On Mon, 14 Apr 2014 stefani@xxxxxxxxxxx wrote: > > From Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>: > > > On Sun, 13 Apr 2014, Stefani Seibold wrote: > > > >> When executing a kexec kernel on a PowerPC board the new started kernel > >> will not find already enumerated USB devices due a missing reset on the > >> USB bus. > > > > How do you know the problem is caused by a missing reset? > > > > A "echo 1 >/sys/bus/pci/drivers/ehci-pci/0000\:00\:17.2/reset" will > solve this for kernel 3.10. So i thought this is a reset problem. All that means is the problem can be fixed by adding a reset. It doesn't mean that the problem was caused by a missing reset. > But i have now a kernel 3.14 running on my PowerPC device and this > have a different behavour. After a couple of minutes the USB device > will appear again. > > > Can you post the dmesg log from the kexec-ed kernel, with > > CONFIG_USB_DEBUG enabled? > > > > Here is the log for a 3.14 which CONFIG_USB_DEBUG enabled: > <6>[ 2.308009] usb 1-2: New USB device found, idVendor=0424, idProduct=2514 > <6>[ 2.318509] usb 1-2: New USB device strings: Mfr=0, Product=0, > SerialNumber=0 > <6>[ 2.327340] hub 1-2:1.0: USB hub found > <6>[ 2.331579] hub 1-2:1.0: 4 ports detected This device worked okay. > <6>[ 2.707176] usb 1-4: new high-speed USB device number 4 using ehci-pci > <3>[ 17.823176] usb 1-4: device descriptor read/64, error -110 > <3>[ 33.043207] usb 1-4: device descriptor read/64, error -110 > <6>[ 33.263185] usb 1-4: new high-speed USB device number 5 using ehci-pci > <3>[ 48.379210] usb 1-4: device descriptor read/64, error -110 > <3>[ 63.607205] usb 1-4: device descriptor read/64, error -110 > <6>[ 63.827191] usb 1-4: new high-speed USB device number 6 using ehci-pci > <3>[ 68.851401] usb 1-4: device descriptor read/8, error -110 > <3>[ 73.975374] usb 1-4: device descriptor read/8, error -110 > <6>[ 74.203206] usb 1-4: new high-speed USB device number 7 using ehci-pci > <3>[ 79.231446] usb 1-4: device descriptor read/8, error -110 > <3>[ 84.359422] usb 1-4: device descriptor read/8, error -110 > <3>[ 84.475224] hub 1-0:1.0: unable to enumerate USB device on port 4 Is this the problem you are referring to? > <6>[ 84.795211] usb 2-2: new full-speed USB device number 2 using ohci-pci > <6>[ 85.016582] usb 2-2: New USB device found, idVendor=0451, idProduct=2036 > <6>[ 85.023394] usb 2-2: New USB device strings: Mfr=0, Product=1, > SerialNumber=0 > <6>[ 85.030572] usb 2-2: Product: General Purpose USB Hub > <6>[ 85.043722] hub 2-2:1.0: USB hub found > <6>[ 85.049569] hub 2-2:1.0: 2 ports detected > <6>[ 85.367220] usb 3-2: new full-speed USB device number 2 using ohci-pci > <3>[ 100.555212] usb 3-2: device descriptor read/64, error -110 > <3>[ 115.847196] usb 3-2: device descriptor read/64, error -110 > <6>[ 116.131178] usb 3-2: new full-speed USB device number 3 using ohci-pci > <3>[ 131.311178] usb 3-2: device descriptor read/64, error -110 > <3>[ 146.595209] usb 3-2: device descriptor read/64, error -110 > <6>[ 146.887192] usb 3-2: new full-speed USB device number 4 using ohci-pci > <3>[ 151.915584] usb 3-2: device descriptor read/8, error -110 > <3>[ 157.039436] usb 3-2: device descriptor read/8, error -110 > <6>[ 157.323180] usb 3-2: new full-speed USB device number 5 using ohci-pci > <3>[ 162.352239] usb 3-2: device descriptor read/8, error -110 > <3>[ 167.484079] usb 3-2: device descriptor read/8, error -110 > <3>[ 167.591236] hub 3-0:1.0: unable to enumerate USB device on port 2 And this? > <6>[ 167.936921] usb 2-2.1: new full-speed USB device number 3 using ohci-pci > <6>[ 168.067890] usb 2-2.1: New USB device found, idVendor=076b, > idProduct=a021 > <6>[ 168.074871] usb 2-2.1: New USB device strings: Mfr=1, Product=2, > SerialNumber=0 > <6>[ 168.082226] usb 2-2.1: Product: Smart Card Reader > <6>[ 168.086963] usb 2-2.1: Manufacturer: USB > <6>[ 168.172893] usb 2-2.2: new low-speed USB device number 4 using ohci-pci > <6>[ 168.300839] usb 2-2.2: New USB device found, idVendor=0aad, > idProduct=0024 > <6>[ 168.307823] usb 2-2.2: New USB device strings: Mfr=1, Product=2, > SerialNumber=0 > <6>[ 168.315180] usb 2-2.2: Product: FrontPanel USB Keyboard > <6>[ 168.320436] usb 2-2.2: Manufacturer: Rohde&Schwarz > <6>[ 168.337895] input: Rohde&Schwarz FrontPanel USB Keyboard as > /devices/pci0000:00/0000:00:17.0/usb2/2-2/2-2.2/2-2.2:1.0/input/input0 > <6>[ 168.360988] input: Rohde&Schwarz FrontPanel USB Keyboard as > /devices/pci0000:00/0000:00:17.0/usb2/2-2/2-2.2/2-2.2:1.1/input/input1 Since some devices work and some don't, maybe part of the problem lies in the particular devices. > This is the output of lsusb: > > Bus 001 Device 002: ID 0424:2514 Standard Microsystems Corp. USB 2.0 Hub > Bus 001 Device 004: ID 0928:0007 Oxford Semiconductor, Ltd > Bus 002 Device 002: ID 0451:2036 Texas Instruments, Inc. TUSB2036 Hub > Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub > Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub > Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub > Bus 002 Device 003: ID 076b:a021 OmniKey AG CCID Smart Card Reader > Bus 002 Device 004: ID 0aad:0024 Rohde & Schwarz GmbH & Co. KG > > My old kernel 3.4 does not show this problem. Since kernel 3.10 i need > to reset to ehci-pci device when kexec. But this workaround does not > work any longer on kernel 3.14. Have you tried bisecting between 3.4 and 3.10 to find which commit caused the behavior to change? What about if you just do: rmmod ehci-pci modprobe ehci-pci Alan Stern -- 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
