From mboxrd@z Thu Jan  1 00:00:00 1970
From: James Bottomley <James.Bottomley@steeleye.com>
Subject: Re: Proposal for new generic device API: dma_get_required_mask()
Date: 18 Jun 2004 09:19:00 -0500
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	<20040618055909.GA13007@sgi.com>
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To: Jeremy Higdon <jeremy@sgi.com>
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On Fri, 2004-06-18 at 00:59, Jeremy Higdon wrote:
> Sounds good.  But I'm curious why you make the driver call dma_set_mask()
> twice.

Basically so that dma_get_required_mask() returns a value that may be
related to the current mask.  If the device has a wierd mask setting
(say it has bits missing or something), the platform may want to return
something different to tune the required mask to be optimal.

James