Questions like this should always be sent to the linux-usb mailing list. On Sun, 11 Sep 2016, Arun Thiruvanantha wrote: > Hi Alan, > I am working some USB driver Issue that when we do several reload , USB > device is not detected . What do you mean by "reload"? What kernel version are you using? > *These below logs are missing:* What do you mean? If they are missing, how were you able to copy them into your email? > usb 2-1: New USB device found, idVendor=8087, idProduct=0020 > usb 2-1: New USB device strings: Mfr=0, Product=0, SerialNumber=0 > usb 2-1: configuration #1 chosen from 1 choice > hub 2-1:1.0: USB hub found > hub 2-1:1.0: 6 ports detected > ata5: SATA link down (SStatus 0 SControl 310) > usb 2-1.1: new high speed USB device number 3 using ehci_hcd > usb 2-1.1: New USB device found, idVendor=0e39, idProduct=2f00 > usb 2-1.1: New USB device strings: Mfr=1, Product=2, SerialNumber=3 > usb 2-1.1: Product: EUSB > usb 2-1.1: Manufacturer: SMART > usb 2-1.1: SerialNumber: STP19220K2H > usb 2-1.1: configuration #1 chosen from 1 choice > usb 2-1.4: new high speed USB device number 4 using ehci_hcd > usb 2-1.4: New USB device found, idVendor=136b, idProduct=0003 > > *We have Workaround fix for that :* > > echo -n "0000:00:1d.0" > /sys/bus/pci/drivers/ehci_hcd/unbind > > echo -n "0000:00:1d.0" > /sys/bus/pci/drivers/ehci_hcd/bind > > Also I seen some post in forum that increase reset timeout as 100 . > > > https://groups.google.com/forum/#!topic/fa.linux.kernel/7T_ahq-zEbc > > https://lkml.org/lkml/2014/4/14/958 > > ehci->reset_done [wIndex] = jiffies > > ! + msecs_to_jiffies (100); > > } > > ehci_writel(ehci, temp, status_reg); > > break; > > > Issue is not there with 100 ms, Do Have any proper fix in kernel ? I can't tell because I don't know what kernel version you are using. However, the current kernel version uses 50 ms for root-hub port resets. This is what the USB-2.0 specification requires (section 7.1.7.5). > We need proper fix without workaround fix. > > Please help me > > Thanks Please run a test with debugging enabled. This means you should do: echo module ehci_hcd =p >/sys/kernel/debug/dynamic_debug/control before starting the test. What shows up in the dmesg log when you do this? 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
