From 3d384486190c37e8162543fed53da0a7040712d9 Mon Sep 17 00:00:00 2001 From: Naresh G Solanki Date: Mon, 19 Jun 2017 15:07:44 +0530 Subject: [PATCH] mb/google/soraka: Do not reset PMIC during sleep 1. Due to reset signal, PMIC loses its internal register state. This causes PMIC to be in improper state after sleep. 2. The intent of reset signal is to reset internal state of PMIC (which happens once during power on), hence avoid asserting reset signal when not needed. 3. As per PMIC (TPS68470) datasheet, device can be kept in SLEEP mode when not in use to save max possible power. To fix the same, do not reset PMIC while entering sleep. By keeping PMIC in SLEEP mode, Power consumption is < 1uW (Typ) upto 3.63uW (Max). Refs: TPS68470 datasheet. Measured value: 0.66uW TEST= Build the firmware for Soraka & boot to OS. Do S3 resume & check whether PMIC internal registers state are preserved. Change-Id: I93ce4d76b0376b64ae6d1067aca0fd7467af3582 Signed-off-by: Naresh G Solanki Reviewed-on: https://review.coreboot.org/20264 Tested-by: build bot (Jenkins) Reviewed-by: Paul Menzel Reviewed-by: Furquan Shaikh --- src/mainboard/google/poppy/smihandler.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/src/mainboard/google/poppy/smihandler.c b/src/mainboard/google/poppy/smihandler.c index 30b009dd6f..1a86d0f773 100644 --- a/src/mainboard/google/poppy/smihandler.c +++ b/src/mainboard/google/poppy/smihandler.c @@ -29,8 +29,7 @@ void mainboard_smi_espi_handler(void) static void mainboard_gpio_smi_sleep(void) { - /* Hold camera device in reset and then power it down. */ - gpio_set(EN_CAM_PMIC_RST_L, 0); + /* Power down camera PMIC */ gpio_set(EN_PP3300_DX_CAM, 0); }