Alan Stern <stern@...> writes: > > [Moving this discussion to the linux-usb mailing list since it no > longer has anything to do with libusb. For those who want to catch up, > see > > http://marc.info/?t=130866132200001&r=1&w=2 > > and especially > > http://marc.info/?l=libusb-devel&m=130885548606176&w=2 > http://marc.info/?l=libusb-devel&m=130886315416247&w=2 > > In short, the EHCI controller on this OMAP board sometimes (once every > 10 or 20 attempts) stops working after an unlink. The MUSB OTG > controller works okay in host mode.] > > Ed: > > There's some more debugging you can do. After one of these failures, > mount a debugfs filesystem on /sys/kernel/debug and go to the > /sys/kernel/debug/usb/ehci/ehci-omap.0 directory. Let's see what the > "registers" file contains. > > Alan Stern > > -- > To unsubscribe from this list: send the line "unsubscribe linux-usb" in > the body of a message to majordomo@... > More majordomo info at http://vger.kernel.org/majordomo-info.html > > Here is a look at the registers in two cases as specified below for comparison: #### After failure (device was disconnected, but still shows up in lsusb) ##### # lsusb Bus 001 Device 001: ID 1d6b:0002 Bus 002 Device 001: ID 1d6b:0002 Bus 002 Device 002: ID 0424:2513 Bus 002 Device 007: ID 05ac:1266 # mount -t debugfs debugfs /sys/kernel/debug/ # cd /sys/kernel/debug/usb/ehci/ehci-omap.0 # cat registers bus platform, device ehci-omap.0 OMAP-EHCI Host Controller EHCI 1.00, hcd state 1 structural params 0x00001313 capability params 0x00000016 status 4008 Periodic FLR command 010019 (park)=0 ithresh=1 Periodic period=256 RUN intrenable 37 IAA FATAL PCD ERR INT uframe 2d2a port 1 status 001005 POWER sig=se0 PE CONNECT port 2 status 001000 POWER sig=se0 port 3 status 001000 POWER sig=se0 irq normal 222 err 70 reclaim 180 (lost 0) complete 290 unlink 26 #### After subsequent reboot, but prior to any device connect/disconnect ##### # lsusb Bus 001 Device 001: ID 1d6b:0002 Bus 002 Device 001: ID 1d6b:0002 Bus 002 Device 002: ID 0424:2513 # mount -t debugfs debugfs /sys/kernel/debug/ # cd /sys/kernel/debug/usb/ehci/ehci-omap.0 # cat registers bus platform, device ehci-omap.0 OMAP-EHCI Host Controller EHCI 1.00, hcd state 1 structural params 0x00001313 capability params 0x00000016 status 4008 Periodic FLR command 010019 (park)=0 ithresh=1 Periodic period=256 RUN intrenable 37 IAA FATAL PCD ERR INT uframe 2daf port 1 status 001005 POWER sig=se0 PE CONNECT port 2 status 001000 POWER sig=se0 port 3 status 001000 POWER sig=se0 irq normal 17 err 0 reclaim 5 (lost 0) complete 16 unlink 0 -- 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
