                 ├── README
                 └── recipes-kernel
                     └── hello-mod
                         ├── files
                         │   ├── COPYING
                         │   ├── hello.c
                         │   └── Makefile
                         └── hello-mod_0.1.bb

             (3) Delete the unnecessary files in hello-mod. Rename the
                 hello-mod.

                 (a) For UPort 1100 series:
                     $ cd ./meta-moxa/recipes-kernel
                     $ rm ./hello-mod/files/COPYING
                     $ rm ./hello-mod/files/hello.c
                     $ mv ./hello-mod/hello-mod_0.1.bb ./hello-mod/uport1100_0.1.bb
                     $ mv ./hello-mod uport1100

                 (b) For UPort 1200/1400/1600 series:

                       $ cd ./meta-moxa/recipes-kernel
                       $ rm ./hello-mod/files/COPYING
                       $ rm ./hello-mod/files/hello.c
                       $ mv ./hello-mod/hello-mod_0.1.bb ./hello-mod/mxuport_0.1.bb
                       $ mv ./hello-mod mxuport

                 (c) For UPort 2000 series:
                     $ cd ./meta-moxa/recipes-kernel
                     $ rm ./hello-mod/files/COPYING
                     $ rm ./hello-mod/files/hello.c
                     $ mv ./hello-mod/hello-mod_0.1.bb ./hello-mod/uport2000_0.1.bb
                     $ mv ./hello-mod uport2000

             (4) Extract the UPort driver source code. Copy the following 
                 files into hello-mod:

                 (a) For UPort 1100 series:

                     $ cp /moxa/mxuport1100/COPYING-GPLV2.TXT ./uport1100/files/
                     $ cp /moxa/mxuport1100/driver/mxu11x0.c ./uport1100/files/
                     $ cp /moxa/mxuport1100/driver/mxu11x0.h ./uport1100/files/
                     $ cp /moxa/mxuport1100/driver/mxu1110_fw.h ./uport1100/files/
                     $ cp /moxa/mxuport1100/driver/mxu1130_fw.h ./uport1100/files/
                     $ cp /moxa/mxuport1100/driver/mxu1131_fw.h ./uport1100/files/
                     $ cp /moxa/mxuport1100/driver/mxu1150_fw.h ./uport1100/files/
                     $ cp /moxa/mxuport1100/driver/mxu1151_fw.h ./uport1100/files/
                     $ cp /moxa/mxuport1100/driver/mxu3001_fw.h ./uport1100/files/
                     $ cp /moxa/mxuport1100/driver/usb-serial.h ./uport1100/files/
                     $ cp /moxa/mxuport1100/driver/mx_ver.h ./uport1100/files/

                 (b) For UPort 1200/1400/1600 series:

                       $ cp /moxa/mxuport/COPYING-GPLV2.TXT ./mxuport/files/
                       $ cp /moxa/mxuport/driver/mxuport/mx-uport.c ./mxuport/files/
                       $ cp /moxa/mxuport/driver/mxuport/mx-uport.h ./mxuport/files/
                       $ cp /moxa/mxuport/driver/mxuport/UPort1250FW.h ./mxuport/files/
                       $ cp /moxa/mxuport/driver/mxuport/UPort1250IFW.h ./mxuport/files/
                       $ cp /moxa/mxuport/driver/mxuport/UPort1410FW.h ./mxuport/files/
                       $ cp /moxa/mxuport/driver/mxuport/UPort1450FW.h ./mxuport/files/
                       $ cp /moxa/mxuport/driver/mxuport/UPort1450IFW.h ./mxuport/files/
                       $ cp /moxa/mxuport/driver/mxuport/UPort1610_16FW.h ./mxuport/files/
                       $ cp /moxa/mxuport/driver/mxuport/UPort1610_8FW.h ./mxuport/files/
                       $ cp /moxa/mxuport/driver/mxuport/UPort1650_16FW.h ./mxuport/files/
                       $ cp /moxa/mxuport/driver/mxuport/UPort1650_8FW.h ./mxuport/files/
                       $ cp /moxa/mxuport/driver/mxuport/mx_ver.h ./mxuport/files/

                 (c) For UPort 2000 series:

