Date: Thu, 14 Jun 2007 16:16:45 -0700 From: Alfred Perlstein <alfred@freebsd.org> To: Hans Petter Selasky <hselasky@c2i.net> Cc: freebsd-usb@freebsd.org Subject: Re: HPS USB stack API change Message-ID: <20070614231645.GC96936@elvis.mu.org> In-Reply-To: <200706141156.18290.hselasky@c2i.net>
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* Hans Petter Selasky <hselasky@c2i.net> [070614 02:56] wrote: > Hi all! > > I'm planning to add another argument to "usbd_start_hardware()", which is a > delay value that gives the delay in microseconds or maybe milliseconds before > the transfer is actually queued. This can be used to reduce the polling rate > on BULK-IN transfers among other things, to reduce the overall power usage, > and to safely create infinite polling loops without fearing BUS overusage in > case of failure conditions. > > For example: > > usbd_start_hardware(xfer, 200000); //200 ms delay > > A delay value of zero indicates no delay. > Sounds like a good idea. > I plan to implement this re-using the timeout callout. > > Any comments ? Can't comment as I'm not that familiar with the existing underlying code. -- - Alfred Perlsteinhome | help
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