From owner-freebsd-hackers Thu Oct 2 17:41:15 1997 Return-Path: Received: (from root@localhost) by hub.freebsd.org (8.8.7/8.8.7) id RAA05055 for hackers-outgoing; Thu, 2 Oct 1997 17:41:15 -0700 (PDT) Received: from sendero-ppp.i-connect.net (sendero-ppp.i-Connect.Net [206.190.143.100]) by hub.freebsd.org (8.8.7/8.8.7) with SMTP id RAA05007 for ; Thu, 2 Oct 1997 17:41:08 -0700 (PDT) Received: (qmail 14176 invoked by uid 1000); 3 Oct 1997 00:41:25 -0000 Message-ID: X-Mailer: XFMail 1.2-alpha-092597 [p0] on FreeBSD X-Priority: 3 (Normal) Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 8bit MIME-Version: 1.0 In-Reply-To: Date: Thu, 02 Oct 1997 17:41:25 -0700 (PDT) Organization: Atlas Telecom From: Simon Shapiro To: "Jamil J. Weatherbee" Subject: RE: Device drivers Cc: hackers@FreeBSD.ORG Sender: owner-freebsd-hackers@FreeBSD.ORG X-Loop: FreeBSD.org Precedence: bulk Hi "Jamil J. Weatherbee"; On 02-Oct-97 you wrote: > > > I've taken a look at the source code to a few device drivers and run the > example scripts for Isa stuff, I have a general feeling of what needs to > be in one and how it operates however I simply don't feel I have enough > information (or a well enough documented example) to feel confident > writing one myself, does anyone have a document/FAQ no matter how small > describng the required functions/tables/probing /irq setup etc. so I > would > know what exactly I am doing. A line by line walk through of even a > cheeseball driver would be greatly appreciated or perhaps even a pointer > to a well documented driver (My standard is to have a comment on every > line of code, that's what I mean by "well documented"), but preferably > not > to lengthy where I am goin to mostly be looking at the nitty gritty of a > device I don't know about or understand. Someone passed me a driver for > a > stepper motor, the idea of what it is doing with the physical hardware > is > easy for me since I deal with that stuff all the time, unfortunately > there > are hardly no comments. Being new to FreeBSD drivers, I can appreciate your desire. Grab the dlm patch from ftp://ftp.i-connect.net/crash. It contains both the DLM (very, very alpha) and the DPT driver. There is also a paid of matching design papers. They are not great but do contain a description of the flow. The DPT driver is actualy two drivers. One is a SCSI Host Bus Adapter, and one is a character decive driver. They are both documented and hopefully readable. For SCSI only, try Justin's ahc driver. --- Sincerely Yours, Simon Shapiro Atlas Telecom Senior Architect 14355 SW Allen Blvd., Suite 130 Beaverton OR 97005 Shimon@i-Connect.Net Voice: 503.799.2313