Randall Spangler f28f2b2e51 Use open drain reset signals, and clean up signals to 5VALW-powered devices ...

Open drain cleanup minimizes leakage and signal glitching on shared
reset/signal lines, and is tidier than explicitly switching the
signals between inputs/outputs.

Touchscreen and lightbar are powered by +5VALW so their signals need
to be dropped when +5VALW is off to avoid leakage, and so they see a
clean reset signal when they're powered up.

Moved +5VALW power-on to S5-S3 transition, to minimize power draw in
S5.  This also ensures that 5VALW-powered devices get reset when the
device bounces through S5.  (No effect on proto1, where 5VALW is not
under EC control.)

Signed-off-by: Randall Spangler <rspangler@chromium.org>

BUG=chrome-os-partner:9172
TEST=boot and shutdown system; still works.

Change-Id: Ia4bf0703292a189c324ce283d1e79a33776ee40f

2012-05-10 15:17:01 -07:00

..

lm4

Use open drain reset signals, and clean up signals to 5VALW-powered devices

2012-05-10 15:17:01 -07:00

stm32

daisy: Remove start-up message from keyboard scan

2012-05-10 12:37:42 -07:00