我有一个外部 USB 3.0 Lexar 多卡读卡器，我主要用它把 SD 卡上的照片从相机传输到 Shotwell。在 15.10 下，一切都运行良好：回到过去的美好时光，卡插入读卡器后会立即被检测到，Shotwell 启动，新的图像文件显示出来，所有这些都是默认的。
我已更新至 16.04 并且它停止工作了。
我努力了：
sudo sh -c "apt-add-repository restricted; apt-get update; apt-get install linux-generic linux-firmware linux-firmware-nonfree"
（linux-firmware-nonfree不存在，无效）
sudo sh -c 'echo 1 > /sys/bus/pci/rescan'
（这没有明显的效果）
类似问题中请求的各种故障排除输出：
lsusb：
Bus 002 Device 003: ID 8087:07da Intel Corp.
Bus 002 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 003: ID 1bcf:288f Sunplus Innovation Technology Inc.
Bus 001 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 004 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 003 Device 002: ID 0b95:772b ASIX Electronics Corp. AX88772B
Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
lspci-v：
00:14.0 USB controller: Intel Corporation 7 Series/C210 Series Chipset Family USB xHCI Host Controller (rev 04) (prog-if 30 [XHCI])
Subsystem: Dell 7 Series/C210 Series Chipset Family USB xHCI Host Controller
Flags: bus master, medium devsel, latency 0, IRQ 24
Memory at d0500000 (64-bit, non-prefetchable) [size=64K]
Capabilities: <access denied>
Kernel driver in use: xhci_hcd
00:1a.0 USB controller: Intel Corporation 7 Series/C210 Series Chipset Family USB Enhanced Host Controller #2 (rev 04) (prog-if 20 [EHCI])
Subsystem: Dell 7 Series/C210 Series Chipset Family USB Enhanced Host Controller
Flags: bus master, medium devsel, latency 0, IRQ 16
Memory at d051a000 (32-bit, non-prefetchable) [size=1K]
Capabilities: <access denied>
Kernel driver in use: ehci-pci
00:1d.0 USB controller: Intel Corporation 7 Series/C210 Series Chipset Family USB Enhanced Host Controller #1 (rev 04) (prog-if 20 [EHCI])
Subsystem: Dell 7 Series/C210 Series Chipset Family USB Enhanced Host Controller
Flags: bus master, medium devsel, latency 0, IRQ 23
Memory at d0519000 (32-bit, non-prefetchable) [size=1K]
Capabilities: <access denied>
Kernel driver in use: ehci-pci
dmesg：
[ 0.000000] Initializing cgroup subsys cpuset
[ 0.000000] Initializing cgroup subsys cpu
[ 0.000000] Initializing cgroup subsys cpuacct
[ 0.000000] Linux version 4.4.0-38-generic (buildd@lgw01-58) (gcc version 5.4.0 20160609 (Ubuntu 5.4.0-6ubuntu1~16.04.2) ) #57-Ubuntu SMP Tue Sep 6 15:42:33 UTC 2016 (Ubuntu 4.4.0-38.57-generic 4.4.19)
[ 0.000000] Command line: BOOT_IMAGE=/vmlinuz-4.4.0-38-generic root=/dev/mapper/ubuntu--vg-root ro quiet splash vt.handoff=7
消息 | grep usb：
[ 0.181730] usbcore: registered new interface driver usbfs
[ 0.181740] usbcore: registered new interface driver hub
[ 0.181759] usbcore: registered new device driver usb
[ 1.054245] usb usb1: New USB device found, idVendor=1d6b, idProduct=0002
[ 1.054247] usb usb1: New USB device strings: Mfr=3, Product=2, SerialNumber=1
[ 1.054249] usb usb1: Product: EHCI Host Controller
[ 1.054251] usb usb1: Manufacturer: Linux 4.4.0-38-generic ehci_hcd
[ 1.054253] usb usb1: SerialNumber: 0000:00:1a.0
[ 1.070363] usb usb2: New USB device found, idVendor=1d6b, idProduct=0002
[ 1.070368] usb usb2: New USB device strings: Mfr=3, Product=2, SerialNumber=1
[ 1.070371] usb usb2: Product: EHCI Host Controller
[ 1.070372] usb usb2: Manufacturer: Linux 4.4.0-38-generic ehci_hcd
[ 1.070374] usb usb2: SerialNumber: 0000:00:1d.0
[ 1.072355] usb usb3: New USB device found, idVendor=1d6b, idProduct=0002
[ 1.072358] usb usb3: New USB device strings: Mfr=3, Product=2, SerialNumber=1
[ 1.072360] usb usb3: Product: xHCI Host Controller
[ 1.072361] usb usb3: Manufacturer: Linux 4.4.0-38-generic xhci-hcd
[ 1.072363] usb usb3: SerialNumber: 0000:00:14.0
[ 1.073079] usb usb4: New USB device found, idVendor=1d6b, idProduct=0003
[ 1.073081] usb usb4: New USB device strings: Mfr=3, Product=2, SerialNumber=1
[ 1.073083] usb usb4: Product: xHCI Host Controller
[ 1.073085] usb usb4: Manufacturer: Linux 4.4.0-38-generic xhci-hcd
[ 1.073086] usb usb4: SerialNumber: 0000:00:14.0
[ 1.366229] usb 1-1: new high-speed USB device number 2 using ehci-pci
[ 1.382227] usb 2-1: new high-speed USB device number 2 using ehci-pci
[ 1.382248] usb 3-2: new high-speed USB device number 2 using xhci_hcd
[ 1.499066] usb 1-1: New USB device found, idVendor=8087, idProduct=0024
[ 1.499070] usb 1-1: New USB device strings: Mfr=0, Product=0, SerialNumber=0
[ 1.515069] usb 2-1: New USB device found, idVendor=8087, idProduct=0024
[ 1.515072] usb 2-1: New USB device strings: Mfr=0, Product=0, SerialNumber=0
[ 1.580568] usb 3-2: New USB device found, idVendor=0b95, idProduct=772b
[ 1.580572] usb 3-2: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[ 1.580573] usb 3-2: Product: AX88772B
[ 1.580575] usb 3-2: Manufacturer: ASIX Elec. Corp.
[ 1.580576] usb 3-2: SerialNumber: 0C15E4
[ 1.770282] usb 1-1.5: new high-speed USB device number 3 using ehci-pci
[ 1.786257] usb 2-1.5: new full-speed USB device number 3 using ehci-pci
[ 1.883283] usb 2-1.5: New USB device found, idVendor=8087, idProduct=07da
[ 1.883286] usb 2-1.5: New USB device strings: Mfr=0, Product=0, SerialNumber=0
[ 2.156116] usb 1-1.5: New USB device found, idVendor=1bcf, idProduct=288f
[ 2.156120] usb 1-1.5: New USB device strings: Mfr=1, Product=2, SerialNumber=0
[ 2.156122] usb 1-1.5: Product: Laptop_Integrated_Webcam_1.3M
[ 2.156123] usb 1-1.5: Manufacturer: CN01RH717248726JD80TA00
[ 7.804977] usbcore: registered new interface driver btusb
[ 7.870358] input: Laptop_Integrated_Webcam_1.3M as /devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.5/1-1.5:1.0/input/input12
[ 7.870427] usbcore: registered new interface driver uvcvideo
[ 9.524482] asix 3-2:1.0 eth0: register 'asix' at usb-0000:00:14.0-2, ASIX AX88772B USB 2.0 Ethernet, 00:50:b6:0c:15:e4
[ 9.524515] usbcore: registered new interface driver asix
任何帮助都深表感谢。