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Date: Thu, 2 Sep 2010 14:34:24 -0700
From: "Ira W. Snyder" <iws@ovro.caltech.edu>
To: Sean MacLennan <smaclennan@pikatech.com>
Subject: Re: Where to put board-specific drivers
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On Thu, Sep 02, 2010 at 05:24:34PM -0400, Sean MacLennan wrote:
> On Thu, 2 Sep 2010 14:12:22 -0700
> "Ira W. Snyder" <iws@ovro.caltech.edu> wrote:
> 
> 
> > To give you three example drivers:
> > 1) Data processing FPGA access driver
> > 
> > This driver provides a simple character device to userspace which
> > exposes one function: mmap. With it, you can mmap the entire data
> > processing FPGA memory window into your process. With this, I provide
> > non-realtime FPGA control to userspace applications.
> > 
> > 2) Data processing FPGA capture driver
> > 
> > This driver provides a simple character device to userspace which
> > supports one function: read. Internally, it maintains a list of
> > buffers which hold capture data. When the FPGA's are processing data,
> > they dump data at 64Hz (every 15.625ms). If the data is not copied
> > off the chips before the next dump, data is lost.
> > 
> > DMA is required to move the data volume off the FPGAs fast enough to
> > keep timing. Therefore this really does need to be in-kernel.
> 
> Could these drivers be merged?
> 

I would like to get them merged if possible. I talked with GregKH
several months ago, and he suggested that I should be able to get them
merged, even if I am the only user. They provide a good incentive to get
others who maintain similar drivers out-of-tree to get them merged as
well.

I'll post up the code shortly and let the reviewers tear me to shreds. :)

Thanks for the input,
Ira