20240107移远的4G模块EC20在Firefly的AIO-3399J开发板的Android11下调通能上网
 2024/1/7 11:17
 开发板:Firefly的AIO-3399J【RK3399】
SDK:rk3399-android-11-r20211216.tar.xz【Android11】
 Android11.0.tar.bz2.aa【ToyBrick】
 Android11.0.tar.bz2.ab
 Android11.0.tar.bz2.ac
https://wiki.t-firefly.com/AIO-3399J/prepare_compile_android.html
 AIO-3399J产品规格书 立即购买
 AIO-3399J 采用 RK3399 六核(A72x2+A53x4) 64 位处理器,主频高达1.8GHz,集成了四核 Mali-T860 GPU,性能优异。
 0、简略步骤:
rootroot@rootroot-X99-Turbo:~/3TB$ cat Android11.0.tar.bz2.a* > Android11.0.tar.bz2
 rootroot@rootroot-X99-Turbo:~/3TB$ tar jxvf Android11.0.tar.bz2 
 rootroot@rootroot-X99-Turbo:~/3TB$ mv Android11.0 64rk3399-android-11
 rootroot@rootroot-X99-Turbo:~/3TB$ cd 64rk3399-android-11
 rootroot@rootroot-X99-Turbo:~/3TB/64rk3399-android-11$ cd u-boot
 rootroot@rootroot-X99-Turbo:~/3TB/64rk3399-android-11/u-boot$ ./make.sh rk3399
 rootroot@rootroot-X99-Turbo:~/3TB/64rk3399-android-11/u-boot$ cd ..
 rootroot@rootroot-X99-Turbo:~/3TB/64rk3399-android-11$ cd kernel/
 rootroot@rootroot-X99-Turbo:~/3TB/64rk3399-android-11/kernel$ make ARCH=arm64 rockchip_defconfig android-11.config -j36
 rootroot@rootroot-X99-Turbo:~/3TB/64rk3399-android-11/kernel$ make ARCH=arm64 BOOT_IMG=../rockdev/Image-rk3399_Android11/boot.img rk3399-sapphire-excavator-edp-avb.img -j36
 rootroot@rootroot-X99-Turbo:~/3TB/64rk3399-android-11$ source build/envsetup.sh 
 rootroot@rootroot-X99-Turbo:~/3TB/64rk3399-android-11$ lunch
      36. rk3399_Android11-userdebug
 Which would you like? [aosp_arm-eng] 36
 rootroot@rootroot-X99-Turbo:~/3TB/64rk3399-android-11$ 
 rootroot@rootroot-X99-Turbo:~/3TB/64rk3399-android-11$ make -j36
 rootroot@rootroot-X99-Turbo:~/3TB/64rk3399-android-11$ ./build.sh -u
 Android部分:【完全一致/相同】
 1、
 Z:\rk3399-android-11\device\rockchip\common\4g_modem\manifest.xml
 <manifest version="1.0" type="device">
     <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>
     <hal format="hidl">
         <name>android.hardware.radio.deprecated</name>
         <transport>hwbinder</transport>
         <version>1.0</version>
         <interface>
             <name>IOemHook</name>
             <instance>slot1</instance>
         </interface>
     </hal>
     <hal format="hidl">
         <name>android.hardware.radio.config</name>
         <transport>hwbinder</transport>
         <version>1.0</version>
         <interface>
             <name>IRadioConfig</name>
             <instance>default</instance>
         </interface>
     </hal>
 </manifest>

 2、复制库文件:【貌似没用?】
chat
 dhcpcd
 ip-down
 ip-up
 libmeig-ril.so
 libquec-ril.so
 libreference-ril-62.so
 libreference-ril.so
Z:\rk3399-android-11\device\rockchip\common\ec20\chat
 Z:\rk3399-android-11\device\rockchip\common\ec20\dhcpcd
 Z:\rk3399-android-11\device\rockchip\common\ec20\ip-down
 Z:\rk3399-android-11\device\rockchip\common\ec20\ip-up
 Z:\rk3399-android-11\device\rockchip\common\ec20\libmeig-ril.so
 Z:\rk3399-android-11\device\rockchip\common\ec20\libquec-ril.so
 Z:\rk3399-android-11\device\rockchip\common\ec20\libreference-ril-62.so
 Z:\rk3399-android-11\device\rockchip\common\ec20\libreference-ril.so

 3、
 Z:\rk3399-android-11\device\rockchip\common\BoardConfig.mk
 #for rk 4g modem
BOARD_HAS_RK_4G_MODEM ?= false
 修改为:
#for rk 4g modem 2024/1/5 23:36
 BOARD_HAS_RK_4G_MODEM ?= false
#for ec20 modem 2024/1/5 22:25
 BOARD_HAS_EC20_MODEM ?= true
ifeq ($(strip $(BOARD_HAS_EC20_MODEM)),true)
 DEVICE_MANIFEST_FILE += device/rockchip/common/4g_modem/manifest.xml
 endif
#for ec20 modem 2024/1/7 22:25

 4、
 Z:\rk3399-android-11\device\rockchip\common\device.mk
ifeq ($(strip $(TARGET_ARCH)), arm64)
 PRODUCT_PROPERTY_OVERRIDES += \
     vendor.rild.libpath=/vendor/lib64/librk-ril.so
PRODUCT_COPY_FILES += \
     $(LOCAL_PATH)/4g_modem/bin64/dhcpcd:$(TARGET_COPY_OUT_VENDOR)/bin/dhcpcd \
     $(LOCAL_PATH)/4g_modem/lib64/librk-ril.so:$(TARGET_COPY_OUT_VENDOR)/lib64/librk-ril.so
 else
 PRODUCT_PROPERTY_OVERRIDES += \
     vendor.rild.libpath=/vendor/lib/librk-ril.so
PRODUCT_COPY_FILES += \
     $(LOCAL_PATH)/4g_modem/bin32/dhcpcd:$(TARGET_COPY_OUT_VENDOR)/bin/dhcpcd \
     $(LOCAL_PATH)/4g_modem/lib32/librk-ril.so:$(TARGET_COPY_OUT_VENDOR)/lib/librk-ril.so
endif
 endif
#for ec20 modem 2024/1/5 22:25
 ifeq ($(strip $(BOARD_HAS_EC20_MODEM)),true)
 PRODUCT_COPY_FILES += \
                       device/rockchip/common/ec20/libquec-ril.so:vendor/lib64/libquec-ril.so \
                       device/rockchip/common/ec20/libmeig-ril.so:vendor/lib64/libmeig-ril.so \
                       device/rockchip/common/ec20/chat:system/bin/chat \
                       device/rockchip/common/ec20/ip-up:system/etc/ppp/ip-up \
                       device/rockchip/common/ec20/ip-down:system/etc/ppp/ip-down \
                       device/rockchip/common/ec20/dhcpcd:$(TARGET_COPY_OUT_VENDOR)/bin/dhcpcd
PRODUCT_COPY_FILES += vendor/rockchip/common/phone/etc/apns-full-conf.xml:$(TARGET_COPY_OUT_PRODUCT)/etc/apns-conf.xml
PRODUCT_PACKAGES += \
                    rild \
                    dhcpcd \
                    CarrierDefaultApp \
                    CarrierConfig
PRODUCT_PROPERTY_OVERRIDES += \
                       ro.boot.noril=false \
                       ro.telephony.default_network=9
PRODUCT_PACKAGES += \
                       android.hardware.radio@1.2-radio-service \
                       android.hardware.radio.config@1.0-service
PRODUCT_PROPERTY_OVERRIDES += \
                       vendor.rild.libpath=/vendor/lib64/libquec-ril.so
 endif
 #for ec20 modem 2024/1/7 22:25

 5、
 Z:\rk3399-android-11\device\rockchip\common\ueventd.rockchip.rc
# for serial
 /dev/ttyS4                0660   system     system
# for radio
 /dev/ttyUSB*              0660   system     radio
 /dev/cdc-wdm0             0660   system     radio
# for mali-t764
 /dev/mali0                 0666   system        system
 修改为:
# for serial
 /dev/ttyS4                0660   system     system
#for ec20 modem 2024/1/5 22:25
 # for radio
/dev/ttyUSB*              0660   radio     radio
 /dev/ttyACM*              0666   radio          radio
 /dev/cdc-wdm*             0666   radio          radio
 /dev/qcqmi*               0660   radio          radio
 #for ec20 modem 2024/1/5 22:25
# for mali-t764
 /dev/mali0                 0666   system        system

 6、
 Z:\rk3399-android-11\device\rockchip\rk3399\rk3399_Android11\overlay\frameworks\base\core\res\res\values\config.xml
<?xml version="1.0" encoding="utf-8"?>
 <!--
 /*
 ** Copyright 2009, The Android Open Source Project
 **
 ** Licensed under the Apache License, Version 2.0 (the "License");
 ** you may not use this file except in compliance with the License.
 ** You may obtain a copy of the License at
 **
 **     http://www.apache.org/licenses/LICENSE-2.0
 **
 ** Unless required by applicable law or agreed to in writing, software
 ** distributed under the License is distributed on an "AS IS" BASIS,
 ** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 ** See the License for the specific language governing permissions and
 ** limitations under the License.
 */
 -->
<resources>
     <!-- This string array should be overridden by the device to present a list of network
          attributes.  This is used by the connectivity manager to decide which networks can coexist
          based on the hardware -->
     <!-- An Array of "[Connection name],[ConnectivityManager connection type],
          [associated radio-type],[priority],[restoral-timer(ms)],[dependencyMet]  -->
     <!-- the 5th element "resore-time" indicates the number of milliseconds to delay
          before automatically restore the default connection.  Set -1 if the connection
          does not require auto-restore. -->
     <!-- 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,true"</item>
          <item>"mobile_supl,3,0,2,60000,true"</item>
          <item>"mobile_dun,4,0,2,60000,true"</item>
          <item>"mobile_hipri,5,0,3,60000,true"</item>
          <item>"mobile_fota,10,0,2,60000,true"</item>
          <item>"mobile_ims,11,0,2,60000,true"</item>
          <item>"mobile_cbs,12,0,2,60000,true"</item>
        <item>"bluetooth,7,7,0,-1,true"</item>
         <item>"ethernet,9,9,9,-1,true"</item>
 <!--add by blb-->
         <item>"pppoe,15,15,5,-1,true"</item>
     </string-array>
     <!-- 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>

