Hi Matthias,

On Wed, 2015-12-30 at 19:02 +0100, Matthias Brugger wrote:

On 22/12/15 08:51, Henry Chen wrote:

quoted

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 begining of the
read/write function.

Clear the vldclr when timeout if state machine is stay on FSM_VLDCLR.

Signed-off-by: Henry Chen <redacted>
---
  drivers/soc/mediatek/mtk-pmic-wrap.c | 16 ++++++++++++++--
  1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/drivers/soc/mediatek/mtk-pmic-wrap.c b/drivers/soc/mediatek/mtk-pmic-wrap.c
index 105597a..ccd5337 100644
--- a/drivers/soc/mediatek/mtk-pmic-wrap.c
+++ b/drivers/soc/mediatek/mtk-pmic-wrap.c

@@ -443,10 +443,16 @@ static int pwrap_wait_for_state(struct pmic_wrapper *wrp,
  static int pwrap_write(struct pmic_wrapper *wrp, u32 adr, u32 wdata)
  {
  	int ret;
+	u32 val;

  	ret = pwrap_wait_for_state(wrp, pwrap_is_fsm_idle);
-	if (ret)
+	if (ret) {
+		/* Clear vldclr bit if state is on the WACS_FSM_WFVLDCLR */
+		val = pwrap_readl(wrp, PWRAP_WACS2_RDATA);
+		if (PWRAP_GET_WACS_FSM(val) == PWRAP_WACS_FSM_WFVLDCLR)
+			pwrap_writel(wrp, 1, PWRAP_WACS2_VLDCLR);
  		return ret;
+	}

I would prefer to have this encapsulated in a (inline) function. Maybe 
with better description then just the one line comment.

Thanks,
Matthias

Ok, I will make the description more clear, do you means write the
function like below and used it on pwrap_write/pwrap_read.

static inline void pwrap_leave_fsm_vldclr(struct pmic_wrapper *wrp)
{
	if (pwrap_is_fsm_vldclr(wrp))
		pwrap_writel(wrp, 1, PWRAP_WACS2_VLDCLR);
}


Thanks,
Henry

quoted

  	pwrap_writel(wrp, (1 << 31) | ((adr >> 1) << 16) | wdata,
  			PWRAP_WACS2_CMD);

@@ -457,10 +463,16 @@ static int pwrap_write(struct pmic_wrapper *wrp, u32 adr, u32 wdata)
  static int pwrap_read(struct pmic_wrapper *wrp, u32 adr, u32 *rdata)
  {
  	int ret;
+	u32 val;

  	ret = pwrap_wait_for_state(wrp, pwrap_is_fsm_idle);
-	if (ret)
+	if (ret) {
+		/* Clear vldclr bit if state is on the WACS_FSM_WFVLDCLR */
+		val = pwrap_readl(wrp, PWRAP_WACS2_RDATA);
+		if (PWRAP_GET_WACS_FSM(val) == PWRAP_WACS_FSM_WFVLDCLR)
+			pwrap_writel(wrp, 1, PWRAP_WACS2_VLDCLR);
  		return ret;
+	}

  	pwrap_writel(wrp, (adr >> 1) << 16, PWRAP_WACS2_CMD);