diff options
| author | Nicolas Boichat <drinkcat@chromium.org> | 2017-08-23 09:06:55 +0800 |
|---|---|---|
| committer | chrome-bot <chrome-bot@chromium.org> | 2017-08-23 00:04:09 -0700 |
| commit | 9ea128966ba11e4a756d1a83fd0fe2d247d0312c (patch) | |
| tree | 8532161f0e9d1501e60fc4f79e82f760d81ec3b6 /board/hammer | |
| parent | 9c1cf6def5b04948f1c4142ac766a969ee9d5fa0 (diff) | |
| download | chrome-ec-9ea128966ba11e4a756d1a83fd0fe2d247d0312c.tar.gz | |
hammer: Pull down PWM output pin
Some staff boards were accidentally built with both pull-up and
pull-down stuffed, leaving the backlight output always on when
the EC is not driving the pin.
This "fixes" the issue by adding an internal pull-down on the pin,
so that the pin is pulled low whenever the PWM is disabled.
BRANCH=none
BUG=b:64845198
TEST=staff EC console:
pwm 0 -1 => backlight is off
pwm 0 0 => backlight still off
pwm 0 100 => backlight full intensity
TEST=Power consumption with PWM disabled (pwm 0 -1) and always 0
(pwm 0 0) are comparable.
Change-Id: I32549bfc037a6506470408f8e98cae5ae56006e2
Signed-off-by: Nicolas Boichat <drinkcat@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/627345
Reviewed-by: Furquan Shaikh <furquan@chromium.org>
Diffstat (limited to 'board/hammer')
| -rw-r--r-- | board/hammer/gpio.inc | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/board/hammer/gpio.inc b/board/hammer/gpio.inc index 17c3bc5cff..b9eb46c09b 100644 --- a/board/hammer/gpio.inc +++ b/board/hammer/gpio.inc @@ -58,4 +58,4 @@ ALTERNATE(PIN_MASK(A, 0x0600), 1, MODULE_UART, GPIO_PULL_UP) /* USART1: PA09/PA1 ALTERNATE(PIN_MASK(B, 0x00c0), 1, MODULE_I2C, 0) /* I2C MASTER:PB6/7 GPIO_ODR_HIGH */ -ALTERNATE(PIN_MASK(B, 0x0200), 2, MODULE_PWM, GPIO_DEFAULT) /* PWM: PB9 */ +ALTERNATE(PIN_MASK(B, 0x0200), 2, MODULE_PWM, GPIO_PULL_DOWN) /* PWM: PB9 */ |