 【不用修改】
 Z:\rk3399-android-11\device\rockchip\rk3399\device.mk
 7、
 Z:\rk3399-android-11\kernel\drivers\net\usb\Makefile
 # SPDX-License-Identifier: GPL-2.0
 #
 # Makefile for USB Network drivers
 #
obj-$(CONFIG_USB_CATC)        += catc.o
 obj-$(CONFIG_USB_KAWETH)    += kaweth.o
 obj-$(CONFIG_USB_PEGASUS)    += pegasus.o
 obj-$(CONFIG_USB_RTL8150)    += rtl8150.o
 obj-$(CONFIG_USB_RTL8152)    += r8152.o
 obj-$(CONFIG_USB_HSO)        += hso.o
 obj-$(CONFIG_USB_LAN78XX)    += lan78xx.o
 obj-$(CONFIG_USB_NET_AX8817X)    += asix.o
 asix-y := asix_devices.o asix_common.o ax88172a.o
 obj-$(CONFIG_USB_NET_AX88179_178A)      += ax88179_178a.o
 obj-$(CONFIG_USB_NET_CDCETHER)    += cdc_ether.o
 obj-$(CONFIG_USB_NET_CDC_EEM)    += cdc_eem.o
 obj-$(CONFIG_USB_NET_DM9601)    += dm9601.o
 obj-$(CONFIG_USB_NET_SR9700)    += sr9700.o
 obj-$(CONFIG_USB_NET_SR9800)    += sr9800.o
 obj-$(CONFIG_USB_NET_SMSC75XX)    += smsc75xx.o
 obj-$(CONFIG_USB_NET_SMSC95XX)    += smsc95xx.o
 obj-$(CONFIG_USB_NET_GL620A)    += gl620a.o
 obj-$(CONFIG_USB_NET_NET1080)    += net1080.o
 obj-$(CONFIG_USB_NET_PLUSB)    += plusb.o
 obj-$(CONFIG_USB_NET_RNDIS_HOST)    += rndis_host.o
 obj-$(CONFIG_USB_NET_CDC_SUBSET_ENABLE)    += cdc_subset.o
 obj-$(CONFIG_USB_NET_ZAURUS)    += zaurus.o
 obj-$(CONFIG_USB_NET_MCS7830)    += mcs7830.o
 obj-$(CONFIG_USB_USBNET)    += usbnet.o
 obj-$(CONFIG_USB_NET_INT51X1)    += int51x1.o
 obj-$(CONFIG_USB_CDC_PHONET)    += cdc-phonet.o
 obj-$(CONFIG_USB_NET_KALMIA)    += kalmia.o
 obj-$(CONFIG_USB_IPHETH)    += ipheth.o
 obj-$(CONFIG_USB_SIERRA_NET)    += sierra_net.o
 obj-$(CONFIG_USB_NET_CX82310_ETH)    += cx82310_eth.o
 obj-$(CONFIG_USB_NET_CDC_NCM)    += cdc_ncm.o
 obj-$(CONFIG_USB_NET_HUAWEI_CDC_NCM)    += huawei_cdc_ncm.o
 obj-$(CONFIG_USB_VL600)        += lg-vl600.o
#obj-$(CONFIG_USB_NET_QMI_WWAN)    += qmi_wwan.o
 obj-$(CONFIG_USB_NET_QMI_WWAN) += qmi_wwan_q.o
 obj-$(CONFIG_USB_NET_CDC_MBIM)    += cdc_mbim.o
 obj-$(CONFIG_USB_NET_CH9200)    += ch9200.o
 Z:\rk3399-android-11\kernel\drivers\net\usb\qmi_wwan_q.c
/*
  * Copyright (c) 2012  Bjørn Mork <bjorn@mork.no>
  *
  * The probing code is heavily inspired by cdc_ether, which is:
  * Copyright (C) 2003-2005 by David Brownell
  * Copyright (C) 2006 by Ole Andre Vadla Ravnas (ActiveSync)
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License
  * version 2 as published by the Free Software Foundation.
  */
  
 #include <linux/module.h>
 #include <linux/netdevice.h>
 #include <linux/ethtool.h>
 #include <linux/etherdevice.h>
 #include <linux/mii.h>
 #include <linux/usb.h>
 #include <linux/usb/cdc.h>
 #include <linux/usb/usbnet.h>
 #include <linux/usb/cdc-wdm.h>
  
 /* This driver supports wwan (3G/LTE/?) devices using a vendor
  * specific management protocol called Qualcomm MSM Interface (QMI) -
  * in addition to the more common AT commands over serial interface
  * management
  *
  * QMI is wrapped in CDC, using CDC encapsulated commands on the
  * control ("master") interface of a two-interface CDC Union
  * resembling standard CDC ECM.  The devices do not use the control
  * interface for any other CDC messages.  Most likely because the
  * management protocol is used in place of the standard CDC
  * notifications NOTIFY_NETWORK_CONNECTION and NOTIFY_SPEED_CHANGE
  *
  * Alternatively, control and data functions can be combined in a
  * single USB interface.
  *
  * Handling a protocol like QMI is out of the scope for any driver.
  * It is exported as a character device using the cdc-wdm driver as
  * a subdriver, enabling userspace applications ("modem managers") to
  * handle it.
  *
  * These devices may alternatively/additionally be configured using AT
  * commands on a serial interface
  */
  
 /* driver specific data */
 struct qmi_wwan_state {
     struct usb_driver *subdriver;
     atomic_t pmcount;
     unsigned long unused;
     struct usb_interface *control;
     struct usb_interface *data;
 };
  
 /* default ethernet address used by the modem */
 static const u8 default_modem_addr[ETH_ALEN] = {0x02, 0x50, 0xf3};
  
 #if 1 //Added by Quectel
 #include <linux/etherdevice.h>
 #include <net/arp.h>
 #include <net/ip.h>
 #include <net/ipv6.h>
  
 /*
     Quectel_WCDMA<E_Linux_USB_Driver_User_Guide_V1.9.pdf
     5.6.    Test QMAP on GobiNet or QMI WWAN
     0 - no QMAP
     1 - QMAP (Aggregation protocol)
     X - QMAP (Multiplexing and Aggregation protocol)
 */
 #define QUECTEL_WWAN_QMAP 4
  
 #if defined(QUECTEL_WWAN_QMAP)
 #define QUECTEL_QMAP_MUX_ID 0x81
  
 static uint __read_mostly qmap_mode = 0;
 module_param( qmap_mode, uint, S_IRUGO);
 module_param_named( rx_qmap, qmap_mode, uint, S_IRUGO );
 #endif
  
 #ifdef CONFIG_BRIDGE
 //#define QUECTEL_BRIDGE_MODE
 #endif
  
 #ifdef QUECTEL_BRIDGE_MODE
 static uint __read_mostly bridge_mode = BIT(0)/*|BIT(1)*/;
 module_param( bridge_mode, uint, S_IRUGO );
 #endif
  
 #if defined(QUECTEL_WWAN_QMAP)
 typedef struct sQmiWwanQmap
 {
     struct usbnet *mpNetDev;
     atomic_t refcount;
     struct net_device *mpQmapNetDev[QUECTEL_WWAN_QMAP];
     uint link_state;
     uint qmap_mode;
 #ifdef QUECTEL_BRIDGE_MODE
     uint bridge_mode;
     uint bridge_ipv4;
     unsigned char bridge_mac[ETH_ALEN];
 #endif
 } sQmiWwanQmap;
  
 struct qmap_priv {
     struct net_device *real_dev;
     u8 offset_id;
 #ifdef QUECTEL_BRIDGE_MODE
     uint bridge_mode;
     uint bridge_ipv4;
     unsigned char bridge_mac[ETH_ALEN];
 #endif
 };
  
 struct qmap_hdr {
     u8 cd_rsvd_pad;
     u8 mux_id;
     u16 pkt_len;
 } __packed;
  
 #ifdef QUECTEL_BRIDGE_MODE
 static int is_qmap_netdev(const struct net_device *netdev);
 #endif
 #endif
  
