Android platform USB WiFi drive porting and usage

A. Android platform WiFi Basic code path

1. wpa_supplicant Source Section

external/wpa_supplicant_6/

Build library libwpa_client.so and daemon wpa_supplicant

2. WiFi HAL Layer Code

Located in hardware/libhardware_legary/wifi/

3. The JNI part of WiFi

Located in Frameworks/base/core/jni/android_net_wifi_wifi.cpp

4. Java section

Located in frameworks/base/services/java/com/android/server/
frameworks/base/wifi/java/android/net/wifi/

5. WiFi Setup Section

Located in packages/apps/settings/src/com/android/settings/wifi/

Two. Linux kernel configuration

With the original Android kernel support, add the WiFi kernel configuration as follows:

1. Networkingsupport--->wireless to increase the support of the 802.11 protocol stack

2. USB Support WiFi configuration

USB WiFi-enabled configuration options are located under the device DRIVERS>USB Support configuration menu USB Wireless

Device Management Support.

3. Mdev and firmware support configuration for user space

Enter the Devicedriver > Generic Driver Options Configuration menu and configure user space as shown in the following figure

Mdev and firmware support.

4. WIFI Device Support Configuration

Devicedrivers---> Network devicesupport---> Wireless LAN---> Ralink driver Support--->ralinkrt2800 (USB) Support (experimental)--->rt2800usb-include support forrt30xx (USB) devices

And the IEEE 802.11 for Host AP (PRISM2/2.5/3 andwep/tkip/ccmp) in the WIRELESS LAN directory is selected to open Config_wireless_ext=y Config_wext_ Priv=y

three. Driver Configuration and compilation

1. Modify the configuration file in the Driver SDK package

1.1 Modify ENV.MK, set Rt28xx_dir to the current directory, Rt28xx_dir = $ (shell pwd).

1.2 Modifying the corresponding kernel and cross compiler paths in makefile

1.3 Modifying GCC and LD variables in the config.mk of the Os/linux directory

1.4 Open Os/linux directory in Config.mk has_wpa_supplicant and Has_native_wpa_supplicant_support macros

2. Modify driver source in the Driver SDK package

2.1 Modify the Rtusb_urb_alloc_buffer and Rtusb_urb_free_buffer macros in rt_linux.h to define the following

#define Rtusb_urb_alloc_buffer (Pusb_dev,bufsize, pdma_addr) usb_alloc_coherent (pusb_dev,bufsize, GFP_ATOMIC, PDma_ Addr

#defineRTUSB_URB_FREE_BUFFER (Pusb_dev, BufSize, Ptransferbuf, dma_addr) usb_free_coherent (Pusb_dev, BUFSIZE,PTRANSF Erbuf, DMA_ADDR)

2.2 Modify RT_MAIN_DEV.C, directly mainvirtualif_close function empty, return 0, solve the problem can not be repeatedly turned off wifi.

2.3 Modify the Rtmposnetdevattach function in rt_linux.c to add devname assignment. strcpy (Pnetdev->name, "mlan0"); Note: (the name used here should be consistent with the node name used by the upper level, here is a description of the top of the main points in the use of the node name:

1,\frameworks\base\wifi\java\android\net\wifiwifistatetracker.java

2,init.rc start the Wpa_supplicant daemon inside and start the DHCPCD service

3,DHCPCD service configuration file, dhcpcd.conf inside

4,init.rc set SetProp wifi.interface "Mlan0")

3. Compiling method

Source Env.mk;make can be, drive is in the path of Os/linux under the Rt3070sta.ko. The driver name used here should be consistent with the driver name specified by the HAL layer WIFI.C

Four. Wap_supplicant Related configuration

Modification of 3.1 wpa_supplicant.conf configuration file

Used in Ctrl_interface=dir=/data/system/wpa_supplicantgroup=wifi #这个路径在wifi. C

3.2 The entire environment must be compiled for Wext type-related code.  That is, to open WEXT related macro config_driver_wext. That is, add in device/hisi/hi3716c/boardconfig.mk:
Board_have_wifi: = True
Board_wpa_supplicant_driver: = Wext

The purpose of this configuration is to make External/wpa_supplicant/android.mk set Wpa_build_supplicant to True.

3.3 Adding Wpa_supplicant daemon and dhcpcd process inside init.rc

3.4 in init.rc to add WiFi related file permission settings, set as follows:

chmod 0771/system/etc/wifi

chmod 0660/system/etc/wifi/wpa_supplicant.conf

Chown wifiwifi/system/etc/wifi/wpa_supplicant.conf #wifi的原始配置文件

#wpa_supplicantsocket

Mkdir/data/system/wpa_supplicant 0770 WiFi WiFi

chmod 0771/data/system/wpa_supplicant #放置wifiinterface的地方

Mkdir/data/misc/wifi 0770 WiFi WiFi

chmod 0771/data/misc/wifi

chmod 0660/data/misc/wifi/wpa_supplicant.conf #wifi的配置文件, the file will be written by wpa_supplicant according to the actual configuration

Chown Wifiwifi/data/misc/wifi

Chown wifiwifi/data/misc/wifi/wpa_supplicant.conf

Mkdir/data/misc/wifi/sockets 0770 WiFi WiFi #与上层通过socket通信的路径

cp/system/etc/wifi/wpa_supplicant.conf/data/misc/wifi/

MKDIR/DATA/MISC/DHCP 0777 DHCP DHCP

Chown DHCPDHCP/DATA/MISC/DHCP

# preparefor WiFi

Setpropwifi.interface "Mlan0"

SetProp Wlan.driver.status "OK"

3.5 Start wpa_supplicant daemon and DHCPCD service

Add wpa_supplicant start in init.rc:

Service wpa_supplicant/system/bin/logwrapper/system/bin/wpa_supplicant \

-dwext-imlan0-c/data/misc/wifi/wpa_supplicant.conf-dd

User root

Group System WiFi inet

Socket wpa_mlan0 Dgram 660 WiFi wifi