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From: Wolfram Sang <wsa-z923LK4zBo2bacvFa/9K2g@public.gmane.org>
To: "Peter Hüwe" <PeterHuewe-Mmb7MZpHnFY@public.gmane.org>
Cc: linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
Subject: Re: i2c_transfer & dma
Date: Thu, 25 Sep 2014 16:05:05 +0200	[thread overview]
Message-ID: <20140925140505.GA1316@katana> (raw)
In-Reply-To: <201409232138.33067.PeterHuewe-Mmb7MZpHnFY@public.gmane.org>

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> So the question is - does the user of i2c_transfer have to provide a dma-able 
> buffer, or is the bus driver (like the robotfuzz one) expected to convert 
> incoming buffer into a dma-able buffer?

As of now, this is an open question, sadly. I have a tendency to leave
it to the drivers (maybe with helper functions from the core), because
I2C and DMA is so uncommon. I need to work on I2C & DMA next month
anyhow, so I hope to dive into that topic, too. No promises, though. If
you want to look into it already, please go ahead. The issue was raised
here, too: http://patchwork.ozlabs.org/patch/220137/


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      parent reply	other threads:[~2014-09-25 14:05 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-09-23 19:38 i2c_transfer & dma Peter Hüwe
     [not found] ` <201409232138.33067.PeterHuewe-Mmb7MZpHnFY@public.gmane.org>
2014-09-25 14:05   ` Wolfram Sang [this message]

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