RK3568系列21——移远4G模块配置

　　拿到手的4G模块是移远的EC200系列，具体型号是EC200N-CN，这个系列和网上流传比较多的EC20系列有所不同，EC20系列一般使用wwan驱动，正确驱动后系统会生成wwan0网卡，而EC200系列走的是ECM驱动，正确驱动后系统生成的是usb0网卡。除了驱动部分，其他步骤基本相似，也有一定参考价值。另外调试模块最好要先跟原厂取得联系，拿到文档和驱动，有技术支持就更好了。

DTS配置

　　首先需要一个简单的驱动，来操作上电步骤，让4G模块工作起来，RK提供了一个现成的驱动，代码位于kernel/drivers/net/lte/lte_rm310.c，这里我们直接在DTS中使用这个驱动。正常来讲reset脚一般是低有效，但是我们经过了一个三极管产生了反向，因此变成了高有效，另外power脚根据原理图可以不接，因此这边直接注释掉。

rk_modem: rk-modem {
    status = "okay";
    compatible = "4g-modem-platdata";
    4G,vbat-gpio = <&gpio4 RK_PB2 GPIO_ACTIVE_HIGH>;
    // 4G,power-gpio = <&gpio4 RK_PC6 GPIO_ACTIVE_LOW>;
    4G,reset-gpio = <&gpio4 RK_PB3 GPIO_ACTIVE_HIGH>;
    pinctrl-names = "default";
    pinctrl-0 = <&lte_power &lte_reset>;
};

&pinctrl {
    4g-lte {
        lte_power: lte-power {
            rockchip,pins = <4 RK_PB2 RK_FUNC_GPIO &pcfg_pull_down>;
        };
        lte_reset: lte-reset {
            rockchip,pins = <4 RK_PB3 RK_FUNC_GPIO &pcfg_pull_up>;
        };
    };
};

　　另外原始的驱动是针对RK自己的RM310模块，这里参考移远的《Quectel_EC200N-CN_硬件设计手册_V1.1》修改了一下驱动的上电顺序。

diff kernel/drivers/net/lte/lte_rm310.c
@@ -44,17 +44,17 @@ static int modem_poweron_off(int on_off)
        if (pdata) {
                if (on_off) {
                        LOG("%s: 4g modem power up.\n", __func__);
-                       if (pdata->vbat_gpio) {
+                       // for Quectel EC200N
+                       if (pdata->vbat_gpio)
                                gpiod_direction_output(pdata->vbat_gpio, 1);
-                               msleep(2000);
-                       }
-                       if (pdata->power_gpio) {
-                               gpiod_direction_output(pdata->power_gpio, 0);
-                               msleep(50);
+                       if (pdata->power_gpio)
                                gpiod_direction_output(pdata->power_gpio, 1);
-                               msleep(400);
-                               gpiod_direction_output(pdata->power_gpio, 0);
-                       }
+                       msleep(200);
+                       if (pdata->reset_gpio)
+                               gpiod_direction_output(pdata->reset_gpio, 1);
+                       msleep(400);
+                       if (pdata->reset_gpio)
+                               gpiod_direction_output(pdata->reset_gpio, 0);
                } else {
                        LOG("%s: 4g modem power down.\n", __func__);
                        if (pdata->power_gpio) {
@@ -118,14 +118,14 @@ static int modem_platdata_parse_dt(struct device *dev,
        memset(data, 0, sizeof(*data));
        LOG("%s: LTE modem power controlled by gpio.\n", __func__);
        data->vbat_gpio = devm_gpiod_get_optional(dev, "4G,vbat",
-                                                 GPIOD_OUT_HIGH);
+                                                 GPIOD_OUT_LOW);
        if (IS_ERR(data->vbat_gpio)) {
                ret = PTR_ERR(data->vbat_gpio);
                dev_err(dev, "failed to request 4G,vbat GPIO: %d\n", ret);
                return ret;
        }
        data->power_gpio = devm_gpiod_get_optional(dev, "4G,power",
-                                                  GPIOD_OUT_HIGH);
+                                                  GPIOD_OUT_LOW);
        if (IS_ERR(data->power_gpio)) {
                ret = PTR_ERR(data->power_gpio);
                dev_err(dev, "failed to request 4G,power GPIO: %d\n", ret);

