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To: John-Mark Gurney <gurney_j@resnet.uoregon.edu>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
In-Reply-To: Your message of "Tue, 05 Sep 2006 10:33:35 MST."
	<20060905173334.GH9421@funkthat.com> 
Date: Tue, 05 Sep 2006 17:44:48 +0000
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Cc: freebsd-current@FreeBSD.org, freebsd-drivers@FreeBSD.org,
	freebsd-arch@FreeBSD.org
Subject: Re: bus_get_dma_tag now necessary for drivers using bus_dma 
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In message <20060905173334.GH9421@funkthat.com>, John-Mark Gurney writes:

>This means that for each call to bus_dma_tag_create, instead of passing
>a NULL pointer, you should call bus_get_dma_tag(yourdev) and use that
>as the parent tag.  I committed some example code to various drivers,
>such as ahc, ata, em, and ohci.

If there are never any exeptions to this requirement, why not
pass "yourdev" and have the magic hidden, rather than add 17
ritual characters to the API ?

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.