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区分两个相似的 USB 设备

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区分两个相似的 USB 设备

这个问题之前已经问过很多次了，但我还没有找到适合我的情况的可行解决方案。就我而言，我有两个基于 FTDI 的 USB <-> 串行转换器，我无法在其中找到任何可区分的特征，以将其包含在我打算编写的 udev 规则中，以便用永久名称来识别它们。输出：

udevadm info --attribute-walk --path=/sys/bus/usb-serial/devices/ttyUSB0

looking at parent device '/devices/pci0000:00/0000:00:14.0/usb3/3-1/3-1:1.0':
    KERNELS=="3-1:1.0"
    SUBSYSTEMS=="usb"
    DRIVERS=="ftdi_sio"
    ATTRS{bInterfaceClass}=="ff"
    ATTRS{bInterfaceSubClass}=="ff"
    ATTRS{bInterfaceProtocol}=="ff"
    ATTRS{bNumEndpoints}=="02"
    ATTRS{supports_autosuspend}=="1"
    ATTRS{bAlternateSetting}==" 0"
    ATTRS{bInterfaceNumber}=="00"
    ATTRS{interface}=="USB <-> Serial"

  looking at parent device '/devices/pci0000:00/0000:00:14.0/usb3/3-1':
    KERNELS=="3-1"
    SUBSYSTEMS=="usb"
    DRIVERS=="usb"
    ATTRS{bDeviceSubClass}=="00"
    ATTRS{bDeviceProtocol}=="00"
    ATTRS{devpath}=="1"
    ATTRS{idVendor}=="0403"
    ATTRS{speed}=="12"
    ATTRS{bNumInterfaces}==" 1"
    ATTRS{bConfigurationValue}=="1"
    ATTRS{bMaxPacketSize0}=="8"
    ATTRS{busnum}=="3"
    ATTRS{devnum}=="21"
    ATTRS{configuration}==""
    ATTRS{bMaxPower}=="90mA"
    ATTRS{authorized}=="1"
    ATTRS{bmAttributes}=="80"
    ATTRS{bNumConfigurations}=="1"
    ATTRS{maxchild}=="0"
    ATTRS{bcdDevice}=="0400"
    ATTRS{avoid_reset_quirk}=="0"
    ATTRS{quirks}=="0x0"
    ATTRS{version}==" 1.10"
    ATTRS{urbnum}=="11"
    ATTRS{ltm_capable}=="no"
    ATTRS{manufacturer}=="FTDI"
    ATTRS{removable}=="removable"
    ATTRS{idProduct}=="6001"
    ATTRS{bDeviceClass}=="00"
    ATTRS{product}=="USB <-> Serial"

  looking at parent device '/devices/pci0000:00/0000:00:14.0/usb3':
    KERNELS=="usb3"
    SUBSYSTEMS=="usb"
    DRIVERS=="usb"
    ATTRS{bDeviceSubClass}=="00"
    ATTRS{bDeviceProtocol}=="01"
    ATTRS{devpath}=="0"
    ATTRS{idVendor}=="1d6b"
    ATTRS{speed}=="480"
    ATTRS{bNumInterfaces}==" 1"
    ATTRS{bConfigurationValue}=="1"
    ATTRS{bMaxPacketSize0}=="64"
    ATTRS{authorized_default}=="1"
    ATTRS{busnum}=="3"
    ATTRS{devnum}=="1"
    ATTRS{configuration}==""
    ATTRS{bMaxPower}=="0mA"
    ATTRS{authorized}=="1"
    ATTRS{bmAttributes}=="e0"
    ATTRS{bNumConfigurations}=="1"
    ATTRS{maxchild}=="4"
    ATTRS{bcdDevice}=="0313"
    ATTRS{avoid_reset_quirk}=="0"
    ATTRS{quirks}=="0x0"
    ATTRS{serial}=="0000:00:14.0"
    ATTRS{version}==" 2.00"
    ATTRS{urbnum}=="383"
    ATTRS{ltm_capable}=="no"
    ATTRS{manufacturer}=="Linux 3.13.0-32-generic xhci_hcd"
    ATTRS{removable}=="unknown"
    ATTRS{idProduct}=="0002"
    ATTRS{bDeviceClass}=="09"
    ATTRS{product}=="xHCI Host Controller"