　　这两步完成后编译刷机上电，正确的话应该能在dmesg日志中认到这个4G模块，其VendorId不论什么型号，只要是移远的应该均为0x2c7c，例如如下显示。由于4G模块步骤较多，建议一步一步的完成，方便排查问题出在哪个阶段。

# dmesg
[   10.873595] usb 2-1.4: new high-speed USB device number 5 using ehci-platform
[   10.971484] usb 2-1.4: New USB device found, idVendor=2c7c, idProduct=6002, bcdDevice= 3.18
[   10.971511] usb 2-1.4: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[   10.971518] usb 2-1.4: Product: Android
[   10.971524] usb 2-1.4: Manufacturer: Android
[   10.971529] usb 2-1.4: SerialNumber: 0000

内核驱动配置

　　4G模块能够正确上电后，需要修改串口驱动，使设备能够被识别成modem，这个步骤主要参考《Quectel_EC200T_Linux_USB_Driver_User_Guide_V1.0》和《Quectel_UMTS_LTE_5G_Linux_USB_Driver_User_Guide_V3.0》。

USB驱动中添加VID和PID

　　修改kernel/drivers/usb/serial/option.c，识别移远4G模块，事实上最新版的SDK已经包含了，因此并不需要做这个步骤。如果后续出了新型号没有包含的话，再手动添加一下。

 245 #define QUECTEL_VENDOR_ID           0x2c7c
 246 /* These Quectel products use Quectel's vendor ID */
 247 #define QUECTEL_PRODUCT_EC21            0x0121
 248 #define QUECTEL_PRODUCT_EC25            0x0125
 249 #define QUECTEL_PRODUCT_EG91            0x0191
 250 #define QUECTEL_PRODUCT_EG95            0x0195
 251 #define QUECTEL_PRODUCT_BG96            0x0296
 252 #define QUECTEL_PRODUCT_EP06            0x0306
 253 #define QUECTEL_PRODUCT_EM12            0x0512
 254 #define QUECTEL_PRODUCT_RM500Q          0x0800
 255 #define QUECTEL_PRODUCT_EC200S_CN       0x6002
 256 #define QUECTEL_PRODUCT_EC200T          0x6026

