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

Jürgen Beisert jbe at pengutronix.de
Thu Sep 19 08:49:37 EDT 2013


Hi Jonathan,

On Monday 16 September 2013 17:30:32 Jonathan Cameron wrote:
> >On Sunday 15 September 2013 12:56:25 Jonathan Cameron wrote:
> >> On 09/11/13 09:18, Juergen Beisert wrote:
> >> > 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 <jbe at pengutronix.de>
> >> > CC: linux-arm-kernel at lists.infradead.org
> >> > CC: devel at driverdev.osuosl.org
> >> > CC: Marek Vasut <marex at denx.de>
> >> > CC: Fabio Estevam <fabio.estevam at freescale.com>
> >> > CC: Jonathan Cameron <jic23 at cam.ac.uk>
> >>
> >> 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?
>
> That would be great and is definitely the preferred method.

Cannot continue to convert the driver into an MFD device. The project does not 
give me the time to do so.

Regards,
Juergen

-- 
Pengutronix e.K.                              | Juergen Beisert             |
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