From: Stephan Gerhold stephan@gerhold.net
[ 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 cw00.choi@samsung.com Signed-off-by: Stephan Gerhold stephan@gerhold.net Signed-off-by: Chanwoo Choi cw00.choi@samsung.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/extcon/extcon-sm5502.c | 4 ++++ drivers/extcon/extcon-sm5502.h | 2 ++ 2 files changed, 6 insertions(+)
diff --git a/drivers/extcon/extcon-sm5502.c b/drivers/extcon/extcon-sm5502.c index 7aac3cc7efd7..f63f9961ac12 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 <<SM5502_REG_MANUAL_SW1_DP_SHIFT) \ | (DM_DP_CON_SWITCH_UART <<SM5502_REG_MANUAL_SW1_DM_SHIFT))
+#define SM5502_REG_RESET_MASK (0x1) + /* SM5502 Interrupts */ enum sm5502_irq { /* INT1 */