FT4232H on ehci problem (was Re: usb/143832: [uftdi] Request support for FTDI FT4232H.)

[UEMURA Tetsuya]

Posted on Mon, 15 Feb 2010 15:06:14 +0100
by author Hans Petter Selasky <hselasky at c2i.net>
> On Monday 15 February 2010 15:00:56 Hans Petter Selasky wrote:
> > On Monday 15 February 2010 14:37:10 UEMURA Tetsuya wrote:
> > > > Now I have a problem with the device. When it is attached on ehci, it
> > > > always stalls when I do a bit heavy communication over it. This doesn't
> > > > happen with uhci (kldunload ehci or whatever).
> > >
> > > I did further investigation myself and found that wMaxPacketSize is
> > > 0x0200 when the device was on ehci (0x0040 on uhci), and the device
> > > seemed to work (at least not stall) on ehci if I changed
> > > UFTDI_[IO]BUFSIZE to 512.
> > >
> > > The device however stopped working on uhci with such a modification.
> > >
> > > By the way, the official FTDI Linux driver found at
> > > http://www.ftdichip.com/Drivers/VCP/Linux/ftdi_sio.tar.gz
> > > also seemed to specify 512 as its buffer sizes.
> > >
> > > Can anyone help me?
> > >
> > > Regards.
> > 
> > What platform are you running?

Hi Hans.

It's a recent 8-STABLE.  Full dmesg output and level 5 (or maybe level
10) usb log can be found at the following location.
http://lists.freebsd.org/pipermail/freebsd-usb/2010-February/008293.html

> There is a special feature in the new USB stack. Try to define:
> 
> #define UFTDI_IBUFSIZE 0  /* use wMaxPacketSize */

Thanks. I'll test it tomorrow.

Regards.

-- 
UEMURA Tetsuya <t_uemura at macome.co.jp>