linux/arch
Ben Nizette 92c548cd35 favr32: improve touchscreen response
The ezLCD+101 board (to which an favr-32 is fitted) has a long,
unshielded, nasty lead between the touch panel and the ads7843 touch
controller.  In order to get satisfactory response then, we need to
employ every noise-reduction trick in the driver's arsenal.  After
extensive fiddling I've found some good settings:

1) We keep vref on all the time to dramatically reduce settling times
(at the cost of a tiny increase in power consumption).

2) Despite 1 the settling time is still non-zero.  500uS is plenty of
time for the signals to settle

3) Despite 1 and 2 there's still a little bit of noise around.  By
setting a pen recheck delay we make the panel feel less touchy and
twitchy.

Someone with more time and patience myself might be able to tune this
numbers further but these settings are now perfectly acceptable for
normal use.

Tested on ezLCD+101 though should only improve response on other ezLCD+/
favr-32 boards too.

Signed-off-by: Ben Nizette <bn@niasdigital.com>
Signed-off-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
2009-07-27 13:16:45 +02:00
..
alpha headers: smp_lock.h redux 2009-07-12 12:22:34 -07:00
arm Merge master.kernel.org:/home/rmk/linux-2.6-arm 2009-07-18 11:59:33 -07:00
avr32 favr32: improve touchscreen response 2009-07-27 13:16:45 +02:00
blackfin blackfin: fix wrong CTS inversion 2009-07-20 16:38:44 -07:00
cris headers: smp_lock.h redux 2009-07-12 12:22:34 -07:00
frv sched: INIT_PREEMPT_COUNT 2009-07-10 14:24:05 -07:00
h8300 sched: INIT_PREEMPT_COUNT 2009-07-10 14:24:05 -07:00
ia64 Revert "Neither asm/types.h nor linux/types.h is required for arch/ia64/include/asm/fpu.h" 2009-07-17 06:35:05 -07:00
m32r headers: smp_lock.h redux 2009-07-12 12:22:34 -07:00
m68k sched: INIT_PREEMPT_COUNT 2009-07-10 14:24:05 -07:00
m68knommu Remove multiple KERN_ prefixes from printk formats 2009-07-08 10:30:03 -07:00
microblaze headers: smp_lock.h redux 2009-07-12 12:22:34 -07:00
mips headers: smp_lock.h redux 2009-07-12 12:22:34 -07:00
mn10300 vmlinux.lds.h: restructure BSS linker script macros 2009-07-18 00:02:45 +02:00
parisc sched: INIT_PREEMPT_COUNT 2009-07-10 14:24:05 -07:00
powerpc powerpc: Fix another bug in move of altivec code to vector.S 2009-07-15 17:41:46 +10:00
s390 headers: smp_lock.h redux 2009-07-12 12:22:34 -07:00
sh headers: smp_lock.h redux 2009-07-12 12:22:34 -07:00
sparc Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6 2009-07-13 10:24:08 -07:00
um sched: INIT_PREEMPT_COUNT 2009-07-10 14:24:05 -07:00
x86 Merge branch 'perf-counters-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/peterz/linux-2.6-perf 2009-07-22 11:41:56 -07:00
xtensa sched: INIT_PREEMPT_COUNT 2009-07-10 14:24:05 -07:00
.gitignore
Kconfig gcov: add gcov profiling infrastructure 2009-06-18 13:03:57 -07:00