From owner-freebsd-hackers Sat Jun 20 07:26:10 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id HAA26095 for freebsd-hackers-outgoing; Sat, 20 Jun 1998 07:26:10 -0700 (PDT) (envelope-from owner-freebsd-hackers@FreeBSD.ORG) Received: from soleil.uvsq.fr (soleil.uvsq.fr [193.51.24.1]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id HAA26086 for ; Sat, 20 Jun 1998 07:26:00 -0700 (PDT) (envelope-from son@cezanne.prism.uvsq.fr) Received: from cezanne.prism.uvsq.fr (rtc102.reseau.uvsq.fr [193.51.24.18]) by soleil.uvsq.fr (8.8.8/jtpda-5.3) with ESMTP id QAA26804 ; Sat, 20 Jun 1998 16:25:55 +0200 (METDST) Received: (from son@localhost) by cezanne.prism.uvsq.fr (8.8.8/8.8.5) id MAA02181; Sat, 20 Jun 1998 12:06:06 GMT Message-ID: <19980620120606.44000@breizh.prism.uvsq.fr> Date: Sat, 20 Jun 1998 12:06:06 +0000 From: Nicolas Souchu To: Peter Dufault Cc: freebsd-hackers@FreeBSD.ORG, mbouget@club-internet.fr Subject: Re: I2C bus References: <19980609234406.41618@breizh.prism.uvsq.fr> <199806141757.NAA07458@hda.hda.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 0.81e In-Reply-To: <199806141757.NAA07458@hda.hda.com>; from Peter Dufault on Sun, Jun 14, 1998 at 01:57:48PM -0400 X-Operating-System: FreeBSD breizh 3.0-CURRENT FreeBSD 3.0-CURRENT Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG On Sun, Jun 14, 1998 at 01:57:48PM -0400, Peter Dufault wrote: >> We're about to write Philips semiconductor support for the I2C bus. > >I put my latest code up on incoming where the incoming elves will >move it someplace else and I guess tell us. Look for "i2c.tgz" >dated June 14. Ok, thanks. > >This code will be the basis for a FreeBSD driver for boards/systems >based on the Philips controller chip that I'll be putting together >real soon, well, as soon as that problem bubbles to the top of my >priority list, hopefully this month. Will see how to merge our efforts. > >If someone is interested in working toward a bit-banging (i.e., >line printer port etc) implementation then they should look at the >i2cslave code in that tar ball and consider what it would take to >make a non-blocking state driven master similar to the non-blocking >state driven slave that it now implements. What would be the purpose of such a driver in kernel? Polling takes all the cpu. We'd like rather have the PCF8584 connected to the parallel port. > >I'm not going to have a lot of time to work on this, so I'll be >changing this for my needs. Specifically, I plan on changing the >current i2c.c Philips code to a reentrant interrupt driven driver >with the slave address encoded in the device minor number. I'll >keep in the back of my mind the idea that someone may want to splice >in the bit banging code, so I'll modify the current compile time >selection to be member-function table driven. We're working currently on this part to support IP over I2C. > >This is not the greatest code since it has always been developed >specifically to meet my needs. However, it is wrung out, has run >in several environments over the last 5 or 6 years, and is solid >from the point of view of timing. > >Enjoy - Thanks for your contribution. > >Peter > >-- >Peter Dufault (dufault@hda.com) Realtime development, Machine control, >HD Associates, Inc. Safety critical systems, Agency approval > -- Nicolas.Souchu@prism.uvsq.fr FreeBSD - Turning PCs into workstations - http://www.FreeBSD.org To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message