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Date: Sun, 09 Jul 2006 12:29:10 -0400
From: Jeff Garzik <jeff@garzik.org>
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To: Alan Cox <alan@lxorguk.ukuu.org.uk>
CC: Andrew Morton <akpm@osdl.org>, Reuben Farrelly <reuben-lkml@reub.net>,
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       rdunlap@xenotime.net, greg@kroah.com, john stultz <johnstul@us.ibm.com>,
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       "linux-ide@vger.kernel.org" <linux-ide@vger.kernel.org>
Subject: Re: 2.6.18-rc1-mm1
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Alan Cox wrote:
> The old drivers/ide code uses much longer delays than the spec for some
> ATAPI commands, and it looks as if there is a good reason for doing
> so ...


FWIW, the code that ATADRVR (http://www.ata-atapi.com/) uses to issue 
commands does something like

	write Command register to start command
	if (device == ATAPI)			# i.e. not ATA
		delay(150 msec)
	pound Status / AltStatus, kick DMA engine, whatever else

ATADRVR is open code (for an MS-DOS-level driver), and really worth a 
read.  Between ATADRVR and drivers/ide, you get a pretty good idea about 
what __field experience__ has shown is needed for ATAPI devices.

	Jeff