Hung-Te Lin has submitted this change. ( https://review.coreboot.org/c/coreboot/+/47443 )
Change subject: mb/google/kukui: Fix LCD sequence T3 fail issue ......................................................................
mb/google/kukui: Fix LCD sequence T3 fail issue
The T3 that PPVARN_LCD low to LCM_RST_1V8 high is 0.1269ms and it does not meet the LCD specification that the T3 must be larger than 5ms. Because there is a delay between PPVARN_LCD_EN and PPVARN_LCD. An extra 9ms delay should be added on LCM_RST_1V8 in order to meet the specification "ProductSpec_NV105WUM-A51_ V4.3_P2(TLCM).pdf".
BUG=b:172201138 BRANCH=kukui TEST=The LCD sequence T3 is larger than 5ms when power on.
Signed-off-by: Tao Xia xiatao5@huaqin.corp-partner.google.com Change-Id: Iaf7ae494e30c4c207103d949287b335288688c54 Reviewed-on: https://review.coreboot.org/c/coreboot/+/47443 Tested-by: build bot (Jenkins) no-reply@coreboot.org Reviewed-by: Hung-Te Lin hungte@chromium.org Reviewed-by: Yu-Ping Wu yupingso@google.com --- M src/mainboard/google/kukui/mainboard.c 1 file changed, 1 insertion(+), 1 deletion(-)
Approvals: build bot (Jenkins): Verified Hung-Te Lin: Looks good to me, approved Yu-Ping Wu: Looks good to me, but someone else must approve
diff --git a/src/mainboard/google/kukui/mainboard.c b/src/mainboard/google/kukui/mainboard.c index 268b7ca..cbcb5da 100644 --- a/src/mainboard/google/kukui/mainboard.c +++ b/src/mainboard/google/kukui/mainboard.c @@ -91,7 +91,7 @@ gpio_output(GPIO_PPVARN_LCD_EN, 1); gpio_output(GPIO_PP1800_LCM_EN, 1); gpio_output(GPIO_PP3300_LCM_EN, 1); - mdelay(6); + mdelay(15); gpio_output(GPIO_LCM_RST_1V8, 1); mdelay(6); }