From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeff Garzik Subject: Re: Early ATA devices Date: Wed, 01 Aug 2007 09:47:49 -0400 Message-ID: <46B08F05.9080306@garzik.org> References: <20070801014137.4ab39e94@the-village.bc.nu> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from srv5.dvmed.net ([207.36.208.214]:46384 "EHLO mail.dvmed.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1762813AbXHANrv (ORCPT ); Wed, 1 Aug 2007 09:47:51 -0400 In-Reply-To: <20070801014137.4ab39e94@the-village.bc.nu> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Alan Cox Cc: linux-ide@vger.kernel.org Alan Cox wrote: > #1 We assume identify works. Early ATA actually lists this command > as optional ITYM we assume identify command exists on the device? We certainly do not assume IDENTIFY command, if exists, succeeds. What is the proper probing method -- notice if command-aborted is returned and do something from there? > #2 We don't allow for INIT_DEV_PARAMS failing which it may do on > some early IDE pre ATA devices Suggested handling? Ignore device, since we don't know what state its in, if this fails? > We check ATA < 4 || non-LBA capable when deciding whether to issue > INIT_DEV_PARAMS. ATA 4+ however mandate LBA so the second case isn't > theoretically at least possible. I agree, though I figured that the current code was more robust, in case some weirdo device decided to forget its LBA-ness. No strong opinions here, though. > So in theory we can persuade libata to drive original MFM/RLL disks with > relatively few changes Crazy :) Jeff