Re: [PATCH 5/6] Staging/iio/adc/touchscreen/MXS: add interrupt driven touch detection

Hi Jonathan,

On Sunday 15 September 2013 12:56:25 Jonathan Cameron wrote:

On 09/11/13 09:18, Juergen Beisert wrote:

quoted

For battery driven systems it is a very bad idea to collect the
touchscreen data within a kernel busy loop.

This change uses the features of the hardware to delay and accumulate
samples in hardware to avoid a high interrupt and CPU load.

Note: this is only tested on an i.MX23 SoC yet.

Signed-off-by: Juergen Beisert <redacted>
CC: linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org
CC: devel-gWbeCf7V1WCQmaza687I9mD2FQJk+8+b@public.gmane.org
CC: Marek Vasut <redacted>
CC: Fabio Estevam <redacted>
CC: Jonathan Cameron <jic23-KWPb1pKIrIJaa/9Udqfwiw@public.gmane.org>

While this driver is placed in IIO within staging at the moment, these
changes are definitely input related.  Hence I have cc'd Dmitry and the
input list.

I am personaly a little uncomfortable that we have such a complex bit of
input code sat within an IIO driver but such is life.

Maybe an MFD for this ADC unit would be a better way to go? Currently I have a 
different problem with this driver, because the ADC unit monitors the battery 
as well. And the charging driver from the power subsystem needs these values 
to charge the battery in a correct manner.

[...]

Regards,
Juergen

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