[PATCH RFT 4/5] iio: mxs-lradc: disable only mapped channels in mxs_lradc_hw_stop

[Stefan Wahren]

Hi Jonathan,

Am 17.04.2016 um 12:47 schrieb Jonathan Cameron:
> On 14/04/16 16:48, Stefan Wahren wrote:
>> Disabling of the touchscreen IRQs is already done in
>> mxs_lradc_disable_ts. There is no need to disable them in
>> mxs_lradc_hw_stop again.
> We could do with a little more documentation in the driver on
> which bits in this register are doing what.
>
> The disable_ts deals with bits 22-24... 
> The only other bit I think is ever used by the driver currently is
> 16 (channel 0).  
>
> So whilst this change probably works, I'm not sure of the logic behind it.
> As far as I can tell your new clear is fine but in reality you could
> just clear (0x3f << 16) and get the same result (which would be clearer
> to my mind).
>
> The key think here is that we don't support the higher bits on i.mx28
> yet... Which are for button detection and threshold detection.
>
> Have I understood this correctly?

Yes, you are. I've have looked to long in the reference manual instead
of the code.
I've missed the point that virtual channel 6 and 7 are used in case of a
connected touchscreen.

I should use the member buffer_vchans for masking the enable IRQs.

Regards
Stefan

>
> Jonathan
>  So we only need to care of the