                     $ cp /moxa/mxuport2000/COPYING-GPLV2.TXT ./uport2000/files/
                     $ cp /moxa/mxuport2000/driver/mxuport2000.c ./uport2000/files/
                     $ cp /moxa/mxuport2000/driver/mxuport2000.h ./uport2000/files/
                     $ cp /moxa/mxuport2000/driver/mx_ver.h ./uport2000/files/

             (5) The content of the recipes-kernel now is listed below:

                 (a) For UPort 1100 series:

                     $ tree ./
                     ./
                     └── uport1100
                         ├── files
                         │   ├── COPYING-GPLV2.TXT
                         │   ├── Makefile
                         │   ├── mxu1110_fw.h
                         │   ├── mxu1130_fw.h
                         │   ├── mxu1131_fw.h
                         │   ├── mxu1150_fw.h
                         │   ├── mxu1151_fw.h
                         │   ├── mxu11x0.c
                         │   ├── mxu11x0.h
                         │   ├── mxu3001_fw.h
                         │   ├── mx_ver.h
                         │   └── usb-serial.h
                         └── uport1100_0.1.bb

                 (b) For UPort 1200/1400/1600 series:

                       $ tree ./
                       ./
                       └── mxuport
                           ├── files
                           │   ├── COPYING-GPLV2.TXT
                           │   ├── Makefile
                           │   ├── mx-uport.c
                           │   ├── mx-uport.h
                           │   ├── mx_ver.h
                           │   ├── UPort1250FW.h
                           │   ├── UPort1250IFW.h
                           │   ├── UPort1410FW.h
                           │   ├── UPort1450FW.h
                           │   ├── UPort1450IFW.h
                           │   ├── UPort1610_16FW.h
                           │   ├── UPort1610_8FW.h
                           │   ├── UPort1650_16FW.h
                           │   └── UPort1650_8FW.h
                           └── mxuport_0.1.bb

                 (c) For UPort 2000 series:

                     $ tree ./
                     ./
                     └── uport2000
                         ├── files
                         │   ├── COPYING-GPLV2.TXT
                         │   ├── Makefile
                         │   ├── mxuport2000.c
                         │   ├── mxuport2000.h
                         │   └── mx_ver.h
                         └── uport2000_0.1.bb

             (6) Modify the content of the files 'Makefile' in the files folder
                 as follows:

                 (a) For UPort 1100 series:

                     ##### Makefile start #####

                     obj-m := mxu11x0.o
                     
                     SRC := $(shell pwd)
                     
                     all:
                         $(MAKE) -C $(KERNEL_SRC) M=$(SRC)
                     
                     modules_install:
                         $(MAKE) -C $(KERNEL_SRC) M=$(SRC) modules_install
                     
                     clean:
                         rm -f *.o *~ core .depend .*.cmd *.ko *.mod.c
                         rm -f Module.markers Module.symvers modules.order
                         rm -rf .tmp_versions Modules.symvers

                     ##### Makefile end #####

                 (b) For UPort 1200/1400/1600 series:

                       ##### Makefile start #####

                       obj-m := mxuport.o
                       mxuport-objs := mx-uport.o
                       
                       SRC := $(shell pwd)
                       
                       all:
                           $(MAKE) -C $(KERNEL_SRC) M=$(SRC)
                       
                       modules_install:
                           $(MAKE) -C $(KERNEL_SRC) M=$(SRC) modules_install
                       
                       clean:
                           rm -f *.o *~ core .depend .*.cmd *.ko *.mod.c
                           rm -f Module.markers Module.symvers modules.order
                           rm -rf .tmp_versions Modules.symvers

                       ##### Makefile end #####

                 (c) For UPort 2000 series:

                     ##### Makefile start #####

                     obj-m := mxuport2000.o
                     
                     SRC := $(shell pwd)
                     
                     all:
                         $(MAKE) -C $(KERNEL_SRC) M=$(SRC)
                     
                     modules_install:
                         $(MAKE) -C $(KERNEL_SRC) M=$(SRC) modules_install
                     
                     clean:
                         rm -f *.o *~ core .depend .*.cmd *.ko *.mod.c
                         rm -f Module.markers Module.symvers modules.order
                         rm -rf .tmp_versions Modules.symvers

                     ##### Makefile end #####

             (7) Modify the content of the file '*_0.1.bb'
                 as follows:

                 (a) For UPort 1100 series:

                     We have to Modify the content of the file 'uport1100_0.1.bb'.

