我有一台 Brother 7055 打印机/扫描仪和一台 Raspberry Pi，我想把它们都变成打印和扫描服务器。不幸的是，Brother 没有提供任何 ARM 驱动程序。我遇到了这关于 Raspberry Pi 上的 QEMU 仿真的博客文章，实际上我已经成功使用这种方法安装了 x86 打印机驱动程序，我通过 CUPS 分享它，一切都很好。现在我正在尝试使扫描仪正常工作，并且 Brother 软件已安装且没有任何错误，但当我运行时扫描仪不显示scanimage -L
扫描仪已连接：
dporobic@raspberrypi:~ $ lsusb
Bus 001 Device 005: ID 04f9:0248 Brother Industries, Ltd DCP-7055 scanner/printer
Bus 001 Device 003: ID 0424:ec00 Standard Microsystems Corp. SMSC9512/9514 Fast Ethernet Adapter
Bus 001 Device 002: ID 0424:9514 Standard Microsystems Corp.
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
但看不到扫描仪：
dporobic@raspberrypi:~ $ scanimage -L
No scanners were identified. If you were expecting something different,
check that the scanner is plugged in, turned on and detected by the
sane-find-scanner tool (if appropriate). Please read the documentation
which came with this software (README, FAQ, manpages).
sane-find-scanner 确实看到了一些东西，但无法使其工作，因为兄弟使用它自己的理智驱动程序。
porobic@raspberrypi:~ $ sudo sane-find-scanner
# sane-find-scanner will now attempt to detect your scanner. If the
# result is different from what you expected, first make sure your
# scanner is powered up and properly connected to your computer.
# No SCSI scanners found. If you expected something different, make sure that
# you have loaded a kernel SCSI driver for your SCSI adapter.
# Also you need support for SCSI Generic (sg) in your operating system.
# If using Linux, try "modprobe sg".
found USB scanner (vendor=0x04f9, product=0x0248) at libusb:001:005
found USB scanner (vendor=0x0424, product=0xec00) at libusb:001:003
# Your USB scanner was (probably) detected. It may or may not be supported by
# SANE. Try scanimage -L and read the backend's manpage.
# Not checking for parallel port scanners.
# Most Scanners connected to the parallel port or other proprietary ports
# can't be detected by this program.
调试 scanimage 给出以下输出，看起来 Brother4 lib 无法加载：
dporobic@raspberrypi:~ $ sudo SANE_DEBUG_DLL=255 scanimage -L
[sanei_debug] Setting debug level of dll to 255.
[dll] sane_init: SANE dll backend version 1.0.13 from sane-backends 1.0.24
[dll] sane_init/read_dlld: attempting to open directory `./dll.d'
[dll] sane_init/read_dlld: attempting to open directory `/etc/sane.d/dll.d'
[dll] sane_init/read_dlld: using config directory `/etc/sane.d/dll.d'
[dll] sane_init/read_dlld: considering /etc/sane.d/dll.d/libsane-extras
[dll] sane_init/read_config: reading dll.d/libsane-extras
[dll] sane_init/read_dlld: done.
[dll] sane_init/read_config: reading dll.conf
[dll] add_backend: adding backend `brother4'
[dll] sane_get_devices
[dll] load: searching backend `brother4' in `/usr/lib/arm-linux-gnueabihf/sane:/usr/lib/sane'
[dll] load: trying to load `/usr/lib/arm-linux-gnueabihf/sane/libsane-brother4.so.1'
[dll] load: dlopen()ing `/usr/lib/arm-linux-gnueabihf/sane/libsane-brother4.so.1'
**[dll] load: dlopen() failed (/usr/lib/arm-linux-gnueabihf/sane/libsane-brother4.so.1: cannot open shared object file: No such file or directory)**
[dll] sane_get_devices: found 0 devices
No scanners were identified. If you were expecting something different,
check that the scanner is plugged in, turned on and detected by the
sane-find-scanner tool (if appropriate). Please read the documentation
which came with this software (README, FAQ, manpages).
