Re: [PATCH v2 0/3] increase TSCADC clock to 24MHz and fix ti,charge-delay to represent in nS

From: Mugunthan V N
Date: Thu Nov 24 2016 - 23:57:38 EST

Hi Dmitry Torokhov,

On Thursday 10 November 2016 10:05 PM, Mugunthan V N wrote:
> This patch series enables ADC to be clocked at 24MHz as the
> TI AM335x ADC driver has already adopted to use DMA to transfer
> ADC samples. Now ADC can generated upto 800K Samples per second
> with the patch [1] on AM335x BBB and AM437x GP EVM.
> when ADC ref clock is set at 24MHz, I am seeing some issue with
> touch screen pointer as the pointer jumps to random locations
> with free draw application. The issue is due to increase in ADC
> clock and charge delay for the touchscreen ADC line duration
> reduced.
> So the notation of ti,charge-delay in terms of ADC clock is
> wrong, it has to be represented in time and driver has to convert
> the charge delay time to ADC clocks based on what ADC clock
> frequency is set.
> Measured the performance with the iio_generic_buffer with the
> patch [2] applied
> Verified the touch screen on AM335x GP EVM and AM335x BBB LCD7
> cape with [3] dts for display and touch screen to work.

Since there are acks from DT and MFD maintainers, can you pull the patch
series if you do not have any more comments.

Mugunthan V N