                     ##### uport1100_0.1.bb start #####

                     DESCRIPTION = "Linux kernel module for Moxa UPort 11x0 series"
                     LICENSE = "GPLv2"
                     LIC_FILES_CHKSUM = "file://COPYING-GPLV2.TXT;md5=5205bcd21ef6900c98e19cf948c26b41"
                     
                     inherit module
                     
                     SRC_URI = "file://Makefile \
                                file://mxu1110_fw.h \
                                file://mxu1130_fw.h \
                                file://mxu1131_fw.h \
                                file://mxu1150_fw.h \
                                file://mxu1151_fw.h \
                                file://mxu11x0.h \
                                file://mxu3001_fw.h \
                                file://mx_ver.h \
                                file://usb-serial.h \
                                file://mxu11x0.c \
                                file://COPYING-GPLV2.TXT \
                               "
                     
                     S = "${WORKDIR}"
                     
                     # The inherit of module.bbclass will automatically name module packages with
                     # "kernel-module-" prefix as required by the oe-core build environment.
                     
                     RPROVIDES_${PN} += "kernel-module-mxu11x0"

                     ##### uport1100_0.1.bb end #####

                 (b) For UPort 1200/1400/1600 series:

                       We have to Modify the content of the file 'mxuport_0.1.bb'.

                       ##### mxuport_0.1.bb start #####

                       DESCRIPTION = "Linux kernel module for Moxa UPort 1200/1400/1600 series"
                       LICENSE = "GPLv2"
                       LIC_FILES_CHKSUM = "file://COPYING-GPLV2.TXT;md5=5205bcd21ef6900c98e19cf948c26b41"
                       
                       inherit module
                       
                       SRC_URI = "file://Makefile \
                                  file://mx-uport.c \
                                  file://mx-uport.h \
                                  file://mx_ver.h \
                                  file://UPort1250FW.h \
                                  file://UPort1250IFW.h \
                                  file://UPort1410FW.h \
                                  file://UPort1450FW.h \
                                  file://UPort1450IFW.h \
                                  file://UPort1610_16FW.h \
                                  file://UPort1610_8FW.h \
                                  file://UPort1650_16FW.h \
                                  file://UPort1650_8FW.h \
                                  file://COPYING-GPLV2.TXT \
                                 "
                       
                       S = "${WORKDIR}"
                       
                       # The inherit of module.bbclass will automatically name module packages with
                       # "kernel-module-" prefix as required by the oe-core build environment.
                       
                       RPROVIDES_${PN} += "kernel-module-mxuport"

                       ##### mxuport_0.1.bb end #####

                 (c) For UPort 2000 series:

                     We have to Modify the content of the file 'uport2000_0.1.bb'.

                     ##### uport2000_0.1.bb start #####

                     DESCRIPTION = "Linux kernel module for Moxa UPort 2000 series"
                     LICENSE = "GPLv2"
                     LIC_FILES_CHKSUM = "file://COPYING-GPLV2.TXT;md5=5205bcd21ef6900c98e19cf948c26b41"
                     
                     inherit module
                     
                     SRC_URI = "file://Makefile \
                                file://mxuport2000.h \
                                file://mx_ver.h \
                                file://mxuport2000.c \
                                file://COPYING-GPLV2.TXT \
                               "
                     
                     S = "${WORKDIR}"
                     
                     # The inherit of module.bbclass will automatically name module packages with
                     # "kernel-module-" prefix as required by the oe-core build environment.
                     
                     RPROVIDES_${PN} += "kernel-module-uport2000"

                     ##### uport2000_0.1.bb end #####

       4.2.4 Create a Recipe for the UPort driver utilities

             If you are using UPort 2000 series driver. It contained a utility.
             Similar to creating a uport2000-kernel recipe, create a recipe for
             facilitating the UPort 2000 driver's utility.

             (1) Create directory below in meta-moxa:

                 $ cd /home/user/poky
                 $ mkdir -p ./meta-moxa/recipes-utility/uport2000-tools/files

             (2) Copy the utility source code from UPort 2000 driver utilty 
                 folder.