 #ifdef QUECTEL_BRIDGE_MODE
 static int bridge_arp_reply(struct net_device *net, struct sk_buff *skb, uint bridge_ipv4) {
     struct arphdr *parp;
     u8 *arpptr, *sha;
     u8  sip[4], tip[4], ipv4[4];
     struct sk_buff *reply = NULL;
  
     ipv4[0]  = (bridge_ipv4 >> 24) & 0xFF;
     ipv4[1]  = (bridge_ipv4 >> 16) & 0xFF;
     ipv4[2]  = (bridge_ipv4 >> 8) & 0xFF;
     ipv4[3]  = (bridge_ipv4 >> 0) & 0xFF;
         
     parp = arp_hdr(skb);
  
     if (parp->ar_hrd == htons(ARPHRD_ETHER)  && parp->ar_pro == htons(ETH_P_IP)
         && parp->ar_op == htons(ARPOP_REQUEST) && parp->ar_hln == 6 && parp->ar_pln == 4) {
         arpptr = (u8 *)parp + sizeof(struct arphdr);
         sha = arpptr;
         arpptr += net->addr_len;    /* sha */
         memcpy(sip, arpptr, sizeof(sip));
         arpptr += sizeof(sip);
         arpptr += net->addr_len;    /* tha */
         memcpy(tip, arpptr, sizeof(tip));
  
         pr_info("%s sip = %d.%d.%d.%d, tip=%d.%d.%d.%d, ipv4=%d.%d.%d.%d\n", netdev_name(net),
             sip[0], sip[1], sip[2], sip[3], tip[0], tip[1], tip[2], tip[3], ipv4[0], ipv4[1], ipv4[2], ipv4[3]);
     //wwan0 sip = 10.151.137.255, tip=10.151.138.0, ipv4=10.151.137.255
         if (tip[0] == ipv4[0] && tip[1] == ipv4[1] && (tip[2]&0xFC) == (ipv4[2]&0xFC) && tip[3] != ipv4[3])
             reply = arp_create(ARPOP_REPLY, ETH_P_ARP, *((__be32 *)sip), net, *((__be32 *)tip), sha, default_modem_addr, sha);
  
         if (reply) {
             skb_reset_mac_header(reply);
             __skb_pull(reply, skb_network_offset(reply));
             reply->ip_summed = CHECKSUM_UNNECESSARY;
             reply->pkt_type = PACKET_HOST;
  
             netif_rx_ni(reply);
         }
         return 1;
     }
  
     return 0;
 }
  
 static struct sk_buff *bridge_mode_tx_fixup(struct net_device *net, struct sk_buff *skb, uint bridge_ipv4, unsigned char *bridge_mac) {
     struct ethhdr *ehdr;
     const struct iphdr *iph;
     
     skb_reset_mac_header(skb);
     ehdr = eth_hdr(skb);    
  
     if (ehdr->h_proto == htons(ETH_P_ARP)) {
         if (bridge_ipv4)
             bridge_arp_reply(net, skb, bridge_ipv4);
         return NULL;
     }
  
     iph = ip_hdr(skb);
     //DBG("iphdr: ");
     //PrintHex((void *)iph, sizeof(struct iphdr));
  
 // 1    0.000000000    0.0.0.0    255.255.255.255    DHCP    362    DHCP Request  - Transaction ID 0xe7643ad7        
     if (ehdr->h_proto == htons(ETH_P_IP) && iph->protocol == IPPROTO_UDP && iph->saddr == 0x00000000 && iph->daddr == 0xFFFFFFFF) {
         //if (udp_hdr(skb)->dest == htons(67)) //DHCP Request
         {
             memcpy(bridge_mac, ehdr->h_source, ETH_ALEN);
             pr_info("%s PC Mac Address: %02x:%02x:%02x:%02x:%02x:%02x\n", netdev_name(net),
                 bridge_mac[0], bridge_mac[1], bridge_mac[2], bridge_mac[3], bridge_mac[4], bridge_mac[5]);
         }
     }
         
     if (memcmp(ehdr->h_source, bridge_mac, ETH_ALEN)) {
         return NULL;
     }
  
     return skb;
 }
 #endif
  
 #if defined(QUECTEL_WWAN_QMAP)
 static ssize_t qmap_mode_show(struct device *dev, struct device_attribute *attr, char *buf) {
     struct net_device *netdev = to_net_dev(dev);
     struct usbnet * usbnetdev = netdev_priv( netdev );
     struct qmi_wwan_state *info = (void *)&usbnetdev->data;
     sQmiWwanQmap *pQmapDev = (sQmiWwanQmap *)info->unused;
  
     return snprintf(buf, PAGE_SIZE, "%d\n",  pQmapDev->qmap_mode);
 }
  
 static DEVICE_ATTR(qmap_mode, S_IRUGO, qmap_mode_show, NULL);
  
 static ssize_t link_state_show(struct device *dev, struct device_attribute *attr, char *buf) {
     struct net_device *netdev = to_net_dev(dev);
     struct usbnet * usbnetdev = netdev_priv( netdev );
     struct qmi_wwan_state *info = (void *)&usbnetdev->data;
     sQmiWwanQmap *pQmapDev = (sQmiWwanQmap *)info->unused;
  
     return snprintf(buf, PAGE_SIZE, "0x%x\n",  pQmapDev->link_state);
 }
  
 static ssize_t link_state_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) {
     struct net_device *netdev = to_net_dev(dev);
     struct usbnet * usbnetdev = netdev_priv( netdev );
     struct qmi_wwan_state *info = (void *)&usbnetdev->data;
     sQmiWwanQmap *pQmapDev = (sQmiWwanQmap *)info->unused;
     unsigned link_state = 0;
     unsigned old_link = pQmapDev->link_state;
  
     link_state = simple_strtoul(buf, NULL, 0);
     if (pQmapDev->qmap_mode == 1)
         pQmapDev->link_state = !!link_state;
     else if (pQmapDev->qmap_mode > 1) {
         if (0 < link_state && link_state <= pQmapDev->qmap_mode)
             pQmapDev->link_state |= (1 << (link_state - 1));
         else if (0x80 < link_state && link_state <= (0x80 + pQmapDev->qmap_mode))
             pQmapDev->link_state &= ~(1 << ((link_state&0xF) - 1));
     }
  
     if (old_link != pQmapDev->link_state)
         dev_info(dev, "link_state 0x%x -> 0x%x\n", old_link, pQmapDev->link_state);
  
     return count;
 }
  
 #ifdef QUECTEL_BRIDGE_MODE
 static ssize_t bridge_mode_show(struct device *dev, struct device_attribute *attr, char *buf) {
     struct net_device *netdev = to_net_dev(dev);
     uint bridge_mode = 0;
  
     if (is_qmap_netdev(netdev)) {
         struct qmap_priv *priv = netdev_priv(netdev);
         bridge_mode = priv->bridge_mode;    
     }
     else {
         struct usbnet * usbnetdev = netdev_priv( netdev );
         struct qmi_wwan_state *info = (void *)&usbnetdev->data;
         sQmiWwanQmap *pQmapDev = (sQmiWwanQmap *)info->unused;
         bridge_mode = pQmapDev->bridge_mode;
     }
  
     return snprintf(buf, PAGE_SIZE, "%u\n", bridge_mode);
 }
  
 static ssize_t bridge_ipv4_show(struct device *dev, struct device_attribute *attr, char *buf) {
     struct net_device *netdev = to_net_dev(dev);
     unsigned int bridge_ipv4 = 0;
     unsigned char ipv4[4];
  
     if (is_qmap_netdev(netdev)) {
         struct qmap_priv *priv = netdev_priv(netdev);
         bridge_ipv4 = priv->bridge_ipv4;    
     }
     else {
         struct usbnet * usbnetdev = netdev_priv( netdev );
         struct qmi_wwan_state *info = (void *)&usbnetdev->data;
         sQmiWwanQmap *pQmapDev = (sQmiWwanQmap *)info->unused;
         bridge_ipv4 = pQmapDev->bridge_ipv4;    
     }
  
     ipv4[0]  = (bridge_ipv4 >> 24) & 0xFF;
     ipv4[1]  = (bridge_ipv4 >> 16) & 0xFF;
     ipv4[2]  = (bridge_ipv4 >> 8) & 0xFF;
     ipv4[3]  = (bridge_ipv4 >> 0) & 0xFF;
     
     return snprintf(buf, PAGE_SIZE, "%d.%d.%d.%d\n",  ipv4[0], ipv4[1], ipv4[2], ipv4[3]);
 }
  
 static ssize_t bridge_ipv4_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) {
     struct net_device *netdev = to_net_dev(dev);
  
     if (is_qmap_netdev(netdev)) {
         struct qmap_priv *priv = netdev_priv(netdev);
         priv->bridge_ipv4 = simple_strtoul(buf, NULL, 16);
     }
     else {
         struct usbnet * usbnetdev = netdev_priv( netdev );
         struct qmi_wwan_state *info = (void *)&usbnetdev->data;
         sQmiWwanQmap *pQmapDev = (sQmiWwanQmap *)info->unused;
         pQmapDev->bridge_ipv4 = simple_strtoul(buf, NULL, 16);
     }
  
     return count;
 }
 #endif
  
 static DEVICE_ATTR(link_state, S_IWUSR | S_IRUGO, link_state_show, link_state_store);
 #ifdef QUECTEL_BRIDGE_MODE
 static DEVICE_ATTR(bridge_mode,  S_IRUGO, bridge_mode_show, NULL);
 static DEVICE_ATTR(bridge_ipv4, S_IWUSR | S_IRUGO, bridge_ipv4_show, bridge_ipv4_store);
 #endif
  
 static struct attribute *qmi_wwan_sysfs_attrs[] = {
     &dev_attr_link_state.attr,
     &dev_attr_qmap_mode.attr,
 #ifdef QUECTEL_BRIDGE_MODE
     &dev_attr_bridge_mode.attr,
     &dev_attr_bridge_ipv4.attr,
 #endif
     NULL,
 };
  
 static struct attribute_group qmi_wwan_sysfs_attr_group = {
     .attrs = qmi_wwan_sysfs_attrs,
 };
  
