如何禁用 USB3 LPM（硬件控制电源管理）？

Question

我在 Ubuntu 16.04 中的 USB3 闪存驱动器有一些问题。它们继续进入 U1/U2 模式（请参阅此处了解更多信息），偶尔会导致 I/O 错误。我已经通过将其放入/etc/rc.local（是的，它是多余的）来禁用传统的（软件控制的）USB 电源管理：

for i in /sys/bus/usb/devices/*/power/autosuspend_delay_ms;
    do echo -1 > $i;
done
for foo in /sys/bus/usb/devices/*/power/control;
    do echo on > $foo;
done

我还尝试了内核引导选项usbcore.autosuspend=-1。但根据dmesg，闪存驱动器仍会继续进入 U1/U2 模式。文档说 USB3 LPM 可以被禁用，/sys/bus/usb/devices/.../(hub interface)/portX/usb3_lpm_permit但我电脑上的任何 USB 设备都不存在这个文件，至少find /sys -iname "*usb3*"没有显示它。在查找内容并显示这些是只读文件：

/sys/devices/pci0000:00/0000:00:14.0/usb2/2-1/power/usb3_hardware_lpm_u1
/sys/devices/pci0000:00/0000:00:14.0/usb2/2-1/power/usb3_hardware_lpm_u2
/sys/devices/pci0000:00/0000:00:14.0/usb2/2-2/power/usb3_hardware_lpm_u1
/sys/devices/pci0000:00/0000:00:14.0/usb2/2-2/power/usb3_hardware_lpm_u2
/sys/devices/pci0000:00/0000:00:14.0/usb2/2-3/power/usb3_hardware_lpm_u1
/sys/devices/pci0000:00/0000:00:14.0/usb2/2-3/power/usb3_hardware_lpm_u2
/sys/devices/pci0000:00/0000:00:14.0/usb2/2-4/power/usb3_hardware_lpm_u1
/sys/devices/pci0000:00/0000:00:14.0/usb2/2-4/power/usb3_hardware_lpm_u2
/sys/devices/pci0000:00/0000:00:14.0/usb2/power/usb3_hardware_lpm_u1
/sys/devices/pci0000:00/0000:00:14.0/usb2/power/usb3_hardware_lpm_u2

前八个包含字符串“启用”，只有最后两个（我猜是集线器）说“禁用”。

如何覆盖此设置并永久禁用所有四个设备的 USB3 LPM？写入这些文件不起作用，我试过了。

这是我的系统信息：HP Chromebox

# lsusb
Bus 002 Device 009: ID 05dc:a838 Lexar Media, Inc. 
Bus 002 Device 006: ID 05dc:a838 Lexar Media, Inc. 
Bus 002 Device 010: ID 05dc:a838 Lexar Media, Inc. 
Bus 002 Device 008: ID 05dc:a838 Lexar Media, Inc. 
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 003: ID 0cf3:311e Atheros Communications, Inc. 
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

核心：

# uname -a
Linux FileserverA112 4.4.0-31-generic #50-Ubuntu SMP Wed Jul 13 00:07:12 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux

