From 55231d8299d3dccde8588ed2e86c2bc0ef2e12ce Mon Sep 17 00:00:00 2001 From: Henry Chen Date: Mon, 4 Jan 2016 20:02:52 +0800 Subject: [PATCH 027/102] soc: mediatek: PMIC wrap: Clear the vldclr if state machine stay on FSM_VLDCLR state. Sometimes PMIC is too busy to send data in time to cause pmic wrap timeout, because pmic wrap is waiting for FSM_VLDCLR after finishing WACS2_CMD. It just return error when issue happened, so the state machine will stay on FSM_VLDCLR state when data send back later by PMIC and timeout again in next time because pmic wrap waiting for FSM_IDLE state at the beginning of the read/write function. Clear the vldclr when timeout if state machine stay on FSM_VLDCLR. Signed-off-by: Henry Chen Tested-by: Ricky Liang Signed-off-by: Matthias Brugger --- drivers/soc/mediatek/mtk-pmic-wrap.c | 22 ++++++++++++++++++++-- 1 file changed, 20 insertions(+), 2 deletions(-) --- a/drivers/soc/mediatek/mtk-pmic-wrap.c +++ b/drivers/soc/mediatek/mtk-pmic-wrap.c @@ -412,6 +412,20 @@ static bool pwrap_is_fsm_vldclr(struct p return PWRAP_GET_WACS_FSM(val) == PWRAP_WACS_FSM_WFVLDCLR; } +/* + * Timeout issue sometimes caused by the last read command + * failed because pmic wrap could not got the FSM_VLDCLR + * in time after finishing WACS2_CMD. It made state machine + * still on FSM_VLDCLR and timeout next time. + * Check the status of FSM and clear the vldclr to recovery the + * error. + */ +static inline void pwrap_leave_fsm_vldclr(struct pmic_wrapper *wrp) +{ + if (pwrap_is_fsm_vldclr(wrp)) + pwrap_writel(wrp, 1, PWRAP_WACS2_VLDCLR); +} + static bool pwrap_is_sync_idle(struct pmic_wrapper *wrp) { return pwrap_readl(wrp, PWRAP_WACS2_RDATA) & PWRAP_STATE_SYNC_IDLE0; @@ -445,8 +459,10 @@ static int pwrap_write(struct pmic_wrapp int ret; ret = pwrap_wait_for_state(wrp, pwrap_is_fsm_idle); - if (ret) + if (ret) { + pwrap_leave_fsm_vldclr(wrp); return ret; + } pwrap_writel(wrp, (1 << 31) | ((adr >> 1) << 16) | wdata, PWRAP_WACS2_CMD); @@ -459,8 +475,10 @@ static int pwrap_read(struct pmic_wrappe int ret; ret = pwrap_wait_for_state(wrp, pwrap_is_fsm_idle); - if (ret) + if (ret) { + pwrap_leave_fsm_vldclr(wrp); return ret; + } pwrap_writel(wrp, (adr >> 1) << 16, PWRAP_WACS2_CMD);