我想让 USB <> HDMI 设备工作，但我需要一些帮助来转换 DisplayLink 规则以与通用供应商（相同芯片组）一起使用。
Displaylink 规则如下所示：
# Copyright (c) 2016 - 2020 DisplayLink (UK) Ltd.
# File autogenerated by udev-installer.sh script
ACTION=="add",
SUBSYSTEM=="usb",
DRIVERS=="usb",
ATTR{idVendor}=="17e9",
IMPORT{builtin}="usb_id",
ENV{DISPLAYLINK_DEVNAME}="$env{DEVNAME}",
ENV{DISPLAYLINK_DEVICE_ID}="$env{ID_BUS}-$env{BUSNUM}-$env{DEVNUM}-$env{ID_SERIAL}",
ENV{REMOVE_CMD}="/opt/displaylink/udev.sh $root $env{DISPLAYLINK_DEVICE_ID} $env{DISPLAYLINK_DEVNAME}"
ACTION=="add",
SUBSYSTEM=="usb",
DRIVERS=="usb",
ATTRS{idVendor}=="17e9",
ATTR{bInterfaceClass}=="ff",
ATTR{bInterfaceProtocol}=="03",
IMPORT{parent}="DISPLAYLINK*",
RUN+="/opt/displaylink/udev.sh $root $env{DISPLAYLINK_DEVICE_ID} $env{DISPLAYLINK_DEVNAME}"
ACTION=="remove",
ENV{PRODUCT}=="17e9/*",
RUN+="/opt/displaylink/udev.sh $root $env{DEVNAME}"````
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When I run dmesg I get this:
[ 2141.202752] usb 1-2: new high-speed USB device number 8 using xhci_hcd
[ 2141.354003] usb 1-2: New USB device found, idVendor=534d, idProduct=6021, bcdDevice= 1.00
[ 2141.354008] usb 1-2: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[ 2141.354011] usb 1-2: Product: usb extscreen
[ 2141.354014] usb 1-2: Manufacturer: MACROSILICON
[ 2141.354016] usb 1-2: SerialNumber: 2018BA7160A0
[ 2141.357332] hid-generic 0003:534D:6021.0006: hiddev0,hidraw1: USB HID v1.10 Device [MACROSILICON usb extscreen] on usb-0000:00:14.0-2/input0
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and lsusb gives
Bus 001 Device 008: ID 534d:6021 MACROSILICON usb extscreen
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OK so I need to rewrite the DisplayLink rule to work with this vendor.
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Q1: I am assuming that the $root is just ./
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Q2: I know I have to change the vendor ID but where do the following vars come from
ENV{DISPLAYLINK_DEVNAME}="$env{DEVNAME}"
ENV{DISPLAYLINK_DEVICE_ID}="$env{ID_BUS}-$env{BUSNUM}-$env{DEVNUM}-$env{ID_SERIAL}"
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Q3: can I hard code the vars from Q2 into the rules file and if so what are they:
based on dmesg and lsusb above i am guessing:
DEVNAME = "usb extscreen"
ID_BUS = "1"
BUSNUM = "2"
ID_SERIAL = 2018BA7160A0
DEVNUM = changes each time ???
Any assistance would be appreciated ....
thanks