1098     /* Quectel products using Qualcomm vendor ID */
1099     { USB_DEVICE(QUALCOMM_VENDOR_ID, QUECTEL_PRODUCT_UC15)},
1100     { USB_DEVICE(QUALCOMM_VENDOR_ID, QUECTEL_PRODUCT_UC20),
1101       .driver_info = RSVD(4) },
1102     /* Yuga products use Qualcomm vendor ID */
1103     { USB_DEVICE(QUALCOMM_VENDOR_ID, YUGA_PRODUCT_CLM920_NC5),
1104       .driver_info = RSVD(1) | RSVD(4) },
1105     /* u-blox products using Qualcomm vendor ID */
1106     { USB_DEVICE(QUALCOMM_VENDOR_ID, UBLOX_PRODUCT_R410M),
1107       .driver_info = RSVD(1) | RSVD(3) },
1108     { USB_DEVICE(QUALCOMM_VENDOR_ID, UBLOX_PRODUCT_R6XX),
1109       .driver_info = RSVD(3) },
1110     /* Quectel products using Quectel vendor ID */
1111     { USB_DEVICE_AND_INTERFACE_INFO(QUECTEL_VENDOR_ID, QUECTEL_PRODUCT_EC21, 0xff, 0xff, 0xff),
1112       .driver_info = NUMEP2 },
1113     { USB_DEVICE_AND_INTERFACE_INFO(QUECTEL_VENDOR_ID, QUECTEL_PRODUCT_EC21, 0xff, 0, 0) },
1114     { USB_DEVICE_AND_INTERFACE_INFO(QUECTEL_VENDOR_ID, QUECTEL_PRODUCT_EC25, 0xff, 0xff, 0xff),
1115       .driver_info = NUMEP2 },
1116     { USB_DEVICE_AND_INTERFACE_INFO(QUECTEL_VENDOR_ID, QUECTEL_PRODUCT_EC25, 0xff, 0, 0) },
1117     { USB_DEVICE_AND_INTERFACE_INFO(QUECTEL_VENDOR_ID, QUECTEL_PRODUCT_EG91, 0xff, 0xff, 0xff),
1118       .driver_info = NUMEP2 },
1119     { USB_DEVICE_AND_INTERFACE_INFO(QUECTEL_VENDOR_ID, QUECTEL_PRODUCT_EG91, 0xff, 0, 0) },
1120     { USB_DEVICE_AND_INTERFACE_INFO(QUECTEL_VENDOR_ID, QUECTEL_PRODUCT_EG95, 0xff, 0xff, 0xff),
1121       .driver_info = NUMEP2 },
1122     { USB_DEVICE_AND_INTERFACE_INFO(QUECTEL_VENDOR_ID, QUECTEL_PRODUCT_EG95, 0xff, 0, 0) },
1123     { USB_DEVICE(QUECTEL_VENDOR_ID, QUECTEL_PRODUCT_BG96),
1124       .driver_info = RSVD(4) },
1125     { USB_DEVICE_AND_INTERFACE_INFO(QUECTEL_VENDOR_ID, QUECTEL_PRODUCT_EP06, 0xff, 0xff, 0xff),
1126       .driver_info = RSVD(1) | RSVD(2) | RSVD(3) | RSVD(4) | NUMEP2 },
1127     { USB_DEVICE_AND_INTERFACE_INFO(QUECTEL_VENDOR_ID, QUECTEL_PRODUCT_EP06, 0xff, 0, 0) },
1128     { USB_DEVICE_AND_INTERFACE_INFO(QUECTEL_VENDOR_ID, QUECTEL_PRODUCT_EM12, 0xff, 0xff, 0xff),
1129       .driver_info = RSVD(1) | RSVD(2) | RSVD(3) | RSVD(4) | NUMEP2 },
1130     { USB_DEVICE_AND_INTERFACE_INFO(QUECTEL_VENDOR_ID, QUECTEL_PRODUCT_EM12, 0xff, 0, 0) },
1131     { USB_DEVICE_AND_INTERFACE_INFO(QUECTEL_VENDOR_ID, 0x0620, 0xff, 0xff, 0x30) }, /* EM160R-GL */
1132     { USB_DEVICE_AND_INTERFACE_INFO(QUECTEL_VENDOR_ID, 0x0620, 0xff, 0, 0) },
1133     { USB_DEVICE_AND_INTERFACE_INFO(QUECTEL_VENDOR_ID, QUECTEL_PRODUCT_RM500Q, 0xff, 0xff, 0x30) },
1134     { USB_DEVICE_AND_INTERFACE_INFO(QUECTEL_VENDOR_ID, QUECTEL_PRODUCT_RM500Q, 0xff, 0, 0) },
1135     { USB_DEVICE_AND_INTERFACE_INFO(QUECTEL_VENDOR_ID, QUECTEL_PRODUCT_RM500Q, 0xff, 0xff, 0x10),
1136       .driver_info = ZLP },
1137     { USB_DEVICE_AND_INTERFACE_INFO(QUECTEL_VENDOR_ID, QUECTEL_PRODUCT_EC200S_CN, 0xff, 0, 0) },
1138     { USB_DEVICE_AND_INTERFACE_INFO(QUECTEL_VENDOR_ID, QUECTEL_PRODUCT_EC200T, 0xff, 0, 0) },

