spi: omap2-mcspi: Add comments for RX only DMA buffer workaround
authorFranklin S Cooper Jr <fcooper@ti.com>
Mon, 27 Jun 2016 14:54:08 +0000 (09:54 -0500)
committerMark Brown <broonie@kernel.org>
Tue, 5 Jul 2016 14:48:25 +0000 (16:48 +0200)
commit4bd00413cde851d84b297c1b0dae15109025e84b
tree9b4b411dd05c7dfa70dad52b2fb8147fca891e5a
parent1a695a905c18548062509178b98bc91e67510864
spi: omap2-mcspi: Add comments for RX only DMA buffer workaround

OMAP35x and OMAP37x mentions in the McSPI End-of-Transfer Sequences section
that if the McSPI is configured as a Master and only DMA RX is being
performed then the DMA transfer size needs to be reduced by 1 or 2.

This was originally implemented by:
commit 57c5c28dbc83 ("spi: omap2_mcspi rxdma bugfix")

This patch adds comments to clarify what is going on in the code since its
not obvious what problem its addressing.

Signed-off-by: Franklin S Cooper Jr <fcooper@ti.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
drivers/spi/spi-omap2-mcspi.c