Skip site navigation (1)Skip section navigation (2)
Date:      Thu, 14 Jun 2007 11:56:18 +0200
From:      Hans Petter Selasky <hselasky@c2i.net>
To:        freebsd-usb@freebsd.org
Subject:   HPS USB stack API change
Message-ID:  <200706141156.18290.hselasky@c2i.net>

next in thread | raw e-mail | index | archive | help
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.

I plan to implement this re-using the timeout callout.

Any comments ?

--HPS



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?200706141156.18290.hselasky>