添加Zero Packet机制

　　修改kernel/drivers/usb/serial/usb_wwan.c。

static struct urb *usb_wwan_setup_urb(struct usb_serial_port *port,
                          usb_sndbulkpipe(serial->dev, endpoint) | dir,
                          buf, len, callback, ctx);

+       #if 1 //Added by Quectel for zero packet
+       if (dir == USB_DIR_OUT) {
+               struct usb_device_descriptor *desc = &serial->dev->descriptor;
+
+               if (desc->idVendor == cpu_to_le16(0x2C7C))
+                       urb->transfer_flags |= URB_ZERO_PACKET;
+       }
+       #endif
+
        if (intfdata->use_zlp && dir == USB_DIR_OUT)
                urb->transfer_flags |= URB_ZERO_PACKET;

添加Reset-resume机制

　　修改kernel/drivers/usb/serial/option.c。

static struct usb_serial_driver option_1port_device = {
 #ifdef CONFIG_PM
        .suspend           = usb_wwan_suspend,
        .resume            = usb_wwan_resume,
+#if 1 // Added by Quectel
+       .reset_resume      = usb_wwan_resume,
+#endif
 #endif
 };

让网卡被正确的驱动加载

　　修改kernel/drivers/usb/serial/option.c。让模块的网卡被wwan驱动或ecm驱动加载，而不是USB Serial option驱动，这里针对使用wwan的EC20系列和使用ecm的EC200系列略有不同，我直接整合在了一起，这样更换任意系列都能驱动。

static int option_probe(struct usb_serial *serial,
        if (device_flags & NUMEP2 && iface_desc->bNumEndpoints != 2)
                return -ENODEV;

+#if 1 //Added by Quectel
+       if (serial->dev->descriptor.idVendor == cpu_to_le16(0x2C7C)) {
+               __u16 idProduct = le16_to_cpu(serial->dev->descriptor.idProduct);
+
+               // Quectel EC200T's interface 0 can be used as USB Network device (ecm, rndis)
+               if (serial->interface->cur_altsetting->desc.bInterfaceClass != 0xFF)
+                       return -ENODEV;
+
+               struct usb_interface_descriptor *intf = &serial->interface->cur_altsetting->desc;
+
+               if (intf->bInterfaceClass != 0xFF || intf->bInterfaceSubClass == 0x42) {
+                       // ECM, RNDIS, NCM, MBIM, ACM, UAC, ADB
+                       return -ENODEV;
+               }
+
+               if ((idProduct & 0xF000) == 0x0000) {
+                       // MDM interface 4 is QMI
+                       if (intf->bInterfaceNumber == 4 &&
+                               intf->bNumEndpoints == 3 &&
+                               intf->bInterfaceSubClass == 0xFF &&
+                               intf->bInterfaceProtocol == 0xFF)
+                               return -ENODEV;
+                       }
+               }
+#endif
+
        /* Store the device flags so we can use them during attach. */
        usb_set_serial_data(serial, (void *)device_flags);

网卡驱动

　　网卡驱动按照型号分为ECM和WWAN两种，你可以只添加自己需要的，也可以都添加，这样更换4G模块后也能支持使用。

• ECM驱动
• WWAN驱动

　　ECM驱动官方文档说明可以直接使用上游内核的版本，因此直接使能即可，事实上最新版的SDK已经使能了，因此并不需要做这个步骤。

CONFIG_USB_NET_DRIVERS
CONFIG_USB_USBNET
CONFIG_USB_NET_CDCETHER

　　WWAN驱动需要经过修改，但是移远官方提供了一个修改好的版本，直接加入即可使用，这里需要从官方拿到《Quetecl_Linux_Android_QMI_WWAN_Driver_V1.2.2》或更新版本。

1. 将qmi_wwan_q.c复制到kernel/drivers/net/usb/下
2. 在内核配置中使能，事实上最新版的SDK已经使能了，因此并不需要做这个步骤

