怎样在RK3399上去移植4G模块呢

1、通过串口打印或者adb获取模块的 pid 和 vid，顺便可以看到生成 4 个虚拟串口 /dev/ttyUSB*

[   11.734379] u*** 1-1.1: new high-speed USB device number 3 using ehci-platform
[   11.828247] u*** 1-1.1: New USB device found, idVendor=2c7c, idProduct=0125
[   11.828386] u*** 1-1.1: New USB device strings: Mfr=1, Product=2, SerialNumber=0
[   11.828413] u*** 1-1.1: Product: Android
[   11.828436] u*** 1-1.1: Manufacturer: Android
[   11.835480] option 1-1.1:1.0: GSM modem (1-port) converter detected
[   11.841217] u*** 1-1.1: GSM modem (1-port) converter now attached to ttyUSB0
[   11.844988] option 1-1.1:1.1: GSM modem (1-port) converter detected
[   11.851892] u*** 1-1.1: GSM modem (1-port) converter now attached to ttyUSB1
[   11.853964] option 1-1.1:1.2: GSM modem (1-port) converter detected
[   11.864677] u*** 1-1.1: GSM modem (1-port) converter now attached to ttyUSB2
[   11.865658] option 1-1.1:1.3: GSM modem (1-port) converter detected
[   11.871387] u*** 1-1.1: GSM modem (1-port) converter now attached to ttyUSB3
2、在代码中添加模块的 pid 和 vid，原始代码中已经包含移远的几个模块，仿照现有的添加 EC20

diff --git a/kernel/drivers/u***/serial/option.c b/kernel/drivers/u***/serial/option.c
index 1799aa0..f6c9e5d 100644
--- a/kernel/drivers/u***/serial/option.c
+++ b/kernel/drivers/u***/serial/option.c
@@ -241,6 +241,7 @@ static void option_instat_callback(struct urb *urb);

#define QUECTEL_VENDOR_ID                      0x2c7c
/* These Quectel products use Quectel's vendor ID */
+#define QUECTEL_PRODUCT_EC20                   0x0125
#define QUECTEL_PRODUCT_EC21                   0x0121
#define QUECTEL_PRODUCT_EC25                   0x0125
#define QUECTEL_PRODUCT_BG96                   0x0296
@@ -1200,6 +1201,8 @@ static const struct u***_device_id option_ids[] = {
        { USB_DEVICE(QUALCOMM_VENDOR_ID, YUGA_PRODUCT_CLM920_NC5),
          .driver_info = (kernel_ulong_t)&yuga_clm920_nc5_blacklist },
        /* Quectel products using Quectel vendor ID */
+       { USB_DEVICE(QUECTEL_VENDOR_ID, QUECTEL_PRODUCT_EC20),
+         .driver_info = (kernel_ulong_t)&net_intf4_blacklist },
        { USB_DEVICE(QUECTEL_VENDOR_ID, QUECTEL_PRODUCT_EC21),
          .driver_info = (kernel_ulong_t)&net_intf4_blacklist },
        { USB_DEVICE(QUECTEL_VENDOR_ID, QUECTEL_PRODUCT_EC25)
3、添加模块的 so 库，此库需要移远提供，so 支持的系统要匹配，将 so 库拷贝到下面的路径

vendor/rockchip/common/phone/lib/libreference-ril.so
4、打开 device/rockchip/common/device.mk 文件，修改 rild.libpath 路径为 rild.libpath=/system/lib64/libreference-ril.so

diff --git a/device/rockchip/common/device.mk b/device/rockchip/common/device.mk
index be2cb2c..69034a7 100755
--- a/device/rockchip/common/device.mk
+++ b/device/rockchip/common/device.mk
@@ -699,7 +699,7 @@ endif
ifeq ($(strip $(BOARD_HAVE_DONGLE)),true)
ifeq ($(strip $(TARGET_ARCH)), arm64)
PRODUCT_PROPERTY_OVERRIDES +=
-    rild.libpath=/system/lib64/libril-rk29-dataonly.so
+    rild.libpath=/system/lib64/libreference-ril.so
else
PRODUCT_PROPERTY_OVERRIDES +=
     rild.libpath=/system/lib/libril-rk29-dataonly.so
因为 rk3399 是64位 CPU，所以 ifeq ($(strip $(TARGET_ARCH)), arm64) 条件成立。

但是前提都是 BOARD_HAVE_DONGLE 变量值为 true

5、编译时将 so 库拷贝到上面指定目录 /system/lib64/libreference-ril.so

diff --git a/vendor/rockchip/common/phone/phone.mk b/vendor/rockchip/common/phone/phone.mk
index 946aacd..f8fc6e7 100755
--- a/vendor/rockchip/common/phone/phone.mk
+++ b/vendor/rockchip/common/phone/phone.mk
@@ -8,7 +8,8 @@ PRODUCT_COPY_FILES +=
     $(CUR_PATH)/phone/etc/ppp/ip-down:system/etc/ppp/ip-down
     $(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
+    $(CUR_PATH)/phone/etc/operator_table:system/etc/operator_table
+    $(CUR_PATH)/phone/lib/libreference-ril.so:system/lib64/libreference-ril.so

ifeq ($(strip $(PRODUCT_MODEM)), DTS4108C)
PRODUCT_COPY_FILES +=
6、设置 BOARD_HAVE_DONGLE 变量

diff --git a/device/rockchip/rk3399/rk3399_all.mk b/device/rockchip/rk3399/rk3399_all.mk
index 7a2d870..ce5060c 100755
--- a/device/rockchip/rk3399/rk3399_all.mk
+++ b/device/rockchip/rk3399/rk3399_all.mk
@@ -63,7 +63,7 @@ BOARD_NFC_SUPPORT := false
BOARD_HAS_GPS := false

#for 3G/4G modem dongle support
-BOARD_HAVE_DONGLE := false
+BOARD_HAVE_DONGLE := true


BOARD_GRAVITY_SENSOR_SUPPORT := true
此时移植完成，只要 so 库没问题，就可以正常上网。


如果 radio log 中打印如下信息：

RIL_SAP_Init not defined or exported in /system/lib64/libril-rk29-dataonly.so不影响使用，RIL_SAP_Init初始化BT协议的。