  looking at parent device '/devices/pci0000:00/0000:00:14.0':
    KERNELS=="0000:00:14.0"
    SUBSYSTEMS=="pci"
    DRIVERS=="xhci_hcd"
    ATTRS{irq}=="40"
    ATTRS{subsystem_vendor}=="0x17aa"
    ATTRS{broken_parity_status}=="0"
    ATTRS{class}=="0x0c0330"
    ATTRS{enabled}=="1"
    ATTRS{consistent_dma_mask_bits}=="64"
    ATTRS{dma_mask_bits}=="64"
    ATTRS{local_cpus}=="ff"
    ATTRS{device}=="0x1e31"
    ATTRS{msi_bus}==""
    ATTRS{local_cpulist}=="0-7"
    ATTRS{vendor}=="0x8086"
    ATTRS{subsystem_device}=="0x3977"
    ATTRS{d3cold_allowed}=="1"

  looking at parent device '/devices/pci0000:00':
    KERNELS=="pci0000:00"
    SUBSYSTEMS==""
    DRIVERS==""

对 ttyUSB1 执行的操作也是一样的：

udevadm info --attribute-walk --path=/sys/bus/usb-serial/devices/ttyUSB1

looking at device '/devices/pci0000:00/0000:00:14.0/usb3/3-2/3-2:1.0/ttyUSB1':
    KERNEL=="ttyUSB1"
    SUBSYSTEM=="usb-serial"
    DRIVER=="ftdi_sio"
    ATTR{port_number}=="0"
    ATTR{latency_timer}=="1"

  looking at parent device '/devices/pci0000:00/0000:00:14.0/usb3/3-2/3-2:1.0':
    KERNELS=="3-2:1.0"
    SUBSYSTEMS=="usb"
    DRIVERS=="ftdi_sio"
    ATTRS{bInterfaceClass}=="ff"
    ATTRS{bInterfaceSubClass}=="ff"
    ATTRS{bInterfaceProtocol}=="ff"
    ATTRS{bNumEndpoints}=="02"
    ATTRS{supports_autosuspend}=="1"
    ATTRS{bAlternateSetting}==" 0"
    ATTRS{bInterfaceNumber}=="00"
    ATTRS{interface}=="USB <-> Serial"

  looking at parent device '/devices/pci0000:00/0000:00:14.0/usb3/3-2':
    KERNELS=="3-2"
    SUBSYSTEMS=="usb"
    DRIVERS=="usb"
    ATTRS{bDeviceSubClass}=="00"
    ATTRS{bDeviceProtocol}=="00"
    ATTRS{devpath}=="2"
    ATTRS{idVendor}=="0403"
    ATTRS{speed}=="12"
    ATTRS{bNumInterfaces}==" 1"
    ATTRS{bConfigurationValue}=="1"
    ATTRS{bMaxPacketSize0}=="8"
    ATTRS{busnum}=="3"
    ATTRS{devnum}=="22"
    ATTRS{configuration}==""
    ATTRS{bMaxPower}=="90mA"
    ATTRS{authorized}=="1"
    ATTRS{bmAttributes}=="80"
    ATTRS{bNumConfigurations}=="1"
    ATTRS{maxchild}=="0"
    ATTRS{bcdDevice}=="0400"
    ATTRS{avoid_reset_quirk}=="0"
    ATTRS{quirks}=="0x0"
    ATTRS{version}==" 1.10"
    ATTRS{urbnum}=="11"
    ATTRS{ltm_capable}=="no"
    ATTRS{manufacturer}=="FTDI"
    ATTRS{removable}=="removable"
    ATTRS{idProduct}=="6001"
    ATTRS{bDeviceClass}=="00"
    ATTRS{product}=="USB <-> Serial"