 #ifdef QUECTEL_BRIDGE_MODE
 static struct attribute *qmi_qmap_sysfs_attrs[] = {
     &dev_attr_bridge_mode.attr,
     &dev_attr_bridge_ipv4.attr,
     NULL,
 };
  
 static struct attribute_group qmi_qmap_sysfs_attr_group = {
     .attrs = qmi_qmap_sysfs_attrs,
 };
 #endif
  
 static int qmap_open(struct net_device *dev)
 {
     struct qmap_priv *priv = netdev_priv(dev);
     struct net_device *real_dev = priv->real_dev;
  
     if (!(priv->real_dev->flags & IFF_UP))
         return -ENETDOWN;
  
     if (netif_carrier_ok(real_dev))
         netif_carrier_on(dev);
     return 0;
 }
  
 static int qmap_stop(struct net_device *pNet)
 {
     netif_carrier_off(pNet);
     return 0;
 }
  
 static int qmap_start_xmit(struct sk_buff *skb, struct net_device *pNet)
 {
     int err;
     struct qmap_priv *priv = netdev_priv(pNet);
     unsigned int len;
     struct qmap_hdr *hdr;
  
     skb_reset_mac_header(skb);
  
 #ifdef QUECTEL_BRIDGE_MODE
     if (priv->bridge_mode && bridge_mode_tx_fixup(pNet, skb, priv->bridge_ipv4, priv->bridge_mac) == NULL) {
           dev_kfree_skb_any (skb);
           return NETDEV_TX_OK;
     }
 #endif
  
     if (skb_pull(skb, ETH_HLEN) == NULL) {
           dev_kfree_skb_any (skb);
           return NETDEV_TX_OK;
        }
    
     len = skb->len;
     hdr = (struct qmap_hdr *)skb_push(skb, sizeof(struct qmap_hdr));
     hdr->cd_rsvd_pad = 0;
     hdr->mux_id = QUECTEL_QMAP_MUX_ID + priv->offset_id;
     hdr->pkt_len = cpu_to_be16(len);
  
     skb->dev = priv->real_dev;
     err = dev_queue_xmit(skb);
     if (err == NET_XMIT_SUCCESS) {
         pNet->stats.tx_packets++;
         pNet->stats.tx_bytes += skb->len;
     } else {
         pNet->stats.tx_errors++;
     }
  
     return err;
 }
  
 static const struct net_device_ops qmap_netdev_ops = {
     .ndo_open       = qmap_open,
     .ndo_stop       = qmap_stop,
     .ndo_start_xmit = qmap_start_xmit,
 };
  
 static int qmap_register_device(sQmiWwanQmap * pDev, u8 offset_id)
 {
     struct net_device *real_dev = pDev->mpNetDev->net;
     struct net_device *qmap_net;
     struct qmap_priv *priv;
     int err;
  
     qmap_net = alloc_etherdev(sizeof(*priv));
     if (!qmap_net)
         return -ENOBUFS;
  
     SET_NETDEV_DEV(qmap_net, &real_dev->dev);
     priv = netdev_priv(qmap_net);
     priv->offset_id = offset_id;
     priv->real_dev = real_dev;
     sprintf(qmap_net->name, "%s.%d", real_dev->name, offset_id + 1);
     qmap_net->netdev_ops = &qmap_netdev_ops;
     memcpy (qmap_net->dev_addr, real_dev->dev_addr, ETH_ALEN);
  
 #ifdef QUECTEL_BRIDGE_MODE
     priv->bridge_mode = !!(pDev->bridge_mode & BIT(offset_id));
     qmap_net->sysfs_groups[0] = &qmi_qmap_sysfs_attr_group;
 #endif
  
     err = register_netdev(qmap_net);
     if (err < 0)
         goto out_free_newdev;
     netif_device_attach (qmap_net);
  
     pDev->mpQmapNetDev[offset_id] = qmap_net;
     qmap_net->flags |= IFF_NOARP;
  
     dev_info(&real_dev->dev, "%s %s\n", __func__, qmap_net->name);
  
     return 0;
  
 out_free_newdev:
     free_netdev(qmap_net);
     return err;
 }
  
 static void qmap_unregister_device(sQmiWwanQmap * pDev, u8 offset_id) {
     struct net_device *net = pDev->mpQmapNetDev[offset_id];
     if (net != NULL) {
         netif_carrier_off( net );
         unregister_netdev (net);
         free_netdev(net);
     }
 }
  
 #ifdef CONFIG_ANDROID
 static int qmap_ndo_do_ioctl(struct net_device *dev,struct ifreq *ifr, int cmd) {
     int rc = -EOPNOTSUPP;
     uint link_state = 0;
  
     switch (cmd) {
     case 0x89F1: //SIOCDEVPRIVATE
         rc = copy_from_user(&link_state, ifr->ifr_ifru.ifru_data, sizeof(link_state));
         if (!rc) {
             char buf[32];
             snprintf(buf, sizeof(buf), "%u", link_state);
             link_state_store(&dev->dev, NULL, buf, strlen(buf));
         }
     break;
  
     default:
     break;
     }
  
     return rc;
 }
 #endif
  
 #ifdef QUECTEL_BRIDGE_MODE
 static int is_qmap_netdev(const struct net_device *netdev) {
     return netdev->netdev_ops == &qmap_netdev_ops;
 }
 #endif
 #endif
  
 static struct sk_buff *qmi_wwan_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags) {
     //MDM9x07,MDM9628,MDM9x40,SDX20,SDX24 only work on RAW IP mode
     if ((dev->driver_info->flags & FLAG_NOARP) == 0)
         return skb;
  
     // Skip Ethernet header from message
     if (dev->net->hard_header_len == 0)
         return skb;
     else
         skb_reset_mac_header(skb);
  
 #ifdef QUECTEL_BRIDGE_MODE
 {
     struct qmi_wwan_state *info = (void *)&dev->data;
     sQmiWwanQmap *pQmapDev = (sQmiWwanQmap *)info->unused;
  
     if (pQmapDev->bridge_mode && bridge_mode_tx_fixup(dev->net, skb, pQmapDev->bridge_ipv4, pQmapDev->bridge_mac) == NULL) {
           dev_kfree_skb_any (skb);
           return NULL;
     }
 }
 #endif
  
     if (skb_pull(skb, ETH_HLEN)) {
         return skb;
     } else {
         dev_err(&dev->intf->dev,  "Packet Dropped ");
     }
  
     // Filter the packet out, release it
     dev_kfree_skb_any(skb);
     return NULL;
 }
 #endif
  
 /* Make up an ethernet header if the packet doesn't have one.
  *
  * A firmware bug common among several devices cause them to send raw
  * IP packets under some circumstances.  There is no way for the
  * driver/host to know when this will happen.  And even when the bug
  * hits, some packets will still arrive with an intact header.
  *
  * The supported devices are only capably of sending IPv4, IPv6 and
  * ARP packets on a point-to-point link. Any packet with an ethernet
  * header will have either our address or a broadcast/multicast
  * address as destination.  ARP packets will always have a header.
  *
  * This means that this function will reliably add the appropriate
  * header iff necessary, provided our hardware address does not start
  * with 4 or 6.
  *
  * Another common firmware bug results in all packets being addressed
  * to 00:a0:c6:00:00:00 despite the host address being different.
  * This function will also fixup such packets.
  */
 static int qmi_wwan_rx_fixup(struct usbnet *dev, struct sk_buff *skb)
 {
     __be16 proto;
 #ifdef QUECTEL_BRIDGE_MODE
     struct qmi_wwan_state *info = (void *)&dev->data;
     sQmiWwanQmap *pQmapDev = (sQmiWwanQmap *)info->unused;
 #endif
     
     /* This check is no longer done by usbnet */
     if (skb->len < dev->net->hard_header_len)
         return 0;
  
     switch (skb->data[0] & 0xf0) {
     case 0x40:
         proto = htons(ETH_P_IP);
         break;
     case 0x60:
         proto = htons(ETH_P_IPV6);
         break;
     case 0x00:
         if (is_multicast_ether_addr(skb->data))
             return 1;
         /* possibly bogus destination - rewrite just in case */
         skb_reset_mac_header(skb);
         goto fix_dest;
     default:
         /* pass along other packets without modifications */
         return 1;
     }
     if (skb_headroom(skb) < ETH_HLEN)
         return 0;
     skb_push(skb, ETH_HLEN);
     skb_reset_mac_header(skb);
     eth_hdr(skb)->h_proto = proto;
     memset(eth_hdr(skb)->h_source, 0, ETH_ALEN);
 #if 1 //Added by Quectel
     //some kernel will drop ethernet packet which's souce mac is all zero
     memcpy(eth_hdr(skb)->h_source, default_modem_addr, ETH_ALEN);
 #endif
 #ifdef QUECTEL_BRIDGE_MODE    
     if (pQmapDev->bridge_mode) {
         memcpy(eth_hdr(skb)->h_dest, pQmapDev->bridge_mac, ETH_ALEN);
     }
 #endif
  
 fix_dest:
     memcpy(eth_hdr(skb)->h_dest, dev->net->dev_addr, ETH_ALEN);
     return 1;
 }
  
