从此处的 Brother 站点下载并安装了 linux 驱动程序。
但扫描仪仍然无法识别。
可以看到，驱动安装成功：
$ dpkg -l | grep Brother
ii brother-cups-wrapper-common 1.0.0-10-0ubuntu6 amd64 Common files for Brother cups wrapper packages
ii brother-udev-rule-type1 1.0.0-1 all Brother udev rule type 1
ii brscan-skey 0.2.4-1 amd64 Brother Linux scanner S-KEY tool
ii brscan2 0.2.5-1 amd64 Brother Scanner Driver
ii printer-driver-brlaser 3-5~ubuntu1 amd64 printer driver for (some) Brother laser printers
ii printer-driver-ptouch 1.4-1 amd64 printer driver Brother P-touch label printers
在这里，您可以看到已安装的驱动程序认为它未“注册”：
$ brscan-skey -l
DCP-350C : brother2:bus3;dev1 : …