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Subject: spi-oc-tiny.c and microwatt chip select
From:   Benjamin Herrenschmidt <benh@kernel.crashing.org>
To:     Mark Brown <broonie@kernel.org>
Cc:     linux-spi@vger.kernel.org
Date:   Sat, 06 Jun 2020 18:50:37 +1000
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Hi !

I've cooked up a little SPI controller VHDL for the Microwatt project
(https://github.com/antonblanchard/microwatt, though the SPI isnt
merged yet), to control the flash connected to the FPGA (it contains
the bitfile and the SW payload, such as Linux).

Now I could write yet-another bitbang driver for Linux for it, or I
could make my controller look like an existing one :) It's very simple,
but I should be able to make it look like spi-oc-tiny.c quite easily.

Now as for chip-selects... I could also add some concept of GPIOs,
write a simple MMIO GPIO controller etc... or I could for now make my
life easier and send a patch adding an extra register to control chip
select to spi-oc-tiny.c keyd off a device-tree property (or the
compatible property) :-)

Any objection to the "easy/fast" way :-) ?

Cheers,
Ben.