CONFIG_USB_NET_DRIVERS
CONFIG_USB_USBNET
CONFIG_USB_NET_QMI_WWAN
CONFIG_USB_WDM

3. 修改kernel/drivers/net/usb/Makefile，qmi_wwan_q.o必须添加在qmi_wwan.o之前

+obj-${CONFIG_USB_NET_QMI_WWAN} += qmi_wwan_q.o
 obj-$(CONFIG_USB_NET_QMI_WWAN) += qmi_wwan.o

4. 修改system/core/init/devices.ppp，这一步是否需要未经证实

diff --git a/init/devices.cpp b/init/devices.cpp
index 9fbec641b..719fde8e5 100644
--- a/init/devices.cpp
+++ b/init/devices.cpp
@@ -492,6 +492,10 @@ void DeviceHandler::HandleUevent(const Uevent& uevent) {
             int device_id = uevent.minor % 128 + 1;
             devpath = StringPrintf("/dev/bus/usb/%03d/%03d", bus_id, device_id);
         }
+#if 1 // add by quectel for mknod /dev/cdc-wdm0
+    } else if(uevent.subsystem == "usbmisc" && !uevent.device_name.empty()){
+        devpath = "/dev/" + uevent.device_name;
+#endif
     } else if (StartsWith(uevent.subsystem, "usb")) {
         // ignore other USB events
         return;

使能PPP

　　在内核配置中使能PPP相关的配置，事实上最新版的SDK已经使能了，因此并不需要做这个步骤。

CONFIG_PPP
CONFIG_PPP_ASYNC
CONFIG_PPP_SYNC_TTY
CONFIG_PPP_DEFLATE

测试

　　完成这些步骤后编译刷机上电，正确的话应该能在dmesg日志中认到一个网卡设备，例如如下显示。使用ip addr show命令应该也能看到增加了一个新的接口，usb0或wwan0。

# dmesg
[   10.873595] usb 2-1.4: new high-speed USB device number 5 using ehci-platform
[   10.971484] usb 2-1.4: New USB device found, idVendor=2c7c, idProduct=6002, bcdDevice= 3.18
[   10.971511] usb 2-1.4: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[   10.971518] usb 2-1.4: Product: Android
[   10.971524] usb 2-1.4: Manufacturer: Android
[   10.971529] usb 2-1.4: SerialNumber: 0000
[   10.978405] cdc_ether 2-1.4:1.0 usb0: register 'cdc_ether' at usb-fd880000.usb-1.4, CDC Ethernet Device, ae:0c:29:a3:9b:6d
[   10.979553] option 2-1.4:1.2: GSM modem (1-port) converter detected
[   10.980162] usb 2-1.4: GSM modem (1-port) converter now attached to ttyUSB0
[   10.981357] option 2-1.4:1.3: GSM modem (1-port) converter detected
[   10.982174] usb 2-1.4: GSM modem (1-port) converter now attached to ttyUSB1
[   10.983305] option 2-1.4:1.4: GSM modem (1-port) converter detected
[   10.984216] usb 2-1.4: GSM modem (1-port) converter now attached to ttyUSB2

Android HAL层配置

　　4G模块能够被正确驱动后，需要配置Android的HAL层，这个步骤主要参考《Quectel_Android_RIL_Driver_user_Guide_V2.0》，另外需要拿到RIL驱动。这个驱动很坑，最先使用的是《Quectel_Android_RIL_Driver_V3.5.16_master_beta》，加载时会报找不到已经被废弃的组件"libhidltransport"，后来从技术支持拿到的《Qiectel_Android_RIL_Driver_V3.5.14》才成功驱动，甚至前后两次拿到的V3.5.14版本的驱动，其文件大小和校验还不一样，第一次拿到的也无法驱动。

