[PATCH v6 2/6] input: touchscreen: ti_am335x_tsc: Remove udelay in interrupt handler

Dmitry Torokhov dmitry.torokhov at gmail.com
Tue Feb 3 11:49:56 PST 2015


On Fri, Jan 30, 2015 at 10:56:28AM +0530, Vignesh R wrote:
> 
> 
> On Wednesday 07 January 2015 11:19 AM, Vignesh R wrote:
> > From: Brad Griffis <bgriffis at ti.com>
> > 
> > TSC interrupt handler had udelay to avoid reporting of false pen-up
> > interrupt to user space. This patch implements workaround suggesting in
> > Advisory 1.0.31 of silicon errata for am335x, thus eliminating udelay
> > and touchscreen lag. This also improves performance of touchscreen and
> > eliminates sudden jump of cursor at touch release.
> > 
> > IDLECONFIG and CHARGECONFIG registers are to be configured
> > with same values in order to eliminate false pen-up events. This
> > workaround may result in false pen-down to be detected, hence considerable
> > charge step delay needs to be added. The charge delay is set to 0xB000
> > (in terms of ADC clock cycles) by default.
> > 
> > TSC steps are disabled at the end of every sampling cycle and EOS bit is
> > set. Once the EOS bit is set, the TSC steps need to be re-enabled to begin
> > next sampling cycle.
> > 
> > Signed-off-by: Brad Griffis <bgriffis at ti.com>
> > [vigneshr at ti.com: Ported the patch from v3.12 to v3.19rc1]
> > 
> > Signed-off-by: Vignesh R <vigneshr at ti.com>
> > ---
> 
> Ping... Can somebody pick this patch series if there are no more comments??

Yes, I picked up everything but patch #3 as I assume Lee will merge it
through MFD tree.

Thanks.

-- 
Dmitry



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