Re: [PATCH 1/2] dt-bindings: spi: Add Spreadtrum SPI controller documentation

From: Baolin Wang
Date: Wed Aug 08 2018 - 23:03:25 EST


Hi Trent,

On 9 August 2018 at 02:57, Trent Piepho <tpiepho@xxxxxxxxxx> wrote:
> On Wed, 2018-08-08 at 11:54 +0100, Mark Brown wrote:
>> On Wed, Aug 08, 2018 at 06:35:28PM +0800, Baolin Wang wrote:
>> > On 8 August 2018 at 17:50, Mark Brown <broonie@xxxxxxxxxx> wrote:
>> > > Right, I don't think we added this yet (if we did I can't see
>> > > it). I'd
>> > > add a new field to spi_transfer for this, then other controllers
>> > > with
>> > > the same support can implement it as well and drivers can start
>> > > using
>> > > it too.
>> > OK. So I will name the new filed as 'word_delay', is it OK for you?
>>
>> Sounds good, yes.
>
> Should it be in Âs like the existing iter-transfer delay? I think
> perhaps units of cycles of the SPI clock make more sense?

Since some SPI controllers just want some interval values (neither Âs
unit nor cycles unit ) set into hardware, and the hardware will
convert to the correct delay time automatically. So I did not force
'word_delay' unit as Âs or cycle, and just let the slave devices
decide the unit which depends on the SPI hardware requirement.

--
Baolin Wang
Best Regards