 #if defined(QUECTEL_WWAN_QMAP)
 static struct sk_buff *qmap_qmi_wwan_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags) {
     struct qmi_wwan_state *info = (void *)&dev->data;
     sQmiWwanQmap *pQmapDev = (sQmiWwanQmap *)info->unused;
     struct qmap_hdr *qhdr;
  
     if (unlikely(pQmapDev == NULL)) {
         goto drop_skb;
     } else if (unlikely(pQmapDev->qmap_mode && !pQmapDev->link_state)) {
         dev_dbg(&dev->net->dev, "link_state 0x%x, drop skb, len = %u\n", pQmapDev->link_state, skb->len);
         goto drop_skb;
     } else if (pQmapDev->qmap_mode == 0) {
         return qmi_wwan_tx_fixup(dev, skb, flags);
     }
     else if (pQmapDev->qmap_mode > 1) {
         qhdr = (struct qmap_hdr *)skb->data;
         if (qhdr->cd_rsvd_pad != 0) {
             goto drop_skb;
         }
         if ((qhdr->mux_id&0xF0) != 0x80) {
             goto drop_skb;
         }
         return skb;
     }
     else {
         if (qmi_wwan_tx_fixup(dev, skb, flags)) {
             qhdr = (struct qmap_hdr *)skb_push(skb, sizeof(struct qmap_hdr));
             qhdr->cd_rsvd_pad = 0;
             qhdr->mux_id = QUECTEL_QMAP_MUX_ID;
             qhdr->pkt_len = cpu_to_be16(skb->len - sizeof(struct qmap_hdr));
  
                     return skb;
         }
         else {
             return NULL;
         }
     }
  
 drop_skb:
     dev_kfree_skb_any (skb);
     return NULL;
 }
  
 static int qmap_qmi_wwan_rx_fixup(struct usbnet *dev, struct sk_buff *skb)
 {
     struct qmi_wwan_state *info = (void *)&dev->data;
     sQmiWwanQmap *pQmapDev = (sQmiWwanQmap *)info->unused;
     static int debug_len = 0;
     int debug_pkts = 0;
     int update_len = skb->len;
  
     if (pQmapDev->qmap_mode == 0)
         return qmi_wwan_rx_fixup(dev, skb);
  
     while (skb->len > sizeof(struct qmap_hdr)) {
         struct qmap_hdr *qhdr = (struct qmap_hdr *)skb->data;
         struct net_device *qmap_net;
         struct sk_buff *qmap_skb;
 #ifdef QUECTEL_BRIDGE_MODE
         uint bridge_mode = 0;
         unsigned char *bridge_mac;
 #endif
         __be16 proto;
         int pkt_len;
         u8 offset_id = 0;
         int err;
         unsigned len = (be16_to_cpu(qhdr->pkt_len) + sizeof(struct qmap_hdr));
  
         if (skb->len < (be16_to_cpu(qhdr->pkt_len) + sizeof(struct qmap_hdr))) {
             dev_info(&dev->net->dev, "drop qmap unknow pkt, len=%d, pkt_len=%d\n", skb->len, be16_to_cpu(qhdr->pkt_len));
             goto out;
         }
  
         debug_pkts++;
  
         if (qhdr->cd_rsvd_pad & 0x80) {
             dev_info(&dev->net->dev, "drop qmap command packet %x\n", qhdr->cd_rsvd_pad);
             goto skip_pkt;;
         }
  
         offset_id = qhdr->mux_id - QUECTEL_QMAP_MUX_ID;
         if (offset_id >= pQmapDev->qmap_mode) {
             dev_info(&dev->net->dev, "drop qmap unknow mux_id %x\n", qhdr->mux_id);
             goto skip_pkt;
         }
  
         qmap_net = pQmapDev->mpQmapNetDev[offset_id];
  
         if (qmap_net == NULL) {
             dev_info(&dev->net->dev, "drop qmap unknow mux_id %x\n", qhdr->mux_id);
             goto skip_pkt;
         }
  
         switch (skb->data[sizeof(struct qmap_hdr)] & 0xf0) {
             case 0x40:
                 proto = htons(ETH_P_IP);
             break;
             case 0x60:
                 proto = htons(ETH_P_IPV6);
             break;
             default:
                 goto skip_pkt;
         }
  
         pkt_len = be16_to_cpu(qhdr->pkt_len) - (qhdr->cd_rsvd_pad&0x3F);
         qmap_skb = netdev_alloc_skb(qmap_net, ETH_HLEN + pkt_len);
         if (qmap_skb == NULL) {
             dev_info(&dev->net->dev, "fail to alloc skb, pkt_len = %d\n", pkt_len);
             return 0;
         }
  
         skb_reset_mac_header(qmap_skb);
         memcpy(eth_hdr(qmap_skb)->h_source, default_modem_addr, ETH_ALEN);
         memcpy(eth_hdr(qmap_skb)->h_dest, qmap_net->dev_addr, ETH_ALEN);
         eth_hdr(qmap_skb)->h_proto = proto;        
         memcpy(skb_put(qmap_skb, ETH_HLEN + pkt_len) + ETH_HLEN, skb->data + sizeof(struct qmap_hdr), pkt_len);
 #ifdef QUECTEL_BRIDGE_MODE
         if (pQmapDev->qmap_mode > 1) {
             struct qmap_priv *priv = netdev_priv(qmap_net);
             bridge_mode = priv->bridge_mode;
             bridge_mac = priv->bridge_mac;
         }
         else {
             bridge_mode = pQmapDev->bridge_mode;
             bridge_mac = pQmapDev->bridge_mac;
         }
             if (bridge_mode) {
                 memcpy(eth_hdr(qmap_skb)->h_dest, bridge_mac, ETH_ALEN);
             }
 #endif
  
         if (pQmapDev->qmap_mode > 1) {
             qmap_skb->protocol = eth_type_trans (qmap_skb, qmap_net);
             memset(qmap_skb->cb, 0, sizeof(struct skb_data));
             err = netif_rx(qmap_skb);
             if (err == NET_RX_SUCCESS) {
                 qmap_net->stats.rx_packets++;
                 qmap_net->stats.rx_bytes += qmap_skb->len;
             } else {
                 qmap_net->stats.rx_errors++;
             }
         }
         else {
             usbnet_skb_return(dev, qmap_skb);
         }
  
         skip_pkt:
         skb_pull(skb, len);
     }
  
 out:
     if (update_len > debug_len) {
         debug_len = update_len;
         dev_info(&dev->net->dev, "rx_pkts=%d, rx_len=%d\n", debug_pkts, debug_len);
     }
     
     return 0;
 }
 #endif
  
 /* very simplistic detection of IPv4 or IPv6 headers */
 static bool possibly_iphdr(const char *data)
 {
     return (data[0] & 0xd0) == 0x40;
 }
  
 /* disallow addresses which may be confused with IP headers */
 static int qmi_wwan_mac_addr(struct net_device *dev, void *p)
 {
     int ret;
     struct sockaddr *addr = p;
  
     ret = eth_prepare_mac_addr_change(dev, p);
     if (ret < 0)
         return ret;
     if (possibly_iphdr(addr->sa_data))
         return -EADDRNOTAVAIL;
     eth_commit_mac_addr_change(dev, p);
     return 0;
 }
  
 static const struct net_device_ops qmi_wwan_netdev_ops = {
     .ndo_open        = usbnet_open,
     .ndo_stop        = usbnet_stop,
     .ndo_start_xmit        = usbnet_start_xmit,
     .ndo_tx_timeout        = usbnet_tx_timeout,
     .ndo_change_mtu        = usbnet_change_mtu,
     .ndo_set_mac_address    = qmi_wwan_mac_addr,
     .ndo_validate_addr    = eth_validate_addr,
 #if defined(QUECTEL_WWAN_QMAP) && defined(CONFIG_ANDROID)
     .ndo_do_ioctl = qmap_ndo_do_ioctl,
 #endif
 };
  
 /* using a counter to merge subdriver requests with our own into a
  * combined state
  */
 static int qmi_wwan_manage_power(struct usbnet *dev, int on)
 {
     struct qmi_wwan_state *info = (void *)&dev->data;
     int rv;
  
     dev_dbg(&dev->intf->dev, "%s() pmcount=%d, on=%d\n", __func__,
         atomic_read(&info->pmcount), on);
  
     if ((on && atomic_add_return(1, &info->pmcount) == 1) ||
         (!on && atomic_dec_and_test(&info->pmcount))) {
         /* need autopm_get/put here to ensure the usbcore sees
          * the new value
          */
         rv = usb_autopm_get_interface(dev->intf);
         dev->intf->needs_remote_wakeup = on;
         if (!rv)
             usb_autopm_put_interface(dev->intf);
     }
     return 0;
 }
  
 static int qmi_wwan_cdc_wdm_manage_power(struct usb_interface *intf, int on)
 {
     struct usbnet *dev = usb_get_intfdata(intf);
  
     /* can be called while disconnecting */
     if (!dev)
         return 0;
     return qmi_wwan_manage_power(dev, on);
 }
  
 /* collect all three endpoints and register subdriver */
 static int qmi_wwan_register_subdriver(struct usbnet *dev)
 {
     int rv;
     struct usb_driver *subdriver = NULL;
     struct qmi_wwan_state *info = (void *)&dev->data;
  
     /* collect bulk endpoints */
     rv = usbnet_get_endpoints(dev, info->data);
     if (rv < 0)
         goto err;
  
     /* update status endpoint if separate control interface */
     if (info->control != info->data)
         dev->status = &info->control->cur_altsetting->endpoint[0];
  
     /* require interrupt endpoint for subdriver */
     if (!dev->status) {
         rv = -EINVAL;
         goto err;
     }
  
     /* for subdriver power management */
     atomic_set(&info->pmcount, 0);
  
     /* register subdriver */
     subdriver = usb_cdc_wdm_register(info->control, &dev->status->desc,
                      4096, &qmi_wwan_cdc_wdm_manage_power);
     if (IS_ERR(subdriver)) {
         dev_err(&info->control->dev, "subdriver registration failed\n");
         rv = PTR_ERR(subdriver);
         goto err;
     }
  
     /* prevent usbnet from using status endpoint */
     dev->status = NULL;
  
