Hi Apologies if this is the incorrect place to post this, if so please feel free to call me names and then suggest somewhere more appropriate :)
We have an embedded device on an old EPIA Mini-ITX board that runs Linux 2.6. There are features in more recent (>3.10) kernels that would be useful to us, so I tried to build them for it; however while the kernel runs perfectly fine, ehci support simply fails, which is catastrophic for the device's use - we need USB2 speeds. I worked backwards and found that it runs normally on 3.7.9, but on 3.7.10 it starts throwing up errors: usb 1-5: new high-speed USB device number 3 using ehci_hcd usb 1-5: device descriptor read/8, error -110 usb 1-5: device descriptor read/8, error -110 usb 1-5: new high-speed USB device number 4 using ehci_hcd usb 1-5: device not accepting address 4, error -110 usb 1-5: new high-speed USB device number 5 using ehci_hcd By 3.8.0 ehci simply doesn't work, as if someone decided these errors were too hard to deal with and just disabled the device support. Chipset is VIA vt82xxx; the ID of the offending bus is 1106:3104 I tried every combination of loading ehci before and after etc, setting the old_scheme_first value, disabling acpi/apm, basically anything I could find on the web that seems related to ehci problems, but nothing seems to make the ehci driver even recognise the device. /proc/bus/pci/devices shows 0000 11063123 0 e6000008 0 0 0 0 0 0 400000 0 0 0 0 0 0 agpgart-via 0008 1106b091 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0080 11063038 c 0 0 0 0 d001 0 0 0 0 0 0 20 0 0 uhci_hcd 0081 11063038 c 0 0 0 0 d401 0 0 0 0 0 0 20 0 0 uhci_hcd 0082 11063038 5 0 0 0 0 d801 0 0 0 0 0 0 20 0 0 uhci_hcd 0083 11063104 9 e6400000 0 0 0 0 0 0 100 0 0 0 0 0 0 0088 11063177 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0089 11060571 0 1f0 3f6 170 376 dc01 0 0 8 0 8 0 10 0 0 VIA_IDE 008d 11063059 5 e001 0 0 0 0 0 0 100 0 0 0 0 0 0 snd_via82xx 0090 11063065 c e801 e6401000 0 0 0 0 0 100 100 0 0 0 0 0 via-rhine 0100 11063122 c e0000008 e4000000 0 0 0 0 c0002 4000000 1000000 0 0 0 0 20000 (apologies for the long lines, I cut down the spacing as much as I could). So you can see that the 11063104 line doesn't even have the ehci-hcd driver associated; on earlier kernel versions the line reads 0083 11063104 9 e6400000 0 0 0 0 0 0 100 0 0 0 0 0 0 ehci_hcd Output from lsmod, just in case you're thinking I just haven't inserted the ehci driver... usbnet 10726 0 - Live 0xcfb4f000 ohci_hcd 15520 0 - Live 0xcfad9000 uhci_hcd 15679 0 - Live 0xcfa94000 ehci_hcd 30853 0 - Live 0xcfa49000 pl2303 6016 0 - Live 0xcf979000 ftdi_sio 25410 0 - Live 0xcf940000 option 18882 0 - Live 0xcf8e7000 usb_wwan 4082 1 option, Live 0xcf8a2000 I'm happy to dig for myself - I appreciate this is a fairly niche problem; I have getting on for 30 years' development experience in various platforms, including low-level hardware access in assembly when I was young, but all I've ever done with the kernel is modify in a very small way a few device drivers and I don't even know where to start with this so could do with some pointers. I tried running a diff on drivers/usb between 3.7.9 and 3.7.10, but other than a few changes around usbserial there doesn't seem to be much, which seems odd given that the behaviour clearly changed. The 3.7.10 changelog only lists some usb-audio changes, a change for memory allocation for some urb blocks, and some fixes for usb-serial, so I guess something else changing has modified the way the USB core interacts with the hardware. Did we intentionally simply drop support for this chipset in 3.8? Thanks! Geoff
