Hi, please see my comment below. It might be helpful for some of you.
On Thursday 28 August 2008 23:11:51 Steven A. Falco wrote: > Alan Stern wrote: > > Your original post mentioned that the 440EPx has only one USB 2.0 host > > port. Then how can you use a keyboard and memory stick at the same > > time? You'd have to plug them into a hub -- in which case only one > > controller would be needed, the one driving the hub. The patch would > > be unnecessary. > > I have one of these processors on a Sequoia board. What happens is that > if you build the kernel with both EHCI and OHCI support, then plug in > a modern USB memory stick, it initially tries EHCI, the driver fails, and > the whole thing falls back to OHCI. So you wind up running at 12 Mbps. > The only way to make high speed work is to turn off the OHCI driver, and > then you cannot support slow devices with that kernel. There is a simple trick to get all types (full, low ang high speed) of devices work: use a USB hub with transaction translators. We are doing so on a custom design based on the 440EPx. So we only build the kernel with EHCI support and there was no need for this ugly hack. > > So, hile you cannot plug two devices in at one time, you can plug in > different speed devices at different times, and my understanding is that > this patch will let that work seamlessly. That's true. Matthias _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-dev