     /* save subdriver struct for suspend/resume wrappers */
     info->subdriver = subdriver;
  
 err:
     return rv;
 }
  
 static int qmi_wwan_bind(struct usbnet *dev, struct usb_interface *intf)
 {
     int status = -1;
     u8 *buf = intf->cur_altsetting->extra;
     int len = intf->cur_altsetting->extralen;
     struct usb_interface_descriptor *desc = &intf->cur_altsetting->desc;
     struct usb_cdc_union_desc *cdc_union = NULL;
     struct usb_cdc_ether_desc *cdc_ether = NULL;
     u32 found = 0;
     struct usb_driver *driver = driver_of(intf);
     struct qmi_wwan_state *info = (void *)&dev->data;
  
     BUILD_BUG_ON((sizeof(((struct usbnet *)0)->data) <
               sizeof(struct qmi_wwan_state)));
  
     /* set up initial state */
     info->control = intf;
     info->data = intf;
  
     /* and a number of CDC descriptors */
     while (len > 3) {
         struct usb_descriptor_header *h = (void *)buf;
  
         /* ignore any misplaced descriptors */
         if (h->bDescriptorType != USB_DT_CS_INTERFACE)
             goto next_desc;
  
         /* buf[2] is CDC descriptor subtype */
         switch (buf[2]) {
         case USB_CDC_HEADER_TYPE:
             if (found & 1 << USB_CDC_HEADER_TYPE) {
                 dev_dbg(&intf->dev, "extra CDC header\n");
                 goto err;
             }
             if (h->bLength != sizeof(struct usb_cdc_header_desc)) {
                 dev_dbg(&intf->dev, "CDC header len %u\n",
                     h->bLength);
                 goto err;
             }
             break;
         case USB_CDC_UNION_TYPE:
             if (found & 1 << USB_CDC_UNION_TYPE) {
                 dev_dbg(&intf->dev, "extra CDC union\n");
                 goto err;
             }
             if (h->bLength != sizeof(struct usb_cdc_union_desc)) {
                 dev_dbg(&intf->dev, "CDC union len %u\n",
                     h->bLength);
                 goto err;
             }
             cdc_union = (struct usb_cdc_union_desc *)buf;
             break;
         case USB_CDC_ETHERNET_TYPE:
             if (found & 1 << USB_CDC_ETHERNET_TYPE) {
                 dev_dbg(&intf->dev, "extra CDC ether\n");
                 goto err;
             }
             if (h->bLength != sizeof(struct usb_cdc_ether_desc)) {
                 dev_dbg(&intf->dev, "CDC ether len %u\n",
                     h->bLength);
                 goto err;
             }
             cdc_ether = (struct usb_cdc_ether_desc *)buf;
             break;
         }
  
         /* Remember which CDC functional descriptors we've seen.  Works
          * for all types we care about, of which USB_CDC_ETHERNET_TYPE
          * (0x0f) is the highest numbered
          */
         if (buf[2] < 32)
             found |= 1 << buf[2];
  
 next_desc:
         len -= h->bLength;
         buf += h->bLength;
     }
  
     /* Use separate control and data interfaces if we found a CDC Union */
     if (cdc_union) {
         info->data = usb_ifnum_to_if(dev->udev,
                          cdc_union->bSlaveInterface0);
         if (desc->bInterfaceNumber != cdc_union->bMasterInterface0 ||
             !info->data) {
             dev_err(&intf->dev,
                 "bogus CDC Union: master=%u, slave=%u\n",
                 cdc_union->bMasterInterface0,
                 cdc_union->bSlaveInterface0);
             goto err;
         }
     }
  
     /* errors aren't fatal - we can live with the dynamic address */
     if (cdc_ether) {
         dev->hard_mtu = le16_to_cpu(cdc_ether->wMaxSegmentSize);
         usbnet_get_ethernet_addr(dev, cdc_ether->iMACAddress);
     }
  
     /* claim data interface and set it up */
     if (info->control != info->data) {
         status = usb_driver_claim_interface(driver, info->data, dev);
         if (status < 0)
             goto err;
     }
  
     status = qmi_wwan_register_subdriver(dev);
     if (status < 0 && info->control != info->data) {
         usb_set_intfdata(info->data, NULL);
         usb_driver_release_interface(driver, info->data);
     }
  
     /* Never use the same address on both ends of the link, even
      * if the buggy firmware told us to.
      */
     if (ether_addr_equal(dev->net->dev_addr, default_modem_addr))
         eth_hw_addr_random(dev->net);
  
     /* make MAC addr easily distinguishable from an IP header */
     if (possibly_iphdr(dev->net->dev_addr)) {
         dev->net->dev_addr[0] |= 0x02;    /* set local assignment bit */
         dev->net->dev_addr[0] &= 0xbf;    /* clear "IP" bit */
     }
     dev->net->netdev_ops = &qmi_wwan_netdev_ops;
  
 #if 1 //Added by Quectel
     if (dev->driver_info->flags & FLAG_NOARP) {        
         dev_info(&intf->dev, "Quectel EC25&EC21&EG91&EG95&EG06&EP06&EM06&EG12&EP12&EM12&EG16&EG18&BG96&AG35 work on RawIP mode\n");
         dev->net->flags |= IFF_NOARP;
         usb_control_msg(
             interface_to_usbdev(intf),
             usb_sndctrlpipe(interface_to_usbdev(intf), 0),
             0x22, //USB_CDC_REQ_SET_CONTROL_LINE_STATE
             0x21, //USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE
             1, //active CDC DTR
             intf->cur_altsetting->desc.bInterfaceNumber,
             NULL, 0, 100);
     }
  
     //to advoid module report mtu 1460, but rx 1500 bytes IP packets, and cause the customer's system crash
     //next setting can make usbnet.c:usbnet_change_mtu() do not modify rx_urb_size according to hard mtu
     dev->rx_urb_size = ETH_DATA_LEN + ETH_HLEN + 6;
  
 #if defined(QUECTEL_WWAN_QMAP)
     if (qmap_mode > QUECTEL_WWAN_QMAP)
         qmap_mode = QUECTEL_WWAN_QMAP;
  
     if (!status)
     {
         sQmiWwanQmap *pQmapDev = (sQmiWwanQmap *)kzalloc(sizeof(sQmiWwanQmap), GFP_KERNEL);
  
         if (pQmapDev == NULL)
             return -ENODEV;
  
 #ifdef QUECTEL_BRIDGE_MODE
         pQmapDev->bridge_mode = bridge_mode;
 #endif
         pQmapDev->mpNetDev = dev;
         pQmapDev->link_state = 1;
         
         if (dev->driver_info->flags & FLAG_NOARP)
         {
             int idProduct = le16_to_cpu(dev->udev->descriptor.idProduct);
             int lte_a = (idProduct == 0x0306 || idProduct == 0x0512 || idProduct == 0x0620 || idProduct == 0x0800);
  
             pQmapDev->qmap_mode = qmap_mode;
             if (lte_a || dev->udev->speed == USB_SPEED_SUPER) {
                 if (pQmapDev->qmap_mode == 0) {
                     pQmapDev->qmap_mode = 1; //force use QMAP
                     if(qmap_mode == 0)
                         qmap_mode = 1; //old quectel-CM only check sys/module/wwan0/parameters/qmap_mode
                 }
             }
  
             if (pQmapDev->qmap_mode) {
                 if (idProduct == 0x0121 || idProduct == 0x0125 || idProduct == 0x0435) //MDM9x07
                     dev->rx_urb_size = 4*1024;
                 else if (lte_a || dev->udev->speed == USB_SPEED_SUPER)
                     dev->rx_urb_size = 32*1024;
                 else
                     dev->rx_urb_size = 32*1024;
  
                 //for these modules, if send pakcet before qmi_start_network, or cause host PC crash, or cause modules crash
                 if (lte_a || dev->udev->speed == USB_SPEED_SUPER)
                     pQmapDev->link_state = 0;
             }
         }
  
         info->unused = (unsigned long)pQmapDev;        
         dev->net->sysfs_groups[0] = &qmi_wwan_sysfs_attr_group;
  
         dev_info(&intf->dev, "rx_urb_size = %zd\n", dev->rx_urb_size);
     }
 #endif
 #endif
  
 err:
     return status;
 }
  
 static void qmi_wwan_unbind(struct usbnet *dev, struct usb_interface *intf)
 {
     struct qmi_wwan_state *info = (void *)&dev->data;
     struct usb_driver *driver = driver_of(intf);
     struct usb_interface *other;
  
     if (info->subdriver && info->subdriver->disconnect)
         info->subdriver->disconnect(info->control);
  
     /* allow user to unbind using either control or data */
     if (intf == info->control)
         other = info->data;
     else
         other = info->control;
  
     /* only if not shared */
     if (other && intf != other) {
         usb_set_intfdata(other, NULL);
         usb_driver_release_interface(driver, other);
     }
  
     info->subdriver = NULL;
     info->data = NULL;
     info->control = NULL;
 }
  
 /* suspend/resume wrappers calling both usbnet and the cdc-wdm
  * subdriver if present.
  *
  * NOTE: cdc-wdm also supports pre/post_reset, but we cannot provide
  * wrappers for those without adding usbnet reset support first.
  */
 static int qmi_wwan_suspend(struct usb_interface *intf, pm_message_t message)
 {
     struct usbnet *dev = usb_get_intfdata(intf);
     struct qmi_wwan_state *info = (void *)&dev->data;
     int ret;
  