  looking at parent device '/devices/pci0000:00/0000:00:14.0/usb3':
    KERNELS=="usb3"
    SUBSYSTEMS=="usb"
    DRIVERS=="usb"
    ATTRS{bDeviceSubClass}=="00"
    ATTRS{bDeviceProtocol}=="01"
    ATTRS{devpath}=="0"
    ATTRS{idVendor}=="1d6b"
    ATTRS{speed}=="480"
    ATTRS{bNumInterfaces}==" 1"
    ATTRS{bConfigurationValue}=="1"
    ATTRS{bMaxPacketSize0}=="64"
    ATTRS{authorized_default}=="1"
    ATTRS{busnum}=="3"
    ATTRS{devnum}=="1"
    ATTRS{configuration}==""
    ATTRS{bMaxPower}=="0mA"
    ATTRS{authorized}=="1"
    ATTRS{bmAttributes}=="e0"
    ATTRS{bNumConfigurations}=="1"
    ATTRS{maxchild}=="4"
    ATTRS{bcdDevice}=="0313"
    ATTRS{avoid_reset_quirk}=="0"
    ATTRS{quirks}=="0x0"
    ATTRS{serial}=="0000:00:14.0"
    ATTRS{version}==" 2.00"
    ATTRS{urbnum}=="383"
    ATTRS{ltm_capable}=="no"
    ATTRS{manufacturer}=="Linux 3.13.0-32-generic xhci_hcd"
    ATTRS{removable}=="unknown"
    ATTRS{idProduct}=="0002"
    ATTRS{bDeviceClass}=="09"
    ATTRS{product}=="xHCI Host Controller"

  looking at parent device '/devices/pci0000:00/0000:00:14.0':
    KERNELS=="0000:00:14.0"
    SUBSYSTEMS=="pci"
    DRIVERS=="xhci_hcd"
    ATTRS{irq}=="40"
    ATTRS{subsystem_vendor}=="0x17aa"
    ATTRS{broken_parity_status}=="0"
    ATTRS{class}=="0x0c0330"
    ATTRS{enabled}=="1"
    ATTRS{consistent_dma_mask_bits}=="64"
    ATTRS{dma_mask_bits}=="64"
    ATTRS{local_cpus}=="ff"
    ATTRS{device}=="0x1e31"
    ATTRS{msi_bus}==""
    ATTRS{local_cpulist}=="0-7"
    ATTRS{vendor}=="0x8086"
    ATTRS{subsystem_device}=="0x3977"
    ATTRS{d3cold_allowed}=="1"

  looking at parent device '/devices/pci0000:00':
    KERNELS=="pci0000:00"
    SUBSYSTEMS==""
    DRIVERS==""

我尝试实施第一个解决方案@如何区分相同的 USB 转串口适配器？通过分配KERNELS=="3-1"给 ttyUSB0 和KERNELS=="3-2"ttyUSB1，但它不是持久的，每次我重新连接设备时都会发生变化。此外，ATTRS{devnum}每次也会不断变化，但可以注意到它们始终是连续的。那么，我可以使用它们来修复设备名称吗？我不确定同一设备是否总是用较小或较大的 devnum 进行初始化。

我尝试了以下另一个选项如何将设备 ID 锁定到端口地址？，并做了：

udevadm info /dev/ttyUSB0

P: /devices/pci0000:00/0000:00:14.0/usb3/3-1/3-1:1.0/ttyUSB0/tty/ttyUSB0
N: ttyUSB0
S: serial/by-id/usb-FTDI_USB__-__Serial-if00-port0
S: serial/by-path/pci-0000:00:14.0-usb-0:1:1.0-port0
E: DEVLINKS=/dev/serial/by-id/usb-FTDI_USB__-__Serial-if00-port0 /dev/serial/by-path/pci-0000:00:14.0-usb-0:1:1.0-port0
E: DEVNAME=/dev/ttyUSB0
E: DEVPATH=/devices/pci0000:00/0000:00:14.0/usb3/3-1/3-1:1.0/ttyUSB0/tty/ttyUSB0
E: ID_BUS=usb
E: ID_MM_CANDIDATE=1
E: ID_MODEL=USB__-__Serial
E: ID_MODEL_ENC=USB\x20\x3c-\x3e\x20Serial
E: ID_MODEL_FROM_DATABASE=FT232 USB-Serial (UART) IC
E: ID_MODEL_ID=6001
E: ID_PATH=pci-0000:00:14.0-usb-0:1:1.0
E: ID_PATH_TAG=pci-0000_00_14_0-usb-0_1_1_0
E: ID_REVISION=0400
E: ID_SERIAL=FTDI_USB__-__Serial
E: ID_TYPE=generic
E: ID_USB_DRIVER=ftdi_sio
E: ID_USB_INTERFACES=:ffffff:
E: ID_USB_INTERFACE_NUM=00
E: ID_VENDOR=FTDI
E: ID_VENDOR_ENC=FTDI
E: ID_VENDOR_FROM_DATABASE=Future Technology Devices International, Ltd
E: ID_VENDOR_ID=0403
E: MAJOR=188
E: MINOR=0
E: SUBSYSTEM=tty
E: USEC_INITIALIZED=8719192

