Re: [PATCH] Add SPI over GPIO driver

From: Michael Buesch
Date: Tue Jul 15 2008 - 09:05:55 EST


On Tuesday 15 July 2008 07:30:51 Ben Nizette wrote:
> Looks good overall. I'm not sure that it need pretend to be
> hotpluggable though

Because the hardware _is_ hotpluggable.

> (i.e. the board info can be hardwired so there's no
> need for the board setup callback).

I'm not sure why we should limit ourselves so much by compiling
dynamic and completely individual information, like the bus
wireing into the kernel.
This _has_ to be dynamic, as the wireing is _completely_ random and
different for every machine. This is selfmade hardware. ;)

> What problem are you solving (or whole in board support are you
> plugging) in this dynamic plugging of MMCs?

This is to support running MMCs/SDs on GPIO pins.
Which board or card provides the GPIO pins doesn't matter. It doesn't
matter, as it's completely abstracted. You can even run 10 or more
of the cards at the same time, if you have enough GPIO pins.

Of course, this is mostly useful for embedded systems only.
But it is not bound to any specific type of hardware. The hardware just
has to implement generic GPIO for its GPIO pins.

--
Greetings Michael.
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