summaryrefslogtreecommitdiff
path: root/power
diff options
context:
space:
mode:
authorRandall Spangler <rspangler@chromium.org>2014-03-06 14:26:42 -0800
committerchrome-internal-fetch <chrome-internal-fetch@google.com>2014-03-07 02:21:03 +0000
commit9de183a5d66aa7c07287f6b7793f6e266b6b376b (patch)
tree0990ddc573b8471848aa4edb9be67ed594594614 /power
parentfcdb93668a32f3d2d311f113484eed1df5c613de (diff)
downloadchrome-ec-9de183a5d66aa7c07287f6b7793f6e266b6b376b.tar.gz
rambi: Add 7 ms delay before turning off PP3300_DX at shutdown
This works around an issue where LCDVCC falls too slowly. The impact is to slow shutdown by 7 ms, which isn't noticeable to the user. BUG=chrome-os-partner:26561 BRANCH=rambi TEST=shut down rambi; still shuts down, and ~7 ms more time is spent in S0->S3 state. before: [429.933010 power state 3 = S0, in 0x043f] [429.933240 power state 7 = S0->S3, in 0x043f] [429.933614 power state 2 = S3, in 0x042b] [429.934013 power state 8 = S3->S5, in 0x0428] after: [20.355975 power state 3 = S0, in 0x003f] [20.356194 power state 7 = S0->S3, in 0x003f] [20.363957 power state 2 = S3, in 0x002c] [20.364179 power state 8 = S3->S5, in 0x002c] [20.364877 power state 1 = S5, in 0x0008] Change-Id: Ie843bdcf740f3dbc1b866a0356cea2a8b42d4194 Signed-off-by: Randall Spangler <rspangler@chromium.org> Reviewed-on: https://chromium-review.googlesource.com/189092 Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Diffstat (limited to 'power')
-rw-r--r--power/baytrail.c1
1 files changed, 1 insertions, 0 deletions
diff --git a/power/baytrail.c b/power/baytrail.c
index b44e1b8e27..5349045520 100644
--- a/power/baytrail.c
+++ b/power/baytrail.c
@@ -314,6 +314,7 @@ enum power_state power_handle_state(enum power_state state)
gpio_set_level(GPIO_CPU_PROCHOT, 0);
/* Turn off power rails */
+ msleep(7); /* Small delay; see crosbug.com/p/26561 */
gpio_set_level(GPIO_PP3300_DX_EN, 0);
#ifdef CONFIG_USB_PORT_POWER_IN_S3