[dll] sane_exit: exiting
[dll] sane_exit: finished
lib 文件在那里，但看起来无法打开或访问这些文件：
dporobic@raspberrypi:~ $ ls -l /usr/lib/arm-linux-gnueabihf/sane/ | grep brother
-rwxr-xr-x 1 root root 129696 Jan 8 11:08 libsane-brother4.so
-rwxr-xr-x 1 root root 129696 Jan 8 11:08 libsane-brother4.so.1
-rwxr-xr-x 1 root root 129696 Jan 8 11:08 libsane-brother4.so.1.0.7
也许 libsane-brother4.so 库的某些依赖项丢失，但运行 objdump -x 并在动态部分下查看会得到以下输出（我对 objdump 不太熟悉，所以我希望我能正确解释这一点）：
dporobic@raspberrypi:~ $ objdump -x /usr/lib/arm-linux-gnueabihf/sane/libsane-brother4.so | grep NEEDED
NEEDED libpthread.so.0
NEEDED libnsl.so.1
NEEDED libusb-0.1.so.4
NEEDED libm.so.6
NEEDED libdl.so.2
NEEDED libc.so.6
我的 Pi 上似乎有这些库，其中只有一个仅作为 ARM 版本提供，而不作为 i386 版本提供，所有其他库都包含在这两个版本中：
dporobic@raspberrypi:~ $ sudo ldconfig -p | grep -E 'libpthread.so.0|libnsl.so.1|libusb-0.1.so.4|libm.so.6|libdl.so.2|libc.so.6'
libusb-0.1.so.4 (libc6,hard-float) => /lib/arm-linux-gnueabihf/libusb-0.1.so.4
libusb-0.1.so.4 (libc6,hard-float) => /usr/lib/arm-linux-gnueabihf/libusb-0.1.so.4
libpthread.so.0 (libc6,hard-float, OS ABI: Linux 2.6.32) => /lib/arm-linux-gnueabihf/libpthread.so.0
libpthread.so.0 (libc6, OS ABI: Linux 2.6.32) => /lib/i386-linux-gnu/libpthread.so.0
libnsl.so.1 (libc6,hard-float, OS ABI: Linux 2.6.32) => /lib/arm-linux-gnueabihf/libnsl.so.1
libnsl.so.1 (libc6, OS ABI: Linux 2.6.32) => /lib/i386-linux-gnu/libnsl.so.1
libm.so.6 (libc6,hard-float, OS ABI: Linux 2.6.32) => /lib/arm-linux-gnueabihf/libm.so.6
libm.so.6 (libc6, OS ABI: Linux 2.6.32) => /lib/i386-linux-gnu/libm.so.6
libdl.so.2 (libc6,hard-float, OS ABI: Linux 2.6.32) => /lib/arm-linux-gnueabihf/libdl.so.2
libdl.so.2 (libc6, OS ABI: Linux 2.6.32) => /lib/i386-linux-gnu/libdl.so.2
libc.so.6 (libc6,hard-float, OS ABI: Linux 2.6.32) => /lib/arm-linux-gnueabihf/libc.so.6
libc.so.6 (ELF, OS ABI: Linux 2.6.32) => /lib/i386-linux-gnu/libc.so.6
但我需要的一个库没有列出，可能这就是它无法加载的原因：
dporobic@raspberrypi:~ $ sudo ldconfig -p | grep libsane-brother4.so
dporobic@raspberrypi:~ $
最初 borther4 lib 位于/usr/lib/sane，我已添加此路径/etc/ld.so.conf.d/libsane-brother.conf并运行，但只有在签入时才sudo ldconfig获得此库：libsane.so.1ldconfig -v
dporobic@raspberrypi:~ $ sudo ldconfig -v 2>/dev/null | grep brother -B1
/usr/lib/sane:
libsane.so.1 -> libsane-brother4.so.1.0.7
无法使libsane-brother.so.1lib 出现在 ld 缓存中...
更新
它似乎与 dlconfig 无关，在我的 opensuse 机器上，扫描仪正在工作，它libsane-brother.so.1 lib没有显示在 ldconfig 缓存中，就像在 Pi 上一样，但加载 lib 没有任何问题。
dporobic@latitude:~> sudo ldconfig -v 2>/dev/null | grep -E 'sane|brother'
libksane.so.0 -> libksane.so.0.2.0
libsane.so.1 -> libsane.so.1.0.24
加载正确，没有错误：
dporobic@latitude:~> sudo SANE_DEBUG_DLL=255 scanimage -L
[sanei_debug] Setting debug level of dll to 255.
[dll] sane_init: SANE dll backend version 1.0.13 from sane-backends 1.0.24
[dll] sane_init/read_dlld: attempting to open directory `./dll.d'
[dll] sane_init/read_dlld: attempting to open directory `/etc/sane.d/dll.d'
[dll] sane_init/read_dlld: opendir failed: No such file or directory
[dll] sane_init/read_config: reading dll.conf
[dll] add_backend: adding backend `brother4'
[dll] sane_get_devices
[dll] load: searching backend `brother4' in `/usr/lib64/sane'
[dll] load: trying to load `/usr/lib64/sane/libsane-brother4.so.1'
**[dll] load: dlopen()ing `/usr/lib64/sane/libsane-brother4.so.1'**
[dll] init: initializing backend `brother4'
[dll] init: backend `brother4' is version 1.0.1
[dll] sane_get_devices: found 1 devices
device `brother4:bus2;dev1' is a Brother DCP-7055 USB scanner
[dll] sane_exit: exiting
[dll] sane_exit: calling backend `brother4's exit function
[dll] sane_exit: finished
libsane-brother.so.1 lib那么现在的问题是为什么Sane即使在正确的路径上也无法打开......
注意：当我运行时，会出现直接连接到我的 OpenSuse 机器并安装了相同驱动程序的相同扫描仪，scanimage -L因此它必须能够正常工作，这里唯一值得怀疑的是 Pi。
答案1
去年我解决了类似的挑战。在arm上（与Armbian，Raspian是一样的），我首先在这台机器上的qemu打印的帮助下安装（mfc 795cw）。扫描仪无法工作，但需要在该arm linux上安装扫描失败的驱动程序。为了进行扫描，我设置了一个 chroot 环境。您需要一个与 Brother Linux 驱动程序相关的当年使用的 Linux 版本。因此我使用Lubuntu 10.04。请注意不要卸载 lpr!。你必须在这个 chroot 环境中运行 Brother linux 安装程序。然后在arm-Linux 中打印，在chroot i368 Linux 中扫描。我设置了一个用于扫描的脚本，以使用 scanimage 启动 chroot（安装 -o bind、qemu，....）。
答案2
这是因为使用的是 sane (armhf) 而不是 i383 架构。如果您安装架构 i386 的 sane，您将加载驱动程序 libsane-brother4.so.1。但此时我遇到了一个问题，sane（i386）无法与libusb（armhf）一起使用。这是内核模块而不是用户级别。我不明白如何解决这个问题。
答案3
这将需要 qemu 系统模拟，因此可能运行例如 DSL 来宾与 cups 和 saned 共享 USB 打印机/扫描仪与主机 raspbian 重新与世界其他地方（或您的本地网络）共享。这只是一个想法，不知道是否实用。