Hi, I have a problem with the USB OTG port on my Beagle Board revision B6 - the OTG port is the only USB port on that device so it's critical that it works. Everybody on this list probably knows this hardware, I'll just say that it has an ARM Cortex-A8 CPU (OMAP3530) with a built-in USB interface. The driver is musb_hdrc. I'm using this interface in host mode (no gadget mode support compiled in, though this doesn't seem to make a difference) to attach necessary peripherals via a powered USB hub. The make and model of hub do not play a role, I've tried several. The problem: Whenever the following conditions are met all hardware on the port "disappears" after a few minutes, cutting off the board from network and storage: - Network traffic over USB (doesn't matter if it's regular 100 Mbps Ethernet or a WLAN stick) - Disk "traffic" over USB - I use a 2,5" disk in a USB enclosure - CPU load - not sure if this is necessary The only fix seems to be a reboot. This happens to me when compiling something on the board (easier than cross-compiling) with the help of Icecream, which is a kind of distcc on steroids. On #beagle on Freenode IRC I've found somebody with the same problem when scp-ing a large file (several hundred megabytes) off or onto the USB disk. I can reproduce that as well. I have spent a lot of time trying to find fixes and/or workarounds but nothing worked so far except using the "validation kernel" recommended to test the hardware e.g. after receipt: http://code.google.com/p/beagleboard/wiki/BeagleBoardDiagnostics. Fittingly, the link to the kernel image is currently broken. The board usually locked itself up after about a day when using that ancient kernel, so it's not an option either, and probably quite unmaintained and buggy in many other areas. So far I have tried many versions of the linux-omap and linux-omap-pm kernel, from about 2.6.30 to the latest git version. They all exhibit the USB OTG death bug. I've used kernels with openembedded patches and without, currently without. Yesterday I discovered the musb_hdrc.fifo_mode parameter and played around with it. I also modified the given configurations. Result: - FIFO configurations including .mode = BUF_DOUBLE don't work at all - no devices work. - the USB death bug is not fixed by: - using only one endpoint - using no TXRX entries but only separate RX and TX (every endpoint gets a TX and an RX entry though) - using a large number of endpoints with same maxpacket value ... still no solution. Enabling debug output of the musb_hdrc driver (yes I've also compiled in debug messages) is not very practical due to the high volume of messages; also, when the bug occurs nothing special is printed. The first error usually comes from the memory manager / filesystem complaining that it can't do "IO to offline device", i.e. the disappeared external harddisk (which contains the swapfile). I would *really* appreciate somebody looking into this because this currently makes the hardware as useful as a brick for me. I can supply debug output and test patches. Cheers, Andreas -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
