Re: spi-gpio too fast for some devices

[Christian Mauderer <oss@xxxxxxxxxxxxx>]

On 02/07/2019 15:00, Mark Brown wrote:
> On Mon, Jul 01, 2019 at 08:33:27PM +0200, Christian Mauderer wrote:
>> On 01/07/2019 19:26, Mark Brown wrote:
> 
>>> I was actually thinking of a DT property but yes that too, probably
>>> would be useful for people trying to figure out the right number.
> 
>> My experience with the device tree from last time (a LED driver) was
>> that implementation specific properties are not that popular. A property
> 
> No, they're absolutely fine when they have a use case.
> 
>> that tells one special driver from which speed on it should just ignore
>> the speed and try it's best to do max speed seems quite implementation
>> specific. Maybe except if I try to introduce a max-speed property to the
>> SPI slaves that can be used instead of the speed.
> 
> You can already set the maximum speed - this is about tuning a
> very system specific point to switch implementations.
> 

Sorry, bad choice of words. I meant that I could try to introduce a
value for the maximum speed setting to just use the best that is
possible. Something like

    spi-max-frequency = "AS_FAST_AS_POSSIBLE"

But I think I'll just start with the implementation and discuss that as
soon as I have a working prototype.