From e9555e31fe7a853f18bd6ecea74b575e9262ce2c Mon Sep 17 00:00:00 2001 From: Stephan Gerhold Date: Thu, 10 Oct 2019 17:47:20 +0200 Subject: extcon: sm5502: Reset registers during initialization [ Upstream commit 6942635032cfd3e003e980d2dfa4e6323a3ce145 ] On some devices (e.g. Samsung Galaxy A5 (2015)), the bootloader seems to keep interrupts enabled for SM5502 when booting Linux. Changing the cable state (i.e. plugging in a cable) - until the driver is loaded - will therefore produce an interrupt that is never read. In this situation, the cable state will be stuck forever on the initial state because SM5502 stops sending interrupts. This can be avoided by clearing those pending interrupts after the driver has been loaded. One way to do this is to reset all registers to default state by writing to SM5502_REG_RESET. This ensures that we start from a clean state, with all interrupts disabled. Suggested-by: Chanwoo Choi Signed-off-by: Stephan Gerhold Signed-off-by: Chanwoo Choi Signed-off-by: Sasha Levin --- drivers/extcon/extcon-sm5502.c | 4 ++++ drivers/extcon/extcon-sm5502.h | 2 ++ 2 files changed, 6 insertions(+) (limited to 'drivers/extcon') diff --git a/drivers/extcon/extcon-sm5502.c b/drivers/extcon/extcon-sm5502.c index 106ef0297b53..1a1ee3db3455 100644 --- a/drivers/extcon/extcon-sm5502.c +++ b/drivers/extcon/extcon-sm5502.c @@ -69,6 +69,10 @@ struct sm5502_muic_info { /* Default value of SM5502 register to bring up MUIC device. */ static struct reg_data sm5502_reg_data[] = { { + .reg = SM5502_REG_RESET, + .val = SM5502_REG_RESET_MASK, + .invert = true, + }, { .reg = SM5502_REG_CONTROL, .val = SM5502_REG_CONTROL_MASK_INT_MASK, .invert = false, diff --git a/drivers/extcon/extcon-sm5502.h b/drivers/extcon/extcon-sm5502.h index 974b53222f56..12f8b01e5753 100644 --- a/drivers/extcon/extcon-sm5502.h +++ b/drivers/extcon/extcon-sm5502.h @@ -241,6 +241,8 @@ enum sm5502_reg { #define DM_DP_SWITCH_UART ((DM_DP_CON_SWITCH_UART <