Hi, I fiddled with my BIOS/EFI settings and found the following options related to USB: Legacy USB support: Disabled (was "Enabled" before) Intel xHCI Mode: Enabled (was "Auto" before) EHCI Hand-Off: Disabled (was not changed) Can these setting have any influence on my problem? What are the recommended settings? Moreover the output of "lsusb -v" shows a bunch of messages like get device qualifier: Resource temporarily unavailable can't get debug descriptor: Resource temporarily unavailable What do they mean? What is the correct direction for further investigation? Maybe the following is unrelated to this particular problem, but there are the following messages during boot: [ 0.673165] ACPI Warning: 0x0000000000001828-0x000000000000182f SystemIO conflicts with Region \PMIO 1 (20130725/utaddress-251) [ 0.673176] ACPI: If an ACPI driver is available for this device, you should use it instead of the native driver [ 0.673182] ACPI Warning: 0x0000000000001c30-0x0000000000001c3f SystemIO conflicts with Region \GPIO 1 (20130725/utaddress-251) [ 0.673190] ACPI Warning: 0x0000000000001c30-0x0000000000001c3f SystemIO conflicts with Region \GPRL 2 (20130725/utaddress-251) [ 0.673198] ACPI Warning: 0x0000000000001c30-0x0000000000001c3f SystemIO conflicts with Region \GPR_ 3 (20130725/utaddress-251) [ 0.673206] ACPI: If an ACPI driver is available for this device, you should use it instead of the native driver [ 0.673210] ACPI Warning: 0x0000000000001c00-0x0000000000001c2f SystemIO conflicts with Region \GPIO 1 (20130725/utaddress-251) [ 0.673218] ACPI Warning: 0x0000000000001c00-0x0000000000001c2f SystemIO conflicts with Region \GPRL 2 (20130725/utaddress-251) [ 0.673225] ACPI Warning: 0x0000000000001c00-0x0000000000001c2f SystemIO conflicts with Region \GPR_ 3 (20130725/utaddress-251) [ 0.673232] ACPI: If an ACPI driver is available for this device, you should use it instead of the native driver [ 0.673236] lpc_ich: Resource conflict(s) found affecting gpio_ich Is there any kind of relation between these messages and the USB problem? Perhaps someone could point my in the correct direction what I should do about these messages. Thanks, Matthias Am Mittwoch, 8. April 2015, 18:04:27 schrieb Matthias Nagel: > Am Mittwoch, 8. April 2015, 10:40:39 schrieb Greg KH: > > > > Please send the attachments, no one wants to dig for web links :( > > Here they are. > > > > > This really sounds like some broken hardware as there's nothing that the > > kernel can do to disconnect/reconnect a device like this. Given that > > your hardware works fine in a different machine, I would blame this host > > controller / internal hub / pci board / motherboard / power supply or > > some part of that chain. > > > > I do not believe it is broken a controller/interal hub/pci/etc., because under > Windows everything works fine. There are three scenarios: > > (a) same external USB hardware at a different machine running Linux 3.18.9 --> OK > (b) same external USB hardware at the affected machine running Windows 7 --> OK > (c) same external USB hardware at the affected machine running Linux 3.18.9 --> FAIL > > Due to (a) I know that the devices are supported by Linux. Due to (b) I can exclude a problem with the host controller / internal hub / etc. > > My best guess it that the particular combination of kernel driver and host controller is to blame for the problem. The other machine is rahter old and has only USB 2.0 ports. The affacted machine has a ASUS P9D WS motherboard and a mix of USB 2.0 and 3.0 ports. > > Unfortunately, I am to little of a kernel hacker to investigate the problem any further without external advice. > > Matthias -- Matthias Nagel Parkstraße 27, 76131 Karlsruhe, Deuschland Festnetz: +49-721-96869289, Mobil: +49-151-15998774 e-Mail: matthias.h.nagel@xxxxxxxxx, Skype: nagmat84 -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
