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From: "Peter Hüwe" <PeterHuewe-Mmb7MZpHnFY@public.gmane.org>
To: linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
Subject: i2c_transfer & dma
Date: Tue, 23 Sep 2014 21:38:32 +0200	[thread overview]
Message-ID: <201409232138.33067.PeterHuewe@gmx.de> (raw)

Hi,

I was wondering if the buffer in an i2c_msg, passed to i2c_transfer must be 
dma-able i.e. dynamically allocated, like for USB?

The reason why I'm asking is because the e.g. the i2c_robotfuzz_osif usb-to-
i2c adapter passes the incoming data directly to a usb_control_msg which of 
course expects the buffer to be dma-able.

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?


Thanks,
Peter

             reply	other threads:[~2014-09-23 19:38 UTC|newest]

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

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