我有一个带有USB设备接口的嵌入式Linux 3.19系统。该设备需要向主机公开三个USB接口:一个虚拟网络接口(RNDIS或CDC ECM)和两个虚拟串行端口(CDC ACM)。该设备需要与现代Windows(7+)和Linux(3.16+)主机配合使用。
由于Windows本身不支持CDC ECM,我们决定实现两种USB配置(这是一种流行的方法:]]
目的是让Windows通过RNDIS使用第一个配置,这是本机支持的(Windows始终选择第一个USB配置);并让非Windows主机通过CDC ECM使用第二种配置。
我整理了一个脚本(基于David Lechner的类似脚本):http://pastebin.com/VtAusEmf。下面提供了脚本的相关部分(请点击链接查看完整的脚本,它相当大):
mkdir -p ${g} echo "${usb_ver}" > ${g}/bcdUSB echo "${dev_class}" > ${g}/bDeviceClass echo "${vid}" > ${g}/idVendor echo "${pid}" > ${g}/idProduct mkdir ${g}/strings/0x409 echo "${mfg}" > ${g}/strings/0x409/manufacturer echo "${prod}" > ${g}/strings/0x409/product echo "${serial}" > ${g}/strings/0x409/serialnumber mkdir ${g}/configs/c.1 echo "${attr}" > ${g}/configs/c.1/bmAttributes echo "${pwr}" > ${g}/configs/c.1/MaxPower mkdir ${g}/configs/c.1/strings/0x409 echo "${cfg1}" > ${g}/configs/c.1/strings/0x409/configuration echo "1" > ${g}/os_desc/use echo "${ms_vendor_code}" > ${g}/os_desc/b_vendor_code echo "${ms_qw_sign}" > ${g}/os_desc/qw_sign mkdir ${g}/functions/rndis.usb0 echo "${dev_mac}" > ${g}/functions/rndis.usb0/dev_addr echo "${host_mac}" > ${g}/functions/rndis.usb0/host_addr echo "${ms_compat_id}" > ${g}/functions/rndis.usb0/os_desc/interface.rndis/compatible_id echo "${ms_subcompat_id}" > ${g}/functions/rndis.usb0/os_desc/interface.rndis/sub_compatible_id mkdir ${g}/configs/c.2 echo "${attr}" > ${g}/configs/c.2/bmAttributes echo "${pwr}" > ${g}/configs/c.2/MaxPower mkdir ${g}/configs/c.2/strings/0x409 echo "${cfg2}" > ${g}/configs/c.2/strings/0x409/configuration mkdir ${g}/functions/ecm.usb0 echo "${dev_mac}" > ${g}/functions/ecm.usb0/dev_addr echo "${host_mac}" > ${g}/functions/ecm.usb0/host_addr mkdir ${g}/functions/acm.GS0 mkdir ${g}/functions/acm.GS1 ln -s ${g}/configs/c.1 ${g}/os_desc ln -s ${g}/functions/rndis.usb0 ${g}/configs/c.1 ln -s ${g}/functions/acm.GS0 ${g}/configs/c.1 ln -s ${g}/functions/acm.GS1 ${g}/configs/c.1 ln -s ${g}/functions/ecm.usb0 ${g}/configs/c.2 ln -s ${g}/functions/acm.GS0 ${g}/configs/c.2 ln -s ${g}/functions/acm.GS1 ${g}/configs/c.2 echo "${device}" > ${g}/UDC
所得的Gadget配置在Linux主机上正常工作(选择了第二个配置,所有三个接口均可用并且正常工作),但是Windows主机(经过8和10测试)仅检测RNDIS接口,而忽略了ACM接口。 RNDIS效果很好。
如果禁用RNDIS接口,则Windows主机将仅检测第一个ACM接口,而忽略第二个。
我怀疑Windows无法正确处理复合USB设备。是这样,还是我做错了什么?如果是这样,我是否必须编写我自己的.inf
文件,并指定需要加载哪些类驱动程序?
我有一个带有USB设备接口的嵌入式Linux 3.19系统。设备需要向主机公开三个USB接口:一个虚拟网络接口(RNDIS或CDC ECM)和两个虚拟串行接口。]]