进而：

udevadm info /dev/ttyUSB1

P: /devices/pci0000:00/0000:00:14.0/usb3/3-2/3-2:1.0/ttyUSB1/tty/ttyUSB1
N: ttyUSB1
S: serial/by-id/usb-FTDI_USB__-__Serial-if00-port0
S: serial/by-path/pci-0000:00:14.0-usb-0:2:1.0-port0
E: DEVLINKS=/dev/serial/by-id/usb-FTDI_USB__-__Serial-if00-port0 /dev/serial/by-path/pci-0000:00:14.0-usb-0:2:1.0-port0
E: DEVNAME=/dev/ttyUSB1
E: DEVPATH=/devices/pci0000:00/0000:00:14.0/usb3/3-2/3-2:1.0/ttyUSB1/tty/ttyUSB1
E: ID_BUS=usb
E: ID_MM_CANDIDATE=1
E: ID_MODEL=USB__-__Serial
E: ID_MODEL_ENC=USB\x20\x3c-\x3e\x20Serial
E: ID_MODEL_FROM_DATABASE=FT232 USB-Serial (UART) IC
E: ID_MODEL_ID=6001
E: ID_PATH=pci-0000:00:14.0-usb-0:2:1.0
E: ID_PATH_TAG=pci-0000_00_14_0-usb-0_2_1_0
E: ID_REVISION=0400
E: ID_SERIAL=FTDI_USB__-__Serial
E: ID_TYPE=generic
E: ID_USB_DRIVER=ftdi_sio
E: ID_USB_INTERFACES=:ffffff:
E: ID_USB_INTERFACE_NUM=00
E: ID_VENDOR=FTDI
E: ID_VENDOR_ENC=FTDI
E: ID_VENDOR_FROM_DATABASE=Future Technology Devices International, Ltd
E: ID_VENDOR_ID=0403
E: MAJOR=188
E: MINOR=1
E: SUBSYSTEM=tty
E: USEC_INITIALIZED=79099407

然后将 udev 规则写入位于 /etc/udev/rules.d/ 的文件中，作为 44-my-devices.rules： SUBSYSTEM=="tty", ENV{ID_PATH}=="pci-0000:00:14.0-usb-0:1:1.0", SYMLINK+="ttyUSBMotor1"

SUBSYSTEM=="tty", ENV{ID_PATH}=="pci-0000:00:14.0-usb-0:2:1.0", SYMLINK+="ttyUSBMotor2"

我还将其复制到 /lib/udev/rules.d/，然后重新加载规则：

sudo udevadm control --reload-rules

sudo /etc/init.d/udev restart

但什么也没发生。我想我在这里犯了一些错误，因为这应该有效。相关的硬件始终保持不变，规则一定有效。我也试过重启电脑，但没有效果。

答案1

好吧，使用端口的物理路径对我来说是可行的，因为我会一直保持设备连接，因此将设备连接到特定端口并使用它来识别两个相同设备中的一个是一种很好的方法。需要注意的一点是，我必须将 /etc/udev/rules.d 中的 udev 规则文件重命名为my-devices.rules文件44-my-devices.rules中指出的README：

If the ordering of files in this directory are not important to you,
it's recommended that you simply name your files "descriptive-name.rules"
such that they are processed AFTER all numbered rules in both this
directory and /lib/udev/rules.d and thus override anything set there.

这似乎对我有用，并且我能够用用户可理解的永久名称复制端口。

$ ls /dev/ttyUSB*
/dev/ttyUSB0  /dev/ttyUSB1  /dev/ttyUSBMotor1  /dev/ttyUSBMotor2

希望它能够帮助像我这样的人。

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