Pull-down means backlight is present, pull-up means backlight
is absent.
After detection, we still apply internal pull-down on the GPIO,
to make sure old boards with both pull-up and pull-down stuffed
do not always keep backlight on.
BRANCH=none
BUG=b:67722756
TEST=On reworked board with pull-down on backlight pin,
backlight works, and "Backlight present" shown in console.
TEST=On old board with both pull-up and pull-down, backlight is
off by default, and "Backlight not present" shown in console.
Change-Id: I6988c6ef8f4d155a08967db34f72d7ea4c835306
Signed-off-by: Nicolas Boichat <drinkcat@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/538458
Reviewed-by: Vincent Palatin <vpalatin@chromium.org>
This is part one of a series to merge the keyboard scan interface to
be common across all platforms.
This change just moves and renames files and APIs and removes some
read code, and sets up protocol-specific CONFIG options. It makes the
next CL which actually merges keyboard scanning easier to parse.
BUG=chrome-os-partner:18360
BRANCH=none
TEST=compile all boards; test keyboard on spring and link
Change-Id: I815a40aae4e5d5f333b8501aff9656080533d913
Signed-off-by: Randall Spangler <rspangler@chromium.org>
Reviewed-on: https://gerrit.chromium.org/gerrit/46549
Reviewed-by: Bill Richardson <wfrichar@chromium.org>
