nanopi/allwinner i2c not working.

[Daniel Braniss]

> On 7 Oct 2020, at 11:33, Andriy Gapon <avg at FreeBSD.org> wrote:
> 
> On 07/10/2020 10:54, Daniel Braniss wrote:
>> with D26049:
>> i2s -s works with and without debug
>> 
>> my test runs ok with debug on, but failed with debug off.
>> timing issue?
> 
> That's interesting.
> I also have an H3-based system and did not see anything like that with any of
> I2C devices that I have.
> The latest driver is completely interrupt driven and there are no fixed delays.
> The controller datasheet does not seem to mandate any delays as well.
> Perhaps the problem is on the device's side?
> Also, it could be that the older driver (in 12.1) was slower, so more forgiving
> of any wiring / connector problems.
> 
> Not sure how to proceed when debug mode works fine and non-debug fails.
> Perhaps DTrace would be less overhead than the debug printf-s.
> 
> Ah, another thought, with debugging enabled, could you please do a bus reset and
> see what mode and clock param get printed?

iichb0: twsi_calc_baud_rate: Bus clock is at 24000000
iichb0: twsi_reset: Using clock param=59

> 
> -- 
> Andriy Gapon