集成RIL驱动

1. 将驱动中的libquectel-ril/arm64_v8a/libreference-ril.so复制为vendor/rockchip/common/phone/lib/libreference-ril-quectel.so
2. 将驱动中的libquectel-ril/ql-ril.conf复制为vendor/rockchip/common/phone/etc/ql-ril.conf
3. 将ql-ril.conf中LTE_Is_Report_SignalStrength=1信号强度反馈功能的注释删掉，打开此功能
4. 修改vendor/rockchip/common/phone.mk文件，让编译时①和②步骤中的两个文件能够被复制到镜像中

diff --git a/phone/phone.mk b/phone/phone.mk
index 61881e46..c6659f59 100755
--- a/phone/phone.mk
+++ b/phone/phone.mk
@@ -9,6 +9,9 @@ PRODUCT_COPY_FILES += \
     $(CUR_PATH)/phone/etc/ppp/ip-up:system/etc/ppp/ip-up \
     $(CUR_PATH)/phone/etc/ppp/call-pppd:system/etc/ppp/call-pppd \
     $(CUR_PATH)/phone/etc/operator_table:system/etc/operator_table
+PRODUCT_COPY_FILES += \
+    $(CUR_PATH)/phone/lib/libreference-ril-quectel.so:vendor/lib64/libreference-ril-quectel.so \
+    $(CUR_PATH)/phone/etc/ql-ril.conf:system/etc/ql-ril.conf

 ifeq ($(strip $(PRODUCT_MODEM)), DTS4108C)
 PRODUCT_COPY_FILES += \

配置ril-daemon服务

　　修改hardware/ril/rild/rild.rc文件。

diff --git a/rild/rild.rc b/rild/rild.rc
index f6beb54..840cfff 100644
--- a/rild/rild.rc
+++ b/rild/rild.rc
@@ -1,5 +1,11 @@
-service vendor.ril-daemon /vendor/bin/hw/rild
+# service vendor.ril-daemon /vendor/bin/hw/rild
+#     class main
+#     user radio
+#     group radio cache inet misc audio log readproc wakelock
+#     capabilities BLOCK_SUSPEND NET_ADMIN NET_RAW
+
+service ril-daemon /vendor/bin/hw/rild -l /vendor/lib64/libreference-ril-quectel.so
     class main
-    user radio
-    group radio cache inet misc audio log readproc wakelock
+    user root
+    group radio cache inet misc audio sdcard_rw log
     capabilities BLOCK_SUSPEND NET_ADMIN NET_RAW

增加HIDL描述清单文件

　　按照移远的文档，正常该文件应该位于device/rockchip/common/manifest.xml，RK将这部分内容单独提取到了device/rockchip/common/4g_modem/manifest.xml，编译时会自动合入。另外RK的Android 11的SDK尚不支持IRadio 1.4，因此配置成IRadio 1.1即可，事实上最新版的SDK已经配置了，因此并不需要做这个步骤。

<hal format="hidl">
    <name>android.hardware.radio</name>
    <transport>hwbinder</transport>
    <fqname>@1.1::IRadio/slot1</fqname>
    <fqname>@1.1::IRadio/slot2</fqname>
    <fqname>@1.2::ISap/slot1</fqname>
</hal>

添加SELinux配置

　　这一部分可以直接参考移远的官方文档，文件目录分别位于：

• device/rockchip/common/ueventd.rockchip.rc
• device/rockchip/common/sepolicy/private/file_contexts
• system/sepolicy/vendor/rild.te

替换RK自带的ril服务

　　修改device/rockchip/common/device.mk文件。

diff --git a/device.mk b/device.mk
index 917e8b9..4b74549 100644
--- a/device.mk
+++ b/device.mk
@@ -259,7 +259,7 @@ PRODUCT_PACKAGES += \
     CarrierDefaultApp \
     CarrierConfig \
     rild \
-    librk-ril \
+    libreference-ril-quectel \
     dhcpcd

 PRODUCT_COPY_FILES += vendor/rockchip/common/phone/etc/apns-full-conf.xml:$(TARGET_COPY_OUT_PRODUCT)/etc/apns-conf.xml
@@ -274,7 +274,7 @@ PRODUCT_PROPERTY_OVERRIDES += \

 ifeq ($(strip $(TARGET_ARCH)), arm64)
 PRODUCT_PROPERTY_OVERRIDES += \
-               vendor.rild.libpath=/vendor/lib64/librk-ril.so
+               vendor.rild.libpath=/vendor/lib64/libreference-ril-quectel.so

