Re: [PATCH] i2c: mxs: fix broken timing calculation

[Marek Vasut <marex-ynQEQJNshbs@public.gmane.org>]

Dear Lothar Waßmann,

> Hi,
> 
> Marek Vasut writes:
> > > > btw offtopic, I will at least try to fix the PIO in the meantime.
> > > 
> > > Did you succeed at this? Because this is the real problem for the
> > > DS1339 failing on our board. With DMA only transfers it works, but
> > > other chips (TSC2007, PCA9554, SGTL5000) fail.
> > 
> > Is that correct to assume that even DMA fails? So far I got to a patch
> > [1], which is almost an RFC, but please give it a go. I suspect I didn't
> > CC you, I will CC you on V2.
> 
> I applied that patch and all the above mentioned devices seem to work
> with it.
> And with my patch the timing is also correct.

First, please accept my appology for the delay. I finally measured the bus. 
Without this patch, I see 107khz at 100kHz setting and 410kHz at 400kHz setting. 
With this patch I see 93kHz and 307kHz respectively.

I suspect the result really is board-dependent. Can you measure MX28EVK so we 
know what the result is there please? I don't have one here. 

Best regards,
Marek Vasut