[PATCH 1/8] Documentation/spi/spidev_test.c: use one rx buffer
stillcompiling at gmail.com
Tue Nov 17 10:58:54 PST 2015
On Tuesday, November 17, 2015 05:41:56 PM Mark Brown wrote:
> On Tue, Nov 17, 2015 at 07:24:21AM -0800, Joshua Clayton wrote:
> > default_rx and rx are needlessly different.
> > Use one buffer, local to transmit()
> Why? This isn't what I'd expect from black boxing the API, from a
> userspace point of view the transfer is atomic and in an ideal world
> we'd be able to do direct to/from memory transfers rather than memcpy()
> into kernel space which means that userspace should assume the transfers
> are going on simultaneously even if they don't currently.
The important thing here was to get rid of the default_rx buffer.
I just noticed that the output can be set up completely within the scope
of the transmit function, since the operands are global. But I would be
just as happy to set it up at the top level. I'll change this in V2
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