Date: Thu, 13 Mar 2003 09:00:33 -0800 (PST) From: Henning Meier-Geinitz <henning@meier-geinitz.de> To: freebsd-bugs@FreeBSD.org Subject: Re: kern/41281: USB scanning works only once Message-ID: <200303131700.h2DH0XN3047258@freefall.freebsd.org>
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The following reply was made to PR kern/41281; it has been noted by GNATS. From: Henning Meier-Geinitz <henning@meier-geinitz.de> To: Nate Lawson <nate@root.org> Cc: freebsd-gnats-submit@freebsd.org Subject: Re: kern/41281: USB scanning works only once Date: Thu, 13 Mar 2003 17:58:14 +0100 Hi, On Wed, Mar 12, 2003 at 09:30:16PM -0800, Nate Lawson wrote: > Please send me a pointer to the relevant code in the linux driver and I > may be able to put together a workaround. Well, the problem is that there is no special code in the Linux kernel for working-around the problem. My observation is that the Linux kernel invokes functions that change the USB toggle (e.g. set_configuration) only on driver load/plugging in the device. BSD seems to change the toggle on every open() (and/or close()?) of a USB device file. That's not wrong, it just triggers this hardware bug. I don't know the FreeBSD kernel internals but I gues it's not easy to work around this bug without changing the way how USB is handled in general. E.g. set_configuration in Linux is only called in usb_new_device() (drivers/usb/core/usb.c) which is called by the hub driver on device connect. That's with linux 2.5.64. Bye, Henning To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-bugs" in the body of the message
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