# lspci -knn 00:00.0 Host bridge [0600]: Intel Corporation Haswell-ULT DRAM Controller [8086:0a04] (rev 0b) Subsystem: Google, Inc. Haswell-ULT DRAM Controller [1ae0:c000] Kernel driver in use: hsw_uncore 00:02.0 VGA compatible controller [0300]: Intel Corporation Haswell-ULT Integrated Graphics Controller [8086:0a06] (rev 0b) Subsystem: Google, Inc. Haswell-ULT Integrated Graphics Controller [1ae0:c000] Kernel driver in use: i915 Kernel modules: i915 00:03.0 Audio device [0403]: Intel Corporation Haswell-ULT HD Audio Controller [8086:0a0c] (rev 0b) Subsystem: Google, Inc. Haswell-ULT HD Audio Controller [1ae0:c000] Kernel driver in use: snd_hda_intel Kernel modules: snd_hda_intel 00:14.0 USB controller [0c03]: Intel Corporation 8 Series USB xHCI HC [8086:9c31] (rev 04) Subsystem: Google, Inc. 8 Series USB xHCI HC [1ae0:c000] Kernel driver in use: xhci_hcd 00:16.0 Communication controller [0780]: Intel Corporation 8 Series HECI #0 [8086:9c3a] (rev 04) Subsystem: Google, Inc. 8 Series HECI [1ae0:c000] Kernel driver in use: mei_me Kernel modules: mei_me 00:1b.0 Audio device [0403]: Intel Corporation 8 Series HD Audio Controller [8086:9c20] (rev 04) Subsystem: Google, Inc. 8 Series HD Audio Controller [1ae0:c000] Kernel driver in use: snd_hda_intel Kernel modules: snd_hda_intel 00:1c.0 PCI bridge [0604]: Intel Corporation 8 Series PCI Express Root Port 3 [8086:9c14] (rev e4) Kernel driver in use: pcieport Kernel modules: shpchp 00:1c.1 PCI bridge [0604]: Intel Corporation 8 Series PCI Express Root Port 4 [8086:9c16] (rev e4) Kernel driver in use: pcieport Kernel modules: shpchp 00:1c.2 PCI bridge [0604]: Intel Corporation 8 Series PCI Express Root Port 5 [8086:9c18] (rev e4) Kernel driver in use: pcieport Kernel modules: shpchp 00:1f.0 ISA bridge [0601]: Intel Corporation 8 Series LPC Controller [8086:9c45] (rev 04) Subsystem: Google, Inc. 8 Series LPC Controller [1ae0:c000] Kernel driver in use: lpc_ich Kernel modules: lpc_ich 00:1f.2 SATA controller [0106]: Intel Corporation 8 Series SATA Controller 1 [AHCI mode] [8086:9c03] (rev 04) Subsystem: Google, Inc. 8 Series SATA Controller 1 [AHCI mode] [1ae0:c000] Kernel driver in use: ahci Kernel modules: ahci 00:1f.3 SMBus [0c05]: Intel Corporation 8 Series SMBus Controller [8086:9c22] (rev 04) Subsystem: Google, Inc. 8 Series SMBus Controller [1ae0:c000] Kernel modules: i2c_i801 00:1f.6 Signal processing controller [1180]: Intel Corporation 8 Series Thermal [8086:9c24] (rev 04) Subsystem: Google, Inc. 8 Series Thermal [1ae0:c000] 01:00.0 Ethernet controller [0200]: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller [10ec:8168] (rev 0c) Subsystem: Realtek Semiconductor Co., Ltd. RTL8111/8168 PCI Express Gigabit Ethernet controller [10ec:8168] Kernel driver in use: r8169 Kernel modules: r8169 02:00.0 Network controller [0280]: Qualcomm Atheros AR9462 Wireless Network Adapter [168c:0034] (rev 01) Subsystem: Hewlett-Packard Company AR9462 Wireless Network Adapter [103c:1864] Kernel driver in use: ath9k Kernel modules: ath9k

Answer 1

我知道这是一个非常古老的问题，但如果有人仍然感兴趣，我有一个不错的解决方法的指针 - 尽管仍然不是完整的解决方案。自从这个补丁以来，Linux 有一个名为的命令行参数usbcore.quirks，可以在每个设备的基础上禁用 LPM。因此，如果您有一个已知的设备列表（由其 VID 和 PID（由 所示的一对 4 位十六进制数字）标识lsusb）并且希望在不使用 LPM 的情况下使用，请将以下内核参数添加到您的引导加载程序中：

usbcore.quirks=<vid1>:<pid1>:k,<vid2>:<pid2>,k

代表k禁用 LPM，不要问我为什么。您可以列出任意数量的设备。对于问题引用的特定 Lexar Media 闪存驱动器，添加usbcore.quirks=05dc:a838:k- 它将应用于该设备的所有实例。