Date: Tue, 12 Feb 2008 12:30:50 +0100 From: Bernd Walter <ticso@cicely12.cicely.de> To: freebsd-usb@freebsd.org Subject: Re: Need docs on USB driver development Message-ID: <20080212113049.GE46322@cicely12.cicely.de> In-Reply-To: <20080212010327.GB1054@hades.panopticon> References: <20080211235832.GA1054@hades.panopticon> <20080212010327.GB1054@hades.panopticon>
next in thread | previous in thread | raw e-mail | index | archive | help
On Tue, Feb 12, 2008 at 04:03:27AM +0300, Dmitry Marakasov wrote: > * Dmitry Marakasov (amdmi3@amdmi3.ru) wrote: > > > work through neither uhid nor ugen drivers (though I'm gonna do > > some more digging here). So I've decided to go level lower and write > Upd: I was able to make it work through ugen. By the chance I've plugged > the device into another slot, and it worked. > > So the curious thing is that it works like that: > addr 1: UHCI root hub, Intel > addr 3: AVerMedia USB Radio, AVerMedia Technologies > > (can write commands to /dev/ugen0.2) > > But not like that: > addr 1: OHCI root hub, NEC > addr 2: AVerMedia USB Radio, AVerMedia Technologies > > (writing to /dev/ugen0.2 fails with EIO) Some devices are way to sensitive to noise and sometimes even timing. What you see is very likely a transmission error because of hardware problems and not of software. I would say the device is just badly designed. You may even change the situation by adding an hub between. -- B.Walter http://www.bwct.de http://www.fizon.de bernd@bwct.de info@bwct.de support@fizon.de
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20080212113049.GE46322>