[PATCH 1/2 V4] iio: mxs: Implement support for touchscreen

[marex@denx.de (Marek Vasut)]

Dear Jonathan Cameron,

> On 01/13/2013 03:09 AM, Dmitry Torokhov wrote:
> > On Sat, Jan 12, 2013 at 12:35:07AM +0100, Marek Vasut wrote:
> >> This patch implements support for sampling of a touchscreen into
> >> the MXS LRADC driver. The LRADC block allows configuring some of
> >> it's channels into special mode where they either output the drive
> >> voltage or sample it, allowing it to operate a 4-wire or 5-wire
> >> resistive touchscreen.
> >> 
> >> In case the touchscreen mode is enabled, the LRADC slot #7 is
> >> reserved for touchscreen only, therefore it is not possible to
> >> sample 8 LRADC channels at time, but only 7 channels.
> >> 
> >> The touchscreen controller is configured such that the PENDOWN event
> >> disables touchscreen interrupts and triggers execution of worker
> >> thread, which then polls the touchscreen controller for X, Y and
> >> Pressure values. This reduces the overhead of interrupt-driven
> >> operation. Upon the PENUP event, the worker thread re-enables the
> >> PENDOWN detection interrupt and exits.
> >> 
> >> Signed-off-by: Marek Vasut <marex@denx.de>
> >> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
> > 
> > Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
> 
> I've added this to the togreg branch of
> git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio.git
> 
> Note it did not directly apply as I'm guessing you have a slightly
> out of date tree.

Ah yes, it was still based off of stable 3.7 .

> Please could you check I didn't mess up the
> fixing up of the patch. There was a fair bit of fuzz and the devinit
> devexit stuff shouldn't have been in your patch in the first place.

Checked just now, looks OK to me, thanks!

> Shawn, do you want to take the board device tree patch or shall
> I take that one as well?
> 
> Jonathan