     /* Both usbnet_suspend() and subdriver->suspend() MUST return 0
      * in system sleep context, otherwise, the resume callback has
      * to recover device from previous suspend failure.
      */
     ret = usbnet_suspend(intf, message);
     if (ret < 0)
         goto err;
  
     if (intf == info->control && info->subdriver &&
         info->subdriver->suspend)
         ret = info->subdriver->suspend(intf, message);
     if (ret < 0)
         usbnet_resume(intf);
 err:
     return ret;
 }
  
 static int qmi_wwan_resume(struct usb_interface *intf)
 {
     struct usbnet *dev = usb_get_intfdata(intf);
     struct qmi_wwan_state *info = (void *)&dev->data;
     int ret = 0;
     bool callsub = (intf == info->control && info->subdriver &&
             info->subdriver->resume);
  
     if (callsub)
         ret = info->subdriver->resume(intf);
     if (ret < 0)
         goto err;
     ret = usbnet_resume(intf);
     if (ret < 0 && callsub)
         info->subdriver->suspend(intf, PMSG_SUSPEND);
 err:
     return ret;
 }
  
 static int qmi_wwan_reset_resume(struct usb_interface *intf)
 {
     dev_info(&intf->dev, "device do not support reset_resume\n");
     intf->needs_binding = 1;
     return -EOPNOTSUPP;
 }
  
 static const struct driver_info    qmi_wwan_info = {
     .description    = "WWAN/QMI device",
     .flags        = FLAG_WWAN,
     .bind        = qmi_wwan_bind,
     .unbind        = qmi_wwan_unbind,
     .manage_power    = qmi_wwan_manage_power,
     .rx_fixup       = qmi_wwan_rx_fixup,
 };
  
 static const struct driver_info qmi_wwan_raw_ip_info = {
     .description    = "WWAN/QMI device",
     .flags        = FLAG_WWAN | FLAG_RX_ASSEMBLE | FLAG_NOARP | FLAG_SEND_ZLP,
     .bind        = qmi_wwan_bind,
     .unbind        = qmi_wwan_unbind,
     .manage_power    = qmi_wwan_manage_power,
 #if defined(QUECTEL_WWAN_QMAP)
     .tx_fixup       = qmap_qmi_wwan_tx_fixup,
     .rx_fixup       = qmap_qmi_wwan_rx_fixup,
 #else
     .tx_fixup       = qmi_wwan_tx_fixup,
     .rx_fixup       = qmi_wwan_rx_fixup,
 #endif
 };
  
  
 /* map QMI/wwan function by a fixed interface number */
 #define QMI_FIXED_INTF(vend, prod, num) \
     USB_DEVICE_INTERFACE_NUMBER(vend, prod, num), \
     .driver_info = (unsigned long)&qmi_wwan_info
  
 #define QMI_FIXED_RAWIP_INTF(vend, prod, num) \
     USB_DEVICE_INTERFACE_NUMBER(vend, prod, num), \
     .driver_info = (unsigned long)&qmi_wwan_raw_ip_info
  
 static const struct usb_device_id products[] = {
 #if 1 //Added by Quectel
     { QMI_FIXED_INTF(0x05C6, 0x9003, 4) },  /* Quectel UC20 */
     { QMI_FIXED_INTF(0x05C6, 0x9215, 4) },  /* Quectel EC20 (MDM9215) */
     { QMI_FIXED_RAWIP_INTF(0x2C7C, 0x0125, 4) },  /* Quectel EC20 (MDM9X07)/EC25/EG25 */
     { QMI_FIXED_RAWIP_INTF(0x2C7C, 0x0121, 4) },  /* Quectel EC21 */
     { QMI_FIXED_RAWIP_INTF(0x2C7C, 0x0191, 4) },  /* Quectel EG91 */
     { QMI_FIXED_RAWIP_INTF(0x2C7C, 0x0195, 4) },  /* Quectel EG95 */
     { QMI_FIXED_RAWIP_INTF(0x2C7C, 0x0306, 4) },  /* Quectel EG06/EP06/EM06 */
     { QMI_FIXED_RAWIP_INTF(0x2C7C, 0x0512, 4) },  /* Quectel EG12/EP12/EM12/EG16/EG18 */
     { QMI_FIXED_RAWIP_INTF(0x2C7C, 0x0296, 4) },  /* Quectel BG96 */
     { QMI_FIXED_RAWIP_INTF(0x2C7C, 0x0435, 4) },  /* Quectel AG35 */
     { QMI_FIXED_RAWIP_INTF(0x2C7C, 0x0620, 4) },  /* Quectel EG20 */
     { QMI_FIXED_RAWIP_INTF(0x2C7C, 0x0800, 4) },  /* Quectel RG500 */
 #endif
     { }                    /* END */
 };
 MODULE_DEVICE_TABLE(usb, products);
  
 static int qmi_wwan_probe(struct usb_interface *intf,
               const struct usb_device_id *prod)
 {
     struct usb_device_id *id = (struct usb_device_id *)prod;
  
     /* Workaround to enable dynamic IDs.  This disables usbnet
      * blacklisting functionality.  Which, if required, can be
      * reimplemented here by using a magic "blacklist" value
      * instead of 0 in the static device id table
      */
     if (!id->driver_info) {
         dev_dbg(&intf->dev, "setting defaults for dynamic device id\n");
         id->driver_info = (unsigned long)&qmi_wwan_info;
     }
  
     if (intf->cur_altsetting->desc.bInterfaceClass != 0xff) {
         dev_info(&intf->dev,  "Quectel module not qmi_wwan mode! please check 'at+qcfg=\"usbnet\"'\n");
         return -ENODEV;
     }
  
     return usbnet_probe(intf, id);
 }
  
 #if defined(QUECTEL_WWAN_QMAP)
 static int qmap_qmi_wwan_probe(struct usb_interface *intf,
               const struct usb_device_id *prod)
 {
     int status = qmi_wwan_probe(intf, prod);
     
     if (!status) {
         struct usbnet *dev = usb_get_intfdata(intf);
         struct qmi_wwan_state *info = (void *)&dev->data;        
         sQmiWwanQmap *pQmapDev = (sQmiWwanQmap *)info->unused;
         unsigned i;
  
         if (pQmapDev) {
             if (pQmapDev->qmap_mode == 1) {
                 pQmapDev->mpQmapNetDev[0] = dev->net;
             }
             else if (pQmapDev->qmap_mode > 1) {
                 for (i = 0; i < pQmapDev->qmap_mode; i++) {
                     qmap_register_device(pQmapDev, i);
                 }
             }
         }
     }
  
     return status;
 }
  
 static void qmap_qmi_wwan_disconnect(struct usb_interface *intf)
 {
     struct usbnet *dev = usb_get_intfdata(intf);
     struct qmi_wwan_state *info = (void *)&dev->data;
     sQmiWwanQmap *pQmapDev = (sQmiWwanQmap *)info->unused;
  
     if (pQmapDev) {
         if (pQmapDev->qmap_mode > 1) {
             unsigned i;
  
             for (i = 0; i < pQmapDev->qmap_mode; i++) {
                 qmap_unregister_device(pQmapDev, i);
             }    
         }
         
         kfree(pQmapDev);
     }
  
     usbnet_disconnect(intf);
 }
 #endif
  
 static struct usb_driver qmi_wwan_driver = {
     .name              = "qmi_wwan_q",
     .id_table          = products,
     .probe              = qmi_wwan_probe,
 #if defined(QUECTEL_WWAN_QMAP)
     .probe              = qmap_qmi_wwan_probe,
     .disconnect          = qmap_qmi_wwan_disconnect,
 #else
     .probe              = qmi_wwan_probe,
     .disconnect          = usbnet_disconnect,
 #endif
     .suspend          = qmi_wwan_suspend,
     .resume              =    qmi_wwan_resume,
     .reset_resume         = qmi_wwan_reset_resume,
     .supports_autosuspend = 1,
     .disable_hub_initiated_lpm = 1,
 };
  
 module_usb_driver(qmi_wwan_driver);
  
 MODULE_AUTHOR("Bjørn Mork <bjorn@mork.no>");
 MODULE_DESCRIPTION("Qualcomm MSM Interface (QMI) WWAN driver");
 MODULE_LICENSE("GPL");
 #define QUECTEL_WWAN_VERSION "Quectel_Linux&Android_QMI_WWAN_Driver_V1.1"
 MODULE_VERSION(QUECTEL_WWAN_VERSION);
  
