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USB ethernet chip. Adapters that use this chip include the LinkSys USB100TX. There are a few others, but I'm not certain of their availability in the U.S. I used an ADMtek eval board for development. Note that while the ADMtek chip is a 100Mbps device, you can't really get 100Mbps speeds over USB. Regardless, this driver uses miibus to allow speed and duplex mode selection as well as autonegotiation. Building and kldloading the driver as a module is also supported. Note that in order to make this driver work, I had to make what some may consider an ugly hack to sys/dev/usb/usbdi.c. The usbd_transfer() function will use tsleep() for synchronous transfers that don't complete right away. This is a problem since there are times when we need to do sync transfers from an interrupt context (i.e. when reading registers from the MAC via the control endpoint), where tsleep() us a no-no. My hack allows the driver to have the code poll for transfer completion subject to the xfer->timeout timeout rather that calling tsleep(). This hack is controlled by a quirk entry and is only enabled for the ADMtek device. Now, I'm sure there are a few of you out there ready to jump on me and suggest some other approach that doesn't involve a busy wait. The only solution that might work is to handle the interrupts in a kernel thread, where you may have something resembling a process context that makes it okay to tsleep(). This is lovely, except we don't have any mechanism like that now, and I'm not about to implement such a thing myself since it's beyond the scope of driver development. (Translation: I'll be damned if I know how to do it.) If FreeBSD ever aquires such a mechanism, I'll be glad to revisit the driver to take advantage of it. In the meantime, I settled for what I perceived to be the solution that involved the least amount of code changes. In general, the hit is pretty light. Also note that my only USB test box has a UHCI controller: I haven't I don't have a machine with an OHCI controller available. Highlights: - Updated usb_quirks.* to add UQ_NO_TSLEEP quirk for ADMtek part. - Updated usbdevs and regenerated generated files - Updated HARDWARE.TXT and RELNOTES.TXT files - Updated sysinstall/device.c and userconfig.c - Updated kernel configs -- device aue0 is commented out by default - Updated /sys/conf/files - Added new kld module directory |
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