Re: [PATCH] soc: mediatek: PMIC wrap: Clear the vldclr if state machine is stay on FSM_VLDCLR state.

From: Matthias Brugger
Date: Wed Dec 30 2015 - 13:02:50 EST




On 22/12/15 08:51, Henry Chen wrote:
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 <henryc.chen@xxxxxxxxxxxx>
---
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


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);


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/