 8、
 Z:\rk3399-android-11\kernel\drivers\usb\serial\option.c
static int option_probe(struct usb_serial *serial,
             const struct usb_device_id *id)
 {
     struct usb_interface_descriptor *iface_desc =
                 &serial->interface->cur_altsetting->desc;
     unsigned long device_flags = id->driver_info;
    /*simcom*/
     if(serial->dev->descriptor.idVendor == SIMCOM_PRODUCT_VID_1E0E && 
        serial->dev->descriptor.idProduct == SIMCOM_PRODUCT_PID_9001 && 
        serial->interface->cur_altsetting->desc.bInterfaceNumber >= 4)
         return -ENODEV;
    printk("idVendor:%x,idProduct:%x,bInterfaceNumber:%d\n",serial->dev->descriptor.idVendor,serial->dev->descriptor.idProduct,serial->interface->cur_altsetting->desc.bInterfaceNumber);
     if (serial->dev->descriptor.idVendor == QUECTEL_VENDOR_ID && 
             serial->dev->descriptor.idProduct == QUECTEL_PRODUCT_EC25 &&
         serial->interface->cur_altsetting->desc.bInterfaceNumber >= 4)
         return -ENODEV;
printk("ckkkkkkkkkk\n");
    /* Never bind to the CD-Rom emulation interface    */
     if (iface_desc->bInterfaceClass == USB_CLASS_MASS_STORAGE)
         return -ENODEV;
    /*
      * Don't bind reserved interfaces (like network ones) which often have
      * the same class/subclass/protocol as the serial interfaces.  Look at
      * the Windows driver .INF files for reserved interface numbers.
      */
     if (iface_is_reserved(device_flags, iface_desc->bInterfaceNumber))
         return -ENODEV;
    /*
      * Allow matching on bNumEndpoints for devices whose interface numbers
      * can change (e.g. Quectel EP06).
      */
     if (device_flags & NUMEP2 && iface_desc->bNumEndpoints != 2)
         return -ENODEV;
    /* Store the device flags so we can use them during attach. */
     usb_set_serial_data(serial, (void *)device_flags);
    return 0;
 }
【几乎没有改动】
 Z:\rk3399-android-11\kernel\drivers\usb\serial\qcserial.c
 Z:\rk3399-android-11\kernel\drivers\usb\serial\usb_wwan.c
static struct urb *usb_wwan_setup_urb(struct usb_serial_port *port,
                       int endpoint,
                       int dir, void *ctx, char *buf, int len,
                       void (*callback) (struct urb *))
 {
     struct usb_serial *serial = port->serial;
     struct usb_wwan_intf_private *intfdata = usb_get_serial_data(serial);
     struct urb *urb;
     struct usb_device_descriptor *desc = &serial->dev->descriptor;
    urb = usb_alloc_urb(0, GFP_KERNEL);    /* No ISO */
     if (!urb)
         return NULL;
    usb_fill_bulk_urb(urb, serial->dev,
               usb_sndbulkpipe(serial->dev, endpoint) | dir,
               buf, len, callback, ctx);
    if (intfdata->use_zlp && dir == USB_DIR_OUT)
         urb->transfer_flags |= URB_ZERO_PACKET;
    if (dir == USB_DIR_OUT) {
        if ((desc->idVendor == cpu_to_le16(0x1286) &&
              desc->idProduct == cpu_to_le16(0x4e3c)))
             urb->transfer_flags |= URB_ZERO_PACKET;
         if (desc->idVendor == cpu_to_le16(0x2c7c))
             urb->transfer_flags |= URB_ZERO_PACKET;    
     }
     return urb;
 }
修改为:
 static struct urb *usb_wwan_setup_urb(struct usb_serial_port *port,
                       int endpoint,
                       int dir, void *ctx, char *buf, int len,
                       void (*callback) (struct urb *))
 {
     struct usb_serial *serial = port->serial;
     struct usb_wwan_intf_private *intfdata = usb_get_serial_data(serial);
     struct urb *urb;
     struct usb_device_descriptor *desc = &serial->dev->descriptor;
    urb = usb_alloc_urb(0, GFP_KERNEL);    /* No ISO */
     if (!urb)
         return NULL;
    usb_fill_bulk_urb(urb, serial->dev,
               usb_sndbulkpipe(serial->dev, endpoint) | dir,
               buf, len, callback, ctx);
    if (intfdata->use_zlp && dir == USB_DIR_OUT)
         urb->transfer_flags |= URB_ZERO_PACKET;
    if (dir == USB_DIR_OUT) {
#define DEV_MATCH(udesc, vid, pid) \
     (udesc->idVendor == cpu_to_le16(vid) && desc->idProduct == cpu_to_le16(pid))
         if (DEV_MATCH(desc, 0x1286, 0x4e3c) ||
             DEV_MATCH(desc, 0x05C6, 0x9090) ||
             DEV_MATCH(desc, 0x05C6, 0x9003) ||
             DEV_MATCH(desc, 0x05C6, 0x9215) ||
             (desc->idVendor == cpu_to_le16(0x2C7C)))
             urb->transfer_flags |= URB_ZERO_PACKET;
 #undef DEV_MATCH
     }
    return urb;
 }

 9、
 Z:\rk3399-android-11\system\core\init\devices.cpp
 void DeviceHandler::HandleUevent(const Uevent& uevent) {
     if (uevent.action == "add" || uevent.action == "change" || uevent.action == "online") {
         FixupSysPermissions(uevent.path, uevent.subsystem);
     }
    // if it's not a /dev device, nothing to do
     if (uevent.major < 0 || uevent.minor < 0) return;
    std::string devpath;
     std::vector<std::string> links;
     bool block = false;
    if (uevent.subsystem == "block") {
         block = true;
         devpath = "/dev/block/" + Basename(uevent.path);
        if (StartsWith(uevent.path, "/devices")) {
             links = GetBlockDeviceSymlinks(uevent);
         }
     } else if (const auto subsystem =
                    std::find(subsystems_.cbegin(), subsystems_.cend(), uevent.subsystem);
                subsystem != subsystems_.cend()) {
         devpath = subsystem->ParseDevPath(uevent);
     } else if (uevent.subsystem == "usb") {
         if (!uevent.device_name.empty()) {
             devpath = "/dev/" + uevent.device_name;
         } else {
             // This imitates the file system that would be created
             // if we were using devfs instead.
             // Minors are broken up into groups of 128, starting at "001"
             int bus_id = uevent.minor / 128 + 1;
             int device_id = uevent.minor % 128 + 1;
             devpath = StringPrintf("/dev/bus/usb/%03d/%03d", bus_id, device_id);
         }
    // add by quectel for mknod /dev/cdc-wdm0
     } else if (uevent.subsystem == "usbmisc" && !uevent.device_name.empty()) {
         devpath = "/dev/" + uevent.device_name;
    } else if (uevent.subsystem == "usbmisc" && !uevent.device_name.empty()) {
            devpath = "/dev/" + uevent.device_name;
            
            //PLOG(ERROR) << "Failed to symlink " << devpath << " to " << link << ", which already links to: " << link_path;
            PLOG(ERROR) << "2024/1/5 22:56 wenyuanbo " << devpath ;
     } else if (StartsWith(uevent.subsystem, "usb")) {
         // ignore other USB events
         return;
     } else {
         devpath = "/dev/" + Basename(uevent.path);
     }
mkdir_recursive(Dirname(devpath), 0755);
HandleDevice(uevent.action, devpath, block, uevent.major, uevent.minor, links);
    // Duplicate /dev/ashmem device and name it /dev/ashmem<boot_id>.
     // TODO(b/111903542): remove once all users of /dev/ashmem are migrated to libcutils API.
     HandleAshmemUevent(uevent);
 }

 参考资料:
 https://download.csdn.net/download/seasonfangjing/86247556
 RK356X android11 移远EC20 modem支持
对应工程设置BOARD_HAS_EC20_MODEM := true
device/rockchip/rk356x/itx68/BoardConfig.mk
 BOARD_HAS_EC20_MODEM := true
system/core/init
 diff --git a/init/devices.cpp b/init/devices.cpp
 index 9fbec641b..e3c823d05 100644
 --- a/init/devices.cpp
 +++ b/init/devices.cpp
 @@ -492,7 +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);
          }
 -    } else if (StartsWith(uevent.subsystem, "usb")) {
 +    } else if (uevent.subsystem == "usbmisc" && !uevent.device_name.empty()) {
 +           devpath = "/dev/" + uevent.device_name;
 +    }
 +     else if (StartsWith(uevent.subsystem, "usb")) {
          // ignore other USB events
          return;
      } else {
device/rockchip
 --- a/overlay/frameworks/base/core/res/res/values/config.xml
 +++ b/overlay/frameworks/base/core/res/res/values/config.xml
 @@ -31,6 +31,14 @@
      <!-- 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,true"</item>
 +        <item>"mobile_supl,3,0,2,60000,true"</item>
 +        <item>"mobile_dun,4,0,2,60000,true"</item>
 +        <item>"mobile_hipri,5,0,3,60000,true"</item>
 +        <item>"mobile_fota,10,0,2,60000,true"</item>
 +        <item>"mobile_ims,11,0,2,60000,true"</item>
 +        <item>"mobile_cbs,12,0,2,60000,true"</item>
          <item>"bluetooth,7,7,0,-1,true"</item>


 【可选参考】
 https://blog.csdn.net/longmin96/article/details/122687865
 RK3568-ANDROID11-4G-EC20-系统篇(移远模块)
【可选参考,需要会员下载库文件】
 https://blog.csdn.net/yjz_0314/article/details/134142847
 Android11.0系统中适配EC20模块4G及GPS功能



 参考资料:
 http://www.friendlyelec.com.cn/agent.asp
 http://www.friendlyelec.com.cn/
 https://download.friendlyelec.com/NanoPC-T4
 https://wiki.friendlyelec.com/wiki/index.php/NanoPC-T4/zh#.E4.B8.8B.E8.BD.BDAndroid10.E6.BA.90.E4.BB.A3.E7.A0.81
 https://item.taobao.com/item.htm?spm=a1z09.2.0.0.37562e8dcotDm6&id=570312633249&_u=7ju3ku004a
 友善NanoPC-T4瑞芯微RK3399开发板ROS双摄4K播放开源AI智能安卓10
WiKi维基教程(固件介绍,使用说明,操作步骤等)
 http://wiki.friendlyelec.com/wiki/index.php/NanoPC-T4
 系统固件下载
 https://dl.friendlyelec.com/nanopct4
 原理图(pdf格式)
 http://wiki.friendlyelec.com/wiki/images/e/e0/NanoPC-T4-1902-Schematic.pdf
 尺寸图(dxf格式)
 http://wiki.friendlyelec.com/wiki/images/b/bc/NanoPC-T4_1802_Drawing%28dxf%29.zip
 http://www.friendlyelec.com.cn/nanopi-m4.asp
 NanoPi M4 | NanoPi M4V2
https://wiki.friendlyelec.com/wiki/index.php/NanoPi_M4/zh
 15.3 编译Android10源代码
 15.3.1 下载Android10源代码
 有以下两种途径获取 Android10 的源代码,都需要联网:
使用网盘里的git repo压缩包
 网盘下载地址: 点击进入
https://download.friendlyelec.com/NanoPiM4
 https://pan.baidu.com/share/init?surl=oBLn9H31hILJKEPQXgrUog
 提取码:yn6r



















