WSL2-Linux-Kernel/arch/avr32/boards
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
..
atngw100 avr32: Add support for Mediama RMTx add-on board for ATNGW100 2009-06-08 12:55:35 +02:00
atstk1000 avr32: add RTS/CTS/CLK pin selection for the USARTs 2009-04-01 16:13:45 +02:00
favr-32 favr32: improve touchscreen response 2009-07-27 13:16:45 +02:00
hammerhead dma-mapping: replace all DMA_32BIT_MASK macro with DMA_BIT_MASK(32) 2009-04-07 08:31:11 -07:00
merisc avr32: Solves problem with inverted MCI detect pin on Merisc board 2009-04-08 20:48:02 +02:00
mimc200 Fix MIMC200 board LCD init 2009-06-03 15:10:04 +02:00