DART-MX8M Android Modem

DART-MX8M - Android O8.1.0_1.3.0 - mPCIE - Modem

Overview

The DART-MX8M is capable of adding a Mini PCI-E based modem to support LTE connectivity.

Note:

• At present we support LTE Quectel EC25.
• Other modules could be supported please contact your module vendor.
• Below steps are validated and tested upto Android 11 version.

Hardware Interface

• Quectel EC25 mPCI-E Hardware module with a SIM card.
  
• mPCI-E interface with USB support, like the one on the DT8MCustomBoard (note that the Symphony-Board mPCI-E interface does not support USB).

Hardware Availability and Setup

• Connect SIM card to mPCIe-E module.
• Connect mPCI-E Module to J23.

Note: Make sure your SIM provider is supporting mPCI-E module specification of the network.

Software Setup

Make sure you have the required hardware as per above.

RIL Setup

By default, the build doesn't have a RIL setup.
To add the RIL support follow the below steps.

Register and get access to the download zone https://www.quectel.com/login
Download Quectel_Android_RIL_Driver_XX.Y.ZZ_master_<release>.tgz
Where (XX.Y.ZZ are version numbers from quectel and <release> can be alpha/beta etc)

Adding Driver to build

Edit imx8m_var_dart_android_defconfig and enable following

Device Drivers->
 Network device support ->
  USB Network Adapters ->
   Multi-purpose USB Networking Framework ->
    <*> QMI WWAN driver for Qualcomm MSM based 3G and LTE modems

and enable

CONFIG_USB_NET_QMI_WWAN=y

Downloading and adding Quectel RIL to build

$ cd ~/var_imx-o8.1.0_1.3.0_8m/android_build
$ mkdir -p vendor/quectel/
$ tar -xvf ~/Downloads/Quectel_Android_RIL_Driver_V3.3.49_master_beta.tgz -C vendor/quectel/

Add Quectel libraries to build

Edit device/variscite/imx8m/dart_mx8m/dart_mx8m.mk and add following code

TARGET_HAVE_QUECTEL_RIL := true 
ifeq ($(TARGET_HAVE_QUECTEL_RIL),true)
# wifionly device
PRODUCT_PROPERTY_OVERRIDES += \
    ro.radio.noril=false

PRODUCT_COPY_FILES += \
	vendor/quectel/libquectel-ril/arm64-v8a/libreference-ril.so:vendor/lib64/hw/libreferece-ril.so \
	vendor/quectel/libquectel-ril/arm64-v8a/ip-up:vendor/bin/ip-up \ 
	vendor/quectel/libquectel-ril/arm64-v8a/chat:vendor/bin/chat \
	vendor/quectel/libquectel-ril/arm64-v8a/ip-down:vendor/bin/ip-down \
	vendor/quectel/libquectel-ril/ql-ril.conf:vendor/etc/ql-ril.conf
fi

Add Quectel libraries in the ril-daemon service

Edit device/variscite/imx8m/dart_mx8m/init.rc and add following code

service ril-daemon /vendor/bin/hw/rild -l vendor/lib64/hw/
    class main
    user radio
    group radio cache inet misc audio sdcard_rw log
    capabilities BLOCK_SUSPEND NET_ADMIN NET_RAW

Add RILD in the HIDL service

Edit device/variscite/imx8m/dart_mx8m/manifest.xml and add following code

<hal format="hidl">
	<name>android.hardware.radio</name>
	<transport>hwbinder</transport>
	<fqname>@1.4::IRadio/slot1</fqname>
	<fqname>@1.2::ISap/slot1</fqname>
</hal>

Setup file context and selinux permissions

Edit device/variscite/imx8m/dart_mx8m/ueventd.nxp.rc and add following code

#quectel port
/dev/ttyUSB* 0660 radio radio
/dev/ttyACM* 0660 radio radio
/dev/cdc-wdm* 0660 radio radio
/dev/qcqmi* 0660 radio radio
/dev/cdc-acm* 0660 radio radio
#PCIe
/dev/mhi_DUN 0660 radio radio
/dev/mhi_DIAG 0660 radio radio
/dev/mhi_BHI 0660 radio radio
/dev/mhi_LOOPBACK 0660 radio radio
/dev/mhi_QMI0 0660 radio radio

Edit device/variscite/imx8m/dart_mx8m/sepolicy/file_contexts and add following code

#quectel
/dev/ttyUSB[0-9] u:object_r:radio_device:s0
/dev/ttyACM[0-9] u:object_r:radio_device:s0
/dev/cdc-wdm[0-9] u:object_r:radio_device:s0
/dev/qcqmi[0-9] u:object_r:radio_device:s0
/vendor/bin/hw/rild u:object_r:rild_exec:s0
/dev/socket/rildOemHook u:object_r:rild_socket:s0
#PCIe
/dev/mhi_DUN u:object_r:radio_device:s0
/dev/mhi_DIAG u:object_r:radio_device:s0
/dev/mhi_BHI u:object_r:radio_device:s0
/dev/mhi_LOOPBACK u:object_r:radio_device:s0
/dev/mhi_QMI0 u:object_r:radio_device:s0

Create a seplicy file for rild to allow the socket communication File : device/variscite/imx8m/dart_mx8m/sepolicy/rild.te and add the following content to it.

allow rild self:packet_socket { create bind write read };

Build Android Images with RIL

Rebuild the android images using
Developers Guide

Flash Android Images with RIL

Flash the resulting Android Images Developers Guide

References

1. https://forums.quectel.com/uploads/short-url/paFeIdgzFeu3ArLuJEfWpWkIV05.pdf
2. https://www.quectel.com/product/lte-ec25-mini-pcie-series