                 $ cp /moxa/mxuport2000/COPYING-GPLV2.TXT ./meta-moxa/recipes-utility/uport2000-tools/files/
                 $ cp /moxa/mxuport2000/utility/conftool/conftool.c ./meta-moxa/recipes-utility/uport2000-tools/files/

             (3) Create a bb file ./meta-moxa/recipes-utility/uport2000-tools/uport2000-tools.bb
                 which has the following content:

                 ##### uport2000-tools.bb start #####
                 
                 DESCRIPTION = "Utilities for UPort 2000 series"
                 LICENSE = "GPLv2"
                 LIC_FILES_CHKSUM = "file://COPYING-GPLV2.TXT;md5=5205bcd21ef6900c98e19cf948c26b41"
                 
                 SRC_URI = " \
                         file://conftool.c \
                         file://COPYING-GPLV2.TXT \
                 "
                 
                 S = "${WORKDIR}"
                 DEST_DIR = "${D}${libdir}/mxuport2000/driver"
                 
                 FILES_${PN} += "${libdir}/mxuport2000/driver/*"
                 
                 do_compile () {
                         ${CC} -o mxustty conftool.c
                 }
                 
                 do_install () {
                         install -m 0755 -d ${DEST_DIR}
                         install -m 0755 ${S}/mxustty ${DEST_DIR}
                         cp ${S}/mxustty ${DEST_DIR}/mxustty
                 }
                 
                 INSANE_SKIP_${PN} = "ldflags"
                 
                 ##### uport2000-tools.bb end #####

                (4) The content of recipes-utility is listed below:

                    $ tree recipes-utility
                    recipes-utility
                    └── uport2000-tools
                        ├── files
                        │   ├── conftool.c
                        │   └── COPYING-GPLV2.TXT
                        └── uport2000-tools.bb


   4.3 Install a Moxa Layer into the Yocto Project

       (1) Install the Moxa layer and UPort driver recipes into the Yocto Project.

           $ cd /home/user/poky
           $ source oe-init-build-env


       (2) Use a text editor to add the following content to the configuration
           file: './conf/bblayers.conf'

       (3) Add this line '/home/user/poky/meta-moxa' to BBLAYERS

           BBLAYERS ?= " \
           /home/user/poky/meta \
           /home/user/poky/meta-poky \
           /home/user/poky/meta-yocto-bsp \
           /home/user/poky/meta-raspberrypi \
           /home/user/poky/meta-moxa \
           "

       (4) Use a text editor to add the following content to the configuration
           file: './conf/local.conf'.

           (a) For UPort 1100 series:
               IMAGE_INSTALL_append += " uport1100"

           (b) For UPort 1200/1400/1600 series:
               IMAGE_INSTALL_append += " mxuport"

           (c) For UPort 2000 series:
               IMAGE_INSTALL_append += " uport2000 uport2000-tools"


   4.4 Deploy the Yocto image in Raspberry Pi

       Build the image with UPort driver:

       $ cd /home/user/poky
       $ source oe-init-build-env
       $ bitbake core-image-base

       An SD-card format image (.rpi-sdimg) is generated under
       /home/user/poky/build/tmp/deploy/images/raspberrypi2. It is suggested
       to use the Raspberry Pi official tool 'rpi-imager' to burn the image
       into the SD-card and then boot it into the Linux kernel in Raspberry Pi.


   4.5 Start the UPort driver in Raspberry Pi

       After logging into the system, start the UPort driver

       (a) For UPort 1100 series:

           root@raspberrypi2:~# modprobe mxu11x0

       (b) For UPort 1200/1400/1600 series:

           root@raspberrypi2:~# modprobe mxuport

       (c) For UPort 2000 series:

           Start UPort 2000 series driver.

           root@raspberrypi2:~# modprobe mxuport2000

           Use mxustty to locate ttyUSB0.

           root@raspberrypi2:~# cd /usr/lib/mxuport2000/driver
           root@raspberrypi2:~# ./mxustty -l /dev/ttyUSB0
           mxustty: Open device /dev/ttyUSB0 ok.
           mxustty: Locating device...
           mxustty: Press Enter to Stop the Buzzer or LED...

   4.6 Troubleshooting

       If the following error is encountered during the building of the image,

       ERROR: Task (/home/user/poky/meta/recipes-devtools/binutils/binutils_2.34.bb:do_compile) failed with exit code '1'

       It is suggested to compile binutils first, then compile the entire image:

       $ bitbake binutils -c do_compile
       $ bitbake core-image-base

