Re: [PATCH] i2c: mxs: Add PIO and mixed-DMA support

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Hi Wolfram,

> On Thu, Nov 22, 2012 at 01:50:37AM +0100, Marek Vasut wrote:
> > Dear Marek Vasut,
> > 
> > > Add support for the PIO mode and mixed PIO/DMA mode support. The mixed
> > > PIO/DMA is the default mode of operation. This shall leverage overhead
> > > that the driver creates due to setting up DMA descriptors even for very
> > > short transfers.
> > > 
> > > The current boundary between PIO/DMA 8 bytes, transfers shorter than 8
> > > bytes are transfered by PIO, longer transfers use DMA. The performance
> > > of write transfers remains unchanged, while there is a minor
> > > improvement of read performance. Reading 16KB EEPROM with DMA-only
> > > operations gives a read speed of 39.5KB/s, while with then new
> > > mixed-mode the speed is blazing 40.6KB/s.
> > > 
> > > Signed-off-by: Marek Vasut <marex@xxxxxxx>
> > > Cc: Fabio Estevam <fabio.estevam@xxxxxxxxxxxxx>
> > > Cc: Shawn Guo <shawn.guo@xxxxxxxxxx>
> > > Cc: Wolfram Sang <w.sang@xxxxxxxxxxxxxx>
> > 
> > [...]
> > 
> > btw. Wolfram, you might want to drop me some credit into the MX28 i2c
> > driver, I suspect most of the code in there is mine now anyway :-D
> 
> It's fine if you do this yourself.

I don't see this patch in -next ... or am I looking wrong?

Best regards,
Marek Vasut
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