 PRODUCT_COPY_FILES += \
                $(LOCAL_PATH)/4g_modem/bin64/dhcpcd:$(TARGET_COPY_OUT_VENDOR)/bin/dhcpcd \

在板级配置中使能相关配置

　　修改板级BoardConfig.mk文件。

BOARD_HAS_RK_4G_MODEM := true
BOARD_HAVE_DONGLE := true

　　修改板级alpha.mk文件，EC200系列的/dev/ttyUSB2是modem，其他系列具体请查询移远的文档。另外这里注意rild.libargs中的-d与后面的/dev/ttyUSB2中间不能有空格。

PRODUCT_PROPERTY_OVERRIDES += \
    rild.libpath=/vendor/lib64/libreference-ril-quectel.so \
    rild.libargs=-d/dev/ttyUSB2 \

修复usb_dongle的编译错误

　　修改external/usb_modeswitch/usb_dongle/Android.mk文件。

diff --git a/usb_dongle/Android.mk b/usb_dongle/Android.mk
index 1ee43ff..d16ca37 100755
--- a/usb_dongle/Android.mk
+++ b/usb_dongle/Android.mk
@@ -19,7 +19,8 @@ common_shared_libraries := \

 common_cflags := -Werror -Wall -Wno-missing-field-initializers -Wno-unused-variable -Wno-unused-parameter

-common_local_tidy_flags := -warnings-as-errors=clang-analyzer-security*,cert-*
+#common_local_tidy_flags := -warnings-as-errors=clang-analyzer-security*,cert-*
+common_local_tidy_flags := -warnings-as-errors=clang-analyzer-security*
 common_local_tidy_checks := -*,clang-analyzer-security*,cert-*,-cert-err34-c,-cert-err58-cpp
 common_local_tidy_checks += ,-cert-env33-c

在设置中新增“移动网络”选项

　　修改device/rockchip/rk356x/overlay/frameworks/base/core/res/res/values/config.xml文件。

diff --git a/overlay/frameworks/base/core/res/res/values/config.xml b/overlay/frameworks/base/core/res/res/values/config.xml
index 9feb244..0a6bc4c 100755
--- a/overlay/frameworks/base/core/res/res/values/config.xml
+++ b/overlay/frameworks/base/core/res/res/values/config.xml
@@ -31,9 +31,16 @@
     <!-- the 6th element indicates boot-time dependency-met value. -->
     <string-array translatable="false" name="networkAttributes">
         <item>"wifi,1,1,2,-1,true"</item>
+        <item>"mobile,0,0,0,-1,true"</item>
+        <item>"mobile_mms,2,0,2,60000,false"</item>
+        <item>"mobile_supl,3,0,2,60000,true"</item>
+        <item>"mobile_dun,4,0,2,60000,true"</item>
         <item>"bluetooth,7,7,0,-1,true"</item>
         <item>"ethernet,9,9,9,-1,true"</item>
     </string-array>
+
+    <bool name="config_voice_capable">true</bool>
+
     <!-- Flag indicating whether we should enable the automatic brightness in Settings.
          config_hardware_automatic_brightness_available is not set, so we will use software implementation -->
     <bool name="config_automatic_brightness_available">true</bool>

添加APN配置

　　RK自带的已经可以正常使用，文件位于vendor/rockchip/common/phone/etc/apns-full-conf.xml。

测试

　　完成这些步骤后编译刷机上电，正确的话界面应该可以看到4G图标并上网。使用ip addr show命令应该也能看到usb0或wwan0接口已经获取到了IP地址。

参考文献

• RK3568-ANDROID11-4G-EC20-系统篇（移远模块）
• RK3568移远4G模块EC20
• [RK3568 Android11] 开发之4G模块（移远模块）