[PATCH 3/5] spi: sunxi: expose maximum transfer size limit

Maxime Ripard maxime.ripard at free-electrons.com
Wed Jun 1 11:14:39 PDT 2016


On Mon, May 30, 2016 at 10:57:10AM +0200, Michal Suchanek wrote:
> Hello,
> 
> On 30 May 2016 at 10:37, Maxime Ripard <maxime.ripard at free-electrons.com> wrote:
> > On Thu, May 26, 2016 at 07:25:24PM -0000, Michal Suchanek wrote:
> >> The sun4i spi hardware can trasfer at most 63 bytes of data without DMA
> >> support so report the limitation. Same on sun6i.
> >
> > Is it? Is there timeouts on the A31 and later SoCs?
> >
> 
> I have no sun6i hardware to test with.
> 
> This is an advisory limit you can query and it better be smaller
> rather than unreliable. The hard limit in the driver is still
> SUN6I_FIFO_DEPTH (which is 128 bytes on sun6i).
> 
> You can test his without any actual SPI device. Unused pins you can
> multiplex as SPI suffice.

Ok, for the time being:

Acked-by: Maxime Ripard <maxime.ripard at free-electrons.com>

Thanks!
Maxime

-- 
Maxime Ripard, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com
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