[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Old Index]
Preparing to write new USB Host Controller driver
I'm preparing to write a driver for SUBWAY USB controller. It is
intended to be used with Amiga 1200 (and some compatible clockports). SUBWAY is
based on TransDimensions/Oxford UHC124 chip, which is a low-cost, non-PCI
USB host controller for embedded applications.
This topic was discussed briefly on port-amiga list, where kind guys
explained me how to interface properly to subsystems of Amiga port. Driver will
be split into MI driver for UHC124, and Amiga-specific frontend for SUBWAY.
As UHC124 does not support OHCI/UHCI, I need to write my own interface
to USB stack. This looks a bit... complicated. It was already done in SL811HS
driver, but implementation is a bit unclear to me. Looks like there are some
ugly hacks. For example NetBSD's USB stack assumes that Host Controller is DMA
capable - and UHC124 is not capable of DMA transfers. DMA was "faked" by
SL811HS driver. Is this the proper way to resolve the problem?
Driver skeleton: http://c0ff33.net/svn/netbsd-subway/src/sys/ .
Main Index |
Thread Index |